WorldWideScience

Sample records for accelerating agents

  1. Timing and Characteristics of Cumulative Evidence Available on Novel Therapeutic Agents Receiving Food and Drug Administration Accelerated Approval.

    Science.gov (United States)

    Naci, Huseyin; Wouters, Olivier J; Gupta, Radhika; Ioannidis, John P A

    2017-06-01

    Policy Points: Randomized trials-the gold standard of evaluating effectiveness-constitute a small minority of existing evidence on agents given accelerated approval. One-third of randomized trials are in therapeutic areas outside of FDA approval and less than half evaluate the therapeutic benefits of these agents but use them instead as common backbone treatments. Agents receiving accelerated approval are often tested concurrently in several therapeutic areas. For most agents, no substantial time lag is apparent between the average start dates of randomized trials evaluating their effectiveness and those using them as part of background therapies. There appears to be a tendency for therapeutic agents receiving accelerated approval to quickly become an integral component of standard treatment, despite potential shortcomings in their evidence base. Therapeutic agents treating serious conditions are eligible for Food and Drug Administration (FDA) accelerated approval. The clinical evidence accrued on agents receiving accelerated approval has not been systematically evaluated. Our objective was to assess the timing and characteristics of available studies. We first identified clinical studies of novel therapeutic agents receiving accelerated approval. We then (1) categorized those studies as randomized or nonrandomized, (2) explored whether they evaluated the FDA-approved indications, and (3) documented the available treatment comparisons. We also meta-analyzed the difference in start times between randomized studies that (1) did or did not evaluate approved indications and (2) were or were not designed to evaluate the agent's effectiveness. In total, 37 novel therapeutic agents received accelerated approval between 2000 and 2013. Our search of ClinicalTrials.gov identified 7,757 studies, which included 1,258,315 participants. Only one-third of identified studies were randomized controlled trials. Of 1,631 randomized trials with advanced recruitment status, 906 were

  2. Effect of luting agent on the load to failure and accelerated-fatigue resistance of lithium disilicate laminate veneers

    NARCIS (Netherlands)

    Gresnigt, Marco M. M.; Ozcan, Mutlu; Carualho, Marco; Lazari, Priscilla; Cune, Marco S.; Razavi, Peywand; Magne, Pascal

    2017-01-01

    Objective. The aim of this study was to investigate the influence of the luting agent on the application of laminate veneers (LVs) in an accelerated fatigue and load-to-failure test after thermo-cyclic aging. Methods. Sound maxillary central incisors (N = 40) were randomly divided into four groups

  3. Influence of Different Types of Resin Luting Agents on Color Stability of Ceramic Laminate Veneers Subjected to Accelerated Artificial Aging

    OpenAIRE

    Silami,Francisca Daniele Jardilino; Tonani,Rafaella; Alandia-Román,Carla Cecilia; Pires-de-Souza,Fernanda de Carvalho Panzeri

    2016-01-01

    Abstract The aim of this study was to evaluate the influence of accelerated aging (AAA) on the color stability of resin cements for bonding ceramic laminate veneers of different thicknesses. The occlusal surfaces of 80 healthy human molars were flattened. Ceramic laminate veneers (IPS e-max Ceram) of two thicknesses (0.5 and 1.0 mm) were bonded with three types of luting agents: light-cured, conventional dual and self-adhesive dual cement. Teeth without restorations and cement samples (0.5 mm...

  4. Nanosizing a Metal-Organic Framework Enzyme Carrier for Accelerating Nerve Agent Hydrolysis.

    Science.gov (United States)

    Li, Peng; Moon, Su-Young; Guelta, Mark A; Lin, Lu; Gómez-Gualdrón, Diego A; Snurr, Randall Q; Harvey, Steven P; Hupp, Joseph T; Farha, Omar K

    2016-10-05

    We report the synthesis and characterization of a water-stable zirconium metal-organic framework (MOF), NU-1003, featuring the largest mesoporous aperture known for a zirconium MOF. This material has been used to immobilize the nerve agent hydrolyzing enzyme, organophosphorus acid anhydrolase (OPAA). The catalytic efficiency of immobilized OPAA in nanosized NU-1003 is significantly increased compared to that of OPAA immobilized in microsized NU-1003 and even exceeds that of the free OPAA enzyme. This paper highlights a method for rapid and highly efficient hydrolysis of nerve agents using nanosized enzyme carriers.

  5. Effect of luting agent on the load to failure and accelerated-fatigue resistance of lithium disilicate laminate veneers.

    Science.gov (United States)

    Gresnigt, Marco M M; Özcan, Mutlu; Carvalho, Marco; Lazari, Priscilla; Cune, Marco S; Razavi, Peywand; Magne, Pascal

    2017-12-01

    The aim of this study was to investigate the influence of the luting agent on the application of laminate veneers (LVs) in an accelerated fatigue and load-to-failure test after thermo-cyclic aging. Sound maxillary central incisors (N=40) were randomly divided into four groups to receive LVs (Li 2 Si 2 O 5 ) that were adhesively bonded: Group CEMF: Adhesive cement (Variolink Esthetic LC), fatigue test; Group CEMLF: Adhesive cement, load-to-failure test; Group COMF: Resin composite (Enamel HFO), fatigue test; Group COMLF: Resin composite, load-to-failure test. The specimens were thermo-mechanically aged (1.2×10 6 cycles at 1.7Hz/50N, 8000 cycles 5-55°C) and then subjected to either accelerated fatigue (5Hz, 25N increasing after each 500 cycles) or load to failure (1mm/min). Failure types were classified and data analyzed using chi-square, Kaplan Meier survival, Log Rank (Mantel-Cox) and independent-samples t-test. After thermo-mechanical aging, fracture resistance (pveneer. The delivery of laminate veneers using a direct restorative composite rather than a resin cement resulted in significantly less chipping and fractures, higher fracture strength in both accelerated fatigue and load-to-failure. Copyright © 2017 The Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  6. Use of the accelerating rotarod for assessment of motor performance decrement induced by potential anticonvulsant compounds in nerve agent poisoning.

    Science.gov (United States)

    Capacio, B R; Harris, L W; Anderson, D R; Lennox, W J; Gales, V; Dawson, J S

    1992-01-01

    The accelerating rotarod was used to assess motor performance decrement in rats after administration of candidate anticonvulsant compounds (acetazolamide, amitriptyline, chlordiazepoxide, diazepam, diazepam-lysine, lorazepam, loprazolam, midazolam, phenobarbital and scopolamine) against nerve agent poisoning. All compounds were tested as the commercially available injectable preparation except for diazepam-lysine and loprazolam, which are not FDA approved. A peak effect time, as well as a dose to decrease performance time by 50% from control (PDD50), was determined. The calculated PDD50 (mumol/kg) values and peak effect times were midazolam, 1.16 at 15 min; loprazolam, 1.17 at 15 min; diazepam-lysine, 4.17 at 30 min; lorazepam, 4.98 at 15 min; diazepam, 5.27 at 15 min; phenobarbital, 101.49 at 45 min; chlordiazepoxide, 159.21 at 30 min; scopolamine, amitriptyline and acetazolamide did not demonstrate a performance decrement at any of the doses tested. The PDD50 values were compared with doses which have been utilized against nerve agent-induced convulsions or published ED50 values from standard anticonvulsant screening tests (maximal electroshock [MES] and subcutaneous pentylenetetrazol [scMET]). The results suggest that at anticonvulsant doses against nerve agents, all the benzodiazepines and phenobarbital have the potential to cause a performance decrement, whereas candidate anticonvulsants of the non-benzodiazepine or non-barbiturate type would not be expected to demonstrate this effect on motor performance. It is concluded that compounds such as acetazolamide, amitriptyline and scopolamine offer alternatives to the highly decrementing benzodiazepines and phenobarbital and should be further tested as anticonvulsant candidates against nerve agent intoxication.

  7. Coffee Silverskin Extract Protects against Accelerated Aging Caused by Oxidative Agents

    Directory of Open Access Journals (Sweden)

    Amaia Iriondo-DeHond

    2016-06-01

    Full Text Available Nowadays, coffee beans are almost exclusively used for the preparation of the beverage. The sustainability of coffee production can be achieved introducing new applications for the valorization of coffee by-products. Coffee silverskin is the by-product generated during roasting, and because of its powerful antioxidant capacity, coffee silverskin aqueous extract (CSE may be used for other applications, such as antiaging cosmetics and dermaceutics. This study aims to contribute to the coffee sector’s sustainability through the application of CSE to preserve skin health. Preclinical data regarding the antiaging properties of CSE employing human keratinocytes and Caenorhabditis elegans are collected during the present study. Accelerated aging was induced by tert-butyl hydroperoxide (t-BOOH in HaCaT cells and by ultraviolet radiation C (UVC in C. elegans. Results suggest that the tested concentrations of coffee extracts were not cytotoxic, and CSE 1 mg/mL gave resistance to skin cells when oxidative damage was induced by t-BOOH. On the other hand, nematodes treated with CSE (1 mg/mL showed a significant increased longevity compared to those cultured on a standard diet. In conclusion, our results support the antiaging properties of the CSE and its great potential for improving skin health due to its antioxidant character associated with phenols among other bioactive compounds present in the botanical material.

  8. Coffee Silverskin Extract Protects against Accelerated Aging Caused by Oxidative Agents.

    Science.gov (United States)

    Iriondo-DeHond, Amaia; Martorell, Patricia; Genovés, Salvador; Ramón, Daniel; Stamatakis, Konstantinos; Fresno, Manuel; Molina, Antonio; Del Castillo, Maria Dolores

    2016-06-01

    Nowadays, coffee beans are almost exclusively used for the preparation of the beverage. The sustainability of coffee production can be achieved introducing new applications for the valorization of coffee by-products. Coffee silverskin is the by-product generated during roasting, and because of its powerful antioxidant capacity, coffee silverskin aqueous extract (CSE) may be used for other applications, such as antiaging cosmetics and dermaceutics. This study aims to contribute to the coffee sector's sustainability through the application of CSE to preserve skin health. Preclinical data regarding the antiaging properties of CSE employing human keratinocytes and Caenorhabditis elegans are collected during the present study. Accelerated aging was induced by tert-butyl hydroperoxide (t-BOOH) in HaCaT cells and by ultraviolet radiation C (UVC) in C. elegans. Results suggest that the tested concentrations of coffee extracts were not cytotoxic, and CSE 1 mg/mL gave resistance to skin cells when oxidative damage was induced by t-BOOH. On the other hand, nematodes treated with CSE (1 mg/mL) showed a significant increased longevity compared to those cultured on a standard diet. In conclusion, our results support the antiaging properties of the CSE and its great potential for improving skin health due to its antioxidant character associated with phenols among other bioactive compounds present in the botanical material.

  9. Influence of Different Types of Resin Luting Agents on Color Stability of Ceramic Laminate Veneers Subjected to Accelerated Artificial Aging.

    Science.gov (United States)

    Silami, Francisca Daniele Jardilino; Tonani, Rafaella; Alandia-Román, Carla Cecilia; Pires-de-Souza, Fernanda de Carvalho Panzeri

    2016-01-01

    The aim of this study was to evaluate the influence of accelerated aging (AAA) on the color stability of resin cements for bonding ceramic laminate veneers of different thicknesses. The occlusal surfaces of 80 healthy human molars were flattened. Ceramic laminate veneers (IPS e-max Ceram) of two thicknesses (0.5 and 1.0 mm) were bonded with three types of luting agents: light-cured, conventional dual and self-adhesive dual cement. Teeth without restorations and cement samples (0.5 mm) were used as control. After initial color evaluations, the samples were subjected to AAA for 580 h. After this, new color readouts were made, and the color stability (ΔE) and luminosity (ΔL) data were analyzed. The greatest color changes (pveneers were fixed with light-cured cement and the lowest when 1.0 mm veneers were fixed with conventional dual cement. There was no influence of the restoration thickness when the self-adhesive dual cement was used. When veneers were compared with the control groups, it was verified that the cement samples presented the greatest alterations (p<0.05) in comparison with both substrates and restored teeth. Therefore, it was concluded that the thickness of the restoration influences color and luminosity changes for conventional dual and light-cured cements. The changes in self-adhesive cement do not depend on restoration thickness.

  10. Fate of the chemical warfare agent O-ethyl S-2-diisopropylaminoethyl methylphosphonothiolate (VX) on soil following accelerant-based fire and liquid decontamination.

    Science.gov (United States)

    Gravett, M R; Hopkins, F B; Self, A J; Webb, A J; Timperley, C M; Riches, J R

    2014-08-01

    In the event of alleged use of organophosphorus nerve agents, all kinds of environmental samples can be received for analysis. These might include decontaminated and charred matter collected from the site of a suspected chemical attack. In other scenarios, such matter might be sampled to confirm the site of a chemical weapon test or clandestine laboratory decontaminated and burned to prevent discovery. To provide an analytical capability for these contingencies, we present a preliminary investigation of the effect of accelerant-based fire and liquid decontamination on soil contaminated with the nerve agent O-ethyl S-2-diisopropylaminoethyl methylphosphonothiolate (VX). The objectives were (a) to determine if VX or its degradation products were detectable in soil after an accelerant-based fire promoted by aviation fuel, including following decontamination with Decontamination Solution 2 (DS2) or aqueous sodium hypochlorite, (b) to develop analytical methods to support forensic analysis of accelerant-soaked, decontaminated and charred soil and (c) to inform the design of future experiments of this type to improve analytical fidelity. Our results show for the first time that modern analytical techniques can be used to identify residual VX and its degradation products in contaminated soil after an accelerant-based fire and after chemical decontamination and then fire. Comparison of the gas chromatography-mass spectrometry (GC-MS) profiles of VX and its impurities/degradation products from contaminated burnt soil, and burnt soil spiked with VX, indicated that the fire resulted in the production of diethyl methylphosphonate and O,S-diethyl methylphosphonothiolate (by an unknown mechanism). Other products identified were indicative of chemical decontamination, and some of these provided evidence of the decontaminant used, for example, ethyl 2-methoxyethyl methylphosphonate and bis(2-methoxyethyl) methylphosphonate following decontamination with DS2. Sample preparation

  11. Use of the accelerating rotarod for assessment of motor performance decrement induced by potential anticonvulsant compounds in nerve agent poisoning. (Reannouncement with new availability information)

    Energy Technology Data Exchange (ETDEWEB)

    Capacio, B.R.; Harris, L.W.; Anderson, D.R.; Lennox, W.J.; Gales, V.

    1992-12-31

    The accelerating rotarod was used to assess motor performance decrement in rats after administration of candidate anticonvulsant compounds (acetazolamide, amitriptyline, chlordiazepoxide, diazepan, diazepam-lysine, lorazepam, loprazolam, midazolam, phenobarbital and scopolamine) against nerve agent poisoning. AH compounds were tested as the commercially available injectable preparation except for diazepam-lysine and loprazolam, which are not FDA approved. A peak effect time, as well as a dose to decrease performance time by 50% from control (PDD50), was determined. The calculated PDD50 (micrometer ol/kg) values and peak effect tunes were midazolam, 1.16 at 15 min; loprazolam, 1.17 at 15 min; diazepam-lysine, 4.17 at 30 min; lorazepwn, 4.98 at 15 min; diazepam, 5.27 at 15 min; phenobarbital, 101.49 at 45 min; chlordiazepoxide, 159.21 at 30 min; scopolamine, amitriptyline and acetazolamide did not demonstrate a performance decrement at any of the doses tested. The PDD50 values were compared with doses which have been utilized against nerve agent-induced convulsions or published ED50 values from standard anticonvulsant screening tests (maximal electroshock MES and subcutaneous pentylenetetrazol (scMET)). I serve agents, anticonvulsants, diazepam, accelerating rotarod, motor performance.

  12. Highly accelerated first-pass contrast-enhanced magnetic resonance angiography of the peripheral vasculature: comparison of gadofosveset trisodium with gadopentetate dimeglumine contrast agents.

    Science.gov (United States)

    Maki, Jeffrey H; Wang, Maisie; Wilson, Gregory J; Shutske, Matthew G; Leiner, Tim

    2009-11-01

    To investigate the blood pool agent gadofosveset trisodium for first-pass, dynamic peripheral contrast-enhanced magnetic resonance angiography (pMRA), and compare the results with a conventional gadolinium contrast agent. A total of 16 patients were imaged at 1.5T using a prototype peripheral vascular coil with high SENSE acceleration. Five received gadopentetate dimeglumine ( approximately 0.25 mmol/kg), and 11 received gadofosveset trisodium (five standard-dose 0.03 mmol/kg, six high-dose 0.05 mmol/kg). Quantitative contrast-enhancement and qualitative image quality evaluation was compared between agents and doses. High-quality diagnostic images were uniformly obtained. The contrast ratio did not significantly differ between gadopentetate dimeglumine and high-dose gadofosveset trisodium, both of which were greater than standard-dose gadofosveset trisodium. High-dose gadofosveset trisodium was equivalent to gadopentetate dimeglumine in image quality and subjective vessel-to-background ratio, but significantly better for depicting small muscular arteries. Standard-dose gadofosveset trisodium showed equivalent image quality and small artery depiction with a slight but significant decrease in vessel-to-background ratio as compared to gadopentatate dimeglumine. Both gadofosveset trisodium doses trended toward more venous enhancement, but this was not a diagnostic problem. First-pass peripheral CE-MRA using gadofosveset trisodium is feasible, yielding image quality comparable to double to triple-dose gadopentetate dimeglumine. Increasing the gadofosveset trisodium dose to 0.05 mmol/kg yields further improvements.

  13. Accelerator mass spectrometry analysis of {sup 14}C-oxaliplatin concentrations in biological samples and {sup 14}C contents in biological samples and antineoplastic agents

    Energy Technology Data Exchange (ETDEWEB)

    Toyoguchi, Teiko, E-mail: tteiko@med.id.yamagata-u.ac.jp [Department of Pharmacy, Yamagata University Hospital, 2-2-2 Iida-Nishi, Yamagata-shi, Yamagata 990-9585 (Japan); Kobayashi, Takeshi; Konno, Noboru; Shiraishi, Tadashi [Department of Pharmacy, Yamagata University Hospital, 2-2-2 Iida-Nishi, Yamagata-shi, Yamagata 990-9585 (Japan); Kato, Kazuhiro; Tokanai, Fuyuki [Department of Physics, Faculty of Science, Yamagata University, 1-4-12 Kojirakawa-machi, Yamagata-shi, Yamagata 990-8560 (Japan)

    2015-10-15

    Accelerator mass spectrometry (AMS) is expected to play an important role in microdose trials. In this study, we measured the {sup 14}C concentration in {sup 14}C-oxaliplatin-spiked serum, urine and supernatant of fecal homogenate samples in our Yamagata University (YU) – AMS system. The calibration curves of {sup 14}C concentration in serum, urine and supernatant of fecal homogenate were linear (the correlation coefficients were ⩾0.9893), and the precision and accuracy was within the acceptance criteria. To examine a {sup 14}C content of water in three vacuum blood collection tubes and a syringe were measured. {sup 14}C was not detected from water in these devices. The mean {sup 14}C content in urine samples of 6 healthy Japanese volunteers was 0.144 dpm/mL, and the intra-day fluctuation of {sup 14}C content in urine from a volunteer was little. The antineoplastic agents are administered to the patients in combination. Then, {sup 14}C contents of the antineoplastic agents were quantitated. {sup 14}C contents were different among 10 antineoplastic agents; {sup 14}C contents of paclitaxel injection and docetaxel hydrate injection were higher than those of the other injections. These results indicate that our quantitation method using YU-AMS system is suited for microdosing studies and that measurement of baseline and co-administered drugs might be necessary for the studies in low concentrations.

  14. Preclinical imaging and translational animal models of cancer for accelerated clinical implementation of nanotechnologies and macromolecular agents.

    Science.gov (United States)

    De Souza, Raquel; Spence, Tara; Huang, Huang; Allen, Christine

    2015-12-10

    The majority of animal models of cancer have performed poorly in terms of predicting clinical performance of new therapeutics, which are most often first evaluated in patients with advanced, metastatic disease. The development and use of metastatic models of cancer may enhance clinical translatability of preclinical studies focused on the development of nanotechnology-based drug delivery systems and macromolecular therapeutics, potentially accelerating their clinical implementation. It is recognized that the development and use of such models are not without challenge. Preclinical imaging tools offer a solution by allowing temporal and spatial characterization of metastatic lesions. This paper provides a review of imaging methods applicable for evaluation of novel therapeutics in clinically relevant models of advanced cancer. An overview of currently utilized models of oncology in small animals is followed by image-based development and characterization of visceral metastatic cancer models. Examples of imaging tools employed for metastatic lesion detection, evaluation of anti-tumor and anti-metastatic potential and biodistribution of novel therapies, as well as the co-development and/or use of imageable surrogates of response, are also discussed. While the focus is on development of macromolecular and nanotechnology-based therapeutics, examples with small molecules are included in some cases to illustrate concepts and approaches that can be applied in the assessment of nanotechnologies or macromolecules. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. Single breath-hold assessment of cardiac function using an accelerated 3D single breath-hold acquisition technique - comparison of an intravascular and extravascular contrast agent

    Science.gov (United States)

    2012-01-01

    Background Cardiovascular magnetic resonance (CMR) is the current gold standard for the assessment of left ventricular (LV) function. Repeated breath-holds are needed for standard multi-slice 2D cine steady-state free precession sequences (M2D-SSFP). Accelerated single breath-hold techniques suffer from low contrast between blood pool and myocardium. In this study an intravascular contrast agent was prospectively compared to an extravascular contrast agent for the assessment of LV function using a single-breath-hold 3D-whole-heart cine SSFP sequence (3D-SSFP). Methods LV function was assessed in fourteen patients on a 1.5 T MR-scanner (Philips Healthcare) using 32-channel coil technology. Patients were investigated twice using a 3D-SSFP sequence (acquisition time 18–25 s) after Gadopentetate dimeglumine (GdD, day 1) and Gadofosveset trisodium (GdT, day 2) administration. Image acquisition was accelerated using sensitivity encoding in both phase encoding directions (4xSENSE). CNR and BMC were both measured between blood and myocardium. The CNR incorporated noise measurements, while the BMC represented the coeffiancy between the signal from blood and myocardium [1]. Contrast to noise ratio (CNR), blood to myocardium contrast (BMC), image quality, LV functional parameters and intra-/interobserver variability were compared. A M2D-SSFP sequence was used as a reference standard on both days. Results All 3D-SSFP sequences were successfully acquired within one breath-hold after GdD and GdT administration. CNR and BMC were significantly (p < 0.05) higher using GdT compared to GdD, resulting in an improved endocardial definition. Using 3D-SSFP with GdT, Bland–Altman plots showed a smaller bias (95% confidence interval LVEF: 9.0 vs. 23.7) and regression analysis showed a stronger correlation to the reference standard (R2 = 0.92 vs. R2 = 0.71), compared to 3D-SSFP with GdD. Conclusions A single-breath-hold 3D-whole-heart cine SSFP sequence in combination

  16. Single breath-hold assessment of cardiac function using an accelerated 3D single breath-hold acquisition technique - comparison of an intravascular and extravascular contrast agent

    Directory of Open Access Journals (Sweden)

    Makowski Marcus R

    2012-07-01

    Full Text Available Abstract Background Cardiovascular magnetic resonance (CMR is the current gold standard for the assessment of left ventricular (LV function. Repeated breath-holds are needed for standard multi-slice 2D cine steady-state free precession sequences (M2D-SSFP. Accelerated single breath-hold techniques suffer from low contrast between blood pool and myocardium. In this study an intravascular contrast agent was prospectively compared to an extravascular contrast agent for the assessment of LV function using a single-breath-hold 3D-whole-heart cine SSFP sequence (3D-SSFP. Methods LV function was assessed in fourteen patients on a 1.5 T MR-scanner (Philips Healthcare using 32-channel coil technology. Patients were investigated twice using a 3D-SSFP sequence (acquisition time 18–25 s after Gadopentetate dimeglumine (GdD, day 1 and Gadofosveset trisodium (GdT, day 2 administration. Image acquisition was accelerated using sensitivity encoding in both phase encoding directions (4xSENSE. CNR and BMC were both measured between blood and myocardium. The CNR incorporated noise measurements, while the BMC represented the coeffiancy between the signal from blood and myocardium [1]. Contrast to noise ratio (CNR, blood to myocardium contrast (BMC, image quality, LV functional parameters and intra-/interobserver variability were compared. A M2D-SSFP sequence was used as a reference standard on both days. Results All 3D-SSFP sequences were successfully acquired within one breath-hold after GdD and GdT administration. CNR and BMC were significantly (p vs. 23.7 and regression analysis showed a stronger correlation to the reference standard (R2 = 0.92 vs. R2 = 0.71, compared to 3D-SSFP with GdD. Conclusions A single-breath-hold 3D-whole-heart cine SSFP sequence in combination with 32-channel technology and an intravascular contrast agent allows for the accurate and fast assessment of LV function. Trial registration The study was approved by the local

  17. Improved eradication of Clostridium difficile spores from toilets of hospitalized patients using an accelerated hydrogen peroxide as the cleaning agent

    Directory of Open Access Journals (Sweden)

    Dueck Christine

    2010-09-01

    Full Text Available Abstract Background C. difficle spores in the environment of patients with C. difficile associated disease (CDAD are difficult to eliminate. Bleach (5000 ppm has been advocated as an effective disinfectant for the environmental surfaces of patients with CDAD. Few alternatives to bleach for non-outbreak conditions have been evaluated in controlled healthcare studies. Methods This study was a prospective clinical comparison during non-outbreak conditions of the efficacy of an accelerated hydrogen peroxide cleaner (0.5% AHP to the currently used stabilized hydrogen peroxide cleaner (0.05% SHP at manufacturer recommended use-dilution with respect to spore removal from toilets in a tertiary care facility. The toilets used by patients who had diarrhea with and without C. difficile associated disease (CDAD were cultured for C. difficile and were monitored using an ultraviolet mark (UVM to assess cleaning compliance on a daily basis 5 days per week. A total of 243 patients and 714 samples were analysed. The culture results were included in the analysis only if the UVM audit from the same day confirmed that the toilet had been cleaned. Results Our data demonstrated that the efficacy of spore killing is formulation specific and cannot be generalized. The OxivirTB® AHP formulation resulted in statistically significantly (p = 0.0023 lower levels of toxigenic C. difficile spores in toilets of patients with CDAD compared to the SHP formulation that was routinely being used (28% vs 45% culture positive. The background level of toxigenic C. difficile spores was 10% in toilets of patients with diarrhea not due to CDAD. The UVM audit indicated that despite the enhanced twice-daily cleaning protocol for CDAD patients cleaning was not achieved on approximately 30 - 40% of the days tested. Conclusion Our data indicate that the AHP formulation evaluated that has some sporicidal activity was significantly better than the currently used SHP formulation. This AHP

  18. Inoculation with a psychrotrophic-thermophilic complex microbial agent accelerates onset and promotes maturity of dairy manure-rice straw composting under cold climate conditions.

    Science.gov (United States)

    Gou, Changlong; Wang, Yuqiong; Zhang, Xiqing; Lou, Yujie; Gao, Yunhang

    2017-11-01

    The objective was to determine the effects of psychrotrophic-thermophilic complex microbial agent (PTCMA) comprised of a psychrotrophic bacterium consortium (PBC) and a thermophilic cellulolytic fungi consortium (TCFC), on composting in a cold climate. Mixtures of dairy manure and rice straw were inoculated with PTCMA, PBC, TCFC and sterile water (control) and composted at an initial ambient temperatures of -2 to 5°C. In compost piles inoculated with PBC or PTCMA, temperatures reached the thermophilic phase (>55°C) faster (8-11d) than piles inoculated with TCFC or control. Furthermore, compost inoculated with TCFC or PTCMA had greater decreases in total organic carbon and carbon-to-nitrogen ratios, as well as significant increases in total nitrogen, degradation of cellulose and lignin and germination index than PBC inoculation or Control compost. Consequently, inoculation with both (i.e. PTCMA) accelerated the onset and promoted maturity of composting under cold-climate conditions. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Determination of fluoroquinolone antibacterial agents in sewage sludge and sludge-treated soil using accelerated solvent extraction followed by solid-phase extraction.

    Science.gov (United States)

    Golet, Eva M; Strehler, Adrian; Alder, Alfredo C; Giger, Walter

    2002-11-01

    A method for the quantitative determination of humanuse fluoroquinolone antibacterial agents (FQs) ciprofloxacin and norfloxacin in sewage sludge and sludge-treated soil samples was developed. The accelerated solvent extraction was optimized with regard to solvents and operational parameters, such as temperature, pressure, and extraction time. A 50 mM aqueous phosphoric acid/ acetonitrile mixture (1:1) was found to be optimum in combination with an extraction temperature of 100 degrees C at 100 bar, during 60 and 90 min for sewage sludge and sludge-treated soil samples, respectively. A cleanup step using solid-phase extraction substantially improved the selectivity of the method. Overall recovery rates for FQs ranged from 82 to 94% for sewage sludge and from 75 to 92% for sludge-treated soil, with relative standard deviations between 8 and 11%. Limits of quantification were 0.45 and 0.18 mg/kg of dry matter for sewage sludge and sludge-treated soils, respectively. The presented method was successfully applied to untreated and anaerobically digested sewage sludges and sludge-treated soils. Ciprofloxacin and norfloxacin were determined in sewage sludges from several wastewater treatment plants with concentrations ranging from 1.40 to 2.42 mg/kg of dry matter. Therefore, contrary to what may be expected for human-use pharmaceuticals, FQs may reach the terrestrial environment as indicated by the occurrence of FQs in topsoil samples from experimental fields, to which sewage sludge had been applied.

  20. Future accelerators (?)

    Energy Technology Data Exchange (ETDEWEB)

    John Womersley

    2003-08-21

    I describe the future accelerator facilities that are currently foreseen for electroweak scale physics, neutrino physics, and nuclear structure. I will explore the physics justification for these machines, and suggest how the case for future accelerators can be made.

  1. Electrostatic accelerators

    OpenAIRE

    Hinterberger, F.

    2006-01-01

    The principle of electrostatic accelerators is presented. We consider Cockcroft– Walton, Van de Graaff and Tandem Van de Graaff accelerators. We resume high voltage generators such as cascade generators, Van de Graaff band generators, Pelletron generators, Laddertron generators and Dynamitron generators. The speci c features of accelerating tubes, ion optics and methods of voltage stabilization are described. We discuss the characteristic beam properties and the variety of possible beams. We ...

  2. Electrostatic accelerators

    CERN Document Server

    Hinterberger, F

    2006-01-01

    The principle of electrostatic accelerators is presented. We consider Cockcroft– Walton, Van de Graaff and Tandem Van de Graaff accelerators. We resume high voltage generators such as cascade generators, Van de Graaff band generators, Pelletron generators, Laddertron generators and Dynamitron generators. The speci c features of accelerating tubes, ion optics and methods of voltage stabilization are described. We discuss the characteristic beam properties and the variety of possible beams. We sketch possible applications and the progress in the development of electrostatic accelerators.

  3. Accelerating Value Creation with Accelerators

    DEFF Research Database (Denmark)

    Jonsson, Eythor Ivar

    2015-01-01

    accelerator programs. Microsoft runs accelerators in seven different countries. Accelerators have grown out of the infancy stage and are now an accepted approach to develop new ventures based on cutting-edge technology like the internet of things, mobile technology, big data and virtual reality. It is also...... an approach to facilitate implementation and realization of business ideas and is a lucrative approach to transform research into ventures and to revitalize regions and industries in transition. Investors have noticed that the accelerator approach is a way to increase the possibility of success by funnelling...... with the traditional audit and legal universes and industries are examples of emerging potentials both from a research and business point of view to exploit and explore further. The accelerator approach may therefore be an Idea Watch to consider, no matter which industry you are in, because in essence accelerators...

  4. The in vivo performance of a novel thermal accelerant agent used for augmentation of microwave energy delivery within biologic tissues during image-guided thermal ablation: a porcine study.

    Science.gov (United States)

    Park, William Keun Chan; Maxwell, Aaron Wilhelm Palmer; Frank, Victoria Elizabeth; Primmer, Michael Patrick; Paul, Jarod Brian; Collins, Scott Andrew; Lombardo, Kara Anne; Lu, Shaolei; Borjeson, Tiffany Marie; Baird, Grayson Luderman; Dupuy, Damian Edward

    2018-02-01

    To investigate the effects of a novel caesium-based thermal accelerant (TA) agent on ablation zone volumes following in vivo microwave ablation of porcine liver and skeletal muscle, and to correlate the effects of TA with target organ perfusion. This prospective study was performed following institutional animal care and use committee approval. Microwave ablation was performed in liver and resting skeletal muscle in eight Sus scrofa domesticus swine following administration of TA at concentrations of 0 mg/mL (control), 100 mg/mL and 250 mg/mL. Treated tissues were explanted and stained with triphenyltetrazolium chloride (TTC) for quantification of ablation zone volumes, which were compared between TA and control conditions. Hematoxylin and eosin (H&E) staining was also performed for histologic analysis. General mixed modelling with a log-normal distribution was used for all quantitative comparisons (p = 0.05). A total of 28 ablations were performed in the liver and 18 in the skeletal muscle. The use of TA significantly increased ablation zone volumes in a dose-dependent manner in both the porcine muscle and liver (p model. The relationship between TA administration and ablation size was dose-dependent and inversely proportional to the degree of target organ perfusion, and a qualitative reduction in heat-sink effects was observed.

  5. LIBO accelerates

    CERN Multimedia

    2002-01-01

    The prototype module of LIBO, a linear accelerator project designed for cancer therapy, has passed its first proton-beam acceleration test. In parallel a new version - LIBO-30 - is being developed, which promises to open up even more interesting avenues.

  6. Accelerating Inspire

    CERN Document Server

    AUTHOR|(CDS)2266999

    2017-01-01

    CERN has been involved in the dissemination of scientific results since its early days and has continuously updated the distribution channels. Currently, Inspire hosts catalogues of articles, authors, institutions, conferences, jobs, experiments, journals and more. Successful orientation among this amount of data requires comprehensive linking between the content. Inspire has lacked a system for linking experiments and articles together based on which accelerator they were conducted at. The purpose of this project has been to create such a system. Records for 156 accelerators were created and all 2913 experiments on Inspire were given corresponding MARC tags. Records of 18404 accelerator physics related bibliographic entries were also tagged with corresponding accelerator tags. Finally, as a part of the endeavour to broaden CERN's presence on Wikipedia, existing Wikipedia articles of accelerators were updated with short descriptions and links to Inspire. In total, 86 Wikipedia articles were updated. This repo...

  7. Induction accelerators

    CERN Document Server

    Takayama, Ken

    2011-01-01

    A broad class of accelerators rests on the induction principle whereby the accelerating electrical fields are generated by time-varying magnetic fluxes. Particularly suitable for the transport of bright and high-intensity beams of electrons, protons or heavy ions in any geometry (linear or circular) the research and development of induction accelerators is a thriving subfield of accelerator physics. This text is the first comprehensive account of both the fundamentals and the state of the art about the modern conceptual design and implementation of such devices. Accordingly, the first part of the book is devoted to the essential features of and key technologies used for induction accelerators at a level suitable for postgraduate students and newcomers to the field. Subsequent chapters deal with more specialized and advanced topics.

  8. Cosmic Acceleration

    Science.gov (United States)

    Bean, Rachel

    2011-03-01

    In this series of lectures we review observational evidence for, and theoretical investigations into, cosmic acceleration and dark energy. The notes are in four sections. First I review the basic cosmological formalism to describe the expansion history of the universe and how distance measures are defined. The second section covers the evidence for cosmic acceleration from cosmic distance measurements. Section 3 discusses the theoretical avenues being considered to explain the cosmological observations. Section 4 discusses how the growth of inhomogeneities and large scale structure observations might help us pin down the theoretical origin of cosmic acceleration.

  9. Horizontal Accelerator

    Data.gov (United States)

    Federal Laboratory Consortium — The Horizontal Accelerator (HA) Facility is a versatile research tool available for use on projects requiring simulation of the crash environment. The HA Facility is...

  10. Accelerated construction

    Science.gov (United States)

    2004-01-01

    Accelerated Construction Technology Transfer (ACTT) is a strategic process that uses various innovative techniques, strategies, and technologies to minimize actual construction time, while enhancing quality and safety on today's large, complex multip...

  11. LINEAR ACCELERATOR

    Science.gov (United States)

    Christofilos, N.C.; Polk, I.J.

    1959-02-17

    Improvements in linear particle accelerators are described. A drift tube system for a linear ion accelerator reduces gap capacity between adjacent drift tube ends. This is accomplished by reducing the ratio of the diameter of the drift tube to the diameter of the resonant cavity. Concentration of magnetic field intensity at the longitudinal midpoint of the external sunface of each drift tube is reduced by increasing the external drift tube diameter at the longitudinal center region.

  12. Laser acceleration

    Science.gov (United States)

    Tajima, T.; Nakajima, K.; Mourou, G.

    2017-02-01

    The fundamental idea of Laser Wakefield Acceleration (LWFA) is reviewed. An ultrafast intense laser pulse drives coherent wakefield with a relativistic amplitude robustly supported by the plasma. While the large amplitude of wakefields involves collective resonant oscillations of the eigenmode of the entire plasma electrons, the wake phase velocity ˜ c and ultrafastness of the laser pulse introduce the wake stability and rigidity. A large number of worldwide experiments show a rapid progress of this concept realization toward both the high-energy accelerator prospect and broad applications. The strong interest in this has been spurring and stimulating novel laser technologies, including the Chirped Pulse Amplification, the Thin Film Compression, the Coherent Amplification Network, and the Relativistic Mirror Compression. These in turn have created a conglomerate of novel science and technology with LWFA to form a new genre of high field science with many parameters of merit in this field increasing exponentially lately. This science has triggered a number of worldwide research centers and initiatives. Associated physics of ion acceleration, X-ray generation, and astrophysical processes of ultrahigh energy cosmic rays are reviewed. Applications such as X-ray free electron laser, cancer therapy, and radioisotope production etc. are considered. A new avenue of LWFA using nanomaterials is also emerging.

  13. Accelerators and the Accelerator Community

    Energy Technology Data Exchange (ETDEWEB)

    Malamud, Ernest; Sessler, Andrew

    2008-06-01

    In this paper, standing back--looking from afar--and adopting a historical perspective, the field of accelerator science is examined. How it grew, what are the forces that made it what it is, where it is now, and what it is likely to be in the future are the subjects explored. Clearly, a great deal of personal opinion is invoked in this process.

  14. accelerating cavity

    CERN Multimedia

    On the inside of the cavity there is a layer of niobium. Operating at 4.2 degrees above absolute zero, the niobium is superconducting and carries an accelerating field of 6 million volts per metre with negligible losses. Each cavity has a surface of 6 m2. The niobium layer is only 1.2 microns thick, ten times thinner than a hair. Such a large area had never been coated to such a high accuracy. A speck of dust could ruin the performance of the whole cavity so the work had to be done in an extremely clean environment.

  15. Interactive teaching strategies for agent training

    OpenAIRE

    Amir, Ofra; Kamar, Ece; Kolobov, Andrey; Grosz, Barbara J.

    2016-01-01

    Agents learning how to act in new environments can benefit from input from more experienced agents or humans. This paper studies interactive teaching strategies for identifying when a student can benefit from teacher-advice in a reinforcement learning framework. In student-teacher learning, a teacher agent can advise the student on which action to take. Prior work has considered heuristics for the teacher to choose advising opportunities. While these approaches effectively accelerate agent tr...

  16. Piezoelectric particle accelerator

    Science.gov (United States)

    Kemp, Mark A.; Jongewaard, Erik N.; Haase, Andrew A.; Franzi, Matthew

    2017-08-29

    A particle accelerator is provided that includes a piezoelectric accelerator element, where the piezoelectric accelerator element includes a hollow cylindrical shape, and an input transducer, where the input transducer is disposed to provide an input signal to the piezoelectric accelerator element, where the input signal induces a mechanical excitation of the piezoelectric accelerator element, where the mechanical excitation is capable of generating a piezoelectric electric field proximal to an axis of the cylindrical shape, where the piezoelectric accelerator is configured to accelerate a charged particle longitudinally along the axis of the cylindrical shape according to the piezoelectric electric field.

  17. What good are actions? Accelerating learning using learned action priors

    CSIR Research Space (South Africa)

    Rosman, Benjamin S

    2012-11-01

    Full Text Available The computational complexity of learning in sequential decision problems grows exponentially with the number of actions available to the agent at each state. We present a method for accelerating this process by learning action priors that express...

  18. 2014 CERN Accelerator Schools: Plasma Wake Acceleration

    CERN Multimedia

    2014-01-01

    A specialised school on Plasma Wake Acceleration will be held at CERN, Switzerland from 23-29 November, 2014.   This course will be of interest to staff and students in accelerator laboratories, university departments and companies working in or having an interest in the field of new acceleration techniques. Following introductory lectures on plasma and laser physics, the course will cover the different components of a plasma wake accelerator and plasma beam systems. An overview of the experimental studies, diagnostic tools and state of the art wake acceleration facilities, both present and planned, will complement the theoretical part. Topical seminars and a visit of CERN will complete the programme. Further information can be found at: http://cas.web.cern.ch/cas/PlasmaWake2014/CERN-advert.html http://indico.cern.ch/event/285444/

  19. High Energy Particle Accelerators

    CERN Multimedia

    Audio Productions, Inc, New York

    1960-01-01

    Film about the different particle accelerators in the US. Nuclear research in the US has developed into a broad and well-balanced program.Tour of accelerator installations, accelerator development work now in progress and a number of typical experiments with high energy particles. Brookhaven, Cosmotron. Univ. Calif. Berkeley, Bevatron. Anti-proton experiment. Negative k meson experiment. Bubble chambers. A section on an electron accelerator. Projection of new accelerators. Princeton/Penn. build proton synchrotron. Argonne National Lab. Brookhaven, PS construction. Cambridge Electron Accelerator; Harvard/MIT. SLAC studying a linear accelerator. Other research at Madison, Wisconsin, Fixed Field Alternate Gradient Focusing. (FFAG) Oakridge, Tenn., cyclotron. Two-beam machine. Comments : Interesting overview of high energy particle accelerators installations in the US in these early years. .

  20. Improved plasma accelerator

    Science.gov (United States)

    Cheng, D. Y.

    1971-01-01

    Converging, coaxial accelerator electrode configuration operates in vacuum as plasma gun. Plasma forms by periodic injections of high pressure gas that is ionized by electrical discharges. Deflagration mode of discharge provides acceleration, and converging contours of plasma gun provide focusing.

  1. The CERN Accelerator School

    CERN Multimedia

    2016-01-01

    Introduction to accelerator physics The CERN Accelerator School: Introduction to Accelerator Physics, which should have taken place in Istanbul, Turkey, later this year has now been relocated to Budapest, Hungary.  Further details regarding the new hotel and dates will be made available as soon as possible on a new Indico site at the end of May.

  2. Accelerators and Dinosaurs

    CERN Multimedia

    Turner, Michael Stanley

    2003-01-01

    Using naturally occuring particles on which to research might have made accelerators become extinct. But in fact, results from astrophysics have made accelerator physics even more important. Not only are accelerators used in hospitals but they are also being used to understand nature's inner workings by searching for Higgs bosons, CP violation, neutrino mass and dark matter (2 pages)

  3. The Accelerator Reliability Forum

    CERN Document Server

    Lüdeke, Andreas; Giachino, R

    2014-01-01

    A high reliability is a very important goal for most particle accelerators. The biennial Accelerator Reliability Workshop covers topics related to the design and operation of particle accelerators with a high reliability. In order to optimize the over-all reliability of an accelerator one needs to gather information on the reliability of many different subsystems. While a biennial workshop can serve as a platform for the exchange of such information, the authors aimed to provide a further channel to allow for a more timely communication: the Particle Accelerator Reliability Forum [1]. This contribution will describe the forum and advertise it’s usage in the community.

  4. Industrial Application of Accelerators

    CERN Multimedia

    CERN. Geneva

    2017-01-01

    At CERN, we are very familiar with large, high energy particle accelerators. However, in the world outside CERN, there are more than 35000 accelerators which are used for applications ranging from treating cancer, through making better electronics to removing harmful micro-organisms from food and water. These are responsible for around $0.5T of commerce each year. Almost all are less than 20 MeV and most use accelerator types that are somewhat different from what is at CERN. These lectures will describe some of the most common applications, some of the newer applications in development and the accelerator technology used for them. It will also show examples of where technology developed for particle physics is now being studied for these applications. Rob Edgecock is a Professor of Accelerator Science, with a particular interest in the medical applications of accelerators. He works jointly for the STFC Rutherford Appleton Laboratory and the International Institute for Accelerator Applications at the Univer...

  5. Industrial Application of Accelerators

    CERN Multimedia

    CERN. Geneva

    2017-01-01

    At CERN, we are very familiar with large, high energy particle accelerators. However, in the world outside CERN, there are more than 35000 accelerators which are used for applications ranging from treating cancer, through making better electronics to removing harmful micro-organisms from food and water. These are responsible for around $0.5T of commerce each year. Almost all are less than 20 MeV and most use accelerator types that are somewhat different from what is at CERN. These lectures will describe some of the most common applications, some of the newer applications in development and the accelerator technology used for them. It will also show examples of where technology developed for particle physics is now being studied for these applications. Rob Edgecock is a Professor of Accelerator Science, with a particular interest in the medical applications of accelerators. He works jointly for the STFC Rutherford Appleton Laboratory and the International Institute for Accelerator Applications at the Uni...

  6. Trading Agents

    CERN Document Server

    Wellman, Michael

    2011-01-01

    Automated trading in electronic markets is one of the most common and consequential applications of autonomous software agents. Design of effective trading strategies requires thorough understanding of how market mechanisms operate, and appreciation of strategic issues that commonly manifest in trading scenarios. Drawing on research in auction theory and artificial intelligence, this book presents core principles of strategic reasoning that apply to market situations. The author illustrates trading strategy choices through examples of concrete market environments, such as eBay, as well as abst

  7. Accelerator and radiation physics

    CERN Document Server

    Basu, Samita; Nandy, Maitreyee

    2013-01-01

    "Accelerator and radiation physics" encompasses radiation shielding design and strategies for hadron therapy accelerators, neutron facilities and laser based accelerators. A fascinating article describes detailed transport theory and its application to radiation transport. Detailed information on planning and design of a very high energy proton accelerator can be obtained from the article on radiological safety of J-PARC. Besides safety for proton accelerators, the book provides information on radiological safety issues for electron synchrotron and prevention and preparedness for radiological emergencies. Different methods for neutron dosimetry including LET based monitoring, time of flight spectrometry, track detectors are documented alongwith newly measured experimental data on radiation interaction with dyes, polymers, bones and other materials. Design of deuteron accelerator, shielding in beam line hutches in synchrotron and 14 MeV neutron generator, various radiation detection methods, their characteriza...

  8. Nonparaxial accelerating Talbot effect

    CERN Document Server

    Zhang, Yiqi; Belić, Milivoj R; Li, Changbiao; Zhang, Zhaoyang; Wen, Feng; Zhang, Yanpeng; Xiao, Min

    2016-01-01

    We demonstrate the Talbot effect of nonpraxial accelerating beams, theoretically and numerically. It is based on the interference of nonparaxial accelerating solutions of the Helmholtz equation in two dimensions. The effect originates from the interference of such solutions that accelerate along concentric semicircular trajectories with different radii. The Talbot images form along certain central angles, which are referred to as the Talbot angles. These angles are inversely proportional to the radial differences between the nearest beams, which are equal and fixed. A single nonparaxial accelerating beam possesses duality - it can be viewed as a Talbot effect of itself with an infinite or zero Talbot angle. By choosing the coefficient for each beam component properly, we also obtain the fractional nonparaxial accelerating Talbot effect. These results improve the understanding of nonparaxial accelerating beams and the Talbot effect among them.

  9. Accelerator reliability workshop

    Energy Technology Data Exchange (ETDEWEB)

    Hardy, L.; Duru, Ph.; Koch, J.M.; Revol, J.L.; Van Vaerenbergh, P.; Volpe, A.M.; Clugnet, K.; Dely, A.; Goodhew, D

    2002-07-01

    About 80 experts attended this workshop, which brought together all accelerator communities: accelerator driven systems, X-ray sources, medical and industrial accelerators, spallation sources projects (American and European), nuclear physics, etc. With newly proposed accelerator applications such as nuclear waste transmutation, replacement of nuclear power plants and others. Reliability has now become a number one priority for accelerator designers. Every part of an accelerator facility from cryogenic systems to data storage via RF systems are concerned by reliability. This aspect is now taken into account in the design/budget phase, especially for projects whose goal is to reach no more than 10 interruptions per year. This document gathers the slides but not the proceedings of the workshop.

  10. Radioprotective Agents

    Directory of Open Access Journals (Sweden)

    Ilker Kelle

    2008-01-01

    Full Text Available Since1949, a great deal of research has been carried out on the radioprotective activity of various chemical substances. Thiol compounds, compounds which contain –SH radical, different classes of pharmacological agents and other compounds such as vitamine C and WR-2721 have been shown to reduce mortality when administered prior to exposure to a lethal dose of radiation. Recently, honey bee venom as well as that of its components melittin and histamine have shown to be valuable in reduction of radiation-induced damage and also provide prophylactic alternative treatment for serious side effects related with radiotherapy. It has been suggested that the radioprotective activity of bee venom components is related with the stimulation of the hematopoetic system.

  11. Miniaturization Techniques for Accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Spencer, James E.

    2003-05-27

    The possibility of laser driven accelerators [1] suggests the need for new structures based on micromachining and integrated circuit technology because of the comparable scales. Thus, we are exploring fully integrated structures including sources, optics (for both light and particle) and acceleration in a common format--an accelerator-on-chip (AOC). Tests suggest a number of preferred materials and techniques but no technical or fundamental roadblocks at scales of order 1 {micro}m or larger.

  12. Power Converters for Accelerators

    CERN Document Server

    Visintini, R.

    2015-06-15

    Particle accelerators use a great variety of power converters for energizing their sub-systems; while the total number of power converters usually depends on the size of the accelerator or combination of accelerators (including the experimental setup), the characteristics of power converters depend on their loads and on the particle physics requirements: this paper aims to provide an overview of the magnet power converters in use in several facilities worldwide.

  13. High Gradient Accelerator Research

    Energy Technology Data Exchange (ETDEWEB)

    Temkin, Richard [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States). Dept. of Physics. Plasma Science and Fusion Center

    2016-07-12

    The goal of the MIT program of research on high gradient acceleration is the development of advanced acceleration concepts that lead to a practical and affordable next generation linear collider at the TeV energy level. Other applications, which are more near-term, include accelerators for materials processing; medicine; defense; mining; security; and inspection. The specific goals of the MIT program are: • Pioneering theoretical research on advanced structures for high gradient acceleration, including photonic structures and metamaterial structures; evaluation of the wakefields in these advanced structures • Experimental research to demonstrate the properties of advanced structures both in low-power microwave cold test and high-power, high-gradient test at megawatt power levels • Experimental research on microwave breakdown at high gradient including studies of breakdown phenomena induced by RF electric fields and RF magnetic fields; development of new diagnostics of the breakdown process • Theoretical research on the physics and engineering features of RF vacuum breakdown • Maintaining and improving the Haimson / MIT 17 GHz accelerator, the highest frequency operational accelerator in the world, a unique facility for accelerator research • Providing the Haimson / MIT 17 GHz accelerator facility as a facility for outside users • Active participation in the US DOE program of High Gradient Collaboration, including joint work with SLAC and with Los Alamos National Laboratory; participation of MIT students in research at the national laboratories • Training the next generation of Ph. D. students in the field of accelerator physics.

  14. Accelerator Review Report 2014

    OpenAIRE

    Tovey, Dan; Appleby, Rob; Bartolini, Riccardo; Bruning, Oliver; Clarke, Jim; Flint, Jonathan; Kilcoyne, Susan H.; Thomason, John; Jamieson, Charlotte; The Accelerator Science and Technology Centre (ASTeC); The Cockcroft Institute (CI); The John Adams Institute for Accelerator Science (JAI)

    2014-01-01

    The panel was created to review the accelerator programme and provide information on the breadth and scope of the STFC’s current accelerator R&D portfolio. The review’s prime driver is to underpin the development of the STFC accelerator landscape and strategy. The panel’s report will go to SB for comment and development of a high-level accelerator strategy, taking into account information from parallel reviews on neutron and photon activities. The ASB will then establish a more detailed accel...

  15. Agent Building Software

    Science.gov (United States)

    2000-01-01

    AgentBuilder is a software component developed under an SBIR contract between Reticular Systems, Inc., and Goddard Space Flight Center. AgentBuilder allows software developers without experience in intelligent agent technologies to easily build software applications using intelligent agents. Agents are components of software that will perform tasks automatically, with no intervention or command from a user. AgentBuilder reduces the time and cost of developing agent systems and provides a simple mechanism for implementing high-performance agent systems.

  16. Beam Diagnostics for Accelerators

    CERN Document Server

    Koziol, Heribert

    2005-01-01

    This introductory course aims at a reasonably complete coverage of beam diagnostic devices used in linear and circular accelerators and in primary beam lines. The weight is on the concepts and the indication of variants, while for technical details the reader is referred to the literature. The present updated version replaces those from previous General Accelerator Physics Courses.

  17. Accelerators Beyond The Tevatron?

    Energy Technology Data Exchange (ETDEWEB)

    Lach, Joseph; /Fermilab

    2010-07-01

    Following the successful operation of the Fermilab superconducting accelerator three new higher energy accelerators were planned. They were the UNK in the Soviet Union, the LHC in Europe, and the SSC in the United States. All were expected to start producing physics about 1995. They did not. Why?

  18. Asia honours accelerator physicists

    CERN Multimedia

    2010-01-01

    "Steve Meyers of Cern and Jie Wei of Beijing's Tsinghua University are the first recipients of a new prize for particle physics. The pair were honoured for their contributions to numerous particle-accelerator projects - including Cern's Large Hadron Collider - by the Asian Committee for Future Accelerators (ACFA)..." (1 paragraph)

  19. 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.

  20. The Atomki accelerator center

    Science.gov (United States)

    Vajda, I.; Fülöp, Zs.; Biri, S.

    2017-06-01

    Particle accelerators are the driving forces of nuclear physics laboratories and MTA Atomki, the Institute for Nuclear Research of the Hungarian Academy of Sciences is no exception. The Atomki Accelerator Center (AAC) incorporates several low-energy charged-particle accelerators, offering the possibility of choosing ions with various charge states, energies and beam intensities. Currently, the AAC has six main facilities: a cyclotron (K=20), two Van de Graaff accelerators (1 MV, 5 MV), an ECR ion source, an electromagnetic isotope separator and a 2 MV Tandetron installed in 2015. The accelerators, spanning a range of beam energies from 50 eV to 27 MeV, have been designed for a broad range of research projects and applications in various fields - mainly in nuclear and atomic physics, materials science, environmental research and archaeology. The structure of the laboratory with a short description of the most important topics, education and outreach activities are presented.

  1. Neuroscience and Accelerator Mass Spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Palmblad, M N; Buchholz, B A; Hillegonds, D J; Vogel, J S

    2004-08-02

    Accelerator mass spectrometry (AMS) is a mass spectrometric method for quantifying rare isotopes. It has had great impact in geochronology and archaeology and is now being applied in biomedicine. AMS measures radioisotopes such as {sup 3}H, {sup 14}C, {sup 26}Al, {sup 36}Cl and {sup 41}Ca, with zepto- or attomole sensitivity and high precision and throughput, enabling safe human pharmacokinetic studies involving: microgram doses, agents having low bioavailability, or toxicology studies where administered doses must be kept low (<1 {micro}g/kg). It is used to study long-term pharmacokinetics, to identify biomolecular interactions, to determine chronic and low-dose effects or molecular targets of neurotoxic substances, to quantify transport across the blood-brain barrier and to resolve molecular turnover rates in the human brain on the timescale of decades. We will here review how AMS is applied in neurotoxicology and neuroscience.

  2. The miniature accelerator

    CERN Multimedia

    Antonella Del Rosso

    2015-01-01

    The image that most people have of CERN is of its enormous accelerators and their capacity to accelerate particles to extremely high energies. But thanks to some cutting-edge studies on beam dynamics and radiofrequency technology, along with innovative construction techniques, teams at CERN have now created the first module of a brand-new accelerator, which will be just 2 metres long. The potential uses of this miniature accelerator will include deployment in hospitals for the production of medical isotopes and the treatment of cancer. It’s a real David-and-Goliath story.   Serge Mathot, in charge of the construction of the "mini-RFQ", pictured with the first of the four modules that will make up the miniature accelerator. The miniature accelerator consists of a radiofrequency quadrupole (RFQ), a component found at the start of all proton accelerator chains around the world, from the smallest to the largest. The LHC is designed to produce very high-intensity beams ...

  3. Multicavity proton cyclotron accelerator

    Directory of Open Access Journals (Sweden)

    J. L. Hirshfield

    2002-08-01

    Full Text Available A mechanism for acceleration of protons is described, in which energy gain occurs near cyclotron resonance as protons drift through a sequence of rotating-mode TE_{111} cylindrical cavities in a strong nearly uniform axial magnetic field. Cavity resonance frequencies decrease in sequence from one another with a fixed frequency interval Δf between cavities, so that synchronism can be maintained between the rf fields and proton bunches injected at intervals of 1/Δf. An example is presented in which a 122 mA, 1 MeV proton beam is accelerated to 961 MeV using a cascade of eight cavities in an 8.1 T magnetic field, with the first cavity resonant at 120 MHz and with Δf=8 MHz. Average acceleration gradient exceeds 40 MV/m, average effective shunt impedance is 223 MΩ/m, but maximum surface field in the cavities does not exceed 7.2 MV/m. These features occur because protons make many orbital turns in each cavity and thus experience acceleration from each cavity field many times. Longitudinal and transverse stability appear to be intrinsic properties of the acceleration mechanism, and an example to illustrate this is presented. This acceleration concept could be developed into a proton accelerator for a high-power neutron spallation source, such as that required for transmutation of nuclear waste or driving a subcritical fission burner, provided a number of significant practical issues can be addressed.

  4. Direct Laser Acceleration in Laser Wakefield Accelerators

    Science.gov (United States)

    Shaw, J. L.; Froula, D. H.; Marsh, K. A.; Joshi, C.; Lemos, N.

    2017-10-01

    The direct laser acceleration (DLA) of electrons in a laser wakefield accelerator (LWFA) has been investigated. We show that when there is a significant overlap between the drive laser and the trapped electrons in a LWFA cavity, the accelerating electrons can gain energy from the DLA mechanism in addition to LWFA. The properties of the electron beams produced in a LWFA, where the electrons are injected by ionization injection, have been investigated using particle-in-cell (PIC) code simulations. Particle tracking was used to demonstrate the presence of DLA in LWFA. Further PIC simulations comparing LWFA with and without DLA show that the presence of DLA can lead to electron beams that have maximum energies that exceed the estimates given by the theory for the ideal blowout regime. The magnitude of the contribution of DLA to the energy gained by the electron was found to be on the order of the LWFA contribution. The presence of DLA in a LWFA can also lead to enhanced betatron oscillation amplitudes and increased divergence in the direction of the laser polarization. This material is based upon work supported by the Department of Energy National Nuclear Security Administration under Award Number DE-NA0001944.

  5. RF linear accelerators

    CERN Document Server

    Wangler, Thomas P

    2008-01-01

    Thomas P. Wangler received his B.S. degree in physics from Michigan State University, and his Ph.D. degree in physics and astronomy from the University of Wisconsin. After postdoctoral appointments at the University of Wisconsin and Brookhaven National Laboratory, he joined the staff of Argonne National Laboratory in 1966, working in the fields of experimental high-energy physics and accelerator physics. He joined the Accelerator Technology Division at Los Alamos National Laboratory in 1979, where he specialized in high-current beam physics and linear accelerator design and technology. In 2007

  6. Confronting Twin Paradox Acceleration

    Science.gov (United States)

    Murphy, Thomas W.

    2016-05-01

    The resolution to the classic twin paradox in special relativity rests on the asymmetry of acceleration. Yet most students are not exposed to a satisfactory analysis of what exactly happens during the acceleration phase that results in the nonaccelerated observer's more rapid aging. The simple treatment presented here offers both graphical and quantitative solutions to the problem, leading to the correct result that the acceleration-induced age gap is 2Lβ years when the one-way distance L is expressed in light-years and velocity β ≡v/c .

  7. Accelerator Production of Radionuclides

    Science.gov (United States)

    Schlyer, David J.; Ruth, Thomas J.

    2012-06-01

    While many radioactive isotopes in use today are found in nature, many more are artificially produced by irradiating target materials with nuclear particles. Two different technologies can provide the energetic particles needed: nuclear reactors, which produce a flux of neutrons, and particle accelerators, which produce a flux of charged particles. This chapter will deal with the important aspects of the production of radionuclides with accelerators, along with some details on their applications, commercially-available accelerator systems used for this purpose, and the size of the equipment business.

  8. Non-accelerator experiments

    Energy Technology Data Exchange (ETDEWEB)

    Goldhaber, M.

    1986-01-01

    This report discusses several topics which can be investigated without the use of accelerators. Topics covered are: (1) proton decay, (2) atmospheric neutrinos, (3) neutrino detection, (4) muons from Cygnus X-3, and (5) the double-beta decay.

  9. Macromolecular ion accelerator.

    Science.gov (United States)

    Hsu, Yun-Fei; Lin, Jung-Lee; Lai, Szu-Hsueh; Chu, Ming-Lee; Wang, Yi-Sheng; Chen, Chung-Hsuan

    2012-07-03

    Presented herein are the development of macromolecular ion accelerator (MIA) and the results obtained by MIA. This new instrument utilizes a consecutive series of planar electrodes for the purpose of facilitating stepwise acceleration. Matrix-assisted laser desorption/ionization (MALDI) is employed to generate singly charged macromolecular ions. A regular Z-gap microchannel plate (MCP) detector is mounted at the end of the accelerator to record the ion signals. In this work, we demonstrated the detection of ions with the mass-to-charge (m/z) ratio reaching 30,000,000. Moreover, we showed that singly charged biomolecular ions can be accelerated with the voltage approaching 1 MV, offering the evidence that macromolecular ions can possess much higher kinetic energy than ever before.

  10. The next big accelerator

    CERN Multimedia

    Cramer, J G

    2002-01-01

    Accelerator physics in the US has been devastated by the cancellation of two high-energy physics colliders facilities. However there are future plans. A suggestion is made to build the new collider in the Australian outback.

  11. Accelerated learning in Afghanistan

    Directory of Open Access Journals (Sweden)

    Christine Capacci Carneal

    2005-01-01

    Full Text Available Most accelerated learning (AL programmes are ‘catch up’ initiatives to assist out-of-school youth into formal education. But what happens when adults join and complete AL classes?

  12. DIELECTRIC WALL ACCELERATOR TECHNOLOGY

    Energy Technology Data Exchange (ETDEWEB)

    Sampayan, S; Caporaso, G; Chen, Y; Harris, J; Hawkins, S; Holmes, C; Nelson, S; Poole, B; Rhodes, M; Sanders, D; Sullivan, J; Wang, L; Watson, J

    2007-10-18

    The dielectric wall accelerator (DWA) is a compact pulsed power device where the pulse forming lines, switching, and vacuum wall are integrated into a single compact geometry. For this effort, we initiated a extensive compact pulsed power development program and have pursued the study of switching (gas, oil, laser induced surface flashover and photoconductive), dielectrics (ceramics and nanoparticle composites), pulse forming line topologies (asymmetric and symmetric Blumleins and zero integral pulse forming lines), and multilayered vacuum insulator (HGI) technology. Finally, we fabricated an accelerator cell for test on ETAII (a 5.5 MeV, 2 kA, 70 ns pulsewidth electron beam accelerator). We review our past results and report on the progress of accelerator cell testing.

  13. Rejuvenating CERN's Accelerators

    CERN Multimedia

    2004-01-01

    In the coming years and especially in 2005, CERN's accelerators are going to receive an extensive renovation programme to ensure they will perform reliably and effectively when the LHC comes into service.

  14. SPS accelerating cavity

    CERN Multimedia

    CERN PhotoLab

    1983-01-01

    View towards the downstream end of one of the SPS accelerating cavities (200 MHz, travelling wave structure). See 7603195 and 8011289 for more details, 7411032 for the travelling wave structure, and also 8104138.

  15. Linear Accelerator (LINAC)

    Science.gov (United States)

    ... View full size with caption Related Articles and Media External Beam Therapy (EBT) Intensity-Modulated Radiation Therapy (IMRT) Image-guided Radiation Therapy (IGRT) Stereotactic Radiosurgery (SRS) and Stereotactic Body Radiotherapy (SBRT) Images related to Linear Accelerator Sponsored ...

  16. Joint International Accelerator School

    CERN Multimedia

    CERN Accelerator School

    2014-01-01

    The CERN and US Particle Accelerator Schools recently organised a Joint International Accelerator School on Beam Loss and Accelerator Protection, held at the Hyatt Regency Hotel, Newport Beach, California, USA from 5-14 November 2014. This Joint School was the 13th in a series of such schools, which started in 1985 and also involves the accelerator communities in Japan and Russia.   Photo courtesy of Alfonse Pham, Michigan State University.   The school attracted 58 participants representing 22 different nationalities, with around half from Europe and the other half from Asia and the Americas. The programme comprised 26 lectures, each of 90 minutes, and 13 hours of case study. The students were given homework each day and had an opportunity to sit a final exam, which counted towards university credit. Feedback from the participants was extremely positive, praising the expertise and enthusiasm of the lecturers, as well as the high standard and quality of their lectures. Initial dis...

  17. Amps particle accelerator definition study

    Science.gov (United States)

    Sellen, J. M., Jr.

    1975-01-01

    The Particle Accelerator System of the AMPS (Atmospheric, Magnetospheric, and Plasmas in Space) payload is a series of charged particle accelerators to be flown with the Space Transportation System Shuttle on Spacelab missions. In the configuration presented, the total particle accelerator system consists of an energetic electron beam, an energetic ion accelerator, and both low voltage and high voltage plasma acceleration devices. The Orbiter is illustrated with such a particle accelerator system.

  18. LHCb GPU Acceleration Project

    CERN Document Server

    AUTHOR|(SzGeCERN)744808; Campora Perez, Daniel Hugo; Neufeld, Niko; Vilasis Cardona, Xavier

    2016-01-01

    The LHCb detector is due to be upgraded for processing high-luminosity collisions, which will increase the load on its computation infrastructure from 100 GB/s to 4 TB/s, encouraging us to look for new ways of accelerating the Online reconstruction. The Coprocessor Manager is our new framework for integrating LHCb’s existing computation pipelines with massively parallel algorithms running on GPUs and other accelerators. This paper describes the system and analyzes its performance.

  19. Accelerating News Issue 2

    CERN Document Server

    Kahle, K; Wildner, E

    2012-01-01

    In this summer issue we look at how developments in collimator materials could have applications in aerospace and beyond, and how Polish researchers are harnessing accelerators for medical and industrial uses. We see how the LHC luminosity upgrade is linking with European industry and US researchers, and how the neutrino oscillation community is progressing. We find out the mid-term status of TIARA-PP and how it is mapping European accelerator education resources.

  20. Accelerated Evidence Search Report

    Science.gov (United States)

    2014-07-01

    Accelerated Evidence Search Report IMPORTANT INFORMATIVE STATEMENTS Accelerated Multi-Camera Evidence Search and Retrieval CSSP Project #: CSSP -2013...CD-1063 was supported by the Canadian Safety and Security Program ( CSSP ) which is led by Defence Research and Development Canada’s Centre for...Border Technology Division The CSSP is a federally-funded program to strengthen Canada’s ability to anticipate, prevent/mitigate, prepare for, respond to

  1. Agility: Agent - Ility Architecture

    National Research Council Canada - National Science Library

    Thompson, Craig

    2002-01-01

    ...., object and web technologies). The objective of the Agility project is to develop an open agent grid architecture populated with scalable, deployable, industrial strength agent grid components, targeting the theme 'agents for the masses...

  2. Riot Control Agents

    Science.gov (United States)

    ... Submit What's this? Submit Button Facts About Riot Control Agents Interim document Recommend on Facebook Tweet Share Compartir FACT SHEET What riot control agents are Riot control agents (sometimes referred to ...

  3. Interacting agents in finance

    NARCIS (Netherlands)

    Hommes, C.; Durlauf, S.N.; Blume, L.E.

    2008-01-01

    Interacting agents in finance represent a behavioural, agent-based approach in which financial markets are viewed as complex adaptive systems consisting of many boundedly rational agents interacting through simple heterogeneous investment strategies, constantly adapting their behaviour in response

  4. Small type accelerator. Try for accelerator driven system

    CERN Document Server

    Mori, Y

    2003-01-01

    FFAG (Fixed-field alternating gradient) accelerator for accelerator driven subcritical reactor, which aims to change from long-lived radioactive waste to short-lived radioactivity, is introduced. It is ring accelerator. The performance needed is proton as accelerator particle, 10MW (total) beam power, about 1GeV beam energy, >30% power efficiency and continuous beam. The feature of FFAG accelerator is constant magnetic field. PoP (Proof-of-principle)-FFAG accelerator, radial type, was run at first in Japan in 2000. The excursion is about some ten cm. In principle, beam can be injected and extracted at any place of ring. The 'multi-fish' acceleration can accelerate beams to 100% duty by repeating acceleration. 150MeV-FFAG accelerator has been started since 2001. It tried to practical use, for example, treatment of cancer. (S.Y.)

  5. Accelerators in Science and Technology

    CERN Document Server

    Kailas, S

    2002-01-01

    Accelerators built for basic research in frontier areas of science have become important and inevitable tools in many areas of science and technology. Accelerators are examples of science driven high technology development. Accelerators are used for a wide ranging applications, besides basic research. Accelerator based multidisciplinary research holds great promise

  6. Plasma-based accelerator structures

    Energy Technology Data Exchange (ETDEWEB)

    Schroeder, Carl B. [Univ. of California, Berkeley, CA (United States)

    1999-12-01

    Plasma-based accelerators have the ability to sustain extremely large accelerating gradients, with possible high-energy physics applications. This dissertation further develops the theory of plasma-based accelerators by addressing three topics: the performance of a hollow plasma channel as an accelerating structure, the generation of ultrashort electron bunches, and the propagation of laser pulses is underdense plasmas.

  7. Particle accelerator physics

    CERN Document Server

    Wiedemann, Helmut

    2007-01-01

    Particle Accelerator Physics is an in-depth and comprehensive introduction to the field of high-energy particle acceleration and beam dynamics. Part I gathers the basic tools, recalling the essentials of electrostatics and electrodynamics as well as of particle dynamics in electromagnetic fields. Part II is an extensive primer in beam dynamics, followed in Part III by the introduction and description of the main beam parameters. Part IV is devoted to the treatment of perturbations in beam dynamics. Part V discusses the details of charged particle accleration. Part VI and Part VII introduce the more advanced topics of coupled beam dynamics and the description of very intense beams. Part VIII is an exhaustive treatment of radiation from accelerated charges and introduces important sources of coherent radiation such as synchrotrons and free-electron lasers. Part IX collects the appendices gathering useful mathematical and physical formulae, parameters and units. Solutions to many end-of-chapter problems are give...

  8. Quasar Jet Acceleration

    Science.gov (United States)

    Polito, Nicholas; Hough, David

    2009-10-01

    We observed radio jets in six lobe-dominated quasars (LDQs) from 1995 to 2008 using the NRAO VLBA at 8.4 and 15 GHz. These observations have tracked jet component positions and velocities over that time period. There is a correlation between apparent jet speed and projected core distance in these LDQs at greater than 99 per cent confidence levels (Hough 2008, Extragalactic Jets, eds: Rector and DeYoung, ASP, p. 274). Four of our sources show this effect particularly strongly. We only tracked single jet components over relatively short distances, but the assumption of a unique velocity profile allows us to study component motion on an effective timescale of approximately 20-50 years. Results for 3C207 and 3C263 show a good fit using a constant acceleration model. The cause of such acceleration is still unknown, though ``magnetic acceleration'' by a gradient in magnetic field pressure is one possibility.

  9. Superconducting Accelerator Magnets

    CERN Document Server

    Mess, K H; Wolff, S

    1996-01-01

    The main topic of the book are the superconducting dipole and quadrupole magnets needed in high-energy accelerators and storage rings for protons, antiprotons or heavy ions. The basic principles of low-temperature superconductivity are outlined with special emphasis on the effects which are relevant for accelerator magnets. Properties and fabrication methods of practical superconductors are described. Analytical methods for field calculation and multipole expansion are presented for coils without and with iron yoke. The effect of yoke saturation and geometric distortions on field quality is studied. Persistent magnetization currents in the superconductor and eddy currents the copper part of the cable are analyzed in detail and their influence on field quality and magnet performance is investigated. Superconductor stability, quench origins and propagation and magnet protection are addressed. Some important concepts of accelerator physics are introduced which are needed to appreciate the demanding requirements ...

  10. Accelerating the culture change!

    Science.gov (United States)

    Klunk, S W; Panetta, J; Wooten, J

    1996-11-01

    Exide Electronics, a major supplier of uninterruptible power system equipment, embarked on a journey of changing a culture to improve quality, enhance customer responsiveness, and reduce costs. This case study examines the evolution of change over a period of seven years, with particular emphasis on the most recent years, 1992 through 1995. The article focuses on the Raleigh plant operations and describes how each succeeding year built on the successes and fixed the shortcomings of the prior years to accelerate the culture change, including corrective action and continuous improvement processes, organizational structures, expectations, goals, achievements, and pitfalls. The real challenge to changing the culture was structuring a dynamic approach to accelerate change! The presentation also examines how the evolutionary process itself can be created and accelerated through ongoing communication, regular feedback of progress and goals, constant evaluation and direction of the process, and measuring and paying for performance.

  11. Artificial seismic acceleration

    Science.gov (United States)

    Felzer, Karen R.; Page, Morgan T.; Michael, Andrew J.

    2015-01-01

    In their 2013 paper, Bouchon, Durand, Marsan, Karabulut, 3 and Schmittbuhl (BDMKS) claim to see significant accelerating seismicity before M 6.5 interplate mainshocks, but not before intraplate mainshocks, reflecting a preparatory process before large events. We concur with the finding of BDMKS that their interplate dataset has significantly more fore- shocks than their intraplate dataset; however, we disagree that the foreshocks are predictive of large events in particular. Acceleration in stacked foreshock sequences has been seen before and has been explained by the cascade model, in which earthquakes occasionally trigger aftershocks larger than themselves4. In this model, the time lags between the smaller mainshocks and larger aftershocks follow the inverse power law common to all aftershock sequences, creating an apparent acceleration when stacked (see Supplementary Information).

  12. Microelectromechanical acceleration-sensing apparatus

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Robb M. (Albuquerque, NM); Shul, Randy J. (Albuquerque, NM); Polosky, Marc A. (Albuquerque, NM); Hoke, Darren A. (Albuquerque, NM); Vernon, George E. (Rio Rancho, NM)

    2006-12-12

    An acceleration-sensing apparatus is disclosed which includes a moveable shuttle (i.e. a suspended mass) and a latch for capturing and holding the shuttle when an acceleration event is sensed above a predetermined threshold level. The acceleration-sensing apparatus provides a switch closure upon sensing the acceleration event and remains latched in place thereafter. Examples of the acceleration-sensing apparatus are provided which are responsive to an acceleration component in a single direction (i.e. a single-sided device) or to two oppositely-directed acceleration components (i.e. a dual-sided device). A two-stage acceleration-sensing apparatus is also disclosed which can sense two acceleration events separated in time. The acceleration-sensing apparatus of the present invention has applications, for example, in an automotive airbag deployment system.

  13. Monoenergetic laser wakefield acceleration

    Directory of Open Access Journals (Sweden)

    N. E. Andreev

    2000-02-01

    Full Text Available Three dimensional test particle simulations are applied to optimization of the plasma-channeled laser wakefield accelerator (LWFA operating in a weakly nonlinear regime. Electron beam energy spread, emittance, and luminosity depend upon the proportion of the electron bunch size to the plasma wavelength. This proportion tends to improve with the laser wavelength increase. We simulate a prospective two-stage ∼1GeV LWFA with controlled energy spread and emittance. The input parameters correspond to realistic capabilities of the BNL Accelerator Test Facility that features a picosecond-terawatt CO_{2} laser and a high-brightness electron gun.

  14. Shielding high energy accelerators

    CERN Document Server

    Stevenson, Graham Roger

    2001-01-01

    After introducing the subject of shielding high energy accelerators, point source, line-of-sight models, and in particular the Moyer model. are discussed. Their use in the shielding of proton and electron accelerators is demonstrated and their limitations noted. especially in relation to shielding in the forward direction provided by large, flat walls. The limitations of reducing problems to those using it cylindrical geometry description are stressed. Finally the use of different estimators for predicting dose is discussed. It is suggested that dose calculated from track-length estimators will generally give the most satisfactory estimate. (9 refs).

  15. Accelerating News Issue 4

    CERN Document Server

    Szeberenyi, A; Wildner, E

    2012-01-01

    In this winter issue, we are very pleased to announce the approval of EuCARD-2 by the European Commission. We look at the conclusions of EUROnu in proposing future neutrino facilities at CERN, a new milestone reached by CLIC and progress on the SPARC upgrade using C-band technology. We also report on recent events: second Joint HiLumi LHC-LARP Annual Meeting and workshop on Superconducting technologies for the Next Generation of Accelerators aiming at closer collaboration with industry. The launch of the Accelerators for Society brochure is also highlighted.

  16. Accelerated tests of coil coatings

    Directory of Open Access Journals (Sweden)

    Rosales, B. M.

    2003-12-01

    Full Text Available Accelerated laboratory tests on 12 materials in study in the Subgroup 6 of the PATINA Network (CYTED, are discussed for different exposition periods in salt spray, SO2 and Prohesion chambers. International standards used to evaluate failures caused by the different aggressive agents of these laboratory tests are the same as those applied for outdoor expositions. The results exposed contribute to a better understanding of the mechanisms occurred in the diverse natural environments, being mentioned the main analogies and differences respect to factors affecting natural tests. They also allowed to evidence the advantages and limitations in the application of these tests during several days, as compared to the years required to attain similar failure magnitudes through outdoor tests.

    En este trabajo se discuten los ensayos de laboratorio acelerados, realizados sobre 12 materiales de estudio en el Subgrupo 6 de la Red PATINA (CYTED, a diferentes periodos de exposición en cámaras de niebla salina, SO2 y Prohesion. Se utilizaron las normas internacionales para evaluar los fallos causados por los diferentes agentes agresivos de estos ensayos de laboratorio, las cuales se aplican también para los ensayos de exposición a la intemperie. Los resultados expuestos contribuyen a una mejor comprensión de los mecanismos ocurridos en los diversos ambientes naturales, mencionándose las principales analogías y diferencias respecto de los factores que afectan los ensayos naturales. También permitieron evidenciar las ventajas y limitaciones en la aplicación de estos ensayos durante varios días, en comparación con los años requeridos para alcanzar magnitudes de fallos similares por medio de ensayos a intemperie.

  17. Laser Wakefield Accelerators

    OpenAIRE

    Najmudin, Z.

    2017-01-01

    The one-dimensional wakefield generation equations are solved for increasing levels of non-linearity, to demonstrate how they contribute to the overall behaviour of a non-linear wakefield in a plasma. The effect of laser guiding is also studied as a way to increase the interaction length of a laser wakefield accelerator.

  18. The CERN Accelerator School

    CERN Multimedia

    2016-01-01

      Introduction to accelerator physics This course will take place in Istanbul, Turkey, from 18 to 30 September 2016. It is now open for registration, and further information can be found here: http://cas.web.cern.ch/cas/Turkey-2016/Turkey-advert.html

  19. SPS accelerating cavity

    CERN Multimedia

    CERN PhotoLab

    1983-01-01

    See photo 8302397: View from the downstream end of one of the SPS accelerating cavities (200 MHz, travelling wave structure). See 7603195 and 8011289 for more details, 7411032 for the travelling wave structure, and also 8104138. Giacomo Primadei stands on the left.

  20. The CERN accelerator complex

    CERN Multimedia

    Mobs, Esma Anais

    2016-01-01

    The LHC is the last ring (dark blue line) in a complex chain of particle accelerators. The smaller machines are used in a chain to help boost the particles to their final energies and provide beams to a whole set of smaller experiments, which also aim to uncover the mysteries of the Universe.

  1. The CERN accelerator complex

    CERN Multimedia

    Haffner, Julie

    2013-01-01

    The LHC is the last ring (dark grey line) in a complex chain of particle accelerators. The smaller machines are used in a chain to help boost the particles to their final energies and provide beams to a whole set of smaller experiments, which also aim to uncover the mysteries of the Universe.

  2. The CERN accelerator complex

    CERN Multimedia

    Christiane Lefèvre

    2008-01-01

    The LHC is the last ring (dark grey line) in a complex chain of particle accelerators. The smaller machines are used in a chain to help boost the particles to their final energies and provide beams to a whole set of smaller experiments, which also aim to uncover the mysteries of the Universe.

  3. Dissociation by acceleration

    NARCIS (Netherlands)

    Peeters, K.; Zamaklar, m.

    2008-01-01

    We show that mesons, described using rotating relativistic strings in a holographic setup, undergo dissociation when their acceleration 'a' exceeds a value which scales with the angular momentum 'J' as a_max ~ \\sqrt{T_s/J}, where 'T_s' is the string tension.

  4. SPS accelerating cavity

    CERN Multimedia

    CERN PhotoLab

    1980-01-01

    One of the SPS acceleration cavities (200 MHz, travelling wave structure). On the ceiling one sees the coaxial transmission line which feeds the power from the amplifier, located in a surface building above, to the upstream end of the cavity. See 7603195 for more details, 7411032 for the travelling wave structure, and also 8104138, 8302397.

  5. SPS accelerating cavity

    CERN Multimedia

    CERN PhotoLab

    1981-01-01

    One of the SPS accelerating cavities (200 MHz, travelling wave structure). The power that is fed into the upstream end of the cavity is extracted at the downstream end and sent into a dump load. See 7603195 for more details, 7411032 for the travelling wave structure, and also 8011289, 8302397.

  6. The CERN Accelerator School

    CERN Multimedia

    2016-01-01

    Introduction to accelerator physics This course will take place in Budapest, Hungary, from 2 to 14 October 2016. It is now open for registration and further information can be found at: http://cas.web.cern.ch/cas/Hungary2016/Hungary-advert.html and http://indico.cern.ch/event/532397/.

  7. Angular Accelerating White Light

    CSIR Research Space (South Africa)

    Dudley, Angela L

    2015-08-01

    Full Text Available Significant interest has been devoted to tailoring optical fields that transversely accelerate during propagation in the form of Airy, Weber and Mathieu beams. In this work, the authors introduce a new type of optical field that exhibits controlled...

  8. Neurodegeneration in accelerated aging.

    Science.gov (United States)

    Scheibye-Knudsen, Moren

    2016-11-01

    The growing proportion of elderly people represents an increasing economic burden, not least because of age-associated diseases that pose a significant cost to the health service. Finding possible interventions to age-associated disorders therefore have wide ranging implications. A number of genetically defined accelerated aging diseases have been characterized that can aid in our understanding of aging. Interestingly, all these diseases are associated with defects in the maintenance of our genome. A subset of these disorders, Cockayne syndrome, Xeroderma pigmentosum group A and ataxia-telangiectasia, show neurological involvement reminiscent of what is seen in primary human mitochondrial diseases. Mitochondria are the power plants of the cells converting energy stored in oxygen, sugar, fat, and protein into ATP, the energetic currency of our body. Emerging evidence has linked this organelle to aging and finding mitochondrial dysfunction in accelerated aging disorders thereby strengthens the mitochondrial theory of aging. This theory states that an accumulation of damage to the mitochondria may underlie the process of aging. Indeed, it appears that some accelerated aging disorders that show neurodegeneration also have mitochondrial dysfunction. The mitochondrial alterations may be secondary to defects in nuclear DNA repair. Indeed, nuclear DNA damage may lead to increased energy consumption, alterations in mitochondrial ATP production and defects in mitochondrial recycling, a term called mitophagy. These changes may be caused by activation of poly-ADP-ribose-polymerase 1 (PARP1), an enzyme that responds to DNA damage. Upon activation PARP1 utilizes key metabolites that attenuate pathways that are normally protective for the cell. Notably, pharmacological inhibition of PARP1 or reconstitution of the metabolites rescues the changes caused by PARP1 hyperactivation and in many cases reverse the phenotypes associated with accelerated aging. This implies that modulation

  9. Relativity and accelerator engineering

    Energy Technology Data Exchange (ETDEWEB)

    Geloni, Gianluca [European XFEL GmbH, Schenefeld (Germany); Kocharyan, Vitali; Saldin, Evgeni [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

    2017-09-15

    From a geometrical viewpoint, according to the theory of relativity, space and time constitute a four-dimensional continuum with pseudo-Euclidean structure. This has recently begun to be a practically important statement in accelerator physics. An X-ray Free Electron Laser (XFEL) is in fact the best, exciting example of an engineering system where improvements in accelerator technology makes it possible to develop ultrarelativistic macroscopic objects with an internal fine structure, and the theory of relativity plays an essential role in their description. An ultrarelativistic electron bunch modulated at nanometer-scale in XFELs has indeed a macroscopic finite-size of order of 10 μm. Its internal, collective structure is characterized in terms of a wave number vector. Here we will show that a four-dimensional geometrical approach, unusual in accelerator physics, is needed to solve problems involving the emission of radiation from an ultrarelativistic modulated electron beam accelerating along a curved trajectory. We will see that relativistic kinematics enters XFEL physics in a most fundamental way through the so-called Wigner rotation of the modulation wave number vector, which is closely associated to the relativity of simultaneity. If not taken into account, relativistic kinematics effects would lead to a strong qualitative disagreement between theory and experiments. In this paper, several examples of relativistic kinematics effects, which are important for current and future XFEL operation, are studied. The theory of relativity is applied by providing details of the clock synchronization procedure within the laboratory frame. This approach, exploited here but unusual in literature, is rather ''practical'', and should be acceptable to accelerator physicists.

  10. Nonlinear dynamics in particle accelerators

    CERN Document Server

    Dilão, Rui

    1996-01-01

    This book is an introductory course to accelerator physics at the level of graduate students. It has been written for a large audience which includes users of accelerator facilities, accelerator physicists and engineers, and undergraduates aiming to learn the basic principles of construction, operation and applications of accelerators.The new concepts of dynamical systems developed in the last twenty years give the theoretical setting to analyse the stability of particle beams in accelerator. In this book a common language to both accelerator physics and dynamical systems is integrated and dev

  11. Accelerator research studies

    Energy Technology Data Exchange (ETDEWEB)

    1992-01-01

    The Accelerator Research Studies program at the University of Maryland, sponsored by the Department of Energy under grant number DE-FG05-91ER40642, is currently in the first year of a three-year funding cycle. The program consists of the following three tasks: TASK A, Study of Transport and Longitudinal Compression of Intense, High-Brightness Beams, TASK B, Study of Collective Ion Acceleration by Intense Electron Beams and Pseudospark Produced High Brightness Electron Beams; TASK C, Study of a Gyroklystron High-power Microwave Source for Linear Colliders. In this report we document the progress that has been made during the past year for each of the three tasks.

  12. Accelerating time to benefit

    DEFF Research Database (Denmark)

    Svejvig, Per; Geraldi, Joana; Grex, Sara

    Despite the ubiquitous pressure for speed, our approaches to accelerate projects remain constrained to the old-fashioned understanding of the project as a vehicle to deliver products and services, not value. This article explores an attempt to accelerate time to benefit. We describe and deconstruct...... of the time. Although all cases valued speed and speed to benefit, and implemented most practices proposed by the methodology, only three of the five projects were more successful in decreasing time to speed. Based on a multi-case study comparison between these five different projects and their respective...... the implementation of a large intervention undertaken in five project-based organizations in Denmark – the Project Half Double where the same project methodology has been applied in five projects, each of them in five distinct organizations in Denmark, as a bold attempt to realize double the benefit in half...

  13. accelerating cavity from LEP

    CERN Multimedia

    This is an accelerating cavity from LEP, with a layer of niobium on the inside. Operating at 4.2 degrees above absolute zero, the niobium is superconducting and carries an accelerating field of 6 million volts per metre with negligible losses. Each cavity has a surface of 6 m2. The niobium layer is only 1.2 microns thick, ten times thinner than a hair. Such a large area had never been coated to such a high accuracy. A speck of dust could ruin the performance of the whole cavity so the work had to be done in an extremely clean environment. These challenging requirements pushed European industry to new achievements. 256 of these cavities are now used in LEP to double the energy of the particle beams.

  14. Acceleration of microparticle

    CERN Document Server

    Shibata, H

    2002-01-01

    A microparticle (dust) ion source has been installed at the high voltage terminal of the 3.75 MV single ended Van de Graaff electrostatic accelerator and a beam line for microparticle experiments has been build at High Fluence Irradiation Facility (HIT) of Research Center for Nuclear Science and Technology, the University of Tokyo. Microparticle acceleration has been successful in obtaining expected velocities of 1-20 km/s or more for micron or submicron sized particles. Development of in situ dust detectors and analyzers on board satellites and spacecraft in the expected mass and velocity range of micrometeoroids and investigation of hypervelocity impact phenomena by using time of flight mass spectrometry, impact flash or luminescence measurement and scanning electron or laser microscope observation for metals, ceramics, polymers and semiconductors bombarded by micron-sized particles were started three years ago. (author)

  15. Lectures in accelerator theory

    CERN Document Server

    Month, M

    1981-01-01

    Accelerator theory is a broad area of study involving the behaviour of particle beams. Out of the many categories, the author has chosen to describe three phenomena taken from (1) the theory of single particle motion in nonlinear fields; (2) the theory of high intensity coherent motion and; (3) the theory of current accumulation. He deals with the behaviour of particles in the nonlinear field arising from the electromagnetic interaction of colliding beams. An analysis of the development of traveling waves on particle beams is presented. The situation studied is that of a uniform beam current in a circular accelerator and the excitation for the coherent motion is induced by the resistivity of the vacuum chamber wall. A description of the current accumulation process used at the proton storage rings at CERN (ISR) is given. (0 refs).

  16. Accelerators for Cancer Therapy

    Science.gov (United States)

    Lennox, Arlene J.

    2000-05-30

    The vast majority of radiation treatments for cancerous tumors are given using electron linacs that provide both electrons and photons at several energies. Design and construction of these linacs are based on mature technology that is rapidly becoming more and more standardized and sophisticated. The use of hadrons such as neutrons, protons, alphas, or carbon, oxygen and neon ions is relatively new. Accelerators for hadron therapy are far from standardized, but the use of hadron therapy as an alternative to conventional radiation has led to significant improvements and refinements in conventional treatment techniques. This paper presents the rationale for radiation therapy, describes the accelerators used in conventional and hadron therapy, and outlines the issues that must still be resolved in the emerging field of hadron therapy.

  17. Hardware Accelerated Simulated Radiography

    Energy Technology Data Exchange (ETDEWEB)

    Laney, D; Callahan, S; Max, N; Silva, C; Langer, S; Frank, R

    2005-04-12

    We present the application of hardware accelerated volume rendering algorithms to the simulation of radiographs as an aid to scientists designing experiments, validating simulation codes, and understanding experimental data. The techniques presented take advantage of 32 bit floating point texture capabilities to obtain validated solutions to the radiative transport equation for X-rays. An unsorted hexahedron projection algorithm is presented for curvilinear hexahedra that produces simulated radiographs in the absorption-only regime. A sorted tetrahedral projection algorithm is presented that simulates radiographs of emissive materials. We apply the tetrahedral projection algorithm to the simulation of experimental diagnostics for inertial confinement fusion experiments on a laser at the University of Rochester. We show that the hardware accelerated solution is faster than the current technique used by scientists.

  18. Particle accelerator physics

    CERN Document Server

    Wiedemann, Helmut

    2015-01-01

    This book by Helmut Wiedemann is a well-established, classic text, providing an in-depth and comprehensive introduction to the field of high-energy particle acceleration and beam dynamics. The present 4th edition has been significantly revised, updated and expanded. The newly conceived Part I is an elementary introduction to the subject matter for undergraduate students. Part II gathers the basic tools in preparation of a more advanced treatment, summarizing the essentials of electrostatics and electrodynamics as well as of particle dynamics in electromagnetic fields. Part III is an extensive primer in beam dynamics, followed, in Part IV, by an introduction and description of the main beam parameters and including a new chapter on beam emittance and lattice design. Part V is devoted to the treatment of perturbations in beam dynamics. Part VI then discusses the details of charged particle acceleration. Parts VII and VIII introduce the more advanced topics of coupled beam dynamics and describe very intense bea...

  19. Accelerated plate tectonics.

    Science.gov (United States)

    Anderson, D L

    1975-03-21

    The concept of a stressed elastic lithospheric plate riding on a viscous asthenosphere is used to calculate the recurrence interval of great earthquakes at convergent plate boundaries, the separation of decoupling and lithospheric earthquakes, and the migration pattern of large earthquakes along an arc. It is proposed that plate motions accelerate after great decoupling earthquakes and that most of the observed plate motions occur during short periods of time, separated by periods of relative quiescence.

  20. Accelerating regular polygon beams.

    Science.gov (United States)

    Barwick, Shane

    2010-12-15

    Beams that possess high-intensity peaks that follow curved paths of propagation under linear diffraction have recently been shown to have a multitude of interesting uses. In this Letter, a family of phase-only masks is derived, and each mask gives rise to multiple accelerating intensity maxima. The curved paths of the peaks can be described by the vertices of a regular polygon that is centered on the optic axis and expands with propagation.

  1. Accelerating News Issue 3

    CERN Document Server

    Kahle, K; Tanguy, C; Wildner, E

    2012-01-01

    This summer saw CERN announce to a worldwide audience the discovery of a Higgs-like boson, so this issue takes a look at the machine behind the discovery, the LHC, as well as future plans for a possible Higgs factory in the form of LEP3. Looking ahead too are European strategies for particle physics and accelerator-based neutrino physics. In addition, taking stock of the work so far, HiLumi LHC and EuCARD showcase their latest results.

  2. Particle Accelerator Focus Automation

    Science.gov (United States)

    Lopes, José; Rocha, Jorge; Redondo, Luís; Cruz, João

    2017-08-01

    The Laboratório de Aceleradores e Tecnologias de Radiação (LATR) at the Campus Tecnológico e Nuclear, of Instituto Superior Técnico (IST) has a horizontal electrostatic particle accelerator based on the Van de Graaff machine which is used for research in the area of material characterization. This machine produces alfa (He+) and proton (H+) beams of some μA currents up to 2 MeV/q energies. Beam focusing is obtained using a cylindrical lens of the Einzel type, assembled near the high voltage terminal. This paper describes the developed system that automatically focuses the ion beam, using a personal computer running the LabVIEW software, a multifunction input/output board and signal conditioning circuits. The focusing procedure consists of a scanning method to find the lens bias voltage which maximizes the beam current measured on a beam stopper target, which is used as feedback for the scanning cycle. This system, as part of a wider start up and shut down automation system built for this particle accelerator, brings great advantages to the operation of the accelerator by turning it faster and easier to operate, requiring less human presence, and adding the possibility of total remote control in safe conditions.

  3. The Silicon Lattice Accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Spencer, J

    2003-11-24

    Previously, the generalized luminosity L was defined and calculated for all incident channels based on an NLC e{sup +}e{sup -} design. Alternatives were then considered to improve the differing beam-beam effects in the e{sup -}e{sup -}, e{gamma} and {gamma}{gamma} channels. One example was tensor beams composed of bunchlets n{sub ijk} implemented with a laser-driven, silicon accelerator based on micromachining techniques. Problems were considered and expressions given for radiative broadening due to bunchlet manipulation near the final focus to optimize luminosity via charge enhancement, neutralization or bunch shaping. Because the results were promising, we explore fully integrated structures that include sources, optics (for both light and particles) and acceleration in a common format--an accelerator-on-chip. Acceptable materials (and wavelengths) must allow velocity synchronism between many laser and electron pulses with optimal efficiency in high radiation environments. There are obvious control and cost advantages that accrue from using silicon structures if radiation effects can be made acceptable and the structures fabricated. Tests related to deep etching, fabrication and radiation effects on candidate amorphous and crystalline materials indicate Si(1.2 < {lambda}{sub L} < 10 {micro}m) and fused c-SiO{sub 2}(0.3 < {lambda}{sub L} < 4 {micro}m) to be ideal.

  4. Acceleration during magnetic reconnection

    Energy Technology Data Exchange (ETDEWEB)

    Beresnyak, Andrey [Los Alamos National Laboratory; Li, Hui [Los Alamos National Laboratory

    2015-07-16

    The presentation begins with colorful depictions of solar x-ray flares and references to pulsar phenomena. Plasma reconnection is complex, could be x-point dominated or turbulent, field lines could break due to either resistivity or non-ideal effects, such as electron pressure anisotropy. Electron acceleration is sometimes observed, and sometimes not. One way to study this complex problem is to have many examples of the process (reconnection) and compare them; the other way is to simplify and come to something robust. Ideal MHD (E=0) turbulence driven by magnetic energy is assumed, and the first-order acceleration is sought. It is found that dissipation in big (length >100 ion skin depths) current sheets is universal and independent on microscopic resistivity and the mean imposed field; particles are regularly accelerated while experiencing curvature drift in flows driven by magnetic tension. One example of such flow is spontaneous reconnection. This explains hot electrons with a power-law tail in solar flares, as well as ultrashort time variability in some astrophysical sources.

  5. Particle Accelerator Focus Automation

    Directory of Open Access Journals (Sweden)

    Lopes José

    2017-08-01

    Full Text Available The Laboratório de Aceleradores e Tecnologias de Radiação (LATR at the Campus Tecnológico e Nuclear, of Instituto Superior Técnico (IST has a horizontal electrostatic particle accelerator based on the Van de Graaff machine which is used for research in the area of material characterization. This machine produces alfa (He+ and proton (H+ beams of some μA currents up to 2 MeV/q energies. Beam focusing is obtained using a cylindrical lens of the Einzel type, assembled near the high voltage terminal. This paper describes the developed system that automatically focuses the ion beam, using a personal computer running the LabVIEW software, a multifunction input/output board and signal conditioning circuits. The focusing procedure consists of a scanning method to find the lens bias voltage which maximizes the beam current measured on a beam stopper target, which is used as feedback for the scanning cycle. This system, as part of a wider start up and shut down automation system built for this particle accelerator, brings great advantages to the operation of the accelerator by turning it faster and easier to operate, requiring less human presence, and adding the possibility of total remote control in safe conditions.

  6. Optimizing accelerator technology

    CERN Document Server

    Katarina Anthony

    2012-01-01

    A new EU-funded research and training network, oPAC, is bringing together 22 universities, research centres and industry partners to optimize particle accelerator technology. CERN is one of the network’s main partners and will host 5 early-stage researchers in the BE department.   A diamond detector that will be used for novel beam diagnostics applications in the oPAC project based at CIVIDEC. (Image courtesy of CIVIDEC.) As one of the largest Marie Curie Initial Training Networks ever funded by the EU – to the tune of €6 million – oPAC extends well beyond the particle physics community. “Accelerator physics has become integral to research in almost every scientific discipline – be it biology and life science, medicine, geology and material science, or fundamental physics,” explains Carsten P. Welsch, oPAC co-ordinator based at the University of Liverpool. “By optimizing the operation of accelerators, all of these...

  7. Introduction to Microwave Linear [Accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Whittum, David H

    1999-01-04

    The elements of microwave linear accelerators are introduced starting with the principles of acceleration and accelerating structures. Considerations for microwave structure modeling and design are developed from an elementary point of view. Basic elements of microwave electronics are described for application to the accelerator circuit and instrumentation. Concepts of beam physics are explored together with examples of common beamline instruments. Charged particle optics and lattice diagnostics are introduced. Considerations for fixed-target and colliding-beam experimentation are summarized.

  8. Taskable Reactive Agent Communities

    National Research Council Canada - National Science Library

    Myers, Karen

    2002-01-01

    The focus of Taskable Reactive Agent Communities (TRAC) project was to develop mixed-initiative technology to enable humans to supervise and manage teams of agents as they perform tasks in dynamic environments...

  9. Mobile Agents Applications.

    Science.gov (United States)

    Martins, Rosane Maria; Chaves, Magali Ribeiro; Pirmez, Luci; Rust da Costa Carmo, Luiz Fernando

    2001-01-01

    Discussion of the need to filter and retrieval relevant information from the Internet focuses on the use of mobile agents, specific software components which are based on distributed artificial intelligence and integrated systems. Surveys agent technology and discusses the agent building package used to develop two applications using IBM's Aglet…

  10. Users, Bystanders and Agents

    DEFF Research Database (Denmark)

    Krummheuer, Antonia Lina

    2015-01-01

    Human-agent interaction (HAI), especially in the field of embodied conversational agents (ECA), is mainly construed as dyadic communication between a human user and a virtual agent. This is despite the fact that many application scenarios for future ECAs involve the presence of others. This paper...

  11. Reasoning about emotional agents

    NARCIS (Netherlands)

    Meyer, J.-J.

    In this paper we discuss the role of emotions in artificial agent design, and the use of logic in reasoning about the emotional or affective states an agent can reside in. We do so by extending the KARO framework for reasoning about rational agents appropriately. In particular we formalize in

  12. Culturally Aware Agent Communication

    DEFF Research Database (Denmark)

    Rehm, Matthias; Nakano, Yukiko; Koda, Tomoko

    2012-01-01

    Agent based interaction in the form of Embodied Conversational Agents (ECAs) has matured over the last decade and agents have become more and more sophisticated in terms of their verbal and nonverbal behavior like facial expressions or gestures. Having such “natural” communication channels...

  13. Agents modeling agents in information economies

    Energy Technology Data Exchange (ETDEWEB)

    Vidal, J.M.; Durfee, E.H. [Univ. of Michigan, Ann Arbor, MI (United States)

    1996-12-31

    Our goal is to design and build agents that act intelligently when placed in an agent-based information economy, where agents buy and sell services (e.g. thesaurus, search, task planning services, etc.). The economy we are working in is the University of Michigan Digital Library (UMDL), a large scale multidisciplinary effort to build an infrastructure for the delivery of library services. In contrast with a typical economy, an information economy deals in goods and services that are often derived from unique sources (authors, analysts, etc.), so that many goods and services are not interchangeable. Also, the cost of replicating and transporting goods is usually negligible, and the quality of goods and services is difficult to measure objectively: even two sources with essentially the same information might appeal to different audiences. Thus, each agent has its own assessment of the quality of goods and services delivered.

  14. A review of imaging agent development.

    Science.gov (United States)

    Agdeppa, Eric D; Spilker, Mary E

    2009-06-01

    This educational review highlights the processes, opportunities, and challenges encountered in the discovery and development of imaging agents, mainly positron emission tomography and single-photon emission computed tomography tracers. While the development of imaging agents parallels the drug development process, unique criteria are needed to identify opportunities for new agents. Imaging agent development has the flexibility to pursue functional or nonfunctional targets as long as they play a role in the specific disease or mechanism of interest and meet imageability requirements. However, their innovation is tempered by relatively small markets for diagnostic imaging agents, intellectual property challenges, radiolabeling constraints, and adequate target concentrations for imaging. At the same time, preclinical imaging is becoming a key translational tool for proof of mechanism and concept studies. Pharmaceutical and imaging industries face a common bottleneck in the form of the limited number of trials one company can possibly perform. However, microdosing and theranostics are evidence that partnerships between pharmaceutical and imaging companies can accelerate clinical translation of tracers and therapeutic interventions. This manuscript will comment on these aspects to provide an educational review of the discovery and development processes for imaging agents.

  15. APT accelerator. Topical report

    Energy Technology Data Exchange (ETDEWEB)

    Lawrence, G.; Rusthoi, D. [comp.] [ed.

    1995-03-01

    The Accelerator Production of Tritium (APT) project, sponsored by Department of Energy Defense Programs (DOE/DP), involves the preconceptual design of an accelerator system to produce tritium for the nation`s stockpile of nuclear weapons. Tritium is an isotope of hydrogen used in nuclear weapons, and must be replenished because of radioactive decay (its half-life is approximately 12 years). Because the annual production requirements for tritium has greatly decreased since the end of the Cold War, an alternative approach to reactors for tritium production, based on a linear accelerator, is now being seriously considered. The annual tritium requirement at the time this study was undertaken (1992-1993) was 3/8 that of the 1988 goal, usually stated as 3/8-Goal. Continued reduction in the number of weapons in the stockpile has led to a revised (lower) production requirement today (March, 1995). The production requirement needed to maintain the reduced stockpile, as stated in the recent Nuclear Posture Review (summer 1994) is approximately 3/16-Goal, half the previous level. The Nuclear Posture Review also requires that the production plant be designed to accomodate a production increase (surge) to 3/8-Goal capability within five years, to allow recovery from a possible extended outage of the tritium plant. A multi-laboratory team, collaborating with several industrial partners, has developed a preconceptual APT design for the 3/8-Goal, operating at 75% capacity. The team has presented APT as a promising alternative to the reactor concepts proposed for Complex-21. Given the requirements of a reduced weapons stockpile, APT offers both significant safety, environmental, and production-fexibility advantages in comparison with reactor systems, and the prospect of successful development in time to meet the US defense requirements of the 21st Century.

  16. VLHC accelerator physics

    Energy Technology Data Exchange (ETDEWEB)

    Michael Blaskiewicz et al.

    2001-11-01

    A six-month design study for a future high energy hadron collider was initiated by the Fermilab director in October 2000. The request was to study a staged approach where a large circumference tunnel is built that initially would house a low field ({approx}2 T) collider with center-of-mass energy greater than 30 TeV and a peak (initial) luminosity of 10{sup 34} cm{sup -2}s{sup -1}. The tunnel was to be scoped, however, to support a future upgrade to a center-of-mass energy greater than 150 TeV with a peak luminosity of 2 x 10{sup 34} cm{sup -2} sec{sup -1} using high field ({approx} 10 T) superconducting magnet technology. In a collaboration with Brookhaven National Laboratory and Lawrence Berkeley National Laboratory, a report of the Design Study was produced by Fermilab in June 2001. 1 The Design Study focused on a Stage 1, 20 x 20 TeV collider using a 2-in-1 transmission line magnet and leads to a Stage 2, 87.5 x 87.5 TeV collider using 10 T Nb{sub 3}Sn magnet technology. The article that follows is a compilation of accelerator physics designs and computational results which contributed to the Design Study. Many of the parameters found in this report evolved during the study, and thus slight differences between this text and the Design Study report can be found. The present text, however, presents the major accelerator physics issues of the Very Large Hadron Collider as examined by the Design Study collaboration and provides a basis for discussion and further studies of VLHC accelerator parameters and design philosophies.

  17. Accelerated Innovation Pilot

    Science.gov (United States)

    Davis, Jeffrey

    2012-01-01

    Opportunities: I. Engage NASA team (examples) a) Research and technology calls . provide suggestions to AES, HRP, OCT. b) Use NASA@Work to solicit other ideas; (possibly before R+D calls). II. Stimulate collaboration (examples) a) NHHPC. b) Wharton Mack Center for Technological Innovation (Feb 2013). c) International ] DLR ] :envihab (July 2013). d) Accelerated research models . NSF, Myelin Repair Foundation. III. Engage public Prizes (open platform: InnoCentive, yet2.com, NTL; Rice Business Plan, etc.) IV. Use same methods to engage STEM.

  18. Accelerating abelian gauge dynamics

    CERN Document Server

    Adler, Stephen Louis

    1991-01-01

    In this paper, we suggest a new acceleration method for Abelian gauge theories based on linear transformations to variables which weight all length scales equally. We measure the autocorrelation time for the Polyakov loop and the plaquette at β=1.0 in the U(1) gauge theory in four dimensions, for the new method and for standard Metropolis updates. We find a dramatic improvement for the new method over the Metropolis method. Computing the critical exponent z for the new method remains an important open issue.

  19. Introduction to Accelerator Dynamics

    Science.gov (United States)

    Peggs, Stephen; Satogata, Todd

    2017-08-01

    Preface; 1. Introduction; 2. Linear motion; 3. Strong focusing transverse optics; 4. Longitudinal and off-momentum motion; 5. Action and emittance - one particle or many?; 6. Magnets; 7. RF cavities; 8. Linear errors and their correction; 9. Sextupoles, chromaticity and the Hénon map; 10. Octupoles, detuning and slow extraction; 11. Synchrotron radiation - classical damping; 12. Synchrotron radiation - quantum excitation; 13. Linacs - protons and ions; 14. Linacs - electrons; 15. The beam-beam interaction and 1-D resonances; 16. Routes to chaos; Appendix: selected formulae for accelerator design; References; Index.

  20. 2014 CERN Accelerator Schools

    CERN Multimedia

    2014-01-01

    A specialised school on Power Converters will be held in Baden, Switzerland, from 7 to 14 May 2014. Please note that the deadline for applications is 7 FEBRUARY 2014. A course on Introduction to Accelerator Physics will be held in Prague, Czech Republic, from 31 August to 12 September 2014. Applications are now open for this school; the application deadline is 25 APRIL 2014. Further information on these schools and other CAS events can be found on the CAS website and on the Indico page. For further information please contact Barbara.strasser@cern.ch

  1. Accelerator School Success

    CERN Multimedia

    2004-01-01

    Accelerator specialists don't grow on trees: training them is the job of the CERN Accelerator School (CAS). Group photo during visit to the Daresbury Laboratory. CAS and the CCLRC Daresbury Laboratory jointly organised a specialised school on Power Converters in Warrington, England from 12-18 May 2004. The last CAS Power Converter course was in 1990, so there was plenty of ground to cover. The challenging programme proposed a review of the state of the art and the latest developments in the field, including 30 hours of tuition. The school also included a visit to the CCLRC Daresbury laboratory, a one-day excursion to Liverpool and Chester and a themed (Welsh medieval) dinner at the school's closure. A record attendance of 91 students of more than 20 different nationalities included not only participants from Europe and North America but also from Armenia, Taiwan, India, Turkey, Iran and for the first time, fee-paying students from China and Australia. European industry showed a welcome and solid interest in...

  2. Broadband accelerator control network

    Energy Technology Data Exchange (ETDEWEB)

    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 (AG) 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.

  3. Acceleration in Linear and Circular Motion

    Science.gov (United States)

    Kellington, S. H.; Docherty, W.

    1975-01-01

    Describes the construction of a simple accelerometer and explains its use in demonstrating acceleration, deceleration, constant speed, measurement of acceleration, acceleration and the inclined plane and angular and radial acceleration. (GS)

  4. Accelerator Technology: Geodesy and Alignment for Particle Accelerators

    CERN Document Server

    Missiaen, D

    2013-01-01

    This document is part of Subvolume C 'Accelerators and Colliders' of Volume 21 'Elementary Particles' of Landolt-Börnstein - Group I 'Elementary Particles, Nuclei and Atoms'. It contains the the Section '8.9 Geodesy and Alignment for Particle Accelerators' of the Chapter '8 Accelerator Technology' with the content: 8.9 Geodesy and Alignment for Particle Accelerators 8.9.1 Introduction 8.9.2 Reference and Co-ordinate Systems 8.9.3 Definition of the Beam Line on the Accelerator Site 8.9.4 Geodetic Network 8.9.5 Tunnel Preliminary Works 8.9.6 The Alignment References 8.9.7 Alignment of Accelerator Components 8.9.8 Permanent Monitoring and Remote Alignment of Low Beta Quadrupoles 8.9.9 Alignment of Detector Components

  5. 2014 Joint International Accelerator School: Beam Loss and Accelerator Protection

    CERN Document Server

    JAS - Joint US-CERN-Japan-Russia Accelerator School

    2016-01-01

    Many particle accelerators operate with very high beam power and very high energy stored in particle beams as well as in magnet systems. In the future, the beam power in high intensity accelerators will further increase. The protection of the accelerator equipment from the consequences of uncontrolled release of the energy is essential. This was the motivation for organizing a first school on beam losses and accelerator protection (in general referred to as machine protection). During the school the methods and technologies to identify, mitigate, monitor and manage the technical risks associated with the operation of accelerators with high-power beams or subsystems with large stored energy were presented. At the completion of the school the participants should have been able to understand the physical phenomena that can damage machine subsystems or interrupt operations and to analyze an accelerator facility to produce a register of technical risks and the corresponding risk mitigation and management strategie...

  6. Accelerating Multiagent Reinforcement Learning by Equilibrium Transfer.

    Science.gov (United States)

    Hu, Yujing; Gao, Yang; An, Bo

    2015-07-01

    An important approach in multiagent reinforcement learning (MARL) is equilibrium-based MARL, which adopts equilibrium solution concepts in game theory and requires agents to play equilibrium strategies at each state. However, most existing equilibrium-based MARL algorithms cannot scale due to a large number of computationally expensive equilibrium computations (e.g., computing Nash equilibria is PPAD-hard) during learning. For the first time, this paper finds that during the learning process of equilibrium-based MARL, the one-shot games corresponding to each state's successive visits often have the same or similar equilibria (for some states more than 90% of games corresponding to successive visits have similar equilibria). Inspired by this observation, this paper proposes to use equilibrium transfer to accelerate equilibrium-based MARL. The key idea of equilibrium transfer is to reuse previously computed equilibria when each agent has a small incentive to deviate. By introducing transfer loss and transfer condition, a novel framework called equilibrium transfer-based MARL is proposed. We prove that although equilibrium transfer brings transfer loss, equilibrium-based MARL algorithms can still converge to an equilibrium policy under certain assumptions. Experimental results in widely used benchmarks (e.g., grid world game, soccer game, and wall game) show that the proposed framework: 1) not only significantly accelerates equilibrium-based MARL (up to 96.7% reduction in learning time), but also achieves higher average rewards than algorithms without equilibrium transfer and 2) scales significantly better than algorithms without equilibrium transfer when the state/action space grows and the number of agents increases.

  7. Moral actor, selfish agent.

    Science.gov (United States)

    Frimer, Jeremy A; Schaefer, Nicola K; Oakes, Harrison

    2014-05-01

    People are motivated to behave selfishly while appearing moral. This tension gives rise to 2 divergently motivated selves. The actor-the watched self-tends to be moral; the agent-the self as executor-tends to be selfish. Three studies present direct evidence of the actor's and agent's distinct motives. To recruit the self-as-actor, we asked people to rate the importance of various goals. To recruit the self-as-agent, we asked people to describe their goals verbally. In Study 1, actors claimed their goals were equally about helping the self and others (viz., moral); agents claimed their goals were primarily about helping the self (viz., selfish). This disparity was evident in both individualist and collectivist cultures, attesting to the universality of the selfish agent. Study 2 compared actors' and agents' motives to those of people role-playing highly prosocial or selfish exemplars. In content (Study 2a) and in the impressions they made on an outside observer (Study 2b), actors' motives were similar to those of the prosocial role-players, whereas agents' motives were similar to those of the selfish role-players. Study 3 accounted for the difference between the actor and agent: Participants claimed that their agent's motives were the more realistic and that their actor's motives were the more idealistic. The selfish agent/moral actor duality may account for why implicit and explicit measures of the same construct diverge, and why feeling watched brings out the better angels of human nature.

  8. CERN Accelerator School: Registration open for Advanced Accelerator Physics course

    CERN Multimedia

    2015-01-01

    Registration is now open for the CERN Accelerator School’s Advanced Accelerator Physics course to be held in Warsaw, Poland from 27 September to 9 October 2015.   The course will be of interest to physicists and engineers who wish to extend their knowledge of accelerator physics. The programme offers core lectures on accelerator physics in the mornings and a practical course with hands-on tuition in the afternoons.  Further information can be found at: http://cas.web.cern.ch/cas/Poland2015/Warsaw-advert.html http://indico.cern.ch/event/361988/

  9. CERN Accelerator School: Registration open for Advanced Accelerator Physics course

    CERN Multimedia

    2015-01-01

    Registration is now open for the CERN Accelerator School’s Advanced Accelerator Physics course to be held in Warsaw, Poland from 27 September to 9 October 2015.   The course will be of interest to physicists and engineers who wish to extend their knowledge of Accelerator Physics. The programme offers core lectures on accelerator physics in the mornings and a practical course with hands-on tuition in the afternoons.  Further information can be found at: http://cas.web.cern.ch/cas/Poland2015/Warsaw-advert.html http://indico.cern.ch/event/361988/

  10. Acceleration Modes and Transitions in Pulsed Plasma Accelerators

    Science.gov (United States)

    Polzin, Kurt A.; Greve, Christine M.

    2018-01-01

    Pulsed plasma accelerators typically operate by storing energy in a capacitor bank and then discharging this energy through a gas, ionizing and accelerating it through the Lorentz body force. Two plasma accelerator types employing this general scheme have typically been studied: the gas-fed pulsed plasma thruster and the quasi-steady magnetoplasmadynamic (MPD) accelerator. The gas-fed pulsed plasma accelerator is generally represented as a completely transient device discharging in approximately 1-10 microseconds. When the capacitor bank is discharged through the gas, a current sheet forms at the breech of the thruster and propagates forward under a j (current density) by B (magnetic field) body force, entraining propellant it encounters. This process is sometimes referred to as detonation-mode acceleration because the current sheet representation approximates that of a strong shock propagating through the gas. Acceleration of the initial current sheet ceases when either the current sheet reaches the end of the device and is ejected or when the current in the circuit reverses, striking a new current sheet at the breech and depriving the initial sheet of additional acceleration. In the quasi-steady MPD accelerator, the pulse is lengthened to approximately 1 millisecond or longer and maintained at an approximately constant level during discharge. The time over which the transient phenomena experienced during startup typically occur is short relative to the overall discharge time, which is now long enough for the plasma to assume a relatively steady-state configuration. The ionized gas flows through a stationary current channel in a manner that is sometimes referred to as the deflagration-mode of operation. The plasma experiences electromagnetic acceleration as it flows through the current channel towards the exit of the device. A device that had a short pulse length but appeared to operate in a plasma acceleration regime different from the gas-fed pulsed plasma

  11. Electrostatic accelerators fundamentals and applications

    CERN Document Server

    2005-01-01

    Electrostatic accelerators are an important and widespread subgroup within the broad spectrum of modern, large particle acceleration devices. They are specifically designed for applications that require high-quality ion beams in terms of energy stability and emittance at comparatively low energies (a few MeV). Their ability to accelerate virtually any kind of ion over a continuously tunable range of energies make them a highly versatile tool for investigations in many research fields including, but not limited to, atomic and nuclear spectroscopy, heavy ion reactions, accelerator mass spectroscopy as well as ion-beam analysis and modification. The book is divided into three parts. The first part concisely introduces the field of accelerator technology and techniques that emphasize their major modern applications. The second part treats the electrostatic accelerator per se: its construction and operational principles as well as its maintenance. The third part covers all relevant applications in which electrosta...

  12. Formalizing Properties of Agents

    Science.gov (United States)

    1993-05-01

    of any possible agent. For example, consider the task of getting a particular star to go supernova at a particular time. The star either will go... supernova or not, independent of what the agent does. 45 We define an independent task to be a task where if one agent succeeds in a given set of initial...Scott Reilly, Lonnie Chrisman. Siegfried Bocionek and David Zabowski for their comments. 48 A Z primer This appendix contains a short introduction to the

  13. Network acceleration techniques

    Science.gov (United States)

    Crowley, Patricia (Inventor); Awrach, James Michael (Inventor); Maccabe, Arthur Barney (Inventor)

    2012-01-01

    Splintered offloading techniques with receive batch processing are described for network acceleration. Such techniques offload specific functionality to a NIC while maintaining the bulk of the protocol processing in the host operating system ("OS"). The resulting protocol implementation allows the application to bypass the protocol processing of the received data. Such can be accomplished this by moving data from the NIC directly to the application through direct memory access ("DMA") and batch processing the receive headers in the host OS when the host OS is interrupted to perform other work. Batch processing receive headers allows the data path to be separated from the control path. Unlike operating system bypass, however, the operating system still fully manages the network resource and has relevant feedback about traffic and flows. Embodiments of the present disclosure can therefore address the challenges of networks with extreme bandwidth delay products (BWDP).

  14. SPS accelerating cavity

    CERN Multimedia

    CERN PhotoLab

    1976-01-01

    The SPS started up with 2 accelerating cavities (each consisting of 5 tank sections) in LSS3. They have a 200 MHz travelling wave structure (see 7411032 and 7802190) and 750 kW of power is fed to each of the cavities from a 1 MW tetrode power amplifier, located in a surface building above, via a coaxial transmission line. Clemens Zettler, builder of the SPS RF system, is standing at the side of one of the cavities. In 1978 and 1979 another 2 cavities were added and entered service in 1980. These were part of the intensity improvement programme and served well for the new role of the SPS as proton-antiproton collider. See also 7411032, 8011289, 8104138, 8302397.

  15. ACCELERATING NANO-TECHNOLOGICAL

    DEFF Research Database (Denmark)

    Jensen, Jens Stissing; Koch, Christian

    2007-01-01

    By viewing the construction industry as a technological innovation system (TIS) this paper discusses possible initiatives to accelerate nanotechnological innovations. The point of departure is a recent report on the application of nano-technology in the Danish construction industry, which concludes...... that opportunities are generally poorly appreciated by the industry and research communities alike. It is found that the construction industry is characterized by low-tech trajectories where dedicated innovation networks are often too fragile for innovations to stabilize and diffuse. The institutional features...... of the system are furthermore poorly equipped at identifying potentials within high-tech areas. In order to exploit the potentials of nano-technology it is thus argued that an alternative TIS needs to be established. Initiatives should identify and support “incubation rooms” or marked niches in order...

  16. GPU Accelerated Prognostics

    Science.gov (United States)

    Gorospe, George E., Jr.; Daigle, Matthew J.; Sankararaman, Shankar; Kulkarni, Chetan S.; Ng, Eley

    2017-01-01

    Prognostic methods enable operators and maintainers to predict the future performance for critical systems. However, these methods can be computationally expensive and may need to be performed each time new information about the system becomes available. In light of these computational requirements, we have investigated the application of graphics processing units (GPUs) as a computational platform for real-time prognostics. Recent advances in GPU technology have reduced cost and increased the computational capability of these highly parallel processing units, making them more attractive for the deployment of prognostic software. We present a survey of model-based prognostic algorithms with considerations for leveraging the parallel architecture of the GPU and a case study of GPU-accelerated battery prognostics with computational performance results.

  17. HIGH ENERGY PARTICLE ACCELERATOR

    Science.gov (United States)

    Courant, E.D.; Livingston, M.S.; Snyder, H.S.

    1959-04-14

    An improved apparatus is presented for focusing charged particles in an accelerator. In essence, the invention includes means for establishing a magnetic field in discrete sectors along the path of moving charged particles, the magnetic field varying in each sector in accordance with the relation. B = B/ sub 0/ STAln (r-r/sub 0/)/r/sub 0/!, where B/sub 0/ is the value of the magnetic field at the equilibrium orbit of radius r/sub 0/ of the path of the particles, B equals the magnetic field at the radius r of the chamber and n equals the magnetic field gradient index, the polarity of n being abruptly reversed a plurality of times as the particles travel along their arcuate path. With this arrangement, the particles are alternately converged towards the axis of their equillbrium orbit and diverged therefrom in successive sectors with a resultant focusing effect.

  18. ISOLDE - Accelerating Future

    CERN Multimedia

    CERN. Geneva

    2003-01-01

    Isotope Separation On-Line (ISOL) was first developed in Copenhagen in the late 50s. The technique was taken to CERN in the 60s and the CERN facility was given the name ISOLDE. The method is based on energetic protons hitting a solid target. The reaction products produced through spallation, fission and fragmentation are heated out in the form of an electrically neutral gas. In the subsequent steps the gas is ionized, accelerated and magnetically separated to produce isotopically pure beams for experiments in nuclear physics, atomic physics, astrophysics, solid state physics and for medical applications. An overview will be given of the physics at ISOLDE as well as over the techniques used to produce the necessary isotopes. Furthermore, a part of the talk will be dedicated to the future plans at ISOLDE including the proposal to build a next generation radioactive beam facility at CERN. The talk ends with a guided visit to the ISOLDE facility. Prerequisite knowledge: None.

  19. Accelerator based fusion reactor

    Science.gov (United States)

    Liu, Keh-Fei; Chao, Alexander Wu

    2017-08-01

    A feasibility study of fusion reactors based on accelerators is carried out. We consider a novel scheme where a beam from the accelerator hits the target plasma on the resonance of the fusion reaction and establish characteristic criteria for a workable reactor. We consider the reactions d+t\\to n+α,d+{{}3}{{H}\\text{e}}\\to p+α , and p+{{}11}B\\to 3α in this study. The critical temperature of the plasma is determined from overcoming the stopping power of the beam with the fusion energy gain. The needed plasma lifetime is determined from the width of the resonance, the beam velocity and the plasma density. We estimate the critical beam flux by balancing the energy of fusion production against the plasma thermo-energy and the loss due to stopping power for the case of an inert plasma. The product of critical flux and plasma lifetime is independent of plasma density and has a weak dependence on temperature. Even though the critical temperatures for these reactions are lower than those for the thermonuclear reactors, the critical flux is in the range of {{10}22}-{{10}24}~\\text{c}{{\\text{m}}-2}~{{\\text{s}}-1} for the plasma density {ρt}={{10}15}~\\text{c}{{\\text{m}}-3} in the case of an inert plasma. Several approaches to control the growth of the two-stream instability are discussed. We have also considered several scenarios for practical implementation which will require further studies. Finally, we consider the case where the injected beam at the resonance energy maintains the plasma temperature and prolongs its lifetime to reach a steady state. The equations for power balance and particle number conservation are given for this case.

  20. Cast dielectric composite linear accelerator

    Science.gov (United States)

    Sanders, David M [Livermore, CA; Sampayan, Stephen [Manteca, CA; Slenes, Kirk [Albuquerque, NM; Stoller, H M [Albuquerque, NM

    2009-11-10

    A linear accelerator having cast dielectric composite layers integrally formed with conductor electrodes in a solventless fabrication process, with the cast dielectric composite preferably having a nanoparticle filler in an organic polymer such as a thermosetting resin. By incorporating this cast dielectric composite the dielectric constant of critical insulating layers of the transmission lines of the accelerator are increased while simultaneously maintaining high dielectric strengths for the accelerator.

  1. Collective accelerator for electron colliders

    Energy Technology Data Exchange (ETDEWEB)

    Briggs, R.J.

    1985-05-13

    A recent concept for collective acceleration and focusing of a high energy electron bunch is discussed, in the context of its possible applicability to large linear colliders in the TeV range. The scheme can be considered to be a member of the general class of two-beam accelerators, where a high current, low voltage beam produces the acceleration fields for a trailing high energy bunch.

  2. NIIEFA accelerators for applied purposes

    Science.gov (United States)

    Vorogushin, M. F.; Strokach, A. P.; Filatov, O. G.

    2016-12-01

    Since the foundation of the institute, we have designed and delivered more than three hundred different accelerators to Russia and abroad: cyclotrons, linear accelerators, and neutron generators. The technical characteristics of our equipment makes it competitive on the international market. Here we present the application, main parameters, and status of accelerators manufactured by NIIEFA, as well as prospects for the development of electrophysical systems for applied purposes.

  3. Motion Representation with Acceleration Images

    OpenAIRE

    Kataoka, Hirokatsu; He, Yun; Shirakabe, Soma; Satoh, Yutaka

    2016-01-01

    Information of time differentiation is extremely important cue for a motion representation. We have applied first-order differential velocity from a positional information, moreover we believe that second-order differential acceleration is also a significant feature in a motion representation. However, an acceleration image based on a typical optical flow includes motion noises. We have not employed the acceleration image because the noises are too strong to catch an effective motion feature ...

  4. Particle Acceleration by MHD Turbulence

    OpenAIRE

    Cho, Jungyeon; Lazarian, A.

    2005-01-01

    Recent advances in understanding of magnetohydrodynamic (MHD) turbulence call for revisions in the picture of particle acceleration. We make use of the recently established scaling of slow and fast MHD modes in strong and weak MHD turbulence to provide a systematic study of particle acceleration in magnetic pressure (low-$\\beta$) and gaseous pressure (high-$\\beta$) dominated plasmas. We consider the acceleration by large scale compressions in both slow and fast particle diffusion limits. We c...

  5. Representation in dynamical agents.

    Science.gov (United States)

    Ward, Ronnie; Ward, Robert

    2009-04-01

    This paper extends experiments by Beer [Beer, R. D. (1996). Toward the evolution of dynamical neural networks for minimally cognitive behavior. In P. Maes, M. Mataric, J. Meyer, J. Pollack, & S. Wilson (Eds.), From animals to animats 4: Proceedings of the fourth international conference on simulation of adaptive behavior (pp. 421-429). MIT Press; Beer, R. D. (2003). The dynamics of active categorical perception in an evolved model agent (with commentary and response). Adaptive Behavior, 11 (4), 209-243] with an evolved, dynamical agent to further explore the question of representation in cognitive systems. Beer's environmentally-situated visual agent was controlled by a continuous-time recurrent neural network, and evolved to perform a categorical perception task, discriminating circles from diamonds. Despite the agent's high levels of discrimination performance, Beer found no evidence of internal representation in the best-evolved agent's nervous system. Here we examine the generality of this result. We evolved an agent for shape discrimination, and performed extensive behavioral analyses to test for representation. In this case we find that agents developed to discriminate equal-width shapes exhibit what Clark [Clark, A. (1997). The dynamical challenge. Cognitive Science, 21 (4), 461-481] calls "weak-substantive representation". The agent had internal configurations that (1) were understandably related to the object in the environment, and (2) were functionally used in a task relevant way when the target was not visible to the agent.

  6. Decontamination Data - Blister Agents

    Data.gov (United States)

    U.S. Environmental Protection Agency — Decontamination efficacy data for blister agents on various building materials using various decontamination solutions. This dataset is associated with the following...

  7. Accelerators for research and applications

    Energy Technology Data Exchange (ETDEWEB)

    Alonso, J.R.

    1990-06-01

    The newest particle accelerators are almost always built for extending the frontiers of research, at the cutting edge of science and technology. Once these machines are operating and these technologies mature, new applications are always found, many of which touch our lives in profound ways. The evolution of accelerator technologies will be discussed, with descriptions of accelerator types and characteristics. The wide range of applications of accelerators will be discussed, in fields such as nuclear science, medicine, astrophysics and space-sciences, power generation, airport security, materials processing and microcircuit fabrication. 13 figs.

  8. Compact accelerator for medical therapy

    Energy Technology Data Exchange (ETDEWEB)

    Caporaso, George J.; Chen, Yu-Jiuan; Hawkins, Steven A.; Sampayan, Stephen E.; Paul, Arthur C.

    2010-05-04

    A compact accelerator system having an integrated particle generator-linear accelerator with a compact, small-scale construction capable of producing an energetic (.about.70-250 MeV) proton beam or other nuclei and transporting the beam direction to a medical therapy patient without the need for bending magnets or other hardware often required for remote beam transport. The integrated particle generator-accelerator is actuable as a unitary body on a support structure to enable scanning of a particle beam by direction actuation of the particle generator-accelerator.

  9. Superconducting Radiofrequency (SRF) Acceleration Technology

    Data.gov (United States)

    Federal Laboratory Consortium — SRF cavities enable accelerators to increase particle beam energy levels while minimizing the use of electrical power by all but eliminating electrical resistance....

  10. Short Acceleration Times from Superdiffusive Shock Acceleration in the Heliosphere

    Science.gov (United States)

    Perri, S.; Zimbardo, G.

    2015-12-01

    The analysis of time profiles of particles accelerated at interplanetary shocks allows particle transport properties to be inferred. The frequently observed power-law decay upstream, indeed, implies a superdiffusive particle transport when the level of magnetic field variance does not change as the time interval from the shock front increases. In this context, a superdiffusive shock acceleration (SSA) theory has been developed, allowing us to make predictions of the acceleration times. In this work we estimate for a number of interplanetary shocks, including the solar wind termination shock, the acceleration times for energetic protons in the framework of SSA and we compare the results with the acceleration times predicted by standard diffusive shock acceleration. The acceleration times due to SSA are found to be much shorter than in the classical model, and also shorter than the interplanetary shock lifetimes. This decrease of the acceleration times is due to the scale-free nature of the particle displacements in the framework of superdiffusion. Indeed, very long displacements are possible, increasing the probability for particles far from the front of the shock to return, and short displacements have a high probability of occurrence, increasing the chances for particles close to the front to cross the shock many times.

  11. Teaching Tourism Change Agents

    DEFF Research Database (Denmark)

    Stilling Blichfeldt, Bodil; Kvistgaard, Hans-Peter; Hird, John

    2017-01-01

    course that is part of a Tourism Master’s program, where a major challenge is not only to teach students about change and change agents, but to teach them how change feels and ho w to become change agents. The c hange management course contains an experiment inspired by experiential teaching literature...... change in tourism in the future....

  12. Agents in domestic environments

    NARCIS (Netherlands)

    Glenn Meerstra; Wouter Langerak; Leo van Moergestel; Niels van Nieuwenburg; John-Jules Meyer; Ing. Erik Puik; Franc Pape; Daniël Telgen

    2013-01-01

    Athor supplied : "This paper describes an agent-based architecture for domotics. This architecture is based on requirements about expandability and hardware independence. The heart of the system is a multi-agent system. This system is distributed over several platforms to open the possibility to

  13. Change Agent Survival Guide

    Science.gov (United States)

    Dunbar, Folwell L.

    2011-01-01

    Consulting is a rough racket. Only a tarantula hair above IRS agents, meter maids and used car sales people, the profession is a prickly burr for slings and arrows. Throw in education, focus on dysfunctional schools and call oneself a "change agent," and this bad rap all but disappears. Unfortunately, though, consulting/coaching/mentoring in…

  14. Thomas Edison Accelerated Elementary School.

    Science.gov (United States)

    Levin, Henry M.; Chasin, Gene

    This paper describes early outcomes of a Sacramento, California, elementary school that participated in the Accelerated Schools Project. The school, which serves many minority and poor students, began training for the project in 1992. Accelerated Schools were designed to advance the learning rate of students through a gifted and talented approach,…

  15. COMPASS Accelerator Design Technical Overview

    Energy Technology Data Exchange (ETDEWEB)

    Nanni, Emilio; Dolgashev, Valery; Tantawi, Sami; Neilson, Jeff; /SLAC

    2016-03-14

    This report is a survey of technical options for generating a MeV-class accelerator for space based science applications. The survey was performed focusing on the primary technical requirements of the accelerator in the context of a satellite environment with its unique challenges of limited electrical power (PE), thermal isolation, dimensions, payload requirement and electrical isolation.

  16. Natural Acceleration: Supporting Creative Trajectories

    Science.gov (United States)

    Cohen, LeoNora M.

    2011-01-01

    "Natural acceleration" happens through an internal fire that burns to learn and may transcend school boundaries. Based on their passionate interests and connections with a domain, children who hunger for domain understandings outside school curricula require different types of acceleration, motivated by these interests. The lifeworks,…

  17. Influence of laser radiation on acceleration of postextraction wound healing

    Science.gov (United States)

    Grzesiak-Janas, Grazyna; Kobos, Jozef

    1997-10-01

    The investigations included 50 patients who were subjected to extraction of two adjacent teeth because of chronic periodontal ligament inflammation using 2 percent lignocaine as an anaesthetic agent. One postextraction wound was irradiated with laser light, whereas the second one was left to be healed in a natural way. The use of laser beam accelerates postextraction wound healing on the basis of clinical and cytologic evaluation.

  18. Industrial accelerators and their applications

    CERN Document Server

    Hamm, Marianne E

    2012-01-01

    This unique new book is a comprehensive review of the many current industrial applications of particle accelerators, written by experts in each of these fields. Readers will gain a broad understanding of the principles of these applications, the extent to which they are employed, and the accelerator technology utilized. The book also serves as a thorough introduction to these fields for non-experts and laymen. Due to the increased interest in industrial applications, there is a growing interest among accelerator physicists and many other scientists worldwide in understanding how accelerators are used in various applications. The government agencies that fund scientific research with accelerators are also seeking more information on the many commercial applications that have been or can be developed with the technology developments they are funding. Many industries are also doing more research on how they can improve their products or processes using particle beams.

  19. Accelerators for high intensity beams

    CERN Document Server

    Chou, Weiren

    2014-01-01

    As particle accelerators strive forever increasing performance, high intensity particle beams become one of the critical demands requested across the board by a majority of accelerator users (proton, electron and ion) and for most applications. Much effort has been made by our community to pursue high intensity accelerator performance on a number of fronts. Recognizing its importance, we devote this volume to Accelerators for High Intensity Beams. High intensity accelerators have become a frontier and a network for innovation. They are responsible for many scientific discoveries and technological breakthroughs that have changed our way of life, often taken for granted. A wide range of topics is covered in the fourteen articles in this volume.

  20. Energy Innovation Acceleration Program

    Energy Technology Data Exchange (ETDEWEB)

    Wolfson, Johanna [Fraunhofer USA Inc., Center for Sustainable Energy Systems, Boston, MA (United States)

    2015-06-15

    The Energy Innovation Acceleration Program (IAP) – also called U-Launch – has had a significant impact on early stage clean energy companies in the Northeast and on the clean energy economy in the Northeast, not only during program execution (2010-2014), but continuing into the future. Key results include: Leverage ratio of 105:1; $105M in follow-on funding (upon $1M investment by EERE); At least 19 commercial products launched; At least 17 new industry partnerships formed; At least $6.5M in revenue generated; >140 jobs created; 60% of assisted companies received follow-on funding within 1 year of program completion; In addition to the direct measurable program results summarized above, two primary lessons emerged from our work executing Energy IAP:; Validation and demonstration awards have an outsized, ‘tipping-point’ effect for startups looking to secure investments and strategic partnerships. An ecosystem approach is valuable, but an approach that evaluates the needs of individual companies and then draws from diverse ecosystem resources to fill them, is most valuable of all.

  1. SPS RF Accelerating Cavity

    CERN Multimedia

    1979-01-01

    This picture shows one of the 2 new cavities installed in 1978-1979. The main RF-system of the SPS comprises four cavities: two of 20 m length and two of 16.5 m length. They are all installed in one long straight section (LSS 3). These cavities are of the travelling-wave type operating at a centre frequency of 200.2 MHz. They are wideband, filling time about 700 ns and untuned. The power amplifiers, using tetrodes are installed in a surface building 200 m from the cavities. Initially only two cavities were installed, a third cavity was installed in 1978 and a forth one in 1979. The number of power amplifiers was also increased: to the first 2 MW plant a second 2 MW plant was added and by end 1979 there were 8 500 kW units combined in pairs to feed each of the 4 cavities with up to about 1 MW RF power, resulting in a total accelerating voltage of about 8 MV. See also 7412016X, 7412017X, 7411048X

  2. LHC Dipoles Accelerate

    CERN Multimedia

    2001-01-01

    Andrezej Siemko (left), Peter Sievers (centre), and Lucio Rossi (right), have the exciting challenge of preparing and testing 2000 magnets for the LHC. The LHC is going to require a lot of powerful magnets by the time it begins operation in 2006. More specifically, it is going to need 130 special magnets, 400 quadrupoles, and a whopping 1250 dipoles! Preparing and testing these magnets for the conditions they will encounter in the LHC is not an easy task. But evaluation of the most recently received magnet, from the German company Noell, is showing that while the monumental task of receiving and testing nearly 2000 magnets is going to be exhausting, the goals are definitely attainable. At the moment and over the next year, pre-series magnets (the magnets that CERN uses to fine tune performance) are arriving slowly (90 in total will arrive), but by 2003 the rate of series magnet arrival will accelerate to 9 per week, that's over 450 in a single year! And working with these magnets when they arrive is tough. ...

  3. The entangled accelerating universe

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez-Diaz, Pedro F. [Colina de los Chopos, Instituto de Fisica Fundamental, Consejo Superior de Investigaciones Cientificas, Serrano 121, 28006 Madrid (Spain); Estacion Ecologica de Biocosmologia, Pedro de Alvarado, 14, 06411-Medellin (Spain)], E-mail: p.gonzalezdiaz@imaff.cfmac.csic.es; Robles-Perez, Salvador [Colina de los Chopos, Instituto de Fisica Fundamental, Consejo Superior de Investigaciones Cientificas, Serrano 121, 28006 Madrid (Spain); Estacion Ecologica de Biocosmologia, Pedro de Alvarado, 14, 06411-Medellin (Spain)

    2009-08-31

    Using the known result that the nucleation of baby universes in correlated pairs is equivalent to spacetime squeezing, we show in this Letter that there exists a T-duality symmetry between two-dimensional warp drives, which are physically expressible as localized de Sitter little universes, and two-dimensional Tolman-Hawking and Gidding-Strominger baby universes respectively correlated in pairs, so that the creation of warp drives is also equivalent to spacetime squeezing. Perhaps more importantly, it has been also seen that the nucleation of warp drives entails a violation of the Bell's inequalities, and hence the phenomena of quantum entanglement, complementarity and wave function collapse. These results are generalized to the case of any dynamically accelerating universe filled with dark or phantom energy whose creation is also physically equivalent to spacetime squeezing and to the violation of the Bell's inequalities, so that the universe we are living in should be governed by essential sharp quantum theory laws and must be a quantum entangled system.

  4. Cosmic transparency and acceleration

    Science.gov (United States)

    Holanda, R. F. L.; Pereira, S. H.; Jain, Deepak

    2018-01-01

    In this paper, by considering an absorption probability independent of photon wavelength, we show that current type Ia supernovae (SNe Ia) and gamma-ray burst (GRB) observations plus high-redshift measurements of the cosmic microwave background (CMB) radiation temperature support cosmic acceleration regardless of the transparent-universe assumption. Two flat scenarios are considered in our analyses: the Λ CDM model and a kinematic model. We consider τ (z )=2 ln (1 +z )ɛ, where τ (z ) denotes the opacity between an observer at z =0 and a source at z . This choice is equivalent to deforming the cosmic distance duality relation as DLDA-1=(1 +z )2+ɛ and, if the absorption probability is independent of photon wavelength, the CMB temperature evolution law is TCMB(z )=T0(1 +z )1+2 ɛ /3. By marginalizing on the ɛ parameter, our analyses rule out a decelerating universe at 99.99% C.L. for all scenarios considered. Interestingly, by considering only SNe Ia and GRBs observations, we obtain that a decelerated universe—indicated by ΩΛ≤0.33 and q0>0 —is ruled out around 1.5 σ C.L. and 2 σ C.L., respectively, regardless of the transparent-universe assumption.

  5. Hot Spot Cosmic Accelerators

    Science.gov (United States)

    2002-11-01

    length of more than 3 million light-years, or no less than one-and-a-half times the distance from the Milky Way to the Andromeda galaxy, this structure is indeed gigantic. The region where the jets collide with the intergalactic medium are known as " hot spots ". Superposing the intensity contours of the radio emission from the southern "hot spot" on a near-infrared J-band (wavelength 1.25 µm) VLT ISAAC image ("b") shows three distinct emitting areas; they are even better visible on the I-band (0.9 µm) FORS1 image ("c"). This emission is obviously associated with the shock front visible on the radio image. This is one of the first times it has been possible to obtain an optical/near-IR image of synchrotron emission from such an intergalactic shock and, thanks to the sensitivity and image sharpness of the VLT, the most detailed view of its kind so far . The central area (with the strongest emission) is where the plasma jet from the galaxy centre hits the intergalactic medium. The light from the two other "knots", some 10 - 15,000 light-years away from the central "hot spot", is also interpreted as synchrotron emission. However, in view of the large distance, the astronomers are convinced that it must be caused by electrons accelerated in secondary processes at those sites . The new images thus confirm that electrons are being continuously accelerated in these "knots" - hence called "cosmic accelerators" - far from the galaxy and the main jets, and in nearly empty space. The exact physical circumstances of this effect are not well known and will be the subject of further investigations. The present VLT-images of the "hot spots" near 3C 445 may not have the same public appeal as some of those beautiful images that have been produced by the same instruments during the past years. But they are not less valuable - their unusual importance is of a different kind, as they now herald the advent of fundamentally new insights into the mysteries of this class of remote and active

  6. EXHIBITION: Accelerated Particles

    CERN Multimedia

    2004-01-01

    http://www.cern.ch/cern50/ An exhibition of plastic arts and two evenings of performances by sound and visual artists as part of CERN's fiftieth anniversary celebrations. The fiftieth anniversary of a world famous organization like CERN, an international laboratory specializing in fundamental research, is a cause for celebration. Since March this year, Geneva and neighbouring parts of France have been the venues for a wealth of small and large-scale events, which will continue until November. Given CERN's location in the commune of Meyrin, the ForuMeyrin is hosting two "salons" consisting of an exhibition of plastic arts and evenings of music and visual arts performances with the collective title of "Accelerated Particles". Several works will be exhibited and performed. Salon des matières: An exhibition of plastic arts Until Wednesday 3 November 2004. Tuesdays to Fridays: 4.00 p.m. to 7.00 p.m. Saturdays: 2.00 p.m. to 6.00 p.m. Doors open late on the evening of the performances. Salon des ...

  7. EXHIBITION: Accelerated Particles

    CERN Multimedia

    2004-01-01

    An exhibition of plastic arts and two evenings of performances by sound and visual artists as part of CERN's 50th anniversary celebrations. Fifty candles for CERN, an international laboratory renowned for fundamental research, is a cause for celebration. Since March this year, Geneva and neighbouring parts of France have been the venues for a wealth of small and large-scale events, which will continue until November. Given CERN's location in the commune of Meyrin, the ForuMeyrin is hosting exhibitions of plastic arts and performances entitled: Accelerated Particles. Several works will be exhibited and performed in two 'salons'. Salon des matières: An exhibition of plastic arts From Tues 12 October to Wed 3 November 2004 Tuesdays to Fridays: 16:00 to 19:00 Saturdays: 14:00 to 18:00 Exhibition open late on performance nights, entrance free Salon des particules: Musical and visual performances Tues 12 and Mon 25 October from 20:00 to 23:00 Preview evening for both events: Tues 12 October from 18:...

  8. CAS CERN Accelerator School 5th General Accelerator Physics Course

    Science.gov (United States)

    Turner, S.

    1994-01-01

    The fifth CERN Accelerator School (CAS) basic course on General Accelerator Physics was given at the University of Jyvaeskylae, Finland, from 7 to 18 September 1992. Its syllabus was based on the previous similar courses held at Gif-sur-Yvette in 1984, Aarhus 1986, Salamanca 1988 and Juelich 1990, and whose proceedings were published as CERN Reports 85-19, 87-10, 89-05 and 91-04, respectively. However, certain topics were treated in a different way, improved or extended, while new subjects were introduced. As far as the proceedings of this school are concerned the opportunity was taken not only to include the lectures presented but also to select and revise the most appropriate chapters from the previous similar schools. In this way the present volumes constitute a rather complete introduction to all aspects of the design and construction of particle accelerators, including optics, emittance, luminosity, longitudinal and transverse beam dynamics, insertions, chromaticity, transfer lines, resonances, accelerating structures, tune shifts, coasting beams, lifetime, synchrotron radiation, radiation damping, beam-beam effects, diagnostics, cooling, ion and positron sources, RF and vacuum systems, injection and extraction, conventional, permanent and superconducting magnets, cyclotrons, RF linear accelerators, microtrons, as well as applications of particle accelerators (including therapy) and the history of accelerators. See hints under the relevant topics.

  9. Biological warfare agents

    Directory of Open Access Journals (Sweden)

    Duraipandian Thavaselvam

    2010-01-01

    Full Text Available The recent bioterrorist attacks using anthrax spores have emphasized the need to detect and decontaminate critical facilities in the shortest possible time. There has been a remarkable progress in the detection, protection and decontamination of biological warfare agents as many instrumentation platforms and detection methodologies are developed and commissioned. Even then the threat of biological warfare agents and their use in bioterrorist attacks still remain a leading cause of global concern. Furthermore in the past decade there have been threats due to the emerging new diseases and also the re-emergence of old diseases and development of antimicrobial resistance and spread to new geographical regions. The preparedness against these agents need complete knowledge about the disease, better research and training facilities, diagnostic facilities and improved public health system. This review on the biological warfare agents will provide information on the biological warfare agents, their mode of transmission and spread and also the detection systems available to detect them. In addition the current information on the availability of commercially available and developing technologies against biological warfare agents has also been discussed. The risk that arise due to the use of these agents in warfare or bioterrorism related scenario can be mitigated with the availability of improved detection technologies.

  10. EDITORIAL: Laser and plasma accelerators Laser and plasma accelerators

    Science.gov (United States)

    Bingham, Robert

    2009-02-01

    This special issue on laser and plasma accelerators illustrates the rapid advancement and diverse applications of laser and plasma accelerators. Plasma is an attractive medium for particle acceleration because of the high electric field it can sustain, with studies of acceleration processes remaining one of the most important areas of research in both laboratory and astrophysical plasmas. The rapid advance in laser and accelerator technology has led to the development of terawatt and petawatt laser systems with ultra-high intensities and short sub-picosecond pulses, which are used to generate wakefields in plasma. Recent successes include the demonstration by several groups in 2004 of quasi-monoenergetic electron beams by wakefields in the bubble regime with the GeV energy barrier being reached in 2006, and the energy doubling of the SLAC high-energy electron beam from 42 to 85 GeV. The electron beams generated by the laser plasma driven wakefields have good spatial quality with energies ranging from MeV to GeV. A unique feature is that they are ultra-short bunches with simulations showing that they can be as short as a few femtoseconds with low-energy spread, making these beams ideal for a variety of applications ranging from novel high-brightness radiation sources for medicine, material science and ultrafast time-resolved radiobiology or chemistry. Laser driven ion acceleration experiments have also made significant advances over the last few years with applications in laser fusion, nuclear physics and medicine. Attention is focused on the possibility of producing quasi-mono-energetic ions with energies ranging from hundreds of MeV to GeV per nucleon. New acceleration mechanisms are being studied, including ion acceleration from ultra-thin foils and direct laser acceleration. The application of wakefields or beat waves in other areas of science such as astrophysics and particle physics is beginning to take off, such as the study of cosmic accelerators considered

  11. Agent-Based Optimization

    CERN Document Server

    Jędrzejowicz, Piotr; Kacprzyk, Janusz

    2013-01-01

    This volume presents a collection of original research works by leading specialists focusing on novel and promising approaches in which the multi-agent system paradigm is used to support, enhance or replace traditional approaches to solving difficult optimization problems. The editors have invited several well-known specialists to present their solutions, tools, and models falling under the common denominator of the agent-based optimization. The book consists of eight chapters covering examples of application of the multi-agent paradigm and respective customized tools to solve  difficult optimization problems arising in different areas such as machine learning, scheduling, transportation and, more generally, distributed and cooperative problem solving.

  12. "small ACCELERATORS" 24 May - 2 June 2005

    CERN Multimedia

    2005-01-01

    CERN Accelerator School and Kernfysisch Versneller Instituut (KVI) Groningen, the Netherlands announce a course on "Small Accelerators", Hotel Golden Tulip Drenthe, Zeegse, the Netherlands, 24 May - 2 June 2005. This specialised course is dedicated to the physics and the main applications of small accelerators. The course will review the different accelerator types as well as their specificities in terms of accelerator physics.

  13. Particle acceleration in binaries

    Directory of Open Access Journals (Sweden)

    Sinitsyna V.G.

    2017-01-01

    Full Text Available Cygnus X-3 massive binary system is one of the powerful sources of radio and X-ray emission consisting of an accreting compact object, probably a black hole, with a Wolf-Rayet star companion. Based on the detections of ultra high energy gamma-rays by Kiel and Havera Park, Cygnus X-3 has been proposed to be one of the most powerful sources of charged cosmic ray particles in the Galaxy. The results of long-term observations of the Cyg X-3 binary at energies 800 GeV–85 TeV detected by SHALON in 1995 are presented with images, integral spectra and spectral energy distribution. The identification of source with Cygnus X-3 detected by SHALON was secured by the detection of its 4.8 hour orbital period in TeV gamma-rays. During the whole observation period of Cyg X-3 with SHALON significant flux increases were detected at energies above 0.8 TeV. These TeV flux increases are correlated with flaring activity at a lower energy range of X-ray and/or at observations of Fermi LAT as well as with radio emission from the relativistic jets of Cygnus X-3. The variability of very high-energy gamma-radiation and correlation of radiation activity in the wide energy range can provide essential information on particle mechanism production up to very high energies. Whereas, modulation of very high energy emission connected to the orbital motion of the binary system, provides an understanding of the emission processes, nature and location of particle acceleration.

  14. Particle acceleration in binaries

    Science.gov (United States)

    Sinitsyna, V. G.; Sinitsyna, V. Y.

    2017-06-01

    Cygnus X-3 massive binary system is one of the powerful sources of radio and X-ray emission consisting of an accreting compact object, probably a black hole, with a Wolf-Rayet star companion. Based on the detections of ultra high energy gamma-rays by Kiel and Havera Park, Cygnus X-3 has been proposed to be one of the most powerful sources of charged cosmic ray particles in the Galaxy. The results of long-term observations of the Cyg X-3 binary at energies 800 GeV-85 TeV detected by SHALON in 1995 are presented with images, integral spectra and spectral energy distribution. The identification of source with Cygnus X-3 detected by SHALON was secured by the detection of its 4.8 hour orbital period in TeV gamma-rays. During the whole observation period of Cyg X-3 with SHALON significant flux increases were detected at energies above 0.8 TeV. These TeV flux increases are correlated with flaring activity at a lower energy range of X-ray and/or at observations of Fermi LAT as well as with radio emission from the relativistic jets of Cygnus X-3. The variability of very high-energy gamma-radiation and correlation of radiation activity in the wide energy range can provide essential information on particle mechanism production up to very high energies. Whereas, modulation of very high energy emission connected to the orbital motion of the binary system, provides an understanding of the emission processes, nature and location of particle acceleration.

  15. Acceleration of particles in plasmas

    CERN Multimedia

    CERN. Geneva

    2007-01-01

    The accelerating fields in radio-frequency accelerators are limited to roughly 100 MV/m due to material breakdown which occurs on the walls of the structure. In contrast, a plasma, being already ionized, can support electric fields in excess of 100 GV/m. Such high accelerating gradients hold the promise of compact particle accelerators. Plasma acceleration has been an emerging and fast growing field of research in the past two decades. In this series of lectures, we will review the principles of plasma acceleration. We will see how relativistic plasma waves can be excited using an ultra-intense laser or using a particle beam. We will see how these plasma waves can be used to accelerate electrons to high energy in short distances. Throughout the lectures, we will also review recent experimental results. Current laser-plasma experiments throughout the world have shown that monoenergetic electron beams from 100 MeV to 1 GeV can be obtained in distances ranging from the millimetre to the centimetre. Experiments a...

  16. Application of electron accelerator worldwide

    Energy Technology Data Exchange (ETDEWEB)

    Machi, Sueo [Japan Atomic Industrial Forum, Inc., Tokyo (Japan)

    2003-02-01

    Electron accelerator is an important radiation source for radiation technology, which covers broad fields such as industry, health care, food and environmental protection. There are about 1,000 electron accelerators for radiation processing worldwide. Electron accelerator has advantage over Co-60 irradiator in term of high dose rate and power, assurance of safety, and higher economic performance at larger volume of irradiation. Accelerator generating higher energy in the range of 10 MeV and high power electron beam is now commercially available. There is a trend to use high-energy electron accelerator replacing Co-60 in case of large through-put of medical products. Irradiated foods, in particular species, are on the commercial market in 35 countries. Electron accelerator is used efficiently and economically for production of new or modified polymeric materials through radiation-induced cross-linking, grafting and polymerization reaction. Another important application of electron beam is the curing of surface coatings in the manufacture of products. Electron accelerators of large capacity are used for cleaning exhaust gases in industrial scale. Economic feasibility studies of this electron beam process have shown that this technology is more cost effective than the conventional process. It should be noted that the conventional limestone process produce gypsum as a by-product, which cannot be used in some countries. By contrast, the by-product of the electron beam process is a valuable fertilizer. (Y. Tanaka)

  17. 2014 CERN Accelerator Schools: Beam Loss and Accelerator Protection

    CERN Multimedia

    2014-01-01

    The US-CERN-JAPAN-RUSSIA Joint International Accelerator School is organising a course on Beam Loss and Accelerator Protection to be held in Newport Beach, California, USA from 5-14 November, 2014.    This school is intended for physicists and engineers who are or may be engaged in the design, construction, and/or operation of accelerators with high power photon or particle beams and/or accelerator sub-systems with large stored energy. Application deadlines are 15 August and 4 September. Further information on this Joint School can be found at: http://cas.web.cern.ch/cas/JAS/Newport%20Beach%202014/NPBadvert.html http://indico.cern.ch/event/287647/ http://uspas.fnal.gov/programs/JAS/JAS14.shtml

  18. Delta agent (Hepatitis D)

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/000216.htm Hepatitis D (Delta agent) To use the sharing features on this page, please enable JavaScript. Hepatitis D is a viral infection caused by the ...

  19. Agent Standards Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The innovation of the work herein proposed is the development of standards for software autonomous agents. These standards are essential to achieve software...

  20. Superconducting Magnets for Particle Accelerators

    CERN Document Server

    Bottura, Luca; Yamamoto, Akira; Zlobin, Alexander V

    2016-01-01

    In this paper we summarize the evolution and contributions of superconducting magnets to particle accelerators as chronicled over the last 50 years of Particle Accelerator Conferences (PAC, NA-PAC and IPAC). We begin with an historical overview based primarily on PAC Proceedings augmented with references to key milestones in the development of superconducting magnets for particle accelerators. We then provide some illustrative examples of applications that have occurred over the past 50 years, focusing on those that have either been realized in practice or provided technical development for other projects, with discussion of possible future applications.

  1. Diffraction Accelerator Of Charged Particles

    CERN Document Server

    Alekseev, Yu K; Kosarev, A A; Poseryaev, A V; Shvedunov, V I; Vetrov, A A; Zayarniy, D A

    2004-01-01

    We present the results of theoretical and numerical analysis of the physical processes for laser linear accelerator based on two symmetric resonance diffraction gratings with double-sided accelerating field excitation. Structures parameters optimization provides π-mode field amplitude distribution in neighboring diffraction zone. The maximum energy gradient restricted by ablation processes in grating materials is estimated as 1-3 GeV/m. The numerical analyses and analytical approximation of electric and magnetic field structures are done, longitudinal and transverse electron beam dynamics in accelerating systems are considered, wake fields and focusing properties of diffraction gratings are estimated.

  2. Developing effective change agents.

    Science.gov (United States)

    Daniels, L A

    1986-01-01

    With small/rural hospitals employing a multitude of professionals it becomes imperative that trainers explore ways to develop "self-help" or "change agent" groups if training departments are to persist ... indeed exist. The approach described here concentrates not only on developing the training director's skills but also on developing the skills of department managers and supervisors in facilitating change and becoming change agents. It also illustrates the importance of cooperation between department heads and the education and training staff.

  3. Agent amplified communication

    Energy Technology Data Exchange (ETDEWEB)

    Kautz, H.; Selman, B.; Milewski, A. [AT& T Laboratories, Murray Hill, NJ (United States)

    1996-12-31

    We propose an agent-based framework for assisting and simplifying person-to-person communication for information gathering tasks. As an example, we focus on locating experts for any specified topic. In our approach, the informal person-to-person networks that exist within an organization are used to {open_quotes}referral chain{close_quotes} requests for expertise. User-agents help automate this process. The agents generate referrals by analyzing records of e-mail communication patterns. Simulation results show that the higher responsiveness of an agent-based system can be effectively traded for the higher accuracy of a completely manual approach. Furthermore, preliminary experience with a group of users on a prototype system has shown that useful automatic referrals can be found in practice. Our experience with actual users has also shown that privacy concerns are central to the successful deployment of personal agents: an advanced agent-based system will therefore need to reason about issues involving trust and authority.

  4. SNEAP 80: symposium of Northeastern Accelerator personnel

    Energy Technology Data Exchange (ETDEWEB)

    Billen, J.H. (ed.)

    1980-01-01

    Reports of operations are presented for twenty-seven facilities, along with reports on accelerators in progress, ion sources, insulating gases, charging systems, stripping foils, accelerating tubes, and upgraded accelerator systems. (GHT)

  5. High temperature superconductor accelerator magnets

    NARCIS (Netherlands)

    van Nugteren, J.

    2016-01-01

    For future particle accelerators bending dipoles are considered with magnetic fields exceeding 20T. This can only be achieved using high temperature superconductors (HTS). These exhibit different properties from classical low temperature superconductors and still require significant research and

  6. Advanced Superconducting Test Accelerator (ASTA)

    Data.gov (United States)

    Federal Laboratory Consortium — The Advanced Superconducting Test Accelerator (ASTA) facility will be based on upgrades to the existing NML pulsed SRF facility. ASTA is envisioned to contain 3 to 6...

  7. Extinction Events Can Accelerate Evolution

    DEFF Research Database (Denmark)

    Lehman, Joel; Miikkulainen, Risto

    2015-01-01

    Extinction events impact the trajectory of biological evolution significantly. They are often viewed as upheavals to the evolutionary process. In contrast, this paper supports the hypothesis that although they are unpredictably destructive, extinction events may in the long term accelerate...

  8. Particle accelerator; the Universe machine

    CERN Multimedia

    Yurkewicz, Katie

    2008-01-01

    "In summer 2008, scientists will switch on one of the largest machines in the world to search for the smallest of particle. CERN's Large Hadron Collider particle accelerator has the potential to chagne our understanding of the Universe."

  9. Sequentially pulsed traveling wave accelerator

    Science.gov (United States)

    Caporaso, George J [Livermore, CA; Nelson, Scott D [Patterson, CA; Poole, Brian R [Tracy, CA

    2009-08-18

    A sequentially pulsed traveling wave compact accelerator having two or more pulse forming lines each with a switch for producing a short acceleration pulse along a short length of a beam tube, and a trigger mechanism for sequentially triggering the switches so that a traveling axial electric field is produced along the beam tube in synchronism with an axially traversing pulsed beam of charged particles to serially impart energy to the particle beam.

  10. Hamiltonian mechanics of stochastic acceleration.

    Science.gov (United States)

    Burby, J W; Zhmoginov, A I; Qin, H

    2013-11-08

    We show how to find the physical Langevin equation describing the trajectories of particles undergoing collisionless stochastic acceleration. These stochastic differential equations retain not only one-, but two-particle statistics, and inherit the Hamiltonian nature of the underlying microscopic equations. This opens the door to using stochastic variational integrators to perform simulations of stochastic interactions such as Fermi acceleration. We illustrate the theory by applying it to two example problems.

  11. Design acceleration in chemical engineering

    OpenAIRE

    Cortes Robles, Guillermo; Negny, Stéphane; Le Lann, Jean-Marc

    2008-01-01

    Nowadays, Chemical Engineering has to face a new industrial context with for example: the gradually falling of hydrocarbon reserves after 2020-2030, relocation, emerging of new domains of application (nano-micro technologies) which necessitate new solutions and knowledges… All this tendencies and demands accelerate the need of tool for design and innovation (technically, technologically). In this context, this paper presents a tool to accelerate innovative preliminary design. This model is ba...

  12. High temperature superconductor accelerator magnets

    OpenAIRE

    van Nugteren, J.

    2016-01-01

    For future particle accelerators bending dipoles are considered with magnetic fields exceeding 20T. This can only be achieved using high temperature superconductors (HTS). These exhibit different properties from classical low temperature superconductors and still require significant research and development before they can be applied in a practical accelerator magnet. In order to study HTS in detail, a five tesla demonstrator magnet named Feather-M2 is designed and constructed. The magnet is ...

  13. High Temperature Superconductor Accelerator Magnets

    OpenAIRE

    Van Nugteren, Jeroen; ten Kate, Herman; de Rijk, Gijs; Dhalle, Marc

    2016-01-01

    For future particle accelerators bending dipoles are considered with magnetic fields exceeding $20T$. This can only be achieved using high temperature superconductors (HTS). These exhibit different properties from classical low temperature superconductors and still require significant research and development before they can be applied in a practical accelerator magnet. In order to study HTS in detail, a five tesla demonstrator magnet named Feather-M2 is designed and constructed. The magnet ...

  14. High-Intensity Proton Accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Jay L. Hirshfield

    2011-12-27

    Analysis is presented for an eight-cavity proton cyclotron accelerator that could have advantages as compared with other accelerators because of its potentially high acceleration gradient. The high gradient is possible since protons orbit in a sequence of TE111 rotating mode cavities of equally diminishing frequencies with path lengths during acceleration that greatly exceed the cavity lengths. As the cavities operate at sequential harmonics of a basic repetition frequency, phase synchronism can be maintained over a relatively wide injection phase window without undue beam emittance growth. It is shown that use of radial vanes can allow cavity designs with significantly smaller radii, as compared with simple cylindrical cavities. Preliminary beam transport studies show that acceptable extraction and focusing of a proton beam after cyclic motion in this accelerator should be possible. Progress is also reported on design and tests of a four-cavity electron counterpart accelerator for experiments to study effects on beam quality arising from variations injection phase window width. This device is powered by four 500-MW pulsed amplifiers at 1500, 1800, 2100, and 2400 MHz that provide phase synchronous outputs, since they are driven from a with harmonics derived from a phase-locked 300 MHz source.

  15. Electrodynamics in accelerated frames revisited

    Energy Technology Data Exchange (ETDEWEB)

    Maluf, J.W. [Instituto de Fisica, Universidade de Brasilia (Brazil); Ulhoa, S.C. [Instituto de Ciencia e Tecnologia, Universidade Federal dos Vales do Jequitinhonha e Mucuri, UFVJM, Diamantina, MG (Brazil)

    2010-10-15

    Maxwell's equations are formulated in arbitrary moving frames by means of tetrad fields, which are interpreted as reference frames adapted to observers in space-time. We assume the existence of a general distribution of charges and currents in an inertial frame. Tetrad fields are used to project the electromagnetic fields and sources on accelerated frames. The purpose is to study several configurations of fields and observers that in the literature are understood as paradoxes. For instance, are the two situations, (i) an accelerated charge in an inertial frame, and (ii) a charge at rest in an inertial frame described from the perspective of an accelerated frame, physically equivalent? Is the electromagnetic radiation the same in both frames? Normally in the analysis of these paradoxes the electromagnetic fields are transformed to (uniformly) accelerated frames by means of a coordinate transformation of the Faraday tensor. In the present approach coordinate and frame transformations are disentangled, and the electromagnetic field in the accelerated frame is obtained through a frame (local Lorentz) transformation. Consequently the fields in the inertial and accelerated frames are described in the same coordinate system. This feature allows the investigation of paradoxes such as the one mentioned above. (Abstract Copyright [2010], Wiley Periodicals, Inc.)

  16. Tutorial on Superconducting Accelerator Magnets

    Science.gov (United States)

    Ball, M. J. Penny; Goodzeit, Carl L.

    1997-05-01

    A multimedia CD-ROM tutorial on the physics and engineering concepts of superconducting magnets for particle accelerators is being developed under a U.S. Dept. of Energy SBIR grant. The tutorial, scheduled for distribution this summer, is targeted to undergraduate junior or senior level science students. However, its unified presentation of the broad range of issues involved in the design of superconducting magnets for accelerators and the extensive detail about the construction process (including animations and video clips) will also be of value to staff of research institutes and industrial concerns with an interest in applied superconductivity or magnet development. The source material, which is based on the world-wide R and D programs to develop superconducting accelerator magnets, is organized in five units with the following themes: Introduction to magnets and accelerators; (2) Superconductors for accelerator magnets; (3) Magnetic design methods for accelerator magnets; (4) Electrical, mechanical, and cryogenic considerations for the final magnet package; (5) Performance characteristics and measurement methods. A detailed outline and examples will be shown.

  17. Accelerator and electrodynamics capability review

    Energy Technology Data Exchange (ETDEWEB)

    Jones, Kevin W [Los Alamos National Laboratory

    2010-01-01

    Los Alamos National Laboratory (LANL) uses capability reviews to assess the science, technology and engineering (STE) quality and institutional integration and to advise Laboratory Management on the current and future health of the STE. Capability reviews address the STE integration that LANL uses to meet mission requirements. The Capability Review Committees serve a dual role of providing assessment of the Laboratory's technical contributions and integration towards its missions and providing advice to Laboratory Management. The assessments and advice are documented in reports prepared by the Capability Review Committees that are delivered to the Director and to the Principal Associate Director for Science, Technology and Engineering (PADSTE). Laboratory Management will use this report for STE assessment and planning. LANL has defined fifteen STE capabilities. Electrodynamics and Accelerators is one of the seven STE capabilities that LANL Management (Director, PADSTE, technical Associate Directors) has identified for review in Fiscal Year (FY) 2010. Accelerators and electrodynamics at LANL comprise a blend of large-scale facilities and innovative small-scale research with a growing focus on national security applications. This review is organized into five topical areas: (1) Free Electron Lasers; (2) Linear Accelerator Science and Technology; (3) Advanced Electromagnetics; (4) Next Generation Accelerator Concepts; and (5) National Security Accelerator Applications. The focus is on innovative technology with an emphasis on applications relevant to Laboratory mission. The role of Laboratory Directed Research and Development (LDRD) in support of accelerators/electrodynamics will be discussed. The review provides an opportunity for interaction with early career staff. Program sponsors and customers will provide their input on the value of the accelerator and electrodynamics capability to the Laboratory mission.

  18. Agents unleashed a public domain look at agent technology

    CERN Document Server

    Wayner, Peter

    1995-01-01

    Agents Unleashed: A Public Domain Look at Agent Technology covers details of building a secure agent realm. The book discusses the technology for creating seamlessly integrated networks that allow programs to move from machine to machine without leaving a trail of havoc; as well as the technical details of how an agent will move through the network, prove its identity, and execute its code without endangering the host. The text also describes the organization of the host's work processing an agent; error messages, bad agent expulsion, and errors in XLISP-agents; and the simulators of errors, f

  19. CAS Accelerator Physics (RF for Accelerators) in Denmark

    CERN Multimedia

    Barbara Strasser

    2010-01-01

    The CERN Accelerator School (CAS) and Aarhus University jointly organised a specialised course on RF for Accelerators, at the Ebeltoft Strand Hotel, Denmark from 8 to 17 June 2010.   Caption The challenging programme focused on the introduction of the underlying theory, the study and the performance of the different components involved in RF systems, the RF gymnastics and RF measurements and diagnostics. This academic part was supplemented with three afternoons dedicated to practical hands-on exercises. The school was very successful, with 100 participants representing 25 nationalities. Feedback from the participants was extremely positive, praising the expertise and enthusiasm of the lecturers, as well as the high standard and excellent quality of their lectures. In addition to the academic programme, the participants were able to visit a small industrial exhibition organised by Aarhus University and take part in a one-day excursion consisting of a visit of the accelerators operated ...

  20. The need for agents

    DEFF Research Database (Denmark)

    Abolfazlian, Ali Reza Kian

    1996-01-01

    I denne artikel arbejder vi med begrebet Intelligent Software Agents (ISAs), som autonomous, social, reactive, proactive og subservient computer systemer. Baseret på socialt psykologiske argumenter viser jeg endvidere, hvordan både den menneskelige natur og det teknologiske stadium, som mennesket...... befinder sig i, forårsager behovet for disse ISAs. Der gives eksempler på ISAs, samt de områder, hvor man har særlige behov for disse agenter, og hvordan nogle af disse ISAs allerede er blevet taget i brug for at løse problemerne i disse områder....

  1. Announcements to Attentive Agents

    DEFF Research Database (Denmark)

    Bolander, Thomas; van Ditmarsch, Hans; Herzig, Andreas

    2016-01-01

    In public announcement logic it is assumed that all agents pay attention to the announcement. Weaker observational conditions can be modelled in action model logic. In this work, we propose a version of public announcement logic wherein it is encoded in the states of the epistemic model which...... agents pay attention to the announcement. This logic is called attention-based announcement logic. We give an axiomatization of the logic and prove that complexity of satisfiability is the same as that of public announcement logic, and therefore lower than that of action model logic. An attention...

  2. DARHT II Scaled Accelerator Tests on the ETA II Accelerator*

    Energy Technology Data Exchange (ETDEWEB)

    Weir, J T; Anaya Jr, E M; Caporaso, G J; Chambers, F W; Chen, Y; Falabella, S; Lee, B S; Paul, A C; Raymond, B A; Richardson, R A; Watson, J A; Chan, D; Davis, H A; Day, L A; Scarpetti, R D; Schultze, M E; Hughes, T P

    2005-05-26

    The DARHT II accelerator at LANL is preparing a series of preliminary tests at the reduced voltage of 7.8 MeV. The transport hardware between the end of the accelerator and the final target magnet was shipped to LLNL and installed on ETA II. Using the ETA II beam at 5.2 MeV we completed a set of experiments designed reduce start up time on the DARHT II experiments and run the equipment in a configuration adapted to the reduced energy. Results of the beam transport using a reduced energy beam, including the kicker and kicker pulser system will be presented.

  3. Metabolic acceleration in Mediterranean Perciformes

    Science.gov (United States)

    Lika, Konstadia; Kooijman, Sebastiaan A. L. M.; Papandroulakis, Nikos

    2014-11-01

    Larval stages are considered the most critical of fish development. During a very short period of time (2 to 3 months), larvae undergo major morphoanatomical and functional changes in order to transform into juveniles while remaining functioning (developing, eating, surviving). Depending on species and environmental conditions, patterns in larval development may vary. We study the patterns of larval development for nine fish species of Perciformes reared under aquaculture conditions and compare them in terms of species-specific parameters derived from DEB theory. We extended the standard DEB model to include metabolic acceleration during the larval period, where maximum specific assimilation and energy conductance increase with length between birth and metabolic metamorphosis. Metabolic acceleration has as a consequence that larvae initially grow slower than juveniles and adults. Our results indicate that the species with higher acceleration have lower growth rates at birth and they also suggest that metabolic acceleration is related to spawning season. High metabolic acceleration of demersal species is associated with summer-autumn spawning in the Mediterranean, where temperature is high and food availability is low.

  4. From autistic to social agents

    NARCIS (Netherlands)

    Dignum, F.; Hofstede, G.J.; Prada, R.

    2014-01-01

    The theory, models and architectures of intelligent agents are based loosely on the theory of intentions from Bratman resulting in the so-called BDI agents. Although this func- tions well for single agents it has been long recognized that this approach falls short for multi-agent systems. It lacks

  5. Agent Persuasion Mechanism of Acquaintance

    Science.gov (United States)

    Jinghua, Wu; Wenguang, Lu; Hailiang, Meng

    Agent persuasion can improve negotiation efficiency in dynamic environment based on its initiative and autonomy, and etc., which is being affected much more by acquaintance. Classification of acquaintance on agent persuasion is illustrated, and the agent persuasion model of acquaintance is also illustrated. Then the concept of agent persuasion degree of acquaintance is given. Finally, relative interactive mechanism is elaborated.

  6. Software Agent Techniques in Design

    DEFF Research Database (Denmark)

    Hartvig, Susanne C

    1998-01-01

    This paper briefly presents studies of software agent techniques and outline aspects of these which can be applied in design agents in integrated civil engineering design environments.......This paper briefly presents studies of software agent techniques and outline aspects of these which can be applied in design agents in integrated civil engineering design environments....

  7. Forest Service special agents, assistant special agents in charge, senior special agents, and supervisory special agents report: nationwide study

    Science.gov (United States)

    Deborah J. Chavez; Joanne F. Tynon

    2007-01-01

    This is the fourth in a series of studies to evaluate perceptions of U.S. Department of Agriculture Forest Service law enforcement personnel of the roles, responsibilities, and issues related to their jobs. An e-mail survey was administered to the 89 Forest Service special agents, assistant special agents in charge, senior special agents, and supervisory special agents...

  8. Programming multi-agent systems

    NARCIS (Netherlands)

    Dastani, Mehdi

    2015-01-01

    With the significant advances in the area of autonomous agents and multi-agent systems in the last decade, promising technologies for the development and engineering of multi-agent systems have emerged. The result is a variety of agent-oriented programming languages, development frameworks,

  9. Accelerator Technology Division annual report, FY 1989

    Energy Technology Data Exchange (ETDEWEB)

    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.

  10. Superconducting linear accelerator system for NSC

    Indian Academy of Sciences (India)

    This paper reports the construction of a superconducting linear accelerator as a booster to the 15 UD Pelletron accelerator at Nuclear Science Centre, New Delhi. The LINAC will use superconducting niobium quarter wave resonators as the accelerating element. Construction of the linear accelerator has progressed ...

  11. SECOND BUYING AGENT

    CERN Multimedia

    SPL - SERVICES ACHATS

    2000-01-01

    Last year the buying agent LOGITRADE started operations on the CERN site, processing purchasing requests for well-defined families of products up to a certain value. It was planned from the outset that a second buying agent would be brought in to handle the remaining product families. So, according to that plan, the company CHARLES KENDALL will be commencing operations at CERN on 8 May 2000 in Building 73, 1st floor, offices 31 and 35 (phone and fax numbers to be announced).Each buying agent will have its own specific list of product families and will handle purchasing requests up to 10'000 CHF.Whenever possible they will provide the requested supplies at a price (including the cost of their own services) which must be equivalent to or lower than the price mentioned on the purchasing request, changing the supplier if necessary. If a lower price cannot be obtained, agents will provide the necessary administrative support free of charge.To ensure that all orders are processed in the best possible conditions, us...

  12. Infectious Agents and Cancer

    African Journals Online (AJOL)

    Hepatocellular carcinoma. Cervical cancer, other anogenital ... The expression of the E6 and E7 open reading frames (ORFs) from high .... protein CagA [3 5]. They also elaborate urease, alcohol dehydrogenase and mucolytic factors. All these agents contribute to the development of cancer following H. pylori infection.

  13. Developing Enculturated Agents

    DEFF Research Database (Denmark)

    Rehm, Matthias

    2010-01-01

    on our cultural profiles that provide us with heuristics of behavior and interpretation. Thus, integrating cultural aspects of communicative behaviors in virtual agents and thus enculturating such systems seems to be inevitable. But culture is a multi-defined domain and thus a number of pitfalls arise...

  14. Socially Intelligent Tutor Agents

    NARCIS (Netherlands)

    Heylen, Dirk K.J.; Nijholt, Antinus; op den Akker, Hendrikus J.A.; Vissers, M.; Aylett, R.; Ballin, D.; Rist, T.

    2003-01-01

    Emotions and personality have received quite a lot of attention the last few years in research on embodied conversational agents. Attention is also increasingly being paid to matters of social psychology and interpersonal aspects, for work of our group). Given the nature of an embodied

  15. Biomimetic Emotional Learning Agents

    OpenAIRE

    Kenyon, Samuel H.

    2005-01-01

    This extended abstract proposes a type of AI agent comprised of: an autonomous real-time control system, low-level emotional learning (including a simple knowledge base that links homeostatic/innate drives to sensory perception states), and a novel sliding-priority drive motivation mechanism. Learning occurs in both phylogenetic and ontogenetic training.

  16. 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.

  17. Superconducting Magnets for Particle Accelerators

    CERN Document Server

    Rossi, L

    2012-01-01

    Superconductivity has been the most influential technology in the field of accelerators in the last 30 years. Since the commissioning of the Tevatron, which demonstrated the use and operability of superconductivity on a large scale, superconducting magnets and rf cavities have been at the heart of all new large accelerators. Superconducting magnets have been the invariable choice for large colliders, as well as cyclotrons and large synchrotrons. In spite of the long history of success, superconductivity remains a difficult technology, requires adequate R&D and suitable preparation, and has a relatively high cost. Hence, it is not surprising that the development has also been marked by a few setbacks. This article is a review of the main superconducting accelerator magnet projects; it highlights the main characteristics and main achievements, and gives a perspective on the development of superconducting magnets for the future generation of very high energy colliders.

  18. Niobium LEP 2 accelerating cavities

    CERN Multimedia

    An accelerating cavity from LEP. This could be cut open to show the layer of niobium on the inside. Operating at 4.2 degrees above absolute zero, the niobium is superconducting and carries an accelerating field of 6 million volts per metre with negligible losses. Each cavity has a surface of 6 m2. The niobium layer is only 1.2 microns thick, ten times thinner than a hair. Such a large area had never been coated to such a high accuracy. A speck of dust could ruin the performance of the whole cavity so the work had to be done in an extremely clean environment. These challenging requirements pushed European industry to new achievements. 256 of these cavities were used in an upgrade of the LEP accelerator to double the energy of the particle beams.

  19. A Multibunch Plasma Wakefield Accelerator

    CERN Document Server

    Kallos, Efthymios; Ben-Zvi, Ilan; Katsouleas, Thomas C; Kimura, Wayne D; Kusche, Karl; Muggli, Patric; Pavlishin, Igor; Pogorelsky, Igor; Yakimenko, Vitaly; Zhou, Feng

    2005-01-01

    We investigate a plasma wakefield acceleration scheme where a train of electron microbunches feeds into a high density plasma. When the microbunch train enters such a plasma that has a corresponding plasma wavelength equal to the microbunch separation distance, a strong wakefield is expected to be resonantly driven to an amplitude that is at least one order of magnitude higher than that using an unbunched beam. PIC simulations have been performed using the beamline parameters of the Brookhaven National Laboratory Accelerator Test Facility operating in the configuration of the STELLA inverse free electron laser (IFEL) experiment. A 65 MeV electron beam is modulated by a 10.6 um CO2 laser beam via an IFEL interaction. This produces a train of ~90 microbunches separated by the laser wavelength. In this paper, we present both a simple theoretical treatment and simulation results that demonstrate promising results for the multibunch technique as a plasma-based accelerator.

  20. Symposium on accelerator mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    None

    1981-01-01

    The area of accelerator mass spectrometry has expanded considerably over the past few years and established itself as an independent and interdisciplinary research field. Three years have passed since the first meeting was held at Rochester. A Symposium on Accelerator Mass Spectrometry was held at Argonne on May 11-13, 1981. In attendance were 96 scientists of whom 26 were from outside the United States. The present proceedings document the program and excitement of the field. Papers are arranged according to the original program. A few papers not presented at the meeting have been added to complete the information on the status of accelerator mass spectrometry. Individual papers were prepared separately for the data base.

  1. Accelerator science in medical physics.

    Science.gov (United States)

    Peach, K; Wilson, P; Jones, B

    2011-12-01

    The use of cyclotrons and synchrotrons to accelerate charged particles in hospital settings for the purpose of cancer therapy is increasing. Consequently, there is a growing demand from medical physicists, radiographers, physicians and oncologists for articles that explain the basic physical concepts of these technologies. There are unique advantages and disadvantages to all methods of acceleration. Several promising alternative methods of accelerating particles also have to be considered since they will become increasingly available with time; however, there are still many technical problems with these that require solving. This article serves as an introduction to this complex area of physics, and will be of benefit to those engaged in cancer therapy, or who intend to acquire such technologies in the future.

  2. Harmonic ratcheting for fast acceleration

    Directory of Open Access Journals (Sweden)

    N. Cook

    2014-04-01

    Full Text Available A major challenge in the design of rf cavities for the acceleration of medium-energy charged ions is the need to rapidly sweep the radio frequency over a large range. From low-power medical synchrotrons to high-power accelerator driven subcritical reactor systems, and from fixed focus alternating gradient accelerators to rapid cycling synchrotrons, there is a strong need for more efficient, and faster, acceleration of protons and light ions in the semirelativistic range of hundreds of MeV/u. A conventional way to achieve a large, rapid frequency sweep (perhaps over a range of a factor of 6 is to use custom-designed ferrite-loaded cavities. Ferrite rings enable the precise tuning of the resonant frequency of a cavity, through the control of the incremental permeability that is possible by introducing a pseudoconstant azimuthal magnetic field. However, rapid changes over large permeability ranges incur anomalous behavior such as the “Q-loss” and “f-dot” loss phenomena that limit performance while requiring high bias currents. Notwithstanding the incomplete understanding of these phenomena, they can be ameliorated by introducing a “harmonic ratcheting” acceleration scheme in which two or more rf cavities take turns accelerating the beam—one turns on when the other turns off, at different harmonics—so that the radio frequency can be constrained to remain in a smaller range. Harmonic ratcheting also has straightforward performance advantages, depending on the particular parameter set at hand. In some typical cases it is possible to halve the length of the cavities, or to double the effective gap voltage, or to double the repetition rate. This paper discusses and quantifies the advantages of harmonic ratcheting in general. Simulation results for the particular case of a rapid cycling medical synchrotron ratcheting from harmonic number 9 to 2 show that stability and performance criteria are met even when realistic engineering details

  3. Acceleration parameters for fluid physics with accelerating bodies

    CSIR Research Space (South Africa)

    Gledhill, Irvy MA

    2016-06-01

    Full Text Available accelerating bodies, and reference must be made, above all, to the Mach number for transonic effects. Other parameters from the literature on impulsive start-up in wind tunnels are also shown to be useful in delimiting regimes of flow, such as the Freymuth...

  4. State of accelerator for therapy

    CERN Document Server

    Maruhashi, A

    2002-01-01

    21 facilities carry out particle radiotherapy in the world and 6 facilities will start in the next year. They are shown in the table. 6 facilities of them exist in Japan. Small accelerator for proton therapy is developed. The area of them becomes smaller than 100 m sup 2. 5 makers, form, kinds of accelerator, length of track, beam energy of them are shown. States of particle radiotherapy in 4 facilities in Japan are explained by the kinds of particle, energy, beam intensity, time structure and radiation room. The important problems are reconsideration of building and compact rotating gantry. The problems of radiotherapy are explained. (S.Y.)

  5. OpenMP for Accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Beyer, J C; Stotzer, E J; Hart, A; de Supinski, B R

    2011-03-15

    OpenMP [13] is the dominant programming model for shared-memory parallelism in C, C++ and Fortran due to its easy-to-use directive-based style, portability and broad support by compiler vendors. Similar characteristics are needed for a programming model for devices such as GPUs and DSPs that are gaining popularity to accelerate compute-intensive application regions. This paper presents extensions to OpenMP that provide that programming model. Our results demonstrate that a high-level programming model can provide accelerated performance comparable to hand-coded implementations in CUDA.

  6. Acceleration effects on atomic clocks

    CERN Document Server

    Dahia, F

    2014-01-01

    We consider a free massive particle inside a box which is dragged by Rindler observers. Admitting that the particle obeys the Klein-Gordon equation, we find the frequencies of the stationary states of this system. Transitions between the stationary states are employed to set a standard frequency for a toy atomic clock. Comparing the energy spectrum of the accelerated system with the energy spectrum of an identical system in an inertial frame, we determine the influence of the instantaneous acceleration on the rate of atomic clocks. We argue that our result does not violate the clock hypothesis.

  7. Electron Cloud Effects in Accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Furman, M.A.

    2012-11-30

    Abstract We present a brief summary of various aspects of the electron-cloud effect (ECE) in accelerators. For further details, the reader is encouraged to refer to the proceedings of many prior workshops, either dedicated to EC or with significant EC contents, including the entire ?ECLOUD? series [1?22]. In addition, the proceedings of the various flavors of Particle Accelerator Conferences [23] contain a large number of EC-related publications. The ICFA Beam Dynamics Newsletter series [24] contains one dedicated issue, and several occasional articles, on EC. An extensive reference database is the LHC website on EC [25].

  8. Seismic response of linear accelerators

    CERN Document Server

    Collette, C; Guinchard, M; Hauviller, C

    2010-01-01

    This paper is divided into two parts. The first part presents recent measurements of ground motion in the LHC tunnel at CERN. From these measurements, an update of the ground motion model currently used in accelerator simulations is presented. It contains new features like a model of the lateral motion and the technical noise. In the second part, it is shown how this model can be used to evaluate the seismic response of a linear accelerator in the frequency domain. Then, the approach is validated numerically on a regular lattice, taking the dynamic behavior of the machine alignment stage and the mechanical stabilization of the quadrupoles into account.

  9. Seismic response of linear accelerators

    Directory of Open Access Journals (Sweden)

    C. Collette

    2010-07-01

    Full Text Available This paper is divided into two parts. The first part presents recent measurements of ground motion in the LHC tunnel at CERN. From these measurements, an update of the ground motion model currently used in accelerator simulations is presented. It contains new features like a model of the lateral motion and the technical noise. In the second part, it is shown how this model can be used to evaluate the seismic response of a linear accelerator in the frequency domain. Then, the approach is validated numerically on a regular lattice, taking the dynamic behavior of the machine alignment stage and the mechanical stabilization of the quadrupoles into account.

  10. Calorimetry at industrial electron accelerators

    DEFF Research Database (Denmark)

    Miller, Arne; Kovacs, A.

    1985-01-01

    Calorimetry is a convenient way to measure doses at industrial electron accelerators, where high absorbed doses (1-100 kGy) are delivered at dose rates of 102-105 Gy s-1 or even higher. Water calorimeters have been used for this purpose for several years, but recently other materials such as grap......Calorimetry is a convenient way to measure doses at industrial electron accelerators, where high absorbed doses (1-100 kGy) are delivered at dose rates of 102-105 Gy s-1 or even higher. Water calorimeters have been used for this purpose for several years, but recently other materials...

  11. Thermodynamics of Accelerating Black Holes.

    Science.gov (United States)

    Appels, Michael; Gregory, Ruth; Kubizňák, David

    2016-09-23

    We address a long-standing problem of describing the thermodynamics of an accelerating black hole. We derive a standard first law of black hole thermodynamics, with the usual identification of entropy proportional to the area of the event horizon-even though the event horizon contains a conical singularity. This result not only extends the applicability of black hole thermodynamics to realms previously not anticipated, it also opens a possibility for studying novel properties of an important class of exact radiative solutions of Einstein equations describing accelerated objects. We discuss the thermodynamic volume, stability, and phase structure of these black holes.

  12. Accelerated hypertension: Treatable yet underdiagnosed

    Directory of Open Access Journals (Sweden)

    Pranav Ish

    2017-01-01

    Full Text Available Patients who present in young age with accelerated hypertension (HTN should always be evaluated for secondary causes of hypertension. Renal parenchyma and vascular diseases constitute the majority of the etiology. Other causes include endocrine diseases such as pheochromocytoma, pregnancy-related HTN, and sleep apnea. We report a 23-year-old female who presented with palpitations and headache under treatment for anxiety from a tertiary care hospital. She was found to have accelerated HTN and was thoroughly worked up for etiology and treatment.

  13. Einstein, Nobel Prize, and Accelerators

    CERN Document Server

    Jarlskog, C

    2005-01-01

    We are celebrating the year of physics thanks to Einstein’s monumental contributions a hundred years ago. Indeed, the current field of accelerator physics is also deeply indebted to him. Why did it take more than a decade and a half for him to be "crowned" in Stockholm by the Nobel Prize? Did he get the Prize for the "wrong" thing? Based on original material from the archives of the Swedish Academy of Sciences, I will discuss how Einstein got the Nobel Prize and will give a short summary of his everlasting impact on the field of accelerator physics.

  14. Hamiltonian theory of stochastic acceleration.

    Science.gov (United States)

    Makhnovskii, Yurii A; Pollak, Eli

    2006-04-01

    Stochastic acceleration, defined in terms of a stochastic equation of motion for the acceleration, is derived from a Hamiltonian model. A free particle is coupled bilinearly to a harmonic bath through the particle's momentum and coordinate. Under appropriate conditions, momentum coupling induces velocity diffusion which is not destroyed by the spatial coupling. Spatial-momentum coupling may induce spatial subdiffusion. The thermodynamic equilibrium theory presented in this paper does not violate the second law of thermodynamics, although the average velocity squared of the particle may increase in time without bound.

  15. Hardware Acceleration for Cyber Security

    Science.gov (United States)

    2010-11-01

    adapters from Napatech [23]. Platforms provided by research comunity are COMBO cards [4] from CESNET and NetFPGA [24] cards from Stanford. Endace and... manager providing user interface on the client (SOC) side and the NETCONF agent applica- tion that controls configuration datastores on the device side. On...using NETCONF protocol. NETCONF uses simple Remote Procedure Call (RPC)-like approach to exchange messages between manager and agent application. This

  16. Effect of Accelerator in Green Synthesis of Silver Nanoparticles

    Directory of Open Access Journals (Sweden)

    Kamyar Shameli

    2010-10-01

    Full Text Available Silver nanoparticles (Ag-NPs were successfully synthesized in the natural polymeric matrix. Silver nitrate, gelatin, glucose, and sodium hydroxide have been used as silver precursor, stabilizer, reducing agent, and accelerator reagent, respectively. This study investigated the role of NaOH as the accelerator. The resultant products have been confirmed to be Ag-NPs using powder X-ray diffraction (PXRD, UV-vis spectroscopy, and transmission electron microscopy (TEM. The colloidal sols of Ag-NPs obtained at different volumes of NaOH show strong and different surface plasmon resonance (SPR peaks, which can be explained from the TEM images of Ag-NPs and their particle size distribution. Compared with other synthetic methods, this work is green, rapid, and simple to use. The newly prepared Ag-NPs may have many potential applications in chemical and biological industries.

  17. Ion Accelerator Merges Several Beams

    Science.gov (United States)

    Aston, G.

    1984-01-01

    Intense ion beam formed by merging multiple ion beamlets into one concentrated beam. Beamlet holes in graphite screen and focusing grids arranged in hexagonal pattern. Merged beam passes through single hole in each of aluminum accelerator and decelerator grids. Ion extraction efficiency, beam intensity, and focusing improved.

  18. Petawatt pulsed-power accelerator

    Science.gov (United States)

    Stygar, William A.; Cuneo, Michael E.; Headley, Daniel I.; Ives, Harry C.; Ives, legal representative; Berry Cottrell; Leeper, Ramon J.; Mazarakis, Michael G.; Olson, Craig L.; Porter, John L.; Wagoner; Tim C.

    2010-03-16

    A petawatt pulsed-power accelerator can be driven by various types of electrical-pulse generators, including conventional Marx generators and linear-transformer drivers. The pulsed-power accelerator can be configured to drive an electrical load from one- or two-sides. Various types of loads can be driven; for example, the accelerator can be used to drive a high-current z-pinch load. When driven by slow-pulse generators (e.g., conventional Marx generators), the accelerator comprises an oil section comprising at least one pulse-generator level having a plurality of pulse generators; a water section comprising a pulse-forming circuit for each pulse generator and a level of monolithic triplate radial-transmission-line impedance transformers, that have variable impedance profiles, for each pulse-generator level; and a vacuum section comprising triplate magnetically insulated transmission lines that feed an electrical load. When driven by LTD generators or other fast-pulse generators, the need for the pulse-forming circuits in the water section can be eliminated.

  19. High-current electron accelerator

    Science.gov (United States)

    Alekseyev, B. V.; Gorelikov, I. M.; Kazurov, V. I.; Mashkov, L. V.; Greshko, A. G.; Soklakov, G. I.; Fedorenko, A. I.; Yurekevich, K. B.

    1986-02-01

    A high current electron accelerator was developed and built on the basis of computer aided design calculations and electrolytic trough simulation. A 15 stage Arkadyev/Marx pulse voltage generator serves as the primary energy storing device. Each stage consists of two IK-100-0.4 capacitors connected in parallel and all immersed in transformer oil inside a metal container on electrically insulating posts. Each stage is shielded on both the positive and negative potential side. The shields, made of copper foil, not only smooth the electric field in the clearances but also constitute part of the commutating circuit and contribute to reduction of the overall generator size. The pulse voltage generator is triggered by a synchronizer through the conventional firing circuit of a TGI1-350/16 thyratron. To operate the accelerator in the nanosecond mode, the generator discharges into a diode through a twin shaping line. In this mode the accelerator can produce 0.8 MeV to 240 kA electron beams of 0.8 ns duration. To operate in the microsecond mode, the shaping line acts as storing capacitor, and the discharge gaps must be charged with polarity reversal in each stage. In this mode the accelerator can produce 0.5 MeV to 10 kA electron beams of 1 microsecond duration.

  20. CLIC Drive Beam Accelerating Structures

    CERN Document Server

    Wegner, Rolf

    2012-01-01

    Travelling structures for accelerating the high-current (4.2 A) CLIC Drive Beam to an energy of 2.37 GeV are presented. The structures are optimised for efficiency (full beam loading operation) and a desired filling time. Higher order modes are studied and are reduced by detuning along the structure and by damping with silicon carbide loads.

  1. CERNois wins prestigious accelerator award

    CERN Multimedia

    Katarina Anthony

    2011-01-01

    During the 2nd International Particle Accelerator Conference, CERN’s Rogelio Tomás García became the first Spaniard to receive the Frank Sacherer Prize for his work in particle beam optics.   Rogelio Tomás García at the 2nd International Particle Accelerator Conference. The Frank Sacherer Prize is awarded to physicists who have made a “significant, original contribution to the accelerator field" early on in their career. This year the prize was given to Rogelio Tomás García who, at only 35 years of age, has made important contributions to the optics design, optics measurement, and correction techniques applied at both the LHC and Brookhaven’s RHIC. “Tomás has had a vital impact on CERN’s beam optics studies and has made very impressive achievements in the field of beam optics,” says Oliver Brüning, Head of the Accelerators and Beam Physics...

  2. Thomas Jefferson National Accelerator Facility

    Energy Technology Data Exchange (ETDEWEB)

    Grames, Joseph; Higinbotham, Douglas; Montgomery, Hugh

    2010-09-08

    The Thomas Jefferson National Accelerator Facility (Jefferson Lab) in Newport News, Virginia, USA, is one of ten national laboratories under the aegis of the Office of Science of the U.S. Department of Energy (DOE). It is managed and operated by Jefferson Science Associates, LLC. The primary facility at Jefferson Lab is the Continuous Electron Beam Accelerator Facility (CEBAF) as shown in an aerial photograph in Figure 1. Jefferson Lab was created in 1984 as CEBAF and started operations for physics in 1995. The accelerator uses superconducting radio-frequency (srf) techniques to generate high-quality beams of electrons with high-intensity, well-controlled polarization. The technology has enabled ancillary facilities to be created. The CEBAF facility is used by an international user community of more than 1200 physicists for a program of exploration and study of nuclear, hadronic matter, the strong interaction and quantum chromodynamics. Additionally, the exceptional quality of the beams facilitates studies of the fundamental symmetries of nature, which complement those of atomic physics on the one hand and of high-energy particle physics on the other. The facility is in the midst of a project to double the energy of the facility and to enhance and expand its experimental facilities. Studies are also pursued with a Free-Electron Laser produced by an energy-recovering linear accelerator.

  3. Accelerated bridge paint test program.

    Science.gov (United States)

    2011-07-06

    The accelerated bridge paint (AB-Paint) program evaluated a new Sherwin-Williams two-coat, : fast-curing paint system. The system is comprised of an organic zinc-rich primer (SW Corothane I : Galvapac One-Pack Zinc-Rich Primer B65 G11) and a polyurea...

  4. Accelerator-Based Neutrino Beams

    OpenAIRE

    Hübner, K

    2003-01-01

    The design principles of accelerator-based neutrino beams are outlined and the beams currently in operation or under construction are briefly described. The concepts and basic features of the different types of advanced neutrino beams which are under study are summarized.

  5. Introduction to RF linear accelerators

    CERN Document Server

    Pichoff, N

    2006-01-01

    After a short introduction to applications of RF linacs and their advantages and drawbacks as opposed to circular accelerators, the model of RF resonant cavities and their excitation by RF sources or beam is introduced. Then beam dynamics notions, essential to linacs, such as transit-time factor, synchronism, r.m.s. properties, matching and mismatching in linear or nonlinear forces, are presented.

  6. Soundless Chemical Demolition Agents

    OpenAIRE

    ECT Team, Purdue

    2007-01-01

    The traditional approach to demolishing concrete structures or reducing the size of large rocks or boulders has typically included the use of explosives. The resulting explosions are associated with the obvious risks posed by shock waves and fly rock. Soundless chemical demolition agents (SCDAs) have proven to be viable substitutes for the use of explosives. SCDAs are powdery materials that will expand considerably when mixed with water.

  7. Accelerator applications in energy and security

    CERN Document Server

    Chou, Weiren

    2015-01-01

    As accelerator science and technology progressed over the past several decades, the accelerators themselves have undergone major improvements in multiple performance factors: beam energy, beam power, and beam brightness. As a consequence, accelerators have found applications in a wide range of fields in our life and in our society. The current volume is dedicated to applications in energy and security, two of the most important and urgent topics in today's world. This volume makes an effort to provide a review as complete and up to date as possible of this broad and challenging subject. It contains overviews on each of the two topics and a series of articles for in-depth discussions including heavy ion accelerator driven inertial fusion, linear accelerator-based ADS systems, circular accelerator-based ADS systems, accelerator-reactor interface, accelerators for fusion material testing, cargo inspection, proton radiography, compact neutron generators and detectors. It also has a review article on accelerator ...

  8. Technology and applications of advanced accelerator concepts

    CERN Document Server

    Chou, Weiren

    2016-01-01

    Since its invention in the 1920s, particle accelerators have made tremendous progress in accelerator science, technology and applications. However, the fundamental acceleration principle, namely, to apply an external radiofrequency (RF) electric field to accelerate charged particles, remains unchanged. As this method (either room temperature RF or superconducting RF) is approaching its intrinsic limitation in acceleration gradient (measured in MeV/m), it becomes apparent that new methods with much higher acceleration gradient (measured in GeV/m) must be found for future very high energy accelerators as well as future compact (table-top or room-size) accelerators. This volume introduces a number of advanced accelerator concepts (AAC) — their principles, technologies and potential applications. For the time being, none of them stands out as a definitive direction in which to go. But these novel ideas are in hot pursuit and look promising. Furthermore, some AAC requires a high power laser system. This has the ...

  9. CAS - CERN Accelerator School: Advanced Accelerator Physics Course

    CERN Document Server

    Herr, W

    2014-01-01

    This report presents the proceedings of the Course on Advanced Accelerator Physics organized by the CERN Accelerator School. The course was held in Trondheim, Norway from 18 to 29 August 2013, in collaboration with the Norwegian University of Science and Technology. Its syllabus was based on previous courses and in particular on the course held in Berlin 2003 whose proceedings were published as CERN Yellow Report CERN- 2006-002. The field has seen significant advances in recent years and some topics were presented in a new way and other topics were added. The lectures were supplemented with tutorials on key topics and 14 hours of hands on courses on Optics Design and Corrections, RF Measurement Techniques and Beam Instrumentation and Diagnostics. These courses are a key element of the Advanced Level Course.

  10. Constructing Secure Mobile Agent Systems Using the Agent Operating System

    NARCIS (Netherlands)

    van t Noordende, G.J.; Overeinder, B.J.; Timmer, R.J.; Brazier, F.M.; Tanenbaum, A.S.

    2009-01-01

    Designing a secure and reliable mobile agent system is a difficult task. The agent operating system (AOS) is a building block that simplifies this task. AOS provides common primitives required by most mobile agent middleware systems, such as primitives for secure communication, secure and

  11. Organizations as Socially Constructed Agents in the Agent Oriented Paradigm

    NARCIS (Netherlands)

    G. Boella (Guido); L.W.N. van der Torre (Leon)

    2005-01-01

    htmlabstractIn this paper we propose a new role for the agent metaphor in the definition of the organizational structure of multiagent systems. The agent metaphor is extended to consider as agents also social entities like organizations, groups and normative systems, so that mental attitudes can

  12. Fresnel diffraction patterns as accelerating beams

    CERN Document Server

    Zhang, Yiqi; Zheng, Huaibin; Wu, Zhenkun; Li, Yuanyuan; Lu, Keqing; Zhang, Yanpeng

    2013-01-01

    We demonstrate that beams originating from Fresnel diffraction patterns are self-accelerating in free space. In addition to accelerating and self-healing, they also exhibit parabolic deceleration property, which is in stark contrast to other accelerating beams. We find that the trajectory of Fresnel paraxial accelerating beams is similar to that of nonparaxial Weber beams. Decelerating and accelerating regions are separated by a critical propagation distance, at which no acceleration is present. During deceleration, the Fresnel diffraction beams undergo self-smoothing, in which oscillations of the diffracted waves gradually focus and smooth out at the critical distance.

  13. Observation of acceleration and deceleration in gigaelectron-volt-per-metre gradient dielectric wakefield accelerators

    National Research Council Canada - National Science Library

    O'Shea, B D; Andonian, G; Barber, S K; Fitzmorris, K L; Hakimi, S; Harrison, J; Hoang, P D; Hogan, M J; Naranjo, B; Williams, O B; Yakimenko, V; Rosenzweig, J B

    2016-01-01

    .... To address this need, short wavelength accelerators based on wakefields, where an intense relativistic electron beam radiates the demanded fields directly into the accelerator structure or medium...

  14. The Power Trading Agent Competition

    NARCIS (Netherlands)

    W. Ketter (Wolfgang); J. Collins (John); P. Reddy (Prashant); C. Flath (Christoph)

    2011-01-01

    textabstractThis is the specification for the Power Trading Agent Competition for 2011 (Power TAC 2011). Agents are simulations of electrical power brokers, who must compete with each other for both power production and consumption, and manage their portfolios.

  15. Accelerate!

    Science.gov (United States)

    Kotter, John P

    2012-11-01

    The old ways of setting and implementing strategy are failing us, writes the author of Leading Change, in part because we can no longer keep up with the pace of change. Organizational leaders are torn between trying to stay ahead of increasingly fierce competition and needing to deliver this year's results. Although traditional hierarchies and managerial processes--the components of a company's "operating system"--can meet the daily demands of running an enterprise, they are rarely equipped to identify important hazards quickly, formulate creative strategic initiatives nimbly, and implement them speedily. The solution Kotter offers is a second system--an agile, networklike structure--that operates in concert with the first to create a dual operating system. In such a system the hierarchy can hand off the pursuit of big strategic initiatives to the strategy network, freeing itself to focus on incremental changes to improve efficiency. The network is populated by employees from all levels of the organization, giving it organizational knowledge, relationships, credibility, and influence. It can Liberate information from silos with ease. It has a dynamic structure free of bureaucratic layers, permitting a level of individualism, creativity, and innovation beyond the reach of any hierarchy. The network's core is a guiding coalition that represents each level and department in the hierarchy, with a broad range of skills. Its drivers are members of a "volunteer army" who are energized by and committed to the coalition's vividly formulated, high-stakes vision and strategy. Kotter has helped eight organizations, public and private, build dual operating systems over the past three years. He predicts that such systems will lead to long-term success in the 21st century--for shareholders, customers, employees, and companies themselves.

  16. Collaborating with Autonomous Agents

    Science.gov (United States)

    Trujillo, Anna C.; Cross, Charles D.; Fan, Henry; Hempley, Lucas E.; Motter, Mark A.; Neilan, James H.; Qualls, Garry D.; Rothhaar, Paul M.; Tran, Loc D.; Allen, B. Danette

    2015-01-01

    With the anticipated increase of small unmanned aircraft systems (sUAS) entering into the National Airspace System, it is highly likely that vehicle operators will be teaming with fleets of small autonomous vehicles. The small vehicles may consist of sUAS, which are 55 pounds or less that typically will y at altitudes 400 feet and below, and small ground vehicles typically operating in buildings or defined small campuses. Typically, the vehicle operators are not concerned with manual control of the vehicle; instead they are concerned with the overall mission. In order for this vision of high-level mission operators working with fleets of vehicles to come to fruition, many human factors related challenges must be investigated and solved. First, the interface between the human operator and the autonomous agent must be at a level that the operator needs and the agents can understand. This paper details the natural language human factors e orts that NASA Langley's Autonomy Incubator is focusing on. In particular these e orts focus on allowing the operator to interact with the system using speech and gestures rather than a mouse and keyboard. With this ability of the system to understand both speech and gestures, operators not familiar with the vehicle dynamics will be able to easily plan, initiate, and change missions using a language familiar to them rather than having to learn and converse in the vehicle's language. This will foster better teaming between the operator and the autonomous agent which will help lower workload, increase situation awareness, and improve performance of the system as a whole.

  17. Agentes selladores en endodoncia

    OpenAIRE

    Racciatti, Gabriela

    2003-01-01

    Recibido: Noviembre 2002 Aceptado: Enero 2003 La gutapercha sigue siendo uno de los materiales predilectos, pero debido a su falta de adhesión a las paredes dentinarias, debe estar siempre combinada con un sellador que actúe como interfase entre la masa de gutapercha y la estructura dentaria. El uso de un agente sellador para obturar los conductos radiculares es esencial para el éxito del proceso de obturación. Un buen sellador debe ser biocompatible y bien tolerado por los tejid...

  18. Chemical warfare agents

    Directory of Open Access Journals (Sweden)

    Vijayaraghavan R

    2010-01-01

    Full Text Available Among the Weapons of Mass Destruction, chemical warfare (CW is probably one of the most brutal created by mankind in comparison with biological and nuclear warfare. Chemical weapons are inexpensive and are relatively easy to produce, even by small terrorist groups, to create mass casualties with small quantities. The characteristics of various CW agents, general information relevant to current physical as well as medical protection methods, detection equipment available and decontamination techniques are discussed in this review article. A brief note on Chemical Weapons Convention is also provided.

  19. Teaching tourism change agents

    OpenAIRE

    Stilling Blichfeldt, Bodil; Kvistgaard, Hans-Peter; Hird, John

    2017-01-01

    This article discuss es know ledge, competencies and skills Master’s students should obtain during their academic studies and particularly, the differences between teaching about a topic and teaching to do. This is ex emplified by experiential learning theory and the case of a change management course that is part of a Tourism Master’s program, where a major challenge is not only to teach students about change and change agents, but to teach them how change feels and ho w to become change age...

  20. Toxorhynchites as biocontrol agents.

    Science.gov (United States)

    Focks, Dana A

    2007-01-01

    Toxorhynchites is an unusual and interesting genus of large, non-biting mosquitoes. In spite of their size, they are--like many species of mosquitoes--completely harmless to man. The larvae are predaceous on other mosquitoes and aquatic organisms that inhabit both natural and artificial containers. Because this habitat is the source of several medically important species of mosquitoes, there is warrant for evaluating the potential of Toxorhynchites as a biological control agent under various conditions. Toxorhynchites is not seen as a panacea for the control of all container-inhabiting mosquitoes. However, it has demonstrated practical potential in certain restricted but important situations.

  1. Elementary principles of linear accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Loew, G.A.; Talman, R.

    1983-09-01

    These lectures come in five sections. The first is this introduction. The second is a short chronology of what are viewed as important milestones in the field. The third covers proton linacs. It introduces elementary concepts such as transit time, shunt impedance, and Q. Critical issues such as phase stability and transverse forces are discussed. The fourth section contains an elementary discussion of waveguide accelerating structures. It can be regarded as an introduction to some of the more advanced treatments of the subject. The final section is devoted to electron accelerators. Taking SLAC as an example, various topics are discussed such as structure design, choice of parameters, frequency optimization, beam current, emittance, bunch length and beam loading. Recent developments and future challenges are mentioned briefly. 41 figures, 4 tables.

  2. History of hadron therapy accelerators.

    Science.gov (United States)

    Degiovanni, Alberto; Amaldi, Ugo

    2015-06-01

    In the last 60 years, hadron therapy has made great advances passing from a stage of pure research to a well-established treatment modality for solid tumours. In this paper the history of hadron therapy accelerators is reviewed, starting from the first cyclotrons used in the thirties for neutron therapy and passing to more modern and flexible machines used nowadays. The technical developments have been accompanied by clinical studies that allowed the selection of the tumours which are more sensitive to this type of radiotherapy. This paper aims at giving a review of the origin and the present status of hadron therapy accelerators, describing the technological basis and the continuous development of this application to medicine of instruments developed for fundamental science. At the end the present challenges are reviewed. Copyright © 2015 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

  3. Industrial applications of electron accelerators

    CERN Document Server

    Cleland, M R

    2006-01-01

    This paper addresses the industrial applications of electron accelerators for modifying the physical, chemical or biological properties of materials and commercial products by treatment with ionizing radiation. Many beneficial effects can be obtained with these methods, which are known as radiation processing. The earliest practical applications occurred during the 1950s, and the business of radiation processing has been expanding since that time. The most prevalent applications are the modification of many different plastic and rubber products and the sterilization of single-use medical devices. Emerging applications are the pasteurization and preservation of foods and the treatment of toxic industrial wastes. Industrial accelerators can now provide electron energies greater than 10 MeV and average beam powers as high as 700 kW. The availability of high-energy, high-power electron beams is stimulating interest in the use of X-rays (bremsstrahlung) as an alternative to gamma rays from radioactive nuclides.

  4. Airbreathing Acceleration Toward Earth Orbit

    Energy Technology Data Exchange (ETDEWEB)

    Whitehead, J C

    2007-05-09

    As flight speed increases, aerodynamic drag rises more sharply than the availability of atmospheric oxygen. The ratio of oxygen mass flux to dynamic pressure cannot be improved by changing altitude. The maximum possible speed for airbreathing propulsion is limited by the ratio of air capture area to vehicle drag area, approximately Mach 6 at equal areas. Simulation of vehicle acceleration shows that the use of atmospheric oxygen offers a significant potential for minimizing onboard consumables at low speeds. These fundamental calculations indicate that a practical airbreathing launch vehicle would accelerate to near steady-state speed while consuming only onboard fuel, then transition to rocket propulsion. It is suggested that an aircraft carrying a rocket-propelled vehicle to approximately Mach 5 could be a realistic technical goal toward improving access to orbit.

  5. Greece welcomes CERN Accelerator School

    CERN Multimedia

    CAS School

    2011-01-01

    The CERN Accelerator School (CAS) and the University of the Aegean jointly organised a course on intermediate-level Accelerator Physics in Chios, Greece, from 19 to 30 September, 2011.   CAS Students pose for a group photo in Chios, Greece. This course followed the established format of the intermediate school, with lectures in the mornings and specialised courses in the afternoons. The latter provided “hands-on” education and experience in three topics: “RF Measurement Techniques”, “Beam Instrumentation and Diagnostics” and “Optics Design and Correction”.  Participants selected one of the three courses and followed the chosen topic throughout the school. Guided studies and tutorials on core subjects, seminars and a poster session completed the programme. An excursion included a visit to the Nea Moni monastery, a guided tour of two medieval villages, Pyrgi and Mesta, and finished with a typical Greek me...

  6. The US Muon Accelerator Program

    Energy Technology Data Exchange (ETDEWEB)

    Torun, Y.; /IIT, Chicago; Kirk, H.; /Brookhaven; Bross, A.; Geer, Steve; Shiltsev, Vladimir; /Fermilab; Zisman, M.; /LBL, Berkeley

    2010-05-01

    An accelerator complex that can produce ultra-intense beams of muons presents many opportunities to explore new physics. A facility of this type is unique in that, in a relatively straightforward way, it can present a physics program that can be staged and thus move forward incrementally, addressing exciting new physics at each step. At the request of the US Department of Energy's Office of High Energy Physics, the Neutrino Factory and Muon Collider Collaboration (NFMCC) and the Fermilab Muon Collider Task Force (MCTF) have recently submitted a proposal to create a Muon Accelerator Program that will have, as a primary goal, to deliver a Design Feasibility Study for an energy-frontier Muon Collider by the end of a 7 year R&D program. This paper presents a description of a Muon Collider facility and gives an overview of the proposal.

  7. Hardware-Accelerated Simulated Radiography

    Energy Technology Data Exchange (ETDEWEB)

    Laney, D; Callahan, S; Max, N; Silva, C; Langer, S; Frank, R

    2005-08-04

    We present the application of hardware accelerated volume rendering algorithms to the simulation of radiographs as an aid to scientists designing experiments, validating simulation codes, and understanding experimental data. The techniques presented take advantage of 32-bit floating point texture capabilities to obtain solutions to the radiative transport equation for X-rays. The hardware accelerated solutions are accurate enough to enable scientists to explore the experimental design space with greater efficiency than the methods currently in use. An unsorted hexahedron projection algorithm is presented for curvilinear hexahedral meshes that produces simulated radiographs in the absorption-only regime. A sorted tetrahedral projection algorithm is presented that simulates radiographs of emissive materials. We apply the tetrahedral projection algorithm to the simulation of experimental diagnostics for inertial confinement fusion experiments on a laser at the University of Rochester.

  8. A Characterization of Sapient Agents

    NARCIS (Netherlands)

    van Otterlo, M.; Wiering, Marco; Dastani, Mehdi; Meyer, John-Jules; Hexmoor, H.

    2003-01-01

    This paper presents a proposal to characterize Sapient Agents in terms of cognitive concepts and abilities. In particular, a sapient agent is considered as a cognitive agent the learns its cognitive state and capabilities through experience. This characterization is based on formal concepts such as

  9. Motivating agents in software tutorials

    NARCIS (Netherlands)

    van der Meij, Hans

    2013-01-01

    Pedagogical agents can provide important support for the user in human–computer interaction systems. This paper examines whether a supplementary, motivating agent in a print tutorial can enhance student motivation and learning in software training. The agent served the role of motivator, attending

  10. Cultural Differentiation of Negotiating Agents

    NARCIS (Netherlands)

    Hofstede, G.J.; Jonker, C.M.; Verwaart, D.

    2012-01-01

    Negotiations proceed differently across cultures. For realistic modeling of agents in multicultural negotiations, the agents must display culturally differentiated behavior. This paper presents an agent-based simulation model that tackles these challenges, based on Hofstede’s model of national

  11. Cultural differentiation of negotiating agents

    NARCIS (Netherlands)

    Hofstede, G.J.; Jonker, C.M.; Verwaart, T.

    2010-01-01

    Negotiations proceed differently across cultures. For realistic modeling of agents in multicultural negotiations, the agents must display culturally differentiated behavior. This paper presents an agent-based simulation model that tackles these challenges, based on Hofstede’s model of national

  12. A logic for agent organizations

    NARCIS (Netherlands)

    Dignum, M.V.; Dignum, F.P.M.

    2007-01-01

    Organization concepts and models are increasingly being adopted for the design and specification of multi-agent systems. Agent organizations can be seen as mechanisms of social order, created to achieve common goals for more or less autonomous agents. In order to develop a theory on the relation

  13. Extinction Events Can Accelerate Evolution

    OpenAIRE

    Joel Lehman; Risto Miikkulainen

    2015-01-01

    Extinction events impact the trajectory of biological evolution significantly. They are often viewed as upheavals to the evolutionary process. In contrast, this paper supports the hypothesis that although they are unpredictably destructive, extinction events may in the long term accelerate evolution by increasing evolvability. In particular, if extinction events extinguish indiscriminately many ways of life, indirectly they may select for the ability to expand rapidly through vacated niches. ...

  14. Accelerated Metals Development by Computation

    Science.gov (United States)

    2008-02-01

    Laboratory (AFRL) “Science and Technology Workforce for the 21st Century ( STW -21)” initiative to shape the AFRL science and engineer workforce by...providing workforce agility and responsiveness to deal with dynamic technical and resource challenges. The goal was to provide the opportunity for...allowed AFRL/RX to augment its staff, facilities, and equipment by leveraging the resources of OSU. This program focused on accelerating materials

  15. Research in accelerator physics (theory)

    Science.gov (United States)

    Ohnuma, Shoroku

    1991-01-01

    This report discusses the following topics: beam-beam interaction in colliders with momentum oscillation; isolated difference resonance and evolution of the particle distribution; study of magnet sorting for the SSC High Energy Booster; development of a discrete HESQ; beam dynamics in compact synchrotrons; theoretical problems in multi-stage FEL for two-beam acceleration; operation of Tevatron near integer tunes; and detailed examination of coupling impedance of various devices in storage rings; impact on beams from the insertion devices.

  16. Accelerating Universe via Spatial Averaging

    OpenAIRE

    Nambu, Yasusada; TANIMOTO, Masayuki

    2005-01-01

    We present a model of an inhomogeneous universe that leads to accelerated expansion after taking spatial averaging. The model universe is the Tolman-Bondi solution of the Einstein equation and contains both a region with positive spatial curvature and a region with negative spatial curvature. We find that after the region with positive spatial curvature begins to re-collapse, the deceleration parameter of the spatially averaged universe becomes negative and the averaged universe starts accele...

  17. An accelerator worth fighting for

    CERN Multimedia

    1996-01-01

    Financial pressures from member states have upset the calculations of the European Laboratory for Particle Physics's (CERN) major accelerator, the Large Hadron Collider (LHC). Despite preference for domestic high energy programs, CERN members accord high priority to LHC physics. Converting to a global facility can help spread the high annual cost of subscription. But given the political realities, a revision of the LHC project appears more feasible. CERN's management needs to deploy its skills to overcome the financial obstacles to the facility.

  18. Status of JAERI tandem accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Yoshida, Tadashi; Kanda, Susumu; Takeuchi, Suehiro [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment] (and others)

    2001-02-01

    JAERI Tandem Accelerator had been operated approximately 230 days in fiscal year of 1999. Meanwhile, we had three times of maintenance period with vent. Total operation-times were 5273 hours. We could not carry out the experiment using rare gas, due to malfunction of the RF power supply for the ECR ion source. The type of the RF power supply is peculiar and it is impossible to get spare parts for repair. We are now investigating the backup RF power supply. The power supply for the magnet became unstable due to degradation of insulation in the shunt resistance, which is used for feedback stabilization. Stability was recovered after cleaning. The acrylic resin shaft was cracked. This cracks have a potential for severe accidents. So far bearing of the shaft has no problem. The reason of cracks may be self-destruction by charge accumulation in the shaft. JAERI Tandem Accelerator is approximately 20 years old. There appear requirements on the higher ion currents for additional ion species. Therefore, authors are investigating cost effective improvement plans of RFQ (Radio Frequency Quadra-pole) and IH type accelerator based on KEK (High Energy Accelerator Research Organization) R and D. As a whole, maintenance services for the control system are increasing due to some changes of computer programs. There are some difficulties to keep skilled personnel for facilities operation. Authors are gradually increasing hired personnel with contract from 1993. However, loads for JAERI permanent staffs are still heavy. It takes much longer time to educate skilled persons especially for safety. (Y. Tanaka)

  19. Accelerator x-ray sources

    CERN Document Server

    Talman, Richard

    2007-01-01

    This first book to cover in-depth the generation of x-rays in particle accelerators focuses on electron beams produced by means of the novel Energy Recovery Linac (ERL) technology. The resulting highly brilliant x-rays are at the centre of this monograph, which continues where other books on the market stop. Written primarily for general, high energy and radiation physicists, the systematic treatment adopted by the work makes it equally suitable as an advanced textbook for young researchers.

  20. JACoW Decoupling CERN accelerators

    CERN Document Server

    Dworak, Andrzej

    2018-01-01

    The accelerator complex at CERN is a living system. Accelerators are being dismantled, upgraded or change their purpose. New accelerators are built. The changes do not happen overnight, but when they happen they may require profound changes across the handling systems. Central timings (CT), responsible for sequencing and synchronization of accelerators, are good examples of such systems. This paper shows how over the past twenty years the changes and new requirements influenced the evolution of the CTs. It describes experience gained from using the Central Beam and Cycle Manager (CBCM) CT model, for strongly coupled accelerators, and how it led to a design of a new Dynamic Beam Negotiation (DBN) model for the AD and ELENA accelerators, which reduces the coupling, increasing accelerator independence. The paper ends with an idea how to merge strong points of both models in order to create a single generic system able to efficiently handle all CERN accelerators and provide more beam time to experiments and LHC.

  1. A Critical Theory Perspective on Accelerated Learning.

    Science.gov (United States)

    Brookfield, Stephen D.

    2003-01-01

    Critically analyzes accelerated learning using concepts from Herbert Marcuse (rebellious subjectivity) and Erich Fromm (automaton conformity). Concludes that, by providing distance and separation, accelerated learning has more potential to stimulate critical autonomous thought. (SK)

  2. Berkeley Lab Laser Accelerator (BELLA) facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Berkeley Lab Laser Accelerator (BELLA) facility (formerly LOASIS) develops advanced accelerators and radiation sources. High gradient (1-100 GV/m) laser-plasma...

  3. Accelerator Technology Division: Annual Report FY 1990

    National Research Council Canada - National Science Library

    Schriber, Stanley

    1991-01-01

    The Accelerator Technology (AT) Division continued in fiscal year 1990 to fulfill its mission of developing accelerator science and technology for application to research, defense, energy, and other problems of national interest...

  4. Accelerated Cure Project for Multiple Sclerosis

    Science.gov (United States)

    ... content Accelerating research toward a cure for multiple sclerosis Toggle navigation Search form Search Connect Volunteer Donate ... to accelerate efforts toward a cure for multiple sclerosis by rapidly advancing research that determines its causes ...

  5. Cavitation onset caused by acceleration.

    Science.gov (United States)

    Pan, Zhao; Kiyama, Akihito; Tagawa, Yoshiyuki; Daily, David J; Thomson, Scott L; Hurd, Randy; Truscott, Tadd T

    2017-07-24

    Striking the top of a liquid-filled bottle can shatter the bottom. An intuitive interpretation of this event might label an impulsive force as the culprit in this fracturing phenomenon. However, high-speed photography reveals the formation and collapse of tiny bubbles near the bottom before fracture. This observation indicates that the damaging phenomenon of cavitation is at fault. Cavitation is well known for causing damage in various applications including pipes and ship propellers, making accurate prediction of cavitation onset vital in several industries. However, the conventional cavitation number as a function of velocity incorrectly predicts the cavitation onset caused by acceleration. This unexplained discrepancy leads to the derivation of an alternative dimensionless term from the equation of motion, predicting cavitation as a function of acceleration and fluid depth rather than velocity. Two independent research groups in different countries have tested this theory; separate series of experiments confirm that an alternative cavitation number, presented in this paper, defines the universal criteria for the onset of acceleration-induced cavitation.

  6. LEP superconducting accelerating cavity module

    CERN Multimedia

    1995-01-01

    With its 27-kilometre circumference, the Large Electron-Positron (LEP) collider was the largest electron-positron accelerator ever built. The excavation of the LEP tunnel was Europe’s largest civil-engineering project prior to the Channel Tunnel. Three tunnel-boring machines started excavating the tunnel in February 1985 and the ring was completed three years later. In its first phase of operation, LEP consisted of 5176 magnets and 128 accelerating cavities. CERN’s accelerator complex provided the particles and four enormous detectors, ALEPH, DELPHI, L3 and OPAL, observed the collisions. LEP was commissioned in July 1989 and the first beam circulated in the collider on 14 July. The collider's initial energy was chosen to be around 91 GeV, so that Z bosons could be produced. The Z boson and its charged partner the W boson, both discovered at CERN in 1983, are responsible for the weak force, which drives the Sun, for example. Observing the creation and decay of the short-lived Z boson was a critical test of...

  7. Cavitation onset caused by acceleration

    Science.gov (United States)

    Pan, Zhao; Kiyama, Akihito; Tagawa, Yoshiyuki; Daily, David J.; Thomson, Scott L.; Hurd, Randy; Truscott, Tadd T.

    2017-08-01

    Striking the top of a liquid-filled bottle can shatter the bottom. An intuitive interpretation of this event might label an impulsive force as the culprit in this fracturing phenomenon. However, high-speed photography reveals the formation and collapse of tiny bubbles near the bottom before fracture. This observation indicates that the damaging phenomenon of cavitation is at fault. Cavitation is well known for causing damage in various applications including pipes and ship propellers, making accurate prediction of cavitation onset vital in several industries. However, the conventional cavitation number as a function of velocity incorrectly predicts the cavitation onset caused by acceleration. This unexplained discrepancy leads to the derivation of an alternative dimensionless term from the equation of motion, predicting cavitation as a function of acceleration and fluid depth rather than velocity. Two independent research groups in different countries have tested this theory; separate series of experiments confirm that an alternative cavitation number, presented in this paper, defines the universal criteria for the onset of acceleration-induced cavitation.

  8. Low voltage electron beam accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Ochi, Masafumi [Iwasaki Electric Co., Ltd., Tokyo (Japan)

    2003-02-01

    Widely used electron accelerators in industries are the electron beams with acceleration voltage at 300 kV or less. The typical examples are shown on manufactures in Japan, equipment configuration, operation, determination of process parameters, and basic maintenance requirement of the electron beam processors. New electron beam processors with acceleration voltage around 100 kV were introduced maintaining the relatively high dose speed capability of around 10,000 kGy x mpm at production by ESI (Energy Science Inc. USA, Iwasaki Electric Group). The application field like printing and coating for packaging requires treating thickness of 30 micron or less. It does not require high voltage over 110 kV. Also recently developed is a miniature bulb type electron beam tube with energy less than 60 kV. The new application area for this new electron beam tube is being searched. The drive force of this technology to spread in the industries would be further development of new application, process and market as well as the price reduction of the equipment, upon which further acknowledgement and acceptance of the technology to societies and industries would entirely depend. (Y. Tanaka)

  9. Injector Design for Advanced Accelerators

    Science.gov (United States)

    Henestroza, Enrique; Faltens, A.

    1996-11-01

    Accelerator designs intended to provide acceleration at a much lower cost per Joule than the ILSE or ELISE designs are under study. For these designs, which typically have many beams, an injector of significantly lower cost is needed. A goal, which from our design appears to be achievable, is to reduce the transverse dimension to half that of the 2 MeV, 800 mA ILSE injector(E. Henestroza, ``Injectors for Heavy Ion Fusion", Proc. of the 11th International Wkshp. on Laser Interaction and Related Plasma Phenomena, 1993.) while generating about the same current. A single channel of a lower cost injector includes an 800 kV column, accelerating a 700 mA beam extracted from a potassium source of 4 cm radius by a 120 kV electrode. The beam passes into a superconducting 7 T solenoid of 15 cm aperture and 15 cm length. This high-field solenoid provides the focusing needed for a small beam without increasing the electric field gradient. The injector and its matching section, also designed, fit within a 12 cm radius, which is small enough to allow construction of attractive multi-beam injectors. We will present solutions for the generation and transport of 700 mA potassium beams of up to 1.6 MeV within the same transverse constraint.

  10. High Power Electron Accelerator Prototype

    CERN Document Server

    Tkachenko, Vadim; Cheskidov, Vladimir; Korobeynikov, G I; Kuznetsov, Gennady I; Lukin, A N; Makarov, Ivan; Ostreiko, Gennady; Panfilov, Alexander; Sidorov, Alexey; Tarnetsky, Vladimir V; Tiunov, Michael A

    2005-01-01

    In recent time the new powerful industrial electron accelerators appear on market. It caused the increased interest to radiation technologies using high energy X-rays due to their high penetration ability. However, because of low efficiency of X-ray conversion for electrons with energy below 5 MeV, the intensity of X-rays required for some industrial applications can be achieved only when the beam power exceeds 300 kW. The report describes a project of industrial electron accelerator ILU-12 for electron energy up to 5 MeV and beam power up to 300 kW specially designed for use in industrial applications. On the first stage of work we plan to use the existing generator designed for ILU-8 accelerator. It is realized on the GI-50A triode and provides the pulse power up to 1.5-2 MW and up to 20-30 kW of average power. In the report the basic concepts and a condition of the project for today are reflected.

  11. GPU-Accelerated Text Mining

    Energy Technology Data Exchange (ETDEWEB)

    Cui, Xiaohui [ORNL; Mueller, Frank [North Carolina State University; Zhang, Yongpeng [ORNL; Potok, Thomas E [ORNL

    2009-01-01

    Accelerating hardware devices represent a novel promise for improving the performance for many problem domains but it is not clear for which domains what accelerators are suitable. While there is no room in general-purpose processor design to significantly increase the processor frequency, developers are instead resorting to multi-core chips duplicating conventional computing capabilities on a single die. Yet, accelerators offer more radical designs with a much higher level of parallelism and novel programming environments. This present work assesses the viability of text mining on CUDA. Text mining is one of the key concepts that has become prominent as an effective means to index the Internet, but its applications range beyond this scope and extend to providing document similarity metrics, the subject of this work. We have developed and optimized text search algorithms for GPUs to exploit their potential for massive data processing. We discuss the algorithmic challenges of parallelization for text search problems on GPUs and demonstrate the potential of these devices in experiments by reporting significant speedups. Our study may be one of the first to assess more complex text search problems for suitability for GPU devices, and it may also be one of the first to exploit and report on atomic instruction usage that have recently become available in NVIDIA devices.

  12. Analytical tools in accelerator physics

    Energy Technology Data Exchange (ETDEWEB)

    Litvinenko, V.N.

    2010-09-01

    This paper is a sub-set of my lectures presented in the Accelerator Physics course (USPAS, Santa Rosa, California, January 14-25, 2008). It is based on my notes I wrote during period from 1976 to 1979 in Novosibirsk. Only few copies (in Russian) were distributed to my colleagues in Novosibirsk Institute of Nuclear Physics. The goal of these notes is a complete description starting from the arbitrary reference orbit, explicit expressions for 4-potential and accelerator Hamiltonian and finishing with parameterization with action and angle variables. To a large degree follow logic developed in Theory of Cyclic Particle Accelerators by A.A.Kolmensky and A.N.Lebedev [Kolomensky], but going beyond the book in a number of directions. One of unusual feature is these notes use of matrix function and Sylvester formula for calculating matrices of arbitrary elements. Teaching the USPAS course motivated me to translate significant part of my notes into the English. I also included some introductory materials following Classical Theory of Fields by L.D. Landau and E.M. Liftsitz [Landau]. A large number of short notes covering various techniques are placed in the Appendices.

  13. Compensation Techniques in Accelerator Physics

    Energy Technology Data Exchange (ETDEWEB)

    Sayed, Hisham Kamal [Old Dominion Univ., Norfolk, VA (United States)

    2011-05-01

    Accelerator physics is one of the most diverse multidisciplinary fields of physics, wherein the dynamics of particle beams is studied. It takes more than the understanding of basic electromagnetic interactions to be able to predict the beam dynamics, and to be able to develop new techniques to produce, maintain, and deliver high quality beams for different applications. In this work, some basic theory regarding particle beam dynamics in accelerators will be presented. This basic theory, along with applying state of the art techniques in beam dynamics will be used in this dissertation to study and solve accelerator physics problems. Two problems involving compensation are studied in the context of the MEIC (Medium Energy Electron Ion Collider) project at Jefferson Laboratory. Several chromaticity (the energy dependence of the particle tune) compensation methods are evaluated numerically and deployed in a figure eight ring designed for the electrons in the collider. Furthermore, transverse coupling optics have been developed to compensate the coupling introduced by the spin rotators in the MEIC electron ring design.

  14. Accelerated Hypertension after Venlafaxine Usage

    Directory of Open Access Journals (Sweden)

    Yüksel Kıvrak

    2014-01-01

    Full Text Available Venlafaxine is the first antidepressant that acts via inhibiting serotonin and noradrenaline reuptake. Hypertension is observed in doses exceeding 300 mg/day and is the most feared complication. We report a patient with accelerated hypertension after venlafaxine use observed at a dose of 150 mg/day. A 23-year-old patient with symptoms of insomnia, depression, anhedonia, fatigue admitted our clinic. Venlafaxine at a dose of 75 mg/day was initiated after he was diagnosed with major depressive disorder. After 5 months, venlafaxine dose was uptitrated to 150 mg/day due to inadequate response to drug. After using venlafaxine for ten months at the dose of 150 mg/day, he admitted our clinic with headache and epistaxis. He was hospitalized after his blood pressure was measured as 210/170 mmHg. No secondary causes for hypertension were found, and venlafaxine treatment was considered possible etiologic factor. After stopping venlafaxine treatment, his blood pressure was reverted back to normal limits. While mild elevation of blood pressure could be observed after venlafaxine treatment, this case shows that accelerated hypertension with a diastolic blood pressure rise above 120 mmHg could be observed at relatively low doses of venlafaxine. Close monitoring of blood pressure is necessary after initiation of treatment, as accelerated hypertension could cause endorgan damage with potentially catastrophic results.

  15. Amphoteric surface active agents

    Directory of Open Access Journals (Sweden)

    Eissa, A.M. F.

    1995-10-01

    Full Text Available 2-[trimethyl ammonium, triethyl ammonium, pyridinium and 2-amino pyridinium] alkanoates, four series of surface active agents containing carbon chain C12, C14, C16 and C18carbon atoms, were prepared. Their structures were characterized by microanalysis, infrared (IR and nuclear magnetic resonance (NMR. Surface and interfacial tension, Krafft point, wetting time, emulsification power, foaming height and critical micelle concentration (cmc were determined and a comparative study was made between their chemical structure and surface active properties. Antimicrobial activity of these surfactants was also determined.

    Se prepararon cuatro series de agentes tensioactivos del tipo 2-[trimetil amonio, trietil amonio, piridinio y 2-amino piridinio] alcanoatos, que contienen cadenas carbonadas con C12, C14, C16 y C18 átomos de carbono.
    Se determinaron la tensión superficial e interfacial, el punto de Krafft, el tiempo humectante, el poder de emulsionamiento, la altura espumante y la concentración critica de miscela (cmc y se hizo un estudio comparativo entre la estructura química y sus propiedades tensioactivas. Se determinó también la actividad antimicrobiana de estos tensioactivos. Estas estructuras se caracterizaron por microanálisis, infrarrojo (IR y resonancia magnética nuclear (RMN.

  16. Holograms as Teaching Agents

    Science.gov (United States)

    Walker, Robin A.

    2013-02-01

    Hungarian physicist Dennis Gabor won the Pulitzer Prize for his 1947 introduction of basic holographic principles, but it was not until the invention of the laser in 1960 that research scientists, physicians, technologists and the general public began to seriously consider the interdisciplinary potentiality of holography. Questions around whether and when Three-Dimensional (3-D) images and systems would impact American entertainment and the arts would be answered before educators, instructional designers and students would discover how much Three-Dimensional Hologram Technology (3DHT) would affect teaching practices and learning environments. In the following International Symposium on Display Holograms (ISDH) poster presentation, the author features a traditional board game as well as a reflection hologram to illustrate conventional and evolving Three-Dimensional representations and technology for education. Using elements from the American children's toy Operation® (Hasbro, 2005) as well as a reflection hologram of a human brain (Ko, 1998), this poster design highlights the pedagogical effects of 3-D images, games and systems on learning science. As teaching agents, holograms can be considered substitutes for real objects, (human beings, organs, and animated characters) as well as agents (pedagogical, avatars, reflective) in various learning environments using many systems (direct, emergent, augmented reality) and electronic tools (cellphones, computers, tablets, television). In order to understand the particular importance of utilizing holography in school, clinical and public settings, the author identifies advantages and benefits of using 3-D images and technology as instructional tools.

  17. Sao Paulo pelletron accelerator: fortieth anniversary

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, Dirceu [Universidade de Sao Paulo (IF/USP), SP (Brazil). Inst. de Fisica

    2012-07-01

    Full text: This year the 8MV Sao Paulo Pelletron tandem accelerator completes 40 years . This electrostatic accelerator was installed in the Sao Paulo University in 1972 , and it was the first of this model constructed the National Electrostatic Corporation with several innovations particularly with respect to the new concept of accelerator tube and the charge system. In the talk will be discussed the performance of the accelerator during all these years and the main result scientific results. (author)

  18. Accelerated rotation with orbital angular momentum modes

    CSIR Research Space (South Africa)

    Schulze, C

    2015-04-01

    Full Text Available . As the angular acceleration takes place in a bounded space, the azimuthal degree of freedom, such fields accelerate periodically as they propagate. Notably, the amount of angular acceleration is not limited by paraxial considerations, may be tailored for large...

  19. Figuring the Acceleration of the Simple Pendulum

    Science.gov (United States)

    Lieberherr, Martin

    2011-01-01

    The centripetal acceleration has been known since Huygens' (1659) and Newton's (1684) time. The physics to calculate the acceleration of a simple pendulum has been around for more than 300 years, and a fairly complete treatise has been given by C. Schwarz in this journal. But sentences like "the acceleration is always directed towards the…

  20. Effective Teaching in Accelerated Learning Programs

    Science.gov (United States)

    Boyd, Drick

    2004-01-01

    According to Wlodkowski (2003), "accelerated learning programs are one of the fastest growing transformations in higher education" (p. 5). The Center for the Study of Accelerated Learning at Regis University has documented at least 250 colleges or universities that offer accelerated learning programs for working adults. By definition, accelerated…

  1. An Annotated Bibliography of Accelerated Learning

    Science.gov (United States)

    Garcia, GNA

    2007-01-01

    A rich narrative-style bibliography of accelerated learning (reviewing six articles published between 1995-2003). Articles reviewed include: (1) Accelerative learning and the Emerging Science of Wholeness (D. D. Beale); (2) Effective Teaching in Accelerated Learning Programs (D. Boyd); (3) A Critical Theory Perspective on Accelerated Learning (S.…

  2. Superconducting Linac and associated accelerator development at ...

    Indian Academy of Sciences (India)

    Abstract. There has been significant progress in the programme to develop a superconducting linear accelerator as a booster for the Pelletron accelerator at the Nuclear Science Centre. This paper presents the current status of the development in all the major components of the accelerator.

  3. Linear accelerator accelerating module to suppress back-acceleration of field-emitted particles

    Energy Technology Data Exchange (ETDEWEB)

    Benson, Stephen V.; Marhauser, Frank; Douglas, David R.; Ament, Lucas J. P.

    2017-12-05

    A method for the suppression of upstream-directed field emission in RF accelerators. The method is not restricted to a certain number of cavity cells, but requires similar operating field levels in all cavities to efficiently annihilate the once accumulated energy. Such a field balance is desirable to minimize dynamic RF losses, but not necessarily achievable in reality depending on individual cavity performance, such as early Q.sub.0-drop or quench field. The method enables a significant energy reduction for upstream-directed electrons within a relatively short distance. As a result of the suppression of upstream-directed field emission, electrons will impact surfaces at rather low energies leading to reduction of dark current and less issues with heating and damage of accelerator components as well as radiation levels including neutron generation and thus radio-activation.

  4. Learning models of intelligent agents

    Energy Technology Data Exchange (ETDEWEB)

    Carmel, D.; Markovitch, S. [Computer Science Dept., Haifa (Israel)

    1996-12-31

    Agents that operate in a multi-agent system need an efficient strategy to handle their encounters with other agents involved. Searching for an optimal interactive strategy is a hard problem because it depends mostly on the behavior of the others. In this work, interaction among agents is represented as a repeated two-player game, where the agents` objective is to look for a strategy that maximizes their expected sum of rewards in the game. We assume that agents` strategies can be modeled as finite automata. A model-based approach is presented as a possible method for learning an effective interactive strategy. First, we describe how an agent should find an optimal strategy against a given model. Second, we present an unsupervised algorithm that infers a model of the opponent`s automaton from its input/output behavior. A set of experiments that show the potential merit of the algorithm is reported as well.

  5. Flexible, secure agent development framework

    Science.gov (United States)

    Goldsmith,; Steven, Y [Rochester, MN

    2009-04-07

    While an agent generator is generating an intelligent agent, it can also evaluate the data processing platform on which it is executing, in order to assess a risk factor associated with operation of the agent generator on the data processing platform. The agent generator can retrieve from a location external to the data processing platform an open site that is configurable by the user, and load the open site into an agent substrate, thereby creating a development agent with code development capabilities. While an intelligent agent is executing a functional program on a data processing platform, it can also evaluate the data processing platform to assess a risk factor associated with performing the data processing function on the data processing platform.

  6. Signature energetic analysis of accelerate electron beam after first acceleration station by accelerating stand of Joint Institute for Nuclear Research

    Science.gov (United States)

    Sledneva, A. S.; Kobets, V. V.

    2017-06-01

    The linear electron accelerator based on the LINAC - 800 accelerator imported from the Netherland is created at Joint Institute for Nuclear Research in the framework of the project on creation of the Testbed with an electron beam of a linear accelerator with an energy up to 250 MV. Currently two accelerator stations with a 60 MV energy of a beam are put in operation and the work is to put the beam through accelerating section of the third accelerator station. The electron beam with an energy of 23 MeV is used for testing the crystals (BaF2, CsI (native), and LYSO) in order to explore the opportunity to use them in particle detectors in experiments: Muon g-2, Mu2e, Comet, whose preparation requires a detailed study of the detectors properties such as their irradiation by the accelerator beams.

  7. New antifungal agents.

    Science.gov (United States)

    Gupta, Aditya K; Tomas, Elizabeth

    2003-07-01

    Currently, use of standard antifungal therapies can be limited because of toxicity, low efficacy rates, and drug resistance. New formulations are being prepared to improve absorption and efficacy of some of these standard therapies. Various new antifungals have demonstrated therapeutic potential. These new agents may provide additional options for the treatment of superficial fungal infections and they may help to overcome the limitations of current treatments. Liposomal formulations of AmB have a broad spectrum of activity against invasive fungi, such as Candida spp., C. neoformans, and Aspergillus spp., but not dermatophyte fungi. The liposomal AmB is associated with significantly less toxicity and good rates of efficacy, which compare or exceed that of standard AmB. These factors may provide enough of an advantage to patients to overcome the increased costs of these formulations. Three new azole drugs have been developed, and may be of use in both systemic and superficial fungal infections. Voriconazole, ravuconazole, and posaconazole are triazoles, with broad-spectrum activity. Voriconazole has a high bioavailability, and has been used with success in immunocompromised patients with invasive fungal infections. Ravuconazole has shown efficacy in candidiasis in immunocompromised patients, and onychomycosis in healthy patients. Preliminary in vivo studies with posaconazole indicated potential use in a variety of invasive fungal infections including oropharyngeal candidiasis. Echinocandins and pneumocandins are a new class of antifungals, which act as fungal cell wall beta-(1,3)-D-glucan synthase enzyme complex inhibitors. Caspofungin (MK-0991) is the first of the echinocandins to receive Food and Drug Administration approval for patients with invasive aspergillosis not responding or intolerant to other antifungal therapies, and has been effective in patients with oropharyngeal and esophageal candidiasis. Standardization of MIC value determination has improved the

  8. their use as Accelerator in Curing Process of Rubber Compounds

    Directory of Open Access Journals (Sweden)

    S. taghvaee

    2007-06-01

    Full Text Available In some special cases, rubber compounds with high amounts of unsaturated elastomer are recommended with organic sulfur donors instead of mineral sulfurs. In this condition, activated sulfur is produced in situ and curingprocess is facilitated without accelerators. Organic sulfur donor compounds have low thermal stability and in the vulcanization temperature produce free and activated sulfurs. The advantages of these compounds are:1. High effectiveness of curing agent in low quantities in rubber compounds manufacturing.2. Producing activated sulfurs in controlled condition and avoiding the over curing of rubber compounds.In this report the novel synthesis of some derivatives of diamino-disulfides which can be applied as sulfur donors in vulcanization of special rubber compounds is introduced. The key process is reaction of sulfurmonochloride with amines in petroleum ether as solvent in low temperature. Dithio-dimorpholine(DTDM, dithio-dipipyridyl (DTDP, dithio-bis dibutylamine (DTBDB and dithio-bisdiisopropyl amine (DTBDI were prepared according to this method. All products thus obtained were characterized by 1H and 13C-NMR spectroscopies. The effects of accelerating and sulfur donoring of all prepared agents were detected in rubber compounds with natural and synthetic rubber bases. All physical, chemical, reological and mechanical properties of rubber compounds based on prepared sulfur donors were characterized.

  9. Mushrooms as therapeutic agents

    Directory of Open Access Journals (Sweden)

    Sushila Rathee

    2012-04-01

    Full Text Available Mushrooms have been known for their nutritional and culinary values and used as medicines and tonics by humans for ages. In modern terms, they can be considered as functional foods which can provide health benefits beyond the traditional nutrients. There are monographs that cover the medicinal and healing properties of some individual traditional mushrooms. There has been a recent upsurge of interest in mushrooms not only as a health food which is rich in protein but also as a source of biologically active compounds of medicinal value which include complementary medicine/dietary supplements for anticancer, antiviral, hepatoprotective, immunopotentiating and hypocholesterolemic agents. However the mechanisms of the various health benefits of mushrooms to humans still require intensive investigation, especially given the emergence of new evidence of their health benefits. In the present paper the medicinal potential of mushrooms is being discussed.

  10. [Chemotherapeutic agents under study].

    Science.gov (United States)

    Kawahara, S

    1998-12-01

    The development of new drugs with strong antituberculous activity and fewer side effects which are not cross-resistant to conventional antituberculosis drugs is urgently desired now. The chemotherapeutic agents under study which are considered a candidate for a new antituberculosis drug are listed below. 1) Rifamycin derivatives: rifabutin, rifapentin, KRM-1648, FCE-22250, 22807, CGP-7040, 27557, 29035, 29861, P-DEA, SPA-S-565, R-76-1. 2) New quinolones: ofloxacin, ciprofloxacin, levofloxacin, sparfloxacin, gatifloxacin, CS-940, Du-6859a. 3) Phenazines: clofazimine, B746, B4101, B4154, B4157. 4) Pyrazinamide derivatives: N-hydroxy pyrazinamide, N-hydroxy pyrazinamide-4-oxide. 5) Nitroimidazole derivatives: metronidazole et al.

  11. Health physics practices at research accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, R.H.

    1976-02-01

    A review is given of the uses of particle accelerators in health physics, the text being a short course given at the Health Physics Society Ninth Midyear Topical Symposium in February, 1976. Topics discussed include: (1) the radiation environment of high energy accelerators; (2) dosimetry at research accelerators; (3) shielding; (4) induced activity; (5) environmental impact of high energy accelerators; (6) population dose equivalent calculation; and (7) the application of the ''as low as practicable concept'' at accelerators. (PMA)

  12. High-energy cosmic-ray acceleration

    CERN Document Server

    Bustamante, M; de Paula, W; Duarte Chavez, J A; Gago, A M; Hakobyan, H; Jez, P; Monroy Montañez, J A; Ortiz Velasquez, A; Padilla Cabal, F; Pino Rozas, M; Rodriguez Patarroyo, D J; Romeo, G L; Saldaña-Salazar , U J; Velasquez, M; von Steinkirch, M

    2010-01-01

    We briefly review the basics of ultrahigh-energy cosmic-ray acceleration. The Hillas criterion is introduced as a geometrical criterion that must be fulfilled by potential acceleration sites, and energy losses are taken into account in order to obtain a more realistic scenario. The different available acceleration mechanisms are presented, with special emphasis on Fermi shock acceleration and its prediction of a power-law cosmic-ray energy spectrum. We conclude that first-order Fermi acceleration, though not entirely satisfactory, is the most promising mechanism for explaining the ultra-high-energy cosmic-ray flux.

  13. Accelerator Technology Division progress report, FY 1992

    Energy Technology Data Exchange (ETDEWEB)

    Schriber, S.O.; Hardekopf, R.A.; Heighway, E.A.

    1993-07-01

    This report briefly discusses the following topics: The Ground Test Accelerator Program; Defense Free-Electron Lasers; AXY Programs; A Next Generation High-Power Neutron-Scattering Facility; JAERI OMEGA Project and Intense Neutron Sources for Materials Testing; Advanced Free-Electron Laser Initiative; Superconducting Supercollider; The High-Power Microwave (HPM) Program; Neutral Particle Beam (NPB) Power Systems Highlights; Industrial Partnering; Accelerator Physics and Special Projects; Magnetic Optics and Beam Diagnostics; Accelerator Design and Engineering; Radio-Frequency Technology; Accelerator Theory and Free-Electron Laser Technology; Accelerator Controls and Automation; Very High-Power Microwave Sources and Effects; and GTA Installation, Commissioning, and Operations.

  14. ACFA and IPAC announce accelerator prizes

    CERN Multimedia

    CERN Bulletin

    2010-01-01

    Steve Myers, CERN's Director for Accelerators and Technology. The Asian Committee for Future Accelerators (ACFA) has joined forces with the first International Particle Accelerator Conference, IPAC’10, to award prizes for outstanding work in the field of accelerators. The conference replaces the regional conferences of the Americas, Europe and Asia and will be hosted by the three regions on a rotational basis (see CERN Courier). The ACFA/IPAC’10 Prizes Selection Committee, chaired by Won Namkung of Pohang Accelerator Laboratory, decided on the prizes and the names of the winners at a meeting on 20 January. The awards will be made during IPAC’10, which will be held in Kyoto on 23-28 May. Jie Wei. (Courtesy Tsinghua University.) Steve Myers, Director for Accelerators and Technology at CERN, receives an Achievement Prize for Outstanding Work in the Accelerator Field with no Age Limit “for his numerous outstanding contributions to the design, construction, commissio...

  15. Multi-beam linear accelerator EVT

    Energy Technology Data Exchange (ETDEWEB)

    Teryaev, Vladimir E., E-mail: vladimir_teryaev@mail.ru [Omega-P, Inc., New Haven, CT 06510 (United States); Kazakov, Sergey Yu. [Fermilab, Batavia, IL 60510 (United States); Hirshfield, Jay L. [Omega-P, Inc., New Haven, CT 06510 (United States); Yale University, New Haven, CT 06511 (United States)

    2016-09-01

    A novel electron multi-beam accelerator is presented. The accelerator, short-named EVT (Electron Voltage Transformer) belongs to the class of two-beam accelerators. It combines an RF generator and essentially an accelerator within the same vacuum envelope. Drive beam-lets and an accelerated beam are modulated in RF modulators and then bunches pass into an accelerating structure, comprising uncoupled with each other and inductive tuned cavities, where the energy transfer from the drive beams to the accelerated beam occurs. A phasing of bunches is solved by choice correspond distances between gaps of the adjacent cavities. Preliminary results of numerical simulations and the initial specification of EVT operating in S-band, with a 60 kV gun and generating a 2.7 A, 1.1 MV beam at its output is presented. A relatively high efficiency of 67% and high design average power suggest that EVT can find its use in industrial applications.

  16. Plasma Channel Guided Laser Wakefield Accelerator

    CERN Document Server

    Geddes, C G

    2005-01-01

    High quality electron beams (several 109 electrons above 80 MeV energy with percent energy spread and low divergence) have been produced for the first time in a compact, high gradient, all-optical laser accelerator by extending the interaction distance using a pre-formed plasma density channel to guide the drive laser pulse. Laser-driven accelerators, in which particles are accelerated by the electric field of a plasma wave (wake) driven by the radiation pressure of an intense laser, have over the past decade demonstrated accelerating fields thousands of times greater than those achievable in conventional radio-frequency accelerators. This has spurred interest in them as compact next- generation sources of energetic electrons and radiation. To date, however, acceleration distances have been severely limited by the lack of a controllable method for extending the propagation distance of the focused laser pulse. The ensuing short acceleration distance resulted in low-energy beams with 100 percent electron energy...

  17. FERMILAB ACCELERATOR R&D PROGRAM TOWARDS INTENSITY FRONTIER ACCELERATORS : STATUS AND PROGRESS

    Energy Technology Data Exchange (ETDEWEB)

    Shiltsev, Vladimir [Fermilab

    2016-11-15

    The 2014 P5 report indicated the accelerator-based neutrino and rare decay physics research as a centrepiece of the US domestic HEP program at Fermilab. Operation, upgrade and development of the accelerators for the near- term and longer-term particle physics program at the Intensity Frontier face formidable challenges. Here we discuss key elements of the accelerator physics and technology R&D program toward future multi-MW proton accelerators and present its status and progress. INTENSITY FRONTIER ACCELERATORS

  18. Technical report on the accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Bex, L. [ed.

    1995-12-31

    GANIL operation and the technical studies performed in 1994 are described. The milestones for 1994 are: SISSI (Source d`Ions Secondaires a Supraconducteurs Intense) has been in operation and used for secondary beam production with four different primary beams. The 100 kV platform for beam injection in the CO1 has been in operation for production of metallic beams which demand is increasing. Finally the SPIRAL project (Systeme de Production d`Ions Radioactifs Acceleres en Ligne) is in progress. In late 1994 the civil work has started in view of the installation of the machine in the north part of the GANIL machine building. (K.A.). 48 refs.

  19. Accelerators for charged particle therapy

    Science.gov (United States)

    Flanz, Jacob

    2015-06-01

    History has shown that energetic particles can be useful for medical applications. From the time, in 1895 when Roentgen discovered X-rays, and in 1913 when Coolidge developed the vacuum X-ray tube, energetic particles have been an important tool for medicine. Development of the appropriate tool for effective and safe radiotherapy requires an in-depth understanding of the application and constraints. Various solutions are possible and choices must be analyzed on the basis of the suitability for meeting the requirements. Some of the requirements of charged particle therapy are summarized and various accelerator options are described and discussed.

  20. AESS: Accelerated Exact Stochastic Simulation

    Science.gov (United States)

    Jenkins, David D.; Peterson, Gregory D.

    2011-12-01

    The Stochastic Simulation Algorithm (SSA) developed by Gillespie provides a powerful mechanism for exploring the behavior of chemical systems with small species populations or with important noise contributions. Gene circuit simulations for systems biology commonly employ the SSA method, as do ecological applications. This algorithm tends to be computationally expensive, so researchers seek an efficient implementation of SSA. In this program package, the Accelerated Exact Stochastic Simulation Algorithm (AESS) contains optimized implementations of Gillespie's SSA that improve the performance of individual simulation runs or ensembles of simulations used for sweeping parameters or to provide statistically significant results. Program summaryProgram title: AESS Catalogue identifier: AEJW_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEJW_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: University of Tennessee copyright agreement No. of lines in distributed program, including test data, etc.: 10 861 No. of bytes in distributed program, including test data, etc.: 394 631 Distribution format: tar.gz Programming language: C for processors, CUDA for NVIDIA GPUs Computer: Developed and tested on various x86 computers and NVIDIA C1060 Tesla and GTX 480 Fermi GPUs. The system targets x86 workstations, optionally with multicore processors or NVIDIA GPUs as accelerators. Operating system: Tested under Ubuntu Linux OS and CentOS 5.5 Linux OS Classification: 3, 16.12 Nature of problem: Simulation of chemical systems, particularly with low species populations, can be accurately performed using Gillespie's method of stochastic simulation. Numerous variations on the original stochastic simulation algorithm have been developed, including approaches that produce results with statistics that exactly match the chemical master equation (CME) as well as other approaches that approximate the CME. Solution

  1. Falsifying Paradigms for Cosmic Acceleration

    Energy Technology Data Exchange (ETDEWEB)

    Huterer, Dragan [Department of Physics, University of Michigan, 450 Church St, Ann Arbor, MI 48109-1040 (United States)

    2009-10-15

    Consistency relations between growth of structure and expansion history observables exist for any physical explanation of cosmic acceleration. We perform MCMC likelihood exploration of these relations, using future SNAP supernova and Planck CMB data to derive the expected variation in the growth and distance functions and the Hubble parameter under different classes of models for dark energy - a cosmological constant, scalar field quintessence, or a general smooth component, allowing at the same time for nonzero curvature and early dark energy. For each class we identify tight redshift-dependent predictions.

  2. Collective dynamics of accelerated atoms

    Science.gov (United States)

    Richter, Benedikt; Terças, Hugo; Omar, Yasser; de Vega, Inés

    2017-11-01

    We study the collective dynamics of accelerated atoms interacting with a massless field via an Unruh-deWitt-type interaction. We first derive a general Hamiltonian describing such a system and then, employing a Markovian master equation, we study the corresponding collective dynamics. In particular, we observe that the emergence of entanglement between two-level atoms is linked to the building up of coherences between them and to superradiant emission. In addition, we show that the derived Hamiltonian can be experimentally implemented by employing impurities in Bose-Einstein condensates.

  3. Odor Classification using Agent Technology

    Directory of Open Access Journals (Sweden)

    Sigeru OMATU

    2014-03-01

    Full Text Available In order to measure and classify odors, Quartz Crystal Microbalance (QCM can be used. In the present study, seven QCM sensors and three different odors are used. The system has been developed as a virtual organization of agents using an agent platform called PANGEA (Platform for Automatic coNstruction of orGanizations of intElligent Agents. This is a platform for developing open multi-agent systems, specifically those including organizational aspects. The main reason for the use of agents is the scalability of the platform, i.e. the way in which it models the services. The system models functionalities as services inside the agents, or as Service Oriented Approach (SOA architecture compliant services using Web Services. This way the adaptation of the odor classification systems with new algorithms, tools and classification techniques is allowed.

  4. Accelerated ageing of molybdenum oxide

    Science.gov (United States)

    Jorge, Marina; Cooil, Simon; Edmonds, Mark T.; Thomsen, Lars; Nematollahi, Mohammadreza; Mazzola, Federico; Wells, Justin W.

    2017-11-01

    The stability and lifetime of materials proposed for photovoltaic applications are important parameters, because such devices should offer long-term reliable performance whilst operating in a harsh environment. In this work, we present a powerful approach to accelerate and study the degradation mechanisms of molybdenum oxide, a material which has shown promise for next generation photovoltaics, and for enhanced hole extraction in organic photovoltaics. We use UV and soft x-rays to drive accelerated ageing, boosting the ageing time by a factor of up to 1000. Using this method, we find that molybdenum oxide does not offer reliable performance in environments in which heating or ionising radiation are present, because of its propensity to reduce, thus strongly modifying its electronic properties. We estimate that  ≈100 d of unfiltered sunlight exposure would be sufficient to reduce this material into metallic MoO2. We also show that a very similar degradation can be driven by thermally, and that in both cases, the creation of oxygen vacancies is responsible. A lack of robustness to harsh operating conditions (i.e. UV and/or heat) brings the suitability of unprotected molybdenum oxide in photovoltaic applications into question.

  5. Particle Accelerators for PET radionuclides

    DEFF Research Database (Denmark)

    Jensen, Mikael

    2012-01-01

    The requirements set for particle accelerators for production of radioactive isotopes for PET can easily be derived from first principles. The simple general need is for proton beams with energy in the region 10–20 MeV and current 20–100 microAmps. This is most reliably and cost-effectively achie......The requirements set for particle accelerators for production of radioactive isotopes for PET can easily be derived from first principles. The simple general need is for proton beams with energy in the region 10–20 MeV and current 20–100 microAmps. This is most reliably and cost...... different manufacturers will be discussed the light of what is actually needed for a given PET site operation. Alternatives to the conventional cyclotron have been proposed and tested but have at present very limited use. These alternatives will be discussed, as well as the future possibilities of supplying...... point of demand tracer production with very small cyclotrons of energy well below 10 MeV. The authors best advice at present for new PET sites is to negotiate for conventional cyclotron solutions from experienced manufacturers. It is the combined performance of cyclotron and target in terms of available...

  6. heavy ion acceleration at shocks

    Science.gov (United States)

    Shevchenko, V. I.; Galinsky, V.

    2009-12-01

    The theoretical study of alpha particle acceleration at a quasi-parallel shock due to interaction with Alfven waves self-consistently excited in both upstream and downstream regions was conducted using a scale-separation model [1]. The model uses conservation laws and resonance conditions to find where waves will be generated or dumped and hence particles will be pitch--angle scattered as well as the change of the wave energy due to instability or damping. It includes in consideration the total distribution function (the bulk plasma and high energy tail), so no any assumptions (e.g. seed populations, or some ad-hoc escape rate of accelerated particles) are required. In previous studies heavy ions were treated as perfect test particles, they only experienced the Alfven turbulence excited by protons and didn’t contribute to turbulence generation. In contrast to this approach, we consider the ion scattering on hydromagnetic turbulence generated by both protons and ions themselves. It is important for alpha particles with their relatively large mass-loading parameter that defines efficiency of the wave excitation by alpha particles. The energy spectra of alpha particles is found and compared with those obtained in test particle approximation. [1] Galinsky, V.L., and V.I. Shevchenko, Astrophys. J., 669, L109, 2007.

  7. Winter therapy for the accelerators

    CERN Multimedia

    Corinne Pralavorio

    2016-01-01

    Hundreds of people are hard at work during the year-end technical stop as all the accelerators are undergoing maintenance, renovation and upgrade operations in parallel.   The new beam absorber on its way to Point 2 before being lowered into the LHC tunnel for installation. The accelerator teams didn’t waste any time before starting their annual winter rejuvenation programme over the winter. At the end of November, as the LHC ion run was beginning, work got under way on the PS Booster, where operation had already stopped. On 14 December, once the whole complex had been shut down, the technical teams turned their attention to the other injectors and the LHC. The year-end technical stop (YETS) provides an opportunity to carry out maintenance work on equipment and repair any damage as well as to upgrade the machines for the upcoming runs. Numerous work projects are carried out simultaneously, so good coordination is crucial. Marzia Bernardini's team in the Enginee...

  8. GPU Accelerated Vector Median Filter

    Science.gov (United States)

    Aras, Rifat; Shen, Yuzhong

    2011-01-01

    Noise reduction is an important step for most image processing tasks. For three channel color images, a widely used technique is vector median filter in which color values of pixels are treated as 3-component vectors. Vector median filters are computationally expensive; for a window size of n x n, each of the n(sup 2) vectors has to be compared with other n(sup 2) - 1 vectors in distances. General purpose computation on graphics processing units (GPUs) is the paradigm of utilizing high-performance many-core GPU architectures for computation tasks that are normally handled by CPUs. In this work. NVIDIA's Compute Unified Device Architecture (CUDA) paradigm is used to accelerate vector median filtering. which has to the best of our knowledge never been done before. The performance of GPU accelerated vector median filter is compared to that of the CPU and MPI-based versions for different image and window sizes, Initial findings of the study showed 100x improvement of performance of vector median filter implementation on GPUs over CPU implementations and further speed-up is expected after more extensive optimizations of the GPU algorithm .

  9. High Temperature Superconductor Accelerator Magnets

    CERN Document Server

    AUTHOR|(CDS)2079328; de Rijk, Gijs; Dhalle, Marc

    2016-11-10

    For future particle accelerators bending dipoles are considered with magnetic fields exceeding $20T$. This can only be achieved using high temperature superconductors (HTS). These exhibit different properties from classical low temperature superconductors and still require significant research and development before they can be applied in a practical accelerator magnet. In order to study HTS in detail, a five tesla demonstrator magnet named Feather-M2 is designed and constructed. The magnet is based on ReBCO coated conductor, which is assembled into a $10kA$ class Roebel cable. A new and optimized Aligned Block layout is used, which takes advantage of the anisotropy of the conductor. This is achieved by providing local alignment of the Roebel cable in the coil windings with the magnetic field lines. A new Network Model capable of analyzing transient electro-magnetic and thermal phenomena in coated conductor cables and coils is developed. This model is necessary to solve critical issues in coated conductor ac...

  10. Testing general relativity on accelerators

    Directory of Open Access Journals (Sweden)

    Tigran Kalaydzhyan

    2015-11-01

    Full Text Available Within the general theory of relativity, the curvature of spacetime is related to the energy and momentum of the present matter and radiation. One of the more specific predictions of general relativity is the deflection of light and particle trajectories in the gravitational field of massive objects. Bending angles for electromagnetic waves and light in particular were measured with a high precision. However, the effect of gravity on relativistic massive particles was never studied experimentally. Here we propose and analyze experiments devoted to that purpose. We demonstrate a high sensitivity of the laser Compton scattering at high energy accelerators to the effects of gravity. The main observable – maximal energy of the scattered photons – would experience a significant shift in the ambient gravitational field even for otherwise negligible violation of the equivalence principle. We confirm predictions of general relativity for ultrarelativistic electrons of energy of tens of GeV at a current level of resolution and expect our work to be a starting point of further high-precision studies on current and future accelerators, such as PETRA, European XFEL and ILC.

  11. Anticancer agents from medicinal plants

    Directory of Open Access Journals (Sweden)

    Mohammad Shoeb

    2006-06-01

    Full Text Available Cancer is a major public health burden in both developed and developing countries. Plant derived agents are being used for the treatment of cancer. Several anticancer agents including taxol, vinblastine, vincristine, the camptothecin derivatives, topotecan and irinotecan, and etoposide derived from epipodophyllotoxin are in clinical use all over the world. A number of promising agents such as flavopiridol, roscovitine, combretastatin A-4, betulinic acid and silvestrol are in clinical or preclinical development.

  12. Anticancer agents from medicinal plants

    Directory of Open Access Journals (Sweden)

    Mohammad Shoeb

    2006-12-01

    Full Text Available Cancer is a major public health burden in both developed and developing countries. Plant derived agents are being used for the treatment of cancer. Several anticancer agents including taxol, vinblas-tine, vincristine, the camptothecin derivatives, topotecan and irinotecan, and etoposide derived from epipodophyllotoxin are in clinical use all over the world. A number of promising agents such as flavopiridol, roscovitine, combretastatin A-4, betulinic acid and silvestrol are in clinical or preclinical development.

  13. Firefighting Agent Research, Phase I

    National Research Council Canada - National Science Library

    Dierdorf, Douglas S; Enlow, Mark A; Stern, Seymour; Carr, Virgil J

    2007-01-01

    .... Such physical characteristics as equilibrium surface tension, dynamic interfacial tension, and surface pressure have been examined in order to determine agent/surfactant behavior during the extinguishment process...

  14. Business Intelligence using Software Agents

    Directory of Open Access Journals (Sweden)

    Ana-Ramona BOLOGA

    2011-12-01

    Full Text Available This paper presents some ideas about business intelligence today and the importance of developing real time business solutions. The authors make an exploration of links between business intelligence and artificial intelligence and focuses specifically on the implementation of software agents-based systems in business intelligence. There are briefly presented some of the few solutions proposed so far that use software agents properties for the benefit of business intelligence. The authors then propose some basic ideas for developing real-time agent-based software system for business intelligence in supply chain management, using Case Base Reasoning Agents.

  15. Synergia CUDA: GPU-accelerated accelerator modeling package

    Science.gov (United States)

    Lu, Q.; Amundson, J.

    2014-06-01

    Synergia is a parallel, 3-dimensional space-charge particle-in-cell accelerator modeling code. We present our work porting the purely MPI-based version of the code to a hybrid of CPU and GPU computing kernels. The hybrid code uses the CUDA platform in the same framework as the pure MPI solution. We have implemented a lock-free collaborative charge-deposition algorithm for the GPU, as well as other optimizations, including local communication avoidance for GPUs, a customized FFT, and fine-tuned memory access patterns. On a small GPU cluster (up to 4 Tesla C1070 GPUs), our benchmarks exhibit both superior peak performance and better scaling than a CPU cluster with 16 nodes and 128 cores. We also compare the code performance on different GPU architectures, including C1070 Tesla and K20 Kepler.

  16. Agent Mediated Electronic Commerce: Designing Trading Agents and Mechanisms

    NARCIS (Netherlands)

    J.A. La Poutré (Han); N.M. Sadeh; S. Janson

    2006-01-01

    htmlabstractThis book constitutes the thoroughly refereed post-proceedings of the 7th International Workshop on Agent-Mediated Electronic Commerce, AMEC VII 2005, held in Utrecht, Netherlands in July 2005, as part of AAMAS 2005, and the third Workshop on Trading Agent Design and Analysis, TADA 2005,

  17. Incorporating BDI Agents into Human-Agent Decision Making Research

    Science.gov (United States)

    Kamphorst, Bart; van Wissen, Arlette; Dignum, Virginia

    Artificial agents, people, institutes and societies all have the ability to make decisions. Decision making as a research area therefore involves a broad spectrum of sciences, ranging from Artificial Intelligence to economics to psychology. The Colored Trails (CT) framework is designed to aid researchers in all fields in examining decision making processes. It is developed both to study interaction between multiple actors (humans or software agents) in a dynamic environment, and to study and model the decision making of these actors. However, agents in the current implementation of CT lack the explanatory power to help understand the reasoning processes involved in decision making. The BDI paradigm that has been proposed in the agent research area to describe rational agents, enables the specification of agents that reason in abstract concepts such as beliefs, goals, plans and events. In this paper, we present CTAPL: an extension to CT that allows BDI software agents that are written in the practical agent programming language 2APL to reason about and interact with a CT environment.

  18. Deliberate evolution in multi-agent systems

    NARCIS (Netherlands)

    F.M.T. Brazier; C.M. Jonker (Catholijn); J. Treur; N.J.E. Wijngaards

    1998-01-01

    textabstract This paper presents an architecture for an agent capable of deliberation about the creation of new agents, and of actually creating a new agent in the multi-agent system, on the basis of this deliberation. After its creation the new agent participates fully in the running multi-agent

  19. CAS course on Plasma Wake Acceleration

    CERN Multimedia

    CERN Accelerator School

    2015-01-01

    The CERN Accelerator School (CAS) recently organised a specialised course on Plasma Wake Acceleration, held at CERN, Geneva, Switzerland, from 23 to 29 November 2014.    Following a number of introductory lectures on laser and plasma physics, as well as an overview of conventional accelerators and their limitations, the course covered a large number of aspects of plasma wake acceleration schemes: the creation of plasma by high power lasers or particle beams, a description of the plasma creation process through simulations and the characteristics of the accelerated particle beams, including results of the latest achievements. Lectures on beam diagnostics, the applications of plasma accelerated beams, and topical seminars completed the programme.  The course was very successful, with 109 students of 26 nationalities attending; most participants coming from European counties, but also from the US, Israel, India, South Korea, Russia and Ukraine. Feedback from the participants was...

  20. Stephen Myers - More collaboration for accelerators

    CERN Multimedia

    2009-01-01

    Stephen Myers has been appointed Director of Accelerators and Technology. His highest priority is to get the LHC running this year, but beyond that he also has the difficult task of balancing resources between non-LHC physics, new projects and consolidation of the existing accelerators. Stephen Myers, previous head of the Accelerator and Beams (AB) Department, will now oversee all the accelerator and technology activities at CERN, including the Beams, Technology and Engineering departments, in the re-established position of Director of Accelerators and Technology. "There are several good reasons to have a single person responsible for the CERN accelerators and technology," said Myers. "Most importantly, this will allow closer collaboration between the three departments and provide the structure for possible redeployment of resources. There will, of course, be regular meetings between the heads of department and myself, and if proble...

  1. An Accelerator control middle layer using Matlab

    CERN Document Server

    Portmann, G J; Terebilo, Andrei

    2005-01-01

    Matlab is a matrix manipulation language originally developed to be a convenient language for using the LINPACK and EISPACK libraries. What makes Matlab so appealing for accelerator physics is the combination of a matrix oriented programming language, an active workspace for system variables, powerful graphics capability, built-in math libraries, and platform independence. A number of software toolboxes for accelerators have been written in Matlab – the Accelerator Toolbox (AT) for machine simulations, LOCO for accelerator calibration, Matlab Channel Access Toolbox (MCA) for EPICS connections, and the Middle Layer. This paper will describe the MiddleLayer software toolbox that resides between the high-level control applications and the low-level accelerator control system. This software was a collaborative effort between ALS and Spear but was written to easily port. Five accelerators presently use this software – Spear, ALS, CLS, and the X-ray and VUV rings at Brookhaven. The Middle Layer fu...

  2. Electron Acceleration in Supernovae and Millimeter Perspectives

    Directory of Open Access Journals (Sweden)

    Keiichi Maeda

    2014-12-01

    Full Text Available Supernovae launch a strong shock wave by the interaction of the expanding ejecta and surrounding circumstellar matter (CSM. At the shock, electrons are accelerated to relativistic speed, creating observed synchrotron emissions in radio wavelengths. In this paper, I suggest that SNe (i.e., < 1 year since the explosion provide a unique site to study the electron acceleration mechanism. I argue that the eciency of the acceleration at the young SN shock is much lower than conventionally assumed, and that the electrons emitting in the cm wavelengths are not fully in the Diffusive Shock Acceleration (DSA regime. Thus radio emissions from young SNe record information on the yet-unresolved 'injection' mechanism. I also present perspectives of millimeter (mm observations of SNe - this will provide opportunities to uniquely determine the shock physics and the acceleration efficiency, to test the non-linear DSA mechanism and provide a characteristic electron energy scale with which the DSA start dominating the electron acceleration.

  3. Extinction events can accelerate evolution.

    Science.gov (United States)

    Lehman, Joel; Miikkulainen, Risto

    2015-01-01

    Extinction events impact the trajectory of biological evolution significantly. They are often viewed as upheavals to the evolutionary process. In contrast, this paper supports the hypothesis that although they are unpredictably destructive, extinction events may in the long term accelerate evolution by increasing evolvability. In particular, if extinction events extinguish indiscriminately many ways of life, indirectly they may select for the ability to expand rapidly through vacated niches. Lineages with such an ability are more likely to persist through multiple extinctions. Lending computational support for this hypothesis, this paper shows how increased evolvability will result from simulated extinction events in two computational models of evolved behavior. The conclusion is that although they are destructive in the short term, extinction events may make evolution more prolific in the long term.

  4. Building bridges … and accelerators

    CERN Multimedia

    2009-01-01

    Lyn Evans, the LHC project leader, was awarded an honorary doctorate from the University of Geneva (UNIGE) to celebrate his role not just in building accelerators, but also in building bridges between nations. He was one of four notables honoured at the event on Friday 5 June, coinciding with the University’s 450th Anniversary. Lyn Evans arriving at the ceremony with Archbishop Desmond Tutu. "It was a big surprise when I found out I’d been nominated," recounts Evans, "but it was an even bigger surprise to find out with whom I’d been nominated". At the ceremony Evans was awarded the honorary doctorate along with three others: Archbishop Desmond Tutu, who was acclaimed for his fight against apartheid in South Africa, Mary Robinson, first woman president of Ireland and former United Nations’ high commissioner of human rights, and Pascal Lamy, Director-General of the World Trade Organization. The award ceremony, known as the �...

  5. Accelerated Characterization of Polymer Properties

    Energy Technology Data Exchange (ETDEWEB)

    R. Wroczynski; l. Brewer; D. Buckley; M. Burrell; R. Potyrailo

    2003-07-30

    This report describes the efforts to develop a suite of microanalysis techniques that can rapidly measure a variety of polymer properties of industrial importance, including thermal, photo-oxidative, and color stability; as well as ductility, viscosity, and mechanical and antistatic properties. Additional goals of the project were to direct the development of these techniques toward simultaneous measurements of multiple polymer samples of small size in real time using non-destructive and/or parallel or rapid sequential measurements, to develop microcompounding techniques for preparing polymers with additives, and to demonstrate that samples prepared in the microcompounder could be analyzed directly or used in rapid off-line measurements. These enabling technologies are the crucial precursors to the development of high-throughput screening (HTS) methodologies for the polymer additives industry whereby the rate of development of new additives and polymer formulations can be greatly accelerated.

  6. Collaborative Workspaces to Accelerate Discovery

    Science.gov (United States)

    Meade, Bernard; Fluke, Christopher; Cooke, Jeff; Andreoni, Igor; Pritchard, Tyler; Curtin, Christopher; Bernard, Stephanie R.; Asher, Albany; Mack, Katherine J.; Murphy, Michael T.; Vohl, Dany; Codoreanu, Alex; Kotuš, Srđan M.; Rumokoy, Fanuel; Horst, Chuck; Reynolds, Tristan

    2017-05-01

    By applying a display ecology to the Deeper, Wider, Faster proactive, simultaneous telescope observing campaign, we have shown a dramatic reduction in the time taken to inspect DECam CCD images for potential transient candidates and to produce time-critical triggers to standby telescopes. We also show how facilitating rapid corroboration of potential candidates and the exclusion of non-candidates improves the accuracy of detection; and establish that a practical and enjoyable workspace can improve the experience of an otherwise taxing task for astronomers. We provide a critical road test of two advanced displays in a research context-a rare opportunity to demonstrate how they can be used rather than simply discuss how they might be used to accelerate discovery.

  7. 28th Linear Accelerator Conference

    CERN Document Server

    Facco, Alberto; McCausey, Amy; Schaa, Volker R W

    2017-01-01

    The 28th Linear Accelerator Conference, LINAC 16, to take place at the Kellogg Hotel and Conference Center in East Lansing, Michigan, on 25-30 September 2016. This conference is the main bi-yearly gathering for the world-wide community of linac specialists. It provides a unique opportunity to hear about the latest advances of projects and developments concerning hadron and lepton linacs, and their applications. In the tradition of previous LINAC conferences, plenary sessions including invited speakers are scheduled every day. Poster sessions will be held on Monday, Tuesday and Thursday afternoons. There will also be two special events on Sunday, 25 September 2016, namely a student poster session and an evening reception for registrants and their companions at the Kellogg Hotel and Conference Center. Participants are also warmly invited to join an outing to Lake Michigan and the beautiful surroundings on Wednesday afternoon, and to visit the Facility for Rare Isotope Beams on Friday afternoon, after the formal...

  8. Players' agents worldwide: legal aspects

    NARCIS (Netherlands)

    Siekmann, R.C.R.; Parrish, R.; Branco Martins, R.; Soek, J.W.

    2007-01-01

    Publicly, at least, there appears to be a strong collective will within football to clean up the game, to make the work of players’ agents more transparent and to allow a greater share of the game’s profits to stay within the game. Privately, there seems to be unease that current agent regulation is

  9. Social Agents: the first generations

    NARCIS (Netherlands)

    Heylen, Dirk K.J.; Theune, Mariet; op den Akker, Hendrikus J.A.; Nijholt, Antinus; Pantic, Maja; Vinciarello, A.

    2009-01-01

    Embodied Conversational Agents can be viewed as spoken dialogue systems with a graphical representation of a human body. But the embodiment is not the only difference. Whereas Spoken Dialogue Systems are mostly focused on computing the linguistic dimensions of communication, conversational agents

  10. Modelling Reasoning and Acting Agents

    NARCIS (Netherlands)

    Dunin-Keplicz, B.M.; Treur, J.

    1995-01-01

    This paper addresses the issue of the use of formal modelling languages in multi-agent domains. As a main question we evaluate in what respect the formal modelling language DESIRE fulfills the requirements imposed by these domains. To get an answer we studied two examples of multi-agent tasks and

  11. 13 CFR 108.1620 - Functions of agents, including Central Registration Agent, Selling Agent and Fiscal Agent.

    Science.gov (United States)

    2010-01-01

    ... appoint a Fiscal Agent to: (i) Establish performance criteria for Poolers. (ii) Monitor and evaluate the... Assistance for NMVC Companies (Leverage) Funding Leverage by Use of Sba Guaranteed Trust Certificates (âtcsâ... Debenture, SBA may cause each NMVC Company to appoint a Selling Agent to perform functions that include, but...

  12. 13 CFR 107.1620 - Functions of agents, including Central Registration Agent, Selling Agent and Fiscal Agent.

    Science.gov (United States)

    2010-01-01

    ... Fiscal Agent to: (i) Establish performance criteria for Poolers. (ii) Monitor and evaluate the financial... Assistance SMALL BUSINESS ADMINISTRATION SMALL BUSINESS INVESTMENT COMPANIES SBA Financial Assistance for... Participating Securities. (iii) Monitor the performance of the Selling Agent, Poolers, CRA, and the Trustee. (iv...

  13. Accelerating cleanup: Paths to closure

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-06-01

    This report describes the status of Environmental Management`s (EM`s) cleanup program and a direction forward to complete achievement of the 2006 vision. Achieving the 2006 vision results in significant benefits related to accomplishing EM program objectives. As DOE sites accelerate cleanup activities, risks to public health, the environment, and worker safety and health are all reduced. Finding more efficient ways to conduct work can result in making compliance with applicable environmental requirements easier to achieve. Finally, as cleanup activities at sites are completed, the EM program can focus attention and resources on the small number of sites with more complex cleanup challenges. Chapter 1 describes the process by which this report has been developed and what it hopes to accomplish, its relationship to the EM decision-making process, and a general background of the EM mission and program. Chapter 2 describes how the site-by-site projections were constructed, and summarizes, for each of DOE`s 11 Operations/Field Offices, the projected costs and schedules for completing the cleanup mission. Chapter 3 presents summaries of the detailed cleanup projections from three of the 11 Operations/Field Offices: Rocky Flats (Colorado), Richland (Washington), and Savannah River (South Carolina). The remaining eight Operations/Field Office summaries are in Appendix E. Chapter 4 reviews the cost drivers, budgetary constraints, and performance enhancements underlying the detailed analysis of the 353 projects that comprise EM`s accelerated cleanup and closure effort. Chapter 5 describes a management system to support the EM program. Chapter 6 provides responses to the general comments received on the February draft of this document.

  14. Report on accelerated corrosion studies.

    Energy Technology Data Exchange (ETDEWEB)

    Mowry, Curtis Dale; Glass, Sarah Jill; Sorensen, Neil Robert

    2011-03-01

    Sandia National Laboratories (SNL) conducted accelerated atmospheric corrosion testing for the U.S. Consumer Product Safety Commission (CPSC) to help further the understanding of the development of corrosion products on conductor materials in household electrical components exposed to environmental conditions representative of homes constructed with problem drywall. The conditions of the accelerated testing were chosen to produce corrosion product growth that would be consistent with long-term exposure to environments containing humidity and parts per billion (ppb) levels of hydrogen sulfide (H{sub 2}S) that are thought to have been the source of corrosion in electrical components from affected homes. This report documents the test set-up, monitoring of electrical performance of powered electrical components during the exposure, and the materials characterization conducted on wires, screws, and contact plates from selected electrical components. No degradation in electrical performance (measured via voltage drop) was measured during the course of the 8-week exposure, which was approximately equivalent to 40 years of exposure in a light industrial environment. Analyses show that corrosion products consisting of various phases of copper sulfide, copper sulfate, and copper oxide are found on exposed surfaces of the conductor materials including wires, screws, and contact plates. The morphology and the thickness of the corrosion products showed a range of character. In some of the copper wires that were observed, corrosion product had flaked or spalled off the surface, exposing fresh metal to the reaction with the contaminant gasses; however, there was no significant change in the wire cross-sectional area.

  15. 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.

  16. Hybrid laser-plasma wakefield acceleration

    Science.gov (United States)

    Hidding, Bernhard; Heinemann, Thomas; Scherkl, Paul; Ullmann, Daniel; Beaton, Andrew

    2017-10-01

    Laser wakefield accelerators (LWFA) can produce electron bunches with characteristics which suggest they are highly suitable to be used as drivers for electron-beam driven plasma wakefield accelerators (PWFA). The presentation will report on recent experimental results and conceptual advanced which substantiate this idea. It looks as if hybrid LWFA-PWFA systems are highly promising systems to harness specific advantages of PWFA (no dephasing, long acceleration distances, wide potential for ionization injection schemes) realized these in truly compact systems.

  17. CUDA Accelerated LTL Model Checking -­ Revisited

    OpenAIRE

    Bauch, Petr; Ceska, Milan

    2011-01-01

    Recently, the massively parallel architecture has been used to significantly accelerate many computation demanding tasks. For example, in [Baier, Kateon, The MIT Press, 2009; Barnat, Brim, Ceska, ICPADS 2009] we have shown how CUDA technology can be employed to accelerate the process of Linear Temporal Logic (LTL) Model Checking. In this paper we redesign the One-Way-Catch-Them-Young (OWCTY) algorithm [Cerna, Pelanek, SPIN'03] in order to devise a new CUDA accelerated OWCTY algorithm that wil...

  18. Accelerated life models modeling and statistical analysis

    CERN Document Server

    Bagdonavicius, Vilijandas

    2001-01-01

    Failure Time DistributionsIntroductionParametric Classes of Failure Time DistributionsAccelerated Life ModelsIntroductionGeneralized Sedyakin's ModelAccelerated Failure Time ModelProportional Hazards ModelGeneralized Proportional Hazards ModelsGeneralized Additive and Additive-Multiplicative Hazards ModelsChanging Shape and Scale ModelsGeneralizationsModels Including Switch-Up and Cycling EffectsHeredity HypothesisSummaryAccelerated Degradation ModelsIntroductionDegradation ModelsModeling the Influence of Explanatory Varia

  19. Three-dimensional accelerating electromagnetic waves.

    Science.gov (United States)

    Bandres, Miguel A; Alonso, Miguel A; Kaminer, Ido; Segev, Mordechai

    2013-06-17

    We present a general theory of three-dimensional non-paraxial spatially-accelerating waves of the Maxwell equations. These waves constitute a two-dimensional structure exhibiting shape-invariant propagation along semicircular trajectories. We provide classification and characterization of possible shapes of such beams, expressed through the angular spectra of parabolic, oblate and prolate spheroidal fields. Our results facilitate the design of accelerating beams with novel structures, broadening scope and potential applications of accelerating beams.

  20. Kinematics of transition during human accelerated sprinting

    Directory of Open Access Journals (Sweden)

    Ryu Nagahara

    2014-07-01

    Full Text Available This study investigated kinematics of human accelerated sprinting through 50 m and examined whether there is transition and changes in acceleration strategies during the entire acceleration phase. Twelve male sprinters performed a 60-m sprint, during which step-to-step kinematics were captured using 60 infrared cameras. To detect the transition during the acceleration phase, the mean height of the whole-body centre of gravity (CG during the support phase was adopted as a measure. Detection methods found two transitions during the entire acceleration phase of maximal sprinting, and the acceleration phase could thus be divided into initial, middle, and final sections. Discriminable kinematic changes were found when the sprinters crossed the detected first transition—the foot contacting the ground in front of the CG, the knee-joint starting to flex during the support phase, terminating an increase in step frequency—and second transition—the termination of changes in body postures and the start of a slight decrease in the intensity of hip-joint movements, thus validating the employed methods. In each acceleration section, different contributions of lower-extremity segments to increase in the CG forward velocity—thigh and shank for the initial section, thigh, shank, and foot for the middle section, shank and foot for the final section—were verified, establishing different acceleration strategies during the entire acceleration phase. In conclusion, there are presumably two transitions during human maximal accelerated sprinting that divide the entire acceleration phase into three sections, and different acceleration strategies represented by the contributions of the segments for running speed are employed.

  1. Proton-driven Plasma Wakefield Acceleration

    CERN Multimedia

    CERN. Geneva

    2012-01-01

    The construction of ever larger and costlier accelerator facilities has a limited future, and new technologies will be needed to push the energy frontier. Plasma wakefield acceleration is a rapidly developing field and is a promising candidate technology for future high energy colliders. We focus on the recently proposed idea of proton-driven plasma wakefield acceleration and describe the current status and plans for this approach.

  2. Unifying physics of accelerators, lasers and plasma

    CERN Document Server

    Seryi, Andrei

    2015-01-01

    Unifying Physics of Accelerators, Lasers and Plasma introduces the physics of accelerators, lasers and plasma in tandem with the industrial methodology of inventiveness, a technique that teaches that similar problems and solutions appear again and again in seemingly dissimilar disciplines. This unique approach builds bridges and enhances connections between the three aforementioned areas of physics that are essential for developing the next generation of accelerators.

  3. Relational agents: A critical review

    DEFF Research Database (Denmark)

    Campbell, Robert H.; Grimshaw, Mark Nicholas; Green, Gill

    2009-01-01

    Relationships between people who meet in virtual worlds are common and these relationships can be long term, in some cases lasting a life-time. Although relationships formed in virtual worlds have invited a lot of recent interest, surprisingly little work has been done on developing computer agents...... and non-player characters that can actively participate in such relationships. The focus of this review is relational agents, agents that can build long term socioemotional relationships with users. In virtual worlds, such agents are just starting to emerge; they are more common in other environments...... but remain few and far between. This review critically assesses the progress of relational agent development and research since their inception in 2005, proposes new areas of research and considers the potential for their exploitation in virtual worlds....

  4. Advances of Accelerator Physics and Technologies

    CERN Document Server

    1993-01-01

    This volume, consisting of articles written by experts with international repute and long experience, reviews the state of the art of accelerator physics and technologies and the use of accelerators in research, industry and medicine. It covers a wide range of topics, from basic problems concerning the performance of circular and linear accelerators to technical issues and related fields. Also discussed are recent achievements that are of particular interest (such as RF quadrupole acceleration, ion sources and storage rings) and new technologies (such as superconductivity for magnets and RF ca

  5. Status of the ORNL 25URC accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Ziegler, N.F.; Milner, W.T.; Mills, G.D.; Meigs, M.J.; McPherson, R.L.; Juras, R.C.; Jones, C.M.; Hoglund, D.E.; Haynes, D.L.; Biggerstaff, J.A.

    1986-01-01

    The operation and maintenance of the ORNL 25URC accelerator is reported. The accelerator provided 4162 hours of beam for research in FY 1986. Hours of accelerator usage is shown for each month on a histogram. Accelerator tubes were replaced in two units. Compressed geometry tubes were installed as a test of the concept. A histogram of number of runs vs. terminal voltage is provided. The annular geometry surface ionization source was used exclusively. A new chopper-buncher system was installed in the injection line. (LEW)

  6. The financial accelerator effect: concept and challenges

    National Research Council Canada - National Science Library

    Bruno Coric

    2011-01-01

    .... We find that the financial accelerator effect, as it is known, provides a consistent, first principle based, theoretical framework for the analysis of the relationship between financial markets...

  7. New Trends in Induction Accelerator Technology

    Energy Technology Data Exchange (ETDEWEB)

    Caporaso, G J

    2002-12-05

    Recent advances in solid-state modulators now permit the design of a new class of high current accelerators. These new accelerators will be able to operate in burst mode at frequencies of several MHz with unprecedented flexibility and precision in pulse format. These new modulators can drive accelerators to high average powers that far exceed those of any other technology and can be used to enable precision beam manipulations. New insulator technology combined with novel pulse forming lines and switching may enable the construction of a new type of high gradient, high current accelerator. Recent developments in these areas will be reviewed.

  8. New accelerators in high-energy physics

    Energy Technology Data Exchange (ETDEWEB)

    Blewett, J.P.

    1982-01-01

    First, I should like to mention a few new ideas that have appeared during the last few years in the accelerator field. A couple are of importance in the design of injectors, usually linear accelerators, for high-energy machines. Then I shall review some of the somewhat sensational accelerator projects, now in operation, under construction or just being proposed. Finally, I propose to mention a few applications of high-energy accelerators in fields other than high-energy physics. I realize that this is a digression from my title but I hope that you will find it interesting.

  9. Future HEP Accelerators: The US Perspective

    Energy Technology Data Exchange (ETDEWEB)

    Bhat, Pushpalatha [Fermilab; Shiltsev, Vladimir [Fermilab

    2015-11-02

    Accelerator technology has advanced tremendously since the introduction of accelerators in the 1930s, and particle accelerators have become indispensable instruments in high energy physics (HEP) research to probe Nature at smaller and smaller distances. At present, accelerator facilities can be classified into Energy Frontier colliders that enable direct discoveries and studies of high mass scale particles and Intensity Frontier accelerators for exploration of extremely rare processes, usually at relatively low energies. The near term strategies of the global energy frontier particle physics community are centered on fully exploiting the physics potential of the Large Hadron Collider (LHC) at CERN through its high-luminosity upgrade (HL-LHC), while the intensity frontier HEP research is focused on studies of neutrinos at the MW-scale beam power accelerator facilities, such as Fermilab Main Injector with the planned PIP-II SRF linac project. A number of next generation accelerator facilities have been proposed and are currently under consideration for the medium- and long-term future programs of accelerator-based HEP research. In this paper, we briefly review the post-LHC energy frontier options, both for lepton and hadron colliders in various regions of the world, as well as possible future intensity frontier accelerator facilities.

  10. The Spallation Neutron Source accelerator system design

    Energy Technology Data Exchange (ETDEWEB)

    Henderson, S., E-mail: stuarth@fnal.gov [Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, TN 37831 (United States); Abraham, W. [Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (United States); Aleksandrov, A. [Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, TN 37831 (United States); Allen, C. [Techsource, Inc., 1475 Central Avenue, Suite 250, Los Alamos, NM 87544-3291 (United States); Alonso, J. [Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (United States); Anderson, D. [Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, TN 37831 (United States); Arenius, D. [Thomas Jefferson National Accelerator Facility, 12000 Jefferson Avenue, Newport News, VA 23606 (United States); Arthur, T. [Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, TN 37831 (United States); Assadi, S. [Techsource, Inc., 1475 Central Avenue, Suite 250, Los Alamos, NM 87544-3291 (United States); Ayers, J.; Bach, P. [Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (United States); Badea, V. [Brookhaven National Laboratory, P.O. Box 5000, Upton, NY 11973-5000 (United States); Battle, R. [Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, TN 37831 (United States); Beebe-Wang, J. [Brookhaven National Laboratory, P.O. Box 5000, Upton, NY 11973-5000 (United States); Bergmann, B.; Bernardin, J.; Bhatia, T.; Billen, J.; Birke, T.; Bjorklund, E. [Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, NM 87545 (United States); and others

    2014-11-01

    The Spallation Neutron Source (SNS) was designed and constructed by a collaboration of six U.S. Department of Energy national laboratories. The SNS accelerator system consists of a 1 GeV linear accelerator and an accumulator ring providing 1.4 MW of proton beam power in microsecond-long beam pulses to a liquid mercury target for neutron production. The accelerator complex consists of a front-end negative hydrogen-ion injector system, an 87 MeV drift tube linear accelerator, a 186 MeV side-coupled linear accelerator, a 1 GeV superconducting linear accelerator, a 248-m circumference accumulator ring and associated beam transport lines. The accelerator complex is supported by ∼100 high-power RF power systems, a 2 K cryogenic plant, ∼400 DC and pulsed power supply systems, ∼400 beam diagnostic devices and a distributed control system handling ∼100,000 I/O signals. The beam dynamics design of the SNS accelerator is presented, as is the engineering design of the major accelerator subsystems.

  11. Interactive analysis environment of unified accelerator libraries

    CERN Document Server

    Fine, V; Talman, R

    2006-01-01

    Unified Accelerator Libraries (UAL, http://www.ual.bnl.gov) software is an open accelerator simulation environment addressing a broad spectrum of accelerator tasks ranging from efficient online-oriented modeling to full-scale realistic beam dynamics studies. The paper introduces a new package integrating UAL simulation algorithms with the QT-based Graphical User Interface and the ROOT data analysis and visualization framework (http://root.cern.ch). The primary user application is implemented as an interactive and configurable Accelerator Physics Player. Its interface to visualization components is based on the QT layer (http://root.bnl.gov) supported by the STAR experiment.

  12. The Spallation Neutron Source accelerator system design

    Science.gov (United States)

    Henderson, S.; Abraham, W.; Aleksandrov, A.; Allen, C.; Alonso, J.; Anderson, D.; Arenius, D.; Arthur, T.; Assadi, S.; Ayers, J.; Bach, P.; Badea, V.; Battle, R.; Beebe-Wang, J.; Bergmann, B.; Bernardin, J.; Bhatia, T.; Billen, J.; Birke, T.; Bjorklund, E.; Blaskiewicz, M.; Blind, B.; Blokland, W.; Bookwalter, V.; Borovina, D.; Bowling, S.; Bradley, J.; Brantley, C.; Brennan, J.; Brodowski, J.; Brown, S.; Brown, R.; Bruce, D.; Bultman, N.; Cameron, P.; Campisi, I.; Casagrande, F.; Catalan-Lasheras, N.; Champion, M.; Champion, M.; Chen, Z.; Cheng, D.; Cho, Y.; Christensen, K.; Chu, C.; Cleaves, J.; Connolly, R.; Cote, T.; Cousineau, S.; Crandall, K.; Creel, J.; Crofford, M.; Cull, P.; Cutler, R.; Dabney, R.; Dalesio, L.; Daly, E.; Damm, R.; Danilov, V.; Davino, D.; Davis, K.; Dawson, C.; Day, L.; Deibele, C.; Delayen, J.; DeLong, J.; Demello, A.; DeVan, W.; Digennaro, R.; Dixon, K.; Dodson, G.; Doleans, M.; Doolittle, L.; Doss, J.; Drury, M.; Elliot, T.; Ellis, S.; Error, J.; Fazekas, J.; Fedotov, A.; Feng, P.; Fischer, J.; Fox, W.; Fuja, R.; Funk, W.; Galambos, J.; Ganni, V.; Garnett, R.; Geng, X.; Gentzlinger, R.; Giannella, M.; Gibson, P.; Gillis, R.; Gioia, J.; Gordon, J.; Gough, R.; Greer, J.; Gregory, W.; Gribble, R.; Grice, W.; Gurd, D.; Gurd, P.; Guthrie, A.; Hahn, H.; Hardek, T.; Hardekopf, R.; Harrison, J.; Hatfield, D.; He, P.; Hechler, M.; Heistermann, F.; Helus, S.; Hiatt, T.; Hicks, S.; Hill, J.; Hill, J.; Hoff, L.; Hoff, M.; Hogan, J.; Holding, M.; Holik, P.; Holmes, J.; Holtkamp, N.; Hovater, C.; Howell, M.; Hseuh, H.; Huhn, A.; Hunter, T.; Ilg, T.; Jackson, J.; Jain, A.; Jason, A.; Jeon, D.; Johnson, G.; Jones, A.; Joseph, S.; Justice, A.; Kang, Y.; Kasemir, K.; Keller, R.; Kersevan, R.; Kerstiens, D.; Kesselman, M.; Kim, S.; Kneisel, P.; Kravchuk, L.; Kuneli, T.; Kurennoy, S.; Kustom, R.; Kwon, S.; Ladd, P.; Lambiase, R.; Lee, Y. Y.; Leitner, M.; Leung, K.-N.; Lewis, S.; Liaw, C.; Lionberger, C.; Lo, C. C.; Long, C.; Ludewig, H.; Ludvig, J.; Luft, P.; Lynch, M.; Ma, H.; MacGill, R.; Macha, K.; Madre, B.; Mahler, G.; Mahoney, K.; Maines, J.; Mammosser, J.; Mann, T.; Marneris, I.; Marroquin, P.; Martineau, R.; Matsumoto, K.; McCarthy, M.; McChesney, C.; McGahern, W.; McGehee, P.; Meng, W.; Merz, B.; Meyer, R.; Meyer, R.; Miller, B.; Mitchell, R.; Mize, J.; Monroy, M.; Munro, J.; Murdoch, G.; Musson, J.; Nath, S.; Nelson, R.; Nelson, R.; O`Hara, J.; Olsen, D.; Oren, W.; Oshatz, D.; Owens, T.; Pai, C.; Papaphilippou, I.; Patterson, N.; Patterson, J.; Pearson, C.; Pelaia, T.; Pieck, M.; Piller, C.; Plawski, T.; Plum, M.; Pogge, J.; Power, J.; Powers, T.; Preble, J.; Prokop, M.; Pruyn, J.; Purcell, D.; Rank, J.; Raparia, D.; Ratti, A.; Reass, W.; Reece, K.; Rees, D.; Regan, A.; Regis, M.; Reijonen, J.; Rej, D.; Richards, D.; Richied, D.; Rode, C.; Rodriguez, W.; Rodriguez, M.; Rohlev, A.; Rose, C.; Roseberry, T.; Rowton, L.; Roybal, W.; Rust, K.; Salazer, G.; Sandberg, J.; Saunders, J.; Schenkel, T.; Schneider, W.; Schrage, D.; Schubert, J.; Severino, F.; Shafer, R.; Shea, T.; Shishlo, A.; Shoaee, H.; Sibley, C.; Sims, J.; Smee, S.; Smith, J.; Smith, K.; Spitz, R.; Staples, J.; Stein, P.; Stettler, M.; Stirbet, M.; Stockli, M.; Stone, W.; Stout, D.; Stovall, J.; Strelo, W.; Strong, H.; Sundelin, R.; Syversrud, D.; Szajbler, M.; Takeda, H.; Tallerico, P.; Tang, J.; Tanke, E.; Tepikian, S.; Thomae, R.; Thompson, D.; Thomson, D.; Thuot, M.; Treml, C.; Tsoupas, N.; Tuozzolo, J.; Tuzel, W.; Vassioutchenko, A.; Virostek, S.; Wallig, J.; Wanderer, P.; Wang, Y.; Wang, J. G.; Wangler, T.; Warren, D.; Wei, J.; Weiss, D.; Welton, R.; Weng, J.; Weng, W.-T.; Wezensky, M.; White, M.; Whitlatch, T.; Williams, D.; Williams, E.; Wilson, K.; Wiseman, M.; Wood, R.; Wright, P.; Wu, A.; Ybarrolaza, N.; Young, K.; Young, L.; Yourd, R.; Zachoszcz, A.; Zaltsman, A.; Zhang, S.; Zhang, W.; Zhang, Y.; Zhukov, A.

    2014-11-01

    The Spallation Neutron Source (SNS) was designed and constructed by a collaboration of six U.S. Department of Energy national laboratories. The SNS accelerator system consists of a 1 GeV linear accelerator and an accumulator ring providing 1.4 MW of proton beam power in microsecond-long beam pulses to a liquid mercury target for neutron production. The accelerator complex consists of a front-end negative hydrogen-ion injector system, an 87 MeV drift tube linear accelerator, a 186 MeV side-coupled linear accelerator, a 1 GeV superconducting linear accelerator, a 248-m circumference accumulator ring and associated beam transport lines. The accelerator complex is supported by ~100 high-power RF power systems, a 2 K cryogenic plant, ~400 DC and pulsed power supply systems, ~400 beam diagnostic devices and a distributed control system handling ~100,000 I/O signals. The beam dynamics design of the SNS accelerator is presented, as is the engineering design of the major accelerator subsystems.

  13. Accelerator Center for Energy Research (ACER)

    Data.gov (United States)

    Federal Laboratory Consortium — The Accelerator Center for Energy Research (ACER) exploits radiation chemistry techniques to study chemical reactions (and other phenomena) by subjecting samples to...

  14. Search for Dark Photons with Accelerators

    Directory of Open Access Journals (Sweden)

    Merkel Harald

    2014-01-01

    Full Text Available A dark photon as the mediator of an interaction of the dark sector is a well motivated extension of the standard model. While possible dark matter particles are heavy and seem to be beyond the reach of current accelerators, the dark photon is not necessarily heavy and might have a mass in the range of existing accelerators. In recent years, an extensive experimental program at several accelerators for the search for dark photons were established. In this talk, recent results and progress in the determination of exclusion limits with accelerators is presented.

  15. 2001 Snowmass Accelerator R and D Report

    Energy Technology Data Exchange (ETDEWEB)

    Chao, Alex W.

    2002-08-30

    The purpose of this report is to provide a perspective on future accelerator projects, and to identify the R&D activities necessary to prepare for these projects. The report summarizes the conclusions of accelerator studies made during the 2001 Snowmass Summer Study on the Future of Particle Physics. In doing so, it serves as a summary of the opinions on accelerator R&D expressed by the scientific community as it looks towards the next few decades. The main technical content is provided by the Executive Summaries of each of the fifteen accelerator Working Groups. These Working Group Executive Summaries form an integral part of this report.

  16. Acceleration of Advanced CN Antidote Agents for Mass Exposure Treatments: DMTS

    Science.gov (United States)

    2014-12-01

    c25 -5 0 5 15 30 45 60 90 -14 -12 -10 -8 -6 -4 -2 0 2 4 6 8 10 Time (min...DMTS IM DMTS 0.04cc IM Survival ΔH em og lo bi n (µ M ) DeOxyHb OxyHb bsln c25 -5 0 5 15 30 45 60 90 -14 -12 -10 -8 -6 -4 -2 0 2 4 6 8 10 Time (min...DMTS IM DMTS 3cc IM Survival ΔH em og lo bi n (µ M ) DeOxyHb OxyHb bsln c25 -5 0 5 15 30 45 60 90 -2.0 -1.8 -1.6 -1.4 -1.2 -1.0 -0.8 -0.6 -0.4 -0.2

  17. Nanosizing a Metal-Organic Framework Enzyme Carrier for Accelerating Nerve Agent Hydrolysis

    Science.gov (United States)

    2016-10-05

    30) Liang, K.; Ricco, R.; Doherty, C. M.; Styles, M. J.; Bell, S.; Kirby, N.; Mudie, S.; Haylock, D.; Hill, A. J.; Doonan, C. J.; et al. Biomimetic ...Ultrahigh Stability as Biomimetic Catalysts. Angew. Chem., Int. Ed. 2012, 51 (41), 10307−10310. (41) Mondloch, J. E.; Bury, W.; Fairen-Jimenez, D.; Kwon, S

  18. Project X: Accelerator Reference Design

    Energy Technology Data Exchange (ETDEWEB)

    Holmes, Stephen D. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)

    2013-06-20

    Project X is a high-intensity proton facility being developed to support a world-leading program of Intensity Frontier physics over the next two decades at Fermilab. Project X is an integral part of the U.S. Intensity Frontier Roadmap as described in the P5 report of May 2008 [1] and within the Fermilab Strategic Plan of November 2011 [2]. This document represents Part I of the “Project X Book” describing the Project X accelerator facility and the broad range of physics research opportunities enabled by Project X. Parts II and III provide in-depth descriptions of the physics research program, both within and beyond particle physics [3]. The primary elements of the U.S. program to be supported by Project X include: Neutrino Experiments: Experimental studies of neutrino oscillations and neutrino interaction physics with ultra-intense neutrino beams provided by a high-power proton source with energies up to 120 GeV, utilizing near detectors at the Fermilab site and massive detectors at distant underground laboratories. Goal: At least 2 MW of proton beam power at any energy between 60 to 120 GeV; several hundred kW of proton beam power on target at 8 GeV. Kaon, Muon, Nucleon, and Neutron Precision Experiments: World-leading experiments studying ultra-rare kaon decays, searching for muon-to-electron conversion and nuclear electron dipole moments (EDMs), and exploring neutron properties at very high precision. Goal: MW-class proton beams supporting multiple experiments at 1 and 3 GeV, with flexible capability for providing distinct beam formats to concurrent users while allowing simultaneous operations with the neutrino program. Material Science and Nuclear Energy Applications: High-intensity accelerator, spallation, target and transmutation technology demonstrations will provide critical input into the design of future energy systems, including next generation fission reactors, nuclear waste transmutation systems and future thorium fuel-cycle power systems. Possible

  19. Controlling the Solidification of Organic Photovoltaic Blends with Nucleating Agents

    KAUST Repository

    Nekuda Malik, Jennifer A.

    2014-11-20

    Blending fullerenes with a donor polymer for the fabrication of organic solar cells often leads to at least partial vitrification of one, if not both, components. For prototypical poly(3-hexylthiophene):fullerene blend, we show that the addition of a commercial nucleating agent, di(3,4-dimethyl benzylidene)sorbitol, to such binary blends accelerates the crystallization of the donor, resulting in an increase in its degree of crystallinity in as-cast structures. This allows manipulation of the extent of intermixing/ phase separation of the donor and acceptor directly from solution, offering a tool to improve device characteristics such as power conversion efficiency.

  20. Beam-commissioning study of high-intensity accelerators using virtual accelerator model

    OpenAIRE

    Harada, Hiroyuki; Shigaki, Kenta; Irie, Yoshiro; Noda, Fumiaki; Hocchi, Hideaki; Saha, Pranab Kumar; Shobuda, Yoshihiro; Sako, Hiroyuki; Furukawa, Kazuro; Machida, Shinji

    2009-01-01

    In order to control large-scale accelerators efficiently, a control system with a virtual accelerator model was constructed. The virtual accelerator (VA) is an on-line beam simulator provided with a beam monitor scheme. The VA is based upon the Experimental Physics and Industrial Control System (EPICS) and is configured under the EPICS input/output controller (IOC) in parallel with a real accelerator (RA). Thus, the machine operator can access the parameters of the RA through the channel acce...

  1. LTB universes as alternatives to dark energy: does positive averaged acceleration imply positive cosmic acceleration?

    OpenAIRE

    Romano, Antonio Enea

    2006-01-01

    We show that positive averaged acceleration obtained in LTB models through spatial averaging can require integration over a region beyond the event horizon of the central observer. We provide an example of a LTB model with positive averaged acceleration in which the luminosity distance does not contain information about the entire spatially averaged region, making the averaged acceleration unobservable. Since the cosmic acceleration is obtained from fitting the observed luminosity distance to...

  2. Agent Communications using Distributed Metaobjects

    Energy Technology Data Exchange (ETDEWEB)

    Goldsmith, Steven Y.; Spires, Shannon V.

    1999-06-10

    There are currently two proposed standards for agent communication languages, namely, KQML (Finin, Lobrou, and Mayfield 1994) and the FIPA ACL. Neither standard has yet achieved primacy, and neither has been evaluated extensively in an open environment such as the Internet. It seems prudent therefore to design a general-purpose agent communications facility for new agent architectures that is flexible yet provides an architecture that accepts many different specializations. In this paper we exhibit the salient features of an agent communications architecture based on distributed metaobjects. This architecture captures design commitments at a metaobject level, leaving the base-level design and implementation up to the agent developer. The scope of the metamodel is broad enough to accommodate many different communication protocols, interaction protocols, and knowledge sharing regimes through extensions to the metaobject framework. We conclude that with a powerful distributed object substrate that supports metaobject communications, a general framework can be developed that will effectively enable different approaches to agent communications in the same agent system. We have implemented a KQML-based communications protocol and have several special-purpose interaction protocols under development.

  3. Gas breakdown limit and maximum acceleration gradient for inverse Cherenkov laser accelerator

    CERN Document Server

    Liu, Y; Cline, D

    1999-01-01

    Laser intensity thresholds for CO sub 2 laser-induced gas breakdown, such as tunneling, multiphoton, and cascade ionization have been estimated for the inverse Cherenkov accelerator experiment at the Brookhaven Accelerator Test Facility. The gas breakdown is dominated by cascade ionization and the maximum acceleration gradient is up to 300 MeV/m for a 3 ps CO sub 2 laser.

  4. Biology of melanogenesis and the search for hypopigmenting agents

    Directory of Open Access Journals (Sweden)

    Kyoung-Chan Park

    2010-06-01

    Full Text Available Increased production and accumulation of melanin are characteristics of a large number of skin diseases, including melasma, post-inflammatory hyperpigmentation and lentigo. A number of clinical agents can reduce normal or abnormal pigmentation, but none of these have achieved satisfactory effects. This review discusses the mechanisms behind the different approaches. Tyrosinase is a pivotal enzyme in melanin synthesis. The majority of whitening or lightening agents act by specifically reducing the activity of tyrosinase via several mechanisms: (1 prior to melanin synthesis (interfering with its transcription and/or glycosylation; (2 during melanin synthesis (tyrosinase inhibition, peroxidase inhibition and reduction of byproducts; and (3 after melanin synthesis (tyrosinase degradation, inhibition of melanosome transfer, acceleration of skin turnover. Additional melanogenesis-associated mechanisms are also discussed.

  5. Nuclear magnetic resonance contrast agents

    Science.gov (United States)

    Smith, P.H.; Brainard, J.R.; Jarvinen, G.D.; Ryan, R.R.

    1997-12-30

    A family of contrast agents for use in magnetic resonance imaging and a method of enhancing the contrast of magnetic resonance images of an object by incorporating a contrast agent of this invention into the object prior to forming the images or during formation of the images. A contrast agent of this invention is a paramagnetic lanthanide hexaazamacrocyclic molecule, where a basic example has the formula LnC{sub 16}H{sub 14}N{sub 6}. Important applications of the invention are in medical diagnosis, treatment, and research, where images of portions of a human body are formed by means of magnetic resonance techniques. 10 figs.

  6. An Introduction to Software Agents

    Science.gov (United States)

    2008-02-01

    détruire une unité de valeur élevée »). Le fait d’avoir des forces rouges ayant des comportements réalistes est essentiel au succès d’une expérience...agent, but more likely it will consist of multiple agents. The following attributes are only applicable in a multi-agent system: 9. Social ...communication ( social ability) and cooperation. The final two characteristics that will be mentioned here are more related to the capability of the

  7. Electron accelerating unit for streak image tubes

    Indian Academy of Sciences (India)

    The distance between the cathode and the mesh is 1.2 mm. The electric field in the cathode-to-mesh region is a self-focusing field, which can reduce the electron beam size. There are three advantages of the accelerating unit. In the pulsed mode, a pulsed voltage is applied to the accelerating electrode. First, the SIT works ...

  8. Present status of TIARA electrostatic accelerator facility

    Energy Technology Data Exchange (ETDEWEB)

    Tajima, Satoshi; Takada, Isao; Mizuhashi, Kiyoshi; Saito, Yuichi; Uno, Sadanori; Okoshi, Kiyonori; Ishii, Yasuyuki; Nakajima, Yoshinori; Sakai, Takuro [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

    1996-12-01

    The electrostatic accelerator, 3 MV tandem accelerator, 3 MV single end accelerator and 400 kV ion implantation equipment, which were installed in Takasaki Ion Irradiation Research Facility (TIARA) of Japan Atomic Energy Research Institute, have been used for the research on the advanced utilization of radiation mainly in material science by ion beam. The utilization is open to other researchers, and in fiscal year 1995, about 40% was the utilization by outsiders. The number of the experimental subjects adopted in fiscal year 1995 was 47, and the fields of research were space and environment materials, nuclear fusion reactor materials, new functional materials, biotechnology and base technology. The operation time in fiscal year 1995 was 1201, 1705 and 1505 hours for the tandem accelerator, single end accelerator and ion implantation equipment, respectively. The methods of experiment are reported. The troubles occurred in the tandem accelerator and single end accelerator are reported. As the diversification of beam utilization in the tandem accelerator, the utilizations of high energy molecular ions, low energy negative ions, multivalent ions by post stripper and low intensity ions by mesh attenuator have been attempted. These utilizations are described. (K.I.)

  9. A Survey of Hadron Therapy Accelerator Technologies.

    Energy Technology Data Exchange (ETDEWEB)

    PEGGS,S.; SATOGATA, T.; FLANZ, J.

    2007-06-25

    Hadron therapy has entered a new age [1]. The number of facilities grows steadily, and 'consumer' interest is high. Some groups are working on new accelerator technology, while others optimize existing designs by reducing capital and operating costs, and improving performance. This paper surveys the current requirements and directions in accelerator technology for hadron therapy.

  10. Characteristics of diffusion flames with accelerated motion

    Directory of Open Access Journals (Sweden)

    Lou Bo

    2016-01-01

    Full Text Available The aim of this work is to present an experiment to study the characteristics of a laminar diffusion flame under acceleration. A Bunsen burner (nozzle diameter 8 mm, using liquefied petroleum gas as its fuel, was ignited under acceleration. The temperature field and the diffusion flame angle of inclination were visualised with the assistance of the visual display technology incorporated in MATLAB™. Results show that the 2-d temperature field under different accelerations matched the variation in average temperatures: they both experience three variations at different time and velocity stages. The greater acceleration has a faster change in average temperature with time, due to the accumulation of combustion heat: the smaller acceleration has a higher average temperature at the same speed. No matter what acceleration was used, in time, the flame angle of inclination increased, but the growth rate decreased until an angle of 90°: this could be explained by analysis of the force distribution within the flame. It is also found that, initially, the growth rate of angle with velocity under the greater acceleration was always smaller than that at lower accelerations; it was also different in flames with uniform velocity fire conditions.

  11. Particle acceleration in a plasma filled IFEL

    Science.gov (United States)

    Gürsey, Yusuf

    1989-10-01

    An earlier proposal by J. L. Bobin1,2 to accelerate particles using a laser, undulator magnet, particle beam, and plasma is elaborated upon. The current status of research on the subject is presented, including problems and prospects. Estimates are given for parameters of an experiment at the Accelerator Test Facility at Brookhaven National Laboratory.

  12. Measurement of Coriolis Acceleration with a Smartphone

    Science.gov (United States)

    Shaku, Asif; Kraft, Jakob

    2016-01-01

    Undergraduate physics laboratories seldom have experiments that measure the Coriolis acceleration. This has traditionally been the case owing to the inherent complexities of making such measurements. Articles on the experimental determination of the Coriolis acceleration are few and far between in the physics literature. However, because modern…

  13. The CSU Accelerator and FEL Facility

    NARCIS (Netherlands)

    Milton, S.V.; Biedron, S.G.; Burleson, T.; Carrico, C.; Edelenbos, J.; Hall, C.; Horovitz, K.; Morin, A.; Rand, L.; Sipahi, N.; Sipahi, T.; van der Slot, P.; Yehudah, H.; Dong, A.; Tanaka, T.; Schaa, V.R.W.

    2013-01-01

    The Colorado State University (CSU) Accelerator Facility will include a 6-MeV L-Band electron linear accelerator (linac) with a free-electron laser (FEL) system capable of producing Terahertz (THz) radiation, a laser laboratory, a microwave test stand, and a magnetic test stand. The photocathode

  14. Vibrational Stability of NLC Linac Accelerating Structure

    CERN Document Server

    Le Pimpec, F; Bowden, G B; Doyle, E; McKee, B; Seryi, Andrei; Redaelli, S; Adiga, S

    2002-01-01

    The vibration of components of the NLC linac, such as accelerating structures and girders, is being studied both experimentally and analytically. Various effects are being considered including structural resonances and vibration caused by cooling water in the accelerating structure. This paper reports the status of ongoing work.

  15. Accelerated idioventricular rhythm during flexible fiberoptic bronchoscopy

    Energy Technology Data Exchange (ETDEWEB)

    Borgeat, A.; Chiolero, R.; Mosimann, B.; Freeman, J.

    1987-03-01

    We report the case of a patient who developed severe hypoxemia and an unusual arrhythmia, accelerated idioventricular rhythm, during flexible fiberoptic bronchoscopy. Coronary artery disease was subsequently suspected despite an unremarkable history and physical examination, and confirmed by a thallium 201 imaging. The appearance of accelerated idioventricular rhythm during fiberoptic bronchoscopy should raise the possibility of underlying coronary artery disease.

  16. 5 CFR 179.308 - Accelerated procedures.

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Accelerated procedures. 179.308 Section 179.308 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS CLAIMS COLLECTION STANDARDS Administrative Offset § 179.308 Accelerated procedures. OPM may make an administrative...

  17. Sunitinib Does Not Accelerate Tumor Growth in Patients with Metastatic Renal Cell Carcinoma

    Directory of Open Access Journals (Sweden)

    Krastan B. Blagoev

    2013-02-01

    Full Text Available Preclinical studies have suggested that sunitinib accelerates metastases in animals, ascribing this to inhibition of the vascular endothelial growth factor receptor or the tumor’s adaptation. To address whether sunitinib accelerates tumors in humans, we analyzed data from the pivotal randomized phase III trial comparing sunitinib and interferon alfa in patients with metastatic renal cell carcinoma. The evidence clearly shows that sunitinib was not harmful, did not accelerate tumor growth, and did not shorten survival. Specifically, neither longer sunitinib treatment nor a greater effect of sunitinib on tumors reduced survival. Sunitinib did reduce the tumor’s growth rate while administered, thereby improving survival, without appearing to alter tumor biology after discontinuation. Concerns arising from animal models do not apply to patients receiving sunitinib and likely will not apply to similar agents.

  18. Progress toward NLC / GLC prototype accelerator structures

    CERN Document Server

    Wang, J W; Arkan, T; Baboi, N; Boffo, C; Bowden, G B; Burke, D L; Carter, H; Chan, J; Cornuelle, J; Döbert, Steffen; Dolgashev, Valery A; Finley, D; Gonin, I; Higashi, Y; Higo, T; Jones, R M; Khabiboulline, T; Kume, T; Lewandowski, J; Li, Z; Miller, R H; Mishra, S; Morozumi, Y; Nantista, C; Pearson, C; Romanov, G; Ruth, Ronald D; Solyak, N; Tantawi, S; Toge, N; Ueno, K; Wilson, P B; Xiao, L

    2004-01-01

    The accelerator structure groups for NLC (Next Linear Collider) and GLC (Global Linear Colliders) have successfully collaborated on the research and development of a major series of advanced accelerator structures based on room-temperature technology at X-band frequency. The progress in design, simulation, microwave measurement and high gradient tests are summarized in this paper. The recent effort in design and fabrication of the accelerator structure prototype for the main linac is presented in detail including HOM (High Order Mode) suppression and couplers, fundamental mode couplers, optimized accelerator cavities as well as plans for future structures. We emphasize techniques to reduce the field on the surface of the copper structures (in order to achieve high accelerating gradients), limit the dipole wakefields (to relax alignment tolerance and prevent a beam break up instability) and improve shunt impedance (to reduce the RF power required).

  19. The hardware accelerator array for logic simulation

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, N H [Washington State Univ., Pullman, WA (USA)

    1991-05-01

    Hardware acceleration exploits the parallelism inherent in large circuit simulations to achieve significant increases in performance. Simulation accelerators have been developed based on the compiled code algorithm or the event-driven algorithm. The greater flexibility of the event-driven algorithm has resulted in several important developments in hardware acceleration architecture. Some popular commercial products have been developed based on the event-driven algorithm and data-flow architectures. Conventional data-flow architectures require complex switching networks to distribute operands among processing elements resulting in considerable overhead. An accelerator array architecture based on a nearest-neighbor communication has been developed in this thesis. The design is simulated in detail at the behavioral level. Its performance is evaluated and shown to be superior to that of a conventional data-flow accelerator. 14 refs., 48 figs., 5 tabs.

  20. On the structure of acceleration in turbulence

    DEFF Research Database (Denmark)

    Liberzon, A.; Lüthi, B.; Holzner, M.

    2012-01-01

    Acceleration and spatial velocity gradients are obtained simultaneously in an isotropic turbulent flow via three dimensional particle tracking velocimetry. We observe two distinct populations of intense acceleration events: one in flow regions of strong strain and another in regions of strong...... vorticity. Geometrical alignments with respect to vorticity vector and to the strain eigenvectors, curvature of Lagrangian trajectories and of streamlines for total acceleration, and for its convective part, , are studied in detail. We discriminate the alignment features of total and convective acceleration...... statistics, which are genuine features of turbulent nature from those of kinematic nature. We find pronounced alignment of acceleration with vorticity. Similarly, and especially are predominantly aligned at 45°with the most stretching and compressing eigenvectors of the rate of the strain tensor...

  1. Psychological effects of thought acceleration.

    Science.gov (United States)

    Pronin, Emily; Jacobs, Elana; Wegner, Daniel M

    2008-10-01

    Six experiments found that manipulations that increase thought speed also yield positive affect. These experiments varied in both the methods used for accelerating thought (i.e., instructions to brainstorm freely, exposure to multiple ideas, encouragement to plagiarize others' ideas, performance of easy cognitive tasks, narration of a silent video in fast-forward, and experimentally controlled reading speed) and the contents of the thoughts that were induced (from thoughts about money-making schemes to thoughts of five-letter words). The results suggested that effects of thought speed on mood are partially rooted in the subjective experience of thought speed. The results also suggested that these effects can be attributed to the joy-enhancing effects of fast thinking (rather than only to the joy-killing effects of slow thinking). This work is inspired by observations of a link between "racing thoughts" and euphoria in cases of clinical mania, and potential implications of that observed link are discussed. (c) 2008 APA, all rights reserved

  2. A particle accelerator probes artifacts

    CERN Document Server

    Dran, J C; Salomon, J

    2002-01-01

    The AGLAE system is made up of a 2 mega volts electrostatic accelerator and of 3 irradiation lines: one leads to a vacuum enclosure in which targets are irradiated and the 2 others lines are designed to irradiate targets under an air or helium atmosphere. The AGLAE system is located in the premises of the Louvre museum in Paris and is devoted to the study of cultural objects through ion beam analysis (IBA). 4 techniques are used: -) proton-induced X-ray emission (PIXE) -) proton-induced gamma ray (PIGE) -) Rutherford backscattering spectrometry (NRS) and -) nuclear reaction analysis (NRA). A decisive progress has permitted the direct analysis of artifacts without sampling. The object itself is set just a few millimeters away from the exit window of the beam in an air or helium atmosphere. The exit window must be resistant enough to bear the atmospheric pressure and the damages caused by the proton beam but must be thin enough to not deteriorate the quality of the beam. By using a 10 sup - sup 7 m thick exit w...

  3. Accelerating the Original Profile Kernel.

    Science.gov (United States)

    Hamp, Tobias; Goldberg, Tatyana; Rost, Burkhard

    2013-01-01

    One of the most accurate multi-class protein classification systems continues to be the profile-based SVM kernel introduced by the Leslie group. Unfortunately, its CPU requirements render it too slow for practical applications of large-scale classification tasks. Here, we introduce several software improvements that enable significant acceleration. Using various non-redundant data sets, we demonstrate that our new implementation reaches a maximal speed-up as high as 14-fold for calculating the same kernel matrix. Some predictions are over 200 times faster and render the kernel as possibly the top contender in a low ratio of speed/performance. Additionally, we explain how to parallelize various computations and provide an integrative program that reduces creating a production-quality classifier to a single program call. The new implementation is available as a Debian package under a free academic license and does not depend on commercial software. For non-Debian based distributions, the source package ships with a traditional Makefile-based installer. Download and installation instructions can be found at https://rostlab.org/owiki/index.php/Fast_Profile_Kernel. Bugs and other issues may be reported at https://rostlab.org/bugzilla3/enter_bug.cgi?product=fastprofkernel.

  4. Accelerating the Original Profile Kernel.

    Directory of Open Access Journals (Sweden)

    Tobias Hamp

    Full Text Available One of the most accurate multi-class protein classification systems continues to be the profile-based SVM kernel introduced by the Leslie group. Unfortunately, its CPU requirements render it too slow for practical applications of large-scale classification tasks. Here, we introduce several software improvements that enable significant acceleration. Using various non-redundant data sets, we demonstrate that our new implementation reaches a maximal speed-up as high as 14-fold for calculating the same kernel matrix. Some predictions are over 200 times faster and render the kernel as possibly the top contender in a low ratio of speed/performance. Additionally, we explain how to parallelize various computations and provide an integrative program that reduces creating a production-quality classifier to a single program call. The new implementation is available as a Debian package under a free academic license and does not depend on commercial software. For non-Debian based distributions, the source package ships with a traditional Makefile-based installer. Download and installation instructions can be found at https://rostlab.org/owiki/index.php/Fast_Profile_Kernel. Bugs and other issues may be reported at https://rostlab.org/bugzilla3/enter_bug.cgi?product=fastprofkernel.

  5. ACCELERATED SOLVENT EXTRACTION COMBINED WITH ...

    Science.gov (United States)

    A research project was initiated to address a recurring problem of elevated detection limits above required risk-based concentrations for the determination of semivolatile organic compounds in high moisture content solid samples. This project was initiated, in cooperation with the EPA Region 1 Laboratory, under the Regional Methods Program administered through the ORD Office of Science Policy. The aim of the project was to develop an approach for the rapid removal of water in high moisture content solids (e.g., wetland sediments) in preparation for analysis via Method 8270. Alternative methods for water removal have been investigated to enhance compound solid concentrations and improve extraction efficiency, with the use of pressure filtration providing a high-throughput alternative for removal of the majority of free water in sediments and sludges. In order to eliminate problems with phase separation during extraction of solids using Accelerated Solvent Extraction, a variation of a water-isopropanol extraction method developed at the USGS National Water Quality Laboratory in Denver, CO is being employed. The concentrations of target compounds in water-isopropanol extraction fluids are subsequently analyzed using an automated Solid Phase Extraction (SPE)-GC/MS method developed in our laboratory. The coupled approaches for dewatering, extraction, and target compound identification-quantitation provide a useful alternative to enhance sample throughput for Me

  6. Accelerating Topical Anaesthesia Using Microneedles.

    Science.gov (United States)

    Davies, Lleucu B; Gateley, Christopher; Holland, Phillip; Coulman, Siôn A; Birchall, James C

    2017-09-08

    Topical anaesthetics reduce pain during venous access procedures in children. However, clinical use is hindered by a significant anaesthetic onset time. Restricted diffusion of the topical anaesthetic through the stratum corneum barrier is the principal reason for the delayed onset. Microneedles can painlessly pierce the skin. This study evaluated microneedle pre-treatment of ex vivo human skin as a means to increase the rate of tetracaine permeation, in order to accelerate the onset of anaesthesia. Franz-type diffusion cells were used to determine permeation of a commercial tetracaine formulation, Ametop gel, through human skin epidermis. Microneedle-assisted permeation was compared to untreated epidermis. Upon completion of the permeation studies, the epidermal membranes were visually characterised. At 30 min, 5.43 µg/cm2 of tetracaine had permeated through the untreated membrane compared to 12.13 µg/cm2 through the microneedle-treated membrane. Insertion of a hypodermic needle created a large single channel in the epidermis (approx. 4,250 μm2) whilst the punctured surface area following microneedle treatments was estimated to be 75,000 μm2. Pre-treatment of skin with microneedles significantly enhances the permeation of tetracaine. Microneedles have the potential to more than halve the onset time for anaesthesia when applying Ametop gel. © 2017 S. Karger AG, Basel.

  7. Plasma wakefield acceleration experiments at FACET II

    Science.gov (United States)

    Joshi, C.; Adli, E.; An, W.; Clayton, C. E.; Corde, S.; Gessner, S.; Hogan, M. J.; Litos, M.; Lu, W.; Marsh, K. A.; Mori, W. B.; Vafaei-Najafabadi, N.; O’shea, B.; Xu, Xinlu; White, G.; Yakimenko, V.

    2018-03-01

    During the past two decades of research, the ultra-relativistic beam-driven plasma wakefield accelerator (PWFA) concept has achieved many significant milestones. These include the demonstration of ultra-high gradient acceleration of electrons over meter-scale plasma accelerator structures, efficient acceleration of a narrow energy spread electron bunch at high-gradients, positron acceleration using wakes in uniform plasmas and in hollow plasma channels, and demonstrating that highly nonlinear wakes in the ‘blow-out regime’ have the electric field structure necessary for preserving the emittance of the accelerating bunch. A new 10 GeV electron beam facility, Facilities for Accelerator Science and Experimental Test (FACET) II, is currently under construction at SLAC National Accelerator Laboratory for the next generation of PWFA research and development. The FACET II beams will enable the simultaneous demonstration of substantial energy gain of a small emittance electron bunch while demonstrating an efficient transfer of energy from the drive to the trailing bunch. In this paper we first describe the capabilities of the FACET II facility. We then describe a series of PWFA experiments supported by numerical and particle-in-cell simulations designed to demonstrate plasma wake generation where the drive beam is nearly depleted of its energy, high efficiency acceleration of the trailing bunch while doubling its energy and ultimately, quantifying the emittance growth in a single stage of a PWFA that has optimally designed matching sections. We then briefly discuss other FACET II plasma-based experiments including in situ positron generation and acceleration, and several schemes that are promising for generating sub-micron emittance bunches that will ultimately be needed for both an early application of a PWFA and for a plasma-based future linear collider.

  8. Antisense Treatments for Biothreat Agents

    National Research Council Canada - National Science Library

    Warfield, Kelly L; Panchal, Rekha G; Aman, M J; Bavari, Sina

    2006-01-01

    ... a variety of pathogens in cell culture studies and nonhuman primate models of infection. For these reasons, antisense technologies are being pursued as treatments against biothreat agents such as Ebola virus, dengue virus and Bacillus anthracis...

  9. Building Agents to Serve Customers

    OpenAIRE

    Barbuceanu, Mihai; Fox, Mark S; Hong, Lei; Lallement, Yannick; Zhang, Zhongdong

    2004-01-01

    AI agents combining natural language interaction, task planning, and business ontologies can help companies provide better-quality and more costeffective customer service. Our customer-service agents use natural language to interact with customers, enabling customers to state their intentions directly instead of searching for the places on the Web site that may address their concern. We use planning methods to search systematically for the solution to the customer's problem, ensuring that a r...

  10. Believable Social and Emotional Agents.

    Science.gov (United States)

    1996-05-01

    AGENTS v Acknowledgements I would like the thank my advisors, Joe and Jaime. When you get to CMU as a first year graduate student , you’re told that...failure traits is “ depressed .” A depressed agent, according to this theory, will often respond to failures by being more like- ly to abandon the plan and...forms of distress expression, like frowning, crying, and moving slowly. Below that type might be subtypes, such as grief, homesick - ness, and

  11. Business Intelligence using Software Agents

    OpenAIRE

    Ana-Ramona BOLOGA; Razvan BOLOGA

    2011-01-01

    This paper presents some ideas about business intelligence today and the importance of developing real time business solutions. The authors make an exploration of links between business intelligence and artificial intelligence and focuses specifically on the implementation of software agents-based systems in business intelligence. There are briefly presented some of the few solutions proposed so far that use software agents properties for the benefit of business intelligence. The authors then...

  12. Natural products as antimitotic agents.

    Science.gov (United States)

    Dall'Acqua, Stefano

    2014-01-01

    Natural products still play an important role in the medicinal chemistry, especially in some therapeutic areas. As example more than 60% of currently-used anticancer agents are derives from natural sources including plants, marine organisms or micro-organism. Thus natural products (NP) are an high-impact source of new "lead compounds" or new potential therapeutic agents despite the large development of biotechnology and combinatorial chemistry in the drug discovery and development. Many examples of anticancer drugs as paclitaxel, combretastatin, bryostatin and discodermolide have shown the importance of NP in the anticancer chemotherapy through many years. Many organisms have been studied as sources of drugs namely plants, micro-organisms and marine organisms and the obtained NP can be considered a group of "privileged chemical structures" evolved in nature to interact with other organisms. For this reason NP are a good starting points for pharmaceutical research and also for library design. Tubulin and microtubules are one of the most studied targets for the search of anticancer compounds. Microtubule targeting agents (MTA) also named antimitotic agents are compounds that are able to perturb mitosis but are also able to arrest cell growing during interphase. The anticancer drugs, taxanes and vinca alkaloids have established tubulin as important target in cancer therapy. More recently the vascular disrupting agents (VDA) combretastatin analogues were studied for their antimitotics properties. This review will consider the anti mitotic NP and their potential impact in the development of new therapeutic agents.

  13. Mobile Objects and Agents (MOA)

    Science.gov (United States)

    Milojicic, Dejan S.; LaForge, William; Chauhan, Deepika

    1998-12-01

    This paper describes the design and implementation of the Mobile Objects and Agents (MOA) project at the Open Group Research Institute. MOA was designed to support migration, communication and control of agents. It was implemented on top of the Java Virtual Machine, without any modifications to it. The initial project goals were to support communication across agent migration, as a means for collaborative work; and to provide extensive resource control, as a basic support for countering denial of service attacks. In the course of the project we added two further goals: compliance with the Java Beans component model, which provides for additional configurability and customization of agent system and agent applications; and interoperability, which allows cooperation with other agent systems. This paper analyses the architecture of MOA, in particular the support for mobility, naming and locating, communication, and resource management. Object and component models of MOA are discussed and some implementation details described. We summarize the lessons learned while developing and implementing MOA and compare it with related work.

  14. What makes virtual agents believable?

    Science.gov (United States)

    Bogdanovych, Anton; Trescak, Tomas; Simoff, Simeon

    2016-01-01

    In this paper we investigate the concept of believability and make an attempt to isolate individual characteristics (features) that contribute to making virtual characters believable. As the result of this investigation we have produced a formalisation of believability and based on this formalisation built a computational framework focused on simulation of believable virtual agents that possess the identified features. In order to test whether the identified features are, in fact, responsible for agents being perceived as more believable, we have conducted a user study. In this study we tested user reactions towards the virtual characters that were created for a simulation of aboriginal inhabitants of a particular area of Sydney, Australia in 1770 A.D. The participants of our user study were exposed to short simulated scenes, in which virtual agents performed some behaviour in two different ways (while possessing a certain aspect of believability vs. not possessing it). The results of the study indicate that virtual agents that appear resource bounded, are aware of their environment, own interaction capabilities and their state in the world, agents that can adapt to changes in the environment and exist in correct social context are those that are being perceived as more believable. Further in the paper we discuss these and other believability features and provide a quantitative analysis of the level of contribution for each such feature to the overall perceived believability of a virtual agent.

  15. Probing electron acceleration and X-ray emission in laser-plasma accelerator

    CERN Document Server

    Thaury, C; Corde, S; Brijesh, P; Lambert, G; Mangles, S P D; Bloom, M S; Kneip, S; Malka, V

    2013-01-01

    While laser-plasma accelerators have demonstrated a strong potential in the acceleration of electrons up to giga-electronvolt energies, few experimental tools for studying the acceleration physics have been developed. In this paper, we demonstrate a method for probing the acceleration process. A second laser beam, propagating perpendicular to the main beam is focused in the gas jet few nanosecond before the main beam creates the accelerating plasma wave. This second beam is intense enough to ionize the gas and form a density depletion which will locally inhibit the acceleration. The position of the density depletion is scanned along the interaction length to probe the electron injection and acceleration, and the betatron X-ray emission. To illustrate the potential of the method, the variation of the injection position with the plasma density is studied.

  16. Role of Direct Laser Acceleration of Electrons in a Laser Wakefield Accelerator with Ionization Injection.

    Science.gov (United States)

    Shaw, J L; Lemos, N; Amorim, L D; Vafaei-Najafabadi, N; Marsh, K A; Tsung, F S; Mori, W B; Joshi, C

    2017-02-10

    We show the first experimental demonstration that electrons being accelerated in a laser wakefield accelerator operating in the forced or blowout regimes gain significant energy from both the direct laser acceleration (DLA) and the laser wakefield acceleration mechanisms. Supporting full-scale 3D particle-in-cell simulations elucidate the role of the DLA of electrons in a laser wakefield accelerator when ionization injection of electrons is employed. An explanation is given for how electrons can maintain the DLA resonance condition in a laser wakefield accelerator despite the evolving properties of both the drive laser and the electrons. The produced electron beams exhibit characteristic features that are indicative of DLA as an additional acceleration mechanism.

  17. Operational Radiation Protection in High-Energy Physics Accelerators: Implementation of ALARA in Design and Operation of Accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Fasso, A.; Rokni, S.; /SLAC

    2011-06-30

    It used to happen often, to us accelerator radiation protection staff, to be asked by a new radiation worker: ?How much dose am I still allowed?? And we smiled looking at the shocked reaction to our answer: ?You are not allowed any dose?. Nowadays, also thanks to improved training programs, this kind of question has become less frequent, but it is still not always easy to convince workers that staying below the exposure limits is not sufficient. After all, radiation is still the only harmful agent for which this is true: for all other risks in everyday life, from road speed limits to concentration of hazardous chemicals in air and water, compliance to regulations is ensured by keeping below a certain value. It appears that a tendency is starting to develop to extend the radiation approach to other pollutants (1), but it will take some time before the new attitude makes it way into national legislations.

  18. Centrifugal acceleration in the magnetotail lobes

    Directory of Open Access Journals (Sweden)

    H. Nilsson

    2010-02-01

    Full Text Available Combined Cluster EFW and EDI measurements have shown that cold ion outflow in the magnetospheric lobes dominates the hydrogen ion outflow from the Earth's atmosphere. The ions have too low kinetic energy to be measurable with particle instruments, at least for the typical spacecraft potential of a sunlit spacecraft in the tenuous lobe plasmas outside a few RE. The measurement technique yields both density and bulk velocity, which can be combined with magnetic field measurements to estimate the centrifugal acceleration experienced by these particles. We present a quantitative estimate of the centrifugal acceleration, and the velocity change with distance which we would expect due to centrifugal acceleration. It is found that the centrifugal acceleration is on average outward with an average value of about of 5 m s−2. This is small, but acting during long transport times and over long distances the cumulative effect is significant, while still consistent with the relatively low velocities estimated using the combination of EFW and EDI data. The centrifugal acceleration should accelerate any oxygen ions in the lobes to energies observable by particle spectrometers. The data set also put constraints on the effectiveness of any other acceleration mechanisms acting in the lobes, where the total velocity increase between 5 and 19 RE geocentric distance is less than 5 km s−1.

  19. A new awakening for accelerator cavities

    CERN Multimedia

    Katarina Anthony

    2013-01-01

    Imagine: an accelerator unbound by length; one that can bring a beam up to the TeV level in just a few hundred metres. Sounds like a dream? Perhaps not for long. At CERN’s Proton Driven Plasma Wakefield Acceleration Experiment (AWAKE), physicists may soon be working to bring this contemporary fairy-tale to life.   The AWAKE experiment in the CNGS facility. Wherever you find a modern linear particle accelerator, you’ll find with it a lengthy series of RF accelerating cavities. Although based on technology first developed over half a century ago, RF cavities have dominated the accelerating world since their inception. However, new developments in plasma accelerator systems may soon be bringing a new player into the game. By harnessing the power of wakefields generated by beams in plasma cells, physicists may be able to produce accelerator gradients of many GV/m –  hundreds of times higher than those achieved in current RF cavities. “Plasma wakef...

  20. Rf cavity primer for cyclic proton accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Griffin, J.E.

    1988-04-01

    The purpose of this note is to describe the electrical and mechanical properites of particle accelerator rf cavities in a manner which will be useful to physics and engineering graduates entering the accelerator field. The discussion will be limited to proton (or antiproton) synchrotron accelerators or storage rings operating roughly in the range of 20 to 200 MHz. The very high gradient, fixed frequency UHF or microwave devices appropriate for electron machines and the somewhat lower frequency and broader bandwidth devices required for heavy ion accelerators are discussed extensively in other papers in this series. While it is common pratice to employ field calculation programs such as SUPERFISH, URMEL, or MAFIA as design aids in the development of rf cavities, we attempt here to elucidate various of the design parameters commonly dealt with in proton machines through the use of simple standing wave coaxial resonator expressions. In so doing, we treat only standing wave structures. Although low-impedance, moderately broad pass-band travelling wave accelerating systems are used in the CERN SPS, such systems are more commonly found in linacs, and they have not been used widely in large cyclic accelerators. Two appendices providing useful supporting material regarding relativistic particle dynamics and synchrotron motion in cyclic accelerators are added to supplement the text.

  1. Photonic Crystal Laser-Driven Accelerator Structures

    Energy Technology Data Exchange (ETDEWEB)

    Cowan, Benjamin M

    2007-08-22

    Laser-driven acceleration holds great promise for significantly improving accelerating gradient. However, scaling the conventional process of structure-based acceleration in vacuum down to optical wavelengths requires a substantially different kind of structure. We require an optical waveguide that (1) is constructed out of dielectric materials, (2) has transverse size on the order of a wavelength, and (3) supports a mode with speed-of-light phase velocity in vacuum. Photonic crystals---structures whose electromagnetic properties are spatially periodic---can meet these requirements. We discuss simulated photonic crystal accelerator structures and describe their properties. We begin with a class of two-dimensional structures which serves to illustrate the design considerations and trade-offs involved. We then present a three-dimensional structure, and describe its performance in terms of accelerating gradient and efficiency. We discuss particle beam dynamics in this structure, demonstrating a method for keeping a beam confined to the waveguide. We also discuss material and fabrication considerations. Since accelerating gradient is limited by optical damage to the structure, the damage threshold of the dielectric is a critical parameter. We experimentally measure the damage threshold of silicon for picosecond pulses in the infrared, and determine that our structure is capable of sustaining an accelerating gradient of 300 MV/m at 1550 nm. Finally, we discuss possibilities for manufacturing these structures using common microfabrication techniques.

  2. CLIC accelerator modules under construction at CERN

    CERN Multimedia

    Anna Pantelia

    2012-01-01

    The Compact LInear Collider (CLIC) study is dedicated to the design of an electron-positron (e- e+) linear accelerator, colliding particle beams at the energy of 3 TeV. The CLIC required luminosity can be reached with powerful particle beams (14 MW each) colliding with extremely small dimensions and high beam stability at the interaction point. The accelerated particle beams must have dimensions of 45 nm in the horizontal plane and 1 nm in the vertical plane. CLIC relies upon a novel two-beam acceleration concept in which the Radio Frequency (RF) power is extracted from a low energy but high-intensity particle beam, called Drive Beam (DB), and transferred to a parallel high energy accelerating particle beam, called Main Beam (MB). The extraction and transfer of the RF power is achieved by the Power Extraction and Transfer Structures (PETS) and the particle beam acceleration is achieved with high precision RF-Accelerating Structures (AS), operating at 11.9942 GHz with an accelerating gradient of 100 MV/m, whi...

  3. Centrifugal acceleration in the magnetotail lobes

    Directory of Open Access Journals (Sweden)

    H. Nilsson

    2010-02-01

    Full Text Available Combined Cluster EFW and EDI measurements have shown that cold ion outflow in the magnetospheric lobes dominates the hydrogen ion outflow from the Earth's atmosphere. The ions have too low kinetic energy to be measurable with particle instruments, at least for the typical spacecraft potential of a sunlit spacecraft in the tenuous lobe plasmas outside a few RE. The measurement technique yields both density and bulk velocity, which can be combined with magnetic field measurements to estimate the centrifugal acceleration experienced by these particles. We present a quantitative estimate of the centrifugal acceleration, and the velocity change with distance which we would expect due to centrifugal acceleration. It is found that the centrifugal acceleration is on average outward with an average value of about of 5 m s−2. This is small, but acting during long transport times and over long distances the cumulative effect is significant, while still consistent with the relatively low velocities estimated using the combination of EFW and EDI data. The centrifugal acceleration should accelerate any oxygen ions in the lobes to energies observable by particle spectrometers. The data set also put constraints on the effectiveness of any other acceleration mechanisms acting in the lobes, where the total velocity increase between 5 and 19 RE geocentric distance is less than 5 km s−1.

  4. Operational aspects of experimental accelerator physics

    Energy Technology Data Exchange (ETDEWEB)

    Decker, G.A.

    1995-07-01

    During the normal course of high energy storage ring operations, it is customary for blocks of time to be allotted to something called ``machine studies,`` or more simply, just ``studies.`` It is during these periods of time that observations and measurement of accelerator behavior are actually performed. Almost invariably these studies are performed in support of normal machine operations. The machine physicist is either attempting to improve machine performance, or more often trying to recover previously attained ``good`` operation, for example after an extended machine down period. For the latter activity, a good portion of machine studies time is usually devoted to ``beam tuning`` activities: those standard measurements and adjustments required to recover good operations. Before continuing, please note that this paper is not intended to be comprehensive. It is intended solely to reflect one accelerator physicist`s impressions as to what goes on in an accelerator control room. Many topics are discussed, some in more detail than others, and it is not the intention that the techniques described herein be applied verbatim to any existing accelerator. It is hoped,, however, that by reading through the various sections, scientists, including accelerator physicists, engineers, and accelerator beam users, will come to appreciate the types of operations that are required to make an accelerator work.

  5. Glutamic acid as anticancer agent: An overview

    National Research Council Canada - National Science Library

    Dutta, Satyajit; Ray, Supratim; Nagarajan, K

    2013-01-01

    The objective of the article is to highlight various roles of glutamic acid like endogenic anticancer agent, conjugates to anticancer agents, and derivatives of glutamic acid as possible anticancer agents...

  6. Advanced modeling of high intensity accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Ryne, R.D.; Habib, S.; Wangler, T.P.

    1998-11-01

    This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The goals of this project were three-fold: (1) to develop a new capability, based on high performance (parallel) computers, to perform large scale simulations of high intensity accelerators; (2) to apply this capability to modeling high intensity accelerators under design at LANL; and (3) to use this new capability to improve the understanding of the physics of intense charge particle beams, especially in regard to the issue of beam halo formation. All of these goals were met. In particular, the authors introduced split-operator methods as a powerful and efficient means to simulate intense beams in the presence of rapidly varying accelerating and focusing fields. They then applied these methods to develop scaleable, parallel beam dynamics codes for modeling intense beams in linacs, and in the process they implemented a new three-dimensional space charge algorithm. They also used the codes to study a number of beam dynamics issues related to the Accelerator Production of Tritium (APT) project, and in the process performed the largest simulations to date for any accelerator design project. Finally, they used the new modeling capability to provide direction and validation to beam physics studies, helping to identify beam mismatch as a major source of halo formation in high intensity accelerators. This LDRD project ultimately benefited not only LANL but also the US accelerator community since, by promoting expertise in high performance computing and advancing the state-of-the-art in accelerator simulation, its accomplishments helped lead to approval of a new DOE Grand Challenge in Computational Accelerator Physics.

  7. Mercury and autism: accelerating evidence?

    Science.gov (United States)

    Mutter, Joachim; Naumann, Johannes; Schneider, Rainer; Walach, Harald; Haley, Boyd

    2005-10-01

    The causes of autism and neurodevelopmental disorders are unknown. Genetic and environmental risk factors seem to be involved. Because of an observed increase in autism in the last decades, which parallels cumulative mercury exposure, it was proposed that autism may be in part caused by mercury. We review the evidence for this proposal. Several epidemiological studies failed to find a correlation between mercury exposure through thimerosal, a preservative used in vaccines, and the risk of autism. Recently, it was found that autistic children had a higher mercury exposure during pregnancy due to maternal dental amalgam and thimerosal-containing immunoglobulin shots. It was hypothesized that children with autism have a decreased detoxification capacity due to genetic polymorphism. In vitro, mercury and thimerosal in levels found several days after vaccination inhibit methionine synthetase (MS) by 50%. Normal function of MS is crucial in biochemical steps necessary for brain development, attention and production of glutathione, an important antioxidative and detoxifying agent. Repetitive doses of thimerosal leads to neurobehavioral deteriorations in autoimmune susceptible mice, increased oxidative stress and decreased intracellular levels of glutathione in vitro. Subsequently, autistic children have significantly decreased level of reduced glutathione. Promising treatments of autism involve detoxification of mercury, and supplementation of deficient metabolites.

  8. Inaccessibility in Multi-Agent Systems

    Science.gov (United States)

    2004-03-08

    Agent Manager takes care of creation, execution and removal of agents. – Service Manager . The Service Manager takes care of starting and stopping the...in Multi-Agent Systems 34 Agents Services Agent Manager Service Manager Container Core Message Transport Receiving Thread Incoming Queue Incoming Queue...the AgentContainer class contains public final variable TIMER (java.util.Timer). 6.5.6. Service Manager The Service Manager takes care of services

  9. Theory of the dielectric wakefield accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Mtingwa, S.K.

    1990-10-01

    The general theory for all angular modes m of the dielectric wakefield accelerator is reformulated. The expressions for the accelerating electric fields and transverse wake forces are written in terms of matrices, the zeros of one of which determine the excitation frequencies of the dielectric structure. In this scheme it is possible to obtain a maximum accelerating gradient of 2.0 megavolts per meter per nanoCoulomb of driver beam charge, for a driver beam of 0.7 millimeters rms bunch length. 29 refs., 5 figs.

  10. Ultra accelerated testing of PV module components

    Science.gov (United States)

    Pitts, J. R.; King, D. E.; Bingham, C.; Czanderna, A. W.

    1999-03-01

    Using concentrated natural sunlight at the NREL High Flux Solar Furnace, we have exposed several materials to acceleration factors of up to 400 times the normal outdoor UV exposure dose. This accelerated rate allows the exposure of materials such that a year of outdoor exposure can be simulated in about 5 hours. We have studied the solarization of cerium containing glass, the degradation of ethylene vinyl acetate laminated between borosilicate glass, and the yellowing of standard polystyrene test coupons. The first two candidates are of interest to the photovoltaics (PV) program, and the last candidate material is a widely used dosimeter for ultra violet (UV) exposure in accelerated weathering chambers.

  11. Heavy Ion Fusion Accelerator Research (HIFAR)

    Energy Technology Data Exchange (ETDEWEB)

    1991-04-01

    This report discusses the following topics: emittance variations in current-amplifying ion induction lina; transverse emittance studies of an induction accelerator of heavy ions; drift compression experiments on MBE-4 and related emittance; low emittance uniform- density C{sub s}+ sources for heavy ion fusion accelerator studies; survey of alignment of MBE-4; time-of-flight dependence on the MBE-4 quadrupole voltage; high order calculation of the multiple content of three dimensional electrostatic geometries; an induction linac injector for scaled experiments; induction accelerator test module for HIF; longitudinal instability in HIF beams; and analysis of resonant longitudinal instability in a heavy ion induction linac.

  12. Ultra Accelerated Testing of PV Module Components

    Energy Technology Data Exchange (ETDEWEB)

    Pitts, J. R.; King, D. E.; Bingham, C.; Czanderna, A. W.

    1998-10-28

    Using concentrated natural sunlight at the NREL High Flux Solar Furnace, we have exposed several materials to acceleration factors of up to 400 times the normal outdoor UV exposure dose. This accelerated rate allows the exposure of materials such that a year of outdoor exposure can be simulated in about 5 hours. We have studied the solarization of cerium containing glass, the degradation of ethylene vinyl acetate laminated between borosilicate glass, and the yellowing of standard polystyrene test coupons. The first two candidates are of interest to the photovoltaics (PV) program, and the last candidate material is a widely used dosimeter for ultra violet (UV) exposure in accelerated weathering chambers

  13. Measurement and correction of accelerator optics

    Energy Technology Data Exchange (ETDEWEB)

    Zimmerman, F.

    1998-06-01

    This report reviews procedures and techniques for measuring, correcting and controlling various optics parameters of an accelerator, including the betatron tune, beta function, betatron coupling, dispersion, chromaticity, momentum compaction factor, and beam orbit. The techniques described are not only indispensable for the basic set-up of an accelerator, but in addition the same methods can be used to study more esoteric questions as, for instance, dynamic aperture limitations or wakefield effects. The different procedures are illustrated by examples from several accelerators, storage rings, as well as linacs and transport lines.

  14. Accelerated rotation with orbital angular momentum modes

    CSIR Research Space (South Africa)

    Schulze, C

    2015-01-01

    Full Text Available ) Accelerated rotation with orbital angular momentum modes Christian Schulze,1 Filippus S. Roux,2 Angela Dudley,2 Ronald Rop,3 Michael Duparre´,1 and Andrew Forbes2,4,* 1Institute of Applied Optics, Friedrich Schiller University, Fro¨belstieg 1, 07743 Jena... from the transverse acceleration discussed before. We tailor our “twisted light” (fields carrying orbital angular momentum) to have a nonlinear phase variation with azimuthal angle, which we show is the building block for angular accelerating light...

  15. Fermi Acceleration in driven relativistic billiards

    Energy Technology Data Exchange (ETDEWEB)

    Pinto, Rafael S., E-mail: rsoaresp@ifi.unicamp.br [Instituto de Fisica ' Gleb Wataghin' , Universidade Estadual de Campinas, 13083-970, Campinas, SP (Brazil); Letelier, Patricio S. [Departamento de Matematica Aplicada, Instituto de Matematica, Estatistica e Computacao Cientifica, Universidade Estadual de Campinas, 13083-859, Campinas, SP (Brazil)

    2011-08-29

    We show numerical experiments of driven billiards using special relativity. We have the remarkable fact that for the relativistic driven circular and annular concentric billiards, depending on initial conditions and parameters, we observe Fermi Acceleration, absent in the Newtonian case. The velocity for these cases tends to the speed of light very quickly. We find that for the annular eccentric billiard the initial velocity grows for a much longer time than the concentric annular billiard until it asymptotically reach c. -- Highlights: → Fermi Acceleration is studied for relativistic driven billiards. → We studied regular and chaotic billiards with different parameters. → Fermi Acceleration is present even for static regular billiards.

  16. Two-dimensional photonic crystal accelerator structures

    Directory of Open Access Journals (Sweden)

    Benjamin M. Cowan

    2003-10-01

    Full Text Available Photonic crystals provide a method of confining a synchronous speed-of-light mode in an all-dielectric structure, likely a necessary feature in any optical accelerator. We explore computationally a class of photonic crystal structures with translational symmetry in a direction transverse to the electron beam. We demonstrate synchronous waveguide modes and discuss relevant parameters of such modes. We then explore how accelerator parameters vary as the geometry of the structure is changed and consider trade-offs inherent in the design of an accelerator of this type.

  17. Accelerating video carving from unallocated space

    Science.gov (United States)

    Kalva, Hari; Parikh, Anish; Srinivasan, Avinash

    2013-03-01

    Video carving has become an essential tool in digital forensics. Video carving enables recovery of deleted video files from hard disks. Processing data to extract videos is a computationally intensive task. In this paper we present two methods to accelerate video carving: a method to accelerate fragment extraction, and a method to accelerate combining of these fragments into video segments. Simulation results show that complexity of video fragment extraction can be reduced by as much as 75% with minimal impact on the videos recovered.

  18. Hybrid Simulations of Particle Acceleration at Shocks

    Energy Technology Data Exchange (ETDEWEB)

    Caprioli, Damiano

    2014-11-15

    We present the results of large hybrid (kinetic ions – fluid electrons) simulations of particle acceleration at non-relativistic collisionless shocks. Ion acceleration efficiency and magnetic field amplification are investigated in detail as a function of shock inclination and strength, and compared with predictions of diffusive shock acceleration theory, for shocks with Mach number up to 100. Moreover, we discuss the relative importance of resonant and Bell's instability in the shock precursor, and show that diffusion in the self-generated turbulence can be effectively parametrized as Bohm diffusion in the amplified magnetic field.

  19. Lessons from the Bevatron Accelerator Demolition - 12191

    Energy Technology Data Exchange (ETDEWEB)

    Harkins, Joseph [Lawrence Berkeley National Laboratory, Berkeley, California, 94720 (United States); Cronin, Robert [CH2M HILL, Englewood, Colorado, 80112 (United States)

    2012-07-01

    The Bevatron accelerator at Lawrence Berkeley National Laboratory is the first DOE accelerator to be demolished. While there are many lessons learned from its demolition, this paper focuses on the following lessons learned that may be useful for other D and D projects: bounding project scope to ensure success, hazards mapping for focused characterization and remediation, establishing radiological evaluation criteria, and forecasting activation products. With D and D of many DOE accelerators likely to occur in the near future, these lessons learned should be considered in planning those projects. These lessons learned are likely to be applicable to other D and D projects as well. (authors)

  20. Accelerating Dense Linear Algebra on the GPU

    DEFF Research Database (Denmark)

    Sørensen, Hans Henrik Brandenborg

    GPUs have already become an integral part of high performance scientific computing, since they offer dedicated parallel hardware that can potentially accelerate the execution of many scientific applications. In this talk, I will consider the automatic performance acceleration of dense vector...... and matrix-vector operations on GPUs. Such operations form the backbone of level 1 and level 2 routines in the Basic Linear Algebra Subroutines (BLAS) library and are therefore of great importance in many scientific applications. The target hardware is the most recent NVIDIA Tesla 20-series (Fermi...... architecture). Most of the techniques I discuss for accelerating dense linear algebra are applicable to memory-bound GPU algorithms in general....

  1. TWO-CHANNEL DIELECTRIC WAKE FIELD ACCELERATOR

    Energy Technology Data Exchange (ETDEWEB)

    Jay L. Hirshfield

    2012-05-30

    Experimental results are reported for test beam acceleration and deflection in a two-channel, cm-scale, rectangular dielectric-lined wakefield accelerator structure energized by a 14-MeV drive beam. The dominant waveguide mode of the structure is at {approx}30 GHz, and the structure is configured to exhibit a high transformer ratio ({approx}12:1). Accelerated bunches in the narrow secondary channel of the structure are continuously energized via Cherenkov radiation that is emitted by a drive bunch moving in the wider primary channel. Observed energy gains and losses, transverse deflections, and changes in the test bunch charge distribution compare favorably with predictions of theory.

  2. Community Health Agents and the meanings of "being an agent"

    OpenAIRE

    Viviane Milan Pupin; Cármen Lúcia Cardoso

    2008-01-01

    O Programa Saúde da Família constitui-se enquanto estratégia de mudança do modelo assistencial. O artigo apresenta os resultados de uma pesquisa qualitativa sobre os sentidos de "ser agente" produzidos, por meio de entrevistas abertas, com Agentes Comunitários de Saúde que trabalham nos cinco Núcleos de Saúde da Família da cidade de Ribeirão Preto - São Paulo, vinculados à Faculdade de Medicina de Ribeirão Preto - USP. As entrevistas foram gravadas e transcritas na íntegra e analisadas segund...

  3. One-Dimensional Model of the Pulsar Accelerator

    OpenAIRE

    TSUKAMOTO, Kaoru; SHIBATA, Shinpei

    1991-01-01

    We construct an one-dimensional model of the accelerating region of the pulsar magnetosphere. The pair-creation-limited voltage of accelerator is obtained as fanctions of the location of the accelerator.

  4. RF accelerating unit installed in the PSB

    CERN Multimedia

    CERN PhotoLab

    1972-01-01

    RF accelerating unit installed in the PSB ring between two bending magnets. Cool air from a heat exchanger is injected into the four cavities from the central feeder and the hot air recirculated via the lateral ducts.

  5. Machine Protection: Availability for Particle Accelerators

    CERN Document Server

    Apollonio, Andrea; Schmidt, Ruediger

    2015-03-16

    Machine availability is a key indicator for the performance of the next generation of particle accelerators. Availability requirements need to be carefully considered during the design phase to achieve challenging objectives in different fields, as e.g. particle physics and material science. For existing and future High-Power facilities, such as ESS (European Spallation Source) and HL-LHC (High-Luminosity LHC), operation with unprecedented beam power requires highly dependable Machine Protection Systems (MPS) to avoid any damage-induced downtime. Due to the high complexity of accelerator systems, finding the optimal balance between equipment safety and accelerator availability is challenging. The MPS architecture, as well as the choice of electronic components, have a large influence on the achievable level of availability. In this thesis novel methods to address the availability of accelerators and their protection systems are presented. Examples of studies related to dependable MPS architectures are given i...

  6. Accelerated Aging in Electrolytic Capacitors for Prognostics

    Data.gov (United States)

    National Aeronautics and Space Administration — The focus of this work is the analysis of different degradation phenomena based on thermal overstress and electrical overstress accelerated aging systems and the use...

  7. Pulsed power accelerators for particle beam fusion

    Science.gov (United States)

    Martin, T. H.; Barr, G. W.; Vandevender, J. P.; White, R. A.; Johnson, D. L.

    1980-05-01

    Sandia National Laboratories is completing the construction phase of the Particle Beam Fusion Accelerator-1 (PBFA-1). Testing of the 36 module, 30 TW, 1 MJ output accelerator is in the initial stages. The 4 MJ, PBFA Marx generator provided 3.6 MA into water-copper sulfate load resistors with a spread from first to last Marx firing between 15 to 25 ns and an output power of 5.7 TW. This accelerator is a modular, lower voltage, pulsed power device that is capable of scaling to power levels exceeding 100 TW. The elements of the PBFA technology and their integration into an accelerator system for particle beam fusion is discussed.

  8. Accelerator Sector - together we're stronger

    CERN Multimedia

    2002-01-01

    From 1 January onwards, the Accelerator Sector will be reorganised into two new divisions AB and AT. We talked to the leaders of these two divisions, Steve Myers and Philippe Lebrun, about this reorganisation.

  9. NIH/NSF accelerate biomedical research innovations

    Science.gov (United States)

    A collaboration between the National Science Foundation and the National Institutes of Health will give NIH-funded researchers training to help them evaluate their scientific discoveries for commercial potential, with the aim of accelerating biomedical in

  10. Radiation-resistant fibre for particle accelerator

    CERN Multimedia

    2007-01-01

    "Radiation-resistant optical fibre is being used by CERN, the European Laboratory for Particle Physics, in the world's largest particle accelerator, the Large Hadron Collider (LHC) near Geneva." (1 page)

  11. AXEL-2016: Introduction to Particle Accelerators

    CERN Document Server

    2016-01-01

    AXEL-2016 is the latest in a yearly lecture series on particle accelerators given at CERN within the framework of the 2016 Technical Training Programme. As part of the BE department's Operation group’s shutdown lecture series, this general accelerator physics module has been offered since 2003 as a joint venture between the BE department and the Technical Training team and is open to the wider CERN community.    The lecturer is Rende Steerenberg, deputy leader of the Operation group and PS section leader. Programme: basic mathematics; transverse optics; lattice calculations; resonances; longitudinal motion; transfer lines, injection and ejection; longitudinal and transverse beam instabilities; colliders. A detailed programme is available on the AXEL-2016 webpage. Target audience: designed for technicians who are operating an accelerator or whose work is closely linked to accelerators, but also open to technicians, engineers and physicists interested i...

  12. Cognitive Acceleration through Science Education: Alternative Perspectives.

    Science.gov (United States)

    Jones, Marion; Gott, Richard

    1998-01-01

    Reviews evidence of the effectiveness of a scheme resulting from CASE (cognitive acceleration through science education) research. Focuses on the effectiveness of the scheme in raising standards in science. Contains 16 references. (DDR)

  13. Acceleration feature points of unsteady shear flows

    CERN Document Server

    Kasten, Jens; Hotz, Ingrid; Hege, Hans-Christian; Noack, Bernd R; Daviller, Guillaume; Morzynski, Marek

    2014-01-01

    In this paper, we propose a novel framework to extract features such as vortex cores and saddle points in two-dimensional unsteady flows. This feature extraction strategy generalizes critical points of snapshot topology in a Galilean-invariant manner, allows to prioritize features according to their strength and longevity, enables to track the temporal evolution of features, is robust against noise and has no subjective parameters. These characteristics are realized via several constitutive elements. First, acceleration is employed as a feature identifier following Goto and Vassilicos (2006), thus ensuring Galilean invariance. Second, the acceleration magnitude is used as basis for a mathematically well-developed scalar field topology. The minima of this field are called acceleration feature points, a superset of the acceleration zeros. These points are discriminated into vortices and saddle points depending the spectral properties of the velocity Jacobian. Third, all operations are based on discrete topology...

  14. Anderson Acceleration for Fixed-Point Iterations

    Energy Technology Data Exchange (ETDEWEB)

    Walker, Homer F. [Worcester Polytechnic Institute, MA (United States)

    2015-08-31

    The purpose of this grant was to support research on acceleration methods for fixed-point iterations, with applications to computational frameworks and simulation problems that are of interest to DOE.

  15. The world's largest proton accelerator takes shape

    CERN Document Server

    Persson, L

    1974-01-01

    The European Organization for Nuclear Research, Established in Geneva, decided in February 1971 to build such an accelerator at a cost of 1150 million Swiss francs over an 8-year period. In something over three years the number of persons directly or indirectly employed by this organization (CERN) has risen to around 4700, including around 80 from the Swedish universities of Gothernburg, Lund, and Stockholm, and from research establishments in Uppsala and Studsvik. The project will provide for a maximum proton energy of 400 GeV, an intensity of 10/sup 13/ protons per pulse, and an accelerator step frequency of 200 MHz. The accelerator is located 40 m underground in a circular tunnel with a circumference of 6.9 km. A large assembly hall, laboratory buildings, and research departments were taken into operation in 1973. More than half the accelerator tunnel is already bored out and the steel transport tunnels are blasted out to the extent of 80%.

  16. Identifying regional opportunities for accelerated timber managemnet

    Science.gov (United States)

    David A. Gansner; Joseph E. Barnard; Samuel F. Gingrich; Samuel F. Gingrich

    1973-01-01

    Describes a procedure for identifying regional opportunities for accelerated timber management and demonstrates its application. Results provide a basis for rational choices among alternative management strategies and permit meaningful micro- and macro-evaluations of treatment response.

  17. Accelerating Climate Simulations Through Hybrid Computing

    Science.gov (United States)

    Zhou, Shujia; Sinno, Scott; Cruz, Carlos; Purcell, Mark

    2009-01-01

    Unconventional multi-core processors (e.g., IBM Cell B/E and NYIDIDA GPU) have emerged as accelerators in climate simulation. However, climate models typically run on parallel computers with conventional processors (e.g., Intel and AMD) using MPI. Connecting accelerators to this architecture efficiently and easily becomes a critical issue. When using MPI for connection, we identified two challenges: (1) identical MPI implementation is required in both systems, and; (2) existing MPI code must be modified to accommodate the accelerators. In response, we have extended and deployed IBM Dynamic Application Virtualization (DAV) in a hybrid computing prototype system (one blade with two Intel quad-core processors, two IBM QS22 Cell blades, connected with Infiniband), allowing for seamlessly offloading compute-intensive functions to remote, heterogeneous accelerators in a scalable, load-balanced manner. Currently, a climate solar radiation model running with multiple MPI processes has been offloaded to multiple Cell blades with approx.10% network overhead.

  18. Sequential injection gas guns for accelerating projectiles

    Science.gov (United States)

    Lacy, Jeffrey M [Idaho Falls, ID; Chu, Henry S [Idaho Falls, ID; Novascone, Stephen R [Idaho Falls, ID

    2011-11-15

    Gas guns and methods for accelerating projectiles through such gas guns are described. More particularly, gas guns having a first injection port located proximate a breech end of a barrel and a second injection port located longitudinally between the first injection port and a muzzle end of the barrel are described. Additionally, modular gas guns that include a plurality of modules are described, wherein each module may include a barrel segment having one or more longitudinally spaced injection ports. Also, methods of accelerating a projectile through a gas gun, such as injecting a first pressurized gas into a barrel through a first injection port to accelerate the projectile and propel the projectile down the barrel past a second injection port and injecting a second pressurized gas into the barrel through the second injection port after passage of the projectile and to further accelerate the projectile are described.

  19. Kinetic Simulations of Particle Acceleration at Shocks

    Energy Technology Data Exchange (ETDEWEB)

    Caprioli, Damiano [Princeton University; Guo, Fan [Los Alamos National Laboratory

    2015-07-16

    Collisionless shocks are mediated by collective electromagnetic interactions and are sources of non-thermal particles and emission. The full particle-in-cell approach and a hybrid approach are sketched, simulations of collisionless shocks are shown using a multicolor presentation. Results for SN 1006, a case involving ion acceleration and B field amplification where the shock is parallel, are shown. Electron acceleration takes place in planetary bow shocks and galaxy clusters. It is concluded that acceleration at shocks can be efficient: >15%; CRs amplify B field via streaming instability; ion DSA is efficient at parallel, strong shocks; ions are injected via reflection and shock drift acceleration; and electron DSA is efficient at oblique shocks.

  20. Global particle accelerator gets the big chill

    CERN Multimedia

    Sherriff, Lucy

    2004-01-01

    Scientists at an international symposium in Beijing have recommended that a new global particle accelerator should be based on "cold" or superconducting technology, bringing the construction of the multi-billion dollar facility one step closer to reality (½ page)

  1. Solid oxide materials research accelerated electrochemical testing

    Energy Technology Data Exchange (ETDEWEB)

    Windisch, C.; Arey, B.

    1995-08-01

    The objectives of this work were to develop methods for accelerated testing of cathode materials for solid oxide fuel cells under selected operating conditions. The methods would be used to evaluate the performance of LSM cathode material.

  2. RF superconductivity for accelerators. 2. ed.

    Energy Technology Data Exchange (ETDEWEB)

    Padamsee, H. [Cornell Univ., Ithaca, NY (United States). Lab. of Nuclear Studies; Knobloch, J. [BESSY GmbH, Berlin (Germany); Hays, T. [Cosmic Consulting, Gore, VA (United States)

    2008-07-01

    This book introduces some of the key ideas of RF Superconductivity by using a pedagogic approach, and presents a comprehensive overview of the field. It is divided into four parts. The first part introduces the basic concepts of microwave cavities for particle acceleration. The second part is devoted to the observed behavior of superconducting cavities. In the third part, general issues connected with beam-cavity interaction and related issues for critical components are covered. The final part discusses applications of superconducting cavities to frontier accelerators of the future, drawing heavily on examples that are in their most advanced stage. Each part of the book ends in a problems section to illustrate and amplify text material as well as to draw on example applications of superconducting cavities to existing and future accelerators. From the Contents: - Basics - Performance of Superconducting Cavities - Couplers and Tuners - Frontier Accelerators. (orig.)

  3. The crystal acceleration effect for cold neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Braginetz, Yu. P., E-mail: aiver@pnpi.spb.ru [Petersburg Nuclear Physics Institute NRC KI (Russian Federation); Berdnikov, Ya. A. [Peter the Great St. Petersburg Polytechnic University (Russian Federation); Fedorov, V. V., E-mail: vfedorov@pnpi.spb.ru; Kuznetsov, I. A.; Lasitsa, M. V.; Semenikhin, S. Yu., E-mail: ssy@pnpi.spb.ru; Vezhlev, E. O.; Voronin, V. V., E-mail: vvv@pnpi.spb.ru [Petersburg Nuclear Physics Institute NRC KI (Russian Federation)

    2017-01-15

    A new mechanism of neutron acceleration is discussed and studied experimentally in detail for cold neutrons passing through the accelerated perfect crystal with the energies close to the Bragg one. The effect arises due to the following reason. The crystal refraction index (neutron-crystal interaction potential) for neutron in the vicinity of the Bragg resonance sharply depends on the parameter of deviation from the exact Bragg condition, i.e. on the crystal-neutron relative velocity. Therefore the neutrons enter into accelerated crystal with one neutron-crystal interaction potential and exit with the other. Neutron kinetic energy cannot vary inside the crystal due to its homogeneity. So after passage through such a crystal neutrons will be accelerated or decelerated because of the different energy change at the entrance and exit crystal boundaries.

  4. Reviews of accelerator science and technology

    CERN Document Server

    Chou, Weiren

    2008-01-01

    Particle accelerators are a major invention of the 20th century. In the last eight decades, they have evolved enormously and have fundamentally changed the way we live, think and work. Accelerators are the most powerful microscopes for viewing the tiniest inner structure of cells, genes, molecules, atoms and their constituents such as protons, neutrons, electrons, neutrinos and quarks. This opens up a whole new world for materials science, chemistry and molecular biology.Accelerators with megawatt beam power may ultimately solve a critical problem faced by our society, namely, the treatment of nuclear waste and the supply of an alternative type of energy. There are also tens of thousands of small accelerators all over the world. They are used every day for medical imaging, cancer therapy, radioisotope production, high-density chip-making, mass spectrometry, cargo x-ray/gamma-ray imaging, detection of explosives and illicit drugs, and weapons. This volume provides a comprehensive review of this driving and fas...

  5. Special radiation protection aspects of medical accelerators

    CERN Document Server

    Silari, Marco

    2001-01-01

    Radiation protection aspects relevant to medical accelerators are discussed. An overview is first given of general safety requirements. Next. shielding and labyrinth design are discussed in some detail for the various types of accelerators, devoting more attention to hadron machines as they are far less conventional than electron linear accelerators. Some specific aspects related to patient protection are also addressed. Finally, induced radioactivity in accelerator components and shielding walls is briefly discussed. Three classes of machines are considered: (1) medical electron linacs for 'conventional' radiation therapy. (2) low energy cyclotrons for production of radionuclides mainly for medical diagnostics and (3) medium energy cyclotrons and synchrotrons for advanced radiation therapy with protons or light ion beams (hadron therapy). (51 refs).

  6. Solid oxide materials research accelerated electrochemical testing

    Energy Technology Data Exchange (ETDEWEB)

    Armstrong, T.R.; Windisch, C.; Arey, B.

    1995-12-31

    The objectives of this work were to develop methods for accelerated testing of cathode material for solid oxide fuel cells under selected operating conditions. The methods would be used to evaluate the performance of LSM cathode material.

  7. Laser acceleration... now with added fibre

    CERN Multimedia

    Katarina Anthony

    2012-01-01

    Laser acceleration technology is plagued by two main issues: efficiency and repetition rates. In other words, lasers consume too much power and cannot sustain accelerating particles long enough to produce collisions. ICAN, a new EU-funded project, is examining how fibre lasers may help physicists tackle these issues.   A diode-pumped fibre laser. (Image courtesy of Laser Zentrum Hannover.) The International Coherent Amplification Network (ICAN) is studying the potential of lasers for collision physics. CERN is a beneficiary of the project and will collaborate with 15 other institutes from around the world, including KEK in Japan, Fermilab in the USA, and DESY in Germany. “The network is looking into existing fibre laser technology, which we believe has fantastic potential for accelerators,” says Gerard Mourou, ICAN co-ordinator at the École Polytechnique in France. “The hope is to make laser acceleration competitive with traditional radio-fre...

  8. The evolution of high energy accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Courant, E.D.

    1989-10-01

    In this lecture I would like to trace how high energy particle accelerators have grown from tools used for esoteric small-scale experiments to gigantic projects being hotly debated in Congress as well as in the scientific community.

  9. Global Earthquake Hazard Distribution - Peak Ground Acceleration

    Data.gov (United States)

    National Aeronautics and Space Administration — Global Earthquake Hazard Distribution-peak ground acceleration is a 2.5 minute grid of global earthquake hazards developed using Global Seismic Hazard Program...

  10. Clearance of materials from accelerator facilities

    Directory of Open Access Journals (Sweden)

    Rokni Sayed H.

    2017-01-01

    Full Text Available A new Technical Standard that supports the clearance of materials and equipment (personal property from U.S. Department of Energy (DOE accelerator facilities has been developed. The Standard focuses on personal property that has the potential to be radiologically impacted by accelerator operations. It addresses material clearance programs and protocols for off-site releases without restriction on use. Common metals with potential volumetric activation are of main interest with technical bases provided in Appendices of the Standard. The clearance protocols in the Standard include three elements: 1 clearance criteria, 2 process knowledge, and 3 measurement methods. This paper presents the technical aspects of the new Standard, discusses operational experience gained in clearance of materials and equipment from several accelerator facilities at SLAC and examples as to how this Standard can be applied to benefit the entirety of the DOE Accelerator Complex.

  11. Global Earthquake Hazard Distribution - Peak Ground Acceleration

    Data.gov (United States)

    National Aeronautics and Space Administration — Global Earthquake Hazard Distribution-Peak Ground Acceleration is a 2.5 by 2.5 minute grid of global earthquake hazards developed using Global Seismic Hazard Program...

  12. Lauch of CERN particle accelerator delayed

    CERN Multimedia

    2007-01-01

    "Scientists seeking to uncover the secrets of the universe will have to wait a little longer after the CERN laboratory inSwitzerland yesterday confirmed a delay in tests of its massive new particle accelerator." (1 page)

  13. Energy efficiency of laser driven, structure based accelerators

    Directory of Open Access Journals (Sweden)

    R. H. Siemann

    2004-06-01

    Full Text Available The acceleration efficiency of a laser driven linear accelerator is analyzed. The laser power, loss factor, and impedances determine the maximum charge that can be accelerated and the efficiency of that acceleration. The accelerator structure can be incorporated into a laser cavity. The equation for the resultant laser pulse is derived and analyzed. A specific example is presented, and the steady-state laser pulse shapes, acceleration efficiency, and average unloaded gradient are calculated.

  14. Agent Based Individual Traffic Guidance

    DEFF Research Database (Denmark)

    Wanscher, Jørgen

    This thesis investigates the possibilities in applying Operations Research (OR) to autonomous vehicular traffic. The explicit difference to most other research today is that we presume that an agent is present in every vehicle - hence Agent Based Individual Traffic guidance (ABIT). The next...... evolutionary step for the in-vehicle route planners is the introduction of two-way communication. We presume that the agent is capable of exactly this. Based on this presumption we discuss the possibilities and define a taxonomy and use this to discuss the ABIT system. Based on a set of scenarios we conclude...... of the project were not previously considered. We define a special inseparable cost function and develop a solution complex capable of using this cost function. In relation to calibration and estimation of statistical models used for dynamic route guidance we worked with generating random number sequences...

  15. Agent review phase one report.

    Energy Technology Data Exchange (ETDEWEB)

    Zubelewicz, Alex Tadeusz; Davis, Christopher Edward; Bauer, Travis LaDell

    2009-12-01

    This report summarizes the findings for phase one of the agent review and discusses the review methods and results. The phase one review identified a short list of agent systems that would prove most useful in the service architecture of an information management, analysis, and retrieval system. Reviewers evaluated open-source and commercial multi-agent systems and scored them based upon viability, uniqueness, ease of development, ease of deployment, and ease of integration with other products. Based on these criteria, reviewers identified the ten most appropriate systems. The report also mentions several systems that reviewers deemed noteworthy for the ideas they implement, even if those systems are not the best choices for information management purposes.

  16. Children as digital rights agents

    DEFF Research Database (Denmark)

    Stald, Gitte Bang

    2016-01-01

    This paper looks at children’s involvement and contribution to internet safety policy. In many respects, the research perspective on children and young people has also seen a shift towards the child as agent, as citizen (Livingstone 2002, 2009; Dahlgren 2007). With increasing attention given...... to children’s communication rights there is an acknowledgement that children’s voices should be heard in all matters that affect them (Hamelink 2008). We still, however, primarily discuss how adults could and should take responsibility in guarding children and young people from risk and harm, and what...... 2007). The paper presents a model for analyzing the intersecting levels of children as agents in relation to digital risks and rights: Children as peer-to-peer agents. Children provide mutual practical guidance; experience sharing; advice. re. to risk and harm. Children as advocates/ politicians...

  17. Dopamine agents for hepatic encephalopathy

    DEFF Research Database (Denmark)

    Junker, Anders Ellekær; Als-Nielsen, Bodil; Gluud, Christian

    2014-01-01

    BACKGROUND: Patients with hepatic encephalopathy may present with extrapyramidal symptoms and changes in basal ganglia. These changes are similar to those seen in patients with Parkinson's disease. Dopamine agents (such as bromocriptine and levodopa, used for patients with Parkinson's disease) have...... therefore been assessed as a potential treatment for patients with hepatic encephalopathy. OBJECTIVES: To evaluate the beneficial and harmful effects of dopamine agents versus placebo or no intervention for patients with hepatic encephalopathy. SEARCH METHODS: Trials were identified through the Cochrane...... of the trials followed participants after the end of treatment. Only one trial reported adequate bias control; the remaining four trials were considered to have high risk of bias. Random-effects model meta-analyses showed that dopamine agents had no beneficial or detrimental effect on hepatic encephalopathy...

  18. Learning Agents in Automated Negotiations

    Science.gov (United States)

    Chandrashekhar, Hemalatha; Bhasker, Bharat

    In bilateral multi-issue negotiations involving two-sided information uncertainty, selfish agents participating in a distributed search of the solution space need to learn the opponent’s preferences from the on-going negotiation interactions and utilize such knowledge to construct future proposals in order to hope to arrive at efficient outcomes. Besides, negotiation support systems that inhibit strategic misrepresentation of information need to be in place in order to assist the protagonists to obtain truly efficient solutions. To this end, this work suggests an automated negotiation procedure that while protecting the information privacy of the participating agents encourages truthful revelation of information through successive proposals. Further we present an algorithm for proposal construction in the case of two continuous issues. When both the negotiating agents implement the algorithm the negotiation trace shall be confined to the Pareto frontier. The Pareto-optimal deal close to the Nash solution shall be located whenever such a deal exists.

  19. Oak Ridge 25-MV tandem accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Ziegler, N.F.; Richardson, E.G.; Mann, J.E.; Juras, R.C.; Jones, C.M.; Biggerstaff, J.A.; Benjamin, J.A.

    1981-01-01

    A new heavy-ion accelerator facility is nearing completion at the Oak Ridge National Laboratory. This paper presents a brief description of the scope and status of this project and a discussion of some aspects of the first operational experience with the 25 MV tandem accelerator which is being provided by the National Electrostatics Corporation (NEC) as a major component of the first phase of the facility.

  20. Accelerator development in India for ADS programme

    Indian Academy of Sciences (India)

    Abstract. At BARC, development of a Low Energy High Intensity Proton Accelerator. (LEHIPA), as front-end injector of the 1 GeV accelerator for the ADS programme, has been initiated. The major components of LEHIPA (20 MeV, 30 mA) are a 50 keV ECR ion source, a 3 MeV Radio Frequency Quadrupole (RFQ) and a 20 ...