WorldWideScience

Sample records for modeling system gems

  1. The GEM Silicon Tracking System

    International Nuclear Information System (INIS)

    Mills, G.B.

    1993-01-01

    The GEM Collaboration has produced a baseline design for the GEM detector. The baseline design of the GEM Silicon Tracking System (STS) is discussed in this article. Mechanical and electrical engineering progress on the GEM STS is described. Results from simulations of detector performance and the implications on engineering issues are described

  2. GEM System: automatic prototyping of cell-wide metabolic pathway models from genomes

    Directory of Open Access Journals (Sweden)

    Nakayama Yoichi

    2006-03-01

    Full Text Available Abstract Background Successful realization of a "systems biology" approach to analyzing cells is a grand challenge for our understanding of life. However, current modeling approaches to cell simulation are labor-intensive, manual affairs, and therefore constitute a major bottleneck in the evolution of computational cell biology. Results We developed the Genome-based Modeling (GEM System for the purpose of automatically prototyping simulation models of cell-wide metabolic pathways from genome sequences and other public biological information. Models generated by the GEM System include an entire Escherichia coli metabolism model comprising 968 reactions of 1195 metabolites, achieving 100% coverage when compared with the KEGG database, 92.38% with the EcoCyc database, and 95.06% with iJR904 genome-scale model. Conclusion The GEM System prototypes qualitative models to reduce the labor-intensive tasks required for systems biology research. Models of over 90 bacterial genomes are available at our web site.

  3. Design and implementation of the infrastructure of HadGEM3: the next-generation Met Office climate modelling system

    Directory of Open Access Journals (Sweden)

    H. T. Hewitt

    2011-04-01

    Full Text Available This paper describes the development of a technically robust climate modelling system, HadGEM3, which couples the Met Office Unified Model atmosphere component, the NEMO ocean model and the Los Alamos sea ice model (CICE using the OASIS coupler. Details of the coupling and technical solutions of the physical model (HadGEM3-AO are documented, in addition to a description of the configurations of the individual submodels. The paper demonstrates that the implementation of the model has resulted in accurate conservation of heat and freshwater across the model components. The model performance in early versions of this climate model is briefly described to demonstrate that the results are scientifically credible. HadGEM3-AO is the basis for a number of modelling efforts outside of the Met Office, both within the UK and internationally. This documentation of the HadGEM3-AO system provides a detailed reference for developers of HadGEM3-based climate configurations.

  4. Simulation of the CMS GEM System

    CERN Document Server

    Sharma, Archie

    2015-01-01

    The new GE1/1 system of Gas Electron Multipiers (GEM) is going to be installed in the CMS detector in the forward region with $\\eta$ between 1.6 and 2.2 after the second long LHC shutdown. 36 super-chambers are planned to be installed in order to ensure the redundancy and robustness of the muon system in high-luminosity conditions at the LHC. A further extension to the GEM system is also considered. The simulation of the entire GEM system integrated in the common CMS reconstruction chain is a necessary part of the performed Monte Carlo studies. A dedicated parametric model based on the exhaustive standalone MC studies and experimental test beam results has been developed in order to simulate the response of the GEM system. The simulated digital readout signals are used to build the reconstructed hits in the detector planes. They have been included in the common CMS muon reconstruction algorithms. This contribution will present the developed simulation model and the importance of the gem system for the improve...

  5. GEM - The Global Earthquake Model

    Science.gov (United States)

    Smolka, A.

    2009-04-01

    Over 500,000 people died in the last decade due to earthquakes and tsunamis, mostly in the developing world, where the risk is increasing due to rapid population growth. In many seismic regions, no hazard and risk models exist, and even where models do exist, they are intelligible only by experts, or available only for commercial purposes. The Global Earthquake Model (GEM) answers the need for an openly accessible risk management tool. GEM is an internationally sanctioned public private partnership initiated by the Organisation for Economic Cooperation and Development (OECD) which will establish an authoritative standard for calculating and communicating earthquake hazard and risk, and will be designed to serve as the critical instrument to support decisions and actions that reduce earthquake losses worldwide. GEM will integrate developments on the forefront of scientific and engineering knowledge of earthquakes, at global, regional and local scale. The work is organized in three modules: hazard, risk, and socio-economic impact. The hazard module calculates probabilities of earthquake occurrence and resulting shaking at any given location. The risk module calculates fatalities, injuries, and damage based on expected shaking, building vulnerability, and the distribution of population and of exposed values and facilities. The socio-economic impact module delivers tools for making educated decisions to mitigate and manage risk. GEM will be a versatile online tool, with open source code and a map-based graphical interface. The underlying data will be open wherever possible, and its modular input and output will be adapted to multiple user groups: scientists and engineers, risk managers and decision makers in the public and private sectors, and the public-at- large. GEM will be the first global model for seismic risk assessment at a national and regional scale, and aims to achieve broad scientific participation and independence. Its development will occur in a

  6. GEMS

    Science.gov (United States)

    Swank, Jean

    2009-01-01

    The prime scientific objectives of the Gravity and Extreme Magnetism SMEX, GEMS, are to determine the effects of the spin of black holes, the configurations of the magnetic fields of magnetars, and the structure of the supernova shocks which accelerate cosmic rays. In the cases of both stellar black holes and supermassive black holes, sensitivity to 1% polarization is needed to make diagnostic measurements of the net polarizations predicted for probable disk and corona models. GEMS can reach this goal for several Seyferts and quasars and measure the polarizations of representatives of a variety of other classes of X-ray sources, such as rotation-powered and accretion-powered pulsars. GEMS uses foil mirrors to maximize the collecting area achievable within the SMEX constraints. The polarimeters at the mirror foci are Time Projection Chambers which use the photoelectic effect to measure the polarization of the incident photon. We have built laboratory models with good efficiency and modulation in the 2-10 keV range. An attached small student experiment would add 0.5 keV sensitivity for bright soft sources. The instrument has a point spread function which allows measurement of structures in the brighter nearby supernova remnants. GEMS' Orbital Sciences spacecraft will rotate at a rate of 0.1 revolutions per minute during observations, so that systematic errors due to the detector can be detected and corrected. A program of 35 sources can be observed in 9 months. GEMS is designed for a two year lifetime which will allow a General Observer program that would more than double the number of sources measured. For subsets of black holes, neutron stars and supernova remnants, GEMS will measure the polarization of several sources, solving important questions while establishing the sensitivity required for future missions.

  7. GEM1: First-year modeling and IT activities for the Global Earthquake Model

    Science.gov (United States)

    Anderson, G.; Giardini, D.; Wiemer, S.

    2009-04-01

    GEM is a public-private partnership initiated by the Organisation for Economic Cooperation and Development (OECD) to build an independent standard for modeling and communicating earthquake risk worldwide. GEM is aimed at providing authoritative, open information about seismic risk and decision tools to support mitigation. GEM will also raise risk awareness and help post-disaster economic development, with the ultimate goal of reducing the toll of future earthquakes. GEM will provide a unified set of seismic hazard, risk, and loss modeling tools based on a common global IT infrastructure and consensus standards. These tools, systems, and standards will be developed in partnership with organizations around the world, with coordination by the GEM Secretariat and its Secretary General. GEM partners will develop a variety of global components, including a unified earthquake catalog, fault database, and ground motion prediction equations. To ensure broad representation and community acceptance, GEM will include local knowledge in all modeling activities, incorporate existing detailed models where possible, and independently test all resulting tools and models. When completed in five years, GEM will have a versatile, penly accessible modeling environment that can be updated as necessary, and will provide the global standard for seismic hazard, risk, and loss models to government ministers, scientists and engineers, financial institutions, and the public worldwide. GEM is now underway with key support provided by private sponsors (Munich Reinsurance Company, Zurich Financial Services, AIR Worldwide Corporation, and Willis Group Holdings); countries including Belgium, Germany, Italy, Singapore, Switzerland, and Turkey; and groups such as the European Commission. The GEM Secretariat has been selected by the OECD and will be hosted at the Eucentre at the University of Pavia in Italy; the Secretariat is now formalizing the creation of the GEM Foundation. Some of GEM's global

  8. GEM-AQ/EC, an on-line global multi-scale chemical weather modelling system: model development and evaluation of global aerosol climatology

    Directory of Open Access Journals (Sweden)

    S. L. Gong

    2012-09-01

    Full Text Available A global air quality modeling system GEM-AQ/EC was developed by implementing tropospheric chemistry and aerosol processes on-line into the Global Environmental Multiscale weather prediction modelGEM. Due to the multi-scale features of the GEM, the integrated model, GEM-AQ/EC, is able to investigate chemical weather at scales from global to urban domains. The current chemical mechanism is comprised of 50 gas-phase species, 116 chemical and 19 photolysis reactions, and is complemented by a sectional aerosol module CAM (The Canadian Aerosol Module with 5 aerosols types: sulphate, black carbon, organic carbon, sea-salt and soil dust. Monthly emission inventories of black carbon and organic carbon from boreal and temperate vegetation fires were assembled using the most reliable areas burned datasets by countries, from statistical databases and derived from remote sensing products of 1995–2004. The model was run for ten years from from 1995–2004 with re-analyzed meteorology on a global uniform 1° × 1° horizontal resolution domain and 28 hybrid levels extending up to 10 hPa. The simulating results were compared with various observations including surface network around the globe and satellite data. Regional features of global aerosols are reasonably captured including emission, surface concentrations and aerosol optical depth. For various types of aerosols, satisfactory correlations were achieved between modeled and observed with some degree of systematic bias possibly due to large uncertainties in the emissions used in this study. A global distribution of natural aerosol contributions to the total aerosols is obtained and compared with observations.

  9. Development and evaluation of an Earth-System model – HadGEM2

    Directory of Open Access Journals (Sweden)

    W. J. Collins

    2011-11-01

    Full Text Available We describe here the development and evaluation of an Earth system model suitable for centennial-scale climate prediction. The principal new components added to the physical climate model are the terrestrial and ocean ecosystems and gas-phase tropospheric chemistry, along with their coupled interactions.

    The individual Earth system components are described briefly and the relevant interactions between the components are explained. Because the multiple interactions could lead to unstable feedbacks, we go through a careful process of model spin up to ensure that all components are stable and the interactions balanced. This spun-up configuration is evaluated against observed data for the Earth system components and is generally found to perform very satisfactorily. The reason for the evaluation phase is that the model is to be used for the core climate simulations carried out by the Met Office Hadley Centre for the Coupled Model Intercomparison Project (CMIP5, so it is essential that addition of the extra complexity does not detract substantially from its climate performance. Localised changes in some specific meteorological variables can be identified, but the impacts on the overall simulation of present day climate are slight.

    This model is proving valuable both for climate predictions, and for investigating the strengths of biogeochemical feedbacks.

  10. Embedded controller for GEM detector readout system

    Science.gov (United States)

    Zabołotny, Wojciech M.; Byszuk, Adrian; Chernyshova, Maryna; Cieszewski, Radosław; Czarski, Tomasz; Dominik, Wojciech; Jakubowska, Katarzyna L.; Kasprowicz, Grzegorz; Poźniak, Krzysztof; Rzadkiewicz, Jacek; Scholz, Marek

    2013-10-01

    This paper describes the embedded controller used for the multichannel readout system for the GEM detector. The controller is based on the embedded Mini ITX mainboard, running the GNU/Linux operating system. The controller offers two interfaces to communicate with the FPGA based readout system. FPGA configuration and diagnostics is controlled via low speed USB based interface, while high-speed setup of the readout parameters and reception of the measured data is handled by the PCI Express (PCIe) interface. Hardware access is synchronized by the dedicated server written in C. Multiple clients may connect to this server via TCP/IP network, and different priority is assigned to individual clients. Specialized protocols have been implemented both for low level access on register level and for high level access with transfer of structured data with "msgpack" protocol. High level functionalities have been split between multiple TCP/IP servers for parallel operation. Status of the system may be checked, and basic maintenance may be performed via web interface, while the expert access is possible via SSH server. System was designed with reliability and flexibility in mind.

  11. Acid Deposition Simulations for Alberta, Saskatchewan, and the Canadian Oil Sands, using the Global Environmental Multiscale - Modelling Air-quality and CHemistry (GEM-MACH) System

    Science.gov (United States)

    Makar, Paul; Akingunola, Ayodeji; Moran, Michael; Wong, Isaac; Aherne, Julian; Hayden, Katherine; Li, Shao-Meng; Zhang, Junhua; Baratzedah, Pegha; Pabla, Balbir; Cheung, Philip; Cole, Amanda; Kirk, Jane; Scott, Ken

    2017-04-01

    The Global Environmental Multiscale - Modelling Air-quality and CHemistry (GEM-MACH) system (version 2) was used to carry out simulations of acid deposition for the Canadian provinces of Alberta and Saskatchewan. These model predictions include the hourly deposition of four sulphur and eleven nitrogen containing species (SO2(g), HSO3(-)(aq) , SO4(2-)(aq), particulate sulphate, and NH3(g), NO2(g), HNO3(g), NH4(+)(aq), NO3(-)(aq), HONO(g), PAN(g), HNO4(g), particulate nitrate, particulate ammonium, and gaseous organic nitrate, respectively). A two-bin aerosol size distribution configuration of GEM-MACH was used to estimate the annual deposition of these chemicals, for the period August 1, 2013 through July 31, 2014, at two resolutions—a 10km resolution North American domain and a 2.5km resolution Alberta and Saskatchewan domain. The model estimates of acid deposition from both resolutions (version 2), were used to determine the relative contributions of the different species towards total sulphur and nitrogen deposition, and to evaluate the effect of model resolution on estimates of acid deposition. The potential ecosystem impacts of acid deposition were examined via comparison of model-predicted total deposition to different sources of sulphur and nitrogen critical load data, for forest and lake ecosystems in northern Alberta and Saskatchewan. The deposition estimates were compared to observations of snowpack sulphur and nitrogen ions, collected during the winter of 2013. The processes underlying acidifying deposition in the vicinity of the Canadian oil sands were examined in more detail using the 12-bin aerosol size distribution configuration of GEM-MACH (version 2), for a period from mid-August to mid-September 2013. This time period corresponds to an aircraft measurement intensive campaign designed to examine emissions, transportation, and deposition associated with air pollution sources in the Canadian oil sands. Multiple model simulation scenarios were

  12. GEM-AQ, an on-line global multiscale chemical weather modelling system: model description and evaluation of gas phase chemistry processes

    Directory of Open Access Journals (Sweden)

    J. W. Kaminski

    2008-06-01

    Full Text Available Tropospheric chemistry and air quality processes were implemented on-line in the Global Environmental Multiscale weather prediction model. The integrated model, GEM-AQ, was developed as a platform to investigate chemical weather at scales from global to urban. The current chemical mechanism is comprised of 50 gas-phase species, 116 chemical and 19 photolysis reactions, and is complemented by a sectional aerosol module with 5 aerosols types. All tracers are advected using the semi-Lagrangian scheme native to GEM. The vertical transport includes parameterized subgrid-scale turbulence and large scale deep convection. Dry deposition is included as a flux boundary condition in the vertical diffusion equation. Wet deposition of gas-phase species is treated in a simplified way, and only below-cloud scavenging is considered. The emissions used include yearly-averaged anthropogenic, and monthly-averaged biogenic, ocean, soil, and biomass burning emission fluxes, as well as NOx from lightning. In order to evaluate the ability to simulate seasonal variations and regional distributions of trace gases such as ozone, nitrogen dioxide and carbon monoxide, the model was run for a period of five years (2001–2005 on a global uniform 1.5°×1.5° horizontal resolution domain and 28 hybrid levels extending up to 10 hPa. Model results were compared with observations from satellites, aircraft measurement campaigns and balloon sondes. We find that GEM-AQ is able to capture the spatial details of the chemical fields in the middle and lower troposphere. The modelled ozone consistently shows good agreement with observations, except over tropical oceans. The comparison of carbon monoxide and nitrogen dioxide with satellite measurements emphasizes the need for more accurate, year-specific emissions fluxes for biomass burning and anthropogenic sources. Other species also compare well with available observations.

  13. Assessing the performance of gas collection systems in select Chinese landfills according to the LandGEM model: drawbacks and potential direction.

    Science.gov (United States)

    Sun, Yue; Yue, Dongbei; Li, Rundong; Yang, Ting; Liu, Shiliang

    2015-01-01

    In China, municipal solid waste (MSW) is primarily treated by landfilling. Landfill gas (LFG) collection effectively reduces methane emission from MSW landfills. An accurate system of LFG collection is important in landfill planning, design, and operation. However, China has not developed such systems. In this study, the efficiency of methane collection is calculated in three Chinese landfills with different collection systems (A: vertical wells for MSW before 2010; combined horizontal trenches and under-membrane pipes for MSW from 2011 onwards; B: combined horizontal trenches and vertical wells; C: vertical wells only). This efficiency was computed by dividing the quantity of methane obtained from landfill operation records by the quantity estimated based on the LandGEM model. Results show that the collection efficiencies of landfills with vertical wells and/or horizontal pipes ranged from 8.3% to 27.9%, whereas those of a system equipped with geomembrane reached 65.3%. The poor performance of the landfills was attributed to the open burning of early-stage LFG, LFG release from cracks in high-density polyethylene covers, and high levels of leachate within a landfill site. Therefore, this study proposes an integrated LFG collection system that can remove leachate and collect gas from landfills that accept waste with high moisture content.

  14. Improved model of the Earth's gravitational field: GEM-T1

    International Nuclear Information System (INIS)

    Marsh, J.G.; Lerch, F.J.; Christodoulidis, D.C.

    1987-07-01

    Goddard Earth Model T1 (GEM-T1), which was developed from an analysis of direct satellite tracking observations, is the first in a new series of such models. GEM-T1 is complete to degree and order 36. It was developed using consistent reference parameters and extensive earth and ocean tidal models. It was simultaneously solved for gravitational and tidal terms, earth orientation parameters, and the orbital parameters of 580 individual satellite arcs. The solution used only satellite tracking data acquired on 17 different satellites and is predominantly based upon the precise laser data taken by third generation systems. In all, 800,000 observations were used. A major improvement in field accuracy was obtained. For marine geodetic applications, long wavelength geoidal modeling is twice as good as in earlier satellite-only GEM models. Orbit determination accuracy has also been substantially advanced over a wide range of satellites that have been tested

  15. The HadGEM2 family of Met Office Unified Model climate configurations

    Directory of Open Access Journals (Sweden)

    The HadGEM2 Development Team: G. M. Martin

    2011-09-01

    Full Text Available We describe the HadGEM2 family of climate configurations of the Met Office Unified Model, MetUM. The concept of a model "family" comprises a range of specific model configurations incorporating different levels of complexity but with a common physical framework. The HadGEM2 family of configurations includes atmosphere and ocean components, with and without a vertical extension to include a well-resolved stratosphere, and an Earth-System (ES component which includes dynamic vegetation, ocean biology and atmospheric chemistry. The HadGEM2 physical model includes improvements designed to address specific systematic errors encountered in the previous climate configuration, HadGEM1, namely Northern Hemisphere continental temperature biases and tropical sea surface temperature biases and poor variability. Targeting these biases was crucial in order that the ES configuration could represent important biogeochemical climate feedbacks. Detailed descriptions and evaluations of particular HadGEM2 family members are included in a number of other publications, and the discussion here is limited to a summary of the overall performance using a set of model metrics which compare the way in which the various configurations simulate present-day climate and its variability.

  16. Climate and land use change impacts on global terrestrial ecosystems and river flows in the HadGEM2-ES Earth system model using the representative concentration pathways

    Science.gov (United States)

    Betts, R. A.; Golding, N.; Gonzalez, P.; Gornall, J.; Kahana, R.; Kay, G.; Mitchell, L.; Wiltshire, A.

    2015-03-01

    A new generation of an Earth system model now includes a number of land-surface processes directly relevant to analyzing potential impacts of climate change. This model, HadGEM2-ES, allows us to assess the impacts of climate change, multiple interactions, and feedbacks as the model is run. This paper discusses the results of century-scale HadGEM2-ES simulations from an impacts perspective - specifically, terrestrial ecosystems and water resources - for four different scenarios following the representative concentration pathways (RCPs), used in the Fifth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC, 2013, 2014). Over the 21st century, simulated changes in global and continental-scale terrestrial ecosystems due to climate change appear to be very similar in all 4 RCPs, even though the level of global warming by the end of the 21st century ranges from 2 °C in the lowest scenario to 5.5° in the highest. A warming climate generally favours broadleaf trees over needleleaf, needleleaf trees over shrubs, and shrubs over herbaceous vegetation, resulting in a poleward shift of temperate and boreal forests and woody tundra in all scenarios. Although climate related changes are slightly larger in scenarios of greater warming, the largest differences between scenarios arise at regional scales as a consequence of different patterns of anthropogenic land cover change. In the model, the scenario with the lowest global warming results in the most extensive decline in tropical forest cover due to a large expansion of agriculture. Under all four RCPs, fire potential could increase across extensive land areas, particularly tropical and sub-tropical latitudes. River outflows are simulated to increase with higher levels of CO2 and global warming in all projections, with outflow increasing with mean temperature at the end of the 21st century at the global scale and in North America, Asia, and Africa. In South America, Europe, and Australia, the relationship

  17. Inpatient geriatric evaluation and management units (GEMs) in the veterans health system: diamonds in the rough?

    Science.gov (United States)

    Wieland, D; Rubenstein, L Z; Hedrick, S C; Reuben, D B; Buchner, D M

    1994-09-01

    Research suggests that inpatient geriatric evaluation and management units (GEMs), which undertake interdisciplinary diagnosis to improve the health of frail elderly patients, are effective. The Department of Veterans Affairs (VA) helped pioneer U.S. GEMs and mandates that every facility shall have a GEM by 1996. We conducted a population survey of VA GEMs in 1991 to assess their dissemination. Various organizational and performance characteristics of GEMs were entered in a data base derived from a piloted questionnaire and administrative records. Basic criteria from consensus reports were used to classify and compare "standard" and "nonstandard" GEMs. The criteria covered performance of assessment, team structure, patient selection, GEM location, and treatment functions. We analyzed the effect of GEM type and other factors on length of stay and placement. Reasons for closure of GEMs inactive in 1991 were recovered, and GEMs active in 1991 but later closed are described. As of 1991, 41 of 73 GEMs were classified as standard, and 32 nonstandard. Standard compared to nonstandard GEMs had shorter stays (25.4 vs 69.9 days; p home discharge rates (63.4% vs 40%; p nursing home placement rates (19.1% vs 40.3%; p closure. Additional work is needed to monitor GEM proliferation, implementation, and performance in and out of the VA system.

  18. Modelling Chemical Equilibrium Partitioning with the GEMS-PSI Code

    Energy Technology Data Exchange (ETDEWEB)

    Kulik, D.; Berner, U.; Curti, E

    2004-03-01

    Sorption, co-precipitation and re-crystallisation are important retention processes for dissolved contaminants (radionuclides) migrating through the sub-surface. The retention of elements is usually measured by empirical partition coefficients (Kd), which vary in response to many factors: temperature, solid/liquid ratio, total contaminant loading, water composition, host-mineral composition, etc. The Kd values can be predicted for in-situ conditions from thermodynamic modelling of solid solution, aqueous solution or sorption equilibria, provided that stoichiometry, thermodynamic stability and mixing properties of the pure components are known (Example 1). Unknown thermodynamic properties can be retrieved from experimental Kd values using inverse modelling techniques (Example 2). An efficient, advanced tool for performing both tasks is the Gibbs Energy Minimization (GEM) approach, implemented in the user-friendly GEM-Selector (GEMS) program package, which includes the Nagra-PSI chemical thermodynamic database. The package is being further developed at PSI and used extensively in studies relating to nuclear waste disposal. (author)

  19. Modelling Chemical Equilibrium Partitioning with the GEMS-PSI Code

    International Nuclear Information System (INIS)

    Kulik, D.; Berner, U.; Curti, E.

    2004-01-01

    Sorption, co-precipitation and re-crystallisation are important retention processes for dissolved contaminants (radionuclides) migrating through the sub-surface. The retention of elements is usually measured by empirical partition coefficients (Kd), which vary in response to many factors: temperature, solid/liquid ratio, total contaminant loading, water composition, host-mineral composition, etc. The Kd values can be predicted for in-situ conditions from thermodynamic modelling of solid solution, aqueous solution or sorption equilibria, provided that stoichiometry, thermodynamic stability and mixing properties of the pure components are known (Example 1). Unknown thermodynamic properties can be retrieved from experimental Kd values using inverse modelling techniques (Example 2). An efficient, advanced tool for performing both tasks is the Gibbs Energy Minimization (GEM) approach, implemented in the user-friendly GEM-Selector (GEMS) program package, which includes the Nagra-PSI chemical thermodynamic database. The package is being further developed at PSI and used extensively in studies relating to nuclear waste disposal. (author)

  20. The GEM-Mars general circulation model for Mars: Description and evaluation

    Science.gov (United States)

    Neary, L.; Daerden, F.

    2018-01-01

    GEM-Mars is a gridpoint-based three-dimensional general circulation model (GCM) of the Mars atmosphere extending from the surface to approximately 150 km based on the GEM (Global Environmental Multiscale) model, part of the operational weather forecasting and data assimilation system for Canada. After the initial modification for Mars, the model has undergone considerable changes. GEM-Mars is now based on GEM 4.2.0 and many physical parameterizations have been added for Mars-specific atmospheric processes and surface-atmosphere exchange. The model simulates interactive carbon dioxide-, dust-, water- and atmospheric chemistry cycles. Dust and water ice clouds are radiatively active. Size distributed dust is lifted by saltation and dust devils. The model includes 16 chemical species (CO2, Argon, N2, O2, CO, H2O, CH4, O3, O(1D), O, H, H2, OH, HO2, H2O2 and O2(a1Δg)) and has fully interactive photochemistry (15 reactions) and gas-phase chemistry (31 reactions). GEM-Mars provides a good simulation of the water and ozone cycles. A variety of other passive tracers can be included for dedicated studies, such as the emission of methane. The model has both a hydrostatic and non-hydrostatic formulation, and together with a flexible grid definition provides a single platform for simulations on a variety of horizontal scales. The model code is fully parallelized using OMP and MPI. Model results are evaluated by comparison to a selection of observations from instruments on the surface and in orbit, relating to atmosphere and surface temperature and pressure, dust and ice content, polar ice mass, polar argon, and global water and ozone vertical columns. GEM-Mars will play an integral part in the analysis and interpretation of data that is received by the NOMAD spectrometer on the ESA-Roskosmos ExoMars Trace Gas Orbiter. The present paper provides an overview of the current status and capabilities of the GEM-Mars model and lays the foundations for more in-depth studies in support

  1. Computational modeling of induced emotion using GEMS

    NARCIS (Netherlands)

    Aljanaki, Anna; Wiering, Frans; Veltkamp, Remco

    2014-01-01

    Most researchers in the automatic music emotion recognition field focus on the two-dimensional valence and arousal model. This model though does not account for the whole diversity of emotions expressible through music. Moreover, in many cases it might be important to model induced (felt) emotion,

  2. Modelling of the soft X-ray tungsten spectra expected to be registered by GEM detection system for WEST

    Directory of Open Access Journals (Sweden)

    Syrocki Łukasz

    2016-12-01

    Full Text Available In the future International Thermonuclear Experimental Reactor (ITER, the interaction between the plasma and the tungsten chosen as the plasma-facing wall material imposes that the hot central plasma loses energy by X-ray emission from tungsten ions. On the other hand, the registered X-ray spectra provide alternative diagnostics of the plasma itself. Highly ionized tungsten emits extremely complex X-ray spectra that can be understood only after exhaustive theoretical studies. The detailed analyses will be useful for proper interpretation of soft X-ray plasma radiation expected to be registered on ITER-like machines, that is, Tungsten (W Environment in Steady-state Tokamak (WEST. The simulations of the soft X-ray spectra structures for tungsten ions have been performed using the flexible atomic code (FAC package within the framework of collisional-radiative (CR model approach for electron temperatures and densities relevant to WEST tokamak.

  3. GEM-SELEKTOR Geochemical Modeling Package: TSolMod library and data interface for multicomponent phase models

    OpenAIRE

    Wagner T.; Kulik D. A.; Hingerl F. F.; Dmytrieva S. V.

    2012-01-01

    The development of highly accurate and computationally efficient modeling software based on Gibbs energy minimization (GEM) makes it possible to thermodynamically simulate geochemically realistic subsurface fluid rock interaction processes. This involves consideration of non ideal multicomponent multiphase systems that include dilute to concentrated aqueous electrolyte solutions mineral solid solutions supercritical fluids silicate and metal melts and sorption and ion exchange phases. Predict...

  4. Overview of the Gems Model of Volunteer Administration (Generate, Educate, Mobilize and Sustain)

    Science.gov (United States)

    Culp, Ken, III

    2012-01-01

    To organize and coordinate the efforts of many volunteers, a framework for volunteer engagement is needed. The "GEMS" Model of volunteer administration was developed to assist Extension professionals and volunteer coordinators to effectively administer volunteer programs without delivering the program themselves. The GEMS Model is…

  5. Gillespie eco-evolutionary models (GEMs) reveal the role of heritable trait variation in eco-evolutionary dynamics.

    Science.gov (United States)

    DeLong, John P; Gibert, Jean P

    2016-02-01

    Heritable trait variation is a central and necessary ingredient of evolution. Trait variation also directly affects ecological processes, generating a clear link between evolutionary and ecological dynamics. Despite the changes in variation that occur through selection, drift, mutation, and recombination, current eco-evolutionary models usually fail to track how variation changes through time. Moreover, eco-evolutionary models assume fitness functions for each trait and each ecological context, which often do not have empirical validation. We introduce a new type of model, Gillespie eco-evolutionary models (GEMs), that resolves these concerns by tracking distributions of traits through time as eco-evolutionary dynamics progress. This is done by allowing change to be driven by the direct fitness consequences of model parameters within the context of the underlying ecological model, without having to assume a particular fitness function. GEMs work by adding a trait distribution component to the standard Gillespie algorithm - an approach that models stochastic systems in nature that are typically approximated through ordinary differential equations. We illustrate GEMs with the Rosenzweig-MacArthur consumer-resource model. We show not only how heritable trait variation fuels trait evolution and influences eco-evolutionary dynamics, but also how the erosion of variation through time may hinder eco-evolutionary dynamics in the long run. GEMs can be developed for any parameter in any ordinary differential equation model and, furthermore, can enable modeling of multiple interacting traits at the same time. We expect GEMs will open the door to a new direction in eco-evolutionary and evolutionary modeling by removing long-standing modeling barriers, simplifying the link between traits, fitness, and dynamics, and expanding eco-evolutionary treatment of a greater diversity of ecological interactions. These factors make GEMs much more than a modeling advance, but an important

  6. GEM-E3: A computable general equilibrium model applied for Switzerland

    Energy Technology Data Exchange (ETDEWEB)

    Bahn, O. [Paul Scherrer Inst., CH-5232 Villigen PSI (Switzerland); Frei, C. [Ecole Polytechnique Federale de Lausanne (EPFL) and Paul Scherrer Inst. (Switzerland)

    2000-01-01

    The objectives of the European Research Project GEM-E3-ELITE, funded by the European Commission and coordinated by the Centre for European Economic Research (Germany), were to further develop the general equilibrium model GEM-E3 (Capros et al., 1995, 1997) and to conduct policy analysis through case studies. GEM-E3 is an applied general equilibrium model that analyses the macro-economy and its interaction with the energy system and the environment through the balancing of energy supply and demand, atmospheric emissions and pollution control, together with the fulfillment of overall equilibrium conditions. PSI's research objectives within GEM-E3-ELITE were to implement and apply GEM-E3 for Switzerland. The first objective required in particular the development of a Swiss database for each of GEM-E3 modules (economic module and environmental module). For the second objective, strategies to reduce CO{sub 2} emissions were evaluated for Switzerland. In order to develop the economic, PSI collaborated with the Laboratory of Applied Economics (LEA) of the University of Geneva and the Laboratory of Energy Systems (LASEN) of the Federal Institute of Technology in Lausanne (EPFL). The Swiss Federal Statistical Office (SFSO) and the Institute for Business Cycle Research (KOF) of the Swiss Federal Institute of Technology (ETH Zurich) contributed also data. The Swiss environmental database consists mainly of an Energy Balance Table and of an Emission Coefficients Table. Both were designed using national and international official statistics. The Emission Coefficients Table is furthermore based on know-how of the PSI GaBE Project. Using GEM-E3 Switzerland, two strategies to reduce the Swiss CO{sub 2} emissions were evaluated: a carbon tax ('tax only' strategy), and the combination of a carbon tax with the buying of CO{sub 2} emission permits ('permits and tax' strategy). In the first strategy, Switzerland would impose the necessary carbon tax to achieve

  7. GEM-E3: A computable general equilibrium model applied for Switzerland

    International Nuclear Information System (INIS)

    Bahn, O.; Frei, C.

    2000-01-01

    The objectives of the European Research Project GEM-E3-ELITE, funded by the European Commission and coordinated by the Centre for European Economic Research (Germany), were to further develop the general equilibrium model GEM-E3 (Capros et al., 1995, 1997) and to conduct policy analysis through case studies. GEM-E3 is an applied general equilibrium model that analyses the macro-economy and its interaction with the energy system and the environment through the balancing of energy supply and demand, atmospheric emissions and pollution control, together with the fulfillment of overall equilibrium conditions. PSI's research objectives within GEM-E3-ELITE were to implement and apply GEM-E3 for Switzerland. The first objective required in particular the development of a Swiss database for each of GEM-E3 modules (economic module and environmental module). For the second objective, strategies to reduce CO 2 emissions were evaluated for Switzerland. In order to develop the economic, PSI collaborated with the Laboratory of Applied Economics (LEA) of the University of Geneva and the Laboratory of Energy Systems (LASEN) of the Federal Institute of Technology in Lausanne (EPFL). The Swiss Federal Statistical Office (SFSO) and the Institute for Business Cycle Research (KOF) of the Swiss Federal Institute of Technology (ETH Zurich) contributed also data. The Swiss environmental database consists mainly of an Energy Balance Table and of an Emission Coefficients Table. Both were designed using national and international official statistics. The Emission Coefficients Table is furthermore based on know-how of the PSI GaBE Project. Using GEM-E3 Switzerland, two strategies to reduce the Swiss CO 2 emissions were evaluated: a carbon tax ('tax only' strategy), and the combination of a carbon tax with the buying of CO 2 emission permits ('permits and tax' strategy). In the first strategy, Switzerland would impose the necessary carbon tax to achieve the reduction target, and use the tax

  8. An Interactive Java Statistical Image Segmentation System: GemIdent.

    Science.gov (United States)

    Holmes, Susan; Kapelner, Adam; Lee, Peter P

    2009-06-01

    Supervised learning can be used to segment/identify regions of interest in images using both color and morphological information. A novel object identification algorithm was developed in Java to locate immune and cancer cells in images of immunohistochemically-stained lymph node tissue from a recent study published by Kohrt et al. (2005). The algorithms are also showing promise in other domains. The success of the method depends heavily on the use of color, the relative homogeneity of object appearance and on interactivity. As is often the case in segmentation, an algorithm specifically tailored to the application works better than using broader methods that work passably well on any problem. Our main innovation is the interactive feature extraction from color images. We also enable the user to improve the classification with an interactive visualization system. This is then coupled with the statistical learning algorithms and intensive feedback from the user over many classification-correction iterations, resulting in a highly accurate and user-friendly solution. The system ultimately provides the locations of every cell recognized in the entire tissue in a text file tailored to be easily imported into R (Ihaka and Gentleman 1996; R Development Core Team 2009) for further statistical analyses. This data is invaluable in the study of spatial and multidimensional relationships between cell populations and tumor structure. This system is available at http://www.GemIdent.com/ together with three demonstration videos and a manual.

  9. Design and creating model and interactive presentation of GEM for Microcosm Exhibition

    CERN Document Server

    Lakdee, Natthaphop

    2017-01-01

    GEM or Gas Electron Multiplier is the newer and easier way to amplify electron signal than conventional CSS. It was first created by Fabio Sauli at CERN in 1997 and was developed to get better efficiency over time. Right now, it was brought to use in many detector stations at CERN. To make GEM more publicly known, one of the ways is show in Microcosm Exhibition which is always visited by people from around the world everyday, so my main project as summer student is to design and create the model and interactive presentation which make GEM interesting and easy to understand by ordinary people.

  10. The BlackGEM array in search of black hole mergers: integrated performance modelling

    Science.gov (United States)

    Roelfsema, Ronald; Klein Wolt, Marc; Bloemen, Steven; Groot, Paul; Bettonvil, Felix; Balster, Harry; Dolron, Peter; van Elteren, Arjen; Engels, Arno; de Haan, Menno; ter Horst, Rik; Kragt, Jan; Navarro, Ramon; Nelemans, Gijs; Paalberends, Willem Jelle; Pal, Sari; Raskin, Gert; Rutten, Harrie; Scheers, Bart; Schuil, Menno; Sybilski, Piotr

    2016-07-01

    The Radboud University Nijmegen in collaboration with the NOVA Optical Infrared Instrumentation group at ASTRON is currently leading the development and realization of the BlackGEM observing facility. The BlackGEM science team aims to be the first to catch the optical counterpart of a gravitational wave event. The BlackGEM project will put an array of three medium-sized optical telescopes at the La Silla site of the European Southern Observatory in Chile. It is uniquely equipped to achieve a combination of wide-field and high sensitivity through its array-like approach. Each BlackGEM unit telescope is a modified Dall-Kirkham-type telescope consisting of a 65cm primary mirror, a 21cm spherical secondary mirror and a triplet corrector lens. The spatial resolution on the sky will be 0.56 asec/pixel and the total field-of-view per telescope is 2.7 square degrees. The main requirement is to achieve a 5-sigma sensitivity of 23rd magnitude within a 5-minute exposure under 15 m/s wind gust conditions. This demands a very stable optical system with tight control of all the error contributions. This has been realized with a spreadsheet based integrated instrument model. The model contains all relevant telescope instrument parameters and environmental conditions. The spreadsheet is partly used for performance calculations and partly used to combine and integrate the output from several other sources. The spreadsheet model calculates the overall performance based on an Exposure Time Calculator using the Noise Equivalent Area metric (NEA). The NEA is further budgeted over 7 main High Level Requirements. The spreadsheet model is coupled to 1) a ZEMAX telescope optical model 2) a telescope FEM analysis to predict the optomechanical response under various gravity, temperature and wind load conditions, 3) a Matlab Simulink thermal model to predict the transient temperature behaviour of the most important telescope elements and 4) a Matlab Simulink control model to predict the

  11. The Triple GEM Detector Control System for CMS forward muon spectrometer upgrade

    Science.gov (United States)

    Ahmed, W.; Abbaneo, D.; Abbrescia, M.; Abdelalim, A. A.; Abi. Akl, M.; Acosta, D.; Ahmad, A.; Ahmed, W.; Aleksandrov, A.; Aly, R.; Altieri, P.; Asawatangtrakuldee, C.; Aspell, P.; Assran, Y.; Awan, I.; Bally, S.; Ban, Y.; Banerjee, S.; Barashko, V.; Barria, P.; Bencze, G.; Beni, N.; Benussi, L.; Bhopatkar, V.; Bianco, S.; Bos, J.; Bouhali, O.; Holme, O.; Braghieri, A.; Braibant, S.; Buontempo, S.; Khan, S. A.; Calabria, C.; Caponero, M.; Caputo, C.; Cassese, F.; Castaneda, A.; Cauwenbergh, S.; Cavallo, F. R.; Celik, A.; Choi, M.; Choi, S.; Christiansen, J.; Cimmino, A.; Colafranceschi, S.; Colaleo, A.; Conde Garcia, A.; Czellar, S.; Dabrowski, M. M.; Lentdecker, G. De.; De Oliveira, R.; de Robertis, G.; Dildick, S.; Dorney, B.; Elmetenawee, W.; Endroczi, G.; Errico, F.; Fenyvesi, A.; Ferry, S.; Furic, I.; Giacomelli, P.; Gilmore, J.; Golovtsov, V.; Guiducci, L.; Guilloux, F.; Gutierrez, A.; Hadjiiska, R. M.; Hassan, A.; Hauser, J.; Hoepfner, K.; Hohlmann, M.; Hoorani, H.; Shah, A. H.; Iaydjiev, P.; Jeng, Y. G.; Kamon, T.; Karchin, P.; Korytov, A.; Krutelyov, S.; Kumar, A.; Kim, H.; Lenzi, T.; Litov, L.; Loddo, F.; Madorsky, A.; Maerschalk, T.; Maggi, M.; Magnani, A.; Mal, P. K.; Mandal, K.; Marchioro, A.; Marinov, A.; Majumdar, N.; Merlin, J. A.; Mitselmakher, G.; Mohanty, A. K.; Mohapatra, A.; Molnar, J.; Muhammad, S.; Mukhopadhyay, S.; Naimuddin, M.; Nuzzo, S.; Oliveri, E.; Pant, L. M.; Paolucci, P.; Park, I.; Passeggio, G.; Pavlov, B.; Philipps, B.; Piccolo, D.; Postema, H.; Puig. Baranac, A.; Radi, A.; Radogna, R.; Raffone, G.; Ranieri, A.; Rashevski, G.; Riccardi, C.; Rodozov, M.; Rodrigues, A.; Ropelewski, L.; RoyChowdhury, S.; Ryu, G.; Ryu, M. S.; Safonov, A.; Salva, S.; Saviano, G.; Sharma, A.; Sharma, R.; Shopova, M.; Sturdy, J.; Sultanov, G.; Swain, S. K.; Szillasi, Z.; Talvitie, J.; Tatarinov, A.; Tuuva, T.; Tytgat, M.; Vai, I.; Van Stenis, M.; Venditti, R.; Verhagen, E.; Verwilligen, P.; Vitulo, P.; Volkov, S.; Vorobyev, A.; Wang, D.; Wang, M.; Yang, U.; Yang, Y.; Yonamine, R.; Zaganidis, N.; Zenoni, F.; Zhang, A.

    2017-02-01

    The CMS experiment at LHC will upgrade its forward muon spectrometer by incorporating Triple-GEM detectors. This upgrade referred to as GEM Endcap (GE1/1), consists of adding two back-to-back Triple-GEM detectors in front of the existing Cathode Strip Chambers (CSC) in the innermost ring of the endcap muon spectrometer. Before the full installation of 144 detectors in 2019-2020, CMS will first install ten single chamber prototypes during the early 2017. This pre-installation is referred as the slice test. These ten detectors will be read-out by VFAT2 chips [1]. On-detector there is also a FPGA mezzanine card which sends VFAT2 data optically to the μTCA back-end electronics. The correct and safe operation of the GEM system requires a sophisticated and powerful online Detector Control System, able to monitor and control many heterogeneous hardware devices. The DCS system developed for the slice test has been tested with CMS Triple-GEM detectors in the laboratory. In this paper we describe the newly developed DCS system and present the first results obtained in the GEM assembly and quality assurance laboratory.

  12. Climate and land use change impacts on global terrestrial ecosystems, fire, and river flows in the HadGEM2-ES Earth System Model using the Representative Concentration Pathways

    Science.gov (United States)

    Betts, R. A.; Golding, N.; Gonzalez, P.; Gornall, J.; Kahana, R.; Kay, G.; Mitchell, L.; Wiltshire, A.

    2013-04-01

    A new generation of an Earth System Model now includes a number of land surface processes directly relevant to analyzing potential impacts of climate change. This model, HadGEM2-ES, allows us to assess the impacts of climate change, multiple interactions, and feedbacks as the model is run. This paper discusses the results of century-scale HadGEM2-ES simulations from an impacts perspective-specifically, terrestrial ecosystems and water resources-for four different scenarios following the Representative Concentration Pathways (RCPs), being used for next assessment report of the Intergovernmental Panel on Climate Change (IPCC). Over the 21st Century, simulated changes in global and continential-scale terrestrial ecosystems due to climate change appear to be very similar in all 4 RCPs, even though the level of global warming by the end of the 21st Century ranges from 2 °C in the lowest scenario to 5.5° in the highest. A warming climate generally favours broadleaf trees over needleleaf, needleleaf trees over shrubs, and shrubs over herbaceous vegetation, resulting in a poleward shift of temperate and boreal forests and woody tundra in all scenarios. Although climate related changes are slightly larger in scenarios of greater warming, the largest differences between scenarios arise at regional scales as a consequence of different patterns of anthropogenic land cover change. In the model, the scenario with the lowest global warming results in the most extensive decline in tropical forest cover due to a large expansion of agriculture. Under all four RCPs, fire potential could increase across extensive land areas, particularly tropical and sub-tropical latitudes. River outflows are simulated to increase with higher levels of CO2 and global warming in all projections, with outflow increasing with mean temperature at the end of the 21st Century at the global scale and in North America, Asia, and Africa. In South America, Europe, and Australia, the relationship with climate

  13. A novel High-Voltage System for a triple GEM detector

    CERN Document Server

    Corradi, Giovanni; Tagnani, Diego; 10.1016/j.nima.2006.10.166

    2007-01-01

    A novel High-Voltage System for a triple GEM detector has been designed and realized in Frascati within the LHCb muon detector framework. The system is built with seven floating power supply, with a maximum of 1200 V each, and controlled via CANbus, for voltage settings and monitoring. Several HV modules can be installed in a nano-ammeter mainframe already developed in Frascati, realizing a HV crate able to supply up to 24 triple GEM chambers with a 1 nA resolution monitoring system.

  14. The game-based learning evaluation model (GEM): measuring the effectiveness of serious games using a standardised method

    NARCIS (Netherlands)

    Oprins, E.A.P.B.; Visschedijk, G.C.; Bakhuys Roozeboom, M.M.C.; Dankbaar, M.; Trooster, W.; Schuit, S.C.E.

    2015-01-01

    This article describes the background, design, and practical application of the game-based evaluation model (GEM). The aim of this evaluation model is to measure the effectiveness of serious games in a practical way. GEM contains the methodology and indicators to be measured in validation research.

  15. Sensitivity analysis of the GEMS soil organic carbon model to land cover land use classification uncertainties under different climate scenarios in Senegal

    Science.gov (United States)

    Dieye, A.M.; Roy, David P.; Hanan, N.P.; Liu, S.; Hansen, M.; Toure, A.

    2012-01-01

    Spatially explicit land cover land use (LCLU) change information is needed to drive biogeochemical models that simulate soil organic carbon (SOC) dynamics. Such information is increasingly being mapped using remotely sensed satellite data with classification schemes and uncertainties constrained by the sensing system, classification algorithms and land cover schemes. In this study, automated LCLU classification of multi-temporal Landsat satellite data were used to assess the sensitivity of SOC modeled by the Global Ensemble Biogeochemical Modeling System (GEMS). The GEMS was run for an area of 1560 km2 in Senegal under three climate change scenarios with LCLU maps generated using different Landsat classification approaches. This research provides a method to estimate the variability of SOC, specifically the SOC uncertainty due to satellite classification errors, which we show is dependent not only on the LCLU classification errors but also on where the LCLU classes occur relative to the other GEMS model inputs.

  16. FPGA-based GEM detector signal acquisition for SXR spectroscopy system

    Science.gov (United States)

    Wojenski, A.; Pozniak, K. T.; Kasprowicz, G.; Kolasinski, P.; Krawczyk, R.; Zabolotny, W.; Chernyshova, M.; Czarski, T.; Malinowski, K.

    2016-11-01

    The presented work is related to the Gas Electron Multiplier (GEM) detector soft X-ray spectroscopy system for tokamak applications. The used GEM detector has one-dimensional, 128 channel readout structure. The channels are connected to the radiation-hard electronics with configurable analog stage and fast ADCs, supporting speeds of 125 MSPS for each channel. The digitalized data is sent directly to the FPGAs using fast serial links. The preprocessing algorithms are implemented in the FPGAs, with the data buffering made in the on-board 2Gb DDR3 memory chips. After the algorithmic stage, the data is sent to the Intel Xeon-based PC for further postprocessing using PCI-Express link Gen 2. For connection of multiple FPGAs, PCI-Express switch 8-to-1 was designed. The whole system can support up to 2048 analog channels. The scope of the work is an FPGA-based implementation of the recorder of the raw signal from GEM detector. Since the system will work in a very challenging environment (neutron radiation, intense electro-magnetic fields), the registered signals from the GEM detector can be corrupted. In the case of the very intense hot plasma radiation (e.g. laser generated plasma), the registered signals can overlap. Therefore, it is valuable to register the raw signals from the GEM detector with high number of events during soft X-ray radiation. The signal analysis will have the direct impact on the implementation of photon energy computation algorithms. As the result, the system will produce energy spectra and topological distribution of soft X-ray radiation. The advanced software was developed in order to perform complex system startup and monitoring of hardware units. Using the array of two one-dimensional GEM detectors it will be possible to perform tomographic reconstruction of plasma impurities radiation in the SXR region.

  17. FPGA-based GEM detector signal acquisition for SXR spectroscopy system

    International Nuclear Information System (INIS)

    Wojenski, A.; Pozniak, K. T.; Kasprowicz, G.; Kolasinski, P.; Krawczyk, R.; Zabolotny, W.; Chernyshova, M.; Czarski, T.; Malinowski, K.

    2016-01-01

    The presented work is related to the Gas Electron Multiplier (GEM) detector soft X-ray spectroscopy system for tokamak applications. The used GEM detector has one-dimensional, 128 channel readout structure. The channels are connected to the radiation-hard electronics with configurable analog stage and fast ADCs, supporting speeds of 125 MSPS for each channel. The digitalized data is sent directly to the FPGAs using fast serial links. The preprocessing algorithms are implemented in the FPGAs, with the data buffering made in the on-board 2Gb DDR3 memory chips. After the algorithmic stage, the data is sent to the Intel Xeon-based PC for further postprocessing using PCI-Express link Gen 2. For connection of multiple FPGAs, PCI-Express switch 8-to-1 was designed. The whole system can support up to 2048 analog channels. The scope of the work is an FPGA-based implementation of the recorder of the raw signal from GEM detector. Since the system will work in a very challenging environment (neutron radiation, intense electro-magnetic fields), the registered signals from the GEM detector can be corrupted. In the case of the very intense hot plasma radiation (e.g. laser generated plasma), the registered signals can overlap. Therefore, it is valuable to register the raw signals from the GEM detector with high number of events during soft X-ray radiation. The signal analysis will have the direct impact on the implementation of photon energy computation algorithms. As the result, the system will produce energy spectra and topological distribution of soft X-ray radiation. The advanced software was developed in order to perform complex system startup and monitoring of hardware units. Using the array of two one-dimensional GEM detectors it will be possible to perform tomographic reconstruction of plasma impurities radiation in the SXR region.

  18. Design of data acquisition system for GEM detector

    International Nuclear Information System (INIS)

    Lu Jianliang; Chen Ziyu; Shen Ji; Jin Xi

    2011-01-01

    It describes the design and realization of the USB 2.0 high speed data acquisition devise which is used in the readout electronics of the GEM (gas electron multiplier) detector. By using of the USB Microcontroller EZ-USB FX2 CY7C68013A, high speed ADC and FPGA, high-speed data rate of data acquisition and transmission was realized. The data rate reaches to 20 MByte/s, meeting the requirements of data acquisition and transmission of the detector. (authors)

  19. The design of the electronic system on neutron beam monitor based on GEM

    International Nuclear Information System (INIS)

    Zuo Min; Zhuang Bao'an; Zhao Yubin; Chen Shaojia; Wang Na; Zhang Hongyu; Zhao Jingwei

    2012-01-01

    The Neutron Beam Monitor - a GEM based system used to monitor the neutron beams in real time - is introduced. The electronic parts are described in details, including the principles of the circuit, the system structure, the design of the Daughterboard and the logic and algorithm of the FPGA on the Monitor board. The test results are also given out in the final. (authors)

  20. Development of the GEM-TPC X-ray Polarimeter with the Scalable Readout System

    Directory of Open Access Journals (Sweden)

    Kitaguchi Takao

    2018-01-01

    Full Text Available We have developed a gaseous Time Projection Chamber (TPC containing a single-layered foil of a gas electron multiplier (GEM to open up a new window on cosmic X-ray polarimetry in the 2–10 keV band. The micro-pattern TPC polarimeter in combination with the Scalable Readout System produced by the RD51 collaboration has been built as an engineering model to optimize detector parameters and improve polarimeter sensitivity. The polarimeter was characterized with unpolarized X-rays from an X-ray generator in a laboratory and polarized X-rays on the BL32B2 beamline at the SPring-8 synchrotron radiation facility. Preliminary results show that the polarimeter has a comparable modulation factor to a prototype of the flight one.

  1. Gems [Guardian Environmental Monitoring System] keeps a continuous eye on gamma-ray emissions

    International Nuclear Information System (INIS)

    Gould, J.L.

    1986-01-01

    To enable electricity utilities to demonstrate the very low release rates of radiation emitters from nuclear power stations into the environment, Gems (Guardian Environmental Monitoring System) has been developed. The units have been installed as emergency plume monitors round the perimeter of several British power stations and can be connected to windspeed and direction instrumentation to provide on-line activity release data. (UK)

  2. CMS Muon System Phase 2 Upgrade with triple-GEM detectors

    CERN Document Server

    Salva Diblen, Sinem

    2015-01-01

    The Compact Muon Solenoid (CMS) detector installed at the CERN Large Hadron Collider (LHC) has an extensive muon system which provides information simultaneously for identification, track reconstruction and triggering of muons. As a consequence of the extreme particle rate and high integrated charge, the essentiality to upgrade the LHC has given rise to the High Luminosity phase of the LHC (HL-LHC) project so that the CMS muon system will be upgraded with superior technological challenges. The CMS GEM collaboration offers a solution to equip the high-eta region of the muon system for Phase 2 (after the year 2017) with large-area triple-layer Gas Electron Multiplier (GEM) detectors, since GEMs have the ability to provide robust and redundant tracking and triggering functions with an excellent spatial resolution of order 100 micron and a high particle rate capability, with a close to 100pct detection efficiency. In this contribution, the present status of the triple-GEM project will be reviewed, and the signifi...

  3. Physics motivations and expected performance of the CMS muon system upgrade with triple-GEM detectors

    CERN Document Server

    Venditti, Rosamaria; Abbrescia, Marcello; Aleksandrov, Andrey B; Benussi, Luigi; Beni, Noemi; Bianco, Stefano; Calabria, Cesare; Caponero, Michele; Hernandez, Alfredo Martin Castaneda; Cavallo, Francesca; Colafranceschi, Stefano; Lentdecker, Gilles De; Oliveira, R; Guiducci, Luigi; Hoepfner, Kerstin; Iaydjiev, P S; Korytov, Andrey; Krutelyov, Slava; Kumar, A; Lee, Jason; Litov, L; Loddo, F; Maggi, M; Marchioro, Alessandro; Mitselmakher, Guenakh; Mohanty, Ajit Kumar; Molnar, J; Naimuddin, Md; Nuzzo, S; Pant, Lalit; Paolucci, Pierluigi; Pavlov, Borislav; Piccolo, Davide; Postema, Hans; Raffaella, Radogna; Ranieri, A; Riccardi, C; Rodozov, Mircho; Safonov, Alexei; Saviano, Giovanna; Sharma, Archana; Tytgat, Michael; Vitulo, Paolo; Colaleo, Anna; Caputo, Claudio; Errico, Filippo; Dildick, Sven; Vai, Ilaria; Magnani, Alice; Verwilligen, Piet; Altieri, Palma; Aspell, Paul; Giacomelli, Paolo; Braibant, Sylvie; Buontempo, S; Kamon, Teruki; Tatarinov, A; Celik, Ali; Gilmore, Jason; Flanagan, Will; Khotilovich, Vadim; Czellar, S; Fenyvesi, A; Jozsef Molnar@Cern Ch, Jozsef; Barria, P; Korntheuer, Michael; Lenzi, T; Maerschalk, T; Verhagen, E; Yang, Yifan; Yonamine, R; Zenoni, F; Merlin, J; Dorney, B; Garcia, A Conde; Dabrowski, M; Marinov, A; Oliveri, E; Baranac, A Puig; Ropelewski, Leszek; Bos, J; Bally, S; Stenis, M Van; Ferry, S; Rodrigues, A; Robertis, G De; Christiansen, J; Hohlmann, M; Bhopatkar, V; Mohapatra, A; Zhang, A; Hauser, J; Tuuva, Tuure; Talvitie, J; Passeggio, G; Cassese, F; Banerjee, S; Majumdar, N; Mukhopadhyay, Supratik; Roychowdhur, S; Salva, S; Zaganidis, N; Cimmino, A; Cauwenbergh, S; Bouhali, O; Akl, M Abi; Sturdy, J; Karchin, P; Gutierrez, A; Hadjiiska, R; Aleksandrov, Aleksandar; Rashevski, G; Rodozov, M; Shopova, M; Sultanov, G; Acosta, D; Barashko, V; Furic, I; Madorsky, A; Korytov, A; Mitselmakher, G; Raffone, G; Radi, A; Assran, Y; Aboamer, O; Ahmad, A; Ahmed, W; Awan, I; Hoorani, H; Muhammad, S; Sharma, R; Geonmo, R; Ryu, M S; Park, I; Jeng, Y C; Choi, M; Golovtsov, V; Volkov, S; Vorobyev, A; Choi, S; Guilloux, F; Philipps, B

    2015-01-01

    For the LHC High Luminosity phase (HL-LHC) the CMS GEM Collaboration is planning to in- stall new large size triple-GEM detectors in the forward region of the muon system (1.5< j h |<2.2) of the CMS detector. The muon reconstruction with triple-GEM chambers information included have been successfully integrated in the official CMS software, allowing physics studies to be carried out. The new sub-detector will be able to cope the extreme particle rates expected in this region along with a high spatial resolution. The resulting benefit in terms of triggering and tracking capabilities has been studied: the expected improvement in the performance of the muon identification and track reconstruction as well as the expected improvement coming from the low- ering of the muon p T trigger tresholds will be presented. The contribution will review the status of the CMS upgrade project with the usage of GEM detector, discussing the trigger, the muon reconstruction performance and the impact on the physics analyses.

  4. Status of the Triple-GEM Project for the Upgrade of the CMS Muon System

    CERN Document Server

    Tytgat, Michael

    2013-01-01

    The GEMs for CMS collaboration is performing a feasibility study to install triple-GEM detectors in the forward region of the muon system ($1.6<\\eta<2.4$) of the CMS detector at the LHC. Such micro-pattern gas detectors are able to cope with the extreme particle rates that are expected in that region during the High Luminosity phase of the LHC. With their spatial resolution of order 100 micron GEMs would not only provide additional benefits in the CMS muon High Level Trigger, but also in the muon identification and track reconstruction, effectively combining tracking and triggering capabilities in one single device. The present status of the full project will be reviewed, highlighting all importants steps and achievements since the start of the R and D in 2009. Several small and full-size prototypes were constructed with different geometries and techniques. The baseline design of the triple-GEM detectorfor CMS will be described, along with the results from extensive test measurements of all prototypes ...

  5. Graphics gems

    CERN Document Server

    Heckbert, Paul S

    1994-01-01

    Graphics Gems IV contains practical techniques for 2D and 3D modeling, animation, rendering, and image processing. The book presents articles on polygons and polyhedral; a mix of formulas, optimized algorithms, and tutorial information on the geometry of 2D, 3D, and n-D space; transformations; and parametric curves and surfaces. The text also includes articles on ray tracing; shading 3D models; and frame buffer techniques. Articles on image processing; algorithms for graphical layout; basic interpolation methods; and subroutine libraries for vector and matrix algebra are also demonstrated. Com

  6. Fast data transmission from serial data acquisition for the GEM detector system

    Science.gov (United States)

    Kolasinski, Piotr; Pozniak, Krzysztof T.; Czarski, Tomasz; Byszuk, Adrian; Chernyshova, Maryna; Kasprowicz, Grzegorz; Krawczyk, Rafal D.; Wojenski, Andrzej; Zabolotny, Wojciech

    2015-09-01

    This article proposes new method of storing data and transferring it to PC in the X-ray GEM detector system. The whole process is performed by FPGA chips (Spartan-6 series from Xilinx). Comparing to previous methods, new approach allows to store much more data in the system. New, improved implementation of the communication algorithm significantly increases transfer rate between system and PC. In PC data is merged and processed by MATLAB. The structure of firmware implemented in the FPGAs is described.

  7. Commissioning and integration testing of the DAQ system for the CMS GEM upgrade

    CERN Document Server

    Castaneda Hernandez, Alfredo Martin

    2017-01-01

    The CMS muon system will undergo a series of upgrades in the coming years to preserve and extend its muon detection capabilities during the High Luminosity LHC.The first of these will be the installation of triple-foil GEM detectors in the CMS forward region with the goal of maintaining trigger rates and preserving good muon reconstruction, even in the expected harsh environment.In 2017 the CMS GEM project is looking to achieve a major milestone in the project with the installation of 5 super-chambers in CMS; this exercise will allow for the study of services installation and commissioning, and integration with the rest of the subsystems for the first time. An overview of the DAQ system will be given with emphasis on the usage during chamber quality control testing, commissioning in CMS, and integration with the central CMS system.

  8. Dst Index in the 2008 GEM Modeling Challenge - Model Performance for Moderate and Strong Magnetic Storms

    Science.gov (United States)

    Rastaetter, Lutz; Kuznetsova, Maria; Hesse, Michael; Chulaki, Anna; Pulkkinen, Antti; Ridley, Aaron J.; Gombosi, Tamas; Vapirev, Alexander; Raeder, Joachim; Wiltberger, Michael James; hide

    2010-01-01

    The GEM 2008 modeling challenge efforts are expanding beyond comparing in-situ measurements in the magnetosphere and ionosphere to include the computation of indices to be compared. The Dst index measures the largest deviations of the horizontal magnetic field at 4 equatorial magnetometers from the quiet-time background field and is commonly used to track the strength of the magnetic disturbance of the magnetosphere during storms. Models can calculate a proxy Dst index in various ways, including using the Dessler-Parker Sckopke relation and the energy of the ring current and Biot-Savart integration of electric currents in the magnetosphere. The GEM modeling challenge investigates 4 space weather events and we compare models available at CCMC against each other and the observed values of Ost. Models used include SWMF/BATSRUS, OpenGGCM, LFM, GUMICS (3D magnetosphere MHD models), Fok-RC, CRCM, RAM-SCB (kinetic drift models of the ring current), WINDMI (magnetosphere-ionosphere electric circuit model), and predictions based on an impulse response function (IRF) model and analytic coupling functions with inputs of solar wind data. In addition to the analysis of model-observation comparisons we look at the way Dst is computed in global magnetosphere models. The default value of Dst computed by the SWMF model is for Bz the Earth's center. In addition to this, we present results obtained at different locations on the Earth's surface. We choose equatorial locations at local noon, dusk (18:00 hours), midnight and dawn (6:00 hours). The different virtual observatory locations reveal the variation around the earth-centered Dst value resulting from the distribution of electric currents in the magnetosphere during different phases of a storm.

  9. The Triple-GEM Project for the Phase 2 Upgrade of the CMS Muon System

    CERN Document Server

    Tytgat, Michael

    2014-01-01

    In view of the high-luminosity phase of the LHC, the CMS Collaboration is considering the use of Gas Electron Multiplier (GEM) detector technology for the upgrade of its muon system in the forward region. With their ability to handle the extreme particle rates expected in that area, such micro-pattern gas detectors can sustain a high performance and redundant muon trigger system. At the same time, with their excellent spatial resolution, they can improve the muon track reconstruction and identification capabilities of the forward detector, effectively combining tracking and triggering functions in one single device. The present status of the CMS GEM project will be reviewed, highlighting importants steps and achievements since the start of the R and D activities in 2009. The baseline design of the triple-GEM detectors proposed for installation in different stations of the CMS muon endcap system will be described, along with the associated frontend electronics and data-acquisition system. The expected impact o...

  10. Comparison of the HadGEM2 climate-chemistry model against in situ and SCIAMACHY atmospheric methane data

    Directory of Open Access Journals (Sweden)

    G. D. Hayman

    2014-12-01

    Full Text Available Wetlands are a major emission source of methane (CH4 globally. In this study, we evaluate wetland emission estimates derived using the UK community land surface model (JULES, the Joint UK Land Earth Simulator against atmospheric observations of methane, including, for the first time, total methane columns derived from the SCIAMACHY instrument on board the ENVISAT satellite. Two JULES wetland emission estimates are investigated: (a from an offline run driven with Climatic Research Unit–National Centers for Environmental Prediction (CRU-NCEP meteorological data and (b from the same offline run in which the modelled wetland fractions are replaced with those derived from the Global Inundation Extent from Multi-Satellites (GIEMS remote sensing product. The mean annual emission assumed for each inventory (181 Tg CH4 per annum over the period 1999–2007 is in line with other recently published estimates. There are regional differences as the unconstrained JULES inventory gives significantly higher emissions in the Amazon (by ~36 Tg CH4 yr−1 and lower emissions in other regions (by up to 10 Tg CH4 yr−1 compared to the JULES estimates constrained with the GIEMS product. Using the UK Hadley Centre's Earth System model with atmospheric chemistry (HadGEM2, we evaluate these JULES wetland emissions against atmospheric observations of methane. We obtain improved agreement with the surface concentration measurements, especially at high northern latitudes, compared to previous HadGEM2 runs using the wetland emission data set of Fung et al. (1991. Although the modelled monthly atmospheric methane columns reproduce the large-scale patterns in the SCIAMACHY observations, they are biased low by 50 part per billion by volume (ppb. Replacing the HadGEM2 modelled concentrations above 300 hPa with HALOE–ACE assimilated TOMCAT output results in a significantly better agreement with the SCIAMACHY observations. The use of the GIEMS product to constrain the JULES

  11. Comparison of the HadGEM2 climate-chemistry model against in-situ and SCIAMACHY atmospheric methane data

    Science.gov (United States)

    Hayman, G. D.; O'Connor, F. M.; Dalvi, M.; Clark, D. B.; Gedney, N.; Huntingford, C.; Prigent, C.; Buchwitz, M.; Schneising, O.; Burrows, J. P.; Wilson, C.; Richards, N.; Chipperfield, M.

    2014-05-01

    Wetlands are a major emission source of methane (CH4) globally. In this study, we have evaluated wetland emission estimates derived using the UK community land surface model (JULES, the Joint UK Land Earth Simulator) against atmospheric observations of methane, including, for the first time, total methane columns derived from the SCIAMACHY instrument on board the ENVISAT satellite. Two JULES wetland emission estimates were investigated: (a) from an offline run driven with CRU-NCEP meteorological data and (b) from the same offline run in which the modelled wetland fractions were replaced with those derived from the Global Inundation Extent from Multi-Satellites (GIEMS) remote sensing product. The mean annual emission assumed for each inventory (181 Tg CH4 per annum over the period 1999-2007) is in line with other recently-published estimates. There are regional differences as the unconstrained JULES inventory gave significantly higher emissions in the Amazon and lower emissions in other regions compared to the JULES estimates constrained with the GIEMS product. Using the UK Hadley Centre's Earth System model with atmospheric chemistry (HadGEM2), we have evaluated these JULES wetland emissions against atmospheric observations of methane. We obtained improved agreement with the surface concentration measurements, especially at northern high latitudes, compared to previous HadGEM2 runs using the wetland emission dataset of Fung (1991). Although the modelled monthly atmospheric methane columns reproduced the large-scale patterns in the SCIAMACHY observations, they were biased low by 50 part per billion by volume (ppb). Replacing the HadGEM2 modelled concentrations above 300 hPa with HALOE-ACE assimilated TOMCAT output resulted in a significantly better agreement with the SCIAMACHY observations. The use of the GIEMS product to constrain JULES-derived wetland fraction improved the description of the wetland emissions in JULES and gave a good description of the seasonality

  12. Comparison of the HadGEM2 climate-chemistry model against in situ and SCIAMACHY atmospheric methane data

    Science.gov (United States)

    Hayman, G. D.; O'Connor, F. M.; Dalvi, M.; Clark, D. B.; Gedney, N.; Huntingford, C.; Prigent, C.; Buchwitz, M.; Schneising, O.; Burrows, J. P.; Wilson, C.; Richards, N.; Chipperfield, M.

    2014-12-01

    Wetlands are a major emission source of methane (CH4) globally. In this study, we evaluate wetland emission estimates derived using the UK community land surface model (JULES, the Joint UK Land Earth Simulator) against atmospheric observations of methane, including, for the first time, total methane columns derived from the SCIAMACHY instrument on board the ENVISAT satellite. Two JULES wetland emission estimates are investigated: (a) from an offline run driven with Climatic Research Unit-National Centers for Environmental Prediction (CRU-NCEP) meteorological data and (b) from the same offline run in which the modelled wetland fractions are replaced with those derived from the Global Inundation Extent from Multi-Satellites (GIEMS) remote sensing product. The mean annual emission assumed for each inventory (181 Tg CH4 per annum over the period 1999-2007) is in line with other recently published estimates. There are regional differences as the unconstrained JULES inventory gives significantly higher emissions in the Amazon (by ~36 Tg CH4 yr-1) and lower emissions in other regions (by up to 10 Tg CH4 yr-1) compared to the JULES estimates constrained with the GIEMS product. Using the UK Hadley Centre's Earth System model with atmospheric chemistry (HadGEM2), we evaluate these JULES wetland emissions against atmospheric observations of methane. We obtain improved agreement with the surface concentration measurements, especially at high northern latitudes, compared to previous HadGEM2 runs using the wetland emission data set of Fung et al. (1991). Although the modelled monthly atmospheric methane columns reproduce the large-scale patterns in the SCIAMACHY observations, they are biased low by 50 part per billion by volume (ppb). Replacing the HadGEM2 modelled concentrations above 300 hPa with HALOE-ACE assimilated TOMCAT output results in a significantly better agreement with the SCIAMACHY observations. The use of the GIEMS product to constrain the JULES-derived wetland

  13. Study of reconstruction methods for a time projection chamber with GEM gas amplification system

    International Nuclear Information System (INIS)

    Diener, R.

    2006-12-01

    A new e + e - linear collider with an energy range up to 1TeV is planned in an international collaboration: the International Linear Collider (ILC). This collider will be able to do precision measurements of the Higgs particle and of physics beyond the Standard Model. In the Large Detector Concept (LDC) - which is one proposal for a detector at the ILC - a Time Projection Chamber (TPC) is foreseen as the main tracking device. To meet the requirements on the resolution and to be able to work in the environment at the ILC, the application of new gas amplification technologies in the TPC is necessary. One option is an amplification system based on Gas Electron Multipliers (GEMs). Due to the - in comparison with older technologies - small spatial width of the signals, this technology poses new requirements on the readout structures and the reconstruction methods. In this work, the performance and the systematics of different reconstruction methods have been studied, based on data measured with a TPC prototype in high magnetic fields of up to 4T and data from a Monte Carlo simulation. The latest results of the achievable point resolution are presented and their limitations have been investigated. (orig.)

  14. Study of reconstruction methods for a time projection chamber with GEM gas amplification system

    Energy Technology Data Exchange (ETDEWEB)

    Diener, R.

    2006-12-15

    A new e{sup +}e{sup -} linear collider with an energy range up to 1TeV is planned in an international collaboration: the International Linear Collider (ILC). This collider will be able to do precision measurements of the Higgs particle and of physics beyond the Standard Model. In the Large Detector Concept (LDC) - which is one proposal for a detector at the ILC - a Time Projection Chamber (TPC) is foreseen as the main tracking device. To meet the requirements on the resolution and to be able to work in the environment at the ILC, the application of new gas amplification technologies in the TPC is necessary. One option is an amplification system based on Gas Electron Multipliers (GEMs). Due to the - in comparison with older technologies - small spatial width of the signals, this technology poses new requirements on the readout structures and the reconstruction methods. In this work, the performance and the systematics of different reconstruction methods have been studied, based on data measured with a TPC prototype in high magnetic fields of up to 4T and data from a Monte Carlo simulation. The latest results of the achievable point resolution are presented and their limitations have been investigated. (orig.)

  15. Test and improvement of readout system based on APV25 chip for GEM detector

    International Nuclear Information System (INIS)

    Hu Shouyang; Jian Siyu; Zhou Jing; Shan Chao; Li Xinglong; Li Xia; Li Xiaomei; Zhou Yi

    2014-01-01

    Gas electron multiplier (GEM) is the most promising position sensitive gas detector. The new generation of readout electronics system includes APV25 front-end card, multi-purpose digitizer (MPD), VME controller and Linux-based acquisition software DAQ. The construction and preliminary test of this readout system were finished, and the ideal data with the system working frequency of 40 MHz and 20 MHz were obtained. The long time running test shows that the system has a very good time-stable ability. Through optimizing the software configuration and improving hardware quality, the noise level was reduced, and the signal noise ratio was improved. (authors)

  16. A 40 GByte/s read-out system for GEM

    International Nuclear Information System (INIS)

    Bowden, M.; Carrel, J.; Dorenbosch, J.; Kapoor, V.

    1994-04-01

    The preliminary design of the read-out system for the GEM (Gammas, Electrons, Muons) detector at the Superconducting Super Collider is presented. The system reads all digitized data from the detector data sources at a Level 1 trigger rate of up to 100 kHz. A total read-out bandwidth of 40 GBytes/s is available. Data are stored in buffers that are accessible for further event filtering by an on-line, processor farm. Data are transported to the farm only as they are needed by the higher-level trigger algorithms, leading to a reduced bandwidth requirement in the Data Acquisition System

  17. GEM Building Taxonomy (Version 2.0)

    Science.gov (United States)

    Brzev, S.; Scawthorn, C.; Charleson, A.W.; Allen, L.; Greene, M.; Jaiswal, Kishor; Silva, V.

    2013-01-01

    This report documents the development and applications of the Building Taxonomy for the Global Earthquake Model (GEM). The purpose of the GEM Building Taxonomy is to describe and classify buildings in a uniform manner as a key step towards assessing their seismic risk, Criteria for development of the GEM Building Taxonomy were that the Taxonomy be relevant to seismic performance of different construction types; be comprehensive yet simple; be collapsible; adhere to principles that are familiar to the range of users; and ultimately be extensible to non-buildings and other hazards. The taxonomy was developed in conjunction with other GEM researchers and builds on the knowledge base from other taxonomies, including the EERI and IAEE World Housing Encyclopedia, PAGER-STR, and HAZUS. The taxonomy is organized as a series of expandable tables, which contain information pertaining to various building attributes. Each attribute describes a specific characteristic of an individual building or a class of buildings that could potentially affect their seismic performance. The following 13 attributes have been included in the GEM Building Taxonomy Version 2.0 (v2.0): 1.) direction, 2.)material of the lateral load-resisting system, 3.) lateral load-resisting system, 4.) height, 5.) date of construction of retrofit, 6.) occupancy, 7.) building position within a block, 8.) shape of the building plan, 9.) structural irregularity, 10.) exterior walls, 11.) roof, 12.) floor, 13.) foundation system. The report illustrates the pratical use of the GEM Building Taxonomy by discussing example case studies, in which the building-specific characteristics are mapped directly using GEM taxonomic attributes and the corresponding taxonomic string is constructed for that building, with "/" slash marks separating attributes. For example, for the building shown to the right, the GEM Taxonomy string is: DX1/MUR+CLBRS+MOCL2/LWAL3/

  18. An Entrepreneurial Well-being Model based on GEM Data for Spain

    Directory of Open Access Journals (Sweden)

    José Manuel Sáiz-Álvarez

    2014-03-01

    Full Text Available The Economics of Happiness is one of the research areas of greatest growth in recent years. Throughout this work, a venture based model in which satisfaction of Spanish entrepreneurs with their professional life is performed. We analyze the responses of 9,989 entrepreneurs using data from the Global Entrepreneurship Monitor (GEM, and six hypothesis are discussed. The results show that, for the Spanish case, there is a strong consistency in the results the opportunity entrepreneurs present greater satisfaction than necessity entrepreneurs.

  19. Modeling radiation belt electron dynamics during GEM challenge intervals with the DREAM3D diffusion model

    Science.gov (United States)

    Tu, Weichao; Cunningham, G. S.; Chen, Y.; Henderson, M. G.; Camporeale, E.; Reeves, G. D.

    2013-10-01

    a response to the Geospace Environment Modeling (GEM) "Global Radiation Belt Modeling Challenge," a 3D diffusion model is used to simulate the radiation belt electron dynamics during two intervals of the Combined Release and Radiation Effects Satellite (CRRES) mission, 15 August to 15 October 1990 and 1 February to 31 July 1991. The 3D diffusion model, developed as part of the Dynamic Radiation Environment Assimilation Model (DREAM) project, includes radial, pitch angle, and momentum diffusion and mixed pitch angle-momentum diffusion, which are driven by dynamic wave databases from the statistical CRRES wave data, including plasmaspheric hiss, lower-band, and upper-band chorus. By comparing the DREAM3D model outputs to the CRRES electron phase space density (PSD) data, we find that, with a data-driven boundary condition at Lmax = 5.5, the electron enhancements can generally be explained by radial diffusion, though additional local heating from chorus waves is required. Because the PSD reductions are included in the boundary condition at Lmax = 5.5, our model captures the fast electron dropouts over a large L range, producing better model performance compared to previous published results. Plasmaspheric hiss produces electron losses inside the plasmasphere, but the model still sometimes overestimates the PSD there. Test simulations using reduced radial diffusion coefficients or increased pitch angle diffusion coefficients inside the plasmasphere suggest that better wave models and more realistic radial diffusion coefficients, both inside and outside the plasmasphere, are needed to improve the model performance. Statistically, the results show that, with the data-driven outer boundary condition, including radial diffusion and plasmaspheric hiss is sufficient to model the electrons during geomagnetically quiet times, but to best capture the radiation belt variations during active times, pitch angle and momentum diffusion from chorus waves are required.

  20. Graphics gems

    CERN Document Server

    Glassner, Andrew S

    1993-01-01

    ""The GRAPHICS GEMS Series"" was started in 1990 by Andrew Glassner. The vision and purpose of the Series was - and still is - to provide tips, techniques, and algorithms for graphics programmers. All of the gems are written by programmers who work in the field and are motivated by a common desire to share interesting ideas and tools with their colleagues. Each volume provides a new set of innovative solutions to a variety of programming problems.

  1. Analysis of Beam Test Data from UTA GEM Prototype Chambers with One-Bit Digital Readout System

    Science.gov (United States)

    Pray, Danrae

    2012-03-01

    Gas Electron Multiplier (GEM) technology is currently a strong candidate for a Digital Hadron Calorimeter to be implemented in an experiment in future accelerators such as the International Linear Collider. The University of Texas at Arlington High Energy Physics Group has been developing prototype GEM detectors which contain two layers of GEM foils. The team performed a two week long beam test of four prototype chambers with dimensions 30cm by 30cm at Fermi National Accelerator Laboratory in August of 2011. Three of these chambers were equipped with the one bit DCAL chip readout system jointly developed by Argonne National Laboratory and Fermi National Accelerator Laboratory teams. In this talk, we give an updated report of the results of the test beam data analysis of the GEM prototype detector functionality, responses to various particle types, efficiency dependence on threshold and high voltage, as well as the current/future studies that the UTA team is performing with the GEM detectors and DCAL readout system.

  2. Graphics Gems III IBM version

    CERN Document Server

    Kirk, David

    1994-01-01

    This sequel to Graphics Gems (Academic Press, 1990), and Graphics Gems II (Academic Press, 1991) is a practical collection of computer graphics programming tools and techniques. Graphics Gems III contains a larger percentage of gems related to modeling and rendering, particularly lighting and shading. This new edition also covers image processing, numerical and programming techniques, modeling and transformations, 2D and 3D geometry and algorithms,ray tracing and radiosity, rendering, and more clever new tools and tricks for graphics programming. Volume III also includes a

  3. First Results of the PixelGEM Central Tracking System for COMPASS

    CERN Document Server

    Austregesilo, Alexander; Ketzer, Bernhard; Konorov, Igor; Kramer, Markus; Mann, Alexander; Nagel, Thiemo; Paul, Stephan; Uhl, Sebastian

    2009-01-01

    For its physics program with a high-intensity hadron beam of up to 2e7 particles/s, the COMPASS experiment at CERN requires tracking of charged particles scattered by very small angles with respect to the incident beam direction. While good resolution in time and space is mandatory, the challenge is imposed by the high beam intensity, requiring radiation-hard detectors which add very little material to the beam path in order to minimize secondary interactions. To this end, a set of triple-GEM detectors with a hybrid readout structure consisting of pixels in the beam region and 2-D strips in the periphery was designed and built. Successful prototype tests proved the performance of this new detector type, showing both extraordinary high rate capability and detection efficiency. The amplitude information allowed to achieve spatial resolutions about a factor of 10 smaller than the pitch and a time resolution close to the theoretical limit imposed by the layout. The PixelGEM central tracking system consisting of f...

  4. The optimisation of a water distribution system using Bentley WaterGEMS software

    Directory of Open Access Journals (Sweden)

    Świtnicka Karolina

    2017-01-01

    Full Text Available The proper maintenance of water distribution systems (WDSs requires from operators multiple actions in order to ensure optimal functioning. Usually, all requirements should be adjusted simultaneously. Therefore, the decision-making process is often supported by multi-criteria optimisation methods. Significant improvements of exploitation conditions of WDSs functioning can be achieved by connecting small water supply networks into group systems. Among many potential tools supporting advanced maintenance and management of WDSs, significant improvements have tools that can find the optimal solution by the implemented mechanism of metaheuristic methods, such as the genetic algorithm. In this paper, an exemplary WDS functioning optimisation is presented, in relevance to a group water supply system. The action range of optimised parameters included: maximisation of water flow velocity, regulation of pressure head, minimisation of water retention time in a network (water age and minimisation of pump energy consumption. All simulations were performed in Bentley WaterGEMS software.

  5. Estimating Fallout Building Attributes from Architectural Features and Global Earthquake Model (GEM) Building Descriptions

    Energy Technology Data Exchange (ETDEWEB)

    Dillon, Michael B. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Kane, Staci R. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2017-03-01

    A nuclear explosion has the potential to injure or kill tens to hundreds of thousands (or more) of people through exposure to fallout (external gamma) radiation. Existing buildings can protect their occupants (reducing fallout radiation exposures) by placing material and distance between fallout particles and individuals indoors. Prior efforts have determined an initial set of building attributes suitable to reasonably assess a given building’s protection against fallout radiation. The current work provides methods to determine the quantitative values for these attributes from (a) common architectural features and data and (b) buildings described using the Global Earthquake Model (GEM) taxonomy. These methods will be used to improve estimates of fallout protection for operational US Department of Defense (DoD) and US Department of Energy (DOE) consequence assessment models.

  6. 2008 GEM Modeling Challenge: Metrics Study of the Dst Index in Physics-Based Magnetosphere and Ring Current Models and in Statistical and Analytic Specifications

    Science.gov (United States)

    Rastaetter, L.; Kuznetsova, M.; Hesse, M.; Pulkkinen, A.; Glocer, A.; Yu, Y.; Meng, X.; Raeder, J.; Wiltberger, M.; Welling, D.; hide

    2011-01-01

    In this paper the metrics-based results of the Dst part of the 2008-2009 GEM Metrics Challenge are reported. The Metrics Challenge asked modelers to submit results for 4 geomagnetic storm events and 5 different types of observations that can be modeled by statistical or climatological or physics-based (e.g. MHD) models of the magnetosphere-ionosphere system. We present the results of over 25 model settings that were run at the Community Coordinated Modeling Center (CCMC) and at the institutions of various modelers for these events. To measure the performance of each of the models against the observations we use comparisons of one-hour averaged model data with the Dst index issued by the World Data Center for Geomagnetism, Kyoto, Japan, and direct comparison of one-minute model data with the one-minute Dst index calculated by the United States Geologic Survey (USGS).

  7. Application of the GEM Inventory Data Capture Tools for Dynamic Vulnerability Assessment and Recovery Modelling

    Science.gov (United States)

    Verrucci, Enrica; Bevington, John; Vicini, Alessandro

    2014-05-01

    A set of open-source tools to create building exposure datasets for seismic risk assessment was developed from 2010-13 by the Inventory Data Capture Tools (IDCT) Risk Global Component of the Global Earthquake Model (GEM). The tools were designed to integrate data derived from remotely-sensed imagery, statistically-sampled in-situ field data of buildings to generate per-building and regional exposure data. A number of software tools were created to aid the development of these data, including mobile data capture tools for in-field structural assessment, and the Spatial Inventory Data Developer (SIDD) for creating "mapping schemes" - statistically-inferred distributions of building stock applied to areas of homogeneous urban land use. These tools were made publically available in January 2014. Exemplar implementations in Europe and Central Asia during the IDCT project highlighted several potential application areas beyond the original scope of the project. These are investigated here. We describe and demonstrate how the GEM-IDCT suite can be used extensively within the framework proposed by the EC-FP7 project SENSUM (Framework to integrate Space-based and in-situ sENSing for dynamic vUlnerability and recovery Monitoring). Specifically, applications in the areas of 1) dynamic vulnerability assessment (pre-event), and 2) recovery monitoring and evaluation (post-event) are discussed. Strategies for using the IDC Tools for these purposes are discussed. The results demonstrate the benefits of using advanced technology tools for data capture, especially in a systematic fashion using the taxonomic standards set by GEM. Originally designed for seismic risk assessment, it is clear the IDCT tools have relevance for multi-hazard risk assessment. When combined with a suitable sampling framework and applied to multi-temporal recovery monitoring, data generated from the tools can reveal spatio-temporal patterns in the quality of recovery activities and resilience trends can be

  8. Analysis of data recorded by the LCTPC equipped with a two layer GEM-system

    CERN Document Server

    Ljunggren, M

    2012-01-01

    wire based readout. The prototype TPC is placed in a 1 Tesla magnet at DESY and tested using an electron beam. Analyses of data taken during two different measurement series, in 2009 and 2010, are presented here. The TPC was instrumented with a two layer GEM system and read out using modified electronics from the ALICE experiment, including the programmable charge sensitive preamp-shaper PCA16. The PCA16 chip has a number of programmable parameters which allows studies to determine the settings optimal to the final TPC. Here, the impact of the shaping time on the space resolution in the drift direction was studied. It was found that a shaping time of 60 ns is the b...

  9. ARTROC—a readout ASIC for GEM-based full-field XRF imaging system

    Science.gov (United States)

    Fiutowski, T.; Koperny, S.; Łach, B.; Mindur, B.; Świentek, K.; Wiącek, P.; Dąbrowski, W.

    2017-12-01

    In the paper we report on development of an Application Specific Integrated Circuit (ASIC), called ARTROC, being part of a full-field X-ray fluorescence spectroscopy (XRF) imaging system equipped with a standard three stage Gas Electron Multiplier (GEM) detector of 10×10 cm2 area. The ARTROC consists of 64 independent channels, allowing for simultaneous recording of the amplitudes (energy sub-channel) and time stamps (timing sub-channel) of incoming signals. Thanks to the implemented token-based read out of derandomizing buffers, the ASIC also provides data sparsification and full zero suppression. Reconstruction of the hit positions is performed in an external data acquisition system by matching the time stamps of signals recorded in X- and Y-strips. The amplitude information is used for centre of gravity finding in clusters of signals on neighbouring strips belonging to the same detection events. The ASIC could work in one of six gain modes and one of two speed modes. In a slower mode the maximum count rate per channel is 105/s while in a faster mode it is three times higher. The ARTROC comprises also input protection circuits against possible random discharges inside active detector volume, so it can be used without any additional input components. The ASIC has been designed in 350 nm CMOS process. The basic functionality and parameters have been evaluated using the testability functions implemented in the ASIC design. The ASIC has been also tested in a fully equipped GEM detector set-up with X-rays source.

  10. Ozone observations over the UAE and their analysis with GEM-AQ model

    Science.gov (United States)

    Majeed, Tariq; Kaminski, Jacek; Iqbal, Mazhar; Abbasi, Naveed; Lootah, Nadia; Struzewska, Joanna; Durka, Pawel

    A study of ozone climatology in the UAE began in 2006 with a couple of ozone sounding experiments to the measure the vertical profiles of ozone and their analysis by using the Global Environmental Multiscale - Air Quality (GEM-AQ) model. The purpose of this study was to gain insight into the chemical and dynamical structures in the atmosphere of this unique subtropical location (latitude 24.45N; longitude 54.22E). Ozone sounding with balloon-borne ECC ozonesonde has been continued since 2006. In this paper, we present ozone profiles throughout the troposphere and the stratosphere characterizing the wet (January - April) and dry (May - August) seasons of 2013 over the UAE. Preliminary results of wet season profiles indicate that the stratospheric ozone is quite stable while thick polluted layers confined to the lower tropospheric heights, showing enhancements in ozone contents. The amount of tropospheric ozone which is transported from the stratosphere by dynamical processes, although not well known, shows considerable variation both geographically and seasonally. Excessive values of ozone mixing ratios in the range 50 - 55 ppb near the ground are observed. These values are 20 to 30% larger than those observed at nearby sounding stations like New Delhi (India) and Esfahan (Iran) using the same technique. The surface ozone in the dry season is observed to be even larger compared to the wet season exceeding 100 ppb on occasions. The difference in these values probably reflects the elevated levels of air pollution due to petrochemicals and automobile emissions in the UAE. We will present ECC sounding data and GEM-AQ results including a discussion on the high levels of surface ozone responsible for contaminating the air quality in the UAE. This work is supported by National Research Foundation, UAE.

  11. Development of the DAQ System of Triple-GEM Detectors for the CMS Muon Spectrometer Upgrade at LHC

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00387583

    The Gas Electron Multiplier (GEM) upgrade project aims at improving the performance of the muon spectrometer of the Compact Muon Solenoid (CMS) experiment which will suffer from the increase in luminosity of the Large Hadron Collider (LHC). After a long technical stop in 2019-2020, the LHC will restart and run at a luminosity of 2 × 1034 cm−2 s−1, twice its nominal value. This will in turn increase the rate of particles to which detectors in CMS will be exposed and affect their performance. The muon spectrometer in particular will suffer from a degraded detection efficiency due to the lack of redundancy in its most forward region. To solve this issue, the GEM collaboration proposes to instrument the first muon station with Triple-GEM detectors, a technology which has proven to be resistant to high fluxes of particles. Within the GEM collaboration, the Data Acquisition (DAQ) subgroup is in charge of the development of the electronics and software of the DAQ system of the detectors. This thesis presents th...

  12. The Triple GEM Detector Control System for CMS forward muon spectrometer upgrade

    OpenAIRE

    CMS Collaboration; Canelli, Florencia; Kilminster, Benjamin; Aarestad, Thea; Caminada, Lea; de Cosa, Annapaoloa; Del Burgo, Riccardo; Donato, Silvio; Galloni, Camilla; Hinzmann, Andreas; Hreus, Tomas; Ngadiuba, Jennifer; Pinna, Deborah; Rauco, Giorgia; Robmann, Peter

    2017-01-01

    The CMS experiment at LHC will upgrade its forward muon spectrometer by incorporating Triple-GEM detectors. This upgrade referred to as GEM Endcap (GE1/1), consists of adding two back-to-back Triple-GEM detectors in front of the existing Cathode Strip Chambers (CSC) in the innermost ring of the endcap muon spectrometer. Before the full installation of 144 detectors in 2019–2020, CMS will first install ten single chamber prototypes during the early 2017. This pre-installation is referred as th...

  13. GEM-Selektor geochemical modeling package: revised algorithm and GEMS3K numerical kernel for coupled simulation codes

    OpenAIRE

    Kulik D. A.; Wagner T.; Dmytrieva S. V.; Kosakowski G.; Hingerl F. F.; Chudnenko K. V.; Berner U. R.

    2013-01-01

    Reactive mass transport (RMT) simulation is a powerful numerical tool to advance our understanding of complex geochemical processes and their feedbacks in relevant subsurface systems. Thermodynamic equilibrium defines the baseline for solubility chemical kinetics and RMT in general. Efficient RMT simulations can be based on the operator splitting approach where the solver of chemical equilibria is called by the mass transport part for each control volume whose composition temperature or press...

  14. The Australian bushfires of February 2009: MIPAS observations and GEM-AQ model results

    Directory of Open Access Journals (Sweden)

    N. Glatthor

    2013-02-01

    Full Text Available Starting on 7 February 2009, southeast Australia was devastated by large bushfires, which burned an area of about 3000 km2 on this day alone. This event was extraordinary, because a large number of combustion products were transported into the uppermost troposphere and lower stratosphere within a few days. Various biomass burning products released by the fire were observed by the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS on the Envisat satellite. We tracked the plume using MIPAS C2H2, HCN and HCOOH single-scan measurements on a day-to-day basis. The measurements were compared with a high-resolution model run of the Global Environmental Multiscale Air Quality (GEM-AQ model. Generally there is good agreement between the spatial distribution of measured and modelled pollutants. Both MIPAS and GEM-AQ show a fast southeastward transport of the pollutants to New Zealand within one day. During the following 3–4 days, the plume remained northeastward of New Zealand and was located at altitudes of 15 to 18 km. Thereafter its lower part was transported eastward, followed by westward transport of its upper part. On 17 February the eastern part had reached southern South America and on 20 February the central South Atlantic. On the latter day a second relic of the plume was observed moving eastward above the South Pacific. Between 20 February and the first week of March, the upper part of the plume was transported westward over Australia and the Indian Ocean towards southern Africa. First evidence for entry of the pollutants into the stratosphere was found in MIPAS data of 11 February, followed by larger amounts on 17 February and the days thereafter. From MIPAS data, C2H2/HCN and HCOOH/HCN enhancement ratios of 0.76 and 2.16 were calculated for the first days after the outbreak of the fires, which are considerably higher than the emission ratios assumed for the model run and at

  15. Complete Tem-Tomography: 3D Structure of Gems Cluster

    Science.gov (United States)

    Matsuno, J.; Miyake, A.; Tsuchiyama, A.; Messenger, S.; Nakamura-Messenger, K.

    2015-01-01

    GEMS (glass with embedded metal and sulfide) grains in interplanetary dust particles (IDPs) are considered to be one of the ubiquitous and fundamental building blocks of solids in the Solar System. They have been considered to be interstellar silicate dust that survived various metamorphism or alteration processes in the protoplanetary disk but the elemental and isotopic composition measurements suggest that most of them have been formed in the protoplanetary disk as condensates from high temperature gas. This formation model is also supported by the formation of GEMS-like grains with respect to the size, mineral assemblage, texture and infrared spectrum by condensation experiments from mean GEMS composition materials. Previous GEMS studies were performed only with 2D observation by transmission electron microscopy (TEM) or scanning TEM (STEM). However, the 3D shape and structure of GEMS grains and the spatial distribution of Fe/FeS's has critical information about their formation and origin. Recently, the 3D structure of GEMS grains in ultrathin sections of cluster IDPs was revealed by electron tomography using a TEM/STEM (JEM-2100F, JEOL). However, CT images of thin sections mounted on Cu grids acquired by conventional TEM-tomography are limited to low tilt angles (e. g., less than absolute value of 75 deg. In fact, previous 3D TEM observations of GEMS were affected by some artifacts related to the limited tilt range in the TEM used. Complete tomographic images should be acquired by rotating the sample tilt angle over a range of more than absolute value of 80 deg otherwise the CT images lose their correct structures. In order to constrain the origin and formation process of GEMS grains more clearly, we performed complete electron tomography for GEMS grains. Here we report the sample preparation method we have developed for this study, and the preliminary results.

  16. Use of Excel ion exchange equilibrium solver with WinGEMS to model and predict NPE distribution in the Mead/Westvaco Evandale, TX, hardwood bleach plant

    Science.gov (United States)

    Christopher Litvay; Alan Rudie; Peter Hart

    2003-01-01

    An Excel spreadsheet developed to solve the ion-exchange equilibrium in wood pulps has been linked by dynamic data exchange to WinGEMS and used to model the non-process elements in the hardwood bleach plant of the Mead/Westvaco Evandale mill. Pulp and filtrate samples were collected from the diffusion washers and final wash press of the bleach plant. A WinGEMS model of...

  17. Study on the Development of Industry of Internet of Things Based on Competitive GEM Model in Fujian Province

    Directory of Open Access Journals (Sweden)

    Di Jun An

    2016-01-01

    Full Text Available Firstly, the basic theories of internet of things, competitive GEM model and industrial development in Fujian Province were studied in this paper. Then, the factors influencing the cultivation of industrial competitiveness of the internet of things was observed and finally the suggestions on enhancing the competitiveness of internet of things and strengthening the cultivation of talents of internet of things were put forward.

  18. GEM Technical Design Report

    International Nuclear Information System (INIS)

    1993-01-01

    The GEM collaboration was formed in June 1991 to develop a major detector for the SSC. The primary physics objectives of GEM are those central to the motivation for the SSC, to study high p T physics - exemplified by the search for Higgs bosons - and to search for new physics beyond the standard model. The authors present in this Technical Design Report (TDR) a detector with broad capabilities for the discovery and subsequent study of electroweak symmetry breaking, the origin of mass and flavor, and other physics requiring precise measurements of gammas, electrons, and muons - hence the name, GEM. In addition, as a design goal, they have taken care to provide the robustness needed to do the physics that requires high luminosity. Finally, good coverage and hermeticity allow the detection of missing transverse energy, E T . The GEM design emphasizes clean identification and high resolution measurement of the primary physics signatures for high p T physics. The approach is to make precise energy measurements that maximize the sensitivity to rare narrow resonances, to detect the elementary interaction products (quarks, leptons, and photons), and to build in the features required to reduce backgrounds

  19. GEM Technical Design Report

    Energy Technology Data Exchange (ETDEWEB)

    1993-07-31

    The GEM collaboration was formed in June 1991 to develop a major detector for the SSC. The primary physics objectives of GEM are those central to the motivation for the SSC, to study high p{sub T} physics - exemplified by the search for Higgs bosons - and to search for new physics beyond the standard model. The authors present in this Technical Design Report (TDR) a detector with broad capabilities for the discovery and subsequent study of electroweak symmetry breaking, the origin of mass and flavor, and other physics requiring precise measurements of gammas, electrons, and muons - hence the name, GEM. In addition, as a design goal, they have taken care to provide the robustness needed to do the physics that requires high luminosity. Finally, good coverage and hermeticity allow the detection of missing transverse energy, E{sub T}. The GEM design emphasizes clean identification and high resolution measurement of the primary physics signatures for high p{sub T} physics. The approach is to make precise energy measurements that maximize the sensitivity to rare narrow resonances, to detect the elementary interaction products (quarks, leptons, and photons), and to build in the features required to reduce backgrounds.

  20. ENED-GEM: A Conceptual Framework Model for Psychological Enjoyment Factors and Learning Mechanisms in Educational Games about the Environment

    Directory of Open Access Journals (Sweden)

    Kristoffer S. Fjællingsdal

    2017-06-01

    Full Text Available Based on a thorough review of psychological literature, this article seeks to develop a model of game enjoyment and environmental learning (ENvironmental EDucational Game Enjoyment Model, ENED-GEM and delineate psychological processes that might facilitate learning and inspire behavioral change from educational games about the environment. A critically acclaimed digital educational game about environmental issues (Fate of the World by Red Redemption/Soothsayer Games was used as a case study. Two hundred forty-nine reviews of the game from the popular gaming and reviewing platform known as Steam were analyzed by means of a thematic content analysis in order to identify key player enjoyment factors believed to be relevant to the process of learning from games, as well as to gain an understanding of positive and negative impressions about the game’s general content. The end results of the thematic analysis were measured up to the suggested ENED-GEM framework. Initial results generally support the main elements of the ENED-GEM, and future research into the importance of these individual core factors is outlined.

  1. Use of the HadGEM2 climate-chemistry model to investigate interannual variability in methane sources

    Science.gov (United States)

    Hayman, Garry; O'Connor, Fiona; Clark, Douglas; Huntingford, Chris; Gedney, Nicola

    2013-04-01

    . Qin, M. Manning, Z. Chen, M. Marquis, K.B. Averyt, M.Tignor and H.L. Miller (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, 2007. [3] Rigby, M., et al.: Renewed growth of atmospheric methane. Geophysical Research Letters, 35, L22805, doi:10.1029/2008GL036037, 2008. [4] Bousquet, P., et al.: Contribution of anthropogenic and natural sources to atmospheric methane variability, Nature, 443, 439-443, doi:10.1038/nature05132, 2006. [5] Collins, W. J., et al.: Development and evaluation of an Earth-System model - HadGEM2, Geoscientific Model Development, 4, 1051-1075, doi:10.5194/gmd-4-1051-2011, 2011. [6] Lamarque, J.-F., et al.: Historical (1850-2000) gridded anthropogenic and biomass burning emissions of reactive gases and aerosols: methodology and application, Atmospheric Chemistry and Physics, 10, 7017-7039, doi:10.5194/acp-10-7017-2010, 2010. [7] van der Werf, G. R., et al.: Global fire emissions and the contribution of deforestation, savanna, forest, agricultural, and peat fires (1997-2009), Atmospheric Chemistry and Physics, 10, 11707-11735, doi:10.5194/acp-10-11707-2010, 2010. [8] Fung, I., et al.: Three-dimensional model synthesis of the Global Methane Cycle. Journal of Geophysical Research, 96, 13,033-13,065, 1991. [9] Best, M. J., et al.: The Joint UK Land Environment Simulator (JULES), model description - Part 1: Energy and water fluxes, Geoscientific Model Development, 4, 677-699, doi:10.5194/gmd-4-677-2011, 2011. [10] Clark, D.B., et al.: The Joint UK Land Environment Simulator (JULES), Model description - Part 2: Carbon fluxes and vegetation. Geoscientific Model Development, 4, 701-722, doi:10.5194/gmd-4-701-2011, 2011. [11] Gedney, N., et al.: Climate feedback from wetland methane emissions. Geophysical Research Letters, 31, L20503, 2004.

  2. Construction and Performance of Large-Area Triple-GEM Prototypes for Future Upgrades of the CMS Forward Muon System

    CERN Document Server

    AUTHOR|(CDS)2068936; Marinov, A.; Zaganidis, N.; Ban, Y.; Cai, J.; Teng, H.; Mohapatra, A.; Moulik, T.; Abbrescia, M.; Colaleo, A.; de Robertis, G.; Loddo, F.; Maggi, M.; Nuzzo, S.; Tupputi, S.A.; Benussi, L.; Bianco, S.; Colafranceschi, S.; Piccolo, D.; Raffone, G.; Saviano, G.; Bagliesi, M.G.; Cecchi, R.; Magazzu, G.; Oliveri, E.; Turini, N.; Fruboes, T.; Abbaneo, D.; Armagnaud, C.; Aspell, P.; Bally, S.; Berzano, U.; Bos, J.; Bunkowski, K.; Chatelain, J.P.; Christiansen, J.; Conde Garcia, A.; David, E.; De Oliveira, R.; Duarte Pinto, S.; Ferry, S.; Formenti, F.; Franconi, L.; Marchioro, A.; Mehta, K.; Merlin, J.; Nemallapudi, M.V.; Postema, H.; Rodrigues, A.; Ropelewski, L.; Sharma, A.; Smilkjovic, N.; Villa, M.; Zientek, M.; Gutierrez, A.; Karchin, P.E.; Gnanvo, K.; Hohlmann, M.; Staib, M.J.

    2011-01-01

    At present, part of the forward RPC muon system of the CMS detector at the CERN LHC remains uninstrumented in the high-\\eta region. An international collaboration is investigating the possibility of covering the 1.6 < |\\eta| < 2.4 region of the muon endcaps with large-area triple-GEM detectors. Given their good spatial resolution, high rate capability, and radiation hardness, these micro-pattern gas detectors are an appealing option for simultaneously enhancing muon tracking and triggering capabilities in a future upgrade of the CMS detector. A general overview of this feasibility study will be presented. The design and construction of small (10\\times10 cm2) and full-size trapezoidal (1\\times0.5 m2) triple-GEM prototypes will be described. During detector assembly, different techniques for stretching the GEM foils were tested. Results from measurements with x-rays and from test beam campaigns at the CERN SPS will be shown for the small and large prototypes. Preliminary simulation studies on the expected...

  3. CMS GEM detector material study for the HL-LHC

    CERN Document Server

    Muhammad, Saleh

    2017-01-01

    A study on the Gaseous Electron Multiplier (GEM) foil material is performed to determine the moisture diffusion rate and saturation level and the moisture effects on its mechanical properties. The study is focused on the foil contact with ambient air and moisture to determine the value of the diffusion coefficient of water in the detector polyimide. The presence of water inside the detector foil can determine the changes in its mechanical and electrical properties. A simulated model is developed by taking into account the real GEM foil (hole dimensions, shapes and material), which describes the adsorption on a sample. This work describes the model, its experimental verification, the water diffusion within the entire sheet geometry of the GEM foil, thus gaining concentration profiles and the time required to saturate the system and the effects on the mechanical properties.

  4. Predicting nitrate discharge dynamics in mesoscale catchments using the lumped StreamGEM model and Bayesian parameter inference

    Science.gov (United States)

    Woodward, Simon James Roy; Wöhling, Thomas; Rode, Michael; Stenger, Roland

    2017-09-01

    The common practice of infrequent (e.g., monthly) stream water quality sampling for state of the environment monitoring may, when combined with high resolution stream flow data, provide sufficient information to accurately characterise the dominant nutrient transfer pathways and predict annual catchment yields. In the proposed approach, we use the spatially lumped catchment model StreamGEM to predict daily stream flow and nitrate concentration (mg L-1 NO3-N) in four contrasting mesoscale headwater catchments based on four years of daily rainfall, potential evapotranspiration, and stream flow measurements, and monthly or daily nitrate concentrations. Posterior model parameter distributions were estimated using the Markov Chain Monte Carlo sampling code DREAMZS and a log-likelihood function assuming heteroscedastic, t-distributed residuals. Despite high uncertainty in some model parameters, the flow and nitrate calibration data was well reproduced across all catchments (Nash-Sutcliffe efficiency against Log transformed data, NSL, in the range 0.62-0.83 for daily flow and 0.17-0.88 for nitrate concentration). The slight increase in the size of the residuals for a separate validation period was considered acceptable (NSL in the range 0.60-0.89 for daily flow and 0.10-0.74 for nitrate concentration, excluding one data set with limited validation data). Proportions of flow and nitrate discharge attributed to near-surface, fast seasonal groundwater and slow deeper groundwater were consistent with expectations based on catchment geology. The results for the Weida Stream in Thuringia, Germany, using monthly as opposed to daily nitrate data were, for all intents and purposes, identical, suggesting that four years of monthly nitrate sampling provides sufficient information for calibration of the StreamGEM model and prediction of catchment dynamics. This study highlights the remarkable effectiveness of process based, spatially lumped modelling with commonly available monthly

  5. GEM Detector Performance Assessment in the BM@N Experiment

    Science.gov (United States)

    Kapishin, Mikhail; Karjavin, Vladimir; Kulish, Elena; Lenivenko, Vasilisa; Makankin, Alexander; Maksymchuk, Anna; Palichik, Vladimir; Vasiliev, Sergey

    2018-02-01

    The Gas Electron Multiplier (GEM) chambers are developed for modern purposes in the elementary particle physics. In the BM@N experiment, a GEM system is used for the reconstruction of the trajectories of the charged particles. The investigation of GEM performance (efficiency and spatial resolution) is presented.

  6. GEM Detector Performance Assessment in the BM@N Experiment

    Directory of Open Access Journals (Sweden)

    Kapishin Mikhail

    2018-01-01

    Full Text Available The Gas Electron Multiplier (GEM chambers are developed for modern purposes in the elementary particle physics. In the BM@N experiment, a GEM system is used for the reconstruction of the trajectories of the charged particles. The investigation of GEM performance (efficiency and spatial resolution is presented.

  7. Ohio 4-H Agents' Perceptions of the Level of Importance and Frequency of Use of the Eighteen Components of the GEMS Model of Volunteer Administration.

    Science.gov (United States)

    Deppe, Catherine A.; Culp, Ken, III

    2001-01-01

    4-H youth development agents (n=81) identified the importance and frequency of use of the phases in the GEMS (Generate, Educate, Motivate, Sustain) model of volunteer administration. The greatest discrepancy between importance and frequency was in sustaining volunteer involvement. Areas for agents' professional development were identified.…

  8. Conceptual design and development of GEM based detecting system for tomographic tungsten focused transport monitoring

    Science.gov (United States)

    Chernyshova, M.; Czarski, T.; Malinowski, K.; Kowalska-Strzęciwilk, E.; Poźniak, K.; Kasprowicz, G.; Zabołotny, W.; Wojeński, A.; Kolasiński, P.; Mazon, D.; Malard, P.

    2015-10-01

    Implementing tungsten as a plasma facing material in ITER and future fusion reactors will require effective monitoring of not just its level in the plasma but also its distribution. That can be successfully achieved using detectors based on Gas Electron Multiplier (GEM) technology. This work presents the conceptual design of the detecting unit for poloidal tomography to be tested at the WEST project tokamak. The current stage of the development is discussed covering aspects which include detector's spatial dimensions, gas mixtures, window materials and arrangements inside and outside the tokamak ports, details of detector's structure itself and details of the detecting module electronics. It is expected that the detecting unit under development, when implemented, will add to the safe operation of tokamak bringing the creation of sustainable nuclear fusion reactors a step closer. A shorter version of this contribution is due to be published in PoS at: 1st EPS conference on Plasma Diagnostics

  9. A free-volume modification of GEM-QC to correlate VLE and LLE in polymer solutions

    International Nuclear Information System (INIS)

    Radfarnia, H.R.; Taghikhani, V.; Ghotbi, C.; Khoshkbarchi, M.K.

    2004-01-01

    The generalized quasi-chemical (GEM-QC) model proposed by Wang and Vera is modified to correlate better the phase equilibrium and to overcome the shortcoming of the original model to predict the lower critical solution temperature (LCST) of binary polymer solutions. This shortcoming is mainly because the GEM-QC model does not consider the effect of free-volume, which is important in systems containing molecules with large size differences. The proposed modification is based on replacing the combinatorial term of the GEM-QC model by a term proposed by Kontogerogis et al., which includes the effect of the free-volume. The main advantage of the free volume generalized quasi-chemical (GEM-QC-FV) model over the original GEM-QC is its ability to predict the phase behaviour of binary polymer solutions with LCST behaviour. In addition, the free volume UNIQUAC (UNIQUAC-FV) model is used to correlate VLE and LLE experimental data for binary polymer solutions. The comparison of the results obtained from the GEM-QC-FV model and the UNIQUAC-FV model shows the superiority of the GEM-QC-FV model in correlating the VLE and LLE experimental data for binary polymer solutions

  10. A micro-TCA based data acquisition system for the Triple-GEM detectors for the upgrade of the CMS forward muon spectrometer

    Science.gov (United States)

    Lenzi, T.

    2017-01-01

    The Gas Electron Multiplier (GEM) upgrade project aims at improving the performance of the muon spectrometer of the Compact Muon Solenoid (CMS) experiment which will suffer from the increase in luminosity of the Large Hadron Collider (LHC). The GEM collaboration proposes to instrument the first muon station with Triple-GEM detectors, a technology which has proven to be resistant to high fluxes of particles. The architecture of the readout system is based on the use of the microTCA standard hosting FPGA-based Advanced Mezzanine Card (AMC) and of the Versatile Link with the GBT chipset to link the on-detector electronics to the micro-TCA boards. For the front-end electronics a new ASIC, called VFAT3, is being developed. On the detector, a Xilinx Virtex-6 FPGA mezzanine board, called the OptoHybrid, has to collect the data from 24 VFAT3s and to transmit the data optically to the off-detector micro-TCA electronics, as well as to transmit the trigger data at 40 MHz to the CMS Cathode Strip Chamber (CSC) trigger. The microTCA electronics provides the interfaces from the detector (and front-end electronics) to the CMS DAQ, TTC (Timing, Trigger and Control) and Trigger systems. In this paper, we will describe the DAQ system of the Triple-GEM project and provide results from the latest test beam campaigns done at CERN.

  11. Robustness test of a system of MSGC+GEM detectors at the cyclotron facility of the Paul Scherrer institute

    Energy Technology Data Exchange (ETDEWEB)

    Ageron, M.; Albert, A.; Barvich, T.; Beaumont, W.; Beckers, T.; Bernier, K.; Bluem, P.; Bouhali, O.; Boulogne, I.; Bouvet, D.; Brom, J.M.; Charles, F.; Coffin, J.; Contardo, D.; Daubie, E.; Didierjean, F.; Erdmann, M.; De Lentdecker, G.; Devroede, O.; De Troy, J.; Ernenwein, J.P.; Fahrer, M.; Fluegge, G.; Fontaine, J.C.; Geist, W.; Goerlach, U.; Gottschalk, M.; Helleboid, J.M.; Huss, D.; Iacopi, F.; Kaercher, K.; Kuehn, F.; Juillot, P. E-mail: juillot@in2p3.fr; Lounis, A.; Maazouzi, C.; Macke, D.; Martin, C.; Mirabito, L.; Moreau, S.; Mueller, T.; Neuberger, D.; Nowack, A.; Perries, S.; Ripp-Baudot, I.; Roederer, F.; Schulte, R.; Shekhtman, L.; Simonis, H.J.; Struczinski, W.; Tatarinov, A.; Thuemmel, W.H.; Udo, F.; Doninck, W. van; Dyck, C. van; Vander Velde, C.; Vanlaer, P.; Lancker, L. van; Weiler, T.; Zander, A.; Zghiche, A.; Zhukov, V

    2001-10-01

    A system of detector modules consisting of a large size Gas Electron Multiplier (GEM), coupled to Micro Strip Gas Counters (MSGC), has been exposed to a pion beam at the Paul Scherrer Institute Cyclotron facility. As part of a CMS tracker milestone, the aim of this test was to investigate the robustness of such detectors when exposed to experimental conditions close to what is expected at the Large Hadron Collider (LHC) of CERN. Eighteen detector modules have been operated at voltage settings corresponding to 98% detection efficiency for Minimum Ionizing Particles during a period of 5 weeks. Sparking rates and strip losses have been monitored throughout the exposure. An operation margin of at least a factor of three with respect to the required gas gain has been demonstrated.

  12. Not Your Ordinary GEM

    Science.gov (United States)

    2001-01-01

    Through Small Business Innovation Research (SBIR) funding from NASA's Stennis Space Center, Geophex devised a new design for broadband electromagnetic sensors. Geophex developed a patented sensing technology, capable not only of coastal monitoring, but also a variety of other functions, including environmental pollution characterization, groundwater contamination detection, archaeological study, and mineral detection. The new technology is offered in several of the company's products the GEM-2, GEM-2A, and the GEM-3. The Geophex products consist of two primary electromagnetic coils, which are stimulated by alternating currents that generate a magnetic field in the object targeted for investigation. GEM-2 is a handheld, lightweight, programmable, digital device. GEM-2A is an airborne version of the sensor. Suspended from a helicopter, the GEM-2A is used to search for mineral deposits and to survey large tracts of land. The GEM-3 is capable of detecting buried landmines and other active munitions. GEM-3 identifies landmines by their brand names. Because each landmine has its own unique electromagnetic response to the broad frequency band emitted by the GEM-3, bomb identification and disposal strategies are made easier.

  13. Impact of melt ponds on Arctic sea ice in the HadGEM3 global coupled climate model

    Science.gov (United States)

    Schroeder, David; Rae, Jamie; Feltham, Daniel; Flocco, Daniela; Tsamados, Michel; Ridley, Jeff; Keen, Ann

    2015-04-01

    Stand-alone sea ice simulations with a physical based melt pond model reveal a strong correlation between the simulated spring pond fraction and the observed as well as simulated September sea ice extent for the period 1979 to 2014. This is explained by a positive feedback mechanism: more ponds reduce the albedo; a lower albedo causes more melting; more melting increases pond fraction. This feedback process is a potential reason for the acceleration of Arctic sea ice decrease in the last decade and the failure of many climate models (without an implicit pond model) to simulate the observed decrease. We implemented the Los Alamos sea ice model CICE 5 including our physical based melt pond model into the latest version of the Hadley Centre coupled climate model, HadGEM3. The model surface shortwave radiation scheme has been adjusted to account for pond fraction and depth. A 30-year simulation with constant present-day atmospheric C02 has been undertaken. The sensitivity of the simulated sea ice area and volume to parameters pertinent to the melt pond parameterization will be discussed and compared to those in uncoupled (forced) simulations. The analysis focuses on the impact of melt ponds on the summer melt, and asks if the strong correlation between spring pond fraction and September sea ice extent found in stand-alone simulations, can be confirmed in the coupled climate simulation.

  14. Evaluation of biomass burning aerosols in the HadGEM3 climate model with observations from the SAMBBA field campaign

    Directory of Open Access Journals (Sweden)

    B. T. Johnson

    2016-11-01

    Full Text Available We present observations of biomass burning aerosol from the South American Biomass Burning Analysis (SAMBBA and other measurement campaigns, and use these to evaluate the representation of biomass burning aerosol properties and processes in a state-of-the-art climate model. The evaluation includes detailed comparisons with aircraft and ground data, along with remote sensing observations from MODIS and AERONET. We demonstrate several improvements to aerosol properties following the implementation of the Global Model for Aerosol Processes (GLOMAP-mode modal aerosol scheme in the HadGEM3 climate model. This predicts the particle size distribution, composition, and optical properties, giving increased accuracy in the representation of aerosol properties and physical–chemical processes over the Coupled Large-scale Aerosol Scheme for Simulations in Climate Models (CLASSIC bulk aerosol scheme previously used in HadGEM2. Although both models give similar regional distributions of carbonaceous aerosol mass and aerosol optical depth (AOD, GLOMAP-mode is better able to capture the observed size distribution, single scattering albedo, and Ångström exponent across different tropical biomass burning source regions. Both aerosol schemes overestimate the uptake of water compared to recent observations, CLASSIC more so than GLOMAP-mode, leading to a likely overestimation of aerosol scattering, AOD, and single scattering albedo at high relative humidity. Observed aerosol vertical distributions were well captured when biomass burning aerosol emissions were injected uniformly from the surface to 3 km. Finally, good agreement between observed and modelled AOD was gained only after scaling up GFED3 emissions by a factor of 1.6 for CLASSIC and 2.0 for GLOMAP-mode. We attribute this difference in scaling factor mainly to different assumptions for the water uptake and growth of aerosol mass during ageing via oxidation and condensation of organics. We also note

  15. Data Integration for Spatio-Temporal Patterns of Gene Expression of Zebrafish development: the GEMS database

    Directory of Open Access Journals (Sweden)

    Belmamoune Mounia

    2008-06-01

    Full Text Available The Gene Expression Management System (GEMS is a database system for patterns of gene expression. These patterns result from systematic whole-mount fluorescent in situ hybridization studies on zebrafish embryos. GEMS is an integrative platform that addresses one of the important challenges of developmental biology: how to integrate genetic data that underpin morphological changes during embryogenesis. Our motivation to build this system was by the need to be able to organize and compare multiple patterns of gene expression at tissue level. Integration with other developmental and biomolecular databases will further support our understanding of development. The GEMS operates in concert with a database containing a digital atlas of zebrafish embryo; this digital atlas of zebrafish development has been conceived prior to the expansion of the GEMS. The atlas contains 3D volume models of canonical stages of zebrafish development in which in each volume model element is annotated with an anatomical term. These terms are extracted from a formal anatomical ontology, i.e. the Developmental Anatomy Ontology of Zebrafish (DAOZ. In the GEMS, anatomical terms from this ontology together with terms from the Gene Ontology (GO are also used to annotate patterns of gene expression and in this manner providing mechanisms for integration and retrieval . The annotations are the glue for integration of patterns of gene expression in GEMS as well as in other biomolecular databases. At the one hand, zebrafish anatomy terminology allows gene expression data within GEMS to be integrated with phenotypical data in the 3D atlas of zebrafish development. At the other hand, GO terms extend GEMS expression patterns integration to a wide range of bioinformatics resources.

  16. GEM: Performance and aging tests

    International Nuclear Information System (INIS)

    Cho, H.S.; Kadyk, J.; Han, S.H.; Hong, W.S.; Perez-Mendez, V.; Wenzel, W.; Pitts, K.; Martin, M.D.; Hutchins, J.B.

    1999-01-01

    Performance and aging tests have been done to characterize Gas Electron Multipliers (GEMs), including further design improvements such as a thicker GEM and a closed GEM. Since the effective GEM gain is typically smaller than the absolute GEM gain, due to trapping of avalanche electrons at the bottom GEM electrode, the authors performed field simulations and measurements for better understanding, and discuss methods to eliminate this effect. Other performance parameters of the GEMs are also presented, including absolute GEM gain, short-term and long-term gain stabilities

  17. Operation of the triple-GEM detectors in the tagging system of the KEDR experiment on the VEPP-4M collider

    Energy Technology Data Exchange (ETDEWEB)

    Aulchenko, V M; Beloborodova, O L; Bobrov, A V; Bondar, A E; Kudryavtsev, V N; Shamov, A G; Shekhtman, L I; Zhilich, V N; Zhulanov, V V, E-mail: L.I.Shekhtman@inp.nsk.su [Budker Institute of Nuclear Physics, 11 Lavrentiev Avenue, Novosibirsk 630090 (Russian Federation)

    2011-07-15

    The tagging system (TS) of the KEDR detector is designed for study of two-photon interactions on the VEPP-4M electron-positron collider. The upgrade of the TS was completed and 8 triple-GEM detectors were added to the system with a single detector sensitive area up to 250*100 mm{sup 2}, a spatial resolution in the beam orbit plane close to 70 {mu}m and a small angle stereo readout providing a resolution of around 200 {mu}m in perpendicular direction. The triple-GEM detectors were included into the KEDR DAQ system, and since the beginning of the 2010-2011 season they have demonstrated stable operation at a gas gain of 20000-40000 and efficiency of 95-97%. The new detectors will allow performing background suppression and improving the energy resolution of the system.

  18. Development of the data acquisition system for the Triple-GEM detectors for the upgrade of the CMS forward muon spectrometer

    CERN Document Server

    Abbaneo, D; Akl, M A; Ahmed, W; Armaingaud, C; Aspell, P; Assran, Y; Bally, S; Ban, Y; Banerjee, S; Barria, P; Benussi, L; Bhopatkar, V; Bianco, S; Bos, J; Bouhali, O; Cai, J; Calabria, C; Castaneda, A; Cauwenbergh, S; Celik, A; Christiansen, J; Colafranceschi, S; Colaleo, A; Conde Garcia, A; Dabrowski, M; De Lentdecker, G; De Oliveira, R; De Robertis, G; Dildick, S; Ferry, S; Flanagan, W; Gilmore, J; Guilloux, F; Gutierrez, A; Hoepfner, K; Hohlmann, M; Kamon, T; Karchin, P E; Khotilovich, V; Korntheuer, M; Krutelyov, S; Lenzi, T; Loddo, F; Maerschalk, T; Magazzu, G; Maggi, M; Maghrbi, Y; Marchioro, A; Marinov, A; Mazumdar, N; Merlin, J A; Mukhopadhyay, S; Nuzzo, S; Oliveri, E; Philipps, B; Piccolo, D; Postema, H; Radi, A; Radogna, R; Raffone, G; Ranieri, A; Rodrigues, A; Ropelewski, L; Safonov, A; Sakharov, A; Salva, S; Saviano, G; Sharma, A; Talvitie, J; Tatarinov, A; Teng, H; Turini, N; Tuuva, T; Twigger, J; Tytgat, M; van Stenis, M.; Verhagen, E; Yang, Y; Zaganidis, N; Zenoni, F

    2014-01-01

    In this contribution we will report on the progress of thedesign of the readout and data acquisition system being developedfor triple-GEM detectors which will be installed in the forwardregion (1.5 < |η| < 2.2) of the CMS muonspectrometer during the 2nd long shutdown of the LHC, expectedin the period 2017–2018. The system will be designed to take fulladvantage of current generic developments introduced for the LHCupgrades. The current design is based on the use of CERN GLIB boardshosted in micro-TCA crates for the off-detector electronics and theVersatile Link with the GBT chipset to link the front-endelectronics to the GLIB boards. In this contribution we willdescribe the physics goals, the hardware architectures and report onthe expected performance of the CMS GEM readout system, includingpreliminary timing resolution simulations.

  19. A micro-TCA based data acquisition system for the Triple-GEM detectors for the upgrade of the CMS forward muon spectrometer

    CERN Document Server

    Lenzi, Thomas

    2016-01-01

    We will present the electronic and DAQ system being developed for TripleGEM detectors which will be installed in the CMS muon spectrometer. The microTCA system uses an Advanced Mezzanine Card equipped with an FPGA and the Versatile Link with the GBT chipset to link the front and back-end. On the detector an FPGA mezzanine board, the OptoHybrid, has to collect the data from the detector readout chips to transmit them optically to the microTCA boards using the GBT protocol. We will describe the hardware architecture, report on the status of the developments, and present results obtained with the system.In this contribution we will report on the progress of the design of the electronic readout and data acquisition (DAQ) system being developed for Triple-GEM detectors which will be installed in the forward region (1.5 < eta < 2.2) of the CMS muon spectrometer during the 2nd long shutdown of the LHC, planed for the period 2018-2019. The architecture of the Triple-GEM readout system is based on the use of the...

  20. Meeting the Challenge of Earthquake Risk Globalisation: Towards the Global Earthquake Model GEM (Sergey Soloviev Medal Lecture)

    Science.gov (United States)

    Zschau, J.

    2009-04-01

    Earthquake risk, like natural risks in general, has become a highly dynamic and globally interdependent phenomenon. Due to the "urban explosion" in the Third World, an increasingly complex cross linking of critical infrastructure and lifelines in the industrial nations and a growing globalisation of the world's economies, we are presently facing a dramatic increase of our society's vulnerability to earthquakes in practically all seismic regions on our globe. Such fast and global changes cannot be captured with conventional earthquake risk models anymore. The sciences in this field are, therefore, asked to come up with new solutions that are no longer exclusively aiming at the best possible quantification of the present risks but also keep an eye on their changes with time and allow to project these into the future. This does not apply to the vulnerablity component of earthquake risk alone, but also to its hazard component which has been realized to be time-dependent, too. The challenges of earthquake risk dynamics and -globalisation have recently been accepted by the Global Science Forum of the Organisation for Economic Co-operation and Development (OECD - GSF) who initiated the "Global Earthquake Model (GEM)", a public-private partnership for establishing an independent standard to calculate, monitor and communicate earthquake risk globally, raise awareness and promote mitigation.

  1. A hydrological prediction system based on the SVS land-surface scheme: efficient calibration of GEM-Hydro for streamflow simulation over the Lake Ontario basin

    Directory of Open Access Journals (Sweden)

    É. Gaborit

    2017-09-01

    Full Text Available This work explores the potential of the distributed GEM-Hydro runoff modeling platform, developed at Environment and Climate Change Canada (ECCC over the last decade. More precisely, the aim is to develop a robust implementation methodology to perform reliable streamflow simulations with a distributed model over large and partly ungauged basins, in an efficient manner. The latest version of GEM-Hydro combines the SVS (Soil, Vegetation and Snow land-surface scheme and the WATROUTE routing scheme. SVS has never been evaluated from a hydrological point of view, which is done here for all major rivers flowing into Lake Ontario. Two established hydrological models are confronted to GEM-Hydro, namely MESH and WATFLOOD, which share the same routing scheme (WATROUTE but rely on different land-surface schemes. All models are calibrated using the same meteorological forcings, objective function, calibration algorithm, and basin delineation. GEM-Hydro is shown to be competitive with MESH and WATFLOOD: the NSE  √  (Nash–Sutcliffe criterion computed on the square root of the flows is for example equal to 0.83 for MESH and GEM-Hydro in validation on the Moira River basin, and to 0.68 for WATFLOOD. A computationally efficient strategy is proposed to calibrate SVS: a simple unit hydrograph is used for routing instead of WATROUTE. Global and local calibration strategies are compared in order to estimate runoff for ungauged portions of the Lake Ontario basin. Overall, streamflow predictions obtained using a global calibration strategy, in which a single parameter set is identified for the whole basin of Lake Ontario, show accuracy comparable to the predictions based on local calibration: the average NSE  √  in validation and over seven subbasins is 0.73 and 0.61, respectively for local and global calibrations. Hence, global calibration provides spatially consistent parameter values, robust performance at gauged locations, and reduces the

  2. A hydrological prediction system based on the SVS land-surface scheme: efficient calibration of GEM-Hydro for streamflow simulation over the Lake Ontario basin

    Science.gov (United States)

    Gaborit, Étienne; Fortin, Vincent; Xu, Xiaoyong; Seglenieks, Frank; Tolson, Bryan; Fry, Lauren M.; Hunter, Tim; Anctil, François; Gronewold, Andrew D.

    2017-09-01

    This work explores the potential of the distributed GEM-Hydro runoff modeling platform, developed at Environment and Climate Change Canada (ECCC) over the last decade. More precisely, the aim is to develop a robust implementation methodology to perform reliable streamflow simulations with a distributed model over large and partly ungauged basins, in an efficient manner. The latest version of GEM-Hydro combines the SVS (Soil, Vegetation and Snow) land-surface scheme and the WATROUTE routing scheme. SVS has never been evaluated from a hydrological point of view, which is done here for all major rivers flowing into Lake Ontario. Two established hydrological models are confronted to GEM-Hydro, namely MESH and WATFLOOD, which share the same routing scheme (WATROUTE) but rely on different land-surface schemes. All models are calibrated using the same meteorological forcings, objective function, calibration algorithm, and basin delineation. GEM-Hydro is shown to be competitive with MESH and WATFLOOD: the NSE √ (Nash-Sutcliffe criterion computed on the square root of the flows) is for example equal to 0.83 for MESH and GEM-Hydro in validation on the Moira River basin, and to 0.68 for WATFLOOD. A computationally efficient strategy is proposed to calibrate SVS: a simple unit hydrograph is used for routing instead of WATROUTE. Global and local calibration strategies are compared in order to estimate runoff for ungauged portions of the Lake Ontario basin. Overall, streamflow predictions obtained using a global calibration strategy, in which a single parameter set is identified for the whole basin of Lake Ontario, show accuracy comparable to the predictions based on local calibration: the average NSE √ in validation and over seven subbasins is 0.73 and 0.61, respectively for local and global calibrations. Hence, global calibration provides spatially consistent parameter values, robust performance at gauged locations, and reduces the complexity and computation burden of the

  3. Downscaling of the global HadGEM2-ES results to model the future and present-day ocean conditions of the southeastern Brazilian continental shelf

    Science.gov (United States)

    Toste, Raquel; Assad, Luiz Paulo de Freitas; Landau, Luiz

    2017-09-01

    Changes in the regional hydrodynamics of the region of the South Atlantic near the east coast of Brazil were evaluated from the beginning to the end of the century. The analysis was based on the anomalies from two downscaling experiments using the HadGEM2-ES outputs for the historical and RCP4.5 runs from the Coupled Model Inter-comparison Project phase 5. The anomalies between the experiments were collected in a system of two nested grids, with 1/3° and 1/12° horizontal resolutions. A northward displacement of the Brazil Current (BC), a southward BC transport intensification, and a 1.44 ° C increase of the mean values of sea surface temperatures were observed. The sea level rise (SLR) was projected up until 2100 across the study area, and the spatial variations were shown to have an average on SLR rate of 7.30 mm year^{-1} for those regions close to the coast. These results highlight the importance of studying climate change and applying methods to enable the evaluation of its effects on coastal zones, especially for regions with few existing studies, such as the Brazilian continental shelf area.

  4. Design and Construction of a First Prototype Muon Tomography System with GEM Detectors for the Detection of Nuclear Contraband

    CERN Document Server

    AUTHOR|(CDS)2074269; Grasso, L; Locke, J B; Quintero, A; Mitra, D

    2009-01-01

    Current radiation portal monitors at sea ports and international borders that employ standard radiation detection techniques are not very sensitive to nuclear contraband that is well shielded to absorb emanating radiation. Muon Tomography (MT) based on the measurement of multiple scattering of atmospheric cosmic ray muons traversing cargo or vehicles that contain high-Z material is a promising passive interrogation technique for solving this problem. We report on the design and construction of compact Micro-Pattern Gas Detectors for a small prototype MT station. This station will employ 10 tracking stations based on 30cm x 30cm low-mass triple-GEM detectors with 2D readout. Due to the excellent spatial resolution of GEMs it is sufficient to use a gap of only a few cm between tracking stations. Together with the compact size of the GEM detectors this allows the GEM MT station to be an order of magnitude more compact than MT stations using traditional drift tubes. We present details of the production and assemb...

  5. GEM-CEDAR Challenge: Poynting Flux at DMSP and Modeled Joule Heat

    Science.gov (United States)

    Rastaetter, Lutz; Shim, Ja Soon; Kuznetsova, Maria M.; Kilcommons, Liam M.; Knipp, Delores J.; Codrescu, Mihail; Fuller-Rowell, Tim; Emery, Barbara; Weimer, Daniel R.; Cosgrove, Russell; hide

    2016-01-01

    Poynting flux into the ionosphere measures the electromagnetic energy coming from the magnetosphere. This energy flux can vary greatly between quiet times and geomagnetic active times. As part of the Geospace Environment Modeling-coupling energetics and dynamics of atmospheric regions modeling challenge, physics-based models of the 3-D ionosphere and ionospheric electrodynamics solvers of magnetosphere models that specify Joule heat and empirical models specifying Poynting flux were run for six geomagnetic storm events of varying intensity. We compared model results with Poynting flux values along the DMSP-15 satellite track computed from ion drift meter and magnetic field observations. Although being a different quantity, Joule heat can in practice be correlated to incoming Poynting flux because the energy is dissipated primarily in high latitudes where Poynting flux is being deposited. Within the physics-based model group, we find mixed results with some models overestimating Joule heat and some models agreeing better with observed Poynting flux rates as integrated over auroral passes. In contrast, empirical models tend to underestimate integrated Poynting flux values. Modeled Joule heat or Poynting flux patterns often resemble the observed Poynting flux patterns on a large scale, but amplitudes can differ by a factor of 2 or larger due to the highly localized nature of observed Poynting flux deposition that is not captured by the models. In addition, the positioning of modeled patterns appear to be randomly shifted against the observed Poynting flux energy input. This study is the first to compare Poynting flux and Joule heat in a large variety of models of the ionosphere.

  6. GEM-CEDAR challenge: Poynting flux at DMSP and modeled Joule heat

    Science.gov (United States)

    Rastätter, Lutz; Shim, Ja Soon; Kuznetsova, Maria M.; Kilcommons, Liam M.; Knipp, Delores J.; Codrescu, Mihail; Fuller-Rowell, Tim; Emery, Barbara; Weimer, Daniel R.; Cosgrove, Russell; Wiltberger, Michael; Raeder, Joachim; Li, Wenhui; Tóth, Gábor; Welling, Daniel

    2016-02-01

    Poynting flux into the ionosphere measures the electromagnetic energy coming from the magnetosphere. This energy flux can vary greatly between quiet times and geomagnetic active times. As part of the Geospace Environment Modeling-coupling energetics and dynamics of atmospheric regions modeling challenge, physics-based models of the 3-D ionosphere and ionospheric electrodynamics solvers of magnetosphere models that specify Joule heat and empirical models specifying Poynting flux were run for six geomagnetic storm events of varying intensity. We compared model results with Poynting flux values along the DMSP-15 satellite track computed from ion drift meter and magnetic field observations. Although being a different quantity, Joule heat can in practice be correlated to incoming Poynting flux because the energy is dissipated primarily in high latitudes where Poynting flux is being deposited. Within the physics-based model group, we find mixed results with some models overestimating Joule heat and some models agreeing better with observed Poynting flux rates as integrated over auroral passes. In contrast, empirical models tend to underestimate integrated Poynting flux values. Modeled Joule heat or Poynting flux patterns often resemble the observed Poynting flux patterns on a large scale, but amplitudes can differ by a factor of 2 or larger due to the highly localized nature of observed Poynting flux deposition that is not captured by the models. In addition, the positioning of modeled patterns appear to be randomly shifted against the observed Poynting flux energy input. This study is the first to compare Poynting flux and Joule heat in a large variety of models of the ionosphere.

  7. Top-down/bottom-up description of electricity sector for Switzerland using the GEM-E3 computable general equilibrium model

    Energy Technology Data Exchange (ETDEWEB)

    Krakowski, R. A

    2006-06-15

    Participation of the Paul Scherrer Institute (PSI) in the advancement and extension of the multi-region, Computable General Equilibrium (CGE) model GEM-E3 (CES/KUL, 2002) focused primarily on two top-level facets: a) extension of the model database and model calibration, particularly as related to the second component of this study, which is; b) advancement of the dynamics of innovation and investment, primarily through the incorporation of Exogenous Technical Learning (ETL) into he Bottom-Up (BU, technology-based) part of the dynamic upgrade; this latter activity also included the completion of the dynamic coupling of the BU description of the electricity sector with the 'Top-Down' (TD, econometric) description of the economy inherent to the GEM-E3 CGE model. The results of this two- component study are described in two parts that have been combined in this single summary report: Part I describes the methodology and gives illustrative results from the BUTD integration, as well as describing the approach to and giving preliminary results from incorporating an ETL description into the BU component of the overall model; Part II reports on the calibration component of task in terms of: a) formulating a BU technology database for Switzerland based on previous work; incorporation of that database into the GEM-E3 model; and calibrating the BU database with the TD database embodied in the (Swiss) Social Accounting Matrix (SAM). The BUTD coupling along with the ETL incorporation described in Part I represent the major effort embodied in this investigation, but this effort could not be completed without the calibration preamble reported herein as Part II. A brief summary of the scope of each of these key study components is given. (author)

  8. Top-down/bottom-up description of electricity sector for Switzerland using the GEM-E3 computable general equilibrium model

    International Nuclear Information System (INIS)

    Krakowski, R. A.

    2006-06-01

    Participation of the Paul Scherrer Institute (PSI) in the advancement and extension of the multi-region, Computable General Equilibrium (CGE) model GEM-E3 (CES/KUL, 2002) focused primarily on two top-level facets: a) extension of the model database and model calibration, particularly as related to the second component of this study, which is; b) advancement of the dynamics of innovation and investment, primarily through the incorporation of Exogenous Technical Learning (ETL) into he Bottom-Up (BU, technology-based) part of the dynamic upgrade; this latter activity also included the completion of the dynamic coupling of the BU description of the electricity sector with the 'Top-Down' (TD, econometric) description of the economy inherent to the GEM-E3 CGE model. The results of this two- component study are described in two parts that have been combined in this single summary report: Part I describes the methodology and gives illustrative results from the BUTD integration, as well as describing the approach to and giving preliminary results from incorporating an ETL description into the BU component of the overall model; Part II reports on the calibration component of task in terms of: a) formulating a BU technology database for Switzerland based on previous work; incorporation of that database into the GEM-E3 model; and calibrating the BU database with the TD database embodied in the (Swiss) Social Accounting Matrix (SAM). The BUTD coupling along with the ETL incorporation described in Part I represent the major effort embodied in this investigation, but this effort could not be completed without the calibration preamble reported herein as Part II. A brief summary of the scope of each of these key study components is given. (author)

  9. USING GEM - GLOBAL ECONOMIC MODEL IN ACHIEVING A GLOBAL ECONOMIC FORECAST

    Directory of Open Access Journals (Sweden)

    Camelia Madalina Orac

    2013-12-01

    Full Text Available The global economic development model has proved to be insufficiently reliable under the new economic crisis. As a result, the entire theoretical construction about the global economy needs rethinking and reorientation. In this context, it is quite clear that only through effective use of specific techniques and tools of economic-mathematical modeling, statistics, regional analysis and economic forecasting it is possible to obtain an overview of the future economy.

  10. Development of a glass GEM

    International Nuclear Information System (INIS)

    Takahashi, Hiroyuki; Mitsuya, Yuki; Fujiwara, Takeshi; Fushie, Takashi

    2013-01-01

    Gas electron multipliers (GEMs) apply the concept of gas amplification inside many tiny holes, realizing robust and high-gain proportional counters. However, the polyimide substrate of GEMs prevents them from being used in sealed detector applications. We have fabricated and tested glass GEMs (G-GEMs) with substrates made of photosensitive glass material from the Hoya Corporation. We fabricated G-GEMs with several different hole diameters and thicknesses and successfully operated test G-GEMs with a 100×100 mm 2 effective area. The uniformity of our G-GEMs was good, and the energy resolution for 5.9 keV X-rays was 18.8% under uniform irradiation of the entire effective area. A gas gain by the G-GEMs of up to 6700 was confirmed with a gas mixture of Ar (70%)+CH 4 (30%). X-ray imaging using the charge division readout method was demonstrated

  11. GEM simulation methods development

    International Nuclear Information System (INIS)

    Tikhonov, V.; Veenhof, R.

    2002-01-01

    A review of methods used in the simulation of processes in gas electron multipliers (GEMs) and in the accurate calculation of detector characteristics is presented. Such detector characteristics as effective gas gain, transparency, charge collection and losses have been calculated and optimized for a number of GEM geometries and compared with experiment. A method and a new special program for calculations of detector macro-characteristics such as signal response in a real detector readout structure, and spatial and time resolution of detectors have been developed and used for detector optimization. A detailed development of signal induction on readout electrodes and electronics characteristics are included in the new program. A method for the simulation of charging-up effects in GEM detectors is described. All methods show good agreement with experiment

  12. The role of evaporites in the formation of gems during metamorphism of carbonate platforms: a review

    Science.gov (United States)

    Giuliani, Gaston; Dubessy, Jean; Ohnenstetter, Daniel; Banks, David; Branquet, Yannick; Feneyrol, Julien; Fallick, Anthony E.; Martelat, Jean-Emmanuel

    2018-01-01

    The mineral and fluid inclusions trapped by gemstones during the metamorphism of carbonate platform successions are precious markers for the understanding of gem genesis. The nature and chemical composition of inclusions highlight the major contribution of evaporites through dissolution or fusion, depending on the temperature of formation from greenschist to granulite facies. The fluids are highly saline NaCl-brines circulating either in an open system in the greenschist facies (Colombian and Afghan emeralds) and with huge fluid-rock metasomatic interactions, or sulphurous fluids (ruby, garnet tsavorite, zoisite tanzanite and lapis-lazuli) or molten salts formed in a closed system with a low fluid mobility (ruby in marble) in the conditions of the amphibolite to granulite facies. These chloride-fluoride-sulphate ± carbonate-rich fluids scavenged the metals essential for gem formation. At high temperature, the anions SO4 2-, NO3 -, BO3 - and F- are powerful fluxes which lower the temperature of chloride- and fluoride-rich ionic liquids. They provided transport over a very short distance of aluminium and/or silica and transition metals which are necessary for gem growth. In summary, the genetic models proposed for these high-value and ornamental gems underline the importance of the metamorphism of evaporites formed on continental carbonate shelves and emphasise the chemical power accompanying metamorphism at moderate to high temperatures of evaporite-rich and organic matter-rich protoliths to form gem minerals.

  13. The Ozone Layer. UNEP/GEMS Environment Library No. 2.

    Science.gov (United States)

    United Nations Environment Programme, Nairobi (Kenya).

    Since the United Nations Environment Program (UNEP) was created, more than a dozen years ago, public understanding of the environmental issues confronting our planet has increased enormously. The Global Environment Monitoring System (GEMS) has provided several environmental assessments. The aim of the UNEP/GEMS Environment Library is to provide…

  14. Numerical Representation of Wintertime Near-Surface Inversions in the Arctic with a 2.5-km Version of the Global Environmental Multiscale (GEM) Model

    Science.gov (United States)

    Dehghan, A.; Mariani, Z.; Gascon, G.; Bélair, S.; Milbrandt, J.; Joe, P. I.; Crawford, R.; Melo, S.

    2017-12-01

    Environment and Climate Change Canada (ECCC) is implementing a 2.5-km resolution version of the Global Environmental Multiscale (GEM) model over the Canadian Arctic. Radiosonde observations were used to evaluate the numerical representation of surface-based temperature inversion which is a major feature in the Arctic region. Arctic surface-based inversions are often created by imbalance between radiative cooling processes at surface and warm air advection above. This can have a significant effect on vertical mixing of pollutants and moisture, and ultimately, on cloud formation. It is therefore important to correctly predict the existence of surface inversions along with their characteristics (i.e., intensity and depth). Previous climatological studies showed that the frequency and intensity of surface-based inversions are larger during colder months in the Arctic. Therefore, surface-based inversions were estimated using radiosonde measurements during winter (December 2015 to February 2016) at Iqaluit (Nunavut, Canada). Results show that the inversion intensity can exceed 10 K with depths as large as 1 km. Preliminary evaluation of GEM outputs reveals that the model tends to underestimate the intensity of near-surface inversions, and in some cases, the model failed to predict an inversion. This study presents the factors contributing to this bias including surface temperature and snow cover.

  15. Some Interesting Mathematical Gems

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 11; Issue 9. Some Interesting Mathematical Gems. V G Tikekar. General Article Volume 11 Issue 9 September 2006 pp 29-42 ... Author Affiliations. V G Tikekar1. c/o Thakar New Mahadwar Road Near Padmaraje School Kolhapur 416006, India.

  16. A Hidden GEM

    Science.gov (United States)

    Khan, Samia

    2012-01-01

    The internet abounds with free science education applications. But, on their own, these applications have limited capacity to teach students curricular concepts or skills. The author integrated several free web-based applications into a broader pedagogical approach called T-GEM, in which the teacher guides student investigations. In this article,…

  17. SUPERCOLLIDER: A GEM of a detector

    International Nuclear Information System (INIS)

    Anon.

    1993-01-01

    Now being prepared as a major experimental facility for the 87- kilometre Superconducting Supercollider (SSC) being built in Ellis County, Texas, is the GEM detector project. GEM thus becomes the companion to the Solenoidal Detector Collaboration (SDC), the first major SSC detector to emerge (March 1992, page 13). This is in keeping with the SSC Laboratory's aim of two major detectors with overlapping and complementary strengths. GEM is designed to observe all SSC signatures, with emphasis on precise measurement of electrons, photons and muons. Hence the name GEM - ''Gammas, Electrons and Muons.'' Design goals are clean signatures for leptons, jets, and missing transverse energy, maximum sensitivity to narrow resonances, and low backgrounds. Also important is maintaining significant capability at high luminosity (10 34 cm -2 s -1 ). GEM has some distinctive features. A key concept is the exterior magnet, surrounding all detector elements. Inside the magnet are a muon tracking system, a precision calorimeter, and a compact central tracker. This allows the muon momentum to be measured the air of the radiation shielded area outside the thick calorimeter, giving both high precision and robustness at high luminosity. A large magnet gives a large lever arm (at least 4 m) for precise muon momentum measurement. Placing the magnet outside also minimizes the material between tracker and calorimeters, so that the calorimeters are limited only by their inherent resolutions

  18. The Operational Experience of the Triple-GEM Detectors of the LHCb Muon System: Summary of 2 Years of Data Taking

    CERN Document Server

    Cardini, Alessandro; De Simone, Patrizia

    2012-01-01

    The LHCb muon system consists of more than a thousand gas detectors, mostly MWPC, located in five different stations. The Muon detector is used to define the muon trigger and to identify muons at the high-level triger and at the recontruction stage. The first station of the muon detector, located in front of the calorimetric system, is made of 274 chambers. The 12 most irradiated chambers, the ones closer to the beam pipe, are double triple-GEM detectors with pad readout. These detectors have an active area of 200x240 mm$^2$ and are routinely operated at rates close to 300 kHz/cm$^2$. With the gas mixture used (Ar/CO$_2$/CF$_4$ at 45/15/40) these detectors have the requested efficiency (>96% in a 20 ns time window for the logical OR of the two sensitive gaps) when operated at gains of about 2300. In this presentation we will report on the performance of these 24 triple-GEM detectors after more than 2 years of operation in the harsh LHCb conditions. We will also show some problems occurred during data taking, ...

  19. Diffraction measurements with a boron-based GEM neutron detector

    Science.gov (United States)

    Croci, Gabriele; Albani, Giorgia; Cazzaniga, Carlo; Perelli Cippo, Enrico; Schooneveld, Erik; Claps, Gerardo; Cremona, Anna; Grosso, Giovanni; Muraro, Andrea; Murtas, Fabrizio; Rebai, Marica; Scherillo, Antonella; Tardocchi, Marco; Gorini, Giuseppe

    2014-07-01

    The research of reliable substitutes of 3He detectors is an important task for the affordability of new neutron scattering instrumentation for future spallation sources like the European Spallation Source. GEM (Gas Electron Multiplier)-based detectors represent a valid alternative since they can combine high-rate capability, coverage of up to 1\\ \\text{m}^{2} area and good intrinsic spatial resolution (for this detector class it can be better than 0.5 mm). The first neutron diffraction measurements performed using a borated GEM detector are reported. The detector has an active area of 10 \\times 5\\ \\text{cm}^{2} and is equipped with a borated cathode. The GEM detector was read out using the standard ISIS Data Acquisition System. The comparison with measurements performed with standard 3He detectors shows that the broadening of the peaks measured on the diffractogram obtained with the GEM is 20-30% wider than the one obtained by 3He tubes but the active area of the GEM is twice that of 3He tubes. The GEM resolution is improved if half of its active area is considered. The signal-to-background ratio of the GEM is about 1.5 to 2 times lower than that of 3He. This measurement proves that GEM detectors can be used for neutron diffraction measurements and paves the way for their use at future neutron spallation sources.

  20. The GEMS-2 SEIS Experiment

    Science.gov (United States)

    Tillier, S.; De Raucourt, S.; Mimoun, D.; Lognonne, P.; Giardini, D.; Christensen, U. R.; Pike, W. T.; Banerdt, B.; Laudet, P.; Kerjean, L.; Hurst, K. J.; Zweifel, P.; Mance, D.; Roll, R.; Bierwirth, M.; Gagnepain-Beyneix, J.; Nibut, T.; Robert, O.; Gabsi, T.; Pot, O.; Lecomte, B.; Schibler, P.; Mocquet, A.; Garcia, R.

    2011-12-01

    The SEIS experiment is the primary payload of the Geophysical Monitoring Station (GEMS) Mission Proposal, submitted to NASA in the frame of the 2010 Discovery program, and recently selected for the phase A study. The objective of the GEMS SEIS experiment is the determination of the deep internal structure of Mars. In particular, geophysical parameters of first importance, such as the state (liquid/solid) and size of the core, as well as structure of the mantle and shape of discontinuities will be determined by the experiment. It will measure seismic activity in a very broad band of signal, from the tidal frequencies (0.05 mHz) up to the short period frequencies (50 Hz), to address the widest range of scientific questions, from the state of the inner core to the meteoritic rate measurement. Infrasound, which might be associated to dust devils and atmospheric discharge, will be also monitored. The instrument integrates a Very Broad Band (VBB) 3 axis seismometer, completed by another trihedron of MEMS short period seismometers, environmental sensors for pressure, wind and temperature, and an infrasound sensor is additionally considered. The sensors will be deployed on the Martian ground by a robotic arm from the Phoenix lander platform and protected by a wind and thermal shield. The sensor assembly, which contains all seismic sensors, the leveling system, as well as house-keeping and temperature measurements, will be deployed on the soil in order to allow the best possible mechanical coupling with the ground motion. Thanks to the wind and thermal shield, together with the sensors' specific containers (vacuum sphere for VBBs), long term VBB bias will be protected from both temperature and pressure variations (as well as passively compensated), allowing the sensor to operate in the rough Martian thermal environment. A dedicated electronics will manage the overall experiment and ultra-low noise, space qualified 24 bits A/D converters will perform the acquisition. The

  1. The climatology of carbon monoxide and water vapor on Mars as observed by CRISM and modeled by the GEM-Mars general circulation model

    Science.gov (United States)

    Smith, Michael D.; Daerden, Frank; Neary, Lori; Khayat, Alain

    2018-02-01

    Radiative transfer modeling of near-infrared spectra taken by the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) instrument onboard Mars Reconnaissance Orbiter (MRO) enables the column-integrated abundance of carbon monoxide (CO) and water vapor (H2O) to be retrieved. These results provide a detailed global description of the seasonal and spatial distribution of CO in the Mars atmosphere and new information about the interannual variability of H2O. The CRISM retrievals show the seasonally and globally averaged carbon monoxide mixing ratio to be near 800 ppm, but with strong seasonal variations, especially at high latitudes. At low latitudes, the carbon monoxide mixing ratio varies in response to the mean seasonal cycle of surface pressure and shows little variation with topography. At high latitudes, carbon monoxide is depleted in the summer hemisphere by a factor of two or more, while in the winter hemisphere there is relatively higher mixing ratio in regions with low-lying topography. Water vapor shows only modest interannual variations, with the largest observed difference being unusually dry conditions in the wake of the Mars Year 28 global dust storm. Modeling results from the GEM-Mars general circulation model generally reproduce the observed seasonal and spatial trends and provide insight into the underlying physical processes.

  2. Graphics gems V (Macintosh version)

    CERN Document Server

    Paeth, Alan W

    1995-01-01

    Graphics Gems V is the newest volume in The Graphics Gems Series. It is intended to provide the graphics community with a set of practical tools for implementing new ideas and techniques, and to offer working solutions to real programming problems. These tools are written by a wide variety of graphics programmers from industry, academia, and research. The books in the series have become essential, time-saving tools for many programmers.Latest collection of graphics tips in The Graphics Gems Series written by the leading programmers in the field.Contains over 50 new gems displaying some of t

  3. Graphics gems II

    CERN Document Server

    Arvo, James

    1991-01-01

    Graphics Gems II is a collection of articles shared by a diverse group of people that reflect ideas and approaches in graphics programming which can benefit other computer graphics programmers.This volume presents techniques for doing well-known graphics operations faster or easier. The book contains chapters devoted to topics on two-dimensional and three-dimensional geometry and algorithms, image processing, frame buffer techniques, and ray tracing techniques. The radiosity approach, matrix techniques, and numerical and programming techniques are likewise discussed.Graphics artists and comput

  4. What Controls the Vertical Distribution of Aerosol? Relationships Between Process Sensitivity in HadGEM3-UKCA and Inter-Model Variation from AeroCom Phase II

    Science.gov (United States)

    Kipling, Zak; Stier, Philip; Johnson, Colin E.; Mann, Graham W.; Bellouin, Nicolas; Bauer, Susanne E.; Bergman, Tommi; Chin, Mian; Diehl, Thomas; Ghan, Steven J.; hide

    2016-01-01

    The vertical profile of aerosol is important for its radiative effects, but weakly constrained by observations on the global scale, and highly variable among different models. To investigate the controlling factors in one particular model, we investigate the effects of individual processes in HadGEM3-UKCA and compare the resulting diversity of aerosol vertical profiles with the inter-model diversity from the AeroCom Phase II control experiment. In this way we show that (in this model at least) the vertical profile is controlled by a relatively small number of processes, although these vary among aerosol components and particle sizes. We also show that sufficiently coarse variations in these processes can produce a similar diversity to that among different models in terms of the global-mean profile and, to a lesser extent, the zonal-mean vertical position. However, there are features of certain models' profiles that cannot be reproduced, suggesting the influence of further structural differences between models. In HadGEM3-UKCA, convective transport is found to be very important in controlling the vertical profile of all aerosol components by mass. In-cloud scavenging is very important for all except mineral dust. Growth by condensation is important for sulfate and carbonaceous aerosol (along with aqueous oxidation for the former and ageing by soluble material for the latter). The vertical extent of biomass-burning emissions into the free troposphere is also important for the profile of carbonaceous aerosol. Boundary-layer mixing plays a dominant role for sea salt and mineral dust, which are emitted only from the surface. Dry deposition and below-cloud scavenging are important for the profile of mineral dust only. In this model, the microphysical processes of nucleation, condensation and coagulation dominate the vertical profile of the smallest particles by number (e.g. total CN >3 nm), while the profiles of larger particles (e.g. CN>100 nm) are controlled by the

  5. Game programming gems

    CERN Document Server

    DeLoura, Mark

    2000-01-01

    For the countless tasks involved in creating a game engine there are an equal number of possible solutions. But instead of spending hours and hours trying to develop your own answers, now you can find out how the pros do it! Game Programming Gems is a hands-on, comprehensive resource packed with a variety of game programming algorithms written by experts from the game industry and edited by Mark DeLoura, former software engineering lead for Nintendo of America, Inc. and now the newly appointed editor-in-chief of Game Developer magazine. From animation and artificial intelligence to Z-buffering, lighting calculations, weather effects, curved surfaces, mutliple layer Internet gaming, to music and sound effects, all of the major techniques needed to develop a competitive game engine are covered. Game Programming Gems is written in a style accessible to individuals with a range of expertise levels. All of the source code for each algorithm is included and can be used by advanced programmers immediately. For aspir...

  6. irradiated gem stones

    International Nuclear Information System (INIS)

    Salama, S.S.M

    2006-01-01

    gem stones are those stones which have beauty that can be based on its color, transparency, brilliance (degree to which light is scattered) and the crystalline perfection (no minerals or other inclusions). topaz AL 2 SiO 4 (F,OH) 2 Aluminum fluoro-hydroxyl -silicate, it belongs to class silicates and subclass cyclo silicates and it is used mainly as gemstones, it is most common irradiated gem on the market. high energy such as neutrons, have enough energy to produce color centres .irradiation is most often carried out in nuclear reactors (high-energy neutrons). irradiation of topaz in the egyptian research reactor (ETRR-2) by neutrons changes its cloudy white color to a reddish pink which could be changed to blue by heating. nuclear reactions inside the irradiated stones produce radioisotopes. resulting to residual radioactivity. residual radioactivity is potentially a problem;therefore stones have to be stored in storage for a period of time to reduce the residual radioactivity aiming to reach the safety level of transportation. the storage time of the stones is dependent on trace element concentrations connected with their life-times in topaz . therefore, inspection of the trace elements in the stones and their half-life times are essential before irradiation

  7. OpenGeoSys-GEMS: Hybrid parallelization of a reactive transport code with MPI and threads

    Science.gov (United States)

    Kosakowski, G.; Kulik, D. A.; Shao, H.

    2012-04-01

    OpenGeoSys-GEMS is a generic purpose reactive transport code based on the operator splitting approach. The code couples the Finite-Element groundwater flow and multi-species transport modules of the OpenGeoSys (OGS) project (http://www.ufz.de/index.php?en=18345) with the GEM-Selektor research package to model thermodynamic equilibrium of aquatic (geo)chemical systems utilizing the Gibbs Energy Minimization approach (http://gems.web.psi.ch/). The combination of OGS and the GEM-Selektor kernel (GEMS3K) is highly flexible due to the object-oriented modular code structures and the well defined (memory based) data exchange modules. Like other reactive transport codes, the practical applicability of OGS-GEMS is often hampered by the long calculation time and large memory requirements. • For realistic geochemical systems which might include dozens of mineral phases and several (non-ideal) solid solutions the time needed to solve the chemical system with GEMS3K may increase exceptionally. • The codes are coupled in a sequential non-iterative loop. In order to keep the accuracy, the time step size is restricted. In combination with a fine spatial discretization the time step size may become very small which increases calculation times drastically even for small 1D problems. • The current version of OGS is not optimized for memory use and the MPI version of OGS does not distribute data between nodes. Even for moderately small 2D problems the number of MPI processes that fit into memory of up-to-date workstations or HPC hardware is limited. One strategy to overcome the above mentioned restrictions of OGS-GEMS is to parallelize the coupled code. For OGS a parallelized version already exists. It is based on a domain decomposition method implemented with MPI and provides a parallel solver for fluid and mass transport processes. In the coupled code, after solving fluid flow and solute transport, geochemical calculations are done in form of a central loop over all finite

  8. Geoengineering by stratospheric SO2 injection: results from the Met Office HadGEM2 climate model and comparison with the Goddard Institute for Space Studies ModelE

    Directory of Open Access Journals (Sweden)

    B. Kravitz

    2010-07-01

    Full Text Available We examine the response of the Met Office Hadley Centre's HadGEM2-AO climate model to simulated geoengineering by continuous injection of SO2 into the lower stratosphere, and compare the results with those from the Goddard Institute for Space Studies ModelE. Despite the differences between the models, we find a broadly similar geographic distribution of the response to geoengineering in both models in terms of near-surface air temperature and mean June–August precipitation. The simulations also suggest that significant changes in regional climate would be experienced even if geoengineering was successful in maintaining global-mean temperature near current values, and both models indicate rapid warming if geoengineering is not sustained.

  9. CCD readout of GEM-based neutron detectors

    CERN Document Server

    Fraga, F A F; Fetal, S T G; Fraga, M; Guérard, B; Manzini, G; Margato, L M S; Oed, A; Policarpo, Armando; Vuure, T V

    2002-01-01

    We report on the optical readout of the gas electron multiplier (GEM) operated with a gaseous mixture suitable for the detection of thermal neutrons: sup 3 He-CF sub 4. A CCD system operating in the 400-1000 nm band was used to collect the light. Spectroscopic data on the visible and NIR scintillation of He-CF sub 4 are presented. Images of the tracks of the proton and triton recorded with a triple GEM detector are also shown.

  10. Mexican gems as thermoluminescent dosimeters

    International Nuclear Information System (INIS)

    Azorin N, J.

    1979-01-01

    The possibility of using naturally ocurring mexican gems as thermoluminescent dosimeters (TLD) was investigated. Twelve types of gems were irradiated with X and gamma rays in order to determinate their dosimetric properties. Three of these gems showed favorable thermoluminescent characteristics compared with commercial thermoluminescent dosimeters. The plots of their thermoluminescent response as a function of gamma dose are straight lines on full log paper in the dose range 10 -2 to 10 2 Gy. The energy dependence is very strong to low energies of the radiation. Their fading was found to be about 5%/yr. and they may be annealed as reused without loss in sensitivity. Therefore, these gems can be used as X and gamma radiation dosimeters. (author)

  11. Evaluation of the Cloud Fields in the UK Met Office HadGEM3-UKCA Model Using the CCCM Satellite Data Product to Advance Our Understanding of the Influence of Clouds on Tropospheric Composition and Chemistry

    Science.gov (United States)

    Varma, Sunil; Voulgarakis, Apostolos; Liu, Hongyu; Crawford, James H.; White, James

    2016-01-01

    To determine the role of clouds in driving inter-annual and inter-seasonal variability of trace gases in the troposphere and lower stratosphere with a particular focus on the importance of cloud modification of photolysis. To evaluate the cloud fields and their vertical distribution in the HadGEM3 model utilizing CCCM, a unique 3-D cloud data product merged from multiple A-Train satellites (CERES, CloudSat, CALIPSO, and MODIS) developed at the NASA Langley Research Center.

  12. The HadGEM2-ES implementation of CMIP5 centennial simulations

    Directory of Open Access Journals (Sweden)

    C. D. Jones

    2011-07-01

    Full Text Available The scientific understanding of the Earth's climate system, including the central question of how the climate system is likely to respond to human-induced perturbations, is comprehensively captured in GCMs and Earth System Models (ESM. Diagnosing the simulated climate response, and comparing responses across different models, is crucially dependent on transparent assumptions of how the GCM/ESM has been driven – especially because the implementation can involve subjective decisions and may differ between modelling groups performing the same experiment. This paper outlines the climate forcings and setup of the Met Office Hadley Centre ESM, HadGEM2-ES for the CMIP5 set of centennial experiments. We document the prescribed greenhouse gas concentrations, aerosol precursors, stratospheric and tropospheric ozone assumptions, as well as implementation of land-use change and natural forcings for the HadGEM2-ES historical and future experiments following the Representative Concentration Pathways. In addition, we provide details of how HadGEM2-ES ensemble members were initialised from the control run and how the palaeoclimate and AMIP experiments, as well as the "emission-driven" RCP experiments were performed.

  13. Embedding the guideline elements model in web ontology language.

    Science.gov (United States)

    Tran, Nam; Michel, George; Krauthammer, Michael; Shiffman, Richard N

    2009-11-14

    The Guideline Elements Model (GEM) uses XML to represent the heterogeneous knowledge contained in clinical practice guidelines. GEM has important applications in computer aided guideline authoring and clinical decision support systems. However, its XML representation format could limit its potential impact, as semantic web ontology languages, such as OWL, are becoming major knowledge representation frameworks in medical informatics. In this work, we present a faithful translation of GEM from XML into OWL. This translation is intended to keep the knowledge model of GEM intact, as this knowledge model has been carefully designed and has become a recognized standard. An OWL representation would make GEM more applicable in medical informatics systems that rely on semantic web. This work will also be the initial step in making GEM a guideline recommendation ontology.

  14. PLC-controlled cryostats for the BlackGEM and MeerLICHT detectors

    Science.gov (United States)

    Raskin, Gert; Morren, Johan; Pessemier, Wim; Bloemen, Steven; Klein-Wolt, Marc; Roelfsema, Ronald; Groot, Paul; Aerts, Conny

    2016-08-01

    BlackGEM is an array of telescopes, currently under development at the Radboud University Nijmegen and at NOVA (Netherlands Research School for Astronomy). It targets the detection of the optical counterparts of gravitational waves. The first three BlackGEM telescopes are planned to be installed in 2018 at the La Silla observatory (Chile). A single prototype telescope, named MeerLICHT, will already be commissioned early 2017 in Sutherland (South Africa) to provide an optical complement for the MeerKAT radio array. The BlackGEM array consists of, initially, a set of three robotic 65-cm wide-field telescopes. Each telescope is equipped with a single STA1600 CCD detector with 10.5k x 10.5k 9-micron pixels that covers a 2.7 square degrees field of view. The cryostats for housing these detectors are developed and built at the KU Leuven University (Belgium). The operational model of BlackGEM requires long periods of reliable hands-off operation. Therefore, we designed the cryostats for long vacuum hold time and we make use of a closed-cycle cooling system, based on Polycold PCC Joule-Thomson coolers. A single programmable logic controller (PLC) controls the cryogenic systems of several BlackGEM telescopes simultaneously, resulting in a highly reliable, cost-efficient and maintenance-friendly system. PLC-based cryostat control offers some distinct advantages, especially for a robotic facility. Apart of temperature monitoring and control, the PLC also monitors the vacuum quality, the power supply and the status of the PCC coolers (compressor power consumption and temperature, pressure in the gas lines, etc.). Furthermore, it provides an alarming system and safe and reproducible procedures for automatic cool down and warm up. The communication between PLC and higher-level software takes place via the OPC-UA protocol, offering a simple to implement, yet very powerful interface. Finally, a touch-panel display on the PLC provides the operator with a user-friendly and robust

  15. A large area GEM detector

    CERN Document Server

    Duarte Pinto, Serge; Brock, Ian; Croci, Gabriele; David, Eric; de Oliveira, Rui; Pinchasik, Bat-El; Ropelewski, Leszek; Sauli, Fabio; van Stenis, Miranda

    2009-01-01

    A prototype triple GEM detector has been constructed with an area of similar to 2000 cm(2), based on foils of 66 cm x 66 cm. GEMS of such dimensions have not been made before, and innovations to the existing technology were made to build this detector. A single-mask technique overcomes the cumbersome practice of alignment of two masks, which limits the achievable lateral size. Refinement of this technique results in foils with performance similar to traditional GEMS, while lowering cost and complexity of production. In a splicing procedure, foils are glued over a narrow seam, thus obtaining a larger foil. This procedure was shown not to affect the performance of the GEMS. The seam can be as narrow as 2 mm, mechanically strong enough to withstand the necessary stretching tension, and sufficiently flat to maintain homogeneous electric fields in the gas volumes above and below the foil. These innovations should make the manufacture Of GEM foils of 1 m(2) and beyond possible. With the planned high luminosity upgr...

  16. A large ungated TPC with GEM amplification

    Science.gov (United States)

    Berger, M.; Ball, M.; Fabbietti, L.; Ketzer, B.; Arora, R.; Beck, R.; Böhmer, F. V.; Chen, J.-C.; Cusanno, F.; Dørheim, S.; García, F.; Hehner, J.; Herrmann, N.; Höppner, C.; Kaiser, D.; Kis̆, M.; Kleipa, V.; Konorov, I.; Kunkel, J.; Kurz, N.; Leifels, Y.; Müllner, P.; Münzer, R.; Neubert, S.; Rauch, J.; Schmidt, C. J.; Schmitz, R.; Soyk, D.; Vandenbroucke, M.; Voss, B.; Walther, D.; Zmeskal, J.

    2017-10-01

    A Time Projection Chamber (TPC) is an ideal device for the detection of charged particle tracks in a large volume covering a solid angle of almost 4 π. The high density of hits on a given particle track facilitates the task of pattern recognition in a high-occupancy environment and in addition provides particle identification by measuring the specific energy loss for each track. For these reasons, TPCs with Multiwire Proportional Chamber (MWPC) amplification have been and are widely used in experiments recording heavy-ion collisions. A significant drawback, however, is the large dead time of the order of 1 ms per event generated by the use of a gating grid, which is mandatory to prevent ions created in the amplification region from drifting back into the drift volume, where they would severely distort the drift path of subsequent tracks. For experiments with higher event rates this concept of a conventional TPC operating with a triggered gating grid can therefore not be applied without a significant loss of data. A continuous readout of the signals is the more appropriate way of operation. This, however, constitutes a change of paradigm with considerable challenges to be met concerning the amplification region, the design and bandwidth of the readout electronics, and the data handling. A mandatory prerequisite for such an operation is a sufficiently good suppression of the ion backflow from the avalanche region, which otherwise limits the tracking and particle identification capabilities of such a detector. Gas Electron Multipliers (GEM) are a promising candidate to combine excellent spatial resolution with an intrinsic suppression of ions. In this paper we describe the design, construction and the commissioning of a large TPC with GEM amplification and without gating grid (GEM-TPC). The design requirements have driven innovations in the construction of a light-weight field-cage, a supporting media flange, the GEM amplification and the readout system, which are

  17. Characterization of the water diffusion in GEM foil material

    Science.gov (United States)

    Benussi, L.; Bianco, S.; Saviano, G.; Muhammad, S.; Piccolo, D.; Raffone, G.; Caponero, M.; Passamonti, L.; Pierluigi, D.; Russo, A.; Primavera, F.; Cerbelli, S.; Lalli, A.; Valente, M.; Ferrini, M.; Teissandier, B.; Taborelli, M.; Parvis, M.; Grassini, S.; Tirilló, J.; Sarasini, F.; Franchi, A. V.

    2018-02-01

    Systematic studies on the GEM foil material are performed to measure the moisture diffusion rate and saturation level. These studies are important because the presence of this compound inside the detector' s foil can possibly change its mechanical and electrical properties, and in such a way, the detector performance can be affected. To understand this phenomenon, a model is developed with COMSOL Multiphysics v. 4.3 [1], which described the adsorption and diffusion within the geometry of GEM foil, the concentration profiles and the time required to saturate the foil. The COMSOL model is verified by experimental observations on a GEM foil sample. This note will describe the model and its experimental verification results.

  18. Integrated Farm System Model Version 4.3 and Dairy Gas Emissions Model Version 3.3 Software development and distribution

    Science.gov (United States)

    Modeling routines of the Integrated Farm System Model (IFSM version 4.2) and Dairy Gas Emission Model (DairyGEM version 3.2), two whole-farm simulation models developed and maintained by USDA-ARS, were revised with new components for: (1) simulation of ammonia (NH3) and greenhouse gas emissions gene...

  19. Gem and mineral identification using GL Gem Raman and comparison with other portable instruments

    Science.gov (United States)

    Culka, Adam; Hyršl, Jaroslav; Jehlička, Jan

    2016-11-01

    Several mainly silicate minerals in their gemstone varieties have been analysed by the Gem Raman portable system by Gemlab R&T, Vancouver, Canada, in order to ascertain the general performance of this relatively non-expensive tool developed exactly for the purpose of gemstone identification. The Raman spectra of gemstones acquired by this system have been subsequently critically compared with the data obtained by several other portable or handheld Raman instruments. The Raman spectra acquired with the Gem Raman instrument were typically of lesser quality when compared with the spectra taken by other instruments. Characteristic features such as steep baseline probably due to the fluorescence of the minerals, Raman bands much broader and therefore less resolved closely located Raman bands, and generally greater shifts of the band positions from the reference values were encountered. Some gemstone groups such as rubies did not provide useful Raman spectra at all. Nevertheless, general identification of gemstones was possible for a selection of gemstones.

  20. GEM/POPs: a global 3-D dynamic model for semi-volatile persistent organic pollutants ─ Part 2: Global transports and budgets of PCBs

    Directory of Open Access Journals (Sweden)

    L. A. Barrie

    2007-08-01

    Full Text Available Global transports and budgets of three PCBs were investigated with a 3-D dynamic model for semi-volatile persistent organic pollutants – GEM/POPs. Dominant pathways were identified for PCB transports in the atmosphere with a transport flux peaking below 8 km for gaseous and 14 km for particulate PCB28, and peaking below 4 km for gaseous and 6 km for particulate PCB180. The inter-continental transports of PCBs in the Northern Hemisphere (NH are dominated in the zonal direction with their route changes regulated seasonally by the variation of westerly jet. The transport pathways from Europe and North Atlantic contributed the most PCBs to the Arctic. Inter-hemispheric transports of PCBs originated from the regions of Europe, Asia and North America in three different flow-paths, accompanying with easterly jet, Asian monsoon winds and trade winds. PCBs from the Southern Hemisphere (SH could also be exported into the NH. According to the PCB emissions of year 2000, Europe, North America and Asia are the three largest sources of the three PCBs, contributing to the global background concentrations in the atmosphere, soil and water. Globally, PCB28 in soil and water has become a comparable source to the anthropogenic emissions while heavier PCBs such as PCB153 and 180 are still transporting into soil and water. For all three congeners, particulate PCBs are concentrated in the higher levels than gaseous PCBs. More than half of the particulate PCB28 could reach up to the stratosphere, while most of the heavier counter-parts (PCB153 and PCB180 are stored in the troposphere including boundary layer with more than 99% gaseous PCB180 below 6 km.

  1. redGEM: Systematic reduction and analysis of genome-scale metabolic reconstructions for development of consistent core metabolic models.

    Directory of Open Access Journals (Sweden)

    Meric Ataman

    2017-07-01

    Full Text Available Genome-scale metabolic reconstructions have proven to be valuable resources in enhancing our understanding of metabolic networks as they encapsulate all known metabolic capabilities of the organisms from genes to proteins to their functions. However the complexity of these large metabolic networks often hinders their utility in various practical applications. Although reduced models are commonly used for modeling and in integrating experimental data, they are often inconsistent across different studies and laboratories due to different criteria and detail, which can compromise transferability of the findings and also integration of experimental data from different groups. In this study, we have developed a systematic semi-automatic approach to reduce genome-scale models into core models in a consistent and logical manner focusing on the central metabolism or subsystems of interest. The method minimizes the loss of information using an approach that combines graph-based search and optimization methods. The resulting core models are shown to be able to capture key properties of the genome-scale models and preserve consistency in terms of biomass and by-product yields, flux and concentration variability and gene essentiality. The development of these "consistently-reduced" models will help to clarify and facilitate integration of different experimental data to draw new understanding that can be directly extendable to genome-scale models.

  2. The gas electron multiplier (GEM)

    CERN Document Server

    Bouclier, Roger; Dominik, Wojciech; Hoch, M; Labbé, J C; Million, Gilbert; Ropelewski, Leszek; Sauli, Fabio; Sharma, A

    1996-01-01

    We describe operating priciples and results obtained with a new detector component: the Gas Electrons Multiplier (GEM). Consisting of a thin composite sheet with two metal layers separated by a thin insulator, and pierced by a regular matrix of open channels, the GEM electrode, inserted on the path of electrons in a gas detector, allows to transfer the charge with an amplification factor approaching ten. Uniform response and high rate capability are demonstrated. Coupled to another device, multiwire or micro-strip chamber, the GEM electrode permit to obtain higher gains or less critical operation; separation of the sensitive (conversion) volume and the detection volume has other advantages, as a built-in delay (useful for triggering purposes) and the possibility of applying high fields on the photo-cathode of ring imaging detectors to improve efficiency. Multiple GEM grids in the same gas volume allow to obtain large amplification factors in a succession of steps, leading to the realization of an effective ga...

  3. Progress on large area GEMs

    CERN Document Server

    Pinto, Serge Duarte; Alfonsi, Matteo; Brock, Ian; Croci, Gabriele; David, Eric; De Oliveira, Rui; Ropelewski, Leszek; van Stenis, Miranda

    2009-01-01

    In 2008, a triple GEM detector prototype with an area of ~2000 cm2 has been constructed, based on foils of 66*66 cm. GEMs of such dimensions had not been made before, and innovations to the existing technology were introduced to build this detector. This paper discusses these innovations and presents further work on large area GEM development. A single-mask technique overcomes the cumbersome practice of alignment of two masks, which limits the achievable lateral size. The holes obtained with this technique are conical, and have a so-called rim, a small insulating clearance around the hole in the substrate. Further refinements of this technique allow greater control over the shape of holes and the size of rims. Also, an improvement in homogeneity over large areas is expected. Simulation studies have been done to examine the effect of hole shape on the behavior of GEMs. Such studies can help understanding how to use new enhancements of the technique to optimize performance. Many potential applications for large...

  4. HydroGEM, a hydrogen fuelled utility vehicle. Case study

    International Nuclear Information System (INIS)

    Hoevenaars, A.J.; Kraaij, G.J.; De Bruijne, M.; Weeda, M.

    2010-02-01

    This report describes the conversion of a Global Electric Motorcars (GEM, a Chrysler company) electric utility vehicle into a Fuel Cell Vehicle called HydroGEM, at the Energy research Centre of the Netherlands (ECN). The report is prepared as a case study within the framework of Task 18 on 'Evaluation of Integrated Hydrogen Systems' of the IEA Hydrogen Implementing Agreement. The vehicle's fuel cell system was designed in 2005, manufactured and built into the vehicle in 2006 and operated from 2007 onwards. The design-choices, assembly, operation and maintenance-issues are presented and discussed.

  5. Comparison of the HadGEM2 climate-chemistry model against in-situ and SCIAMACHY atmospheric methane data

    OpenAIRE

    G. D. Hayman; F. M. O'Connor; M. Dalvi; D. B. Clark; N. Gedney; C. Huntingford; C. Prigent; M. Buchwitz; O. Schneising; J. P. Burrows; C. Wilson; N. Richards; M. Chipperfield

    2014-01-01

    Wetlands are a major emission source of methane (CH4) globally. In this study, we have evaluated wetland emission estimates derived using the UK community land surface model (JULES, the Joint UK Land Earth Simulator) against atmospheric observations of methane, including, for the first time, total methane columns derived from the SCIAMACHY instrument on board the ENVISAT satellite. Two JULES wetland emission estimates were investigated: (a) from an ...

  6. Readout of TPC Tracking Chambers with GEMs and Pixel Chip

    Energy Technology Data Exchange (ETDEWEB)

    Kadyk, John; Kim, T.; Freytsis, M.; Button-Shafer, J.; Kadyk, J.; Vahsen, S.E.; Wenzel, W.A.

    2007-12-21

    Two layers of GEMs and the ATLAS Pixel Chip, FEI3, have been combined and tested as a prototype for Time Projection Chamber (TPC) readout at the International Linear Collider (ILC). The double-layer GEM system amplifies charge with gain sufficient to detect all track ionization. The suitability of three gas mixtures for this application was investigated, and gain measurements are presented. A large sample of cosmic ray tracks was reconstructed in 3D by using the simultaneous timing and 2D spatial information from the pixel chip. The chip provides pixel charge measurement as well as timing. These results demonstrate that a double GEM and pixel combination, with a suitably modified pixel ASIC, could meet the stringent readout requirements of the ILC.

  7. SEARCHING FOR BINARY Y DWARFS WITH THE GEMINI MULTI-CONJUGATE ADAPTIVE OPTICS SYSTEM (GeMS)

    International Nuclear Information System (INIS)

    Opitz, Daniela; Tinney, C. G.; Faherty, Jacqueline K.; Sweet, Sarah; Gelino, Christopher R.; Kirkpatrick, J. Davy

    2016-01-01

    The NASA Wide-field Infrared Survey Explorer (WISE) has discovered almost all the known members of the new class of Y-type brown dwarfs. Most of these Y dwarfs have been identified as isolated objects in the field. It is known that binaries with L- and T-type brown dwarf primaries are less prevalent than either M-dwarf or solar-type primaries, they tend to have smaller separations and are more frequently detected in near-equal mass configurations. The binary statistics for Y-type brown dwarfs, however, are sparse, and so it is unclear if the same trends that hold for L- and T-type brown dwarfs also hold for Y-type ones. In addition, the detection of binary companions to very cool Y dwarfs may well be the best means available for discovering even colder objects. We present results for binary properties of a sample of five WISE Y dwarfs with the Gemini Multi-Conjugate Adaptive Optics System. We find no evidence for binary companions in these data, which suggests these systems are not equal-luminosity (or equal-mass) binaries with separations larger than ∼0.5–1.9 AU. For equal-mass binaries at an age of 5 Gyr, we find that the binary binding energies ruled out by our observations (i.e., 10 42 erg) are consistent with those observed in previous studies of hotter ultra-cool dwarfs

  8. Use of aluminium plates to simulate the dosimetry of gems during e-beam irradiation

    International Nuclear Information System (INIS)

    Fortes, Marcio Z.; Sousa, Fernando N.C. de; Boente, Otavio C.; Sousa, Nuno R.A.

    2009-01-01

    The e-beam technology is used in the industrial irradiation of several products like turf, sterilization of medical products, cosmetics, polymers, food, and gems. More than 70% of the gems commercialized in the world receive treatments similar to those present in nature, including heat, and irradiation, in order to improve their value. Since aluminum has a density similar to that of several commercial gems, this paper presents a study of the penetration of electrons in calibrated aluminum plates simulating several different thicknesses ranging from 5 to 30 mm, and comparing with the one obtained in gems. This allows the monitoring of the dose received by gems during irradiation with e-beam systems measuring the delivered surface dose. This procedure is very important for industrial processing of stones due to the irregularities present on most gems, what makes dosimetry a very complex task. The determination of the thicknesses of the gems for which the surface dose is the lowest dose on the whole product assures the precise determination of the minimum dose received by the gems during industrial processing. (author)

  9. Possible Gems and Ultra-Fine Grained Polyphase Units in Comet Wild 2.

    Science.gov (United States)

    Gainsforth, Z.; Butterworth, A. L.; Jilly-Rehak, C. E.; Westphal, A. J.; Brownlee, D. E.; Joswiak, D.; Ogliore, R. C.; Zolensky, M. E.; Bechtel, H. A.; Ebel, D. S.; hide

    2016-01-01

    GEMS and ultrafine grained polyphase units (UFG-PU) in anhydrous IDPs are probably some of the most primitive materials in the solar system. UFG-PUs contain nanocrystalline silicates, oxides, metals and sulfides. GEMS are rounded approximately 100 nm across amorphous silicates containing embedded iron-nickel metal grains and sulfides. GEMS are one of the most abundant constituents in some anhydrous CPIDPs, often accounting for half the material or more. When NASA's Stardust mission returned with samples from comet Wild 2 in 2006, it was thought that UFG-PUs and GEMS would be among the most abundant materials found. However, possibly because of heating during the capture process in aerogel, neither GEMS nor UFG-PUs have been clearly found.

  10. GEM the gas electron multiplier

    CERN Document Server

    Sauli, Fabio

    1997-01-01

    We describe the basic structure and operation of a new device, the Gas Electron Multiplier. Consisting in a polymer foil, metal-clad on both sides and perforated by a high density of holes, the GEM mesh allows to pre-amplify charges released in the gas with good uniformity and energy. Coupled to a micro-strip plate, the pre-amplification element allows to preserve high rate capability and resolution at considerably lower operating voltages, thus completely eliminating discharges and instabilities. Several GEM grids can be operated in cascade; charge gains are large enough to allow detection of signals in the ionization mode on the last element, permitting the use of a simple printed circuit as read-out electrode. Two-dimensional read-out can then be easily implemented. A new generation of simple, reliable and cheap fast position sensitive detectors seems at hand.

  11. Science's gem: Diamond science 2009

    OpenAIRE

    Mainwood, A.; Newton, M. E.; Stoneham, M.

    2009-01-01

    Natural diamond has been valued for its appearance and mechanical properties for at least two thousand years. As a gem stone diamond is unsurpassed. However, scientific work, especially in the last 20 years, has demonstrated that diamond has numerous surprising properties and many unique ones. Some of the extreme properties have been known for many years, but the true scale of diamond's other highly desirable features is still only coming to light as control in the synthesis of diamond, and h...

  12. The Greenhouse Gases. UNEP/GEMS Environment Library No. 1.

    Science.gov (United States)

    United Nations Environment Programme, Nairobi (Kenya).

    Since the United Nations Environment Program (UNEP) was created, more than a dozen years ago, public understanding of the environmental issues confronting our planet has increased enormously. The Global Environment Monitoring System (GEMS) has provided several environmental assessments including urban air pollution, climate modification,…

  13. Progress on large area GEMs (VCI 2010)

    CERN Document Server

    Villa, Marco; Alfonsi, Matteo; Brock, Ian; Croci, Gabriele; David, Eric; de Oliveira, Rui; Ropelewski, Leszek; Taureg, Hans; van Stenis, Miranda

    2011-01-01

    The Gas Electron Multiplier (GEM) manufacturing technique has recently evolved to allow the production of large area GEMs. A novel approach based on single mask photolithography eliminates the mask alignment issue, which limits the dimensions in the traditional double mask process. Moreover, a splicing technique overcomes the limited width of the raw material. Stretching and handling issues in large area GEMs have also been addressed. Using the new improvements it was possible to build a prototype triple-GEM detector of ~ 2000 cm2 active area, aimed at an application for the TOTEM T1 upgrade. Further refinements of the single mask technique give great control over the shape of the GEM holes and the size of the rims, which can be tuned as needed. In this framework, simulation studies can help to understand the GEM behavior depending on the hole shape.

  14. Quality Control (QC2) of Gas Electron Multiplier (GEM) for GE1/1 at CMS Experiment

    CERN Document Server

    Sharma, Archana

    2016-01-01

    Gas Electron Multiplier (GEM) is a gas ionization detector that detect charged particles and will be implemented on CMS system. It is designed to improve muon trigger and tracking performance at high luminosity after the second Long Shutdown (LS2). For my project, GEM foils, a component of the Triple GEM detector have been studied. In order to pass the test, the foils need to run in the Fast Test and Long Test of QC2.

  15. Leading a successful iGEM team.

    Science.gov (United States)

    Materi, Wayne

    2012-01-01

    The International Genetically Engineered Machines (iGEM) competition allows undergraduate teams to develop projects in synthetic biology within the context of a large, international Jamboree. Organizing and managing a successful iGEM team is an exercise in advanced agile project development. While many of the principles applicable to such teams are derived from management of agile software teams, iGEM presents several unique challenges.

  16. CMS Technical Design Report for the Muon Endcap GEM Upgrade

    CERN Document Server

    AUTHOR|(CDS)2108476; Safonov, A; Sharma, A; Tytgat, M; CERN. Geneva. The LHC experiments Committee; LHCC

    2015-01-01

    This report describes both the technical design and the expected performance of the Phase-II upgrade, using Gas Electron Multiplier (GEM) detectors, of the first endcap station of the CMS muon system. The upgrade is targeted for the second long shutdown of the CERN LHC and is designed to improve the muon trigger and tracking performance at high luminosity. The GEM detectors will add redundancy to the muon system in the 1.6 < |η| < 2.2 pseudorapidity region, where the amount of detection layers is lowest while the background rates are highest and the bending of the muon trajectories due to the CMS magnetic field is small. GEM detectors have been identified as a suitable technology to operate in the high radiation environment present in that region. The first muon endcap station will be instrumented with a double layer of triple-GEM chambers in the 1.6 < |η| < 2.2 region. The detector front-end electronics uses the custom designed VFAT3 chip to provide both fast input for the level-1 muon trigger ...

  17. Continuous health monitoring of Graphite Epoxy Motorcases (GEM)

    Science.gov (United States)

    Finlayson, Richard D.; Schaafsma, David T.; Shen, H. Warren; Carlos, Mark F.; Miller, Ronnie K.; Shepherd, Brent

    2001-07-01

    Following the explosion of Delta 241 (IIR-1) on January 17th, 1997, the failure investigation board concluded that the Graphite Epoxy Motorcases (GEM's) should be inspected for damage just prior to launch. Subsequent investigations and feedback from industry led to an Aerospace Corporation proposal to instrument the entire fleet of GEM's with a continuous health monitoring system. The period of monitoring would extend from the initial acceptance testing through final erection on the launch pad. As this proposal demonstrates, (along with the increasing use of advanced composite materials in aircraft, automobiles, military hardware, and aerospace components such as rocket motorcases) a sizable need for composite health assessment measures exist. Particularly where continuous monitoring is required for the detection of damage from impacts and other sources of high mechanical and thermal stresses. Even low-momentum impacts can lead to barely visible impact damage (BVID), corresponding to a significant weakening of the composite. This damage, undetectable by visual inspection, can in turn lead to sudden and catastrophic failure when the material is subjected to a normal operating load. There is perhaps no system with as much potential for truly catastrophic failure as a rocket motor. We will present an update on our ongoing efforts with the United States Air Force Delta II Program Office, and The Aerospace Corporation. This will cover the development of a local, portable, surface-mounted, fiberoptic sensor based impact damage monitor designed to operate on a Delta II GEM during transport, storage, and handling. This system is designed to continuously monitor the GEMs, to communicate wirelessly with base stations and maintenance personnel, to operate autonomously for extended periods, and to fit unobtrusively on the GEM itself.

  18. Game engine gems 2

    CERN Document Server

    Lengyel, Eric

    2011-01-01

    GRAPHICS AND RENDERINGFast Computation of Tight-Fitting Oriented Bounding Boxes; Thomas Larsson (Senior Lecturer at Mälardalen University) & Linus Källberg (Lecturer at Mälardalen University)Modeling, Lighting, and Rendering Techniques for Volumetric Clouds; Frank Kane (Founder of Sundog Software, LLC)Simulation of Night-Vision and Infrared Sensors; Frank Kane (Founder of Sundog Software, LLC)Screen-Space Classification for Efficient Deferred Shading; Balor Knight (Senior Principal Programmer at Black Rock Studio), Matthew Ritchie (Principal Programmer at Black Rock Studio), George Parrish (Se

  19. GPU Computing Gems Emerald Edition

    CERN Document Server

    Hwu, Wen-mei W

    2011-01-01

    ".the perfect companion to Programming Massively Parallel Processors by Hwu & Kirk." -Nicolas Pinto, Research Scientist at Harvard & MIT, NVIDIA Fellow 2009-2010 Graphics processing units (GPUs) can do much more than render graphics. Scientists and researchers increasingly look to GPUs to improve the efficiency and performance of computationally-intensive experiments across a range of disciplines. GPU Computing Gems: Emerald Edition brings their techniques to you, showcasing GPU-based solutions including: Black hole simulations with CUDA GPU-accelerated computation and interactive display of

  20. ROLE OF GEMS IN INDIAN MEDICINE

    Science.gov (United States)

    Murthy, S.R.N.

    1991-01-01

    This paper is the first attempt in introducing the medicinal importance of gems as found in the Sanskrit text ‘Rasaratnasamuccaya’, which has been rendered an English translation here. The modern physicians and gemologists will find this study quite useful in continuing research and, thus, develop a new field of gem medicine. PMID:22556526

  1. Design approach for granular emulsion mixes (GEMS)

    CSIR Research Space (South Africa)

    Grobler, JE

    1994-10-01

    Full Text Available ) is presented. An “asphalt” approach is used in the design of stabilised GEMS with residual binder contents of more than 1,5%, using design methods such as the Marshall mix design method. A “gravel” approach is used in the design of modified GEMS with residual...

  2. Evaluation of the UK Met Office's HadGEM3-RA and HadRM3P regional climate models within South America-CORDEX simulations: ENSO related interannual precipitation variability

    Science.gov (United States)

    Bozkurt, D.; Rojas, M.

    2014-12-01

    This study aims to investigate and compare the ability of the UK Met Office's HadGEM3-RA and HadRM3P regional climate models (RCMs) to simulate mean and interannual variability of precipitation over South America with a special focus on Chile. The HadGEM3-RA is a regional version of the newly developed HadGEM3 global model and the HadRM3P is based on the earlier HadCM3 global model. The RCMs simulations were carried out at 0.44o x 0.44o degree resolution over South America-CORDEX domain for the period 1989-2008. The initial and boundary conditions were provided by ERA-Interim Reanalysis data available at 6-h intervals with a resolution of 1.5o x 1.5o in the horizontal and 37 pressure levels. We compare the results against a number of observational datasets, including gridded dataset of CRU, UDEL, TRMM and GPCP. Moreover, available station data is derived from Direccion General de Aguas (DGA) mainly for Central Chile, which is the heartland of Chile with the highest population and important economic activities. The analysis is mainly focused on evaluating the abilities of the RCMs in simulating spatial pattern and ENSO related precipitation variability in different subregions of South America-CORDEX domain. In general, both RCMs have a good skill in reproducing spatial pattern and annual cycle of observed precipitation in climatically different subregions. However, both RCMs tend to underestimate precipitation in the Amazon Basin, which is more pronounced in the HadRM3P simulations. On the contrary, the RCMs tend to overestimate the precipitation over the Andes and southern Chile. The overestimation could be related to the physical core of the RCMs, but the discrepancies could also arise due to insufficient station network, especially in the mountainous areas, potentially yielding smaller precipitation quantities in the observed data than the true ones. In terms of interannual variability, the models capture ENSO related wet and dry interannual precipitation

  3. Editorial: Reviewer Selection Process and New Areas of Expertise in GEMS

    Science.gov (United States)

    Liemohn, Michael W.; Balikhin, Michael; Kepko, Larry; Rodger, Alan; Wang, Yuming

    2016-01-01

    One method of selecting potential reviewers for papers submitted to the Journal of Geophysical Research Space Physics is to filter the user database within the Geophysical Electronic Manuscript System (GEMS) by areas of expertise. The list of these areas in GEMS can be self selected by users in their profile settings. The Editors have added 18 new entries to this list, an increase of 33 more than the previous 55 entries. All space physicists are strongly encouraged to update their profile settings in GEMS, especially their areas of expertise selections, and details of how to do this are provided.

  4. GEM scintillation readout with avalanche photodiodes

    CERN Document Server

    Conceição, A S; Fernandes, L M P; Monteiro, C M B; Coelho, L C C; Azevedo, C D R; Veloso, J F C A; Lopesac, J A M; dos Santosa, J M F

    2007-01-01

    The use of the scintillation produced in the charge avalanches in GEM holes as signal amplification and readout is investigated for xenon. A VUV-sensitive avalanche photodiode has been used as photosensor. Detector gains of about 4 × 104 are achieved in scintillation readout mode, for GEM voltages of 490 V and for a photosensor gain of 150. Those gains are more than one order of magnitude larger than what is obtained using charge readout. In addition, the energy resolutions achieved with the scintillation readout are lower than those achieved with charge readout. The GEM scintillation yield in xenon was measured as a function of GEM voltage, presenting values that are about a half of those achieved for the charge yield, and reach about 730 photons per primary electron at GEM voltages of 490 V.

  5. Ground Enterprise Management System, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Emergent Space Technologies Inc. proposes to develop the Ground Enterprise Management System (GEMS) for spacecraft ground systems. GEMS will provide situational...

  6. The germanium wall of the GEM detector system GEM Collaboration

    International Nuclear Information System (INIS)

    Betigeri, M.; Biakowski, E.; Bojowald, H.; Budzanowski, A.; Chatterjee, A.; Drochner, M.; Ernst, J.; Foertsch, S.; Freindl, L.; Frekers, D.; Garske, W.; Grewer, K.; Hamacher, A.; Igel, S.; Ilieva, J.; Jarczyk, L.; Jochmann, M.; Kemmerling, G.; Kilian, K.; Kliczewski, S.; Klimala, W.; Kolev, D.; Kutsarova, T.; Lieb, J.; Lippert, G.; Machner, H.; Magiera, A.; Nann, H.; Pentchev, L.; Plendl, H.S.; Protic, D.; Razen, B.; Rossen, P. von; Roy, B.J.; Siudak, R.; Smyrski, J.; Srikantiah, R.V.; Strzakowski, A.; Tsenov, R.; Zolnierczuk, P.A.; Zwoll, K.

    1999-01-01

    A stack of annular detectors made of high-purity germanium was developed. The detectors are position sensitive with radial structures. The first one ('Quirl') is double-sided position sensitive defining 40,000 pixels, the following three (E1, E2 and E3) have 32 wedges each. The Quirl acts as tracker while the other three act as calorimeter. The stack was successfully operated in meson production reactions close to threshold

  7. Analysis of current situation of information disclosure of listed companies on GEM

    Directory of Open Access Journals (Sweden)

    Zhirong Shen

    2017-03-01

    Full Text Available In the afternoon on October 23th, 2009, GEM was officially launched in our country. Due to the lack of experience in the market supervision, information disclosure violations frequently occurred. In April 2015, Shenzhen Stock Exchange puts forward morning information disclosure system to strengthen the reform of information disclosure system. Therefore, this paper deeply focuses on the current situation of information disclosure violations on GEM for the purpose of attracting more attention to the problems. Through studying the information disclosure violations of the listed companies on GEM from 2011 to September 30th, 2015, this paper divides the violations into the following four types: false record, misleading statement, material misstatement and delayed disclosure. On the other hand, we find that these types of violations are concurrent. From this discussion, we may safely draw the conclusion that the information disclosure of listed companies on GEM has the problem of untruthfulness, incorrectness, incompleteness and delay.

  8. Development of a Diehard GEM using PTFE insulator substrate

    OpenAIRE

    Wakabayashi, M.; Komiya, K.; Tamagawa, T.; Takeuchi, Y.; Aoki, K.; Taketani, A.; Hamagaki, H.

    2014-01-01

    We have developed the gas electron multiplier (GEM) using polytetrafluoroethylene (PTFE) insulator substrate (PTFE-GEM). Carbonization on insulator layer by discharges shorts the GEM electrodes, causing permanent breakdown. Since PTFE is hard to be carbonized against arc discharges, PTFE-GEM is expected to be robust against breakdown. Gains as high as 2.6x10^4 were achieved with PTFE-GEM (50 um thick) in Ar/CO2 = 70%/30% gas mixture at V_GEM = 730V. PTFE-GEM never showed a permanent breakdown...

  9. Fast drift CRID with GEM

    CERN Document Server

    Vavra, J; McCulloch, M; Stiles, P; Sauli, Fabio

    1999-01-01

    The only available technique at the present time, to perform particle identification up to 40-50 GeV/c in a 4 pi solenoidal geometry using the Cherenkov ring imaging method is the use of gaseous detectors filled with either TMAE or TEA photocathodes, and a combination of the gaseous, and solid or liquid radiators. If one would consider building such a device, one may want to investigate alternative methods of building a single-electron detector. This paper investigates the feasibility of using the GEM together with a simple MWPC detector employing 33 mu m diameter carbon wires to obtain a second coordinate. The results are compared to the CRID single-electron detector.

  10. The GEM code. A simulation program for the evaporation and the fission process of an excited nucleus

    Energy Technology Data Exchange (ETDEWEB)

    Furihata, Shiori [Mitsubishi Research Institute Inc., Tokyo (Japan); Niita, Koji [Research Organization for Information Science and Technology, Tokai, Ibaraki (Japan); Meigo, Shin-ichiro; Ikeda, Yujiro; Maekawa, Fujio [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    2001-03-01

    The GEM code is a simulation program which describes the de-excitation process of an excited nucleus, which is based on the Generalized Evaporation Model and the Atchison fission model. It has been shown that the combination of the Bertini intranuclear cascade model and GEM accurately predicts the cross sections of light fragments, such as Be produced from the proton-induced reactions. It has also been shown that the use of the reevaluated parameters in the Atchison model improves predictions of cross sections of fission fragments produced from the proton-induced reaction on Au. In this report, we present details and the usage of the GEM code. Furthermore, the results of benchmark calculations are shown by using the combination of the Bertini intranuclear cascade model and the GEM code (INC/GEM). Neutron spectra and isotope production cross sections from the reactions on various targets irradiated by protons are calculated with INC/GEM. Those results are compared with experimental data as well as the calculation results with LAHET. INC/GEM reproduces the experiments of double differential neutron emissions from the reaction on Al and Pb. The isotopic distributions for He, Li, and Be produced from the reaction on Ag are in good agreement with experimental data within 50%, although INC/GEM underestimates those of heavier nuclei than O. It is also shown that the predictions with INC/GEM for isotope production of light fragments, such as Li and Be, are better than those calculation with LAHET, particularly for heavy target. INC/GEM also gives better estimates of the cross sections of fission products than LAHET. (author)

  11. Characterization of a hybrid GEM-Micromegas detector with respect to its application in a continuously read out TPC

    Science.gov (United States)

    Ratza, Viktor; Ball, Markus; Liebtrau, M.; Ketzer, Bernhard

    2018-02-01

    In the context of the upgrade of the LHC during the second long shutdown the interaction rate of the ALICE experiment will be increased up to 50 kHz for Pb-Pb collisions. As a consequence, a continuous read-out of the Time Projection Chamber (TPC) will be required. To keep the space-charge distortions at a manageable size, the ion backflow of the charge amplification system has to be significantly reduced. At the same time an excellent detector performance and stability of the system has to be maintained. A solution with four Gaseous Electron Multipliers (GEMs) has been adopted as baseline solution for the upgraded chambers. As an alternative approach a hybrid GEM-Micromegas detector consisting of one Micromegas (MM) and two GEMs has been investigated. The recent results of the study of the hybrid GEM-Micromegas detector will be presented and compared to measurements with four GEM foils.

  12. The gain in Thick GEM multipliers and its time-evolution

    CERN Document Server

    Alexeev, M; Bradamante, F; Bressan, A; Buechele, M; Chiosso, M; Ciliberti, P; Dalla Torre, S; Dasgupta, S; Denisov, O; Duic, V; Finger, M; Finger Jr, M; Fischer, H; Gobbo, B; Gregori, M; Herrmann, F; Koenigsmann, K; Levorato, S; Maggiora, A; Makke, N; Martin, A; Menon, G; Novakova, K; Novy, J; Panzieri, D; Pereira, F A; Santos, C A; Sbrizzai, G; Schiavon, P; Schopferer, S; Slunecka, M; Sozzi, F; Steiger, L; Sulc, M; Takekawa, S; Tessarotto, F; Veloso, J F C A

    2016-01-01

    In the context of a project to upgrade the gas photon detectors of COMPASS RICH-1, we have performed an R&D programme aimed to develop photon detectors based on multi-layer arrangements of thick GEM electron multipliers coupled to a CsI photoconverter. For this purpose, thick GEMs have been characterised in detail including the gain performance, its dependance on the geometrical parameters and its time-evolution, a feature exhibited by the gas detectors with open insulator surfaces. The variation due to this evolution drammatically depends on the parameters themselves. In the present article we summarise the outcomes of the studies dedicated to the thick GEM gain and its evolution versus time. We also include a qualitative model which accounts for the peculiar details of the observed thick GEM gain time-evolution.

  13. Quality control for the first large areas of triple GEM chambers for the CMS endcaps

    CERN Document Server

    Tytgat, Michael

    2015-01-01

    The CMS GEM collaboration plans to equip the very forward muon system with triple GEM detectors that can withstand the environment of the high-luminosity LHC. This project is at the final stages of R and D and moving to production. An unprecedented large area of several 100m2 are to be instrumented with GEM detectors which will be produced in six different sites around the world. A common construction and quality control procedure is required to ensure the performance of each detector. The quality control steps will include optical inspection, cleaning and baking of all materials and parts used to build the detector, leakage current tests of the GEM foils, high voltage tests, gas leak tests of the chambers and monitoring pressure drop vs. time, gain calibration to know the optimal operation region of the detector, gain uniformity tests, and studying the efficiency, noise and tracking performance of the detectors in a cosmic stand using scintillators.

  14. First Year K-12 Teachers as High Leverage Point to Implement GEMS Space Science Curriculum Sequence

    Science.gov (United States)

    Slater, Timothy F.; Mendez, B. J.; Schultz, G.; Wierman, T.

    2013-01-01

    The recurring challenge for curriculum developers is how to efficiently prepare K-12 classroom teachers to use new curricula. First-year teachers, numbering nearly 250,000 in the US each year, have the greatest potential to impact the largest number of students because they have potential to be in the classroom for thirty years. At the same time, these novice teachers are often the most open minded about adopting curricular innovation because they are not yet deeply entrenched in existing practices. To take advantage of this high leverage point, a collaborative of space scientists and science educators at the University of California, Berkeley’s Lawrence Hall of Science and Center for Science Education at the Space Sciences Laboratory with experts from the Astronomical Society of the Pacific, the University of Wyoming, and the CAPER Center for Astronomy & Physics Education experimented with a unique professional development model focused on helping master teachers work closely with pre-service teachers during their student teaching internship field experience. The Advancing Mentor and Novice Teachers in Space Science (AMANTISS) team first identified master teachers who supervise novice, student teachers and trained these master teachers to use the GEMS Space Science Curriculum Sequence. Then, these master teachers were mentored in coaching interning student teachers assigned to them in using GEMS materials. Evaluation showed that novice teachers mentored by the master teachers felt knowledgeable after teaching the GEMS units. However, they seemed relatively less confident about the solar system and objects beyond the solar system. Overall, mentees felt strongly at the end of the year that they have acquired good strategies for teaching the various topics, suggesting that the support they received while teaching and working with a mentor was of real benefit to them. Funding provided in part by NASA ROSES AMANTISS NNX09AD51G

  15. What controls the vertical distribution of aerosol? Relationships between process sensitivity in HadGEM3–UKCA and inter-model variation from AeroCom Phase II

    Directory of Open Access Journals (Sweden)

    Z. Kipling

    2016-02-01

    Full Text Available The vertical profile of aerosol is important for its radiative effects, but weakly constrained by observations on the global scale, and highly variable among different models. To investigate the controlling factors in one particular model, we investigate the effects of individual processes in HadGEM3–UKCA and compare the resulting diversity of aerosol vertical profiles with the inter-model diversity from the AeroCom Phase II control experiment. In this way we show that (in this model at least the vertical profile is controlled by a relatively small number of processes, although these vary among aerosol components and particle sizes. We also show that sufficiently coarse variations in these processes can produce a similar diversity to that among different models in terms of the global-mean profile and, to a lesser extent, the zonal-mean vertical position. However, there are features of certain models' profiles that cannot be reproduced, suggesting the influence of further structural differences between models. In HadGEM3–UKCA, convective transport is found to be very important in controlling the vertical profile of all aerosol components by mass. In-cloud scavenging is very important for all except mineral dust. Growth by condensation is important for sulfate and carbonaceous aerosol (along with aqueous oxidation for the former and ageing by soluble material for the latter. The vertical extent of biomass-burning emissions into the free troposphere is also important for the profile of carbonaceous aerosol. Boundary-layer mixing plays a dominant role for sea salt and mineral dust, which are emitted only from the surface. Dry deposition and below-cloud scavenging are important for the profile of mineral dust only. In this model, the microphysical processes of nucleation, condensation and coagulation dominate the vertical profile of the smallest particles by number (e.g. total CN  >  3 nm, while the profiles of larger particles (e.g. CN

  16. Europa Imaging Highlights during GEM

    Science.gov (United States)

    1998-01-01

    During the two year Galileo Europa Mission (GEM), NASA's Galileo spacecraft will focus intensively on Jupiter's intriguing moon, Europa. This montage shows samples of some of the features that will be imaged during eight successive orbits. The images in this montage are in order of increasing orbit from the upper left (orbit 11) to the lower right (orbit 19).DESCRIPTIONS AND APPROXIMATE RESOLUTIONSTriple bands and dark spots1.6 kilometers/pixelConamara Chaos1.6 kilometers/pixelMannan'an Crater1.6 kilometers/ pixelCilix1.6 kilometers/pixelAgenor Linea and Thrace Macula2 kilometers/pixelSouth polar terrain2 kilometers/pixelRhadamanthys Linea1.6 kilometers/pixelEuropa plume search7 kilometers/pixel1. Triple bands and dark spots were the focus of some images from Galileo's eleventh orbit of Jupiter. Triple bands are multiple ridges with dark deposits along the outer margins. Some extend for thousands of kilometers across Europa's icy surface. They are cracks in the ice sheet and indicate the great stresses imposed on Europa by tides raised by Jupiter, as well as Europa's neighboring moons, Ganymede and Io. The dark spots or 'lenticulae' are spots of localized disruption.2. The Conamara Chaos region reveals icy plates which have broken up, moved, and rafted into new positions. This terrain suggests that liquid water or ductile ice was present near the surface. On Galileo's twelfth orbit of Jupiter, sections of this region with resolutions as high as 10 meters per picture element will be obtained.3. Mannann'an Crater is a feature newly discovered by Galileo in June 1996. Color and high resolution images (to 40 meters per picture element) from Galileo's fourteenth orbit of Jupiter will offer a close look at the crater and help characterize how impacts affect the icy surface of this moon.4. Cilix, a large mound about 1.5 kilometers high, is the center of Europa's coordinate system. Its concave top and what may be flow like features to the southwest of the mound are

  17. Geostationary Environment Monitoring Spectrometer (gems) Over the Korea Peninsula and Asia-Pacific Region

    Science.gov (United States)

    Lasnik, J.; Stephens, M.; Baker, B.; Randall, C.; Ko, D. H.; Kim, S.; Kim, Y.; Lee, E. S.; Chang, S.; Park, J. M.; SEO, S. B.; Youk, Y.; Kong, J. P.; Lee, D.; Lee, S. H.; Kim, J.

    2014-12-01

    Introduction: The Geostationary Environment Monitoring Spectrometer (GEMS) is one of two instruments manifested aboard the South Korean Geostationary Earth Orbit KOrea Multi-Purpose SATellite-2B (GEO-KOMPSAT-2B or GK2B), which is scheduled to launch in 2018. Jointly developed/built by KARI and Ball Aerospace, GEMS is a geostationary UV-Vis hyperspectral imager designed to monitor trans-boundary tropospheric pollution events over the Korean peninsula and Asia-Pacific region. The spectrometer provides high temporal and spatial resolution (3.5 km N/S by 7.2 km E/W) measurements of ozone, its precursors, and aerosols. Over the short-term, hourly measurements by GEMS will improve early warnings for potentially dangerous pollution events and monitor population exposure. Over the 10-year mission-life, GEMS will serve to enhance our understanding of long-term climate change and broader air quality issues on both a regional and global scale. The GEMS sensor design and performance are discussed, which includes an overview of measurement capabilities and the on-orbit concept of operations. GEMS Sensor Overview: The GEMS hyperspectral imaging system consists of a telescope and Offner grating spectrometer that feeds a single CCD detector array. A spectral range of 300-500 nm and sampling of 0.2 nm enables NO2, SO2, HCHO, O3, and aerosol retrieval. The GEMS field of regard (FOR), which extends from 5°S to 45°N in latitude and 75°E to 145°E in longitude, is operationally achieved using an onboard two-axis scan mirror. On-orbit, the radiometric calibration is maintained using solar measurements, which are performed using two onboard diffusers: a working diffuser that is deployed routinely for the purpose of solar calibration, and a reference diffuser that is deployed sparingly for the purpose of monitoring working diffuser performance degradation.

  18. Development of a Diehard GEM using PTFE insulator substrate

    International Nuclear Information System (INIS)

    Wakabayashi, M; Tamagawa, T; Takeuchi, Y; Aoki, K; Taketani, A; Komiya, K; Hamagaki, H

    2014-01-01

    We have developed the gas electron multiplier (GEM) using polytetrafluoroethylene (PTFE) insulator substrate (PTFE-GEM). Carbonization on insulator layer by discharges shorts the GEM electrodes, causing permanent breakdown. Since PTFE is hard to be carbonized against arc discharges, PTFE-GEM is expected to be robust against breakdown. Gains as high as 2.6 × 10 4 were achieved with PTFE-GEM (50 μm thick) in Ar/CO 2 = 70%/30% gas mixture at V GEM = 730 V. PTFE-GEM never showed a permanent breakdown even after suffering more than 40000 times discharges during the experiment. The result demonstrates that PTFE-GEM is really robust against discharges. We conclude that PTFE is an excellent insulator material for the GEM productions

  19. Evaluation of ozone profile and tropospheric ozone retrievals from GEMS and OMI spectra

    Directory of Open Access Journals (Sweden)

    J. Bak

    2013-02-01

    Full Text Available South Korea is planning to launch the GEMS (Geostationary Environment Monitoring Spectrometer instrument into the GeoKOMPSAT (Geostationary Korea Multi-Purpose SATellite platform in 2018 to monitor tropospheric air pollutants on an hourly basis over East Asia. GEMS will measure backscattered UV radiances covering the 300–500 nm wavelength range with a spectral resolution of 0.6 nm. The main objective of this study is to evaluate ozone profiles and stratospheric column ozone amounts retrieved from simulated GEMS measurements. Ozone Monitoring Instrument (OMI Level 1B radiances, which have the spectral range 270–500 nm at spectral resolution of 0.42–0.63 nm, are used to simulate the GEMS radiances. An optimal estimation-based ozone profile algorithm is used to retrieve ozone profiles from simulated GEMS radiances. Firstly, we compare the retrieval characteristics (including averaging kernels, degrees of freedom for signal, and retrieval error derived from the 270–330 nm (OMI and 300–330 nm (GEMS wavelength ranges. This comparison shows that the effect of not using measurements below 300 nm on retrieval characteristics in the troposphere is insignificant. However, the stratospheric ozone information in terms of DFS decreases greatly from OMI to GEMS, by a factor of ∼2. The number of the independent pieces of information available from GEMS measurements is estimated to 3 on average in the stratosphere, with associated retrieval errors of ~1% in stratospheric column ozone. The difference between OMI and GEMS retrieval characteristics is apparent for retrieving ozone layers above ~20 km, with a reduction in the sensitivity and an increase in the retrieval errors for GEMS. We further investigate whether GEMS can resolve the stratospheric ozone variation observed from high vertical resolution Earth Observing System (EOS Microwave Limb Sounder (MLS. The differences in stratospheric ozone profiles between GEMS and MLS are comparable to those

  20. COTHERM: Modelling fluid-rock interactions in Icelandic geothermal systems

    Science.gov (United States)

    Thien, Bruno; Kosakowski, Georg; Kulik, Dmitrii

    2014-05-01

    Mineralogical alteration of reservoir rocks, driven by fluid circulation in natural or enhanced geothermal systems, is likely to influence the long-term performance of geothermal power generation. A key factor is the change of porosity due to dissolution of primary minerals and precipitation of secondary phases. Porosity changes will affect fluid circulation and solute transport, which, in turn, influence mineralogical alteration. This study is part of the Sinergia COTHERM project (COmbined hydrological, geochemical and geophysical modeling of geotTHERMal systems) that is an integrative research project aimed at improving our understanding of the sub-surface processes in magmatically-driven natural geothermal systems. We model the mineralogical and porosity evolution of Icelandic geothermal systems with 1D and 2D reactive transport models. These geothermal systems are typically high enthalphy systems where a magmatic pluton is located at a few kilometers depth. The shallow plutons increase the geothermal gradient and trigger the circulation of hydrothermal waters with a steam cap forming at shallow depth. We investigate two contrasting geothermal systems: Krafla, for which the water recharge consists of meteoritic water; and Reykjanes, for which the water recharge mainly consists of seawater. The initial rock composition is a fresh basalt. We use the GEM-Selektor geochemical modeling package [1] for calculation of kinetically controlled mineral equilibria between the rock and the ingression water. We consider basalt minerals dissolution kinetics according to Palandri & Kharaka [2]. Reactive surface areas are assumed to be geometric surface areas, and are corrected using a spherical-particle surface/mass relationship. For secondary minerals, we consider the partial equilibrium assuming that the primary mineral dissolution is slow, and the secondary mineral precipitation is fast. Comparison of our modeling results with the mineralogical assemblages observed in the

  1. Systems analysis programs for hands-on integrated reliability evaluations (SAPHIRE), Version 5.0

    International Nuclear Information System (INIS)

    Russell, K.D.; Kvarfordt, K.J.; Hoffman, C.L.

    1995-10-01

    The Systems Analysis Programs for Hands-on Integrated Reliability Evaluations (SAPHIRE) refers to a set of several microcomputer programs that were developed to create and analyze probabilistic risk assessments (PRAs), primarily for nuclear power plants. The Graphical Evaluation Module (GEM) is a special application tool designed for evaluation of operational occurrences using the Accident Sequence Precursor (ASP) program methods. GEM provides the capability for an analyst to quickly and easily perform conditional core damage probability (CCDP) calculations. The analyst can then use the CCDP calculations to determine if the occurrence of an initiating event or a condition adversely impacts safety. It uses models and data developed in the SAPHIRE specially for the ASP program. GEM requires more data than that normally provided in SAPHIRE and will not perform properly with other models or data bases. This is the first release of GEM and the developers of GEM welcome user comments and feedback that will generate ideas for improvements to future versions. GEM is designated as version 5.0 to track GEM codes along with the other SAPHIRE codes as the GEM relies on the same, shared database structure

  2. Genome-scale modeling of human metabolism - a systems biology approach.

    Science.gov (United States)

    Mardinoglu, Adil; Gatto, Francesco; Nielsen, Jens

    2013-09-01

    Altered metabolism is linked to the appearance of various human diseases and a better understanding of disease-associated metabolic changes may lead to the identification of novel prognostic biomarkers and the development of new therapies. Genome-scale metabolic models (GEMs) have been employed for studying human metabolism in a systematic manner, as well as for understanding complex human diseases. In the past decade, such metabolic models - one of the fundamental aspects of systems biology - have started contributing to the understanding of the mechanistic relationship between genotype and phenotype. In this review, we focus on the construction of the Human Metabolic Reaction database, the generation of healthy cell type- and cancer-specific GEMs using different procedures, and the potential applications of these developments in the study of human metabolism and in the identification of metabolic changes associated with various disorders. We further examine how in silico genome-scale reconstructions can be employed to simulate metabolic flux distributions and how high-throughput omics data can be analyzed in a context-dependent fashion. Insights yielded from this mechanistic modeling approach can be used for identifying new therapeutic agents and drug targets as well as for the discovery of novel biomarkers. Finally, recent advancements in genome-scale modeling and the future challenge of developing a model of whole-body metabolism are presented. The emergent contribution of GEMs to personalized and translational medicine is also discussed. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. GEM applications outside high energy physics

    CERN Document Server

    Duarte Pinto, Serge

    2013-01-01

    From its invention in 1997, the Gas Electron Multiplier has been applied in nuclear and high energy physics experiments. Over time however, other applications have also exploited the favorable properties of GEMs. The use of GEMs in these applications will be explained in principle and practice. This paper reviews applications in research, beam instrumentation and homeland security. The detectors described measure neutral radiations such as photons, x-rays, gamma rays and neutrons, as well as all kinds of charged radiation. This paper provides an overview of the still expanding range of possibilities of this versatile detector concept.

  4. Measurement of Z boson production in association with jets at the LHC and study of a DAQ system for the Triple-GEM detector in view of the CMS upgrade

    CERN Document Server

    Léonard, Alexandre

    This PhD thesis presents the measurement of the differential cross section for the production of a Z boson in association with jets in proton-proton collisions taking place at the Large Hadron Collider (LHC) at CERN, at a centre-of-mass energy of 8 TeV. A development of a data acquisition (DAQ) system for the Triple-Gas Electron Multiplier (GEM) detector in view of the Compact Muon Solenoid (CMS) detector upgrade is also presented. The events used for the data analysis were collected by the CMS detector during the year 2012 and constitute a sample of 19.6/fb of integrated luminosity. The cross section measurements are performed as a function of the jet multiplicity, the jet transverse momentum and pseudorapidity, and the scalar sum of the jet transverse momenta. The results were obtained by correcting the observed distributions for detector effects. The measured differential cross sections are compared to some state of the art Monte Carlo predictions MadGraph 5, Sherpa 2 and MadGraph5_aMC@NLO. These measureme...

  5. A process-based evaluation of dust-emitting winds in the CMIP5 simulation of HadGEM2-ES

    Science.gov (United States)

    Fiedler, Stephanie; Knippertz, Peter; Woodward, Stephanie; Martin, Gill M.; Bellouin, Nicolas; Ross, Andrew N.; Heinold, Bernd; Schepanski, Kerstin; Birch, Cathryn E.; Tegen, Ina

    2016-02-01

    Despite the importance of dust aerosol in the Earth system, state-of-the-art models show a large variety for North African dust emission. This study presents a systematic evaluation of dust emitting-winds in 30 years of the historical model simulation with the UK Met Office Earth-system model HadGEM2-ES for the Coupled Model Intercomparison Project Phase 5. Isolating the effect of winds on dust emission and using an automated detection for nocturnal low-level jets (NLLJs) allow an in-depth evaluation of the model performance for dust emission from a meteorological perspective. The findings highlight that NLLJs are a key driver for dust emission in HadGEM2-ES in terms of occurrence frequency and strength. The annually and spatially averaged occurrence frequency of NLLJs is similar in HadGEM2-ES and ERA-Interim from the European Centre for Medium-Range Weather Forecasts. Compared to ERA-Interim, a stronger pressure ridge over northern Africa in winter and the southward displaced heat low in summer result in differences in location and strength of NLLJs. Particularly the larger geostrophic winds associated with the stronger ridge have a strengthening effect on NLLJs over parts of West Africa in winter. Stronger NLLJs in summer may rather result from an artificially increased mixing coefficient under stable stratification that is weaker in HadGEM2-ES. NLLJs in the Bodélé Depression are affected by stronger synoptic-scale pressure gradients in HadGEM2-ES. Wintertime geostrophic winds can even be so strong that the associated vertical wind shear prevents the formation of NLLJs. These results call for further model improvements in the synoptic-scale dynamics and the physical parametrization of the nocturnal stable boundary layer to better represent dust-emitting processes in the atmospheric model. The new approach could be used for identifying systematic behavior in other models with respect to meteorological processes for dust emission. This would help to improve dust

  6. Development of GEMs at Hampton University

    Science.gov (United States)

    Liyanage, Anusha; Kohl, Michael; MUSE Collaboration

    2015-10-01

    Two GEM telescopes each consisting of three 10×10 cm2 triple-GEM chambers 30-40 cm apart were built, tested and operated by the Hampton group. They are read out with APV25 frontend chips and FPGA based digitizing electronics developed by INFN Rome. The telescopes served as luminosity monitors for the OLYMPUS experiment at DESY in Hamburg, Germany, with positron and electron beams at 2 GeV. The telescopes have been recycled to serve as the beam particle tracker of the MUSE experiment at the Paul Scherrer Institute in Switzerland. In the identical configuration as in OLYMPUS, the telescope was limiting the accepted trigger rate in the test measurements. Therefore, an effort is ongoing to improve the GEM readout speed to meet the trigger rate at the design intensity of the MUSE experiment. Further, the Hampton group is responsible for the DarkLight phase-I lepton tracker which is in preparation at the low energy-recovering facility (LERF) at the Thomas Jefferson National Accelerator Facility in Newport News, USA, sponsored by the National Science Foundation through a Major Research Instrumentation (MRI) grant. The group's activities on GEM detector development will be summarized, and the achieved performance and the current effort to further improvements will be discussed.

  7. 3D simulation of electron and ion transmission of GEM-based detectors

    Science.gov (United States)

    Bhattacharya, Purba; Mohanty, Bedangadas; Mukhopadhyay, Supratik; Majumdar, Nayana; da Luz, Hugo Natal

    2017-10-01

    Time Projection Chamber (TPC) has been chosen as the main tracking system in several high-flux and high repetition rate experiments. These include on-going experiments such as ALICE and future experiments such as PANDA at FAIR and ILC. Different R&D activities were carried out on the adoption of Gas Electron Multiplier (GEM) as the gas amplification stage of the ALICE-TPC upgrade version. The requirement of low ion feedback has been established through these activities. Low ion feedback minimizes distortions due to space charge and maintains the necessary values of detector gain and energy resolution. In the present work, Garfield simulation framework has been used to study the related physical processes occurring within single, triple and quadruple GEM detectors. Ion backflow and electron transmission of quadruple GEMs, made up of foils with different hole pitch under different electromagnetic field configurations (the projected solutions for the ALICE TPC) have been studied. Finally a new triple GEM detector configuration with low ion backflow fraction and good electron transmission properties has been proposed as a simpler GEM-based alternative suitable for TPCs for future collider experiments.

  8. Inter-comparison of MAX-DOAS Retrieved Vertical Profiles of Aerosol Extinction, SO2 and NO2 in the Alberta Oil Sands with LIDAR Data and GEM-MACH Air Quality Model.

    Science.gov (United States)

    Davis, Zoe; Friess, Udo; Strawbridge, Kevin; Whiteway, James; Aggarwal, Monika; Makar, Paul; Li, Shao-Meng; O'Brien, Jason; Baray, Sabour; Schnitzler, Elijah; Olfert, Jason S.; Osthoff, Hans D.; Lobo, Akshay; McLaren, Robert

    2016-04-01

    Understanding industrial emissions of trace gas pollutants in the Alberta oil sands is essential to maintaining air quality standards and informing public policy. Multi-Axis Differential Optical Absorption Spectroscopy (MAX-DOAS) measurements of trace gases can improve knowledge of pollutant levels, vertical distribution and chemical transformation. During an intensive air measurement campaign to study emissions, transport, transformation and deposition of oil sands air pollutants from August to September of 2013, a MAX-DOAS instrument was deployed at a site north of Fort McMurray, Alberta to determine the vertical profiles of aerosol extinction, NO2 and SO2 through retrieval from the MAX-DOAS spectral measurements using an optimal estimation method. The large complement of data collected from multiple instruments deployed during this field campaign provides a unique opportunity to validate and characterize the performance of the MAX-DOAS vertical profile retrievals. Aerosol extinction profiles determined from two Light Detection and Ranging (LIDAR) instruments, one collocated and the other on a Twin Otter aircraft that flew over the site during the study, will be compared to the MAX-DOAS aerosol extinction profile retrievals. Vertical profiles of NO2 and SO2 retrieved from the MAX-DOAS measurements will be further compared with the composite vertical profiles measured from the flights of a second aircraft, the NRC-Convair 580, over the field site during the same measurement period. Finally, the MAX-DOAS retrieved tropospheric vertical column densities (VCDs) of SO2 and NO2 will be compared to the predicted VCDs from Environment and Climate Change Canada's Global Environmental Multi-scale - Modelling Air quality and Chemistry (GEM-MACH) air quality model over the grid cell containing the field site. Emission estimates of SO2 from the major oil mining facility Syncrude Mildred Lake using the MAX-DOAS VCD results, validated through the detailed characterization above

  9. Quality control for the first large areas of triple-GEM chambers for the CMS endcaps

    Science.gov (United States)

    Abbaneo, D.; Abbas, M.; Abbrescia, M.; Abi Akl, M.; Aboamer, O.; Acosta, D.; Ahmad, A.; Ahmed, W.; Aleksandrov, A.; Altieri, P.; Asawatangtrakuldee, C.; Aspell, P.; Assran, Y.; Awan, I.; Bally, S.; Ban, Y.; Banerjee, S.; Barashko, V.; Barria, P.; Bencze, G.; Beni, N.; Benussi, L.; Bhopatkar, V.; Bianco, S.; Bos, J.; Bouhali, O.; Braghieri, A.; Braibant, S.; Buontempo, S.; Calabria, C.; Caponero, M.; Caputo, C.; Cassese, F.; Castaneda, A.; Cauwenbergh, S.; Cavallo, F. R.; Celik, A.; Choi, M.; Choi, S.; Christiansen, J.; Cimmino, A.; Colafranceschi, S.; Colaleo, A.; Conde Garcia, A.; Czellar, S.; Dabrowski, M. M.; De Lentdecker, G.; De Oliveira, R.; de Robertis, G.; Dildick, S.; Dorney, B.; Endroczi, G.; Errico, F.; Fenyvesi, A.; Ferry, S.; Furic, I.; Giacomelli, P.; Gilmore, J.; Golovtsov, V.; Guiducci, L.; Guilloux, F.; Gutierrez, A.; Hadjiiska, R. M.; Hauser, J.; Hoepfner, K.; Hohlmann, M.; Hoorani, H.; Iaydjiev, P.; Jeng, Y. G.; Kamon, T.; Karchin, P.; Korytov, A.; Krutelyov, S.; Kumar, A.; Kim, H.; Lee, J.; Lenzi, T.; Litov, L.; Loddo, F.; Madorsky, A.; Maerschalk, T.; Maggi, M.; Magnani, A.; Mal, P. K.; Mandal, K.; Marchioro, A.; Marinov, A.; Majumdar, N.; Merlin, J. A.; Mitselmakher, G.; Mohanty, A. K.; Mohapatra, A.; Molnar, J.; Muhammad, S.; Mukhopadhyay, S.; Naimuddin, M.; Nuzzo, S.; Oliveri, E.; Pant, L. M.; Paolucci, P.; Park, I.; Passeggio, G.; Pavlov, B.; Philipps, B.; Piccolo, D.; Postema, H.; Puig Baranac, A.; Radi, A.; Radogna, R.; Raffone, G.; Ranieri, A.; Rashevski, G.; Riccardi, C.; Rodozov, M.; Rodrigues, A.; Ropelewski, L.; RoyChowdhury, S.; Ryu, G.; Ryu, M. S.; Safonov, A.; Salva, S.; Saviano, G.; Sharma, A.; Sharma, A.; Sharma, R.; Shah, A. H.; Shopova, M.; Sturdy, J.; Sultanov, G.; Swain, S. K.; Szillasi, Z.; Talvitie, J.; Tatarinov, A.; Tuuva, T.; Tytgat, M.; Vai, I.; Van Stenis, M.; Venditti, R.; Verhagen, E.; Verwilligen, P.; Vitulo, P.; Volkov, S.; Vorobyev, A.; Wang, D.; Wang, M.; Yang, U.; Yang, Y.; Yonamine, R.; Zaganidis, N.; Zenoni, F.; Zhang, A.

    2018-02-01

    The CMS Collaboration plans to equip the very forward muon system with triple-GEM detectors that can withstand the environment of the High-Luminosity LHC. This project is at the final stages of R&D and moving to production. An unprecedented large area of several 100 m2 are to be instrumented with GEM detectors which will be produced in six different sites around the world. A common construction and quality control procedure is required to ensure the performance of each detector. The quality control steps will include optical inspection, cleaning and baking of all materials and parts used to build the detector, leakage current tests of the GEM foils, high voltage tests, gas leak tests of the chambers and monitoring pressure drop vs. time, gain calibration to know the optimal operation region of the detector, gain uniformity tests, and studying the efficiency, noise and tracking performance of the detectors in a cosmic stand using scintillators.

  10. Quality control for the first large areas of triple-GEM chambers for the CMS endcaps

    CERN Document Server

    AUTHOR|(CDS)2068936; Abbas, M.; Abbrescia, M.; Abi Akl, M.; Aboamer, O.; Acosta, D.; Ahmad, A.; Ahmed, W.; Aleksandrov, A.; Altieri, P.; Asawatangtrakuldee, C.; Aspell, P.; Assran, Y.; Awan, I.; Bally, S.; Ban, Y.; Banerjee, S.; Barashko, V.; Barria, P.; Bencze, G.; Beni, N.; Benussi, L.; Bhopatkar, V.; Bianco, S.; Bos, J.; Bouhali, O.; Braghieri, A.; Braibant, S.; Buontempo, S.; Calabria, C.; Caponero, M.; Caputo, C.; Cassese, F.; Castaneda, A.; Cauwenbergh, S.; Cavallo, F.R.; Celik, A.; Choi, M.; Choi, S.; Christiansen, J.; Cimmino, A.; Colafranceschi, S.; Colaleo, A.; Conde Garcia, A.; Czellar, S.; Dabrowski, M.M.; De Lentdecker, G.; De Oliveira, R.; de Robertis, G.; Dildick, S.; Dorney, B.; Endroczi, G.; Errico, F.; Fenyvesi, A.; Ferry, S.; Furic, I.; Giacomelli, P.; Gilmore, J.; Golovtsov, V.; Guiducci, L.; Guilloux, F.; Gutierrez, A.; Hadjiiska, R.M.; Hauser, J.; Hoepfner, K.; Hohlmann, M.; Hoorani, H.; Iaydjiev, P.; Jeng, Y.G.; Kamon, T.; Karchin, P.; Korytov, A.; Krutelyov, S.; Kumar, A.; Kim, H.; Lee, J.; Lenzi, T.; Litov, L.; Loddo, F.; Madorsky, A.; Maerschalk, T.; Maggi, M.; Magnani, A.; Mal, P.K.; Mandal, K.; Marchioro, A.; Marinov, A.; Majumdar, N.; Merlin, J.A.; Mitselmakher, G.; Mohanty, A.K.; Mohapatra, A.; Molnar, J.; Muhammad, S.; Mukhopadhyay, S.; Naimuddin, M.; Nuzzo, S.; Oliveri, E.; Pant, L.M.; Paolucci, P.; Park, I.; Passeggio, G.; Pavlov, B.; Philipps, B.; Piccolo, D.; Postema, H.; Puig Baranac, A.; Radi, A.; Radogna, R.; Raffone, G.; Ranieri, A.; Rashevski, G.; Riccardi, C.; Rodozov, M.; Rodrigues, A.; Ropelewski, L.; RoyChowdhury, S.; Ryu, G.; Ryu, M.S.; Safonov, A.; Salva, S.; Saviano, G.; Sharma, A.; Sharma, A.; Sharma, R.; Shah, A.H.; Shopova, M.; Sturdy, J.; Sultanov, G.; Swain, S.K.; Szillasi, Z.; Talvitie, J.; Tatarinov, A.; Tuuva, T.; Vai, I.; Van Stenis, M.; Venditti, R.; Verhagen, E.; Verwilligen, P.; Vitulo, P.; Volkov, S.; Vorobyev, A.; Wang, D.; Wang, M.; Yang, U.; Yang, Y.; Yonamine, R.; Zaganidis, N.; Zenoni, F.; Zhang, A.

    2015-01-01

    The CMS Collaboration plans to equip the very forward muon system with triple-GEM detectors that can withstand the environment of the High-Luminosity LHC. This project is at the final stages of R&D and moving to production. An unprecedented large area of several 100 m2 are to be instrumented with GEM detectors which will be produced in six different sites around the world. A common construction and quality control procedure is required to ensure the performance of each detector. The quality control steps will include optical inspection, cleaning and baking of all materials and parts used to build the detector, leakage current tests of the GEM foils, high voltage tests, gas leak tests of the chambers and monitoring pressure drop vs. time, gain calibration to know the optimal operation region of the detector, gain uniformity tests, and studying the efficiency, noise and tracking performance of the detectors in a cosmic stand using scintillators.

  11. GEM Detectors in the Experiments at e+e- Colliders in BINP

    CERN Document Server

    Maltsev, T V

    2017-01-01

    Micro-pattern gaseous detectors possess a high spatial resolution in tens micron scale together with high rate capability up to 107 cm-2s-1. In addition, they have all advantages of gaseous detectors, such as relatively low costs per unit area, the possibility to equip a large area as well as a high uniformity. Cascaded Gas Electron Multiplier (GEM) based detectors are used in the collider experiments at Budker Institute of Nuclear Physics (BINP), and they are being developed for a number of new projects. In this article the review of GEM based detectors for the tagging system of the KEDR experiment at the VEPP-4M collider and for the DEUTERON facility at the VEPP-3 storage ring is presented. The GEM detector application of the CMD-3 detector upgrade at the VEPP-2000 collider and the Super τ Factory detector are discussed.

  12. Numerical Investigation on Electron and Ion Transmission of GEM-based Detectors

    Science.gov (United States)

    Bhattacharya, Purba; Sahoo, Sumanya Sekhar; Biswas, Saikat; Mohanty, Bedangadas; Majumdar, Nayana; Mukhopadhyay, Supratik

    2018-02-01

    ALICE at the LHC is planning a major upgrade of its detector systems, including the TPC, to cope with an increase of the LHC luminosity after 2018. Different R&D activities are currently concentrated on the adoption of the Gas Electron Multiplier (GEM) as the gas amplification stage of the ALICE-TPC upgrade version. The major challenge is to have low ion feedback in the drift volume as well as to ensure a collection of good percentage of primary electrons in the signal generation process. In the present work, Garfield simulation framework has been adopted to numerically estimate the electron transparency and ion backflow fraction of GEM-based detectors. In this process, extensive simulations have been carried out to enrich our understanding of the complex physical processes occurring within single, triple and quadruple GEM detectors. A detailed study has been performed to observe the effect of detector geometry, field configuration and magnetic field on the above mentioned characteristics.

  13. A new design using GEM-based technology for the CMS experiment

    CERN Document Server

    Ressegotti, Martina

    2017-01-01

    The muon system of the Compact Muon Solenoid (CMS) experiment at the LHC is currently not instrumented for pseudorapidity higher than abs(${\\eta}$)${ > 2.4}$. The main challenges to the installation of a detector in that position are the high particle flux to be sustained, a high level of radiation, and the ability to accomodate a multilevel detector into the small available space (less than 30 cm). A new back-to-back configuration of a Gas Electron Multiplier (GEM) detector is presented with the aim of developing a compact, multi-layer GEM detector. It is composed of two independent stacked triple-GEM detectors, positioned with the anodes toward the outside and sharing the same cathode plane, which is located at the center of the chamber, to reduce the total detector's thickness. A first prototype has been produced and tested with an X-Ray source and muon beam. First results on its performance are presented.

  14. Gas electron multipliers: Development of large area GEMS and spherical GEMS

    International Nuclear Information System (INIS)

    Pinto, Serge Duarte

    2011-08-01

    Gaseous radiation detectors have been a crucial part of high-energy physics instrumentation since the 1960s, when the first multiwire proportional counters were built. In the 1990s the first micropattern gas detectors (MPGDS) saw the light; with sub-millimeter feature sizes these novel detectors were faster and more accurate than their predecessors. The gas electron multiplier (GEM) is one of the most successful of these technologies. It is a charge multiplication structure made from a copper clad polymer foil, pierced with a regular and dense pattern of holes. I describe the properties and the application of GEMs and GEM. detectors, and the research and development I have done on this technology. Two of the main objectives were the development of large area GEMs (∝m 2 ) for particle physics experiments and GEMs with a spherical shape for X-ray or neutron diffraction detectors. Both have been realized, and the new techniques involved are finding their way to applications in research and industry. (orig.)

  15. Gas Electron Multipliers: Development of large area GEMs and spherical GEMs

    CERN Document Server

    Duarte Pinto, Serge; Brock, Ian

    2011-01-01

    Gaseous radiation detectors have been a crucial part of high-energy physics instrumentation since the 1960s, when the first multiwire proportional counters were built. In the 1990s the first micropattern gas detectors (MPGDs) saw the light; with sub-millimeter feature sizes these novel detectors were faster and more accurate than their predecessors. The gas electron multiplier (GEM) is one of the most successful of these technologies. It is a charge multiplication structure made from a copper clad polymer foil, pierced with a regular and dense pattern of holes. I will describe the properties and the application of GEMs and GEM detectors, and the research and development I have done on this technology. Two of the main objectives were the development of large area GEMs (~m^2) for particle physics experiments and GEMs with a spherical shape for x-ray or neutron diffraction detectors. Both have been realized, and the new techniques involved are finding their way to applications in research and industry.

  16. Gas electron multipliers. Development of large area GEMS and spherical GEMS

    Energy Technology Data Exchange (ETDEWEB)

    Pinto, Serge Duarte

    2011-08-15

    Gaseous radiation detectors have been a crucial part of high-energy physics instrumentation since the 1960s, when the first multiwire proportional counters were built. In the 1990s the first micropattern gas detectors (MPGDS) saw the light; with sub-millimeter feature sizes these novel detectors were faster and more accurate than their predecessors. The gas electron multiplier (GEM) is one of the most successful of these technologies. It is a charge multiplication structure made from a copper clad polymer foil, pierced with a regular and dense pattern of holes. I describe the properties and the application of GEMs and GEM. detectors, and the research and development I have done on this technology. Two of the main objectives were the development of large area GEMs ({proportional_to}m{sup 2}) for particle physics experiments and GEMs with a spherical shape for X-ray or neutron diffraction detectors. Both have been realized, and the new techniques involved are finding their way to applications in research and industry. (orig.)

  17. Microstructured boron foil scintillating G-GEM detector for neutron imaging

    Energy Technology Data Exchange (ETDEWEB)

    Fujiwara, Takeshi, E-mail: fujiwara-t@aist.go.jp [Research Institute for Measurement and Analytical Instrumentation, Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki (Japan); Center for Advanced Photonics, Neutron Beam Technology Team, RIKEN, Saitama (Japan); Bautista, Unico [Department of Nuclear Engineering and Management, The University of Tokyo, Tokyo (Japan); Philippine Nuclear Research Institute-Department of Science and Technology (PNRI-DOST), Commonwealth Avenue, Diliman, Quezon City (Philippines); Mitsuya, Yuki [Nuclear Professional School, The University of Tokyo, Tokai-mura, Naka-gun, Ibaraki (Japan); Takahashi, Hiroyuki [Department of Nuclear Engineering and Management, The University of Tokyo, Tokyo (Japan); Yamada, Norifumi L. [Neutron Science Laboratory, Institute of Material Structure Science, High Energy Accelerator Research Organization (KEK) (Japan); Otake, Yoshie; Taketani, Atsushi [Center for Advanced Photonics, Neutron Beam Technology Team, RIKEN, Saitama (Japan); Uesaka, Mitsuru [Nuclear Professional School, The University of Tokyo, Tokai-mura, Naka-gun, Ibaraki (Japan); Toyokawa, Hiroyuki [Research Institute for Measurement and Analytical Instrumentation, Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki (Japan)

    2016-12-01

    In this study, a new simple neutron imaging gaseous detector was successfully developed by combining a micro-structured {sup 10}B foil, a glass gas electron multiplier (G-GEM), and a mirror–lens–charge-coupled device (CCD)–camera system. The neutron imaging system consists of a chamber filled with Ar/CF{sub 4} scintillating gas mixture. Inside this system, the G-GEM is mounted for gas multiplication. The neutron detection in this system is based on the reaction between {sup 10}B and neutrons. A micro-structured {sup 10}B is developed to overcome the issue of low detection efficiency. Secondary electrons excite Ar/CF{sub 4} gas molecules, and high-yield visible photons are emitted from those excited gas molecules during the gas electron multiplication process in the G-GEM holes. These photons are easily detected by a mirror–lens–CCD–camera system. A neutron radiograph is then simply formed. We obtain the neutron images of different materials with a compact accelerator-driven neutron source. We confirm that the new scintillating G-GEM-based neutron imager works properly with low gamma ray sensitivity and exhibits a good performance as a new simple digital neutron imaging device.

  18. GEM photomultiplier operation in CF sub 4

    CERN Document Server

    Breskin, Amos; Chechik, R

    2002-01-01

    The properties of a 3-GEM (Gas Electron Multiplier) element photomultiplier, with a semitransparent CsI photocathode and CF sub 4 gas filling, are presented. Compared to other gas mixtures, such as CH sub 4 , Ar/CH sub 4 , Ar/N sub 2 and He/Ar/N sub 2 , CF sub 4 has superior performance: the highest gain, approaching 10 sup 7 , the fastest, 8 ns wide signal and the lowest photoelectron backscattering; the latter allows to reach photocathode quantum efficiency values approaching that in vacuum. The time resolution of the multi-GEM photomultiplier for single photoelectrons was measured to be 2 ns. These properties are of high relevance for applications in Cherenkov detectors and in tracking devices.

  19. X-Ray Polarimetry with GEMS

    Science.gov (United States)

    Strohmayer, Tod

    2011-01-01

    The polarization properties of cosmic X-ray sources are still largely unexplored. The Gravity and Extreme Magnetism SMEX (GEMS) will carry out the first sensitive X-ray polarization survey of a wide range of sources including; accreting compact objects (black holes and neutron stars), AGN, supernova remnants, magnetars and rotation-powered pulsars. GEMS employs grazing-incidence foil mirrors and novel time-projection chamber (TPC) polarimeters leveraging the photoelectric effect to achieve high polarization sensitivity in the 2 - 10 keV band. I will provide an update of the project status, illustrate the expected performance with several science examples, and provide a brief overview of the data analysis challenges

  20. GEM - A novel gaseous particle detector

    CERN Document Server

    Meinschad, T

    2005-01-01

    The work carried out within the framework of this Ph.D. deals with the construction of gaseous prototype detectors using Gas Electron Multiplier electrodes for the amplification of charges released by ionizing particles. The Gas Electron Multiplier (GEM) is a thin metal-clad polymer foil, etched with a high density of narrow holes, typically 50-100mm-2. On the application of a potential difference between the conductive top and bottom sides each hole acts as independent proportional counter. This new fast device permits to reach large amplification factors at high rates with a strong photon and ion-mediated feedback suppression due to the avalanche confinement in the GEM-holes. Here, in particular studies have been performed, which should prove, that the GEM-technology is applicable for an efficient measurement of single Cherenkov photons. These UV-photons can be detected in different ways. An elegant solution to develop large area RICH-detectors is to evaporate a pad-segmented readout-cathode of a multi-wire...

  1. Study of etching processes in the GEM detectors

    CERN Document Server

    Zavazieva, Darina

    2016-01-01

    Gaseous Electron Multiplier (GEM) detectors are known to operate stably at high gains and high particle fluxes. Though, at very high gains and fluxes it was observed that the insulating polyimide layer between the GEM electrodes gets etched, changing the original shape of the hole, and therefore varying the gain and the energy resolution of the detector. The idea of the project to observe degradation effect of the GEM foils during the Triple GEM detector operation in extreme conditions under X-ray radiation.

  2. Elsevier Overview of large area triple-GEM detectors for the CMS forward muon upgrade

    CERN Document Server

    Abbaneo, D; Abbrescia, M; Abi Akl, M; Aboamer, O; Acosta, D; Ahmad, A; Ahmed, W; Aleksandrov, A; Altieri, P; Asawatangtrakuldee, C; Aspell, P; Assran, Y; Awan, I; Bally, S; Ban, Y; Banerjee, S; Barashko, V; Barria, P; Bencze, G; Beni, N; Benussi, L; Bhopatkar, V; Bianco, S; Bos, J; Bouhali, O; Braghieri, A; Braibant, S; Buontempo, S; Calabria, C; Caponero, M; Caputo, C; Cassese, F; Castaneda, A; Cauwenbergh, S; Cavallo, F R; Celik, A; Choi, M; Choi, S; Christiansen, J; Cimmino, A; Colafranceschi, S; Colaleo, A; Conde Garcia, A; Czellar, S; Dabrowski, M M; De Lentdecker, G; De Oliveira, R; de Robertis, G; Dildick, S; Dorney, B; Endroczi, G; Errico, F; Fenyvesi, A; Ferry, S; Furic, I; Giacomelli, P; Gilmore, J; Golovtsov, V; Guiducci, L; Guilloux, F; Gutierrez, A; Hadjiiska, R M; Hauser, J; Hoepfner, K; Hohlmann, M; Hoorani, H; Iaydjiev, P; Jeng, Y G; Kamon, T; Karchin, P; Korytov, A; Krutelyov, S; Kumar, A; Kim, H; Lee, J; Lenzi, T; Litov, L; Loddo, F; Madorsky, A; Maerschalk, T; Maggi, M; Magnani, A; Mal, P K; Mandal, K; Marchioro, A; Marinov, A; Majumdar, N; Merlin, J A; Mitselmakher, G; Mohanty, A K; Mohapatra, A; Molnar, J; Muhammad, S; Mukhopadhyay, S; Naimuddin, M; Nuzzo, S; Oliveri, E; Pant, L M; Paolucci, P; Park, I; Passeggio, G; Pavlov, B; Philipps, B; Piccolo, D; Postema, H; Puig Baranac, A; Radi, A; Radogna, R; Raffone, G; Ranieri, A; Rashevski, G; Riccardi, C; Rodozov, M; Rodrigues, A; Ropelewski, L; RoyChowdhury, S; Ryu, G; Ryu, M S; Safonov, A; Salva, S; Saviano, G; Sharma, A; Sharma, A; Sharma, R; Shah, A H; Shopova, M; Sturdy, J; Sultanov, G; Swain, S K; Szillasi, Z; Talvitie, J; Tatarinov, A; Tuuva, T; Tytgat, M; Vai, I; Van Stenis, M; Venditti, R; Verhagen, E; Verwilligen, P; Vitulo, P; Volkov, S; Vorobyev, A; Wang, D; Wang, M; Yang, U; Yang, Y; Yonamine, R; Zaganidis, N; Zenoni, F; Zhang, A

    2017-01-01

    We report on the status of the project to install large-area triple-foil gas electron multiplier (GEM) detectors in the end-cap muon system of the Compact Muon Solenoid (CMS) experiment at the LHC operating at the high luminosity planned after the current period of data-taking (run 2). In the pseudo-rapidity region $1.6 < \\lvert\\eta\\rvert < 2.4$, the GEM detectors will suppress the rate of background triggers while maintaining high trigger efficiency for low transverse momentum muons, and enhancing the robustness of muon detection in the high-flux environment of the end-cap region. GEM detectors will also be used to extend the range of muon identification up to about $\\lvert\\eta\\rvert = 3.0$. We describe the design of the GEM chambers, readout electronics, and data acquisition system for the three stations in each endcap, located at increasing distances from the interaction point. For the intermediate station, the design is fixed and we describe plans to install several of the intermediate station dete...

  3. Promoting microbiology education through the iGEM synthetic biology competition.

    Science.gov (United States)

    Kelwick, Richard; Bowater, Laura; Yeoman, Kay H; Bowater, Richard P

    2015-08-01

    Synthetic biology has developed rapidly in the 21st century. It covers a range of scientific disciplines that incorporate principles from engineering to take advantage of and improve biological systems, often applied to specific problems. Methods important in this subject area include the systematic design and testing of biological systems and, here, we describe how synthetic biology projects frequently develop microbiology skills and education. Synthetic biology research has huge potential in biotechnology and medicine, which brings important ethical and moral issues to address, offering learning opportunities about the wider impact of microbiological research. Synthetic biology projects have developed into wide-ranging training and educational experiences through iGEM, the International Genetically Engineered Machines competition. Elements of the competition are judged against specific criteria and teams can win medals and prizes across several categories. Collaboration is an important element of iGEM, and all DNA constructs synthesized by iGEM teams are made available to all researchers through the Registry for Standard Biological Parts. An overview of microbiological developments in the iGEM competition is provided. This review is targeted at educators that focus on microbiology and synthetic biology, but will also be of value to undergraduate and postgraduate students with an interest in this exciting subject area. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  4. Gas Electron Multipler (GEM) detectors for parity-violating electron scattering experiments at Jefferson Lab

    Science.gov (United States)

    Matter, John; Gnanvo, Kondo; Liyanage, Nilanga; Solid Collaboration; Moller Collaboration

    2017-09-01

    The JLab Parity Violation In Deep Inelastic Scattering (PVDIS) experiment will use the upgraded 12 GeV beam and proposed Solenoidal Large Intensity Device (SoLID) to measure the parity-violating electroweak asymmetry in DIS of polarized electrons with high precision in order to search for physics beyond the Standard Model. Unlike many prior Parity-Violating Electron Scattering (PVES) experiments, PVDIS is a single-particle tracking experiment. Furthermore the experiment's high luminosity combined with the SoLID spectrometer's open configuration creates high-background conditions. As such, the PVDIS experiment has the most demanding tracking detector needs of any PVES experiment to date, requiring precision detectors capable of operating at high-rate conditions in PVDIS's full production luminosity. Developments in large-area GEM detector R&D and SoLID simulations have demonstrated that GEMs provide a cost-effective solution for PVDIS's tracking needs. The integrating-detector-based JLab Measurement Of Lepton Lepton Electroweak Reaction (MOLLER) experiment requires high-precision tracking for acceptance calibration. Large-area GEMs will be used as tracking detectors for MOLLER as well. The conceptual designs of GEM detectors for the PVDIS and MOLLER experiments will be presented.

  5. Evaluation of a GEM and CAT-based detector for radiation therapy beam monitoring

    International Nuclear Information System (INIS)

    Brahme, A.; Danielsson, M.; Iacobaeus, C.; Ostling, J.; Peskov, V.; Wallmark, M.

    2000-01-01

    We are developing a radiation therapy beam monitor for the Karolinska Institute. This monitor will consist of two consecutive detectors confined in one gas chamber: a 'keV-photon detector', which will allow diagnostic quality visualization of the patient, and a 'MeV-photon detector', that will measure the absolute intensity of the therapy beam and its position with respect to the patient. Both detectors are based on highly radiation resistant gas and solid photon to electron converters, combined with GEMs and a CAT as amplification structures. We have performed systematic studies of the high-rate characteristics of the GEM and the CAT, as well as tested the electron transfer through these electron multipliers and various types of converters. The tests show that the GEM and the CAT satisfy all requirements for the beam monitoring system. As a result of these studies we successfully developed and tested a full section of the beam monitor equipped with a MeV-photon converter placed between the GEM and the CAT

  6. The new cylindrical GEM inner tracker of BESIII arXiv

    CERN Document Server

    Lavezzi, L.; Amoroso, A.; Ferroli, R. Baldini; Bertani, M.; Bettoni, D.; Bianchi, F.; Calcaterra, A.; Canale, N.; Capodiferro, M.; Carassiti, V.; Cerioni, S.; Chai, JY.; Chiozzi, S.; Cibinetto, G.; Cossio, F.; Cotta Ramusino, A.; De Mori, F.; Destefanis, M.; Dong, J.; Evangelisti, F.; Farinelli, R.; Fava, L.; Felici, G.; Fioravanti, E.; Garzia, I.; Gatta, M.; Greco, M.; Leng, CY.; Li, H.; Maggiora, M.; Malaguti, R.; Marcello, S.; Melchiorri, M.; Mezzadri, G.; Mignone, M.; Morello, G.; Pacetti, S.; Patteri, P.; Pellegrino, J.; Pelosi, A.; Rivetti, A.; Rolo, M.D.; Savrie', M.; Scodeggio, M.; Soldani, E.; Sosio, S.; Spataro, S.; Tskhadadze, E.; Verma, S.; Wheadon, R.; Yan, L.

    The Cylindrical GEM-Inner Tracker (CGEM-IT) is the upgrade of the internal tracking system of the BESIII experiment. It consists of three layers of cylindrically-shaped triple GEMs, with important innovations with respect to the existing GEM detectors, in order to achieve the best performance with the lowest material budget. It will be the first cylindrical GEM running with analog readout inside a 1T magnetic field. The simultaneous measurement of both the deposited charge and the signal time will permit to use a combination of two algorithms to evaluate the spatial position of the charged tracks inside the CGEM-IT: the charge centroid and the micro time projection chamber modes. They are complementary and can cope with the asymmetry of the electron avalanche when running in magnetic field and with non-orthogonal incident tracks. To evaluate the behavior under different working settings, both planar chambers and the first cylindrical prototype have been tested during various test beams at CERN with 150 GeV/c ...

  7. Analysis of Mechanical Properties for GEM Foil

    CERN Document Server

    Chin, Yuk Ming

    2016-01-01

    In view of new assembly technique of the GEM detector; in which three foils stack is stretched to get the uniform gaps among the foils. We studied the mechanical properties of the foil material. We conditioned the samples in different environments to make them extra dry and wet. As holes are the major source of the charge amplification their deformation can effect the detector performance. Therefore in our studies we also studied at which level of the stress the holes deformation is seen. These tensile and holes deformation studies can help to optimize the stress during detector assembly.

  8. Cold Fronts in RegCM/HadGEM simulations over South America

    Science.gov (United States)

    Pampuch, Luana; Marcos de Jesus, Eduardo; Porfírio da Rocha, Rosmeri; Ambrizzi, Tércio

    2017-04-01

    Cold front is one of the most important systems that contribute for precipitation over South America. The representation of this system in climate models is important for a better representation of the precipitation. The Regional Climate Model RegCM is widely used for climate studies in South America, being important to understand how this model represents the cold fronts. A climatology (from 1979-2004) of the number of cold fronts in each season for RegCM4 simulations over South America CORDEX domain nested in HadGEM2-ES. The simulated climatology was compared with ERA-Interim reanalysis cold fronts climatology over the South America and adjacent South Atlantic Ocean. The cold fronts tracking for the model and the reanalysis were performed using an objective methodology based on decrease of air temperature in 925hPa, shift of meridional wind in 925hPa from northern to southern quadrant and increased in sea level pressure. The main differences were observed on summer and winter. On summer the model overestimate the number of cold fronts over southeastern South America and adjacent Atlantic Ocean; and underestimate it over central-south Argentina and Atlantic Ocean. On winter, the signs were opposite of that summer. On autumn and spring the differences were smaller and occurs mainly over all South Atlantic and north Argentina.

  9. GEM 10B Satellite gravity data and Nigerian oil prospects

    International Nuclear Information System (INIS)

    Garde, S.C.; Kim, W.Y.

    1984-11-01

    Extension of the hydrocarbon rich Benue depression and the Niger delta basin in the bight of Benin is construed from the gravity data of Gravity Earth Model (GEM) 10B Satellite, published by NASA, Godard Space Flight Centre in 1977. This interpretation is based on the supposition that: i) the depth of a buried horizontal cylinder can be estimated by the Fourier transform of the vertical gravity field [Odegard and Berg, Geophys., 30, No. 3, 424-438 (1965)]; and ii) the oil horizons of southern Nigeria are basically connected to the separation of South American and African plates [Burke et al., African Geology, Ibadan Univ. Press, Ibadan, Nigeria, p. 187-204 (1970)]. (author)

  10. Extending the ISC-GEM Global Earthquake Instrumental Catalogue

    Science.gov (United States)

    Di Giacomo, Domenico; Engdhal, Bob; Storchak, Dmitry; Villaseñor, Antonio; Harris, James

    2015-04-01

    After a 27-month project funded by the GEM Foundation (www.globalquakemodel.org), in January 2013 we released the ISC-GEM Global Instrumental Earthquake Catalogue (1900 2009) (www.isc.ac.uk/iscgem/index.php) as a special product to use for seismic hazard studies. The new catalogue was necessary as improved seismic hazard studies necessitate that earthquake catalogues are homogeneous (to the largest extent possible) over time in their fundamental parameters, such as location and magnitude. Due to time and resource limitation, the ISC-GEM catalogue (1900-2009) included earthquakes selected according to the following time-variable cut-off magnitudes: Ms=7.5 for earthquakes occurring before 1918; Ms=6.25 between 1918 and 1963; and Ms=5.5 from 1964 onwards. Because of the importance of having a reliable seismic input for seismic hazard studies, funding from GEM and two commercial companies in the US and UK allowed us to start working on the extension of the ISC-GEM catalogue both for earthquakes that occurred beyond 2009 and for earthquakes listed in the International Seismological Summary (ISS) which fell below the cut-off magnitude of 6.25. This extension is part of a four-year program that aims at including in the ISC-GEM catalogue large global earthquakes that occurred before the beginning of the ISC Bulletin in 1964. In this contribution we present the updated ISC GEM catalogue, which will include over 1000 more earthquakes that occurred in 2010 2011 and several hundreds more between 1950 and 1959. The catalogue extension between 1935 and 1949 is currently underway. The extension of the ISC-GEM catalogue will also be helpful for regional cross border seismic hazard studies as the ISC-GEM catalogue should be used as basis for cross-checking the consistency in location and magnitude of those earthquakes listed both in the ISC GEM global catalogue and regional catalogues.

  11. ISC-GEM: Global Instrumental Earthquake Catalogue (1900-2009) I. Location and Seismicity Patterns

    Science.gov (United States)

    Bondar, I.; Engdahl, E. R.; Villasenor, A.; Storchak, D. A.

    2012-12-01

    We present the final results of a two-year project sponsored by the GEM (Global Earthquake Model) Foundation. The ISC-GEM global catalogue consists of some 19 thousand instrumentally recorded, moderate to large earthquakes, spanning 110 years of seismicity. We relocated all events in the catalogue using a two-tier approach. The EHB location methodology (Engdahl et al., 1998) was applied first to obtain improved hypocentres with special focus on the depth determination. The locations were further refined in the next step by fixing the depths to those from the EHB analysis and applying the new ISC location algorithm (Bondár and Storchak, 2011) that reduces location bias by accounting for correlated travel-time prediction error structure. To facilitate the relocation effort, some 900,000 seismic P and S wave arrival-time data were added to the ISC database for the period between 1904 and 1963, either from original station bulletins in the ISC archive or by digitizing the scanned images of the ISS bulletin (Villaseñor and Engdahl, 2005; 2007). Although no substantial amount of new phase data were acquired for the modern period (1964-2009), the number of phases used in the location has still increased by 3 million, owing to fact that both the EHB and ISC locators use all ak135 (Kennett et al., 1995) phases in the location. We show that the relocation effort yielded substantially improved locations, especially in the first half of the 20th century; we demonstrate significant improvements in focal depth estimates in subduction zones and other seismically active regions; and we show that the ISC-GEM catalogue provides an improved view of 110 years of global seismicity of the Earth. The ISC-GEM Global Instrumental Earthquake Catalogue represents the final product of one of the ten global components in the GEM program, and will be made available to researchers at the ISC (www.isc.ac.uk) website.

  12. PREFACE: Science's gem: diamond science 2009 Science's gem: diamond science 2009

    Science.gov (United States)

    Mainwood, Alison; Newton, Mark E.; Stoneham, Marshall

    2009-09-01

    dislocations. The understanding of the critical processes that are involved in CVD diamond growth are becoming clearer. Two papers in this issue model it on a microscopic scale [11, 12], and a further two explore the practical techniques [13, 14] in order to lead to improvement in deposition techniques. Diamond is emerging as an engineering material [3] with its cost no longer regarded as prohibitive even for some large-scale uses, such as the fusion reactor first wall. It is striking how few useful dopants can be put into diamond in a controlled way. The studies reported here, whether theory or experiment, concentrate on phosphorus [14] as the donor, and demonstrate that boron (although deep in semiconductor terms,) can act as the acceptor [3] in practical devices. Other impurities, with deeper levels, such as nitrogen [15], with the muon as an honorary hydrogen [16], are studied in depth. Here, many of the characterization techniques developed over several decades have been brought to bear, to attempt to quantify impurities and defects and ultimately assist in improving the crystal quality [17, 18, 15]. However, further, more novel techniques such as reflection anisotropy spectroscopy [19] and luminescence lifetime mapping [20] have been introduced to diamond in this issue, and one can see how such techniques might play a crucial role in areas such as systems for quantum information processing. The presence and migration of radiation damage defects [21, 22], vacancies and interstitials, and vacancy clusters can dramatically influence the exploitable properties of diamond [23, 24]. It is now apparent that charge traps not only impact on electrical properties, but also on the colour of diamond and that thermo-chromic and photo-chromic effects are more common than previously thought [25, 23]. Combinations, like the negatively charged nitrogen-vacancy centre, have proved impressive in quantum information studies [26]. But diamond has yet to benefit from the sort of dopant

  13. The Mitochondrial GTPase Gem1 Contributes to the Cell Wall Stress Response and Invasive Growth of Candida albicans

    Directory of Open Access Journals (Sweden)

    Barbara Koch

    2017-12-01

    Full Text Available The interactions of mitochondria with the endoplasmic reticulum (ER are crucial for maintaining proper mitochondrial morphology, function and dynamics. This enables cells to utilize their mitochondria optimally for energy production and anabolism, and it further provides for metabolic control over developmental decisions. In fungi, a key mechanism by which ER and mitochondria interact is via a membrane tether, the protein complex ERMES (ER-Mitochondria Encounter Structure. In the model yeast Saccharomyces cerevisiae, the mitochondrial GTPase Gem1 interacts with ERMES, and it has been proposed to regulate its activity. Here we report on the first characterization of Gem1 in a human fungal pathogen. We show that in Candida albicans Gem1 has a dominant role in ensuring proper mitochondrial morphology, and our data is consistent with Gem1 working with ERMES in this role. Mitochondrial respiration and steady state cellular phospholipid homeostasis are not impacted by inactivation of GEM1 in C. albicans. There are two major virulence-related consequences of disrupting mitochondrial morphology by GEM1 inactivation: C. albicans becomes hypersusceptible to cell wall stress, and is unable to grow invasively. In the gem1Δ/Δ mutant, it is specifically the invasive capacity of hyphae that is compromised, not the ability to transition from yeast to hyphal morphology, and this phenotype is shared with ERMES mutants. As a consequence of the hyphal invasion defect, the gem1Δ/Δ mutant is drastically hypovirulent in the worm infection model. Activation of the mitogen activated protein (MAP kinase Cek1 is reduced in the gem1Δ/Δ mutant, and this function could explain both the susceptibility to cell wall stress and lack of invasive growth. This result establishes a new, respiration-independent mechanism of mitochondrial control over stress signaling and hyphal functions in C. albicans. We propose that ER-mitochondria interactions and the ER

  14. New Approach for 2D Readout of GEM Detectors

    International Nuclear Information System (INIS)

    Hasell, Douglas K.

    2011-01-01

    Detectors based on Gas Electron Multiplication (GEM) technology are becoming more and more widely used in nuclear and high energy physics and are being applied in astronomy, medical physics, industry, and homeland security. GEM detectors are thin, low mass, insensitive to magnetic fields, and can currently provide position resolutions down to ∼50 microns. However, the designs for reconstructing the position, in two dimensions (2D), of the charged particles striking a GEM detector are often complicated to fabricate and expensive. The objective of this proposal is to investigate a simpler procedure for producing the two dimensional readout layer of GEM detectors using readily available printed circuit board technology which can be tailored to the detector requirements. We will use the established GEM laboratory and facilities at M.I.T. currently employed in developing GEM detectors for the STAR forward tracking upgrade to simplify the testing and evaluation of the new 2D readout designs. If this new design proves successful it will benefit future nuclear and high energy physics experiments already being planned and will similarly extend and simplify the application of GEM technology to other branches of science, medicine, and industry. These benefits would be not only in lower costs for fabrication but also it increased flexibility for design and application.

  15. Gems of combinatorial optimization and graph algorithms

    CERN Document Server

    Skutella, Martin; Stiller, Sebastian; Wagner, Dorothea

    2015-01-01

    Are you looking for new lectures for your course on algorithms, combinatorial optimization, or algorithmic game theory?  Maybe you need a convenient source of relevant, current topics for a graduate student or advanced undergraduate student seminar?  Or perhaps you just want an enjoyable look at some beautiful mathematical and algorithmic results, ideas, proofs, concepts, and techniques in discrete mathematics and theoretical computer science?   Gems of Combinatorial Optimization and Graph Algorithms is a handpicked collection of up-to-date articles, carefully prepared by a select group of international experts, who have contributed some of their most mathematically or algorithmically elegant ideas.  Topics include longest tours and Steiner trees in geometric spaces, cartograms, resource buying games, congestion games, selfish routing, revenue equivalence and shortest paths, scheduling, linear structures in graphs, contraction hierarchies, budgeted matching problems, and motifs in networks.   This ...

  16. Portable XRF: A Tool for the Study of Corundum Gems

    Directory of Open Access Journals (Sweden)

    Barone Germana

    2017-09-01

    Full Text Available Origin of gemstones is a key aspect not only in gemological field but also in Cultural Heritage studies, for the correct evaluation of precious artifacts. The studies on gems require the application of non-invasive and non-destructive methods; among them, portable spectroscopic techniques has been demonstrated as powerful tools, providing a fingerprint of gems for origin and provenance determination. In this study, portable XRF spectroscopy has been applied to test the potential of the technique for the origin determination of corundum gems. The obtained results allowed distinguishing natural and synthetic rubies and sapphires.

  17. A triple-GEM telescope for the TOTEM experiment

    CERN Document Server

    Lami, S; Oliveri, E; Ropelewski, Leszek; Turini, N

    2007-01-01

    The TOTEM experiment at LHC has chosen the triple Gas Electron Multiplier (GEM) technology for its T2 telescope which will provide charged track reconstruction in the rapidity range 5.3<|eta|<6.5 and a fully inclusive trigger for diffractive events. GEMs are gas-filled detectors that have the advantageous decoupling of the charge amplification structure from the charge collection and readout structure. Furthermore, they combine good spatial resolution with very high rate capability and a good resistance to radiation. Results from a detailed T2 GEM simulation and from laboratory tests on a final design detector performed at CERN are presented.

  18. Triple GEM detector sensitivity simulations with Geant4 for the CMS Forward Muon Upgrade at CERN LHC

    Science.gov (United States)

    Zenoni, Florian; CMS GEM Collaboration

    2015-04-01

    Triple Gas Electron Multiplier (GEM) detectors are being developed for the forward muon upgrade of the CMS experiment in Phase 2 of the CERN LHC. After the second long LHC shutdown, their implementation will take place for the GE1/1 system in the 1 . 5 technology can improve the muon track reconstruction and identification capabilities of the forward detector. The Triple GEMs will work in a hostile radiation background (several hundreds of Hz/cm2) mostly made of photons, neutrons, electrons and positrons. To understand how this background could affect the detectors' functionality it is important to know the sensitivity to these kinds of radiation. The goal of this work is to estimate the sensitivity of Triple GEMs to background particles in the CMS cavern environment, thanks to the latest updates of GEANT4, a toolkit for the simulation of the passage of particles through matter.

  19. Simulation of in-cloud icing events on Mount Washington with the GEM-LAM

    Science.gov (United States)

    Yang, Jing; Jones, Kathleen F.; Yu, Wei; Morris, Robert

    2012-09-01

    In-cloud icing on structures such as transmission lines and wind turbines is an important consideration both for design and operations. It often occurs in coastal areas and over high terrain, where there are virtually no systematic observations. The regional mesoscale model GEM-LAM of the Canadian Meteorological Center (CMC) was used to model three historical icing events on Mount Washington, where observational data were available. These three events are representative of the most frequent low level wind directions for seven available observation periods. A newly developed sophisticated two-moment microphysics scheme (Milbrandt-Yau) is used in GEM-LAM. The simulated cloud properties and other meteorological data are compared with near surface observational data. Simulation results from the 1-km resolution run agree best with the observations, with an average RMSE (root mean square error) of 1.6°C for near surface temperature, 4.6 m s-1 for wind speed, 0.23 g m-3 for liquid water content, and 5.8 μm for the median volume droplet diameter. These simulated meteorological fields and cloud properties were used as inputs to a cylindrical sleeve icing model. The modeled icing rate from the GEM-LAM simulated fields follows the temporal evolution of the observed one with average RMSE of 1.53 g m-1 min-1 compared to an average measured icing rate of 1.98 g m-1 min-1 for all the three cases.

  20. Production and performance of LHCb triple-GEM detectors equipped with the dedicated CARDIAC-GEM front-end electronics

    Energy Technology Data Exchange (ETDEWEB)

    Alfonsi, M. [Laboratori Nazionali di Frascati - INFN (Italy)]. E-mail: matteo.alfonsi@lnf.infn.it; Bencivenni, G. [Laboratori Nazionali di Frascati - INFN (Italy); Bonivento, W. [Sezione INFN di Cagliari (Italy); Cardelli, E. [Sezione INFN di Cagliari (Italy); Cardini, A. [Sezione INFN di Cagliari (Italy); De Simone, P. [Laboratori Nazionali di Frascati - INFN (Italy); Domenici, D. [Laboratori Nazionali di Frascati - INFN (Italy); Murtas, F. [Laboratori Nazionali di Frascati - INFN (Italy); Pinci, D. [Sezione INFN di Roma 1 (Italy); Poli Lener, M. [Laboratori Nazionali di Frascati - INFN (Italy); Raspino, D. [Sezione INFN di Cagliari (Italy); Saitta, B. [Sezione INFN di Cagliari (Italy)

    2007-03-01

    The production of the triple-GEM detectors for the innermost region of the first muon station of the LHCb experiment has started in February 2006, and is foreseen to be completed by the end of July. The final design of the detector and the construction procedure and tools, as well as the quality controls are defined. The performances of each detector, composed by two triple-GEM chambers equipped with dedicated CARDIAC-GEM front-end electronics, are studied with a cosmic ray telescope. The cosmic ray telescope has been set up including all the final off-detector components.

  1. Construction, test and commissioning of the triple-GEM tracking detector for COMPASS

    CERN Document Server

    Altunbas, M C; Dehmelt, K; Ehlers, J; Konorov, I; Gandi, A; Kappler, S; Ketzer, B; De Oliveira, R; Paul, S; Placci, Alfredo; Ropelewski, Leszek; Sauli, Fabio; Simon, F; Van Stenis, M

    2002-01-01

    The Small Area Tracking system of the COMPASS experiment at CERN includes a set of 20 large area, fast position-sensitive Gas Electron Multiplier (GEM) detectors, designed to reliably operate in the harsh radiation environment of the experiment. We describe in detail the design, choice of materials, assembly procedures and quality controls used to manufacture the devices. The test procedure in the laboratory, the performance in test beams and in the initial commissioning phase in the experiment are presented and discussed.

  2. Review of GEM Radiation Belt Dropout and Buildup Challenges

    Science.gov (United States)

    Tu, Weichao; Li, Wen; Morley, Steve; Albert, Jay

    2017-04-01

    In Summer 2015 the US NSF GEM (Geospace Environment Modeling) focus group named "Quantitative Assessment of Radiation Belt Modeling" started the "RB dropout" and "RB buildup" challenges, focused on quantitative modeling of the radiation belt buildups and dropouts. This is a community effort which includes selecting challenge events, gathering model inputs that are required to model the radiation belt dynamics during these events (e.g., various magnetospheric waves, plasmapause and density models, electron phase space density data), simulating the challenge events using different types of radiation belt models, and validating the model results by comparison to in situ observations of radiation belt electrons (from Van Allen Probes, THEMIS, GOES, LANL/GEO, etc). The goal is to quantitatively assess the relative importance of various acceleration, transport, and loss processes in the observed radiation belt dropouts and buildups. Since 2015, the community has selected four "challenge" events under four different categories: "storm-time enhancements", "non-storm enhancements", "storm-time dropouts", and "non-storm dropouts". Model inputs and data for each selected event have been coordinated and shared within the community to establish a common basis for simulations and testing. Modelers within and outside US with different types of radiation belt models (diffusion-type, diffusion-convection-type, test particle codes, etc.) have participated in our challenge and shared their simulation results and comparison with spacecraft measurements. Significant progress has been made in quantitative modeling of the radiation belt buildups and dropouts as well as accessing the modeling with new measures of model performance. In this presentation, I will review the activities from our "RB dropout" and "RB buildup" challenges and the progresses achieved in understanding radiation belt physics and improving model validation and verification.

  3. Wits Post Graduate Symposium Poster - iGEM

    CSIR Research Space (South Africa)

    Millroy, L

    2010-08-01

    Full Text Available This document is a poster providing details of the 2010 International Genetically Engineered Machines (iGEM) competition. The origins of the competition, as well as criteria, judging, sponsors, topic and team, are briefly described....

  4. SYNTHESIS AND POLYMERIZATION OF GEM-METHYL(VINYLBENZYL)TETRACHLOROCYCLOTRIPHOSPHAZENE

    NARCIS (Netherlands)

    BOSSCHER, G; VANDEGRAMPEL, JC

    A new styrene-substituted chlorocyclotriphosphazene, gem-methyl(vinylbenzyl) tetrachlorocyclotriphosphazene, has been prepared from vinylbenzylmagnesium chloride and hexachlorocyclotriphosphazene. The organosubstituted chlorocyclotriphosphazene has been used in radical homo- and copolymerization

  5. International Genetically Engineered Machine (iGEM) Competition

    CSIR Research Space (South Africa)

    Sparrow, RW

    2010-07-01

    Full Text Available iGEM, the International Genetically Engineered Machine competition, is an initiative from MIT and has become the premiere undergraduate synthetic biology competition. The competing teams consist of students who work on a synthetic biology project...

  6. Modeling of System Families

    National Research Council Canada - National Science Library

    Feiler, Peter

    2007-01-01

    .... The Society of Automotive Engineers (SAE) Architecture Analysis & Design Language (AADL) is an industry-standard, architecture-modeling notation specifically designed to support a component- based approach to modeling embedded systems...

  7. Modelling Railway Interlocking Systems

    DEFF Research Database (Denmark)

    Lindegaard, Morten Peter; Viuf, P.; Haxthausen, Anne Elisabeth

    2000-01-01

    In this report we present a model of interlocking systems, and describe how the model may be validated by simulation. Station topologies are modelled by graphs in which the nodes denote track segments, and the edges denote connectivity for train traÆc. Points and signals are modelled by annotatio...

  8. GEM, Fuel Cycle Cost and Economics for Thermal Reactor, Present Worth Analysis

    International Nuclear Information System (INIS)

    Hughes, J.A.; Hang, D.F.

    1974-01-01

    1- Description of problem or function: GEM is used to predict fuel cycle costs for any type nuclear system (i.e., BWR, HTGR, PWR, LMFBR, GCFR,... ). The current version is limited to thermal reactors. GEM is designed for production use by large utilities which have several reactor types on their system. GEM has been written so as to accommodate all major fuel management activities undertaken by a utility - (1) fuel bid analysis, (2) evaluation of actual day to day operation, and (3) system simulation and optimization studies. 2 - Method of solution: Costs are calculated using present-worth techniques and continuous compounding. The equations are based on an investor-owned utility capitalization structure which easily covers the range of industrial, private, and public (government) owned utilities. Three distinct types of analysis (cash flow, allocated costs, yearly cash flow) are performed, each yielding identical results. Using these as a basis many other analyses are undertaken. 3 - Restrictions on the complexity of the problem: Dimensions of all arrays are carried as variables throughout the analysis. The maximum size of each array is set by the user in program MAIN. Current values are set so that maxima are: 50 batches per case study, 20 year batch life, 30 year case study, 120 batch burn time-steps, 20 individual payments (sales) associated with each cost component

  9. Performance of an optical readout GEM-based TPC

    International Nuclear Information System (INIS)

    Margato, L.M.S.; Fraga, F.A.F.; Fetal, S.T.G.; Fraga, M.M.F.R.; Balau, E.F.S.; Blanco, A.; Marques, R. Ferreira; Policarpo, A.J.P.L

    2004-01-01

    We report on the operation of a GEM-based small TPC using an optical readout. The detector was operated with a mixture of Ar+CF 4 using 5.48 MeV alpha particles obtained from a 241 Am source and the GEM scintillation was concurrently read by a CCD camera and a photomultiplier. Precision collimators were used to define the track orientation. Qualitative results on the accuracy of the track angle, length and charge deposition measurements are presented

  10. BoNus: Development and use of a radial TPC using cylindrical GEMs

    International Nuclear Information System (INIS)

    A specialized system of target and detector was developed at Jefferson Lab to provide new access to information about neutron structure from electron-neutron interactions. It allows identification and measurement of spectator protons produced in e - d→e - p s X scattering events. The detector is a radial time-projection chamber optimized for the acceptance of low-momentum protons. Gas gain is provided by three cascaded curved Gas Electron Multipliers (GEMs), the first application of GEMs in any configuration other than flat. This article provides details about the development and construction of the detector, its performance, and the analysis of the data from the successful running of its first physics experiment

  11. Studies on GEM modules for a large prototype TPC for the ILC

    International Nuclear Information System (INIS)

    Tsionou, Dimitra

    2016-12-01

    The International Linear Collider (ILC) is a future electron-positron collider with centre of mass energy of 500-1000 GeV. The International Large Detector (ILD) is one of two detector concepts at the ILC. Its high precision tracking system consists of Silicon sub-detectors and a Time Projection Chamber (TPC) equipped with micro-pattern gas detectors (MPGDs). Within the framework of the LCTPC collaboration, a Large Prototype (LP) TPC has been built as a demonstrator. This prototype has been equipped with Gas Electron Multiplier (GEM) modules and studied with electron beams of energies 1-6 GeV at the DESY test beam facility. The performance of the prototype detector and the extrapolation to the ILD TPC is presented here. In addition, ongoing optimisation studies and R and D; activities in order to prepare the next GEM module iteration are discussed.

  12. Studies on GEM modules for a Large Prototype TPC for the ILC

    International Nuclear Information System (INIS)

    Tsionou, Dimitra

    2017-01-01

    The International Linear Collider (ILC) is a future electron–positron collider with centre of mass energy of 500–1000 GeV. The International Large Detector (ILD) is one of two detector concepts at the ILC. Its high precision tracking system consists of Silicon sub-detectors and a Time Projection Chamber (TPC) equipped with micro-pattern gas detectors (MPGDs). Within the framework of the LCTPC collaboration, a Large Prototype (LP) TPC has been built as a demonstrator. This prototype has been equipped with Gas Electron Multiplier (GEM) modules and studied with electron beams of energies 1–6 GeV at the DESY test beam facility. The performance of the prototype detector and the extrapolation to the ILD TPC is presented here. In addition, ongoing optimisation studies and R&D activities in order to prepare the next GEM module iteration are discussed.

  13. Performance Verification of the Gravity and Extreme Magnetism Small Explorer GEMS X-Ray Polarimeter

    Science.gov (United States)

    Enoto, Teruaki; Black, J. Kevin; Kitaguchi, Takao; Hayato, Asami; Hill, Joanne E.; Jahoda, Keith; Tamagawa, Toru; Kanako, Kenta; Takeuchi, Yoko; Yoshikawa, Akifumi; hide

    2014-01-01

    olarimetry is a powerful tool for astrophysical observations that has yet to be exploited in the X-ray band. For satellite-borne and sounding rocket experiments, we have developed a photoelectric gas polarimeter to measure X-ray polarization in the 2-10 keV range utilizing a time projection chamber (TPC) and advanced micro-pattern gas electron multiplier (GEM) techniques. We carried out performance verification of a flight equivalent unit (1/4 model) which was planned to be launched on the NASA Gravity and Extreme Magnetism Small Explorer (GEMS) satellite. The test was performed at Brookhaven National Laboratory, National Synchrotron Light Source (NSLS) facility in April 2013. The polarimeter was irradiated with linearly-polarized monochromatic X-rays between 2.3 and 10.0 keV and scanned with a collimated beam at 5 different detector positions. After a systematic investigation of the detector response, a modulation factor greater than or equal to 35% above 4 keV was obtained with the expected polarization angle. At energies below 4 keV where the photoelectron track becomes short, diffusion in the region between the GEM and readout strips leaves an asymmetric photoelectron image. A correction method retrieves an expected modulation angle, and the expected modulation factor, approximately 20% at 2.7 keV. Folding the measured values of modulation through an instrument model gives sensitivity, parameterized by minimum detectable polarization (MDP), nearly identical to that assumed at the preliminary design review (PDR).

  14. RSMASS system model development

    International Nuclear Information System (INIS)

    Marshall, A.C.; Gallup, D.R.

    1998-01-01

    RSMASS system mass models have been used for more than a decade to make rapid estimates of space reactor power system masses. This paper reviews the evolution of the RSMASS models and summarizes present capabilities. RSMASS has evolved from a simple model used to make rough estimates of space reactor and shield masses to a versatile space reactor power system model. RSMASS uses unique reactor and shield models that permit rapid mass optimization calculations for a variety of space reactor power and propulsion systems. The RSMASS-D upgrade of the original model includes algorithms for the balance of the power system, a number of reactor and shield modeling improvements, and an automatic mass optimization scheme. The RSMASS-D suite of codes cover a very broad range of reactor and power conversion system options as well as propulsion and bimodal reactor systems. Reactor choices include in-core and ex-core thermionic reactors, liquid metal cooled reactors, particle bed reactors, and prismatic configuration reactors. Power conversion options include thermoelectric, thermionic, Stirling, Brayton, and Rankine approaches. Program output includes all major component masses and dimensions, efficiencies, and a description of the design parameters for a mass optimized system. In the past, RSMASS has been used as an aid to identify and select promising concepts for space power applications. The RSMASS modeling approach has been demonstrated to be a valuable tool for guiding optimization of the power system design; consequently, the model is useful during system design and development as well as during the selection process. An improved in-core thermionic reactor system model RSMASS-T is now under development. The current development of the RSMASS-T code represents the next evolutionary stage of the RSMASS models. RSMASS-T includes many modeling improvements and is planned to be more user-friendly. RSMASS-T will be released as a fully documented, certified code at the end of

  15. A GEM readout with radial zigzag strips and linear charge-sharing response

    Science.gov (United States)

    Zhang, Aiwu; Hohlmann, Marcus; Azmoun, Babak; Purschke, Martin L.; Woody, Craig

    2018-04-01

    We study the position sensitivity of radial zigzag strips intended to read out large GEM detectors for tracking at future experiments. Zigzag strips can cover a readout area with fewer strips than regular straight strips while maintaining good spatial resolution. Consequently, they can reduce the number of required electronic channels and related cost for large-area GEM detector systems. A non-linear relation between incident particle position and hit position measured from charge sharing among zigzag strips was observed in a previous study. We significantly reduce this non-linearity by improving the interleaving of adjacent physical zigzag strips. Zigzag readout structures are implemented on PCBs and on a flexible foil and are tested using a 10 cm × 10 cm triple-GEM detector scanned with a strongly collimated X-ray gun on a 2D motorized stage. Angular resolutions of 60-84 μrad are achieved with a 1.37 mrad angular strip pitch at a radius of 784 mm. On a linear scale this corresponds to resolutions below 100 μm.

  16. Numerical Investigation on Electron and Ion Transmission of GEM-based Detectors

    Directory of Open Access Journals (Sweden)

    Bhattacharya Purba

    2018-01-01

    Full Text Available ALICE at the LHC is planning a major upgrade of its detector systems, including the TPC, to cope with an increase of the LHC luminosity after 2018. Different R&D activities are currently concentrated on the adoption of the Gas Electron Multiplier (GEM as the gas amplification stage of the ALICE-TPC upgrade version. The major challenge is to have low ion feedback in the drift volume as well as to ensure a collection of good percentage of primary electrons in the signal generation process. In the present work, Garfield simulation framework has been adopted to numerically estimate the electron transparency and ion backflow fraction of GEM-based detectors. In this process, extensive simulations have been carried out to enrich our understanding of the complex physical processes occurring within single, triple and quadruple GEM detectors. A detailed study has been performed to observe the effect of detector geometry, field configuration and magnetic field on the above mentioned characteristics.

  17. Systemic resilience model

    International Nuclear Information System (INIS)

    Lundberg, Jonas; Johansson, Björn JE

    2015-01-01

    It has been realized that resilience as a concept involves several contradictory definitions, both for instance resilience as agile adjustment and as robust resistance to situations. Our analysis of resilience concepts and models suggest that beyond simplistic definitions, it is possible to draw up a systemic resilience model (SyRes) that maintains these opposing characteristics without contradiction. We outline six functions in a systemic model, drawing primarily on resilience engineering, and disaster response: anticipation, monitoring, response, recovery, learning, and self-monitoring. The model consists of four areas: Event-based constraints, Functional Dependencies, Adaptive Capacity and Strategy. The paper describes dependencies between constraints, functions and strategies. We argue that models such as SyRes should be useful both for envisioning new resilience methods and metrics, as well as for engineering and evaluating resilient systems. - Highlights: • The SyRes model resolves contradictions between previous resilience definitions. • SyRes is a core model for envisioning and evaluating resilience metrics and models. • SyRes describes six functions in a systemic model. • They are anticipation, monitoring, response, recovery, learning, self-monitoring. • The model describes dependencies between constraints, functions and strategies

  18. Selected System Models

    Science.gov (United States)

    Schmidt-Eisenlohr, F.; Puñal, O.; Klagges, K.; Kirsche, M.

    Apart from the general issue of modeling the channel, the PHY and the MAC of wireless networks, there are specific modeling assumptions that are considered for different systems. In this chapter we consider three specific wireless standards and highlight modeling options for them. These are IEEE 802.11 (as example for wireless local area networks), IEEE 802.16 (as example for wireless metropolitan networks) and IEEE 802.15 (as example for body area networks). Each section on these three systems discusses also at the end a set of model implementations that are available today.

  19. GEM*STAR: Time for an Alternative Way Forward

    Science.gov (United States)

    Vogelaar, R. Bruce

    2011-10-01

    The presumption that nuclear reactors will retain their role in global energy production is constantly being challenged - even more so following recent events at Fukushima. Nuclear energy, despite being ``green,'' has inexorably been coupled in the public mind with three paramount concerns: safety, weapons proliferation, and waste (and then ultimately cost). Over the past four decades, the safety of deployed fleets has greatly improved, yet the capital and political costs of a ``nuclear energy option'' appear insurmountable in several countries. The US approach to civilian nuclear energy has become deeply entrenched, first through choices made by the military, and then by the deployed nuclear reactor fleet. This extends to the research agencies as well, to the point where basic sciences and nuclear energy operate in separate spheres. But technologies and priorities have changed, and the time has arrived where a transformative re-think of nuclear energy is not only possible, but urgent. And nuclear physicists are uniquely positioned to accomplish this. This talk will show that by asking, and answering,``what would an accelerator-driven civilian nuclear energy program look like,'' ADNA Corporation's GEM*STAR design directly addresses all three fundamental concerns: safety, proliferation, and waste - and also the final hurdle: cost. GEM*STAR is not an ``add-on'' (to either Project-X, or GEN III+), but rather a base-line energy production capacity, for either electricity or transport fuel production. It integrates and advances the molten-salt reactor technology developed at ORNL, the MW beam accelerator technologies developed by basic sciences, and a reactor/target design optimized for accelerator driven-systems. The results include: the ability to use LWR spent fuel without reprocessing or additional waste; the ability to use natural uranium; no critical mass ever present; orders-of-magnitude less volatile radioactivity in the core; more efficient use of, and deeper

  20. GEnomes Management Application (GEM.app): a new software tool for large-scale collaborative genome analysis.

    Science.gov (United States)

    Gonzalez, Michael A; Lebrigio, Rafael F Acosta; Van Booven, Derek; Ulloa, Rick H; Powell, Eric; Speziani, Fiorella; Tekin, Mustafa; Schüle, Rebecca; Züchner, Stephan

    2013-06-01

    Novel genes are now identified at a rapid pace for many Mendelian disorders, and increasingly, for genetically complex phenotypes. However, new challenges have also become evident: (1) effectively managing larger exome and/or genome datasets, especially for smaller labs; (2) direct hands-on analysis and contextual interpretation of variant data in large genomic datasets; and (3) many small and medium-sized clinical and research-based investigative teams around the world are generating data that, if combined and shared, will significantly increase the opportunities for the entire community to identify new genes. To address these challenges, we have developed GEnomes Management Application (GEM.app), a software tool to annotate, manage, visualize, and analyze large genomic datasets (https://genomics.med.miami.edu/). GEM.app currently contains ∼1,600 whole exomes from 50 different phenotypes studied by 40 principal investigators from 15 different countries. The focus of GEM.app is on user-friendly analysis for nonbioinformaticians to make next-generation sequencing data directly accessible. Yet, GEM.app provides powerful and flexible filter options, including single family filtering, across family/phenotype queries, nested filtering, and evaluation of segregation in families. In addition, the system is fast, obtaining results within 4 sec across ∼1,200 exomes. We believe that this system will further enhance identification of genetic causes of human disease. © 2013 Wiley Periodicals, Inc.

  1. Modeling cellular systems

    CERN Document Server

    Matthäus, Franziska; Pahle, Jürgen

    2017-01-01

    This contributed volume comprises research articles and reviews on topics connected to the mathematical modeling of cellular systems. These contributions cover signaling pathways, stochastic effects, cell motility and mechanics, pattern formation processes, as well as multi-scale approaches. All authors attended the workshop on "Modeling Cellular Systems" which took place in Heidelberg in October 2014. The target audience primarily comprises researchers and experts in the field, but the book may also be beneficial for graduate students.

  2. For fashion and health (coloring of gems)

    International Nuclear Information System (INIS)

    Umeda, Iwao

    1998-01-01

    Artificial coloration of colorless jewel grade diamonds can be made by fast neutron irradiation using a research reactor or high energy electron beam bombardment by a linear accelerator. The irradiated color diamonds are from blue to green. After irradiation, the blue-green diamonds change color to yellow or orange by subsequent annealing using an electric furnace. The colored diamond hue depends on the treatment conditions. Fancy hue can be produced under some suitable conditions. Some special absorption bands in the spectrum obtained by a spectrophotometer can discriminate artificially colored diamonds from natural fancy color diamonds. Diamonds become to be radioactive immediately after irradiation by a reactor, but the radioactivity decay rapidly and become safe after a month. Some imported gems without diamond as blue topaz etc. are sometimes discovered to be radioactive artificially. Cultured pearls are covered by 0.4 mm thick nacreous layer on the pearl nucleus made of fresh-water unionidae thick shell. White pearls turn color to silver by 60 Co γ-ray irradiation. The pearl nucleus contained Mn turns color to brown by irradiation and absorbs red light from reflection on the surface, whereas the nacreous layer is little color change by irradiation because of small quantity of Mn and remains the luster. White pearls turn beautiful blue-silver of like natural color pearls seemingly, by γ-ray irradiation in suitable solution. Cubic zirconia made from ZrO 2 is a man-made colorless crystal looked like a diamond. The crystals turn color to orange by irradiation. (J.P.N)

  3. Progress on The GEMS (Gravity Electro-Magnetism-Strong) Theory of Field Unification and Its Application to Space Problems

    International Nuclear Information System (INIS)

    Brandenburg, J. E.

    2008-01-01

    Progress on the GEMS (Gravity Electro-Magnetism-Strong), theory is presented as well as its application to space problems. The GEMS theory is now validated through the Standard Model of physics. Derivation of the value of the Gravitation constant based on the observed variation of α with energy: results in the formula G congruent with (ℎ/2π)c/M ηc 2 exp(-1/(1.61α)), where α is the fine structure constant,(ℎ/2π), is Planck's constant, c, is the speed of light, and M ηc is the mass of the η cc Charmonium meson that is shown to be identical to that derived from the GEM postulates. Covariant formulation of the GEM theory is now possible through definition of the spacetime metric tensor as a portion of the EM stress tensor normalized by its own trace: g ab = 4(F c a F cb )/(F ab F ab ), it is found that this results in a massless ground state vacuum and a Newtonian gravitation potential φ = 1/2 E 2 /B 2 . It is also found that a Lorentz or flat-space metric is recovered in the limit of a full spectrum ZPF

  4. Modelling of wastewater systems

    DEFF Research Database (Denmark)

    Bechmann, Henrik

    Oxygen Demand) flux and SS flux in the inlet to the WWTP. COD is measured by means of a UV absorption sensor while SS is measured by a turbidity sensor. These models include a description of the deposit of COD and SS amounts, respectively, in the sewer system, and the models can thus be used to quantify......In this thesis, models of pollution fluxes in the inlet to 2 Danish wastewater treatment plants (WWTPs) as well as of suspended solids (SS) concentrations in the aeration tanks of an alternating WWTP and in the effluent from the aeration tanks are developed. The latter model is furthermore used...... to analyze and quantify the effect of the Aeration Tank Settling (ATS) operating mode, which is used during rain events. Furthermore, the model is used to propose a control algorithm for the phase lengths during ATS operation. The models are mainly formulated as state space model in continuous time...

  5. ISC-GEM: Global Instrumental Earthquake Catalogue (1900-2009), II. Location and seismicity patterns

    Science.gov (United States)

    Bondár, I.; Engdahl, E. Robert; Villaseñor, A.; Harris, James; Storchak, D.

    2015-02-01

    We present the final results of a two-year project sponsored by the Global Earthquake Model (GEM) Foundation. The ISC-GEM global catalogue consists of some 19 thousand instrumentally recorded, moderate to large earthquakes, spanning 110 years of seismicity. We relocated all events in the catalogue using a two-tier approach. The EHB location methodology (Engdahl et al., 1998) was applied first to obtain improved hypocentres with special focus on the depth determination. The locations were further refined in the next step by fixing the depths to those from the EHB analysis and applying the new International Seismological Centre (ISC) location algorithm (Bondár and Storchak, 2011) that reduces location bias by accounting for correlated travel-time prediction error structure. To facilitate the relocation effort, some one million seismic P and S wave arrival-time data were added to the ISC database for the period between 1904 and 1970, either from original station bulletins in the ISC archive or by digitizing the scanned images of the International Seismological Summary (ISS) bulletin (Villaseñor and Engdahl, 2005, 2007). Although no substantial amount of new phase data were acquired for the modern period (1964-2009), the number of phases used in the location has still increased by three millions, owing to fact that both the EHB and ISC locators use most well-recorded ak135 (Kennett et al., 1995) phases in the location. We show that the relocation effort yielded substantially improved locations, especially in the first half of the 20th century; we demonstrate significant improvements in focal depth estimates in subduction zones and other seismically active regions; and we show that the ISC-GEM catalogue provides an improved view of 110 years of global seismicity of the Earth. The ISC-GEM Global Instrumental Earthquake Catalogue represents the final product of one of the ten global components in the GEM program, and is available to researchers at the ISC (http://www.isc.ac.uk).

  6. GEMs with Double Layred Micropattern Electrodes and their Applications

    CERN Document Server

    Di Mauro, A.; Nappi, E.; Oliveira, R.; Peskov, V.; Pietropaolo, F.; Picchi, P.

    We have developed and tested several new designs of GEM detectors with micropattern electrodes manufactured by microelectronic technology. In one design, the inner layer of the detector electrode consists of thin metallic strips and the outer layer is made of a resistive grid manufactured by a screen printing technology. In other designs, the electrodes were made of metallic strips fed by HV via micro-resistors manufactured by a screen printing technology. Due to these features, the new detectors have several important advantages over conventional GEMs or ordinary thick GEMs. For example, the resistive grid (in the first design) and the screen printed resistors (in other designs) limited the current in case of discharges, making these detectors intrinsically spark-protected. We will here describe our tests with the photosensitive versions of these detectors (coated with CsI layers) and the efforts of implementing them in several applications. In particular, we will focus on our activity towards the ALICE RICH...

  7. [Two Turkish manuscripts on gems (jauhar) and the treatment by means of gems].

    Science.gov (United States)

    Kutlar, F S

    2001-01-01

    Literary works of the genre called cevâhir-nâme or cevher-nâme are written in order to give information on how gems (cevher-jauhar) are formed, where they are found, their estimated values, how to distinguish them from the imitations, what their particular colours are and on their uses and harmful effects. These literary works are sometimes titled in accordance with the genre they belong to and sometimes they are given different titles. The literary works dealing with the subject of cevher are mostly written in prose and only a few of them are in verse. The Turkish versions of cevâhir-nâme texts started to be written in the 15th century. These texts, covering the earlier knowledge of medicine, give information on gems and perfumes; how they effect human health; and the way they should be used in medical treatment. Therefore, these texts should be discussed in relation with their place in the history of Turkish science. Two cevâhir-nâmes, which were translated into Turkish by Mustafâ bin Seydî and Za'îfî in the 15th and 16th centuries are still available. The translations by Mustafâ bin Seydî and Za'îfî, did not only convey the classical and medieval knowledge on cevhers to the contemporary readers, but they also confirm the fact that this information was a part of the Ottoman social life.

  8. Modeling Complex Systems

    CERN Document Server

    Boccara, Nino

    2010-01-01

    Modeling Complex Systems, 2nd Edition, explores the process of modeling complex systems, providing examples from such diverse fields as ecology, epidemiology, sociology, seismology, and economics. It illustrates how models of complex systems are built and provides indispensable mathematical tools for studying their dynamics. This vital introductory text is useful for advanced undergraduate students in various scientific disciplines, and serves as an important reference book for graduate students and young researchers. This enhanced second edition includes: . -recent research results and bibliographic references -extra footnotes which provide biographical information on cited scientists who have made significant contributions to the field -new and improved worked-out examples to aid a student’s comprehension of the content -exercises to challenge the reader and complement the material Nino Boccara is also the author of Essentials of Mathematica: With Applications to Mathematics and Physics (Springer, 2007).

  9. Synthesis and Biological Evaluation of Glycosidase Inhibitors: gem-Difluoromethylenated Nojirimycin Analogues

    DEFF Research Database (Denmark)

    Bols, Mikael; Wang, Ruo-Wen; Qiu, Xiao-Long

    2006-01-01

    In our ongoing program aimed at the design, synthesis, and biological evaluation of novel gem-difluoromethylenated glycosidase inhibitors, gem-4,4-difluoromethylenated iminosugars (5-9) were synthesized. The biological evaluation of these synthetic iminosugars showed that the gem...

  10. Modeling Complex Systems

    International Nuclear Information System (INIS)

    Schreckenberg, M

    2004-01-01

    This book by Nino Boccara presents a compilation of model systems commonly termed as 'complex'. It starts with a definition of the systems under consideration and how to build up a model to describe the complex dynamics. The subsequent chapters are devoted to various categories of mean-field type models (differential and recurrence equations, chaos) and of agent-based models (cellular automata, networks and power-law distributions). Each chapter is supplemented by a number of exercises and their solutions. The table of contents looks a little arbitrary but the author took the most prominent model systems investigated over the years (and up until now there has been no unified theory covering the various aspects of complex dynamics). The model systems are explained by looking at a number of applications in various fields. The book is written as a textbook for interested students as well as serving as a comprehensive reference for experts. It is an ideal source for topics to be presented in a lecture on dynamics of complex systems. This is the first book on this 'wide' topic and I have long awaited such a book (in fact I planned to write it myself but this is much better than I could ever have written it!). Only section 6 on cellular automata is a little too limited to the author's point of view and one would have expected more about the famous Domany-Kinzel model (and more accurate citation!). In my opinion this is one of the best textbooks published during the last decade and even experts can learn a lot from it. Hopefully there will be an actualization after, say, five years since this field is growing so quickly. The price is too high for students but this, unfortunately, is the normal case today. Nevertheless I think it will be a great success! (book review)

  11. Modeling the earth system

    Energy Technology Data Exchange (ETDEWEB)

    Ojima, D. [ed.

    1992-12-31

    The 1990 Global Change Institute (GCI) on Earth System Modeling is the third of a series organized by the Office for Interdisciplinary Earth Studies to look in depth at particular issues critical to developing a better understanding of the earth system. The 1990 GCI on Earth System Modeling was organized around three themes: defining critical gaps in the knowledge of the earth system, developing simplified working models, and validating comprehensive system models. This book is divided into three sections that reflect these themes. Each section begins with a set of background papers offering a brief tutorial on the subject, followed by working group reports developed during the institute. These reports summarize the joint ideas and recommendations of the participants and bring to bear the interdisciplinary perspective that imbued the institute. Since the conclusion of the 1990 Global Change Institute, research programs, nationally and internationally, have moved forward to implement a number of the recommendations made at the institute, and many of the participants have maintained collegial interactions to develop research projects addressing the needs identified during the two weeks in Snowmass.

  12. Future change of water vaiables from HadGEM2-AO simulation

    Science.gov (United States)

    Kim, Moon-Hyun; Kang, Hyun-Suk; Lee, Johan; Baek, Hee-Jeong; Cho, Chunho

    2013-04-01

    hydrology-atmosphere for water resource planning. Arora et al. (1999) and Oki and Sud (1998) developed a method for routing river flows through GCM grid cells. Accordingly, reliable forecasts are expected to help water managers and users with long lead time decisions, leading to greater water use efficiency and better risk management (Wang, 2012). SO, we analysed hydrological cycle and drought index from precipitation, evaporation, runoff, soil moisture, river outflow, and so on using atmosphere-ocean coupled model which called by HadGEM2-AO. Details and added information by this climate projection system about the future water cycle's change will be presented at the workshop. Acknowledgments: This research has been supported by project NIMR-2013-B-2 of the National Institute of Meteorological Research in Korea Meteorological Administration.

  13. GEM Foil Quality Assurance For The ALICE TPC Upgrade

    Science.gov (United States)

    Brücken, Erik; Hildén, Timo

    2018-02-01

    The ALICE (A Large Ion Collider Experiment) experiment at the Large Hadron Collider (LHC) at CERN is dedicated to heavy ion physics to explore the structure of strongly interacting matter. The Time Projection Chamber (TPC) of ALICE is a tracking detector located in the central region of the experiment. It offers excellent tracking capabilities as well as particle identification. After the second long shutdown (LS2) the LHC will run at substantially higher luminosities. To be able to increase the data acquisition rate by a factor of 100, the ALICE TPC experiment has to replace the Multi-Wire Proportional Chamber (MWPC) -based readout chambers. The MWPC are operated with gating grid that limits the rate to O(kHz). The new ReadOut Chamber (ROC) design is based on Gas Electron Multiplier (GEM) technology operating in continuous mode. The current GEM productions scheme foresees the production of more than 800 GEM foils of different types. To fulfill the requirements on the performance of the GEM TPC readout, necessitates thorough Quality Assurance (QA) measures. The QA scheme, developed by the ALICE collaboration, will be presented in detail.

  14. Some G Pólya Gems from Complex Analysis

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 19; Issue 4. Some G Polya Gems from Complex Analysis. Shobha Madan. General Article Volume 19 Issue 4 April 2014 pp 323-337 ... Author Affiliations. Shobha Madan1. Department of Mathematics Indian Institute of Technology Kanpur 208 016, India.

  15. Gems: Obiects of Aesthetic Beauty and Scientific Curiosity

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 10; Issue 12. Gems: Obiects of Aesthetic Beauty and Scientific Curiosity. A K Ramdas. Volume 10 Issue 12 December 2005 pp 39-41. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/010/12/0039-0041 ...

  16. Low-Cost PicoAmpere Meter for GEM detectors

    CERN Document Server

    Buhagiar, Karl

    2013-01-01

    Measurement of picoampere current was only possible using very expensive instrumentation. The objective of my project at CERN was to participate in the development and test of a very low-cost picoampere current measuring box for HV lines in GEM detectors.

  17. GEM Foil Quality Assurance For The ALICE TPC Upgrade

    Directory of Open Access Journals (Sweden)

    Brücken Erik

    2018-01-01

    Full Text Available The ALICE (A Large Ion Collider Experiment experiment at the Large Hadron Collider (LHC at CERN is dedicated to heavy ion physics to explore the structure of strongly interacting matter. The Time Projection Chamber (TPC of ALICE is a tracking detector located in the central region of the experiment. It offers excellent tracking capabilities as well as particle identification. After the second long shutdown (LS2 the LHC will run at substantially higher luminosities. To be able to increase the data acquisition rate by a factor of 100, the ALICE TPC experiment has to replace the Multi-Wire Proportional Chamber (MWPC –based readout chambers. The MWPC are operated with gating grid that limits the rate to O(kHz. The new ReadOut Chamber (ROC design is based on Gas Electron Multiplier (GEM technology operating in continuous mode. The current GEM productions scheme foresees the production of more than 800 GEM foils of different types. To fulfill the requirements on the performance of the GEM TPC readout, necessitates thorough Quality Assurance (QA measures. The QA scheme, developed by the ALICE collaboration, will be presented in detail.

  18. Hard assets : The return of rare diamonds and gems

    NARCIS (Netherlands)

    Renneboog, Luc; Spaenjers, Christophe; Grynberg, Roman; Mbayi, Letsema

    This note examines the investment performance of diamonds and other gems (sapphires, rubies, and emeralds) over the period 1999–2010, using a novel data set of auction transactions. Over our time frame, the annualized real USD returns for white and colored diamonds equaled 6.4% and 2.9%,

  19. The Gravity and Extreme Magnetism Small Explorer (GEMS)

    Science.gov (United States)

    Kallman, T. R.

    2011-01-01

    The Gravity and Extreme Magnetism Small Explorer (GEMS) was selected by NASA for flight in 2014 to make a sensitive search for X-ray polarization from a wide set of source classes, including stellar black holes, Seyfert galaxies and quasars, blazars, rotation and accretion-powered pulsars, magnetars, shell supernova remnants and pulsar wind nebulae. Among the primary scientific objectives are determining the effects of the spin of black holes and the geometry of supermassive black hole accretion, determining the configurations of the magnetic fields and the X-ray emission of magnetars, and determining the magnetic structure of the supernova shocks in which cosmic rays are accelerated. GEMS will observe 23 targets during a 16 month prime mission, in observations that will be able to reach predicted levels of polarization. The mission can be extended to provide a guest observer phase. The GEMS instrument has time projection chamber polarimeters with high 2-10 keV efficiency at the focus of thin foil mirrors. The 4.5 m focal length mirrors will be deployed on an extended boom. The spacecraft with the instrument is rotated with a period of about 10 minutes to enable measurement and correction of systematic errors. A small Bragg reflection soft X-ray experiment takes advantage of this rotation to obtain a measurement at 0.5 keV. The design of the GEMS instrument and the mission, the expected performance and the planned science program will be discussed.

  20. A triple GEM detector with two-dimensional readout

    International Nuclear Information System (INIS)

    Ziegler, M.; Sievers, P.; Straumann, U.

    2001-01-01

    For the LHCb experiment a micropattern gas detector has been proposed as a possible technology for the inner tracking. A prototype triple GEM detector was built for this purpose. Here, the performance of this detector in a hadronic beam is presented

  1. Hard Assets : The Returns on Rare Diamonds and Gems

    NARCIS (Netherlands)

    Renneboog, L.D.R.; Spaenjers, C.

    2011-01-01

    This paper examines the investment performance of diamonds and other gems (sapphires, rubies, and emeralds) over the period 1999-2010, using a novel data set of auction transactions. Between 1999 and 2010, the annualized real USD returns for white and colored diamonds equaled 6.4% and 2.9%,

  2. Quality of the spare triple-GEM detectors

    CERN Document Server

    Lenci, Rosario; Paoletti, Emiliano; Pasquali, Luigi; Pinci, Davide; Piscitelli, Carmelo; Poli Lener, Marco; Sciubba, Adalberto; Tskhadadze, Edisher

    2017-01-01

    Triple-GEM chambers equip the inner region of the M1 muon station. In order to provide spare detectors in case of problems in the operating ones, new chambers have been assembled at the Frascati National Laboratories of the INFN. This note summarizes the results of the quality tests performed at the end of the production procedure.

  3. Single Electron Detection in Quadruple-GEM Detector with Pad Readout

    Energy Technology Data Exchange (ETDEWEB)

    Va' vra, Jaroslav

    2001-03-07

    Using a system of four GEMs operating in tandem and coupled to pad readout, we have demonstrated the detection of single electrons in ethane at 1 bar. The paper presents measurements of single electron pulse height distributions, total gas gain measurement and calculation, pad-to-pad cross-talk, quenching capability, high rate capability, charging effects, etc. We describe the overall operational experience, including addition of a gaseous photocathode, TMAE, and compare it to the SLD CRID single-electron detector [1], which has been operational during the past decade.

  4. High voltage distribution scheme for large size GEM detector

    International Nuclear Information System (INIS)

    Saini, J.; Kumar, A.; Dubey, A.K.; Negi, V.S.; Chattopadhyay, S.

    2016-01-01

    Gas Electron Multiplier (GEM) detectors will be used for Muon tracking in the Compressed Baryonic Matter (CBM) experiment at the Facility for Anti-proton Ion Research (FAIR) at Darmstadt, Germany. The sizes of the detector modules in the Muon chambers are of the order of 1 metre x 0.5 metre. For construction of these chambers, three GEM foils are used per chamber. These foils are made by two layered 50μm thin kapton foil. Each GEM foil has millions of holes on it. In such a large scale manufacturing of the foils, even after stringent quality controls, some of the holes may still have defects or defects might develop over the time with operating conditions. These defects may result in short-circuit of the entire GEM foil. A short even in a single hole will make entire foil un-usable. To reduce such occurrences, high voltage (HV) segmentation within the foils has been introduced. These segments are powered either by individual HV supply per segment or through an active HV distribution to manage such a large number of segments across the foil. Individual supplies apart from being costly, are highly complex to implement. Additionally, CBM will have high intensity of particles bombarding on the detector causing the change of resistive chain current feeding the GEM detector with the variation in the intensity. This leads to voltage fluctuations across the foil resulting in the gain variation with the particle intensity. Hence, a low cost active HV distribution is designed to take care of the above discussed issues

  5. Identifying anti-growth factors for human cancer cell lines through genome-scale metabolic modeling

    DEFF Research Database (Denmark)

    Ghaffari, Pouyan; Mardinoglu, Adil; Asplund, Anna

    2015-01-01

    Human cancer cell lines are used as important model systems to study molecular mechanisms associated with tumor growth, hereunder how genomic and biological heterogeneity found in primary tumors affect cellular phenotypes. We reconstructed Genome scale metabolic models (GEMs) for eleven cell lines...... based on RNA-Seq data and validated the functionality of these models with data from metabolite profiling. We used cell line-specific GEMs to analyze the differences in the metabolism of cancer cell lines, and to explore the heterogeneous expression of the metabolic subsystems. Furthermore, we predicted...... for inhibition of cell growth may provide leads for the development of efficient cancer treatment strategies....

  6. Information Systems Efficiency Model

    Directory of Open Access Journals (Sweden)

    Milos Koch

    2017-07-01

    Full Text Available This contribution discusses the basic concept of creating a new model for the efficiency and effectiveness assessment of company information systems. The present trends in this field are taken into account, and the attributes are retained of measuring the optimal solutions for a company’s ICT (the implementation, functionality, service, innovations, safety, relationships, costs, etc.. The proposal of a new model of assessment comes from our experience with formerly implemented and employed methods, methods which we have modified in time and adapted to companies’ needs but also to the necessaries of our research that has been done through the ZEFIS portal. The most noteworthy of them is the HOS method that we have discussed in a number of forums. Its main feature is the fact that it respects the complexity of an information system in correlation with the balanced state of its individual parts.

  7. Analysis of GEM properties and development of a GEM support structure for the ILD time projection chamber

    Energy Technology Data Exchange (ETDEWEB)

    Hallermann, Lea

    2010-04-15

    In the concept of the International Large Detector (ILD), developed for the International Linear Collider (ILC) a Time Projection Chamber (TPC) is envisaged as main tracking detector. Such gaseous detectors have to be equipped with amplification devices in order to enlarge the amount of charge, which is set free by ionization caused by traversing charged particles. Micro Pattern Gas Detectors (MPGDs) will be used in the ILD TPC as amplification stage. In this thesis, Gas Electron Multipliers (GEMs) - one specific MPGD species - are analyzed concerning various properties. Effective gains and energy resolutions are compared for GEM foils produced by different manufacturers. A good understanding of these observables is obtained by interpretation of the results with the help of geometrical parameters. Height profile measurements of GEM foils have been performed for the first time and the impact of non perfect flat GEMs is analyzed, especially on dE/dx determination and drift field quality. The results emphasize the need of a flat installation of GEMs in TPCs. As a consequence, a new mounting device has been developed to ensure flatness and to provide a method to cover large readout areas, as in the ILD TPC, by introducing the least possible amount of dead material into the detector. The developed structure has been tested in a TPC protoype, taking cosmic muon data. The influence of the mounting on track reconstruction, single point resolution, tracking efficiency and dE/dx measurements is quantified. The developed mounting is applicable in a large scale TPC, if some design considerations are taken into account. (orig.)

  8. Analysis of GEM properties and development of a GEM support structure for the ILD time projection chamber

    International Nuclear Information System (INIS)

    Hallermann, Lea

    2010-04-01

    In the concept of the International Large Detector (ILD), developed for the International Linear Collider (ILC) a Time Projection Chamber (TPC) is envisaged as main tracking detector. Such gaseous detectors have to be equipped with amplification devices in order to enlarge the amount of charge, which is set free by ionization caused by traversing charged particles. Micro Pattern Gas Detectors (MPGDs) will be used in the ILD TPC as amplification stage. In this thesis, Gas Electron Multipliers (GEMs) - one specific MPGD species - are analyzed concerning various properties. Effective gains and energy resolutions are compared for GEM foils produced by different manufacturers. A good understanding of these observables is obtained by interpretation of the results with the help of geometrical parameters. Height profile measurements of GEM foils have been performed for the first time and the impact of non perfect flat GEMs is analyzed, especially on dE/dx determination and drift field quality. The results emphasize the need of a flat installation of GEMs in TPCs. As a consequence, a new mounting device has been developed to ensure flatness and to provide a method to cover large readout areas, as in the ILD TPC, by introducing the least possible amount of dead material into the detector. The developed structure has been tested in a TPC protoype, taking cosmic muon data. The influence of the mounting on track reconstruction, single point resolution, tracking efficiency and dE/dx measurements is quantified. The developed mounting is applicable in a large scale TPC, if some design considerations are taken into account. (orig.)

  9. Depth of Response in Multiple Myeloma: A Pooled Analysis of Three PETHEMA/GEM Clinical Trials.

    Science.gov (United States)

    Lahuerta, Juan-Jose; Paiva, Bruno; Vidriales, Maria-Belen; Cordón, Lourdes; Cedena, Maria-Teresa; Puig, Noemi; Martinez-Lopez, Joaquin; Rosiñol, Laura; Gutierrez, Norma C; Martín-Ramos, María-Luisa; Oriol, Albert; Teruel, Ana-Isabel; Echeveste, María-Asunción; de Paz, Raquel; de Arriba, Felipe; Hernandez, Miguel T; Palomera, Luis; Martinez, Rafael; Martin, Alejandro; Alegre, Adrian; De la Rubia, Javier; Orfao, Alberto; Mateos, María-Victoria; Blade, Joan; San-Miguel, Jesus F

    2017-09-01

    Purpose To perform a critical analysis on the impact of depth of response in newly diagnosed multiple myeloma (MM). Patients and Methods Data were analyzed from 609 patients who were enrolled in the GEM (Grupo Español de Mieloma) 2000 and GEM2005MENOS65 studies for transplant-eligible MM and the GEM2010MAS65 clinical trial for elderly patients with MM who had minimal residual disease (MRD) assessments 9 months after study enrollment. Median follow-up of the series was 71 months. Results Achievement of complete remission (CR) in the absence of MRD negativity was not associated with prolonged progression-free survival (PFS) and overall survival (OS) compared with near-CR or partial response (median PFS, 27, 27, and 29 months, respectively; median OS, 59, 64, and 65 months, respectively). MRD-negative status was strongly associated with prolonged PFS (median, 63 months; P < .001) and OS (median not reached; P < .001) overall and in subgroups defined by prior transplantation, disease stage, and cytogenetics, with prognostic superiority of MRD negativity versus CR particularly evident in patients with high-risk cytogenetics. Accordingly, Harrell C statistics showed higher discrimination for both PFS and OS in Cox models that included MRD (as opposed to CR) for response assessment. Superior MRD-negative rates after different induction regimens anticipated prolonged PFS. Among 34 MRD-negative patients with MM and a phenotypic pattern of bone marrow involvement similar to monoclonal gammopathy of undetermined significance at diagnosis, the probability of "operational cure" was high; median PFS was 12 years, and the 10-year OS rate was 94%. Conclusion Our results demonstrate that MRD-negative status surpasses the prognostic value of CR achievement for PFS and OS across the disease spectrum, regardless of the type of treatment or patient risk group. MRD negativity should be considered as one of the most relevant end points for transplant-eligible and elderly fit patients

  10. The Shape of Long Outbursts in U Gem Type Dwarf Novae from AAVSO Data

    Science.gov (United States)

    Cannizzo, John K.

    2012-01-01

    We search the American Association of Variable Star Observers (AAVSO) archives of the two best studied dwarf novae in an attempt to find light curves for long out bursts that are extremely well-characterized. The systems are U Gem and S8 Cyg. Our goal is to search for embedded precursors such as those that have been found recently in the high fidelity Kepler data for superoutbursts of some members of the 8U UMa subclass of dwarf novae. For the vast majority of AAV80 data, the combination of low data cadence and large errors associated with individual measurements precludes one from making any strong statement about the shape of the long outbursts. However, for a small number of outbursts, extensive long term monitoring with digital photometry yields high fidelity light curves. We report the finding of embedded precursors in two of three candidate long outbursts. This reinforces van Paradijs' finding that long outbursts in dwarf novae above the period gap and superoutbursts in systems below the period gap constitute a unified class. The thermal-tidal instability to account for superoutbursts in the SU UMa stars predicts embedded precursors only for short orbital period dwarf novae, therefore the presence of embedded precursors in long orbital period systems - U Gem and SS Cyg - argues for a more general mechanism to explain long outbursts.

  11. Methods and results for calibration and track separation of a GEM based TPC using an UV-laser

    Energy Technology Data Exchange (ETDEWEB)

    Ball, Markus

    2008-12-15

    In the last 30 years high energy physics could write an impressive story of success. Since the introduction of the Standard Model (SM), it has met every experimental test. However the final confirmation has to prove the mechanism of electroweak symmetry breaking, which could not be confirmed yet. The most favored theory, which includes the introduction of a Higgs field, could not be verified experimentally. Furthermore there is clear evidence, that the SM is only a low energy description of nature and its principles, as the SM describes only 4 % of the known matter in the universe. There are two different approaches in accelerator driven high energy physics to clarify the open questions. The Large Hadron Collider (LHC) have a good opportunity to measure some of the missing pieces with its high center of mass energy. The International Linear Collider (ILC) will then measure their parameters with high precision. To guarantee this high precision the detectors have to be able to identify every single particle and determine its properties with high accuracy. These high requirements to the single detectors as well as the interconnectivity between all detectors are summarised by the concept of particle flow (PFLOW). This means that all particles must be separable, which includes in particular the main tracking device. A possible candidate for the central tracking device is a Time Projection Chamber (TPC). In this work a TPC with Gas Electron Multipliers (GEM) as gas amplification system was used. The GEMs replace the conventional wire amplification system of the TPC. In this PhD work a method to determine the drift velocity of a TPC was developed and tested using an ultraviolet laser. To ensure a high accuracy of the method all relevant gas parameters were measured with a slow control system. Furthermore the laser was used to investigate the separation capability of nearby tracks. Therefore an existing TPC prototype, which was developed to operate in a 5 T magnet facility

  12. Methods and results for calibration and track separation of a GEM based TPC using an UV-laser

    International Nuclear Information System (INIS)

    Ball, Markus

    2008-12-01

    In the last 30 years high energy physics could write an impressive story of success. Since the introduction of the Standard Model (SM), it has met every experimental test. However the final confirmation has to prove the mechanism of electroweak symmetry breaking, which could not be confirmed yet. The most favored theory, which includes the introduction of a Higgs field, could not be verified experimentally. Furthermore there is clear evidence, that the SM is only a low energy description of nature and its principles, as the SM describes only 4 % of the known matter in the universe. There are two different approaches in accelerator driven high energy physics to clarify the open questions. The Large Hadron Collider (LHC) have a good opportunity to measure some of the missing pieces with its high center of mass energy. The International Linear Collider (ILC) will then measure their parameters with high precision. To guarantee this high precision the detectors have to be able to identify every single particle and determine its properties with high accuracy. These high requirements to the single detectors as well as the interconnectivity between all detectors are summarised by the concept of particle flow (PFLOW). This means that all particles must be separable, which includes in particular the main tracking device. A possible candidate for the central tracking device is a Time Projection Chamber (TPC). In this work a TPC with Gas Electron Multipliers (GEM) as gas amplification system was used. The GEMs replace the conventional wire amplification system of the TPC. In this PhD work a method to determine the drift velocity of a TPC was developed and tested using an ultraviolet laser. To ensure a high accuracy of the method all relevant gas parameters were measured with a slow control system. Furthermore the laser was used to investigate the separation capability of nearby tracks. Therefore an existing TPC prototype, which was developed to operate in a 5 T magnet facility

  13. Atmospheric gaseous elemental mercury (GEM) over a coastal/rural site downwind of East China: Temporal variation and long-range transport

    Science.gov (United States)

    Ci, Zhijia; Zhang, Xiaoshan; Wang, Zhangwei; Niu, Zhenchuan

    2011-05-01

    Although much attention has been paid to the mercury pollution in China, limited field studies have been conducted to explore the atmospheric behavior of mercury. To investigate the temporal variation and long-range transport of atmospheric gaseous elemental mercury (GEM or Hg(0)), the GEM measurements covering four different seasons were performed at a coastal/rural site of the Yellow Sea downwind of East China. Hourly mean concentrations of GEM measured by RA-915+ mercury analyzer over the entire study (four different time periods between July 2007 and May 2009) were 2.31 ± 0.74 ng m -3 with a range of 1.12-7.01 ng m -3. The results showed moderate seasonal variations with high levels in cold seasons (winter: 2.53 ± 0.77 ng m -3 and spring: 2.34 ± 0.54 ng m -3) and low levels in warm seasons (summer: 2.28 ± 0.82 ng m -3 and fall: 2.16 ± 0.84 ng m -3). Over the each campaign a diurnal variation of GEM was observed consistently with peak levels in daytime and low levels in late night and early morning. The pollution rose and NOAA-HYSPLIT back-trajectory model analyses indicated that the elevated GEM was transported to the sampling site from the regional sources of East China and Korea peninsula-Japan. Air masses originated from the East China Sea and the regions of Continental East Asia with low emission strengths of atmospheric mercury (e.g., the east Russia, the north Inner Mongolia and the Bohai Sea) showed the decreased GEM levels.

  14. GEM-based beam profile monitors for the antiproton decelerator

    CERN Document Server

    Duarte Pinto, S.; Ropelewski, L.; Spanggaard, J.; Tranquille, G.

    2012-01-01

    The new beam profile measurement for the Antiproton Decelerator (AD) at CERN is based on a single Gas Electron Multiplier (GEM) with a 2D readout structure. This detector is very light, ~0.4% X0, as required by the low energy of the antiprotons, 5.3 MeV. This overcomes the problems previously encountered with multi-wire proportional chambers (MWPC) for the same purpose, where beam interactions with the detector severely affect the obtained profiles. A prototype was installed and successfully tested in late 2010, with another five detectors now installed in the ASACUSA and AEGIS beam lines. We will provide a detailed description of the detector and discuss the results obtained. The success of these detectors in the AD makes GEM-based detectors likely candidates for upgrade of the beam profile monitors in all experimental areas at CERN. The various types of MWPC currently in use are aging and becoming increasingly difficult to maintain.

  15. Further developments of the gas electron multiplier (GEM)

    CERN Document Server

    Benlloch, J M; Capéans-Garrido, M; Gruwé, M; Hoch, M; Labbé, J C; Placci, Alfredo; Ropelewski, Leszek; Sauli, Fabio

    1998-01-01

    We describe the development and operation of the Gas Electron Multiplier, a thin insulating foil metal-clad on both sides and perforated by a regular pattern of small holes. The mesh can be incorporat ed in the gas volume of an active detector to provide a first amplification channel for electrons, or used as stand alone. We report on the basic properties of GEMs manufactured with different geometr ies and operated in several gas mixtures as well as on their long-term stability after accumulation of charge equivalent to several years of operation in high luminosity experiments. Optimized GEMs re ach gains close to 10000 at safe operating voltages, permitting the detection of ionizing tracks, without other amplifying elements, on a simple printed circuit board (PCB), opening new possibilities for detector design.

  16. GEMS: Underwater spectrometer for long-term radioactivity measurements

    Energy Technology Data Exchange (ETDEWEB)

    Sartini, Ludovica, E-mail: ludovica.sartini@ingv.i [Istituto Nazionale di Geofisica e Vulcanologia (INGV), Sect.Roma 2, Roma (Italy); Genoa University, Genoa (Italy); Simeone, Francesco; Pani, Priscilla [' Sapienza' University and Istituto Nazionale di Fisica Nucleare (INFN), Sect.Roma, Roma (Italy); Lo Bue, Nadia; Marinaro, Giuditta [Istituto Nazionale di Geofisica e Vulcanologia (INGV), Sect.Roma 2, Roma (Italy); Grubich, Andry; Lobko, Alexander [Institute for Nuclear Problems (INP), Belarus State University, Minsk (Belarus); Etiope, Giuseppe [Istituto Nazionale di Geofisica e Vulcanologia (INGV), Sect.Roma 2, Roma (Italy); Capone, Antonio [' Sapienza' University and Istituto Nazionale di Fisica Nucleare (INFN), Sect.Roma, Roma (Italy); Favali, Paolo [Istituto Nazionale di Geofisica e Vulcanologia (INGV), Sect.Roma 2, Roma (Italy); Gasparoni, Francesco; Bruni, Federico [Tecnomare S.p.A., Venice (Italy)

    2011-01-21

    GEMS (Gamma Energy Marine Spectrometer) is a prototype of an autonomous radioactivity sensor for underwater measurements, developed in the framework for a development of a submarine telescope for neutrino detection (KM3NeT Design Study Project). The spectrometer is highly sensitive to gamma rays produced by {sup 40}K decays but it can detect other natural (e.g., {sup 238}U,{sup 232}Th) and anthropogenic radio-nuclides (e.g., {sup 137}Cs). GEMS was firstly tested and calibrated in the laboratory using known sources and it was successfully deployed for a long-term (6 months) monitoring at a depth of 3200 m in the Ionian Sea (Capo Passero, offshore Eastern Sicily). The instrument recorded data for the whole deployment period within the expected specifications. This monitoring provided, for the first time, a continuous time-series of radioactivity in deep-sea.

  17. Serial data acquisition for GEM-2D detector

    International Nuclear Information System (INIS)

    Kolasinski, Piotr; Pozniak, Krzysztof T.; Czarski, Tomasz; Linczuk, Maciej; Byszuk, Adrian; Chernyshova, Maryna; Juszczyk, Bartlomiej; Kasprowicz, Grzegorz; Wojenski, Andrzej; Zabolotny, Wojciech; Zienkiewicz, Pawel; Mazon, Didier; Malard, Philippe; Herrmann, Albrecht; Vezinet, Didier

    2014-01-01

    This article debates about data fast acquisition and histogramming method for the X-ray GEM detector. The whole process of histogramming is performed by FPGA chips (Spartan-6 series from Xilinx). The results of the histogramming process are stored in an internal FPGA memory and then sent to PC. In PC data is merged and processed by MATLAB. The structure of firmware functionality implemented in the FPGAs is described. Examples of test measurements and results are presented. (authors)

  18. Serial data acquisition for GEM-2D detector

    Science.gov (United States)

    Kolasinski, Piotr; Pozniak, Krzysztof T.; Czarski, Tomasz; Linczuk, Maciej; Byszuk, Adrian; Chernyshova, Maryna; Juszczyk, Bartlomiej; Kasprowicz, Grzegorz; Wojenski, Andrzej; Zabolotny, Wojciech; Zienkiewicz, Pawel; Mazon, Didier; Malard, Philippe; Herrmann, Albrecht; Vezinet, Didier

    2014-11-01

    This article debates about data fast acquisition and histogramming method for the X-ray GEM detector. The whole process of histogramming is performed by FPGA chips (Spartan-6 series from Xilinx). The results of the histogramming process are stored in an internal FPGA memory and then sent to PC. In PC data is merged and processed by MATLAB. The structure of firmware functionality implemented in the FPGAs is described. Examples of test measurements and results are presented.

  19. The TOTEM GEM Telescope (T2) at the LHC

    International Nuclear Information System (INIS)

    Quinto, M.; Berretti, M.; David, E.; Garcia, F.; Greco, V.; Heino, J.; Hilden, T.; Kurvinen, K.; Lami, S.; Latino, G.; Lauhakangas, R.; Oliveri, E.; Ropelewski, L.; Scribano, A.; Turini, N.; Stenis, M. van

    2011-01-01

    The TOTEM T2 telescope will measure inelastically produced charged particles in the forward region of the LHC Interaction Point 5. Each arm of the telescope consists in a set of 20 triple-GEM (Gas Electron Multiplier) detectors with tracking and trigger capabilities. The GEM technology has been considered for the design of TOTEM very forward T2 telescopes thanks to its characteristics: large active areas, good position and timing resolution, excellent rate capability and radiation hardness. Each of the four T2 half arms has been fully assembled and equipped with electronics at CERN and systematically tested in the SPS beam line H8 in 2008/09. After some optimization, the operation of the GEM chambers was fully satisfactory and the T2 telescopes were installed and commissioned in their final positions at the LHC interaction point. During the first LHC run (December 2009) the T2 telescopes have collected data, at 900 GeV and 2.36 TeV. We will present here the performances of the detector and the preliminary results obtained using the data collected.

  20. The TOTEM GEM Telescope (T2) at the LHC

    Energy Technology Data Exchange (ETDEWEB)

    Quinto, M. [INFN Sezione di Bari, Via E.Orabona n 4, 70126 Bari (Italy); Berretti, M. [University of Siena, Physics Department, Via Roma 56, I-53100 Siena (Italy); INFN Sezione di Pisa, Largo B. Pontecorvo, 3. I-56127. Pisa (Italy); David, E. [CERN, PH Department, 1211 Geneva 23, Geneva (Switzerland); Garcia, F. [University of Helsinki, Institute of Physics and Department of Physical Sciences, Helsinki (Finland); Greco, V. [University of Siena, Physics Department, Via Roma 56, I-53100 Siena (Italy); INFN Sezione di Pisa, Largo B. Pontecorvo, 3. I-56127. Pisa (Italy); Heino, J.; Hilden, T.; Kurvinen, K. [University of Helsinki, Institute of Physics and Department of Physical Sciences, Helsinki (Finland); Lami, S. [INFN Sezione di Pisa, Largo B. Pontecorvo, 3. I-56127. Pisa (Italy); Latino, G. [University of Siena, Physics Department, Via Roma 56, I-53100 Siena (Italy); INFN Sezione di Pisa, Largo B. Pontecorvo, 3. I-56127. Pisa (Italy); Lauhakangas, R. [University of Helsinki, Institute of Physics and Department of Physical Sciences, Helsinki (Finland); Oliveri, E. [University of Siena, Physics Department, Via Roma 56, I-53100 Siena (Italy); INFN Sezione di Pisa, Largo B. Pontecorvo, 3. I-56127. Pisa (Italy); Ropelewski, L. [CERN, PH Department, 1211 Geneva 23, Geneva (Switzerland); Scribano, A.; Turini, N. [University of Siena, Physics Department, Via Roma 56, I-53100 Siena (Italy); INFN Sezione di Pisa, Largo B. Pontecorvo, 3. I-56127. Pisa (Italy); Stenis, M. van [CERN, PH Department, 1211 Geneva 23, Geneva (Switzerland)

    2011-06-15

    The TOTEM T2 telescope will measure inelastically produced charged particles in the forward region of the LHC Interaction Point 5. Each arm of the telescope consists in a set of 20 triple-GEM (Gas Electron Multiplier) detectors with tracking and trigger capabilities. The GEM technology has been considered for the design of TOTEM very forward T2 telescopes thanks to its characteristics: large active areas, good position and timing resolution, excellent rate capability and radiation hardness. Each of the four T2 half arms has been fully assembled and equipped with electronics at CERN and systematically tested in the SPS beam line H8 in 2008/09. After some optimization, the operation of the GEM chambers was fully satisfactory and the T2 telescopes were installed and commissioned in their final positions at the LHC interaction point. During the first LHC run (December 2009) the T2 telescopes have collected data, at 900 GeV and 2.36 TeV. We will present here the performances of the detector and the preliminary results obtained using the data collected.

  1. Study of relevant parameters of GEM-based detectors

    CERN Document Server

    Croci, Gabriele; Sauli, Fabio; Ragazzi, S

    2007-01-01

    The Gas Electron Multiplier consist of a thin Kapton insulating (50 $\\mu$m) foil copper-clad on both sides and perforated by a high density, regular matrix of holes (around 100 per square millimeter). Typically the distance between holes (pitch) is 140 $\\mu$m and diameters of about 70 $\\mu$m. The mesh is realised by conventional photolitographic methods as used for the fabrication of multi-layer board. Upon application of a potential difference between the GEM electrodes, a high dipole field develops in the holes focusing the field lines between the drift electrode and the readout element. Electron drift along the channel and the charge is amplified by a factor that depends on the field density and the length of the channel. Owing to their excellent position resolution and rate capability GEM-based detector are very suitable to be used in different applications: from the high energy physics to the medical field. The GEM temporal and rate gain stability was studied and it was discovered that the gain variation...

  2. Development of near infrared spectrometer for gem materials study

    Science.gov (United States)

    Jindata, W.; Meesiri, W.; Wongkokua, W.

    2015-07-01

    Most of gem materials can be characterized by infrared absorption spectroscopy. Normally, mid infrared absorption technique has been applied for investigating fundamental vibrational modes. However, for some gem materials, such as tourmaline, NIR is a better choice due to differentiation. Most commercial NIR spectrometers employ complicated dispersive grating or Fourier transform techniques. In this work, we developed a filter type NIR spectrometer with the availability of high efficiency and low-cost narrow bandpass NIR interference filters to be taught in a physics laboratory. The instrument was designed for transmission-mode configuration. A 50W halogen lamp was used as NIR source. There were fourteen NIR filters mounted on a rotatory wheel for wavelength selection ranging from 1000-1650 nm with steps of 50 nm. A 1.0 mm diameter of InGaAs photodiode was used as the detector for the spectrometer. Hence, transparent gem materials can be used as samples for experiment. Student can learn vibrational absorption spectroscopy as well as Beer-Lambert law from the development of this instrument.

  3. GEM operation in helium and neon at low temperatures

    Science.gov (United States)

    Buzulutskov, A.; Dodd, J.; Galea, R.; Ju, Y.; Leltchouk, M.; Rehak, P.; Tcherniatine, V.; Willis, W. J.; Bondar, A.; Pavlyuchenko, D.; Snopkov, R.; Tikhonov, Y.

    2005-08-01

    We study the performance of Gas Electron Multipliers (GEMs) in gaseous He, Ne and Ne+H 2 at temperatures in the range of 2.6-293 K. In He, at temperatures between 62 and 293 K, the triple-GEM structures often operate at rather high gains, exceeding 1000. There is an indication that this high gain is achieved by the Penning effect in the gas impurities released by outgassing. At lower temperatures, the gain-voltage characteristics are significantly modified probably due to the freeze-out of impurities. In particular, the double- and single-GEM structures can operate down to 2.6 K at gains reaching only several tens at a gas density of about 0.5 g/l; at higher densities the maximum gain drops further. In Ne, the maximum gain also drops at cryogenic temperatures. The gain drop in Ne at low temperatures can be reestablished in Penning mixtures of Ne+H 2: very high gains, exceeding 10 4, have been obtained in these mixtures at 50-60 K, at a density of 9.2 g/l corresponding to that of saturated Ne vapor near 27 K. The results obtained are relevant in the fields of two-phase He and Ne detectors for solar neutrino detection and electron avalanching at low temperatures.

  4. High-rate particle triggering with triple-GEM detector

    CERN Document Server

    Alfonsi, M; De Simone, P; Murtas, F; Poli-Lener, M; Bonivento, W; Cardini, A; Deplano, C; Raspino, D; Pinci, D

    2004-01-01

    We report the results of a systematic study of the time performance of triple-GEM detectors operated with Ar/CO//2/CF//4 and Ar/CF//4 /iso-C//4H//1//0 gas mixtures. This study and the detector development has been performed in the framework of an R&D activity on detectors for the innermost part (region R1) of the first muon station (M1) of the LHCb experiment. The use of fast gas mixtures allows to achieve a time resolution better than 5 ns (r.m.s.) and a single detector efficiency up to similar to 99% in a 20 ns time window. Discharge studies have been performed at the piM1 hadron beam facility of the Paul Scherrer Institute. Local aging properties were investigated exposing the detector to a collimated 5.9 keV X-rays beam. The whole R&D activity with different gas mixtures has been performed with small 10 multiplied by 10 cm**2 triple-GEM detector prototypes. A full size prototype (module-0) constituted by two 20 multiplied by 24 cm**2 triple-GEM detectors, equipped with front-end electronics based ...

  5. Investigation of the "Escalator Effect" in the Kilmore East Fire of February, 2009 using GEM-AQ

    Science.gov (United States)

    Beale, J. L.; Semeniuk, K.; Lupu, A.; Kaminski, J. W.; McConnell, J. C.; O'Neill, N. T.; Glatthor, N.; Höpfner, M.; Palmer, P. I.; Tost, H.

    2012-12-01

    In early February, 2009, Southeast Australia was swept by intense bush fires which burned an area of about 3000 km2. Combustion products such as C2H2, HCN and HCOOH were observed in the UTLS region a few days later by MIPAS on the ENVISAT satellite. In addition, the OSIRIS instrument on the ODIN spacecraft has attributed aerosol measurements to products of the burning and lifting while the MLS instrument on AURA measured high values of CO for several weeks after the fire. This study is a continuation of the study by Glatthor et al (2012) which compared MIPAS observations to a high-resolution model run of the Global Environmental Multiscale with Air Quality (GEM-AQ) model. There is generally good agreement between the modelling and the observations, but there is still uncertainty as to whether the lifting of material into the UTLS by the fire process can be considered pyroconvection, or if it is due to the diabatic heating and lifting of the aerosol produced in the burning process (the "escalator effect"), or both. One limitation of our earlier study was the injection process of burning species and the lack of radiatively and chemically active aerosols within GEM-AQ. In this study we add black carbon (BC) and organic carbon (OC) estimates as part of the burning process and assess their role in the lifting of the biomass-burning material. The work described here uses GEM version 3.3.2. The gas-phase chemistry consists of detailed reactions of Ox, NOx, HOx, CO, CH4, NMVOCs, halocarbons, ClOx and BrO. We have recently added elements of the Global Modal-aerosol eXtension (GMXe) scheme to address aerosol microphysics and gas-aerosol partitioning. GEM-AQ is a global general circulation model based on the GEM model developed by the Meteorological Service of Canada for operational weather forecasting with on-line air quality and chemistry. It can be run with a global variable (GV) grid where the core has uniform grid spacing and the exterior grid expands. Our simulations

  6. Ion space-charge effects in multi-GEM detectors: challenges and possible solutions for future applications

    CERN Document Server

    AUTHOR|(CDS)2079251; Streli, Christina

    Gaseous Electron Multiplier (GEM) detectors are well known both for stable operation under irradiation with high particle fluxes and high achievable effective gains. The aim of this thesis is two-fold: to investigate the limits of GEM detector operation due to space-charge effects, and to develop a means to reduce the magnitude of the observed effects and thus extend those limitations. The first part of the thesis presents a comprehensive study of the intrinsic limits of triple-GEM detectors under exposure to very high fluxes of soft X-rays or operation at very large effective gains. The behaviour of the effective gain, ion back-flow and the pulse-height spectra is explained in terms of the movement and accumulation of positive ions throughout the detector volume, resulting in distortions of the transfer and amplification fields. Numerical computations, and measurements on double-stage and single-stage detectors confirm the model describing the observed effects. Discussions on ways to extend the limits of gas...

  7. The current status of the Gas Electron Multiplier (GEM) research at Kasetsart University, Thailand

    Science.gov (United States)

    Kumpiranon, P.; Kulasri, K.; Rittirong, A.; Saenboonruang, K.

    2017-06-01

    During the past decade, Gas Electron Multiplier (GEM) detectors have been greatly developed and utilized in numbers of applications including advanced nuclear and particle researches, medical imaging, astrophysics, and neutron detection for national security. Our GEM research group at the Department of Applied Radiation and Isotopes, Faculty of Science, Kasetsart University, Thailand, realized in its excellent properties/potentials and started extensive researches on GEM detectors. To build a strong foundation on our research group, two 10 cm × 10 cm triple GEM detectors were characterized on their important properties including absolute gains and detection uniformity. Moreover, to widen applications of the GEM detector, our group had modified the GEM detector by introducing either solid or gaseous neutron converters to the detector so that the detector could effectively detect neutrons. These modifications included coating a thin film of 10B and natB to the GEM drift cathode for thermal neutron detection and flowing a gas mixture of He/CO2 (80:20 and 70:30) and C4H10/He/CO2 (7:70:23) for fast neutron detection. Results showed that the modified GEM-based neutron detector could detect both types of neutrons with different relative efficiencies and gains depending on thicknesses and types of neutron converters. This article discusses basic knowledge of the GEM detector, construction and testing procedures, results, and discussion.

  8. Statistical exploration of gaseous elemental mercury (GEM) measured at Cape Point from 2007 to 2011

    Science.gov (United States)

    Venter, A. D.; Beukes, J. P.; van Zyl, P. G.; Brunke, E.-G.; Labuschagne, C.; Slemr, F.; Ebinghaus, R.; Kock, H.

    2015-09-01

    The authors evaluated continuous high-resolution gaseous elemental mercury (GEM) data from the Cape Point Global Atmosphere Watch (CPT GAW) station with different statistical analysis techniques. GEM data were evaluated by cluster analysis and the results indicated that two clusters, separated at 0.904 ng m-3, existed. The air mass history for the two-cluster solution was investigated by means of back-trajectory analysis. The air mass back-trajectory net result showed lower GEM concentrations originating from the sparsely populated semi-arid interior of South Africa and the marine environment, whereas higher GEM concentrations originated predominately along the coast of South Africa that most likely coincide with trade routes and industrial activities in urban areas along the coast. Considering the net result from the air mass back-trajectories, it is evident that not all low GEM concentrations are from marine origin, and similarly, not all high GEM concentrations have a terrestrial origin. Equations were developed by means of multi-linear regression (MLR) analysis that allowed for the estimation and/or prediction of atmospheric GEM concentrations from other atmospheric parameters measured at the CPT GAW station. These equations also provided some insight into the relation and interaction of GEM with other atmospheric parameters. Both measured and MLR calculated data confirm a decline in GEM concentrations at CPT GAW over the period evaluated.

  9. Verification of High-Resolution Medium-Range Precipitation Forecasts from Global Environmental Multiscale Model over China during 2009–2013

    Directory of Open Access Journals (Sweden)

    Huating Xu

    2018-03-01

    Full Text Available Accurate and timely precipitation forecasts are a key factor for improving hydrological forecasts. Therefore, it is fundamental to evaluate the skill of Numerical Weather Prediction (NWP for precipitation forecasting. In this study, the Global Environmental Multi-scale (GEM model, which is widely used around Canada, was chosen as the high-resolution medium-term prediction model. Based on the forecast precipitation with the resolution of 0.24° and taking regional differences into consideration, the study explored the forecasting skill of GEM in nine drought sub-regions around China. Spatially, GEM performs better in East and South China than in the inland areas. Temporally, the model is able to produce more precise precipitation during flood periods (summer and autumn compared with the non-flood season (winter and spring. The forecasting skill variability differs with regions, lead time and season. For different precipitation categories, GEM for trace rainfall and little rainfall performs much better than moderate rainfall and above. Overall, compared with other prediction systems, GEM is applicable for the 0–96 h forecast, especially for the East and South China in flood season, but improvement for the prediction of heavy and storm rainfall and for the inland areas should be focused on as well.

  10. Modeling and estimating system availability

    International Nuclear Information System (INIS)

    Gaver, D.P.; Chu, B.B.

    1976-11-01

    Mathematical models to infer the availability of various types of more or less complicated systems are described. The analyses presented are probabilistic in nature and consist of three parts: a presentation of various analytic models for availability; a means of deriving approximate probability limits on system availability; and a means of statistical inference of system availability from sparse data, using a jackknife procedure. Various low-order redundant systems are used as examples, but extension to more complex systems is not difficult

  11. Resolution studies of a GEM-based TPC

    International Nuclear Information System (INIS)

    Killenberg, M.

    2006-01-01

    Currently there are four different concept studies trying to optimise the detector for the requirements at the ILC. In three of these detector concepts a time projection chamber (TPC) is foreseen as the main tracking device. To achieve the intended spatial resolution of 100 μm, micro pattern gas detectors (MPGD) are considered for gas amplification. The two different MPGDs discussed for the ILC TPC are Micro-Mesh Gaseous Detectors (Micromegas) and Gas Electron Multiplier foils (GEMs). The current thesis shows resolution studies with a TPC prototype equipped with a triple GEM readout structure. A hodoscope made up of silicon strip sensors gives a precision reference track, allowing an unbiased measurement of the spatial resolution. High statistics measurements have been conducted at the DESY test beam facility, which provides positrons with a tunable energy between 1 GeV and 6 GeV. Using the independent measurement of the hodoscope allows systematic studies of the homogeneity of the TPC's electric field. The fluctuations of the field in the chamber's central region were found to be ΔE/E=8.10 -3 . Field distortions have been determined and corrected, reducing the remaining deviations to a level well below the spatial resolution of the TPC. One important task is to reduce the number of ions drifting back into the sensitive volume. Special GEM settings with minimised ion backdrift have been examined with respect to their influence on the spatial resolution and it was found that the spatial resolution is not degraded using these special settings. The TPC prototype has been operated in a 4 T magnetic field, provided by a superconducting solenoid located at DESY Hamburg. Again the spatial resolution measured with the ion backdrift optimised settings is compared to that achieved with nonoptimised settings. In both cases the measured resolution is approximately 130 μm. (orig.)

  12. Resolution studies of a GEM-based TPC

    Energy Technology Data Exchange (ETDEWEB)

    Killenberg, M.

    2006-12-15

    Currently there are four different concept studies trying to optimise the detector for the requirements at the ILC. In three of these detector concepts a time projection chamber (TPC) is foreseen as the main tracking device. To achieve the intended spatial resolution of 100 {mu}m, micro pattern gas detectors (MPGD) are considered for gas amplification. The two different MPGDs discussed for the ILC TPC are Micro-Mesh Gaseous Detectors (Micromegas) and Gas Electron Multiplier foils (GEMs). The current thesis shows resolution studies with a TPC prototype equipped with a triple GEM readout structure. A hodoscope made up of silicon strip sensors gives a precision reference track, allowing an unbiased measurement of the spatial resolution. High statistics measurements have been conducted at the DESY test beam facility, which provides positrons with a tunable energy between 1 GeV and 6 GeV. Using the independent measurement of the hodoscope allows systematic studies of the homogeneity of the TPC's electric field. The fluctuations of the field in the chamber's central region were found to be {delta}E/E=8.10{sup -3}. Field distortions have been determined and corrected, reducing the remaining deviations to a level well below the spatial resolution of the TPC. One important task is to reduce the number of ions drifting back into the sensitive volume. Special GEM settings with minimised ion backdrift have been examined with respect to their influence on the spatial resolution and it was found that the spatial resolution is not degraded using these special settings. The TPC prototype has been operated in a 4 T magnetic field, provided by a superconducting solenoid located at DESY Hamburg. Again the spatial resolution measured with the ion backdrift optimised settings is compared to that achieved with nonoptimised settings. In both cases the measured resolution is approximately 130 {mu}m. (orig.)

  13. A new Slow Control and Run Initialization Byte-wise Environment (SCRIBE) for the quality control of mass-produced CMS GEM detectors

    CERN Document Server

    Colafranceschi, Stefano

    2016-01-01

    The CMS collaboration aims at improving the muon trigger and tracking performance at the HL-LHC by installing new Gas Electron Multiplier (GEM) detectors in the endcaps of the CMS experiment. Construction and commissioning of GEM detectors for the first muon endcap stations is ramping up in several laboratories using common quality control protocols. The SCRIBE framework is a scalable and cross-platform web-based application for the RD51 Scalable Readout System (SRS) that controls data acquisition and analyzes data in near real time. It has been developed mainly to simplify and standardize measurements of the GEM detector response uniformities with x-rays across all production sites. SCRIBE works with zero suppression of raw SRS pulse height data. This has increased acquisition rates to 5 kHz for a CMS GEM detector with 3072 strips and allows strip-by-strip response comparisons with a few hours of data taking. SCRIBE also manages parallel data reconstruction to provide near real-time feedback on the detector ...

  14. Modelling of reverberation enhancement systems

    OpenAIRE

    ROUCH , Jeremy; Schmich , Isabelle; Galland , Marie-Annick

    2012-01-01

    International audience; Electroacoustic enhancement systems are increasingly specified by acoustic consultants to address the requests for a multi-purpose use of performance halls. However, there is still a lack of simple models to predict the effect induced by these systems on the acoustic field. Two models are introduced to establish the impulse responses of a room equipped with a reverberation enhancement system. These models are based on passive impulse responses according to the modified...

  15. MODELLING OF MATERIAL FLOW SYSTEMS

    OpenAIRE

    PÉTER TELEK

    2012-01-01

    Material flow systems are in generally very complex processes. During design, building and operation of complex systems there are many different problems. If these complex processes can be described in a simple model, the tasks will be clearer, better adaptable and easier solvable. As the material flow systems are very different, so using models is a very important aid to create uniform methods and solutions. This paper shows the details of the application possibilities of modelling in the ma...

  16. Dynamic Modeling of ALS Systems

    Science.gov (United States)

    Jones, Harry

    2002-01-01

    The purpose of dynamic modeling and simulation of Advanced Life Support (ALS) systems is to help design them. Static steady state systems analysis provides basic information and is necessary to guide dynamic modeling, but static analysis is not sufficient to design and compare systems. ALS systems must respond to external input variations and internal off-nominal behavior. Buffer sizing, resupply scheduling, failure response, and control system design are aspects of dynamic system design. We develop two dynamic mass flow models and use them in simulations to evaluate systems issues, optimize designs, and make system design trades. One model is of nitrogen leakage in the space station, the other is of a waste processor failure in a regenerative life support system. Most systems analyses are concerned with optimizing the cost/benefit of a system at its nominal steady-state operating point. ALS analysis must go beyond the static steady state to include dynamic system design. All life support systems exhibit behavior that varies over time. ALS systems must respond to equipment operating cycles, repair schedules, and occasional off-nominal behavior or malfunctions. Biological components, such as bioreactors, composters, and food plant growth chambers, usually have operating cycles or other complex time behavior. Buffer sizes, material stocks, and resupply rates determine dynamic system behavior and directly affect system mass and cost. Dynamic simulation is needed to avoid the extremes of costly over-design of buffers and material reserves or system failure due to insufficient buffers and lack of stored material.

  17. Modeling soft interface dominated systems

    NARCIS (Netherlands)

    Lamorgese, A.; Mauri, R.; Sagis, L.M.C.

    2017-01-01

    The two main continuum frameworks used for modeling the dynamics of soft multiphase systems are the Gibbs dividing surface model, and the diffuse interface model. In the former the interface is modeled as a two dimensional surface, and excess properties such as a surface density, or surface energy

  18. Validation of systems biology models

    NARCIS (Netherlands)

    Hasdemir, D.

    2015-01-01

    The paradigm shift from qualitative to quantitative analysis of biological systems brought a substantial number of modeling approaches to the stage of molecular biology research. These include but certainly are not limited to nonlinear kinetic models, static network models and models obtained by the

  19. A time projection chamber with GEM-based readout

    Science.gov (United States)

    Attié, David; Behnke, Ties; Bellerive, Alain; Bezshyyko, Oleg; Bhattacharya, Deb Sankar; Bhattacharya, Purba; Bhattacharya, Sudeb; Caiazza, Stefano; Colas, Paul; Lentdecker, Gilles De; Dehmelt, Klaus; Desch, Klaus; Diener, Ralf; Dixit, Madhu; Fleck, Ivor; Fujii, Keisuke; Fusayasu, Takahiro; Ganjour, Serguei; Gao, Yuanning; Gros, Philippe; Hayman, Peter; Hedberg, Vincent; Ikematsu, Katsumasa; Jönsson, Leif; Kaminski, Jochen; Kato, Yukihiro; Kawada, Shin-ichi; Killenberg, Martin; Kleinwort, Claus; Kobayashi, Makoto; Krylov, Vladyslav; Li, Bo; Li, Yulan; Lundberg, Björn; Lupberger, Michael; Majumdar, Nayana; Matsuda, Takeshi; Mehdiyev, Rashid; Mjörnmark, Ulf; Müller, Felix; Münnich, Astrid; Mukhopadhyay, Supratik; Ogawa, Tomohisa; Oskarsson, Anders; Österman, Lennart; Peterson, Daniel; Riallot, Marc; Rosemann, Christoph; Roth, Stefan; Schade, Peter; Schäfer, Oliver; Settles, Ronald Dean; Shirazi, Amir Noori; Smirnova, Oxana; Sugiyama, Akira; Takahashi, Tohru; Tian, Junping; Timmermans, Jan; Titov, Maksym; Tsionou, Dimitra; Vauth, Annika; Wang, Wenxin; Watanabe, Takashi; Werthenbach, Ulrich; Yang, Yifan; Yang, Zhenwei; Yonamine, Ryo; Zenker, Klaus; Zhang, Fan

    2017-06-01

    For the International Large Detector concept at the planned International Linear Collider, the use of time projection chambers (TPC) with micro-pattern gas detector readout as the main tracking detector is investigated. In this paper, results from a prototype TPC, placed in a 1 T solenoidal field and read out with three independent Gas Electron Multiplier (GEM) based readout modules, are reported. The TPC was exposed to a 6 GeV electron beam at the DESY II synchrotron. The efficiency for reconstructing hits, the measurement of the drift velocity, the space point resolution and the control of field inhomogeneities are presented.

  20. Radiation imaging with glass gas electron multipliers (G -GEMs)

    Science.gov (United States)

    Fujiwara, Takeshi; Mitsuya, Yuki; Takahashi, Hiroyuki

    2018-01-01

    This review investigates the advantages and disadvantages of gaseous radiation detectors when compared with solid-state detectors, for use in radiation imaging, which are caused by the differing properties of gases and solids. Imaging applications for which micro-pattern gas detectors (MPGDs) are superior, include neutron imaging, high-linear-energy-transfer (LET) radiation imaging, and low-energy-depositing radiation imaging. This paper is focused on these applications where MPGDs, in particular, the glass gas electron multiplier (G-GEM), are superior, and their development is described and relevant experimental results are discussed.

  1. GEMS Project: A Platform to Investigate Multiple Sclerosis Risk

    Science.gov (United States)

    Xia, Zongqi; White, Charles C.; Owen, Emily K.; Von Korff, Alina; Clarkson, Sarah R.; McCabe, Cristin A.; Cimpean, Maria; Winn, Phoebe A.; Hoesing, Ashley; Steele, Sonya U.; Cortese, Irene C. M.; Chitnis, Tanuja; Weiner, Howard L.; Reich, Daniel S.; Chibnik, Lori B.; De Jager, Philip L.

    2015-01-01

    The Genes and Environment in Multiple Sclerosis (GEMS) project establishes a platform to investigate the events leading to MS in at-risk individuals. It has recruited 2,632 first-degree relatives from across the USA. Using an integrated genetic and environmental risk score, we identified subjects with twice the MS risk when compared to the average family member, and we report an initial incidence rate in these subjects that is 30 times greater than that of sporadic MS. We discuss the feasibility of large-scale studies of asymptomatic at-risk subjects that leverage modern tools of subject recruitment to execute collaborative projects. PMID:26583565

  2. From Numeric Models to Granular System Modeling

    Directory of Open Access Journals (Sweden)

    Witold Pedrycz

    2015-03-01

    To make this study self-contained, we briefly recall the key concepts of granular computing and demonstrate how this conceptual framework and its algorithmic fundamentals give rise to granular models. We discuss several representative formal setups used in describing and processing information granules including fuzzy sets, rough sets, and interval calculus. Key architectures of models dwell upon relationships among information granules. We demonstrate how information granularity and its optimization can be regarded as an important design asset to be exploited in system modeling and giving rise to granular models. With this regard, an important category of rule-based models along with their granular enrichments is studied in detail.

  3. Coastal Modeling System Advanced Topics

    Science.gov (United States)

    2012-06-18

    22 June 2012 - Day 5  Debugging and Problem solving  Model Calibration  Post-processing Coastal and Hydraulics Laboratory Focus of...Efficiently: • The setup process is fast and without wasted time or effort 3 Coastal and Hydraulics Laboratory 4 Coastal Modeling System (CMS) What...is the CMS? Integrated wave, current, and morphology change model in the Surface- water Modeling System (SMS). Why CMS? Operational at 10

  4. Safeguards system effectiveness modeling

    International Nuclear Information System (INIS)

    Bennett, H.A.; Boozer, D.D.; Chapman, L.D.; Daniel, S.L.; Engi, D.; Hulme, B.L.; Varnado, G.B.

    1976-01-01

    A general methodology for the comparative evaluation of physical protection system effectiveness at nuclear facilities is presently under development. The approach is applicable to problems of sabotage or theft at fuel cycle facilities. The overall methodology and the primary analytic techniques used to assess system effectiveness are briefly outlined

  5. Safeguards system effectiveness modeling

    International Nuclear Information System (INIS)

    Bennett, H.A.; Boozer, D.D.; Chapman, L.D.; Daniel, S.L.; Engi, D.; Hulme, B.L.; Varnado, G.B.

    1976-01-01

    A general methodology for the comparative evaluation of physical protection system effectiveness at nuclear facilities is presently under development. The approach is applicable to problems of sabotage or theft at fuel cycle facilities. In this paper, the overall methodology and the primary analytic techniques used to assess system effectiveness are briefly outlined

  6. Understanding the causes and implications of endothelial metabolic variation in cardiovascular disease through genome scale metabolic modeling

    Directory of Open Access Journals (Sweden)

    Sarah eMcGarrity

    2016-04-01

    Full Text Available High-throughput biochemical profiling has led to a requirement for advanced data interpretation techniques capable of integrating the analysis of gene, protein, and metabolic profiles to shed light on genotype-phenotype relationships. Herein, we consider the current state of knowledge of endothelial cell (EC metabolism and its connections to cardiovascular disease, and explore the use of genome scale metabolic models (GEMs for integrating metabolic and genomic data. GEMs combine gene expression and metabolic data acting as frameworks for their analysis and, ultimately, afford mechanistic understanding of how genetic variation impacts metabolism. We demonstrate how GEMs can be used to investigate cardiovascular disease-related genetic variation, drug resistance mechanisms, and novel metabolic pathways, in ECs. The application of GEMs in personalized medicine is also highlighted. Particularly, we focus on the potential of GEMs to identify metabolic biomarkers of endothelial dysfunction and to discover methods of stratifying treatments for cardiovascular diseases based on individual genetic markers. Recent advances in systems biology methodology, and how these methodologies can be applied to understand EC metabolism in both health and disease, are thus highlighted.

  7. Study on Physical Properties and Chemical Composition of Some Myanmar Gems

    International Nuclear Information System (INIS)

    Kyaw Myint Htoo; Tun Khin; Sein Htoon

    2004-05-01

    Physical properties of some Myanmar gems were studied by using refractometer, dichroscope, polariscope, SG test, UV test and microscope. Then, chemical composition were investigated by XRF-technique. After that, gem identification, evaluation, colour improvement were studied according to these physical properties and chemical composition

  8. Characterization of GEM foils and materials simulation, measurements and interferometric monitoring tools

    CERN Document Server

    Benussi, Luigi

    2015-01-01

    The GE1/1 CMS project consists of 144 GEM chambers of about 0.5 qm active area each, based on the triple GEMs technology, to be installed in the very forward region of the CMS endcap during the long shutdown of LHC in 2108-2019. GE1/1 chambers will be operated for decades in harsh environment, and are expected to perform consistently providing good space and time resolution and excellent rate capabilities. An extensive material science simulation and measurement campaign is in progress to characterize GEM materials, with main focus on the GEM foils. Results are presented on full Finite Element Analysis simulations, measurement of tensile properties and humidity absorption coefficients, both for unused and irradiated samples. Preliminary results are shown on interferometric methods based on Moirè fringes for the monitoring of GEM foils mechanical properties during chamber construction.

  9. Investigations on Important Properties of the 10 cm x 10 cm GEM Prototype

    CERN Document Server

    Saenboonruang, Kiadtisak; Kulasri, Kittipong; Ritthirong, Anawat

    2015-01-01

    The Gas Electron Multiplier (GEM) detector is one of promising particle and radiation detectors that has been improved greatly from previous gas detectors. The improvement includes better spatial resolutions, higher detection rate capabilities, and flexibilities in designs. In particular, the 10 cm x 10 cm GEM prototype is designed and provided by the Gas Detectors Development group (GDD) at CERN, Switzerland. With its simplicity in operations and designs, while still maintaining high qualities, the GEM prototype is suitable for both start-up and advanced researches. This article aims to report the investigations on some important properties of the 10 cm x 10 cm GEM detector using current measurement and signal counting. Results have shown that gains of the GEM prototype exponentially increase as voltage supplied to the detector increases, while the detector reaches full efficiency (plateau region) when the voltage is greater than 4100 V. In terms of signal sharing between X and Y strips of the readout, X str...

  10. Gain uniformity experimental study performed on triple-GEM gas detector

    International Nuclear Information System (INIS)

    Dong Liyuan; Qi Huirong; Lu Xinyu; Ouyang Qun; Chen Yuanbo; Li Yuhong

    2012-01-01

    With the application of the two-dimensional GEM gaseous detector in X-ray imaging, the correction method of gain uniformity caused by triple-GEM avalanche structures and electric field uniformity should be studied. The paper reported the study of the triple-GEM detector with effective area 100 mm × 100 mm used the Pad's size of 9.5 mm × 9.5 mm. In the test, 100 readout channels were designed. Results showed that gain remained stable over time; at air flow increases, gain from increases obviously to changes very little. Particularly, triple-GEM's gain uniformity was very good (more than 80%) and the range of energy resolution was from 0.18 to 0.2. To improve gain consistency of results, the difference value revised was obtained to be about 0.1 by the least square method. It provided a better method to improve gain uniformity of GEM detector. (authors)

  11. Gas electron multiplier (GEM) operation with tissue-equivalent gases at various pressures

    International Nuclear Information System (INIS)

    Farahmand, M.; Bos, A.J.J.; Eijk, C.W.E. van

    2003-01-01

    We have studied the operation of two different Gas Electron Multiplier (GEM) structures in both methane and propane based Tissue-Equivalent (TE) gases at different pressures varying from 0.1 to 1 atm. This work was motivated to explore the possibility of using a GEM for a new type of Tissue Equivalent Proportional Counter. In methane based TE gas, a maximum safe GEM gain of 1.5x10 3 has been reached while in propane based TE gas this is 6x10 3 . These maxima have been reached at different gas pressures depending on GEM structure and TE gas. Furthermore, we observed a decrease of the GEM gain in time before it becomes stable. Charge up/polarisation effects can explain this

  12. Triple-GEM detectors for the innermost region of the muon apparatus at the LHCb experiment

    CERN Document Server

    Poli-Lener, M; Bencivenni, G

    2005-01-01

    The LHCb experiment will take place at the future LHC accelerator at CERN and will start in 2007. It is a single arm spectrometer to precision measurements of CP violation and rare decays in the b quark sector. Recent experimental results have shown that CP violation is large in this sector. LHCb is designed with a robust and flexible trigger in order to extensively gain access to a wide spread of different physical processes involving the beauty particles. This will allow to over-constrain the Standard Model predictions about $\\mathcal{CP}$ violation, and to discover any possible inconsistency, which would reveal the presence of ''New Physics''. The work presented in this thesis has two main parts: the development of a charged particle detector based on Gas Electron Multiplication (GEM) and the study of luminosity measurements with the physical channels $Z^{0} \\rightarrow \\mu^{+} \\mu^{-}$ and $W^{\\pm} \\rightarrow \\mu^{\\pm} \

  13. Gaseous elemental mercury (GEM) fluxes over canopy of two typical subtropical forests in south China

    Science.gov (United States)

    Yu, Qian; Luo, Yao; Wang, Shuxiao; Wang, Zhiqi; Hao, Jiming; Duan, Lei

    2018-01-01

    Mercury (Hg) exchange between forests and the atmosphere plays an important role in global Hg cycling. The present estimate of global emission of Hg from natural source has large uncertainty, partly due to the lack of chronical and valid field data, particularly for terrestrial surfaces in China, the most important contributor to global atmospheric Hg. In this study, the micrometeorological method (MM) was used to continuously observe gaseous elemental mercury (GEM) fluxes over forest canopy at a mildly polluted site (Qianyanzhou, QYZ) and a moderately polluted site (Huitong, HT, near a large Hg mine) in subtropical south China for a full year from January to December in 2014. The GEM flux measurements over forest canopy in QYZ and HT showed net emission with annual average values of 6.67 and 0.30 ng m-2 h-1, respectively. Daily variations of GEM fluxes showed an increasing emission with the increasing air temperature and solar radiation in the daytime to a peak at 13:00, and decreasing emission thereafter, even as a GEM sink or balance at night. High temperature and low air Hg concentration resulted in the high Hg emission in summer. Low temperature in winter and Hg absorption by plant in spring resulted in low Hg emission, or even adsorption in the two seasons. GEM fluxes were positively correlated with air temperature, soil temperature, wind speed, and solar radiation, while it is negatively correlated with air humidity and atmospheric GEM concentration. The lower emission fluxes of GEM at the moderately polluted site (HT) when compared with that in the mildly polluted site (QYZ) may result from a much higher adsorption fluxes at night in spite of a similar or higher emission fluxes during daytime. This shows that the higher atmospheric GEM concentration at HT restricted the forest GEM emission. Great attention should be paid to forests as a crucial increasing Hg emission source with the decreasing atmospheric GEM concentration in polluted areas because of Hg

  14. The stable K0 giant star β Gem

    Energy Technology Data Exchange (ETDEWEB)

    Gray, David F., E-mail: dfgray@uwo.ca [Department of Physics and Astronomy, University of Western Ontario, 1151 Richmond Street, London, Ontario, N6A 3K7 (Canada)

    2014-12-01

    A nine-season spectroscopic study of the photosphere of β Gem (K0 III) shows this low-luminosity giant to be stable, with no effective temperature variations above ∼2 K, and no secular temperature variations over the 2002-2010 time span above 0.2 K per year. The radial-velocity variations are consistent with an orbital variation of ∼40 m s{sup –1}. The projected rotation rate is found to be 1.70 ± 0.20 km s{sup –1} with a macroturbulence dispersion of 4.53 ± 0.10 km s{sup –1}. The third-signature plot is also invariant and shows a granulation velocity gradient 20% smaller than the solar gradient. The absolute shift of the third-signature plot gives a blueshift-corrected radial velocity of 3385 ± 70 m s{sup –1}. Bisector mapping of the Fe I λ6253 line yields a flux deficit of 12% ± 1% in area, somewhat smaller than for other giants, but the shape and the position of the peak at 4.8 km s{sup –1} is consistent with other giants. All of the investigated photospheric parameters are consistent with β Gem being a low-luminosity giant in agreement with its absolute magnitude.

  15. Gain characteristics of a 100 μm thick GEM in Krypton-CO2 mixtures

    Science.gov (United States)

    Roque, R. C.; Natal da Luz, H.; Carramate, L. F. N. D.; Azevedo, C. D. R.; Mir, J. A.; Amaro, F. D.

    2017-12-01

    The operation of a Micropattern Gaseous Detector (MPGD) comprising a cascade of two non-standard Gas Electron Multipliers (GEM) made from a 100 μm kapton foil was evaluated in pure krypton and in krypton-CO2 mixtures. The final avalanche charge was collected in a 2D strip readout, providing an active area of 10×10 cm2 for the entire detection system. For each mixture, the effective gain and energy resolution were measured as a function of the electric field in the drift, transfer and induction regions. Using X-rays from a 55Fe radioactive source (5.9 keV), gains close to 104 and energy resolution of 22% (FWHM) were achieved in pure krypton under stable conditions, showing the potential of the experimental setup for the following imaging studies.

  16. Mechanical Systems, Classical Models

    CERN Document Server

    Teodorescu, Petre P

    2007-01-01

    All phenomena in nature are characterized by motion; this is an essential property of matter, having infinitely many aspects. Motion can be mechanical, physical, chemical or biological, leading to various sciences of nature, mechanics being one of them. Mechanics deals with the objective laws of mechanical motion of bodies, the simplest form of motion. In the study of a science of nature mathematics plays an important role. Mechanics is the first science of nature which was expressed in terms of mathematics by considering various mathematical models, associated to phenomena of the surrounding nature. Thus, its development was influenced by the use of a strong mathematical tool; on the other hand, we must observe that mechanics also influenced the introduction and the development of many mathematical notions. In this respect, the guideline of the present book is precisely the mathematical model of mechanics. A special accent is put on the solving methodology as well as on the mathematical tools used; vectors, ...

  17. Stochastic Modelling of Energy Systems

    DEFF Research Database (Denmark)

    Andersen, Klaus Kaae

    2001-01-01

    In this thesis dynamic models of typical components in Danish heating systems are considered. Emphasis is made on describing and evaluating mathematical methods for identification of such models, and on presentation of component models for practical applications. The thesis consists of seven...... of component models, such as e.g. heat exchanger and valve models, adequate for system simulations. Furthermore, the thesis demonstrates and discusses the advantages and disadvantages of using statistical methods in conjunction with physical knowledge in establishing adequate component models of heating...... research papers (case studies) together with a summary report. Each case study takes it's starting point in typical heating system components and both, the applied mathematical modelling methods and the application aspects, are considered. The summary report gives an introduction to the scope...

  18. Generation of an atlas for commodity chemical production in Escherichia coli and a novel pathway prediction algorithm, GEM-Path.

    Science.gov (United States)

    Campodonico, Miguel A; Andrews, Barbara A; Asenjo, Juan A; Palsson, Bernhard O; Feist, Adam M

    2014-09-01

    The production of 75% of the current drug molecules and 35% of all chemicals could be achieved through bioprocessing (Arundel and Sawaya, 2009). To accelerate the transition from a petroleum-based chemical industry to a sustainable bio-based industry, systems metabolic engineering has emerged to computationally design metabolic pathways for chemical production. Although algorithms able to provide specific metabolic interventions and heterologous production pathways are available, a systematic analysis for all possible production routes to commodity chemicals in Escherichia coli is lacking. Furthermore, a pathway prediction algorithm that combines direct integration of genome-scale models at each step of the search to reduce the search space does not exist. Previous work (Feist et al., 2010) performed a model-driven evaluation of the growth-coupled production potential for E. coli to produce multiple native compounds from different feedstocks. In this study, we extended this analysis for non-native compounds by using an integrated approach through heterologous pathway integration and growth-coupled metabolite production design. In addition to integration with genome-scale model integration, the GEM-Path algorithm developed in this work also contains a novel approach to address reaction promiscuity. In total, 245 unique synthetic pathways for 20 large volume compounds were predicted. Host metabolism with these synthetic pathways was then analyzed for feasible growth-coupled production and designs could be identified for 1271 of the 6615 conditions evaluated. This study characterizes the potential for E. coli to produce commodity chemicals, and outlines a generic strain design workflow to design production strains. Copyright © 2014 International Metabolic Engineering Society. Published by Elsevier Inc. All rights reserved.

  19. Model Reduction of Hybrid Systems

    DEFF Research Database (Denmark)

    Shaker, Hamid Reza

    for model reduction of switched systems is based on the switching generalized gramians. The reduced order switched system is guaranteed to be stable for all switching signal in this method. This framework uses stability conditions which are based on switching quadratic Lyapunov functions which are less...... conservative than the stability conditions based on common quadratic Lyapunov functions. The stability conditions which are used for this method are very useful in model reduction and design problems because they have slack variables in the conditions. Similar conditions for a class of switched nonlinear......High-Technological solutions of today are characterized by complex dynamical models. A lot of these models have inherent hybrid/switching structure. Hybrid/switched systems are powerful models for distributed embedded systems design where discrete controls are applied to continuous processes...

  20. Distribution system modeling and analysis

    CERN Document Server

    Kersting, William H

    2001-01-01

    For decades, distribution engineers did not have the sophisticated tools developed for analyzing transmission systems-often they had only their instincts. Things have changed, and we now have computer programs that allow engineers to simulate, analyze, and optimize distribution systems. Powerful as these programs are, however, without a real understanding of the operating characteristics of a distribution system, engineers using the programs can easily make serious errors in their designs and operating procedures. Distribution System Modeling and Analysis helps prevent those errors. It gives readers a basic understanding of the modeling and operating characteristics of the major components of a distribution system. One by one, the author develops and analyzes each component as a stand-alone element, then puts them all together to analyze a distribution system comprising the various shunt and series devices for power-flow and short-circuit studies. He includes the derivation of all models and includes many num...

  1. Gadget for epilithic microalgal sampling (GEMS Dispositivo para amostragem de microalgas epilíticas

    Directory of Open Access Journals (Sweden)

    LGC. Canani

    2010-05-01

    Full Text Available Benthic microalgae sampling in lotic systems is carried out using either artificial or natural substrate. Natural substrate is more suitable for biomass and productivity estimates as well as biodiversity assessment because it contains the communities that are typical of the environment. We present a new gadget for epilithic microalgae sampling (GEMS that allows sampling in situ when it is impossible to remove the substrate from the river bed. The sampler consists of an acrylic box with a 25 cm diameter opening on its base that allows access to the substrate. This gadget can be used in shallow plan bedrock streams and it keeps the sample area isolated as much as possible minimising losses and contamination. It is also easy to construct and handle.As amostragens de microalgas bênticas em sistemas lóticos são realizadas através do uso de substrato natural ou artificial. Substratos naturais são mais adequados para a estimativa de biomassa e produtividade, assim como, para a avaliação de biodiversidade, porque eles contêm as comunidades que são típicas de um determinado ambiente. Nós apresentamos um novo dispositivo para amostragem de microalgas epilíticas (GEMS que permite a amostragem in situ, quando é impossível remover o substrato do leito do rio. O amostrador consiste em uma caixa de acrílico com uma abertura de 25 cm de diâmetro em sua base que permite acesso ao substrato. O amostrador pode ser usado em riachos rasos e de leito rochoso e plano, e mantém a área amostral o mais isolada possível, minimizando perdas e contaminação, além de ser fácil de construir e manusear.

  2. Hydronic distribution system computer model

    Energy Technology Data Exchange (ETDEWEB)

    Andrews, J.W.; Strasser, J.J.

    1994-10-01

    A computer model of a hot-water boiler and its associated hydronic thermal distribution loop has been developed at Brookhaven National Laboratory (BNL). It is intended to be incorporated as a submodel in a comprehensive model of residential-scale thermal distribution systems developed at Lawrence Berkeley. This will give the combined model the capability of modeling forced-air and hydronic distribution systems in the same house using the same supporting software. This report describes the development of the BNL hydronics model, initial results and internal consistency checks, and its intended relationship to the LBL model. A method of interacting with the LBL model that does not require physical integration of the two codes is described. This will provide capability now, with reduced up-front cost, as long as the number of runs required is not large.

  3. Radiation imaging with optically read out GEM-based detectors

    Science.gov (United States)

    Brunbauer, F. M.; Lupberger, M.; Oliveri, E.; Resnati, F.; Ropelewski, L.; Streli, C.; Thuiner, P.; van Stenis, M.

    2018-02-01

    Modern imaging sensors allow for high granularity optical readout of radiation detectors such as MicroPattern Gaseous Detectors (MPGDs). Taking advantage of the high signal amplification factors achievable by MPGD technologies such as Gaseous Electron Multipliers (GEMs), highly sensitive detectors can be realised and employing gas mixtures with strong scintillation yield in the visible wavelength regime, optical readout of such detectors can provide high-resolution event representations. Applications from X-ray imaging to fluoroscopy and tomography profit from the good spatial resolution of optical readout and the possibility to obtain images without the need for extensive reconstruction. Sensitivity to low-energy X-rays and energy resolution permit energy resolved imaging and material distinction in X-ray fluorescence measurements. Additionally, the low material budget of gaseous detectors and the possibility to couple scintillation light to imaging sensors via fibres or mirrors makes optically read out GEMs an ideal candidate for beam monitoring detectors in high energy physics as well as radiotherapy. We present applications and achievements of optically read out GEM-based detectors including high spatial resolution imaging and X-ray fluorescence measurements as an alternative readout approach for MPGDs. A detector concept for low intensity applications such as X-ray crystallography, which maximises detection efficiency with a thick conversion region but mitigates parallax-induced broadening is presented and beam monitoring capabilities of optical readout are explored. Augmenting high resolution 2D projections of particle tracks obtained with optical readout with timing information from fast photon detectors or transparent anodes for charge readout, 3D reconstruction of particle trajectories can be performed and permits the realisation of optically read out time projection chambers. Combining readily available high performance imaging sensors with compatible

  4. Bedeutung des Gemüsebaus für die Landwirtschaft von Wielkopolska

    Directory of Open Access Journals (Sweden)

    Karolina Jąder

    2009-01-01

    Full Text Available In dem Artikel wurde die Bedeutung des Gemüsebaus für die Landwirtschaft der Region Wielkopolska präsentiert. Diese Bedeutung wurde mit Hilfe von einigen Kriterien bestimmt. Es wurden dargestellt: der Anteil der Gemüsefläche an der gesamten landwirtschaftlichen Nutzfläche von Wielkopolska und der Gemüseanteil in der Brutto- und Warenproduktion der regionalen Landwirtschaft und der Pflanzenabteilung. Der Anteil der Freilandgemüsefläche an der landwirtschaftlichen Nutzfläche lag bei 1,36 bis 1,56 Prozent und der Anteil der Gewächshausgemüsefläche an der landwirtschaftlichen Nutzfläche oszillierte von 0,017 bis 0,050 Prozent. Die Gemüseproduktion lag bei 4,67 Prozent der Bruttoproduktion der Landwirtschaft von Wielkopolska, und der Anteil der Gemüseproduktion an der Warenproduktion der Landwirtschaft war in der Zeit auf einem ähnlichen Niveau – 4,66 Prozent. In der Pflanzenabteilung war die Bedeutung des Gemüsebaus noch größer als in der ganzen Landwirtschaft. Der Anteil von Gemüse an der Warenproduktion der Pflanzenabteilung lag durchschnittlich in den untersuchten Jahren bei 28, 54 Prozent.

  5. Simulation of the dielectric charging-up effect in a GEM detector

    International Nuclear Information System (INIS)

    Alfonsi, M.; Croci, G.; Duarte Pinto, S.; Rocco, E.; Ropelewski, L.; Sauli, F.; Veenhof, R.; Villa, M.

    2012-01-01

    The charging up effect is well-known in detectors containing dielectric materials and it is due to electrons and ions liberated in an avalanche and collected on the dielectric surfaces. In particular in Gas Electron Multiplier (GEM) based detectors, charges can be captured by the Kapton that separates top and bottom electrodes. The collection of a substantial number of charges on the dielectric surfaces induces a modification of the field inside the GEM holes that implies important consequences on some fundamental parameters such as the electron transparency and the effective gain. The correct simulation of this effect opens new ways to the detailed study of the processes that happens in a GEM-based detector and gives the possibility to optimise the GEM geometry in order to avoid it. This paper compares results of the measurements and the simulations, with and without the introduction of the charging-up effect, of the GEM electron transparency in the case of a single GEM detector. The introduction of the charging up effect in the simulation resulted to be crucial in order to get the proper agreement with the measurements. The measurements and simulations of the GEM effective gain will be the subject of a future work.

  6. Towards an automatic wind speed and direction profiler for Wide Field adaptive optics systems

    Science.gov (United States)

    Sivo, G.; Turchi, A.; Masciadri, E.; Guesalaga, A.; Neichel, B.

    2018-05-01

    Wide Field Adaptive Optics (WFAO) systems are among the most sophisticated adaptive optics (AO) systems available today on large telescopes. Knowledge of the vertical spatio-temporal distribution of wind speed (WS) and direction (WD) is fundamental to optimize the performance of such systems. Previous studies already proved that the Gemini Multi-Conjugated AO system (GeMS) is able to retrieve measurements of the WS and WD stratification using the SLOpe Detection And Ranging (SLODAR) technique and to store measurements in the telemetry data. In order to assess the reliability of these estimates and of the SLODAR technique applied to such complex AO systems, in this study we compared WS and WD values retrieved from GeMS with those obtained with the atmospheric model Meso-NH on a rich statistical sample of nights. It has previously been proved that the latter technique provided excellent agreement with a large sample of radiosoundings, both in statistical terms and on individual flights. It can be considered, therefore, as an independent reference. The excellent agreement between GeMS measurements and the model that we find in this study proves the robustness of the SLODAR approach. To bypass the complex procedures necessary to achieve automatic measurements of the wind with GeMS, we propose a simple automatic method to monitor nightly WS and WD using Meso-NH model estimates. Such a method can be applied to whatever present or new-generation facilities are supported by WFAO systems. The interest of this study is, therefore, well beyond the optimization of GeMS performance.

  7. Code and Solution Verification of 3D Numerical Modeling of Flow in the Gust Erosion Chamber

    Science.gov (United States)

    Yuen, A.; Bombardelli, F. A.

    2014-12-01

    Erosion microcosms are devices commonly used to investigate the erosion and transport characteristics of sediments at the bed of rivers, lakes, or estuaries. In order to understand the results these devices provide, the bed shear stress and flow field need to be accurately described. In this research, the UMCES Gust Erosion Microcosm System (U-GEMS) is numerically modeled using Finite Volume Method. The primary aims are to simulate the bed shear stress distribution at the surface of the sediment core/bottom of the microcosm, and to validate the U-GEMS produces uniform bed shear stress at the bottom of the microcosm. The mathematical model equations are solved by on a Cartesian non-uniform grid. Multiple numerical runs were developed with different input conditions and configurations. Prior to developing the U-GEMS model, the General Moving Objects (GMO) model and different momentum algorithms in the code were verified. Code verification of these solvers was done via simulating the flow inside the top wall driven square cavity on different mesh sizes to obtain order of convergence. The GMO model was used to simulate the top wall in the top wall driven square cavity as well as the rotating disk in the U-GEMS. Components simulated with the GMO model were rigid bodies that could have any type of motion. In addition cross-verification was conducted as results were compared with numerical results by Ghia et al. (1982), and good agreement was found. Next, CFD results were validated by simulating the flow within the conventional microcosm system without suction and injection. Good agreement was found when the experimental results by Khalili et al. (2008) were compared. After the ability of the CFD solver was proved through the above code verification steps. The model was utilized to simulate the U-GEMS. The solution was verified via classic mesh convergence study on four consecutive mesh sizes, in addition to that Grid Convergence Index (GCI) was calculated and based on

  8. Intrusion detection: systems and models

    Science.gov (United States)

    Sherif, J. S.; Dearmond, T. G.

    2002-01-01

    This paper puts forward a review of state of the art and state of the applicability of intrusion detection systems, and models. The paper also presents a classfication of literature pertaining to intrusion detection.

  9. Plant and safety system model

    International Nuclear Information System (INIS)

    Beltracchi, Leo

    1999-01-01

    The design and development of a digital computer-based safety system for a nuclear power plant is a complex process. The process of design and product development must result in a final product free of critical errors; operational safety of nuclear power plants must not be compromised. This paper focuses on the development of a safety system model to assist designers, developers, and regulators in establishing and evaluating requirements for a digital computer-based safety system. The model addresses hardware, software, and human elements for use in the requirements definition process. The purpose of the safety system model is to assist and serve as a guide to humans in the cognitive reasoning process of establishing requirements. The goals in the use of the model are to: (1) enhance the completeness of the requirements and (2) reduce the number of errors associated with the requirements definition phase of a project

  10. Lingua(gem sob duas perspectivas teóricas

    Directory of Open Access Journals (Sweden)

    Lidiomar José Mascarello

    2010-02-01

    Destacaremos nesse breve percurso teórico dois olhares possíveis para esse fenômeno, a língua(gem, que é tão natural e ao mesmo tempo tão complexo de ser explicado e entendido. De um lado, questões psíquicas individuais, como um processo evolutivo que opera em escala de tempo e que depende da maturação dos processos neurais e de toda rede neuronial e da capacidade inata do sujeito, ou seja, uma visão com tendências mais cognitivista, e por outro, da exposição à interação sócio-ambiental, de cunho interacionista, pois, acreditamos que são complementares e não restritivas ou excludentes.

  11. A triple-GEM detector for high-rate particle triggering

    Energy Technology Data Exchange (ETDEWEB)

    Alfonsi, M.; Bencivenni, G.; Simone, P. de; Murtas, F.; Poli Lener, M.; Bonivento, W. E-mail: walter.bonivento@cern.ch; Cardini, A.; Deplano, C.; Pinci, D.; Raspino, D.; Saitta, B

    2004-06-01

    We show that adding CF{sub 4} to the standard Ar/CO{sub 2} gas mixture allows to substantially improve the time resolution of triple-GEM detectors. In this paper we discuss measurements of time resolution, discharge probability per incident charged particle and pad multiplicity of a triple-GEM detector with pad readout, with new gas mixtures with CF{sub 4} and isobutane. Results for detectors with GEM foil size of both 10x10 cm{sup 2} and 20x24 cm{sup 2} are presented.

  12. The development of neutron detectors for the GEM instrument at ISIS

    Energy Technology Data Exchange (ETDEWEB)

    Rhodes, N.J.; Johnson, M.W.; Schooneveld, E.M. [ISIS Facility, Rutherford Appleton Laboratory, Chilton, Didcot, Oxon (United Kingdom)

    2001-03-01

    GEM is a new General Materials diffractometer now being commissioned at ISIS. To meet its broad based scientific programme GEM requires a large area position sensitive detector which covers a wide range of scattering angles and exhibits a high neutron count rate stability. This paper discusses the design of a ZnS/{sup 6}Li fibre coupled detector array that meets the GEM requirements. Typical detector characteristics are documented together with the current status of the project. Two thirds of the detector array are operational and from the results obtained to date it is already obvious that the impact of this instrument on neutron scattering studies will be profound. (author)

  13. GEM-based gaseous photomultipliers for UV and visible photon imaging

    International Nuclear Information System (INIS)

    Moermann, D.; Balcerzyk, M.; Breskin, A.; Chechik, R.; Singh, B.K.; Buzulutskov, A.

    2003-01-01

    We present the current status of our research on GEM-based gaseous photomultipliers. Detectors combining multi-GEM electron multipliers with semi-transparent and reflective photocathodes are discussed. We present recent progress in extending the sensitivity of these detectors into the visible range. We demonstrate the long-term stability of an argon-sealed bi-alkali photo-diode and provide preliminary results of a gas-sealed Kapton-GEM detector with a bi-alkali photocathode. The problem of ion-induced secondary electron emission is addressed

  14. Mathematical modeling of aeroelastic systems

    Science.gov (United States)

    Velmisov, Petr A.; Ankilov, Andrey V.; Semenova, Elizaveta P.

    2017-12-01

    In the paper, the stability of elastic elements of a class of designs that are in interaction with a gas or liquid flow is investigated. The definition of the stability of an elastic body corresponds to the concept of stability of dynamical systems by Lyapunov. As examples the mathematical models of flowing channels (models of vibration devices) at a subsonic flow and the mathematical models of protective surface at a supersonic flow are considered. Models are described by the related systems of the partial differential equations. An analytic investigation of stability is carried out on the basis of the construction of Lyapunov-type functionals, a numerical investigation is carried out on the basis of the Galerkin method. The various models of the gas-liquid environment (compressed, incompressible) and the various models of a deformable body (elastic linear and elastic nonlinear) are considered.

  15. ABSTRACT MODELS FOR SYSTEM VIRTUALIZATION

    Directory of Open Access Journals (Sweden)

    M. G. Koveshnikov

    2015-05-01

    Full Text Available The paper is dedicated to issues of system objects securing (system files and user system or application configuration files against unauthorized access including denial of service attacks. We have suggested the method and developed abstract system virtualization models, which are used toresearch attack scenarios for different virtualization modes. Estimation for system tools virtualization technology effectiveness is given. Suggested technology is based on redirection of access requests to system objects shared among access subjects. Whole and partial system virtualization modes have been modeled. The difference between them is the following: in the whole virtualization mode all copies of access system objects are created whereon subjects’ requests are redirected including corresponding application objects;in the partial virtualization mode corresponding copies are created only for part of a system, for example, only system objects for applications. Alternative solutions effectiveness is valued relating to different attack scenarios. We consider proprietary and approved technical solution which implements system virtualization method for Microsoft Windows OS family. Administrative simplicity and capabilities of correspondingly designed system objects security tools are illustrated on this example. Practical significance of the suggested security method has been confirmed.

  16. Aerodynamic and Mechanical System Modelling

    DEFF Research Database (Denmark)

    Jørgensen, Martin Felix

    This thesis deals with mechanical multibody-systems applied to the drivetrain of a 500 kW wind turbine. Particular focus has been on gearbox modelling of wind turbines. The main part of the present project involved programming multibody systems to investigate the connection between forces, moments...

  17. Preface: the hydra model system.

    Science.gov (United States)

    Galliot, Brigitte

    2012-01-01

    The freshwater Hydra polyp emerged as a model system in 1741 when Abraham Trembley not only discovered its amazing regenerative potential, but also demonstrated that experimental manipulations pave the way to research in biology. Since then, Hydra flourished as a potent and fruitful model system to help answer questions linked to cell and developmental biology, as such as the setting up of an organizer to regenerate a complex missing structure, the establishment and maintainance of polarity in a multicellular organism, the development of mathematical models to explain the robust developmental rules observed in this animal, the maintainance of stemness and multipotency in a highly dynamic environment, the plasticity of differentiated cells, to name but a few. However the Hydra model system is not restricted to cell and developmental biology; during the past 270 years it has also been heavily used to investigate the relationships between Hydra and its environment, opening new horizons concerning neurophysiology, innate immunity, ecosystems, ecotoxicology, symbiosis...

  18. Modeling Multi-Level Systems

    CERN Document Server

    Iordache, Octavian

    2011-01-01

    This book is devoted to modeling of multi-level complex systems, a challenging domain for engineers, researchers and entrepreneurs, confronted with the transition from learning and adaptability to evolvability and autonomy for technologies, devices and problem solving methods. Chapter 1 introduces the multi-scale and multi-level systems and highlights their presence in different domains of science and technology. Methodologies as, random systems, non-Archimedean analysis, category theory and specific techniques as model categorification and integrative closure, are presented in chapter 2. Chapters 3 and 4 describe polystochastic models, PSM, and their developments. Categorical formulation of integrative closure offers the general PSM framework which serves as a flexible guideline for a large variety of multi-level modeling problems. Focusing on chemical engineering, pharmaceutical and environmental case studies, the chapters 5 to 8 analyze mixing, turbulent dispersion and entropy production for multi-scale sy...

  19. HISTORY OF GALAXY INTERACTIONS AND THEIR IMPACT ON STAR FORMATION OVER THE LAST 7 Gyr FROM GEMS

    International Nuclear Information System (INIS)

    Jogee, Shardha; Miller, Sarah H.; Penner, Kyle; Skelton, Rosalind E.; Somerville, Rachel S.; Bell, Eric F.; Rix, Hans-Walter; Robaina, Aday R.; Borch, Andrea; Haeussler, Boris; Jahnke, Knud; Conselice, Christopher J.; Zheng, Xian Zhong; Barazza, Fabio D.; Barden, Marco; Beckwith, Steven V. W.; Caldwell, John A. R.; Peng, Chien Y.; Heymans, Catherine; McIntosh, Daniel H.

    2009-01-01

    We perform a comprehensive estimate of the frequency of galaxy mergers and their impact on star formation over z∼ 0.24-0.80 (lookback time T b ∼ 3-7 Gyr) using ∼3600 (M≥ 1 x 10 9 M sun ) galaxies with GEMS Hubble Space Telescope, COMBO-17, and Spitzer data. Our results are as follows. (1) Among ∼790 high-mass (M≥ 2.5 x 10 10 M sun ) galaxies, the visually based merger fraction over z∼ 0.24-0.80, ranges from 9% ± 5% to 8% ± 2%. Lower limits on the major merger and minor merger fraction over this interval range from 1.1% to 3.5%, and 3.6% to 7.5%, respectively. This is the first, albeit approximate, empirical estimate of the frequency of minor mergers over the last 7 Gyr. Assuming a visibility timescale of ∼0.5 Gyr, it follows that over T b ∼ 3-7 Gyr, ∼68% of high-mass systems have undergone a merger of mass ratio >1/10, with ∼16%, 45%, and 7% of these corresponding respectively to major, minor, and ambiguous 'major or minor' mergers. The average merger rate is ∼ a few x10 -4 galaxies Gyr -1 Mpc -3 . Among ∼2840 blue-cloud galaxies of mass M≥ 1.0 x 10 9 M sun , similar results hold. (2) We compare the empirical merger fraction and merger rate for high-mass galaxies to three Λ cold dark matter-based models: halo occupation distribution models, semi-analytic models, and hydrodynamic SPH simulations. We find qualitative agreement between observations and models such that the (major+minor) merger fraction or rate from different models bracket the observations, and show a factor of 5 dispersion. Near-future improvements can now start to rule out certain merger scenarios. (3) Among ∼3698 M≥ 1.0 x 10 9 M sun galaxies, we find that the mean star formation rate (SFR) of visibly merging systems is only modestly enhanced compared to non-interacting galaxies over z∼ 0.24-0.80. Visibly merging systems only account for a small fraction ( b ∼ 3-7 Gyr. This complements the results of Wolf et al. over a shorter time interval of T b ∼ 6

  20. System Convergence in Transport Modelling

    DEFF Research Database (Denmark)

    Rich, Jeppe; Nielsen, Otto Anker; Cantarella, Guilio E.

    2010-01-01

    A fundamental premise of most applied transport models is the existence and uniqueness of an equilibrium solution that balances demand x(t) and supply t(x). The demand consists of the people that travel in the transport system and on the defined network, whereas the supply consists of the resulting...... level-of-service attributes (e.g., travel time and cost) offered to travellers. An important source of complexity is the congestion, which causes increasing demand to affect travel time in a non-linear way. Transport models most often involve separate models for traffic assignment and demand modelling...

  1. Interpreting the Global Enteric Multicenter Study (GEMS Findings on Sanitation, Hygiene, and Diarrhea.

    Directory of Open Access Journals (Sweden)

    Jonny Crocker

    2016-05-01

    Full Text Available In this Perspective on the GEMS study by Kelly Baker and colleagues, Jonny Crocker and Jamie Bartram consider the implications of associations found and not found between diarrheal disease and sanitation and hygiene.

  2. Measurement of spark probability of GEM detector for CBM muon chamber (MUCH)

    CERN Document Server

    Biswas, S.; Frankenfeld, U.; Garabatos, C.; Hehner, J.; Kleipa, V.; Morhardt, T.; Schmidt, C.J.; Schmidt, H.R.; Wiechula, J.

    2015-11-11

    The stability of triple GEM detector setups in an environment of high energetic showers is studied. To this end the spark probability in a shower environment is compared to the spark probability in a pion beam.

  3. Gem-diol and Ketone Crystal-to-crystal Transition Phenomena.

    Science.gov (United States)

    Bo, Zhang; Sitong, Chen; Weiming, Guo; Weijing, Zhang; Lin, Wang; Li, Yang; Jianguo, Zhang

    2017-10-18

    The generally thought unstable diol compound tetrazyl gem-diol (1, H 2 DTMdiol·2H 2 O), was firstly obtained in crystalline form by culturing the filtrate for ten days after acidification and filtration of aqueous solution of potassium salt of ketone (2, [K(HDTMone)·2H 2 O] n ). The stability of this novel gem-diol compound is found owning to the hydrogen bonds with lattice water molecules and electrophilic tetrazolyl groups. Meanwhile, the undissolved ketone (3, H 2 DTMone) was separated during the filtration in the process of gem-diol compound production. Surprisingly, the crystal-to-crystal perfect transition phenomena from gem-diol (1) to ketone (3) were firstly observed after heating up to 120  ° C as evidenced by X-ray single crystal diffraction and powder X-ray diffraction. These results found here might open new revenues for methylene oxidation and alkanediol chemistry.

  4. Aquifer Recharge and Watershed Response to Climate Change in the Upper Umatilla River Subbasin Using the Precipitation Runoff Modeling System

    Science.gov (United States)

    Yazzie, K.

    2014-12-01

    Groundwater recharge in the Columbia River Basalt Group (CRBG) in the Umatilla River Basin, OR, is poorly understood. The long-term decline of groundwater storage in the basalt aquifers, present a serious environmental challenge for the Confederated Tribes of the Umatilla Indian Reservation (CTUIR). This study will provide a groundwater estimate to help CTUIR better understand the hydrologic budget and inform water management decisions for present and future needs. The study site is in the upper Umatilla River Subbasin in Northeastern Oregon with an area that is 2,365 km2. The Precipitation Runoff Modeling System (PRMS) developed by the U.S. Geological Survey (USGS) is a distributed-parameter, physical-process watershed model that will be used to calculate groundwater recharge and simulate the watershed response to different climate and land use scenarios (Markstrom, 2008). The response of the hydrologic regime to climate change in the 2050s and 2080s will be determined using three downscaled Global Climate Models (GCMs), including the Earth System model of the Hadley Centre Global Environment Model, Version 2 (HadGEM2-ES), Model for Interdisciplinary Research on Climate (MIROC5), and the Geophysical Fluid Dynamics Laboratory - Earth System Model, (GFDL-ESM2M). The relationships between hydrologic processes at the surface, soil-zone, subsurface and groundwater reservoirs will be studied and defined in a water budget analysis to characterize the hydrologic regime in response to climate change.

  5. Financial recognition of material misstatement risks of listed companies on GEM

    OpenAIRE

    Jie Ming; Yicong Jiang

    2017-01-01

    Listed companies on GEM are characterized by strong innovation, great growth ability, high risks and high yields. Starting from these characteristics, this paper carries out analysis by using the financial indicators that are effective to recognize the material misstatement risks and easy to be acquired, and combines with the sample data with high material misstatement risks on GEM in 2012 to 2014 to test the significance of spss difference, and finds that the material misstatement company an...

  6. BoNuS: Development and Use of a Radial TPC using Cylindrical GEMs

    Energy Technology Data Exchange (ETDEWEB)

    Howard Fenker; Nathan Baillie; Peter Bradshaw; S. Bultmann; Stephen Bueltmann; Volker Burkert; Michael Christy; Gail Dodge; Dipangkar Dutta; Rolf Ent; Josh Evans; Robert Fersch; Kevin Giovanetti; Keith Griffioen; Mikayel Ispiryan; Chandana Jayalath; Narbe Kalantarians; Cynthia Keppel; Sebastian Kuhn; Gabriel Niculescu; Maria-Ioana Niculescu; Svyatoslav Tkachenko; Vladas Tvaskis; Jixie Zhang

    2007-11-28

    To provide new access to information about nucleon structure from electron-neutron interactions, a specialized aystem of target and detector was developed at Jefferson Lab. It allows identification and measurement of spectator protons produced in e X scattering events. The detector is a radial time-projection chamber optimized for the acceptance of low-momentum protons. Gas gain is provided by three cascaded curved Gas Electron Multipliers (GEMs), the first application of GEMs in any configuration other than flat.

  7. The application of a monolithic triphenylphosphine reagent for conducting Ramirez gem-dibromoolefination reactions in flow.

    Science.gov (United States)

    Roper, Kimberley A; Berry, Malcolm B; Ley, Steven V

    2013-01-01

    The application of a monolithic form of triphenylphosphine to the Ramirez gem-dibromoolefination reaction using flow chemistry techniques is reported. A variety of gem-dibromides were synthesised in high purity and excellent yield following only removal of solvent and no further off-line purification. It is also possible to perform the Appel reaction using the same monolith and the relationship between the mechanisms of the two reactions is discussed.

  8. The application of a monolithic triphenylphosphine reagent for conducting Ramirez gem-dibromoolefination reactions in flow

    Directory of Open Access Journals (Sweden)

    Kimberley A. Roper

    2013-09-01

    Full Text Available The application of a monolithic form of triphenylphosphine to the Ramirez gem-dibromoolefination reaction using flow chemistry techniques is reported. A variety of gem-dibromides were synthesised in high purity and excellent yield following only removal of solvent and no further off-line purification. It is also possible to perform the Appel reaction using the same monolith and the relationship between the mechanisms of the two reactions is discussed.

  9. Executive Information Systems' Multidimensional Models

    Directory of Open Access Journals (Sweden)

    2007-01-01

    Full Text Available Executive Information Systems are design to improve the quality of strategic level of management in organization through a new type of technology and several techniques for extracting, transforming, processing, integrating and presenting data in such a way that the organizational knowledge filters can easily associate with this data and turn it into information for the organization. These technologies are known as Business Intelligence Tools. But in order to build analytic reports for Executive Information Systems (EIS in an organization we need to design a multidimensional model based on the business model from the organization. This paper presents some multidimensional models that can be used in EIS development and propose a new model that is suitable for strategic business requests.

  10. Numerical Modeling of Microelectrochemical Systems

    DEFF Research Database (Denmark)

    Adesokan, Bolaji James

    for the reactants in the bulk electrolyte that are traveling waves. The first paper presents the mathematical model which describes an electrochemical system and simulates an electroanalytical technique called cyclic voltammetry. The model is governed by a system of advection–diffusion equations with a nonlinear...... reaction term at the boundary. We investigate the effect of flow rates, scan rates, and concentration on the cyclic voltammetry. We establish that high flow rates lead to the reduced hysteresis in the cyclic voltammetry curves and increasing scan rates lead to more pronounced current peaks. The final part...... of the paper shows that the response current in a cyclic voltammetry increases proportionally to the electrolyte concentration. In the second paper we present an experiment of an electrochemical system in a microfluidc system and compare the result to the numerical solutions. We investigate how the position...

  11. System Code Models and Capabilities

    International Nuclear Information System (INIS)

    Bestion, D.

    2008-01-01

    System thermalhydraulic codes such as RELAP, TRACE, CATHARE or ATHLET are now commonly used for reactor transient simulations. The whole methodology of code development is described including the derivation of the system of equations, the analysis of experimental data to obtain closure relation and the validation process. The characteristics of the models are briefly presented starting with the basic assumptions, the system of equations and the derivation of closure relationships. An extensive work was devoted during the last three decades to the improvement and validation of these models, which resulted in some homogenisation of the different codes although separately developed. The so called two-fluid model is the common basis of these codes and it is shown how it can describe both thermal and mechanical nonequilibrium. A review of some important physical models allows to illustrate the main capabilities and limitations of system codes. Attention is drawn on the role of flow regime maps, on the various methods for developing closure laws, on the role of interfacial area and turbulence on interfacial and wall transfers. More details are given for interfacial friction laws and their relation with drift flux models. Prediction of chocked flow and CFFL is also addressed. Based on some limitations of the present generation of codes, perspectives for future are drawn.

  12. [Construction of Lactobacillus rhamnosus GG particles surface display system].

    Science.gov (United States)

    Su, Runyu; Nie, Boyao; Yuan, Shengling; Tao, Haoxia; Liu, Chunjie; Yang, Bailiang; Wang, Yanchun

    2017-01-25

    To describe a novel particles surface display system which is consisted of gram-positive enhancer matrix (GEM) particles and anchor proteins for bacteria-like particles vaccines, we treated Lactobacillus rhamnosus GG bacteria with 10% heated-TCA for preparing GEM particles, and then identified the harvested GEM particles by electron microscopy, RT-PCR and SDS-PAGE. Meanwhile, Escherichia coli was induced to express hybrid proteins PA3-EGFP and P60-EGFP, and GEM particles were incubated with them. Then binding of anchor proteins were determined by Western blotting, transmission electron microscopy, fluorescence microscopy and spectrofluorometry. GEM particles preserved original size and shape, and proteins and DNA contents of GEM particles were released substantially. The two anchor proteins both had efficiently immobilized on the surface of GEM. GEM particles that were bounded by anchor proteins were brushy. The fluorescence of GEM particles anchoring PA3 was slightly brighter than P60, but the difference was not significant (P>0.05). GEM particles prepared from L. rhamnosus GG have a good binding efficiency with anchor proteins PA3-EGFP and P60-EGFP. Therefore, this novel foreign protein surface display system could be used for bacteria-like particle vaccines.

  13. Experimental Modeling of Dynamic Systems

    DEFF Research Database (Denmark)

    Knudsen, Morten Haack

    2006-01-01

    An engineering course, Simulation and Experimental Modeling, has been developed that is based on a method for direct estimation of physical parameters in dynamic systems. Compared with classical system identification, the method appears to be easier to understand, apply, and combine with physical...... insight. It is based on a sensitivity approach that is useful for choice of model structure, for experiment design, and for accuracy verification. The method is implemented in the Matlab toolkit Senstools. The method and the presentation have been developed with generally preferred learning styles in mind...

  14. Compositional Modeling of Biological Systems

    OpenAIRE

    Zámborszky, Judit

    2010-01-01

    Molecular interactions are wired in a fascinating way resulting in complex behavior of bio-logical systems. Theoretical modeling provides us a useful framework for understanding the dynamics and the function of such networks. The complexity of the biological systems calls for conceptual tools that manage the combinatorial explosion of the set of possible interac-tions. A suitable conceptual tool to attack complexity is compositionality, already success-fully used in the process algebra field ...

  15. Characterization of the allergen Sol gem 2 from the fire ant venom, Solenopsis geminata

    Directory of Open Access Journals (Sweden)

    S Sukprasert

    2012-01-01

    Full Text Available Sol i 2 is a potent allergen in Solenopsis invicta venom, and most humans exhibit reactivity to it. The Sol gem 2 allergen found in the venom of the Thai tropical fire ant Solenopsis geminata was analysed in the present study. The protein was present in higher amounts than other proteins, as determined by SDS-PAGE, and presumably has allergenic properties similar to those of Sol i 2. Sol gem 2 molecular weight is 28 and 15 kDa, respectively, under non-reducing and reducing conditions, indicating that its native form is a dimer. LC-MS/MS analysis confirmed its similarity to Sol i 2. The mono/dimeric form of Sol gem 2 was determined to be relevant by proteomic approach and immunoblotting. An anti-Sol gem 2 antibody was produced in mice, with a titer greater than 1:800 according to the Western blotting analysis. The Sol gem 2-neutralising activity of this antibody was determined in crickets. The paralytic dose 50 (PD50 of crude S. geminata venom was elevated from 0.18 mg/g of body weight to more than 0.90 mg/g of body weight after preincubation with antibody at a ratio of 1:1. These results suggest that Sol gem 2 plays an important role in mediating the effects of the piperidine derivatives in the venom.

  16. Parametric Modeling for Fluid Systems

    Science.gov (United States)

    Pizarro, Yaritzmar Rosario; Martinez, Jonathan

    2013-01-01

    Fluid Systems involves different projects that require parametric modeling, which is a model that maintains consistent relationships between elements as is manipulated. One of these projects is the Neo Liquid Propellant Testbed, which is part of Rocket U. As part of Rocket U (Rocket University), engineers at NASA's Kennedy Space Center in Florida have the opportunity to develop critical flight skills as they design, build and launch high-powered rockets. To build the Neo testbed; hardware from the Space Shuttle Program was repurposed. Modeling for Neo, included: fittings, valves, frames and tubing, between others. These models help in the review process, to make sure regulations are being followed. Another fluid systems project that required modeling is Plant Habitat's TCUI test project. Plant Habitat is a plan to develop a large growth chamber to learn the effects of long-duration microgravity exposure to plants in space. Work for this project included the design and modeling of a duct vent for flow test. Parametric Modeling for these projects was done using Creo Parametric 2.0.

  17. Model checking embedded system designs

    NARCIS (Netherlands)

    Brinksma, Hendrik; Mader, Angelika H.

    2002-01-01

    Model checking has established itself as a successful tool supported technique for the verification and debugging of various hardware and software systems [16]. Not only in academia, but also by industry this technique is increasingly being regarded as a promising and practical proposition,

  18. GENERIC model for multiphase systems

    NARCIS (Netherlands)

    Sagis, L.M.C.

    2010-01-01

    GENERIC is a nonequilibrium thermodynamic formalism in which the dynamic behavior of a system is described by a single compact equation involving two types of brackets: a Poisson bracket and a dissipative bracket. This formalism has proved to be a very powerful instrument to model the dynamic

  19. An extensible analysable system model

    DEFF Research Database (Denmark)

    Probst, Christian W.; Hansen, Rene Rydhof

    2008-01-01

    Analysing real-world systems for vulnerabilities with respect to security and safety threats is a difficult undertaking, not least due to a lack of availability of formalisations for those systems. While both formalisations and analyses can be found for artificial systems such as software......, this does not hold for real physical systems. Approaches such as threat modelling try to target the formalisation of the real-world domain, but still are far from the rigid techniques available in security research. Many currently available approaches to assurance of critical infrastructure security...... are based on (quite successful) ad-hoc techniques. We believe they can be significantly improved beyond the state-of-the-art by pairing them with static analyses techniques. In this paper we present an approach to both formalising those real-world systems, as well as providing an underlying semantics, which...

  20. Systems modeling for laser IFE

    Science.gov (United States)

    Meier, W. R.; Raffray, A. R.; Sviatoslavsky, I. N.

    2006-06-01

    A systems model of a laser-driven IFE power plant is being developed to assist in design trade-offs and optimization. The focus to date has been on modeling the fusion chamber, blanket and power conversion system. A self-consistent model has been developed to determine key chamber and thermal cycle parameters (e.g., chamber radius, structure and coolant temperatures, cycle efficiency, etc.) as a function of the target yield and pulse repetition rate. Temperature constraints on the tungsten armor, ferritic steel wall, and structure/coolant interface are included in evaluating the potential design space. Results are presented for a lithium cooled first wall coupled with a Brayton power cycle. LLNL work performed under the auspices of the US Department of Energy by the University of California LLNL under Contract W-7405-Eng-48.

  1. Experiment study on the thick GEM-like multiplier for X-ray photoelectrons energy deposition gaining

    International Nuclear Information System (INIS)

    Zhu Pengfei; Ye Yan; Long Yan; Cao Ningxiang; Jia Xing; Li Jianfeng

    2009-01-01

    The GEM is a novel detector with high gain,high time and location resolution. Imitating the structure of the GEM, a thick GEM-like multiplier which has the similar function with that of the GEM is designed and manufactured. The characteristics of the thick GEM-like multiplier increasing electron energy deposition in absorbing medium has been experimentally studied. The results indicate that the energy deposition gain of x-ray photoelectron in medium is apparent, and the maximum energy deposition can increase by more than 40%. Some suggestions of further increasing the energy deposition are given, and the future application of the way of increasing the x-ray photoelectron energy deposition by the thick GEM-like multiplier in hard x-ray imaging is prospected. (authors)

  2. Cotangent Models for Integrable Systems

    Science.gov (United States)

    Kiesenhofer, Anna; Miranda, Eva

    2017-03-01

    We associate cotangent models to a neighbourhood of a Liouville torus in symplectic and Poisson manifolds focusing on b-Poisson/ b-symplectic manifolds. The semilocal equivalence with such models uses the corresponding action-angle theorems in these settings: the theorem of Liouville-Mineur-Arnold for symplectic manifolds and an action-angle theorem for regular Liouville tori in Poisson manifolds (Laurent- Gengoux et al., IntMath Res Notices IMRN 8: 1839-1869, 2011). Our models comprise regular Liouville tori of Poisson manifolds but also consider the Liouville tori on the singular locus of a b-Poisson manifold. For this latter class of Poisson structures we define a twisted cotangent model. The equivalence with this twisted cotangent model is given by an action-angle theorem recently proved by the authors and Scott (Math. Pures Appl. (9) 105(1):66-85, 2016). This viewpoint of cotangent models provides a new machinery to construct examples of integrable systems, which are especially valuable in the b-symplectic case where not many sources of examples are known. At the end of the paper we introduce non-degenerate singularities as lifted cotangent models on b-symplectic manifolds and discuss some generalizations of these models to general Poisson manifolds.

  3. Muon Chamber Endcap Upgrade of the CMS Experiment with Gas Electron Multiplier (GEM) Detectors and their Performance

    CERN Document Server

    Gola, Mohit

    2017-01-01

    As the CERN LHC is heading towards a high luminosity phase a very high flux is expected in the endcaps of the CMS Detector. The presence of muons in collision events can be due to rare or new physics so it is important to maintain the high trigger efficiency of the CMS muon system. The CMS Collaboration has proposed to instrument the high-eta region (1.6 lt IetaI lt 2.2) of the muon endcaps with Gas Electron Multiplier (GEM) detectors, referred to as GE1/1 chambers, during the LS2. This technology will help in maintaining optimum trigger performance with maximum selection efficiency of muons even in a high flux environment. We describe plans for a Slice Test to installa few GE1/1 chambers covering 50 degrees in azimuthal angle within the CMS detector in 2017, with subsequent operation during the current Run 2 of the LHC. We show the performance of the GE1/1 chambers to be installed during the slice test, specifically GEM foil leakage currents, chamber gas volume integrity, high voltage circuit performanc...

  4. A GEM-TPC prototype with low-Noise highly integrated front-end electronics for linear collider studies

    CERN Document Server

    Kappler, Steffen; Kaminski, Jochen; Ledermann, Bernhard; Müller, Thomas; Ronan, Michael T; Ropelewski, Leszek; Sauli, Fabio; Settles, Ronald

    2004-01-01

    Connected to the linear collider project, studies on the readout of time projection chambers (TPCs) based on the gas electron multiplier (GEM) are ongoing. Higher granularity and intrinsically suppressed ion feedback are the major advantages of this technology. After a short discussion of these issues, we present the design of a small and very flexible TPC prototype, whose cylindrical drift volume can be equipped with endcaps of different gas detector types. An endcap with multi-GEM readout is currently set up and successfully operated with a low-noise highly integrated front-end electronics. We discuss results of measurements with this system in high intensity particle beams at CERN, where 99.3 plus or minus 0.2% single-pad-row efficiency could be achieved at an effective gain of 2.5 multiplied by 10**3 only, and spatial resolutions down to 63 plus or minus 3 mum could be demonstrated. Finally, these results are extrapolated to the high magnetic field in a linear collider TPC. 5 Refs.

  5. Graph modeling systems and methods

    Science.gov (United States)

    Neergaard, Mike

    2015-10-13

    An apparatus and a method for vulnerability and reliability modeling are provided. The method generally includes constructing a graph model of a physical network using a computer, the graph model including a plurality of terminating vertices to represent nodes in the physical network, a plurality of edges to represent transmission paths in the physical network, and a non-terminating vertex to represent a non-nodal vulnerability along a transmission path in the physical network. The method additionally includes evaluating the vulnerability and reliability of the physical network using the constructed graph model, wherein the vulnerability and reliability evaluation includes a determination of whether each terminating and non-terminating vertex represents a critical point of failure. The method can be utilized to evaluate wide variety of networks, including power grid infrastructures, communication network topologies, and fluid distribution systems.

  6. Radiation tests for a single-GEM-loaded gaseous detector

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Kyong Sei; Hong, Byung Sik; Park, Sung Keun [Korea University, Seoul (Korea, Republic of); Kim, Sang Yeol [NoticeKorea, Anyang (Korea, Republic of)

    2014-11-15

    We report on a systematic study of a single-gas-electron-multiplier (GEM)-loaded gaseous detector developed for precision measurements of high-energy particle beams and for dose verification in particle therapy. In the present study, a 256-channel prototype detector having an active area of 16 x 16 cm{sup 2} and operating using a continuous current-integration-mode signal-processing method was manufactured and tested with X-rays emitted from a 70-kV X-ray generator and 43-MeV protons provided by the MC50 proton cyclotron at the Korea Institute of Radiological and Medical Science(KIRAMS). The amplified detector response was measured for X-rays with an intensity of about 5 x 10{sup 6} Hz cm{sup -2}. The linearity of the detector response to the particle flux was examined and validated by using 43-MeV proton beams. The non-uniform development of the amplification for the gas electrons in space was corrected by applying a proper calibration to the channel responses of the measured beam-profile data. We conclude from the radiation tests that the detector developed in the present study will allow us to perform quality measurements of various high-energy particle beams and to apply the technology to dose-verification measurements in particle therapy.

  7. Probabilistic models for feedback systems.

    Energy Technology Data Exchange (ETDEWEB)

    Grace, Matthew D.; Boggs, Paul T.

    2011-02-01

    In previous work, we developed a Bayesian-based methodology to analyze the reliability of hierarchical systems. The output of the procedure is a statistical distribution of the reliability, thus allowing many questions to be answered. The principal advantage of the approach is that along with an estimate of the reliability, we also can provide statements of confidence in the results. The model is quite general in that it allows general representations of all of the distributions involved, it incorporates prior knowledge into the models, it allows errors in the 'engineered' nodes of a system to be determined by the data, and leads to the ability to determine optimal testing strategies. In this report, we provide the preliminary steps necessary to extend this approach to systems with feedback. Feedback is an essential component of 'complexity' and provides interesting challenges in modeling the time-dependent action of a feedback loop. We provide a mechanism for doing this and analyze a simple case. We then consider some extensions to more interesting examples with local control affecting the entire system. Finally, a discussion of the status of the research is also included.

  8. A study of the effect of non-spherical dust particles on Geostationary Environment Monitoring Spectrometer (GEMS) aerosol optical properties retrievals

    Science.gov (United States)

    Go, S.; Kim, J.; KIM, M.; Choi, M.; Lim, H.

    2017-12-01

    Non-spherical assumption of particle shape has been used to replace the spherical assumption in the Geostationary Environment Monitoring Spectrometer (GEMS) aerosol optical properties retrievals for dust particles. GEMS aerosol retrieval algorithms are based on optimal estimation method to provide aerosol optical depth (AOD), single scattering albedo (SSA) at 443nm, and aerosol loading height (ALH) simultaneously as products. Considering computing time efficiency, the algorithm takes Look-Up Table (LUT) approach using Vector Linearized Discrete Ordinate Radiative Transfer code (VLIDORT), and aerosol optical properties for three aerosol types of absorbing fine aerosol (BC), dust and non-absorbing aerosol (NA) are integrated from AERONET inversion data, and fed into the LUT calculation. In this study, by applying the present algorithm to OMI top-of the atmosphere normalized radiance, retrieved AOD, SSA with both spherical and non-spherical assumptions have been compared to the surface AERONET observations at East Asia sites for 3 years from 2005 to 2007 to evaluate and quantify the effect of non-spherical dust particles on the satellite aerosol retrievals. The root-mean-square error (RMSE) in the satellite retrieved AOD have been slightly reduced as a result of adopting the non-spherical assumption in the GEMS aerosol retrieval algorithm. For SSA, algorithm tested with spheroid models on dust particle shows promising results for the improved SSA. In terms of ALH, the results are qualitatively compared with CALIOP products, and shows consistent variation. This result suggests the importance of taking into account the effects of non-sphericity in the retrieval of dust particles from GEMS measurements.

  9. ESTADO DE LA EDUCACIÓN Y FORMACIÓN EMPRESARIAL EN LOS PAÍSES Y REGIONES ESPAÑOLAS DEL GEM

    Directory of Open Access Journals (Sweden)

    Ana Fernández Laviada

    2014-12-01

    Full Text Available Specialised literature presents education and training as a determining factor for entrepreneurship. However, time and time again experts at the Global Entrepreneurship Monitor (GEM have stated that it’s one lowest, and sometimes the least, valued elements in this area. Therefore, the objective of this study is to analyse the state of entrepreneurship education and training in its different stages within the countries and regions that participated in GEM 2012. Specifically, what is sought is, based on the opinion of the experts, the state of entrepreneurship training and education in each level analysed in GEM, generically as well as by country, while looking at the possible differences (strengths and weaknesses that appear in each one. Furthermore, this is paired with a national analysis that examines the situation of the different participating regions in the study. In order to carry out the analysis, the 2012 NES database is used. In that edition, a total of 69 countries participated and, in the case of Spain, there were 14 regions all with 36 experts in each. The data processing is carried out using the Rasch model for measurement. The preliminary results show that, in general, university level education geared towards entrepreneurship is more highly developed than at the lower levels of education, such as in secondary and primary education. Nevertheless, the individual analysis makes it possible to detect differences between countries and regions.

  10. Stochastic Modelling of Hydrologic Systems

    DEFF Research Database (Denmark)

    Jonsdottir, Harpa

    2007-01-01

    In this PhD project several stochastic modelling methods are studied and applied on various subjects in hydrology. The research was prepared at Informatics and Mathematical Modelling at the Technical University of Denmark. The thesis is divided into two parts. The first part contains an introduct......In this PhD project several stochastic modelling methods are studied and applied on various subjects in hydrology. The research was prepared at Informatics and Mathematical Modelling at the Technical University of Denmark. The thesis is divided into two parts. The first part contains...... an introduction and an overview of the papers published. Then an introduction to basic concepts in hydrology along with a description of hydrological data is given. Finally an introduction to stochastic modelling is given. The second part contains the research papers. In the research papers the stochastic methods...... are described, as at the time of publication these methods represent new contribution to hydrology. The second part also contains additional description of software used and a brief introduction to stiff systems. The system in one of the papers is stiff....

  11. Discrete modelling of drapery systems

    Science.gov (United States)

    Thoeni, Klaus; Giacomini, Anna

    2016-04-01

    Drapery systems are an efficient and cost-effective measure in preventing and controlling rockfall hazards on rock slopes. The simplest form consists of a row of ground anchors along the top of the slope connected to a horizontal support cable from which a wire mesh is suspended down the face of the slope. Such systems are generally referred to as simple or unsecured draperies (Badger and Duffy 2012). Variations such as secured draperies, where a pattern of ground anchors is incorporated within the field of the mesh, and hybrid systems, where the upper part of an unsecured drapery is elevated to intercept rockfalls originating upslope of the installation, are becoming more and more popular. This work presents a discrete element framework for simulation of unsecured drapery systems and its variations. The numerical model is based on the classical discrete element method (DEM) and implemented into the open-source framework YADE (Šmilauer et al., 2010). The model takes all relevant interactions between block, drapery and slope into account (Thoeni et al., 2014) and was calibrated and validated based on full-scale experiments (Giacomini et al., 2012).The block is modelled as a rigid clump made of spherical particles which allows any shape to be approximated. The drapery is represented by a set of spherical particle with remote interactions. The behaviour of the remote interactions is governed by the constitutive behaviour of the wire and generally corresponds to a piecewise linear stress-strain relation (Thoeni et al., 2013). The same concept is used to model wire ropes. The rock slope is represented by rigid triangular elements where material properties (e.g., normal coefficient of restitution, friction angle) are assigned to each triangle. The capabilities of the developed model to simulate drapery systems and estimate the residual hazard involved with such systems is shown. References Badger, T.C., Duffy, J.D. (2012) Drapery systems. In: Turner, A.K., Schuster R

  12. An efficient and general route to gem-difluoromethylenated alpha,beta-unsaturated delta-lactones: high enantioselective synthesis of gem-difluoromethylenated goniothalamins.

    Science.gov (United States)

    You, Zheng-Wei; Jiang, Zhong-Xing; Wang, Bing-Lin; Qing, Feng-Ling

    2006-09-15

    An efficient and general strategy to gem-difluoromethylenated alpha,beta-unsaturated delta-lactones in high yields from various aldehydes (including aliphatic, aromatic, alpha,beta-unsaturated, and sterically hindered aldehydes) has been developed. This methodology was successfully applied for the preparation of two enantiomers of gem-difluoromethylenated goniothalamins (S)-1 and (R)-1. gem-Difluoropropargylation of cinnamaldehyde followed by the resolution of resulting homopropargylic alcohols mediated by lipase from Pseudomonas (AK) gave alcohols (R)-6 and (S)-6. Selective hydrogenation of the triple bond of (S)-6 and (R)-6 to double bond with Lindlar catalyst in the presence of quinoline afforded the expected product (S)-8 and (R)-8, respectively. Deprotection of (S)-8 and (R)-8 followed by oxidation of the resulting 1,5-diols with catalytic 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO) and excess bis-acetoxyiodobenzene (BAIB) provided the target molecules gem-difluoromethylenated goniothalamins (S)-1 and (R)-1 in high yields, respectively.

  13. J-GEM observations of an electromagnetic counterpart to the neutron star merger GW170817

    Science.gov (United States)

    Utsumi, Yousuke; Tanaka, Masaomi; Tominaga, Nozomu; Yoshida, Michitoshi; Barway, Sudhanshu; Nagayama, Takahiro; Zenko, Tetsuya; Aoki, Kentaro; Fujiyoshi, Takuya; Furusawa, Hisanori; Kawabata, Koji S.; Koshida, Shintaro; Lee, Chien-Hsiu; Morokuma, Tomoki; Motohara, Kentaro; Nakata, Fumiaki; Ohsawa, Ryou; Ohta, Kouji; Okita, Hirofumi; Tajitsu, Akito; Tanaka, Ichi; Terai, Tsuyoshi; Yasuda, Naoki; Abe, Fumio; Asakura, Yuichiro; Bond, Ian A.; Miyazaki, Shota; Sumi, Takahiro; Tristram, Paul J.; Honda, Satoshi; Itoh, Ryosuke; Itoh, Yoichi; Kawabata, Miho; Morihana, Kumiko; Nagashima, Hiroki; Nakaoka, Tatsuya; Ohshima, Tomohito; Takahashi, Jun; Takayama, Masaki; Aoki, Wako; Baar, Stefan; Doi, Mamoru; Finet, Francois; Kanda, Nobuyuki; Kawai, Nobuyuki; Kim, Ji Hoon; Kuroda, Daisuke; Liu, Wei; Matsubayashi, Kazuya; Murata, Katsuhiro L.; Nagai, Hiroshi; Saito, Tomoki; Saito, Yoshihiko; Sako, Shigeyuki; Sekiguchi, Yuichiro; Tamura, Yoichi; Tanaka, Masayuki; Uemura, Makoto; Yamaguchi, Masaki S.

    2017-12-01

    GW170817 is the first detected gravitational wave source from a neutron star merger. We present the Japanese collaboration for gravitational-wave electro-magnetic (J-GEM) follow-up observations of SSS17a, an electromagnetic counterpart of GW170817. SSS17a shows a 2.5 mag decline in the z band during the period between 1.7 and 7.7 d after the merger. Such a rapid decline is not comparable with supernovae light curves at any epoch. The color of SSS17a also evolves rapidly and becomes redder during later epochs: the z - H color has changed by approximately 2.5 mag during the period between 0.7 and 7.7 d. The rapid evolutions of both the color and the optical brightness are consistent with the expected properties of a kilonova that is powered by the radioactive decay of newly synthesized r-process nuclei. Kilonova models with Lanthanide elements can reproduce the aforementioned observed properties well, which suggests that r-process nucleosynthesis beyond the second peak takes place in SSS17a. However, the absolute magnitude of SSS17a is brighter than the expected brightness of the kilonova models with an ejecta mass of 0.01 M⊙, which suggests a more intense mass ejection (˜0.03 M⊙) or possibly an additional energy source.

  14. Generation of an atlas for commodity chemical production in Escherichia coli and a novel pathway prediction algorithm, GEM-Path

    DEFF Research Database (Denmark)

    Campodonico, Miguel A.; Andrews, Barbara A.; Asenjo, Juan A.

    2014-01-01

    , a pathway prediction algorithm that combines direct integration of genome-scale models at each step of the search to reduce the search space does not exist. Previous work (Feist. el. al., 2010) performed a model driven evaluation of the growth coupled production potential for E. call to produce multiple...... native compounds from different feedstocks. In this study, we extended this analysis for non-native compounds by using an integrated approach through heterologous pathway integration and growth coupled metabolite production design. In addition to integration with genome-scale model integration, the GEM...... Path algorithm developed in this work also contains a novel approach to address reaction promiscuity. In total, 245 unique synthetic pathways for 20 large volume compounds were predicted. Host metabolism with these synthetic pathways was then analyzed for feasible growth-coupled production and designs...

  15. Computational models of complex systems

    CERN Document Server

    Dabbaghian, Vahid

    2014-01-01

    Computational and mathematical models provide us with the opportunities to investigate the complexities of real world problems. They allow us to apply our best analytical methods to define problems in a clearly mathematical manner and exhaustively test our solutions before committing expensive resources. This is made possible by assuming parameter(s) in a bounded environment, allowing for controllable experimentation, not always possible in live scenarios. For example, simulation of computational models allows the testing of theories in a manner that is both fundamentally deductive and experimental in nature. The main ingredients for such research ideas come from multiple disciplines and the importance of interdisciplinary research is well recognized by the scientific community. This book provides a window to the novel endeavours of the research communities to present their works by highlighting the value of computational modelling as a research tool when investigating complex systems. We hope that the reader...

  16. Model reduction of parametrized systems

    CERN Document Server

    Ohlberger, Mario; Patera, Anthony; Rozza, Gianluigi; Urban, Karsten

    2017-01-01

    The special volume offers a global guide to new concepts and approaches concerning the following topics: reduced basis methods, proper orthogonal decomposition, proper generalized decomposition, approximation theory related to model reduction, learning theory and compressed sensing, stochastic and high-dimensional problems, system-theoretic methods, nonlinear model reduction, reduction of coupled problems/multiphysics, optimization and optimal control, state estimation and control, reduced order models and domain decomposition methods, Krylov-subspace and interpolatory methods, and applications to real industrial and complex problems. The book represents the state of the art in the development of reduced order methods. It contains contributions from internationally respected experts, guaranteeing a wide range of expertise and topics. Further, it reflects an important effor t, carried out over the last 12 years, to build a growing research community in this field. Though not a textbook, some of the chapters ca...

  17. Modeling software systems by domains

    Science.gov (United States)

    Dippolito, Richard; Lee, Kenneth

    1992-01-01

    The Software Architectures Engineering (SAE) Project at the Software Engineering Institute (SEI) has developed engineering modeling techniques that both reduce the complexity of software for domain-specific computer systems and result in systems that are easier to build and maintain. These techniques allow maximum freedom for system developers to apply their domain expertise to software. We have applied these techniques to several types of applications, including training simulators operating in real time, engineering simulators operating in non-real time, and real-time embedded computer systems. Our modeling techniques result in software that mirrors both the complexity of the application and the domain knowledge requirements. We submit that the proper measure of software complexity reflects neither the number of software component units nor the code count, but the locus of and amount of domain knowledge. As a result of using these techniques, domain knowledge is isolated by fields of engineering expertise and removed from the concern of the software engineer. In this paper, we will describe kinds of domain expertise, describe engineering by domains, and provide relevant examples of software developed for simulator applications using the techniques.

  18. A triple GEM detector with pad readout for high rate charged particle triggering

    Energy Technology Data Exchange (ETDEWEB)

    Bencivenni, G.; Felici, G.; Murtas, F.; Valente, P.; Bonivento, W. E-mail: walter.bonivento@cern.ch; Cardini, A.; Lai, A.; Pinci, D.; Saitta, B.; Bosio, C

    2002-08-11

    In this paper, results of a time performance study of triple gas electron multiplier (GEM) detectors are discussed. This study was driven by an R and D activity on detectors for the Level 0 LHCb muon trigger. However, the results presented in this paper are of more general interest, i.e. for experiments with high rate charged particle triggering. Little interest was given so far to time performance of GEM detectors. Only one group measured double GEM detector time resolution with the Ar/CO{sub 2} (70/30) gas mixture. Our study aimed at triple GEM detector optimisation for good time performance through a detailed investigation of the role played by detector geometry, electric fields and gas mixture. The results reported here, in particular when using the gas mixture Ar/CO{sub 2}/CF{sub 4} (60/20/20), considerably improve the time performance discussed in the above-mentioned paper and make the triple GEM detector a promising option for high rate charged particle triggering.

  19. Evaluation of the optimum induction gap for the GEM-MIGAS

    International Nuclear Information System (INIS)

    Mir, J.A.; Rhodes, N.J.; Schooneveld, E.M.; Conceicao, A.S.; Maia, J.M.; Veloso, J.F.C.A.; dos Santos, J.M.F.

    2009-01-01

    A gas electron multiplier with a micro-induction gap amplifying structure (GEM-MIGAS) is formed when a conventional GEM is operated with a short induction gap, typically set at 50 μm. The main aims of this study were to examine the charge amplification in the induction gap of the GEM-MIGAS and then to evaluate the optimum induction gap thickness for achieving the maximum charge amplification in the region. For the present study, the GEM-MIGAS was operated in the gas flow mode using He/iso-C 4 H 10 (85/15%). It was also possible to determine the optimum gap thickness, where the dependence of the charge amplification was least sensitive to the small variations of the gap thickness and to the ambient variables, such as pressure and temperature. This was accomplished by setting the voltage across the GEM-holes to a small value as to allow the transfer of electrons from the drift region into the induction region, without incurring multiplication within the holes. Through parametric curve fitting of the charge gain-induction gap voltage characteristics, the optimum induction gap for sustaining highest charge gains was evaluated and compared with trends observed using a conventional Micromegas.

  20. Applications of Mapping and Tomographic Techniques in Gem Sciences

    Science.gov (United States)

    Shen, A. H.

    2014-12-01

    Gem Sciences are scientific studies of gemstones - their genesis, provenance, synthesis, enhancement, treatment and identification. As high quality forms of specific minerals, the gemstones exhibit unusual physical properties that are usually unseen in the regular counterparts. Most gemstones are colored by trace elements incorporated in the crystal lattice during various growth stages; forming coloration zones of various scales. Studying the spectral and chemical contrast across color zones helps elucidating the origins of colors. These are done by UV-visible spectrometers with microscope and LA-ICPMS in modern gemological laboratories. In the case of diamonds, their colored zones arise from various structural defects incorporated in different growth zones and are studied with FTIR spectrometers with IR microscope and laser photoluminescence spectrometers. Advancement in modern synthetic techniques such as chemical vapor deposition (CVD) has created some problem for identification. Some exploratory experiments in carbon isotope mapping were done on diamonds using SIMS. The most important issue in pearls is to identify one particular pearl being a cultured one or a natural pearl. The price difference can be enormous. Classical way of such identification is done by x-ray radiographs, which clearly show the bead and the nacre. Modern cultured pearl advancement has eliminated the need for an artificial bead, but a small piece of tissue instead. Nowadays, computer x-ray tomography (CT) scanning devices are used to depict the clear image of the interior of a pearl. In the Chinese jade market, filling fissures with epoxy and/or wax are very commonly seen. We are currently exploring Magnetic Resonance Imaging (MRI) technique to map the distribution of artificial resin within a polycrystalline aggregates.

  1. A priori modeling of chemical reactions on computational grid platforms: Workflows and data models

    International Nuclear Information System (INIS)

    Rampino, S.; Monari, A.; Rossi, E.; Evangelisti, S.; Laganà, A.

    2012-01-01

    Graphical abstract: The quantum framework of the Grid Empowered Molecular Simulator GEMS assembled on the European Grid allows the ab initio evaluation of the dynamics of small systems starting from the calculation of the electronic properties. Highlights: ► The grid based GEMS simulator accurately models small chemical systems. ► Q5Cost and D5Cost file formats provide interoperability in the workflow. ► Benchmark runs on H + H 2 highlight the Grid empowering. ► O + O 2 and N + N 2 calculated k (T)’s fall within the error bars of the experiment. - Abstract: The quantum framework of the Grid Empowered Molecular Simulator GEMS has been assembled on the segment of the European Grid devoted to the Computational Chemistry Virtual Organization. The related grid based workflow allows the ab initio evaluation of the dynamics of small systems starting from the calculation of the electronic properties. Interoperability between computational codes across the different stages of the workflow was made possible by the use of the common data formats Q5Cost and D5Cost. Illustrative benchmark runs have been performed on the prototype H + H 2 , N + N 2 and O + O 2 gas phase exchange reactions and thermal rate coefficients have been calculated for the last two. Results are discussed in terms of the modeling of the interaction and advantages of using the Grid is highlighted.

  2. The GEM detectors for the innermost region of the forward muon station of the LHCb experiment

    CERN Document Server

    Alfonsi, M

    The LHCb experiment will take place at the LHC accelerator at CERN and will start in 2008. It is dedicated to precision measurements of CP violation and rare decays in the b quark sec- tor. The apparatus is a single arm spectrometer and it is designed with a robust and flexible trigger in order to extensively gain access to a wide spread of differ ent physical processes involving beauty particles. This will allow to over-constrain the Standard M odel predictions about CP violation, and to discover any possible inconsistency, whi ch would reveal the presence of “New Physics” beyond the Standard Model. This thesis reports the work performed on two aspects of the L HCb experiment: the main contribution is the development and the construction of a de tector based on Gas Electron Multiplier (GEM) technology for the instrumentation of the high irradiated region around the beam pipe of the forward Muon Station; in the second part t he possibility of the search of the rare D 0 → + − decay at the LHCb exper...

  3. Cognitive models embedded in system simulation models

    International Nuclear Information System (INIS)

    Siegel, A.I.; Wolf, J.J.

    1982-01-01

    If we are to discuss and consider cognitive models, we must first come to grips with two questions: (1) What is cognition; (2) What is a model. Presumably, the answers to these questions can provide a basis for defining a cognitive model. Accordingly, this paper first places these two questions into perspective. Then, cognitive models are set within the context of computer simulation models and a number of computer simulations of cognitive processes are described. Finally, pervasive issues are discussed vis-a-vis cognitive modeling in the computer simulation context

  4. Thermodynamic modeling of complex systems

    DEFF Research Database (Denmark)

    Liang, Xiaodong

    . Contrary to earlier theories, the oil is not only present on the surface, but also in great volumes both in the water column and on the seafloor, which indicates that we do not know enough about how oil behaves in water and interacts with it. Sonar detection is one of the most important and necessary...... after an oil spill. Engineering thermodynamics could be applied in the state-of-the-art sonar products through advanced artificial technology, if the speed of sound, solubility and density of oil-seawater systems could be satisfactorily modelled. The addition of methanol or glycols into unprocessed well...... streams during subsea pipelines is necessary to inhibit gas hydrate formation, and the offshore reservoirs often mean complicated temperature and pressure conditions. Accurate description of the phase behavior and thermalphysical properties of complex systems containing petroleum fluids and polar...

  5. Studies of Catalytic Model Systems

    DEFF Research Database (Denmark)

    Holse, Christian

    of the Cu/ZnO nanoparticles is highly relevant to industrial methanol synthesis for which the direct interaction of Cu and ZnO nanocrystals synergistically boost the catalytic activity. The dynamical behavior of the nanoparticles under reducing and oxidizing environments were studied by means of ex situ X...... as the nanoparticles are reduced. The Cu/ZnO nanoparticles are tested on a  µ-reactor platform and prove to be active towards methanol synthesis, making it an excellent model system for further investigations into activity depended morphology changes....

  6. Development of Large-Area GEM Detectors for the Forward Muon Endcap Upgrade of the CMS Experiment and Search for SM Higgs Boson Decay in the $H\\to\\tau^{+}\\tau^{-}\\to\\mu^{+}\\mu^{-}\\bar{\

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00366476; Gallo, Elisabetta; Raspereza, Alexei

    Gas Electron Multiplier (GEM) technology is being considered for the forward muon upgrade of the Compact Muon Solenoid (CMS) experiment in \\mbox{Phase II} of the CERN LHC. The first GEM Endcap (GE1/1) is going to be installed in the $1.5 < \\mid\\eta\\mid < 2.2$ region of the muon endcapˆ’ mainly to control muon level-1 trigger rates after the second long LHC shutdown. A GE1/1 triple-GEM detector is read out by 3,072 radial strips with 453 $\\mu$rad pitch arranged in eight $\\eta$-sectors. A meter-long GE1/1 prototype-III was assembled at Florida Tech and tested in 20-120 GeV hadron beams at Fermilab using Ar/CO$_{2}$ 70:30 and the RD51 Scalable Readout System (SRS). Four GEM detectors with 2-D readout and an average measured azimuthal resolution of 36$\\mu$rad provided precise reference tracks. Construction of this GE1/1 prototype-III detector and its performance in the test beam are described. Strip cluster parameters, detection efficiency, and spatial resolution are studied with position and high voltag...

  7. New paradigms for metabolic modeling of human cells

    DEFF Research Database (Denmark)

    Mardinoglu, Adil; Nielsen, Jens

    2015-01-01

    review recent work on reconstruction of GEMs for human cell/tissue types and cancer, and the use of GEMs for identification of metabolic changes occurring in response to disease development. We further discuss how GEMs can be used for the development of efficient therapeutic strategies. Finally......Abnormalities in cellular functions are associated with the progression of human diseases, often resulting in metabolic reprogramming. GEnome-scale metabolic Models (GEMs) have enabled studying global metabolic reprogramming in connection with disease development in a systematic manner. Here we...

  8. Analysis of parental strain DNA fragments existing in GEMs-Fhhh.

    Science.gov (United States)

    Hao, Chun-Bo; Yan, Jun; Qu, Meng-Meng; Wang, Dong; Cheng, Shu-Pei; Gu, Ji-Dong; Qiu, Wan-Fei; Wang, Yin-Yin

    2003-09-01

    There were 6 target DNA fragments of the three parental strains existing in the cell of GEMs (genetically engineered microorganism strain) Fhhh measured in this research by PCR(polymerase chain reaction). The determination showed that GEMs Fhhh contained all the 6 target DNA fragments, mnp1, mnp2, lip1, lip2, FLO1 and 16S rDNA, and had the molecular genetic stability. Meanwhile the PCR production of each parental strain could only had its target DNA fragments and was different from each other. It may illustrate that the technique of the inter-kingdom protoplast fusion for the construction of GEMs Fhhh through the process of intercellular gene recombination could be used as a reliable bioengineering technique to create the specific functional stain for the pollution control.

  9. Study of gain variation as a function of physical parameters of GEM foil

    CERN Document Server

    Das, Supriya

    2015-01-01

    The ALICE experiment at LHC has planned to upgrade the TPC by replacing the MWPC with GEM based detecting elements to restrict the IBF to a tolerable value. However the variation of the gain as a function of physical parameters of industrially produced large size GEM foils is needed to be studied as a part of the QA procedure for the detector. The size of the electron avalanche and consequently the gain for GEM based detectors depend on the electric field distribution inside the holes. Geometry of a hole plays an important role in defining the electric field inside it. In this work we have studied the variation of the gain as a function of the hole diameters using Garfield++ simulation package.

  10. La Gemäldegalerie di Dresda. Evoluzione dal Settecento a fine Ottocento

    Directory of Open Access Journals (Sweden)

    Aloisia Marzotto Caotorta

    2015-12-01

    Full Text Available Since its foundation, the Gemäldegalerie (Old Masters Picture Gallery in Dresden has been considered one of the most magnificent picture galleries in Europe. Not only during the Augustan Age there was a keen interest in the arts, but also a strong understanding of the arts as a means of political power claims. In this context, the Gemäldegalerie was the most representative display of this phenomenon. This article aims to explore the complex role played by the galleries of royal and aristocratic residences in Saxony, concentrating on the Gemäldegalerie between the 18th and 19th centuries as a case study, as well as focusing on its impact on contemporary German literature.

  11. Optical characterization of synthetic faceted gem materials grown from hydrothermal solutions

    Science.gov (United States)

    Lu, Taijin; Shigley, James E.

    1998-10-01

    Various non-destructive optical characterization techniques have been used to characterize and identify synthetic gem materials grown from hydrothermal solutions, to include ruby, sapphire, emerald, amethyst and ametrine (amethyst-citrine), from their natural counterparts. The ability to observe internal features, such as inclusions, dislocations, twins, color bands, and growth zoning in gem materials is strongly dependent on the observation techniques and conditions, since faceted gemstones have many polished surfaces which can reflect and scatter light in various directions which can make observation difficult. However, diagnostic gemological properties of these faceted synthetic gem materials can be obtained by choosing effective optical characterization methods, and by modifying optical instruments. Examples of some of the distinctive features of synthetic amethyst, ametrine, pink quartz, ruby and emerald are presented to illustrate means of optical characterization of gemstones. The ability to observe defects by light scattering techniques is discussed.

  12. An aging study of triple GEMs in Ar-CO sub 2

    CERN Document Server

    Guirl, L; May, J; Miyamoto, J; Shipsey, I

    2002-01-01

    An aging study was performed using triple GEMs and a print circuit board (PCB) with an intense X-ray radiation source. The GEM chamber consists of three identical GEMs and a large gas gain (6000) was shared by them. The chamber and its gas circulation line was carefully cleaned and constructed with stainless steel materials. The detector was irradiated continuously about 750 h without interruption until a large amount of charge was accumulated. A single-wire counter served as a monitoring device to check the beam and ambient conditions. The quality of the Ar-CO sub 2 gas was checked by gas chromatography and no measurable amount of hydrocarbons were found. 27 mC/mm sup 2 was accumulated with no noticeable degradation and no deposit or discoloration was found in an optical check.

  13. Reservoir Model Information System: REMIS

    Science.gov (United States)

    Lee, Sang Yun; Lee, Kwang-Wu; Rhee, Taehyun; Neumann, Ulrich

    2009-01-01

    We describe a novel data visualization framework named Reservoir Model Information System (REMIS) for the display of complex and multi-dimensional data sets in oil reservoirs. It is aimed at facilitating visual exploration and analysis of data sets as well as user collaboration in an easier way. Our framework consists of two main modules: the data access point module and the data visualization module. For the data access point module, the Phrase-Driven Grammar System (PDGS) is adopted for helping users facilitate the visualization of data. It integrates data source applications and external visualization tools and allows users to formulate data query and visualization descriptions by selecting graphical icons in a menu or on a map with step-by-step visual guidance. For the data visualization module, we implemented our first prototype of an interactive volume viewer named REMVR to classify and to visualize geo-spatial specific data sets. By combining PDGS and REMVR, REMIS assists users better in describing visualizations and exploring data so that they can easily find desired data and explore interesting or meaningful relationships including trends and exceptions in oil reservoir model data.

  14. Advances in Trace Element “Fingerprinting” of Gem Corundum, Ruby and Sapphire, Mogok Area, Myanmar

    Directory of Open Access Journals (Sweden)

    F. Lin Sutherland

    2014-12-01

    Full Text Available Mogok gem corundum samples from twelve localities were analyzed for trace element signatures (LA-ICP-MS method and oxygen isotope values (δ18O, by laser fluorination. The study augmented earlier findings on Mogok gem suites that suggested the Mogok tract forms a high vanadium gem corundum area and also identified rare alluvial ruby and sapphire grains characterised by unusually high silicon, calcium and gallium, presence of noticeable boron, tin and niobium and very low iron, titanium and magnesium contents. Oxygen isotope values (δ18O for the ruby and high Si-Ca-Ga corundum (20‰–25‰ and for sapphire (10‰–20‰ indicate typical crustal values, with values >20‰ being typical of carbonate genesis. The high Si-Ca-Ga ruby has high chromium (up to 3.2 wt % Cr and gallium (up to 0. 08 wt % Ga compared to most Mogok ruby (<2 wt % Cr; <0.02 wt % Ga. In trace element ratio plots the Si-Ca-Ga-rich corundum falls into separate fields from the typical Mogok metamorphic fields. The high Ga/Mg ratios (46–521 lie well within the magmatic range (>6, and with other features suggest a potential skarn-like, carbonate-related genesis with a high degree of magmatic fluid input The overall trace element results widen the range of different signatures identified within Mogok gem corundum suites and indicate complex genesis. The expanded geochemical platform, related to a variety of metamorphic, metasomatic and magmatic sources, now provides a wider base for geographic typing of Mogok gem corundum suites. It allows more detailed comparisons with suites from other deposits and will assist identification of Mogok gem corundum sources used in jewelry.

  15. Gas Purity Effect on GEM Performance in He and Ne at Low Temperatures

    Science.gov (United States)

    Galea, R.; Dodd, J.; Ju, Y.; Leltchouk, M.; Willis, W.; Rehak, P.; Tcherniatine, V.; Buzulutskov, A.; Pavlyuchenko, D.

    2006-08-01

    The performance of Gas Electron Multipliers (GEMs) in gaseous He, Ne, He+H2 and Ne+H2 was studied at temperatures in the range of 3-293 K. This paper reports on previously published measurements and additional studies on the effects of the purity of the gases in which the GEM performance is evaluated. In He, at temperatures between 77 and 293 K, triple-GEM structures operate at rather high gains, exceeding 1000. There is an indication that this high gain is achieved through the Penning effect as a result of impurities in the gas. At lower temperatures the gain-voltage characteristics are significantly modified probably due to the freeze-out of these impurities. Double-GEM and single-GEM structures can operate down to 3 K at gains reaching only several tens at a gas density of about 0.5 g/l; at higher densities the maximum gain drops further. In Ne, the maximum gain also drops at cryogenic temperatures. The gain drop in Ne at low temperatures can be re-established in Penning mixtures of Ne+H2: very high gains, exceeding 104, have been obtained in these mixtures at 30-77 K, at a density of 9.2 g/l which corresponds to saturated Ne vapor density at 27 K. The addition of small amounts of H2 in He also re-establishes large GEM gains above 30 K but no gain was observed in He+H2 at 4 K and a density of 1.7 g/l (corresponding to roughly one-tenth of the saturated vapor density). These studies are, in part, being pursued in the development of two-phase He and Ne detectors for solar neutrino detection.

  16. Modeling learning technology systems as business systems

    NARCIS (Netherlands)

    Avgeriou, Paris; Retalis, Symeon; Papaspyrou, Nikolaos

    2003-01-01

    The design of Learning Technology Systems, and the Software Systems that support them, is largely conducted on an intuitive, ad hoc basis, thus resulting in inefficient systems that defectively support the learning process. There is now justifiable, increasing effort in formalizing the engineering

  17. Bond graph modeling of centrifugal compression systems

    OpenAIRE

    Uddin, Nur; Gravdahl, Jan Tommy

    2015-01-01

    A novel approach to model unsteady fluid dynamics in a compressor network by using a bond graph is presented. The model is intended in particular for compressor control system development. First, we develop a bond graph model of a single compression system. Bond graph modeling offers a different perspective to previous work by modeling the compression system based on energy flow instead of fluid dynamics. Analyzing the bond graph model explains the energy flow during compressor surge. Two pri...

  18. Structuring Problem Analysis for Embedded Systems Modelling

    NARCIS (Netherlands)

    Marincic, J.; Mader, Angelika H.; Wieringa, Roelf J.; Lucas, Yan

    Our interest is embedded systems validation as part of the model-driven approach. To design a model, the modeller needs to obtain knowledge about the system and decide what is relevant to model and how. A part of the modelling activities is inherently informal - it cannot be formalised in such a way

  19. What can we learn from the endogeneization of the technical progress in GEM - E3? The case of the Kyoto protocol

    International Nuclear Information System (INIS)

    Fougeyrollas, A.; Le Mouel, P.; Zagame, P.

    2007-01-01

    This project aims to study how the evaluation of the policies of fight against the greenhouse effect gases emission studied at an european scale, in the framework of the Kyoto agreements, is modified when the applied model, of general equilibrium takes into account the behavior of endogenous growth described by the new theories. More specially, the authors calibrated a production module with endogenous growth properties in the model GEM-E3. The new developed module show the costs reduction of policies of greenhouse effect gases emission limitation for France and Europe. (A.L.B.)

  20. The TOTEM T2 telescope based on triple-GEM chambers

    CERN Document Server

    Bagliesi, M G; Brucken, E; Cecchi, R; David, E; Garcia, F; Greco, V; Heino, J; Hilden, T; Kurvinen, K; Lauhakangas, R; Lami, S; Latino, G; Magazzu, G; Oliveri, E; Pedreschi, E; Ropelewski, L; Scribano, A; Spinella, F; Turini, N; van Stenis, M

    2010-01-01

    The TOTEM experiment at LHC has chosen the triple Gas Electron Multiplier (GEM) technology for its T2 telescope which will provide charged track reconstruction in the pseudorapidity range 5.3<|η|<6.5 and a fully inclusive trigger for inelastic events. GEMs are gas filled detectors which combine good spatial resolution with very high rate capability and a good resistance to radiation. Preliminary results of cosmic ray tests performed at CERN on final T2 modules before installation are here presented. Comparisons between real and simulated detector performance are also shown.

  1. The TOTEM T2 telescope based on triple-GEM chambers

    Energy Technology Data Exchange (ETDEWEB)

    Bagliesi, M.G., E-mail: mg.bagliesi@pi.infn.i [University of Siena and INFN Pisa (Italy); Berretti, M. [University of Siena and INFN Pisa (Italy); Brucken, E. [Helsinki (Finland); Cecchi, R. [University of Siena and INFN Pisa (Italy); David, E. [CERN, Geneva (Switzerland); Garcia, F. [Helsinki (Finland); Greco, V. [University of Siena and INFN Pisa (Italy); Heino, J.; Hilden, T.; Kurvinen, K.; Lauhakangas, R. [Helsinki (Finland); Lami, S.; Latino, G.; Magazzu, G.; Oliveri, E.; Pedreschi, E. [University of Siena and INFN Pisa (Italy); Ropelewski, L. [CERN, Geneva (Switzerland); Scribano, A.; Spinella, F.; Turini, N. [University of Siena and INFN Pisa (Italy)

    2010-05-21

    The TOTEM experiment at LHC has chosen the triple Gas Electron Multiplier (GEM) technology for its T2 telescope which will provide charged track reconstruction in the pseudorapidity range 5.3<|{eta}|<6.5 and a fully inclusive trigger for inelastic events. GEMs are gas filled detectors which combine good spatial resolution with very high rate capability and a good resistance to radiation. Preliminary results of cosmic ray tests performed at CERN on final T2 modules before installation are here presented. Comparisons between real and simulated detector performance are also shown.

  2. Financial recognition of material misstatement risks of listed companies on GEM

    Directory of Open Access Journals (Sweden)

    Jie Ming

    2017-11-01

    Full Text Available Listed companies on GEM are characterized by strong innovation, great growth ability, high risks and high yields. Starting from these characteristics, this paper carries out analysis by using the financial indicators that are effective to recognize the material misstatement risks and easy to be acquired, and combines with the sample data with high material misstatement risks on GEM in 2012 to 2014 to test the significance of spss difference, and finds that the material misstatement company and the normal company have significant difference in the profitability, solvency, growth ability and cash flow.

  3. Experimental and simulation study of the behaviour and operation modes of MSGC+GEM detectors

    Energy Technology Data Exchange (ETDEWEB)

    Ageron, M.; Albert, A.; Barvich, T.; Beaumont, W.; Beckers, T.; Bernier, K.; Bluem, P.; Boulogne, I.; Bouvet, D.; Brom, J.M.; Charles, F.; Coffin, J.; Contardo, D.; Daubie, E.; Didierjean, F.; De Lentdecker, G. E-mail: delentdecker@hep.iihe.ac.be; De Troy, J.; Devroede, O.; Erdmann, M.; Ernenwein, J.P.; Fahrer, M.; Fluegge, G.; Fontaine, J.C.; Geist, W.; Goerlach, U.; Gottschalk, M.; Helleboid, J.M.; Huss, D.; Iacopi, F.; Juillot, P.; Kaercher, K.; Kuehn, F.; Lounis, A.; Maazouzi, C.; Macke, D.; Martin, C.; Mirabito, L.; Moreau, S.; Mueller, T.; Neuberger, D.; Nowack, A.; Perries, S.; Ripp-Baudot, I.; Roederer, F.; Schulte, R.; Shekhtman, L.; Simonis, H.J.; Struczinski, W.; Tatarinov, A.; Thuemmel, W.H.; Udo, F.; Vander Velde, C.; Van Doninck, W.; Van Dyck, C.; Vanlaer, P.; Van Lancker, L.; Weiler, T.; Zander, A.; Zghiche, A.; Zhukov, V

    2002-08-21

    A small series production of detector modules made of MicroStrip Gas Counters (MSGC) and a Gas Electron Multiplier (GEM) foil has been exposed to a high-intensity hadron beam. We report about the reproductibility and stability of the detector responses and about the occurrence and consequences of discharges in the detector. The interdependence of the four voltage differences used in the detector has been studied by simulation and with X-ray measurements. Rate dependence of the signal amplitude is observed. The behaviour of the MSGC+GEM is compared to that of a state-of-the-art MSGC. Influence of various parameters on the detector response is investigated.

  4. Study of gem materials by neutron irradiation: characterization of impurities and color centers

    International Nuclear Information System (INIS)

    Leal, Alexandre S.; Menezes, Maria A.B.C.; Brito, Walter de; D'Urco, Ana F.A.; Felix, Marcia C.; Krambrock, Klaus; Ferreira, Ana F.

    2005-01-01

    Since one-century laboratory irradiation techniques are applied to the color enhancement of gem minerals. Its actual status and applications are discussed. Many different colors in a variety of gem minerals can be produced by gamma, electron and neutron irradiation combined with thermal treatments, however, many color centers and coloration processes are not known in detail. In this work we present examples of neutron irradiation applied to colorless topaz, spodumene and diamond. Topaz and diamond turned blue, spodumene orange. All color centers produced by neutron irradiation are stable to elevated temperatures and can be considered as color enhancing processes. (author)

  5. Quality assurance of GEM foils in the framework of the TPC upgrade in the ALICE experiment

    CERN Document Server

    Ozcelik, Melih Arslan

    2016-01-01

    In the framework of the TPC upgrade of the ALICE Experiment, new readout chambers will be installed during the LHC long shutdown 2, which is scheduled to start in July 2018. The current MWPCs (Multi Wire Proportional Chambers) will be replaced by readout chambers consisting of GEM (Gas Electron Multipliers) foils in order to meet the increasing readout rate requirements. QA (Quality Assurance) tests on the GEMs are performed to classify the foils. In this report we present the work done during the CERN Summer Student Programme 2016.

  6. Proceso de creación de Almus-Gemüse: pates de legumbres

    OpenAIRE

    MATA CAGIGAO, ELENA

    2016-01-01

    [ES] Almus-Gemüse es proyecto de diseño de producto enmarcado en un proyecto empresarial presentado al certamen nacional Ecotrophelia 2016. Con él los alumnos implicados consiguieron el tercer puesto. Almus-Gemüse está enfocado a la elaboración de productos con textura de paté, con altramuces como ingrediente base. El proyecto propone una gamma de productos sabores del mundo creados con diferentes especias e ingredientes. Para el desarrollo de este proyecto se emplearon las cinco pa...

  7. Construction of the TH-GEM detector components for metrology of low energy ionizing radiation

    International Nuclear Information System (INIS)

    Silva, N.F.; Castro, M.C.; Caldas, L.V.E.; Silva, T.F.; Luz, H. Natal da

    2017-01-01

    The Gas Electron Multiplier (GEM) detector was originally proposed as a position sensitive detector to determine trajectories of particles prevenient from high energy collisions. In order to study the potential of TH-GEM type detectors in dosimetric applications for low energy X-rays, specifically for the mammography standard qualities, it was proposed to construct a prototype with characteristics suitable for such use. In this work the general, structural and material parameters applicable to the necessary conditions were defined, establishing the process of construction of the components of a prototype. (author)

  8. Test beam results with prototypes for the new Cylindrical GEM Inner Tracker of the BESIII experiment arXiv

    CERN Document Server

    Lavezzi, L.; Amoroso, A.; Ferroli, R. Baldini; Bertani, M.; Bettoni, D.; Bianchi, F.; Calcaterra, A.; Canale, N.; Capodiferro, M.; Carassiti, V.; Cerioni, S.; Chai, JY.; Chiozzi, S.; Cibinetto, G.; Cossio, F.; Cotta Ramusino, A.; De Mori, F.; Destefanis, M.; Dong, J.; Evangelisti, F.; Farinelli, R.; Fava, L.; Felici, G.; Fioravanti, E.; Garzia, I.; Gatta, M.; Greco, M.; Leng, CY.; Li, H.; Maggiora, M.; Malaguti, R.; Marcello, S.; Melchiorri, M.; Mezzadri, G.; Mignone, M.; Morello, G.; Pacetti, S.; Patteri, P.; Pellegrino, J.; Pelosi, A.; Rivetti, A.; Rolo, M.D.; Savrie', M.; Scodeggio, M.; Soldani, E.; Sosio, S.; Spataro, S.; Tskhadadze, E.; Verma, S.; Wheadon, R.; Yan, L.

    A cylindrical GEM tracker is under construction in order to replace and improve the inner tracking system of the BESIII experiment. Tests with planar chamber prototypes were carried out on the H4 beam line of SPS (CERN) with muons of 150 GeV/c momentum, to evaluate the efficiency and resolution under different working conditions. The obtained efficiency was in the 96 - 98% range. Two complementary algorithms for the position determination were developed: the charge centroid and the micro-TPC methods. With the former, resolutions <100 micron and <200 micron were achieved without and with magnetic field, respectively. The micro-TPC improved these results. By the end of 2016, the first cylindrical prototype was tested on the same beam line. It showed optimal stability under different settings. The comparison of its performance with respect to the planar chambers is ongoing. Here, the results of the planar prototype tests will be addressed.

  9. Relativistic radiation belt electron responses to GEM magnetic storms: Comparison of CRRES observations with 3-D VERB simulations

    Science.gov (United States)

    Kim, Kyung-Chan; Shprits, Yuri; Subbotin, Dmitriy; Ni, Binbin

    2012-08-01

    Understanding the dynamics of relativistic electron acceleration, loss, and transport in the Earth's radiation belt during magnetic storms is a challenging task. The U.S. National Science Foundation's Geospace Environment Modeling (GEM) has identified five magnetic storms for in-depth study that occurred during the second half of the Combined Release and Radiation Effects Satellite (CRRES) mission in the year 1991. In this study, we show the responses of relativistic radiation belt electrons to the magnetic storms by comparing the time-dependent 3-D Versatile Electron Radiation Belt (VERB) simulations with the CRRES MEA 1 MeV electron observations in order to investigate the relative roles of the competing effects of previously proposed scattering mechanisms at different storm phases, as well as to examine the extent to which the simulations can reproduce observations. The major scattering processes in our model are radial transport due to Ultra Low Frequency (ULF) electromagnetic fluctuations, pitch angle and energy diffusion including mixed diffusion by whistler mode chorus waves outside the plasmasphere, and pitch angle scattering by plasmaspheric hiss inside the plasmasphere. The 3-D VERB simulations show that during the storm main phase and early recovery phase the estimated plasmapause is located deep in the inner region, indicating that pitch angle scattering by chorus waves can be a dominant loss process in the outer belt. We have also confirmed the important role played by mixed energy-pitch angle diffusion by chorus waves, which tends to reduce the fluxes enhanced by local acceleration, resulting in comparable levels of computed and measured fluxes. However, we cannot reproduce the more pronounced flux dropout near the boundary of our simulations during the main phase, which indicates that non-adiabatic losses may extend toL-shells lower than our simulation boundary. We also provide a detailed description of simulations for each of the GEM storm events.

  10. Modeling Power Systems as Complex Adaptive Systems

    Energy Technology Data Exchange (ETDEWEB)

    Chassin, David P.; Malard, Joel M.; Posse, Christian; Gangopadhyaya, Asim; Lu, Ning; Katipamula, Srinivas; Mallow, J V.

    2004-12-30

    Physical analogs have shown considerable promise for understanding the behavior of complex adaptive systems, including macroeconomics, biological systems, social networks, and electric power markets. Many of today's most challenging technical and policy questions can be reduced to a distributed economic control problem. Indeed, economically based control of large-scale systems is founded on the conjecture that the price-based regulation (e.g., auctions, markets) results in an optimal allocation of resources and emergent optimal system control. This report explores the state-of-the-art physical analogs for understanding the behavior of some econophysical systems and deriving stable and robust control strategies for using them. We review and discuss applications of some analytic methods based on a thermodynamic metaphor, according to which the interplay between system entropy and conservation laws gives rise to intuitive and governing global properties of complex systems that cannot be otherwise understood. We apply these methods to the question of how power markets can be expected to behave under a variety of conditions.

  11. Software Engineering Support of the Third Round of Scientific Grand Challenge Investigations: Earth System Modeling Software Framework Survey

    Science.gov (United States)

    Talbot, Bryan; Zhou, Shu-Jia; Higgins, Glenn; Zukor, Dorothy (Technical Monitor)

    2002-01-01

    One of the most significant challenges in large-scale climate modeling, as well as in high-performance computing in other scientific fields, is that of effectively integrating many software models from multiple contributors. A software framework facilitates the integration task, both in the development and runtime stages of the simulation. Effective software frameworks reduce the programming burden for the investigators, freeing them to focus more on the science and less on the parallel communication implementation. while maintaining high performance across numerous supercomputer and workstation architectures. This document surveys numerous software frameworks for potential use in Earth science modeling. Several frameworks are evaluated in depth, including Parallel Object-Oriented Methods and Applications (POOMA), Cactus (from (he relativistic physics community), Overture, Goddard Earth Modeling System (GEMS), the National Center for Atmospheric Research Flux Coupler, and UCLA/UCB Distributed Data Broker (DDB). Frameworks evaluated in less detail include ROOT, Parallel Application Workspace (PAWS), and Advanced Large-Scale Integrated Computational Environment (ALICE). A host of other frameworks and related tools are referenced in this context. The frameworks are evaluated individually and also compared with each other.

  12. Visual computing model for immune system and medical system.

    Science.gov (United States)

    Gong, Tao; Cao, Xinxue; Xiong, Qin

    2015-01-01

    Natural immune system is an intelligent self-organizing and adaptive system, which has a variety of immune cells with different types of immune mechanisms. The mutual cooperation between the immune cells shows the intelligence of this immune system, and modeling this immune system has an important significance in medical science and engineering. In order to build a comprehensible model of this immune system for better understanding with the visualization method than the traditional mathematic model, a visual computing model of this immune system was proposed and also used to design a medical system with the immune system, in this paper. Some visual simulations of the immune system were made to test the visual effect. The experimental results of the simulations show that the visual modeling approach can provide a more effective way for analyzing this immune system than only the traditional mathematic equations.

  13. Model Information Exchange System (MIXS).

    Science.gov (United States)

    2013-08-01

    Many travel demand forecast models operate at state, regional, and local levels. While they share the same physical network in overlapping geographic areas, they use different and uncoordinated modeling networks. This creates difficulties for models ...

  14. Two sustainable energy system analysis models

    DEFF Research Database (Denmark)

    Lund, Henrik; Goran Krajacic, Neven Duic; da Graca Carvalho, Maria

    2005-01-01

    This paper presents a comparative study of two energy system analysis models both designed with the purpose of analysing electricity systems with a substantial share of fluctuating renewable energy.......This paper presents a comparative study of two energy system analysis models both designed with the purpose of analysing electricity systems with a substantial share of fluctuating renewable energy....

  15. Models for multimegawatt space power systems

    Energy Technology Data Exchange (ETDEWEB)

    Edenburn, M.W.

    1990-06-01

    This report describes models for multimegawatt, space power systems which Sandia's Advanced Power Systems Division has constructed to help evaluate space power systems for SDI's Space Power Office. Five system models and models for associated components are presented for both open (power system waste products are exhausted into space) and closed (no waste products) systems: open, burst mode, hydrogen cooled nuclear reactor -- turboalternator system; open, hydrogen-oxygen combustion turboalternator system; closed, nuclear reactor powered Brayton cycle system; closed, liquid metal Rankine cycle system; and closed, in-core, reactor therminonic system. The models estimate performance and mass for the components in each of these systems. 17 refs., 8 figs., 15 tabs.

  16. Serial data acquisition for the X-ray plasma diagnostics with selected GEM detector structures

    International Nuclear Information System (INIS)

    Czarski, T.; Chernyshova, M.; Pozniak, K.T.; Kasprowicz, G.; Zabolotny, W.; Kolasinski, P.; Krawczyk, R.; Wojenski, A.; Zienkiewicz, P.

    2015-01-01

    The measurement system based on GEM—Gas Electron Multiplier detector is developed for X-ray diagnostics of magnetic confinement tokamak plasmas. The paper is focused on the measurement subject and describes the fundamental data processing to obtain reliable characteristics (histograms) useful for physicists. The required data processing have two steps: 1—processing in the time domain, i.e. events selections for bunches of coinciding clusters, 2—processing in the planar space domain, i.e. cluster identification for the given detector structure. So, it is the software part of the project between the electronic hardware and physics applications. The whole project is original and it was developed by the paper authors. The previous version based on 1-D GEM detector was applied for the high-resolution X-ray crystal spectrometer KX1 in the JET tokamak. The current version considers 2-D detector structures for the new data acquisition system. The fast and accurate mode of data acquisition implemented in the hardware in real time can be applied for the dynamic plasma diagnostics. Several detector structures with single-pixel sensors and multi-pixel (directional) sensors are considered for two-dimensional X-ray imaging. Final data processing is presented by histograms for selected range of position, time interval and cluster charge values. Exemplary radiation source properties are measured by the basic cumulative characteristics: the cluster position distribution and cluster charge value distribution corresponding to the energy spectra. A shorter version of this contribution is due to be published in PoS at: 1 st EPS conference on Plasma Diagnostics

  17. Serial data acquisition for the X-ray plasma diagnostics with selected GEM detector structures

    Science.gov (United States)

    Czarski, T.; Chernyshova, M.; Pozniak, K. T.; Kasprowicz, G.; Zabolotny, W.; Kolasinski, P.; Krawczyk, R.; Wojenski, A.; Zienkiewicz, P.

    2015-10-01

    The measurement system based on GEM—Gas Electron Multiplier detector is developed for X-ray diagnostics of magnetic confinement tokamak plasmas. The paper is focused on the measurement subject and describes the fundamental data processing to obtain reliable characteristics (histograms) useful for physicists. The required data processing have two steps: 1—processing in the time domain, i.e. events selections for bunches of coinciding clusters, 2—processing in the planar space domain, i.e. cluster identification for the given detector structure. So, it is the software part of the project between the electronic hardware and physics applications. The whole project is original and it was developed by the paper authors. The previous version based on 1-D GEM detector was applied for the high-resolution X-ray crystal spectrometer KX1 in the JET tokamak. The current version considers 2-D detector structures for the new data acquisition system. The fast and accurate mode of data acquisition implemented in the hardware in real time can be applied for the dynamic plasma diagnostics. Several detector structures with single-pixel sensors and multi-pixel (directional) sensors are considered for two-dimensional X-ray imaging. Final data processing is presented by histograms for selected range of position, time interval and cluster charge values. Exemplary radiation source properties are measured by the basic cumulative characteristics: the cluster position distribution and cluster charge value distribution corresponding to the energy spectra. A shorter version of this contribution is due to be published in PoS at: 1st EPS conference on Plasma Diagnostics

  18. arXiv GEM Foil Quality Assurance For The ALICE TPC Upgrade

    CERN Document Server

    INSPIRE-00019412; Hildén, Timo

    2018-01-01

    The ALICE (A Large Ion Collider Experiment) experiment at the Large Hadron Collider (LHC) at CERN is dedicated to heavy ion physics to explore the structure of strongly interacting matter. The Time Projection Chamber (TPC) of ALICE is a tracking detector located in the central region of the experiment. It offers excellent tracking capabilities as well as particle identification. After the second long shutdown (LS2) the LHC will run at substantially higher luminosities. To be able to increase the data acquisition rate by a factor of 100, the ALICE TPC experiment has to replace the Multi-Wire Proportional Chamber (MWPC) –based readout chambers. The MWPC are operated with gating grid that limits the rate to O(kHz). The new ReadOut Chamber (ROC) design is based on Gas Electron Multiplier (GEM) technology operating in continuous mode. The current GEM productions scheme foresees the production of more than 800 GEM foils of different types. To fulfill the requirements on the performance of the GEM TPC readout, nec...

  19. 16 CFR 23.25 - Misuse of the word “gem.”

    Science.gov (United States)

    2010-01-01

    ... other industry product that does not possess the beauty, symmetry, rarity, and value necessary for... JEWELRY, PRECIOUS METALS, AND PEWTER INDUSTRIES § 23.25 Misuse of the word “gem.” (a) It is unfair or... industry product unless the product meets the requirements of paragraph (a) of this section and unless such...

  20. LHCb: A fast triple-GEM detector for high-rate charged-particle triggering

    CERN Multimedia

    2001-01-01

    - GEM: Principle of Operation - Time Performances - Detector Prototypes and Test Setup - Gas Mixtures - Fields Optimisation - Vgem Optimisation Ar/CO2 (70/30) - Vgem Optimisation Ar/CO2/CF4 (60/20/20) - Time Distributions - Future Tests and Developments

  1. GEM detector performance and efficiency in Proton Charge Radius (PRad) Experiment

    Science.gov (United States)

    Bai, Xinzhan; PRad Collaboration

    2017-09-01

    The PRad experiment (E12-11-106) was performed in 2016 at Jefferson Lab in Hall B. It aims to investigate the proton charge radius puzzle through electron proton elastic scattering process. The experiment used a non-magnetic spectrometer method, and reached a very small ep scattering angle and thus an unprecedented small four-momentum transfer squared region, Q2 from 2 ×10-4 to 0.06(GeV / c) 2 . PRad experiment was designed to measure the proton charge radius within a sub-percent precision. Gas Electron Multiplier (GEM) detectors have contributed to reach the experimental goal. A pair of large area GEM detectors, and a large acceptance, high resolution calorimeter(HyCal) were utilized in the experiment to detect the scattered electrons. The precision requirements of the experiment demands a highly accurate understanding of efficiency and stability of GEM detectors. In this talk, we will present the preliminary results on the performance and efficiency of GEM detectors. This work is supported in part by NSF MRI award PHY-1229153, the U.S. Department of Energy under Contract No. DE-FG02-07ER41528, No. DE-FG02-03ER41240 and Thomas Jefferson National Laboratory.

  2. Implementation of the P barANDA Planar-GEM tracking detector in Monte Carlo simulations

    Science.gov (United States)

    Divani Veis, Nazila; Ehret, Andre; Firoozabadi, Mohammad M.; Karabowicz, Radoslaw; Maas, Frank; Saito, Nami; Saito, Takehiko R.; Voss, Bernd; PANDA Gem-Tracker Subgroup

    2018-02-01

    The P barANDA experiment at FAIR will be performed to investigate different aspects of hadron physics using anti-proton beams interacting with a fixed nuclear target. The experimental setup consists of a complex series of detector components covering a large solid angle. A detector with a gaseous active media equipped with gas electron multiplier (GEM) technique will be employed to measure tracks of charged particles at forward direction in order to achieve a high momentum resolution. In this work, a full setup of the GEM tracking detector has been implemented in the P barANDA Monte Carlo simulation package (PandaRoot) based on the current technical and conceptual design, and the expected performance of the P barANDA GEM-tracking detector has been investigated. Furthermore, material-budget studies in terms of the radiation length of the P barANDA GEM-tracking detector have been made in order to investigate the effect of the detector materials and its associated structures to particle measurements.

  3. [Occupational health status of migrant female workers of artificial gem manufacturing cottages in Guangxi].

    Science.gov (United States)

    Wang, Chao-Ying; Wang, Fang; Wang, Hui-Ming; Chen, Run-Jie; Yu, Wen-Lan

    2011-09-01

    To investigate occupational health status in migrant female workers in artificial gem cottages in Guangxi and to provide reference evidence for drawing up countermeasures to protect migrant female workers from occupational hazards. Two thousands and ninety five migrant female workers in artificial gem manufacturing cottages in Wuzhou City, Guangxi Province, were randomly recruited to participate in the investigation. The standardized occupational health questionnaires were used to collect the information of demographic characteristics, occupational exposure and medical symptoms by interviewing with persons. Artificial gem manufacturing cottages in Wuzhou were mainly composed of family-workshops. There were only simple and crude hygienic facilities. Major occupational hazards included dusts, noise, vibration, hydrofluoric acid, and light stimulation. The mean age of workers was 30. Mean exposure duration was 5 years. There was no occupational health monitoring records for these workers in the past years. Major symptoms included back pain, eye discomfort, and headache. The incidence of discomfort symptoms increased with age. Occupational health protection and monitoring in artificial gem manufacturing cottage, in Guangxi have not been performed. More effective occupational health education and administration need to implement in family-type handicraft manufacturing.

  4. Experiential Engineering through iGEM--An Undergraduate Summer Competition in Synthetic Biology

    Science.gov (United States)

    Mitchell, Rudolph; Dori, Yehudit Judy; Kuldell, Natalie H.

    2011-01-01

    Unlike students in other engineering disciplines, undergraduates in biological engineering typically have limited opportunity to develop design competencies, and even fewer chances to implement their designed projects. The international Genetically Engineered Machines (iGEM) competition is a student Synthetic Biology competition that, in 2009,…

  5. The gem collection of the Rijksmuseum van Geologie en Mineralogie of Leiden The Peridots

    NARCIS (Netherlands)

    Zwaan, P.C.

    1957-01-01

    The peridots in the gem collection of our Museum were acquired a long time ago (part of them were from the collection of King William I of the Netherlands). We should be sceptical about data on the origin of this material. Firstly we do not generally know whether the stones were bought or received

  6. MeerLICHT and BlackGEM: custom-built telescopes to detect faint optical transients

    Science.gov (United States)

    Bloemen, Steven; Groot, Paul; Woudt, Patrick; Klein Wolt, Marc; McBride, Vanessa; Nelemans, Gijs; Körding, Elmar; Pretorius, Margaretha L.; Roelfsema, Ronald; Bettonvil, Felix; Balster, Harry; Bakker, Roy; Dolron, Peter; van Elteren, Arjen; Elswijk, Eddy; Engels, Arno; Fender, Rob; Fokker, Marc; de Haan, Menno; Hagoort, Klaas; de Hoog, Jasper; ter Horst, Rik; van der Kevie, Giel; Kozłowski, Stanisław; Kragt, Jan; Lech, Grzegorz; Le Poole, Rudolf; Lesman, Dirk; Morren, Johan; Navarro, Ramon; Paalberends, Willem-Jelle; Paterson, Kerry; Pawłaszek, Rafal; Pessemier, Wim; Raskin, Gert; Rutten, Harrie; Scheers, Bart; Schuil, Menno; Sybilski, Piotr W.

    2016-07-01

    We present the MeerLICHT and BlackGEM telescopes, which are wide-field optical telescopes that are currently being built to study transient phenomena, gravitational wave counterparts and variable stars. The telescopes have 65 cm primary mirrors and a 2.7 square degree field-of-view. The MeerLICHT and BlackGEM projects have different science goals, but will use identical telescopes. The first telescope, MeerLICHT, will be commissioned at Sutherland (South Africa) in the first quarter of 2017. It will co-point with MeerKAT to collect optical data commensurate with the radio observations. After careful analysis of MeerLICHT's performance, three telescopes of the same type will be commissioned in La Silla (Chile) in 2018 to form phase I of the BlackGEM array. BlackGEM aims at detecting and characterizing optical counterparts of gravitational wave events detected by Advanced LIGO and Virgo. In this contribution we present an overview of the science goals, the design and the status of the two projects.

  7. Modeling traceability in system of systems

    NARCIS (Netherlands)

    Tekinerdogan, Bedir; Erata, Ferhat

    2017-01-01

    An important aspect in SoS is the realization of the concerns in different systems that work together. Identifying and locating these concerns is important to orchestrate the overall activities and hereby to achieve the overall goal of the SoS. Moreover, concerns in SoS are rarely stable and need

  8. Modeling of Nonlinear Systems using Genetic Algorithm

    Science.gov (United States)

    Hayashi, Kayoko; Yamamoto, Toru; Kawada, Kazuo

    In this paper, a newly modeling system by using Genetic Algorithm (GA) is proposed. The GA is an evolutionary computational method that simulates the mechanisms of heredity or evolution of living things, and it is utilized in optimization and in searching for optimized solutions. Most process systems have nonlinearities, so it is necessary to anticipate exactly such systems. However, it is difficult to make a suitable model for nonlinear systems, because most nonlinear systems have a complex structure. Therefore the newly proposed method of modeling for nonlinear systems uses GA. Then, according to the newly proposed scheme, the optimal structure and parameters of the nonlinear model are automatically generated.

  9. The GTPase Gem and its partner Kif9 are required for chromosome alignment, spindle length control, and mitotic progression.

    Science.gov (United States)

    Andrieu, Guillaume; Quaranta, Muriel; Leprince, Corinne; Hatzoglou, Anastassia

    2012-12-01

    Within the Ras superfamily, Gem is a small GTP-binding protein that plays a role in regulating Ca(2+) channels and cytoskeletal remodeling in interphase cells. Here, we report for the first time that Gem is a spindle-associated protein and is required for proper mitotic progression. Functionally, loss of Gem leads to misaligned chromosomes and prometaphase delay. On the basis of different experimental approaches, we demonstrate that loss of Gem by RNA interference induces spindle elongation, while its enforced expression results in spindle shortening. The spindle length phenotype is generated through deregulation of spindle dynamics on Gem depletion and requires the expression of its downstream effector, the kinesin Kif9. Loss of Kif9 induces spindle abnormalities similar to those observed when Gem expression is repressed by siRNA. We further identify Kif9 as a new regulator of spindle dynamics. Kif9 depletion increases the steady-state levels of spindle α-tubulin by increasing the rate of microtubule polymerization. Overall, this study demonstrates a novel mechanism by which Gem contributes to the mitotic progression by maintaining correct spindle length through the kinesin Kif9.

  10. Model Driven Development of Data Sensitive Systems

    DEFF Research Database (Denmark)

    Olsen, Petur

    2014-01-01

    to the values of variables. This theses strives to improve model-driven development of such data-sensitive systems. This is done by addressing three research questions. In the first we combine state-based modeling and abstract interpretation, in order to ease modeling of data-sensitive systems, while allowing...... efficient model-checking and model-based testing. In the second we develop automatic abstraction learning used together with model learning, in order to allow fully automatic learning of data-sensitive systems to allow learning of larger systems. In the third we develop an approach for modeling and model-based...... detection and pushing error detection to earlier stages of development. The complexity of modeling and the size of systems which can be analyzed is severely limited when introducing data variables. The state space grows exponentially in the number of variable and the domain size of the variables...

  11. Modeling of a Hydraulic Braking System

    OpenAIRE

    Lundin, Christopher

    2015-01-01

    The objective of this thesis is to derive an analytical model representing a reduced form of a mine hoist hydraulic braking system. Based primarily on fluid mechanical and mechanical physical modeling, along with a number of simplifying assumptions, the analytical model will be derived and expressed in the form of a system of differential equations including a set of static functions. The obtained model will be suitable for basic simulation and analysis of system dynamics, with the aim to cap...

  12. Commercial and Cost Effective Production of Gas Electron Multiplier (GEM) Foils

    Energy Technology Data Exchange (ETDEWEB)

    Woody, Craig

    2009-03-31

    The nuclear and high energy physics research community is constantly searching for new and improved tracking and radiation detectors. The introduction of micropattern detectors has opened new opportunities for improving the rate capabilities, as well as the spatial and time resolution of particle detectors in these applications. GEM detectors in particular have received enormous interest for use in detectors planned for a number of new and upgraded experiments at many different research facilities. These include both the STAR and PHENIX experiments at the Relativistic Heavy Ion Collider at Brookhaven National Laboratory, experiments at the Thomas Jefferson National Laboratory, Oak Ridge National Laboratory, and at the future electron-positron Linear Collider. At the present time, CERN is not able to supply foils in sufficient quantities to accommodate the needs of these experiments. Compounding this problem, there is a strong interest in GEM foils for numerous other applications, such as in astrophysics, medical imaging and detectors for homeland security. It would therefore be of significant benefit to the research community to develop a commercial source of GEM foils for all of these applications. Tech-Etch is in a unique position to develop this technology for commercial use. Tech-Etch has not only experience in numerous related high precision etched Kapton® products, but it also has strong ties with several research institutions (namely Brookhaven, Yale and MIT) that can help develop and evaluate the performance of the GEM foils produced at Tech-Etch. Additionally, since Tech-Etch is a small company, it also has the capability to produce a large variety of part configurations, as well as the flexibility to shift production methods, equipment, and chemistry to optimize the GEM foil manufacturing process without being constrained by existing work running on high volume continuous coil equipment.

  13. Graphical Model Debugger Framework for Embedded Systems

    DEFF Research Database (Denmark)

    Zeng, Kebin

    2010-01-01

    Model Driven Software Development has offered a faster way to design and implement embedded real-time software by moving the design to a model level, and by transforming models to code. However, the testing of embedded systems has remained at the code level. This paper presents a Graphical Model...... Debugger Framework, providing an auxiliary avenue of analysis of system models at runtime by executing generated code and updating models synchronously, which allows embedded developers to focus on the model level. With the model debugger, embedded developers can graphically test their design model...... and check the running status of the system, which offers a debugging capability on a higher level of abstraction. The framework intends to contribute a tool to the Eclipse society, especially suitable for model-driven development of embedded systems....

  14. Chromium speciation in oxide-type compounds: application to minerals, gems, aqueous solutions and silicate glasses

    Science.gov (United States)

    Farges, François

    2009-09-01

    Cr K-edge XANES spectra were obtained for a variety of Cr-bearing model compounds containing Cr(II), Cr(III), Cr(IV), Cr(V) and Cr(VI), in which the Cr-site symmetry is D4h, Oh and Td. The centroid position of the pre-edge feature is a better indicator of the Cr valence than the edge position. In Cr-rich oxides, higher-energy transitions must be excluded in order to refine a robust valence for Cr. The pre-edge for chromates is not unique and varies as a function of the CrO4 2- moiety distortion, which is often related to Cr-polymerization (monochromate vs. dichromate). Both the analogy with the Mn K-pre-edge information and ab initio FEFF calculations of the pre-edge feature for Cr(III) and Cr(VI) confirm the experimental trends. This methodology is applied to the Cr K-edge pre-edge feature collected in gems (emerald, spinel and ruby), the layered minerals fuchsite and kämmererite, two Cr-bearing aqueous solutions and a set of sodo-calcic silicate glasses used for bottling sparkling white wine. In emerald and fuchsite, the Cr-site is differently distorted than its ruby or spinel counterpart. In a Cr(III)-bearing aqueous solution and sodo-calcic glass, no evidence for Cr(III) with Td and C3v symmetry is detected. However, minor amounts of chromate moieties (most likely monomeric) are detected in a glass synthesized in air. Preliminary spectra for the wine bottle glass suggest that only trace amounts of chromates might possibly be present in these glasses.

  15. Hydrological modelling in forested systems

    Science.gov (United States)

    This chapter provides a brief overview of forest hydrology modelling approaches for answering important global research and management questions. Many hundreds of hydrological models have been applied globally across multiple decades to represent and predict forest hydrological p...

  16. Towards Modelling of Hybrid Systems

    DEFF Research Database (Denmark)

    Wisniewski, Rafal

    2006-01-01

    The article is an attempt to use methods of category theory and topology for analysis of hybrid systems. We use the notion of a directed topological space; it is a topological space together with a set of privileged paths. Dynamical systems are examples of directed topological spaces. A hybrid...... system consists of a number of dynamical systems that are glued together according to information encoded in the discrete part of the system. We develop a definition of a hybrid system as a functor from the category generated by a transition system to the category of directed topological spaces. Its...... directed homotopy colimit (geometric realization) is a single directed topological space. The behavior of hybrid systems can be then understood in terms of the behavior of dynamical systems through the directed homotopy colimit....

  17. Results and performances of X-ray imaging GEM cameras on FTU (1-D), KSTAR (2-D) and progresses of future experimental set up on W7-X and EAST Facilities

    Science.gov (United States)

    Cordella, F.; Choe, W.; Claps, G.; Gabellieri, L.; Jang, J.; Jeon, T.; Lee, S. H.; Li, E.; Pacella, D.; Romano, A.; Song, I.

    2017-10-01

    The triple Gas Electron Multiplier (GEM) is a good candidate for the observation of the plasma volume emitting X-rays photons in the energy band up to 30 keV . The GEM camera system can be simply installed outside the port of a fusion device and it's a micropattern proportional gas detector which consists of an ionization gap, where X-rays photon conversion occurs, three consecutive foils working as amplification stage and finally a dedicated printed circuit board. Its simple experimental setup can be made in different configurations with 1D or 2D imaging possibilities: perpendicular GEM camera allows a 1D emissivity profile reconstruction instead a tangential GEM camera allows a poloidal cross-section image. Moreover, they offer high sensitivity, noise free, optical flexibility (zooming and tilting, magnification 10× up to 30×), high contrast, high dynamic range (6 orders of magnitude) and good time resolution (submillisecond). In this work several experimental results already observed on the Frascati Tokamak Upgrade (FTU) and the Korean Superconducting Tokamak Advanced Research (KSTAR) devices will be presented. The perpendicular installation on FTU allows a 1D radial profile with 128 lines of sight, while thanks to the 2D tangential view of the plasma, the reconstruction of the cross section has been done on KSTAR. Between them there are dynamic and precursors of sawtooth, effects of Edge Localized Mode (ELM) in the core and possible interplay between core and edge in ELMs (high m modes), effects of plasma rotation in the core, dynamic of injected impurities in the outer part of the plasma or also impurity accumulation and localized effects of additional heating. Installation of GEM systems is planned on Wendelstein 7-X (W7-X) and the Experimental Advanced Superconducting Tokamak (EAST) also for their robustness and flexibility X-rays detection in presence of high radiative environments (neutrons and gammas). In future applications on the above mentioned

  18. Service systems concepts, modeling, and programming

    CERN Document Server

    Cardoso, Jorge; Poels, Geert

    2014-01-01

    This SpringerBrief explores the internal workings of service systems. The authors propose a lightweight semantic model for an effective representation to capture the essence of service systems. Key topics include modeling frameworks, service descriptions and linked data, creating service instances, tool support, and applications in enterprises.Previous books on service system modeling and various streams of scientific developments used an external perspective to describe how systems can be integrated. This brief introduces the concept of white-box service system modeling as an approach to mo

  19. On Verification Modelling of Embedded Systems

    NARCIS (Netherlands)

    Brinksma, Hendrik; Mader, Angelika H.

    Computer-aided verification of embedded systems hinges on the availability of good verification models of the systems at hand. Such models must be much simpler than full design models or specifications to be of practical value, because of the unavoidable combinatorial complexities in the

  20. Balmorel open source energy system model

    DEFF Research Database (Denmark)

    Wiese, Frauke; Bramstoft, Rasmus; Koduvere, Hardi

    2018-01-01

    As the world progresses towards a cleaner energy future with more variable renewable energy sources, energy system models are required to deal with new challenges. This article describes design, development and applications of the open source energy system model Balmorel, which is a result of a l...... transport of local biomass as part of the optimisation and speeding up the model....

  1. Modeling, Control and Coordination of Helicopter Systems

    CERN Document Server

    Ren, Beibei; Chen, Chang; Fua, Cheng-Heng; Lee, Tong Heng

    2012-01-01

    Modeling, Control and Coordination of Helicopter Systems provides a comprehensive treatment of helicopter systems, ranging from related nonlinear flight dynamic modeling and stability analysis to advanced control design for single helicopter systems, and also covers issues related to the coordination and formation control of multiple helicopter systems to achieve high performance tasks. Ensuring stability in helicopter flight is a challenging problem for nonlinear control design and development. This book is a valuable reference on modeling, control and coordination of helicopter systems,providing readers with practical solutions for the problems that still plague helicopter system design and implementation. Readers will gain a complete picture of helicopters at the systems level, as well as a better understanding of the technical intricacies involved. This book also: Presents a complete picture of modeling, control and coordination for helicopter systems Provides a modeling platform for a general class of ro...

  2. Systems Biology—Biomedical Modeling

    OpenAIRE

    Sobie, Eric A.; Lee, Young-Seon; Jenkins, Sherry L.; Iyengar, Ravi

    2011-01-01

    Because of the complexity inherent in biological systems, many researchers frequently rely on a combination of global analysis and computational approaches to gain insight into both (i) how interacting components can produce complex system behaviors, and (ii) how changes in conditions may alter these behaviors. Because the biological details of a particular system are generally not taught along with the quantitative approaches that enable hypothesis generation and analysis of the system, we d...

  3. Modeling and simulation of systems using Matlab and Simulink

    CERN Document Server

    Chaturvedi, Devendra K

    2009-01-01

    Introduction to SystemsSystemClassification of SystemsLinear SystemsTime-Varying vs. Time-Invariant Systems Lumped vs. Distributed Parameter SystemsContinuous- and Discrete-Time Systems Deterministic vs. Stochastic Systems Hard and Soft Systems Analysis of Systems Synthesis of Systems Introduction to System Philosophy System Thinking Large and Complex Applied System Engineering: A Generic ModelingSystems ModelingIntroduction Need of System Modeling Modeling Methods for Complex Systems Classification of ModelsCharacteristics of Models ModelingMathematical Modeling of Physical SystemsFormulation of State Space Model of SystemsPhysical Systems Theory System Components and Interconnections Computation of Parameters of a Component Single Port and Multiport Systems Techniques of System Analysis Basics of Linear Graph Theoretic ApproachFormulation of System Model for Conceptual SystemFormulation System Model for Physical SystemsTopological RestrictionsDevelopment of State Model of Degenerative SystemSolution of Stat...

  4. Modelling and Verification of Relay Interlocking Systems

    DEFF Research Database (Denmark)

    Haxthausen, Anne Elisabeth; Bliguet, Marie Le; Kjær, Andreas

    2010-01-01

    This paper describes how relay interlocking systems as used by the Danish railways can be formally modelled and verified. Such systems are documented by circuit diagrams describing their static layout. It is explained how to derive a state transition system model for the dynamic behaviour of a re...

  5. Compositional Modelling of Stochastic Hybrid Systems

    NARCIS (Netherlands)

    Strubbe, S.N.

    2005-01-01

    In this thesis we present a modelling framework for compositional modelling of stochastic hybrid systems. Hybrid systems consist of a combination of continuous and discrete dynamics. The state space of a hybrid system is hybrid in the sense that it consists of a continuous component and a discrete

  6. Models of complex attitude systems

    DEFF Research Database (Denmark)

    Sørensen, Bjarne Taulo

    Existing research on public attitudes towards agricultural production systems is largely descriptive, abstracting from the processes through which members of the general public generate their evaluations of such systems. The present paper adopts a systems perspective on such evaluations, understa......Existing research on public attitudes towards agricultural production systems is largely descriptive, abstracting from the processes through which members of the general public generate their evaluations of such systems. The present paper adopts a systems perspective on such evaluations......, understanding them as embedded into a wider attitude system that consists of attitudes towards objects of different abstraction levels, ranging from personal value orientations over general socio-political attitudes to evaluations of specific characteristics of agricultural production systems. It is assumed...... that evaluative affect propagates through the system in such a way that the system becomes evaluatively consistent and operates as a schema for the generation of evaluative judgments. In the empirical part of the paper, the causal structure of an attitude system from which people derive their evaluations of pork...

  7. What can we learn from the endogeneization of the technical progress in GEM - E3? The case of the Kyoto protocol; Que pouvons nous apprendre de l'endogeneisation du progres technique dans GEM - E3? le cas du protocole de Kyoto

    Energy Technology Data Exchange (ETDEWEB)

    Fougeyrollas, A.; Le Mouel, P.; Zagame, P

    2007-07-01

    This project aims to study how the evaluation of the policies of fight against the greenhouse effect gases emission studied at an european scale, in the framework of the Kyoto agreements, is modified when the applied model, of general equilibrium takes into account the behavior of endogenous growth described by the new theories. More specially, the authors calibrated a production module with endogenous growth properties in the model GEM-E3. The new developed module show the costs reduction of policies of greenhouse effect gases emission limitation for France and Europe. (A.L.B.)

  8. Modeling Control Situations in Power System Operations

    DEFF Research Database (Denmark)

    Saleem, Arshad; Lind, Morten; Singh, Sri Niwas

    2010-01-01

    Increased interconnection and loading of the power system along with deregulation has brought new challenges for electric power system operation, control and automation. Traditional power system models used in intelligent operation and control are highly dependent on the task purpose. Thus, a model...... of explicit principles for model construction. This paper presents a work on using explicit means-ends model based reasoning about complex control situations which results in maintaining consistent perspectives and selecting appropriate control action for goal driven agents. An example of power system...... for intelligent operation and control must represent system features, so that information from measurements can be related to possible system states and to control actions. These general modeling requirements are well understood, but it is, in general, difficult to translate them into a model because of the lack...

  9. Holonic Models for Traffic Control Systems

    Science.gov (United States)

    Ciufudean, Calin; Filote, Constantin

    This paper proposes a new time-placed net model for traffic control systems, respectively railway control traffic systems. This model can be interpreted as a holonic one, and contains three modules: Transport Planning Module, Transport Control Module and Priority Control Module. For railway traffic systems we introduce a strategy in a timed-place Petri net model to solve collision and traffic jam problems.

  10. Hydrological modeling in forested systems

    Science.gov (United States)

    H.E. Golden; G.R. Evenson; S. Tian; Devendra Amatya; Ge Sun

    2015-01-01

    Characterizing and quantifying interactions among components of the forest hydrological cycle is complex and usually requires a combination of field monitoring and modelling approaches (Weiler and McDonnell, 2004; National Research Council, 2008). Models are important tools for testing hypotheses, understanding hydrological processes and synthesizing experimental data...

  11. Life-Cycle Models for Survivable Systems

    National Research Council Canada - National Science Library

    Linger, Richard

    2002-01-01

    .... Current software development life-cycle models are not focused on creating survivable systems, and exhibit shortcomings when the goal is to develop systems with a high degree of assurance of survivability...

  12. Model Updating Nonlinear System Identification Toolbox Project

    Data.gov (United States)

    National Aeronautics and Space Administration — ZONA Technology (ZONA) proposes to develop an enhanced model updating nonlinear system identification (MUNSID) methodology that utilizes flight data with...

  13. An expert system for dispersion model interpretation

    International Nuclear Information System (INIS)

    Skyllingstad, E.D.; Ramsdell, J.V.

    1988-10-01

    A prototype expert system designed to diagnose dispersion model uncertainty is described in this paper with application to a puff transport model. The system obtains qualitative information from the model user and through an expert-derived knowledge base, performs a rating of the current simulation. These results can then be used in combination with dispersion model output for deciding appropriate evacuation measures. Ultimately, the goal of this work is to develop an expert system that may be operated accurately by an individual uneducated in meteorology or dispersion modeling. 5 refs., 3 figs

  14. Semantic models for adaptive interactive systems

    CERN Document Server

    Hussein, Tim; Lukosch, Stephan; Ziegler, Jürgen; Calvary, Gaëlle

    2013-01-01

    Providing insights into methodologies for designing adaptive systems based on semantic data, and introducing semantic models that can be used for building interactive systems, this book showcases many of the applications made possible by the use of semantic models.Ontologies may enhance the functional coverage of an interactive system as well as its visualization and interaction capabilities in various ways. Semantic models can also contribute to bridging gaps; for example, between user models, context-aware interfaces, and model-driven UI generation. There is considerable potential for using

  15. Models of the venous system

    DEFF Research Database (Denmark)

    Mehlsen, J

    2000-01-01

    of the venous system require at least three elements: a resistor, a capacitor and an inductor, with the latter being of more importance in the venous than in the arterial system. Non-linearities must be considered in pressure/flow relations in the small venules, during venous collapse, or low flow conditions...

  16. Stochastic Models of Polymer Systems

    Science.gov (United States)

    2016-01-01

    published in non-peer-reviewed journals (N/A for none) The dynamics of stochastic gradient algorithms (submitted); Noisy Hegselmann- Krause Systems...algorithms for big data applications. (2) We studied stochastic dynamics of polymer systems in the mean field limit. (3) We studied noisy Hegselmann- Krause

  17. Switching model photovoltaic pumping system

    Science.gov (United States)

    Anis, Wagdy R.; Abdul-Sadek Nour, M.

    Photovoltaic (PV) pumping systems are widely used due to their simplicity, high reliability and low cost. A directly-coupled PV pumping system is the most reliable and least-cost PV system. The d.c. motor-pump group is not, however, working at its optimum operating point. A battery buffered PV pumping system introduces a battery between the PV array and the d.c. motor-pump group to ensure that the motor-pump group is operating at its optimum point. The size of the battery storage depends on system economics. If the battery is fully charged while solar radiation is available, the battery will discharge through the load while the PV array is disconnected. Hence, a power loss takes place. To overcome the above mentioned difficulty, a switched mode PV pumping is proposed. When solar radiation is available and the battery is fully charged, the battery is disconnected and the d.c. motor-pump group is directly coupled to the PV array. To avoid excessive operating voltage for the motor, a part of the PV array is switched off to reduce the voltage. As a result, the energy loss is significantly eliminated. Detailed analysis of the proposed system shows that the discharged water increases by about 10% when compared with a conventional battery-buffered system. The system transient performance just after the switching moment shows that the system returns to a steady state in short period. The variations in the system parameters lie within 1% of the rated values.

  18. Long-term relativistic radiation belt electron responses to GEM magnetic storms

    Science.gov (United States)

    Kim, Kyung-Chan; Shprits, Yuri

    2013-08-01

    We present a long-term radiation belt simulation for a 200-day period starting on 25 January 1991, which includes both six geomagnetic storms identified by the Geospace Environment Modeling (GEM) focus group and non-stormy periods of the Combined Release and Radiation Effects Satellite (CRRES) mission, using 3-D time-dependent Versatile Electron Radiation Belt (VERB) code, and compare the simulation results with a multisatellite phase space density (PSD) reanalysis obtained using Kalman filtering of observations from CRRES, GEO, GPS, and Akebono satellites, as well as with the CRRES MEA 1 MeV electron observation. The processes accounted for in the model are radial diffusion-driven by ultra-low frequency (ULF) electromagnetic fluctuations and local (pitch-angle and energy) scattering by plasmaspheric hiss and chorus waves, respectively, inside and outside the plasmasphere. The observations show that a significant decrease in the relativistic electrons in the outer radiation belt is observed in association with the solar wind dynamic pressure enhancement during the main phase of each storm, while during the recovery phase, different types of relativistic electron flux profiles are identified: increased, decreased, and unchanged relative to the pre-storm flux level. First, for an increase of relativistic electrons relative to the pre-storm flux level, the comparison of simulation with reanalysis shows that inward radial diffusion and local acceleration coupled with each other result in a net acceleration. Second, for a decrease or lack of change in relativistic electrons, competing effects of pitch-angle scattering, outward diffusion, and acceleration produce the net decrease in electron PSD and fluxes. The results show that the overall time evolution of the radiation belt is in good agreement with our model simulations, indicating that modeling, including radial diffusion and pitch-angle scattering, is reasonable in predicting the general long-term structure of the

  19. Multiple system modelling of waste management

    International Nuclear Information System (INIS)

    Eriksson, Ola; Bisaillon, Mattias

    2011-01-01

    Highlights: → Linking of models will provide a more complete, correct and credible picture of the systems. → The linking procedure is easy to perform and also leads to activation of project partners. → The simulation procedure is a bit more complicated and calls for the ability to run both models. - Abstract: Due to increased environmental awareness, planning and performance of waste management has become more and more complex. Therefore waste management has early been subject to different types of modelling. Another field with long experience of modelling and systems perspective is energy systems. The two modelling traditions have developed side by side, but so far there are very few attempts to combine them. Waste management systems can be linked together with energy systems through incineration plants. The models for waste management can be modelled on a quite detailed level whereas surrounding systems are modelled in a more simplistic way. This is a problem, as previous studies have shown that assumptions on the surrounding system often tend to be important for the conclusions. In this paper it is shown how two models, one for the district heating system (MARTES) and another one for the waste management system (ORWARE), can be linked together. The strengths and weaknesses with model linking are discussed when compared to simplistic assumptions on effects in the energy and waste management systems. It is concluded that the linking of models will provide a more complete, correct and credible picture of the consequences of different simultaneous changes in the systems. The linking procedure is easy to perform and also leads to activation of project partners. However, the simulation procedure is a bit more complicated and calls for the ability to run both models.

  20. Modeling of power electronic systems with EMTP

    Science.gov (United States)

    Tam, Kwa-Sur; Dravid, Narayan V.

    1989-01-01

    In view of the potential impact of power electronics on power systems, there is need for a computer modeling/analysis tool to perform simulation studies on power systems with power electronic components as well as to educate engineering students about such systems. The modeling of the major power electronic components of the NASA Space Station Freedom Electric Power System is described along with ElectroMagnetic Transients Program (EMTP) and it is demonstrated that EMTP can serve as a very useful tool for teaching, design, analysis, and research in the area of power systems with power electronic components. EMTP modeling of power electronic circuits is described and simulation results are presented.

  1. System Level Modelling and Performance Estimation of Embedded Systems

    DEFF Research Database (Denmark)

    Tranberg-Hansen, Anders Sejer

    The advances seen in the semiconductor industry within the last decade have brought the possibility of integrating evermore functionality onto a single chip forming functionally highly advanced embedded systems. These integration possibilities also imply that as the design complexity increases, so...... an efficient system level design methodology, a modelling framework for performance estimation and design space exploration at the system level is required. This thesis presents a novel component based modelling framework for system level modelling and performance estimation of embedded systems. The framework...... is performed by having the framework produce detailed quantitative information about the system model under investigation. The project is part of the national Danish research project, Danish Network of Embedded Systems (DaNES), which is funded by the Danish National Advanced Technology Foundation. The project...

  2. Network model of security system

    Directory of Open Access Journals (Sweden)

    Adamczyk Piotr

    2016-01-01

    Full Text Available The article presents the concept of building a network security model and its application in the process of risk analysis. It indicates the possibility of a new definition of the role of the network models in the safety analysis. Special attention was paid to the development of the use of an algorithm describing the process of identifying the assets, vulnerability and threats in a given context. The aim of the article is to present how this algorithm reduced the complexity of the problem by eliminating from the base model these components that have no links with others component and as a result and it was possible to build a real network model corresponding to reality.

  3. Modeling Adaptive Behavior for Systems Design

    DEFF Research Database (Denmark)

    Rasmussen, Jens

    1994-01-01

    Field studies in modern work systems and analysis of recent major accidents have pointed to a need for better models of the adaptive behavior of individuals and organizations operating in a dynamic and highly competitive environment. The paper presents a discussion of some key characteristics...... of the predictive models required for the design of work supports systems, that is,information systems serving as the human-work interface. Three basic issues are in focus: 1.) Some fundamental problems in analysis and modeling modern dynamic work systems caused by the adaptive nature of human behavior; 2.......) The basic difference between the models of system functions used in engineering and design and those evolving from basic research within the various academic disciplines and finally 3.) The models and methods required for closed-loop, feedback system design....

  4. Model-based version management system framework

    International Nuclear Information System (INIS)

    Mehmood, W.

    2016-01-01

    In this paper we present a model-based version management system. Version Management System (VMS) a branch of software configuration management (SCM) aims to provide a controlling mechanism for evolution of software artifacts created during software development process. Controlling the evolution requires many activities to perform, such as, construction and creation of versions, identification of differences between versions, conflict detection and merging. Traditional VMS systems are file-based and consider software systems as a set of text files. File based VMS systems are not adequate for performing software configuration management activities such as, version control on software artifacts produced in earlier phases of the software life cycle. New challenges of model differencing, merge, and evolution control arise while using models as central artifact. The goal of this work is to present a generic framework model-based VMS which can be used to overcome the problem of tradition file-based VMS systems and provide model versioning services. (author)

  5. Very Large System Dynamics Models - Lessons Learned

    Energy Technology Data Exchange (ETDEWEB)

    Jacob J. Jacobson; Leonard Malczynski

    2008-10-01

    This paper provides lessons learned from developing several large system dynamics (SD) models. System dynamics modeling practice emphasize the need to keep models small so that they are manageable and understandable. This practice is generally reasonable and prudent; however, there are times that large SD models are necessary. This paper outlines two large SD projects that were done at two Department of Energy National Laboratories, the Idaho National Laboratory and Sandia National Laboratories. This paper summarizes the models and then discusses some of the valuable lessons learned during these two modeling efforts.

  6. Multiscale modeling of multi-decadal trends in air pollutant concentrations and their radiative properties: the role of models in an integrated observing system

    Science.gov (United States)

    Mathur, R.; Xing, J.; Szykman, J.; Gan, C. M.; Hogrefe, C.; Pleim, J. E.

    2015-12-01

    Air Pollution simulation models must address the increasing complexity arising from new model applications that treat multi-pollutant interactions across varying space and time scales. Setting and attaining lower ambient air quality standards requires an improved understanding and quantification of source attribution amongst the multiple anthropogenic and natural sources, on time scales ranging from episodic to annual and spatial scales ranging from urban to continental. Changing emission patterns over the developing regions of the world are likely to exacerbate the impacts of long-range pollutant transport on background pollutant levels, which may then impact the attainment of local air quality standards. Thus, strategies for reduction of pollution levels of surface air over a region are complicated not only by the interplay of local emissions sources and several complex physical, chemical, dynamical processes in the atmosphere, but also hemispheric background levels of pollutants. Additionally, as short-lived climate forcers, aerosols and ozone exert regionally heterogeneous radiative forcing and influence regional climate trends. EPA's coupled WRF-CMAQ modeling system is applied over a domain encompassing the northern hemisphere for the period spanning 1990-2010. This period has witnessed significant reductions in anthropogenic emissions in North America and Europe as a result of implementation of control measures and dramatic increases across Asia associated with economic and population growth, resulting in contrasting trends in air pollutant distributions and transport patterns across the northern hemisphere. Model results (trends in pollutant concentrations, optical and radiative characteristics) across the northern hemisphere are analyzed in conjunction with surface, aloft and remote sensing measurements to contrast the differing trends in air pollution and aerosol-radiation interactions in these regions over the past two decades. Given the future LEO (Trop

  7. Test-driven modeling of embedded systems

    DEFF Research Database (Denmark)

    Munck, Allan; Madsen, Jan

    2015-01-01

    To benefit maximally from model-based systems engineering (MBSE) trustworthy high quality models are required. From the software disciplines it is known that test-driven development (TDD) can significantly increase the quality of the products. Using a test-driven approach with MBSE may have...... a similar positive effect on the quality of the system models and the resulting products and may therefore be desirable. To define a test-driven model-based systems engineering (TD-MBSE) approach, we must define this approach for numerous sub disciplines such as modeling of requirements, use cases......, scenarios, behavior, architecture, etc. In this paper we present a method that utilizes the formalism of timed automatons with formal and statistical model checking techniques to apply TD-MBSE to the modeling of system architecture and behavior. The results obtained from applying it to an industrial case...

  8. Precipitation-runoff modeling system; user's manual

    Science.gov (United States)

    Leavesley, G.H.; Lichty, R.W.; Troutman, B.M.; Saindon, L.G.

    1983-01-01

    The concepts, structure, theoretical development, and data requirements of the precipitation-runoff modeling system (PRMS) are described. The precipitation-runoff modeling system is a modular-design, deterministic, distributed-parameter modeling system developed to evaluate the impacts of various combinations of precipitation, climate, and land use on streamflow, sediment yields, and general basin hydrology. Basin response to normal and extreme rainfall and snowmelt can be simulated to evaluate changes in water balance relationships, flow regimes, flood peaks and volumes, soil-water relationships, sediment yields, and groundwater recharge. Parameter-optimization and sensitivity analysis capabilites are provided to fit selected model parameters and evaluate their individual and joint effects on model output. The modular design provides a flexible framework for continued model system enhancement and hydrologic modeling research and development. (Author 's abstract)

  9. An Empirical Model for Energy Storage Systems

    Energy Technology Data Exchange (ETDEWEB)

    Rosewater, David Martin [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Scott, Paul [TransPower, Poway, CA (United States)

    2016-03-17

    Improved models of energy storage systems are needed to enable the electric grid’s adaptation to increasing penetration of renewables. This paper develops a generic empirical model of energy storage system performance agnostic of type, chemistry, design or scale. Parameters for this model are calculated using test procedures adapted from the US DOE Protocol for Uniformly Measuring and Expressing the Performance of Energy Storage. We then assess the accuracy of this model for predicting the performance of the TransPower GridSaver – a 1 MW rated lithium-ion battery system that underwent laboratory experimentation and analysis. The developed model predicts a range of energy storage system performance based on the uncertainty of estimated model parameters. Finally, this model can be used to better understand the integration and coordination of energy storage on the electric grid.

  10. No prognostic value added by vitamin D pathway SNPs to current prognostic system for melanoma survival.

    Directory of Open Access Journals (Sweden)

    Li Luo

    Full Text Available The prognostic improvement attributed to genetic markers over current prognostic system has not been well studied for melanoma. The goal of this study is to evaluate the added prognostic value of Vitamin D Pathway (VitD SNPs to currently known clinical and demographic factors such as age, sex, Breslow thickness, mitosis and ulceration (CDF. We utilized two large independent well-characterized melanoma studies: the Genes, Environment, and Melanoma (GEM and MD Anderson studies, and performed variable selection of VitD pathway SNPs and CDF using Random Survival Forest (RSF method in addition to Cox proportional hazards models. The Harrell's C-index was used to compare the performance of model predictability. The population-based GEM study enrolled 3,578 incident cases of cutaneous melanoma (CM, and the hospital-based MD Anderson study consisted of 1,804 CM patients. Including both VitD SNPs and CDF yielded C-index of 0.85, which provided slight but not significant improvement by CDF alone (C-index = 0.83 in the GEM study. Similar results were observed in the independent MD Anderson study (C-index = 0.84 and 0.83, respectively. The Cox model identified no significant associations after adjusting for multiplicity. Our results do not support clinically significant prognostic improvements attributable to VitD pathway SNPs over current prognostic system for melanoma survival.

  11. Brief History of Agricultural Systems Modeling

    Science.gov (United States)

    Jones, James W.; Antle, John M.; Basso, Bruno O.; Boote, Kenneth J.; Conant, Richard T.; Foster, Ian; Godfray, H. Charles J.; Herrrero, Mario; Howitt, Richard E.; Janssen, Sandor; hide

    2016-01-01

    Agricultural systems science generates knowledge that allows researchers to consider complex problems or take informed agricultural decisions. The rich history of this science exemplifies the diversity of systems and scales over which they operate and have been studied. Modeling, an essential tool in agricultural systems science, has been accomplished by scientists from a wide range of disciplines, who have contributed concepts and tools over more than six decades. As agricultural scientists now consider the next generation models, data, and knowledge products needed to meet the increasingly complex systems problems faced by society, it is important to take stock of this history and its lessons to ensure that we avoid re-invention and strive to consider all dimensions of associated challenges. To this end, we summarize here the history of agricultural systems modeling and identify lessons learned that can help guide the design and development of next generation of agricultural system tools and methods. A number of past events combined with overall technological progress in other fields have strongly contributed to the evolution of agricultural system modeling, including development of process-based bio-physical models of crops and livestock, statistical models based on historical observations, and economic optimization and simulation models at household and regional to global scales. Characteristics of agricultural systems models have varied widely depending on the systems involved, their scales, and the wide range of purposes that motivated their development and use by researchers in different disciplines. Recent trends in broader collaboration across institutions, across disciplines, and between the public and private sectors suggest that the stage is set for the major advances in agricultural systems science that are needed for the next generation of models, databases, knowledge products and decision support systems. The lessons from history should be considered

  12. Formal Modeling and Analysis of Timed Systems

    DEFF Research Database (Denmark)

    Larsen, Kim Guldstrand; Niebert, Peter

    This book constitutes the thoroughly refereed post-proceedings of the First International Workshop on Formal Modeling and Analysis of Timed Systems, FORMATS 2003, held in Marseille, France in September 2003. The 19 revised full papers presented together with an invited paper and the abstracts...... of two invited talks were carefully selected from 36 submissions during two rounds of reviewing and improvement. All current aspects of formal method for modeling and analyzing timed systems are addressed; among the timed systems dealt with are timed automata, timed Petri nets, max-plus algebras, real......-time systems, discrete time systems, timed languages, and real-time operating systems....

  13. Grey Box Modelling of Hydrological Systems

    DEFF Research Database (Denmark)

    Thordarson, Fannar Ørn

    The main topic of the thesis is grey box modelling of hydrologic systems, as well as formulation and assessment of their embedded uncertainties. Grey box model is a combination of a white box model, a physically-based model that is traditionally formulated using deterministic ordinary differential...... the lack of fit in state space formulation, and further support decisions for a model expansion. By using stochastic differential equations to formulate the dynamics of the hydrological system, either the complexity of the model can be increased by including the necessary hydrological processes...... in the model, or formulation of process noise can be considered so that it meets the physical limits of the hydrological system and give an adequate description of the embedded uncertainty in model structure. The thesis consists of two parts: a summary report and a part which contains six scientific papers...

  14. The Guided System Development Framework: Modeling and Verifying Communication Systems

    DEFF Research Database (Denmark)

    Carvalho Quaresma, Jose Nuno; Probst, Christian W.; Nielson, Flemming

    2014-01-01

    . The Guided System Development framework contributes to more secure communication systems by aiding the development of such systems. The framework features a simple modelling language, step-wise refinement from models to implementation, interfaces to security verification tools, and code generation from...... the verified specification. The refinement process carries thus security properties from the model to the implementation. Our approach also supports verification of systems previously developed and deployed. Internally, the reasoning in our framework is based on the Beliefs and Knowledge tool, a verification...

  15. System Advisor Model: Flat Plate Photovoltaic Performance Modeling Validation Report

    Energy Technology Data Exchange (ETDEWEB)

    Freeman, Janine [National Renewable Energy Lab. (NREL), Golden, CO (United States); Whitmore, Jonathan [National Renewable Energy Lab. (NREL), Golden, CO (United States); Kaffine, Leah [National Renewable Energy Lab. (NREL), Golden, CO (United States); Blair, Nate [National Renewable Energy Lab. (NREL), Golden, CO (United States); Dobos, Aron P. [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2013-12-01

    The System Advisor Model (SAM) is a free software tool that performs detailed analysis of both system performance and system financing for a variety of renewable energy technologies. This report provides detailed validation of the SAM flat plate photovoltaic performance model by comparing SAM-modeled PV system generation data to actual measured production data for nine PV systems ranging from 75 kW to greater than 25 MW in size. The results show strong agreement between SAM predictions and field data, with annualized prediction error below 3% for all fixed tilt cases and below 8% for all one axis tracked cases. The analysis concludes that snow cover and system outages are the primary sources of disagreement, and other deviations resulting from seasonal biases in the irradiation models and one axis tracking issues are discussed in detail.

  16. Coupling population dynamics with earth system models: the POPEM model.

    Science.gov (United States)

    Navarro, Andrés; Moreno, Raúl; Jiménez-Alcázar, Alfonso; Tapiador, Francisco J

    2017-09-16

    Precise modeling of CO 2 emissions is important for environmental research. This paper presents a new model of human population dynamics that can be embedded into ESMs (Earth System Models) to improve climate modeling. Through a system dynamics approach, we develop a cohort-component model that successfully simulates historical population dynamics with fine spatial resolution (about 1°×1°). The population projections are used to improve the estimates of CO 2 emissions, thus transcending the bulk approach of existing models and allowing more realistic non-linear effects to feature in the simulations. The module, dubbed POPEM (from Population Parameterization for Earth Models), is compared with current emission inventories and validated against UN aggregated data. Finally, it is shown that the module can be used to advance toward fully coupling the social and natural components of the Earth system, an emerging research path for environmental science and pollution research.

  17. Spinal Cord Injury Model System Information Network

    Science.gov (United States)

    ... the UAB-SCIMS Contact the UAB-SCIMS UAB Spinal Cord Injury Model System Newly Injured Health Daily Living Consumer ... Information Network The University of Alabama at Birmingham Spinal Cord Injury Model System (UAB-SCIMS) maintains this Information Network ...

  18. Statistical Model Checking for Stochastic Hybrid Systems

    DEFF Research Database (Denmark)

    David, Alexandre; Du, Dehui; Larsen, Kim Guldstrand

    2012-01-01

    This paper presents novel extensions and applications of the UPPAAL-SMC model checker. The extensions allow for statistical model checking of stochastic hybrid systems. We show how our race-based stochastic semantics extends to networks of hybrid systems, and indicate the integration technique ap...

  19. Systemic, Ecological Model for Rehabilitation Counseling.

    Science.gov (United States)

    Hershenson, David B.

    1998-01-01

    Presents a reformulation of Hershenson's theoretical model for rehabilitation counseling in systemic and ecological terms. This macrosystem is organized by precipitating event of disability and is composed of four systems: consumer, functional, provider, and contextual. Discusses the use of the model for selecting rehabilitation interventions…

  20. Modeling complex work systems - method meets reality

    NARCIS (Netherlands)

    van der Veer, Gerrit C.; Hoeve, Machteld; Lenting, Bert

    1996-01-01

    Modeling an existing task situation is often a first phase in the (re)design of information systems. For complex systems design, this model should consider both the people and the organization involved, the work, and situational aspects. Groupware Task Analysis (GTA) as part of a method for the

  1. System dynamics modelling of situation awareness

    CSIR Research Space (South Africa)

    Oosthuizen, R

    2015-11-01

    Full Text Available . The feedback loops and delays in the Command and Control system also contribute to the complex dynamic behavior. This paper will build on existing situation awareness models to develop a System Dynamics model to support a qualitative investigation through...

  2. Dynamic modeling of the INAPRO aquaponic system

    NARCIS (Netherlands)

    Karimanzira, Divas; Keesman, Karel J.; Kloas, Werner; Baganz, Daniela; Rauschenbach, Thomas

    2016-01-01

    The use of modeling techniques to analyze aquaponics systems is demonstrated with an example of dynamic modeling for the production of Nile tilapia (Oreochromis niloticus) and tomatoes (Solanum lycopersicon) using the innovative double recirculating aquaponic system ASTAF-PRO. For the management

  3. First measurements with new high-resolution gadolinium-GEM neutron detectors

    CERN Document Server

    Pfeiffer, Dorothea; Birch, Jens; Etxegarai, Maddi; Hall-Wilton, Richard; Höglund, Carina; Hultman, Lars; Llamas-Jansa, Isabel; Oliveri, Eraldo; Oksanen, Esko; Robinson, Linda; Ropelewski, Leszek; Schmidt, Susann; Streli, Christina; Thuiner, Patrik

    2016-05-17

    European Spallation Source instruments like the macromolecular diffractometer, NMX, require an excellent neutron detection efficiency, high-rate capabilities, time resolution, and an unprecedented spatial resolution in the order of a few hundred micrometers over a wide angular range of the incoming neutrons. For these instruments solid converters in combination with Micro Pattern Gaseous Detectors (MPGDs) are a promising option. A GEM detector with gadolinium converter was tested on a cold neutron beam at the IFE research reactor in Norway. The {\\mu}TPC analysis, proven to improve the spatial resolution in the case of $^{10}$B converters, is extended to gadolinium based detectors. For the first time, a Gd-GEM was successfully operated to detect neutrons with an estimated efficiency of 10% at a wavelength of 2 {\\AA} and a position resolution better than 350 {\\mu}m.

  4. Data Management and Other Logistical Challenges for the GEMS: The Data Coordinating Center Perspective

    Science.gov (United States)

    Biswas, Kousick; Carty, Christina; Horney, Rebecca; Nasrin, Dilruba; Farag, Tamer H.; Kotloff, Karen L.; Levine, Myron M.

    2012-01-01

    The Cooperative Studies Program Coordinating Center provided the data management, administrative, and statistical support to the Global Enteric Multicenter Study (GEMS). The GEMS study, the largest epidemiological study in the diarrheal disease area among children <5 years of age, was carried out in 4 African countries and 3 Asian countries. Given the geographical and geopolitical differences among the countries, the administration of a centralized data management operation was a major challenge. The sheer volume of the data that were collected, regular transfer of the data to a centralized database, and the cleaning of the same also posed some challenges. This paper outlines the details of the support that the data coordinating center provided and the challenges faced during the course of the study. PMID:23169938

  5. Aging measurements on triple-GEM detectors operated with $CF_{4}$-based gas mixtures

    CERN Document Server

    Alfonsi, M; De Simone, P; Murtas, F; Poli Lener, M P; Bonivento, W; Cardini, A; Raspino, D; Saitta, B; Pinci, D; Baccaro, S; 10.1016/j.nuclphysbps.2005.03.054

    2006-01-01

    We present the results of a global irradiation test of full size triple-GEM detectors operated with CF/sub 4/-based gas mixtures. This study has been performed in the framework of an R&D activity on detectors for the innermost region of the first muon station of the LHCb experiment. The prototypes have been irradiated at the Calliope facility of the ENEA-Casaccia with a high intensity 1.25 MeV detectors performances have been measured with X-rays and with a 3 Ge V pion beam at CERN. A SEM analysis on several samples of the detectors has been performed to complete the understanding of the physical processes occurring in a GEM detector during a strong irradiation.

  6. Aging measurements on triple-GEM detectors operated with $CF_{4}$- based gas mixtures

    CERN Document Server

    Alfonsi, M; Bencivenni, G; Bonivento, W; Cardini, A; Lener, M P; Murtas, F; Pinci, D; Raspino, D; Saitta, B; De Simone, P

    2004-01-01

    We present the results of a global irradiation test of full size triple-GEM detectors operated with CF/sub 4/-based gas mixtures. This study has been performed in the framework of an R&D activity on detectors for the innermost region of the first muon station of the LHCb experiment. The prototypes have been irradiated at the Calliope facility of the ENEA-Casaccia with a high intensity 1.25 MeV gamma from a /sup 60/Co source. After the irradiation test the detectors performances have been measured with X-rays and with a 3 GeV pion beam at CERN. A SEM analysis on several samples of the detectors has been performed to complete the understanding of the physical processes occurring in the GEM detector during the strong irradiation.

  7. Operational experience with the GEM detector assembly lines for the CMS forward muon upgrade

    CERN Document Server

    Vai, Ilaria

    2017-01-01

    The CMS Collaboration has been developing large-area Triple-GEM detectors to be installed in the muon endcap regions of the CMS experiment in 2019 to maintain forward muon trigger and tracking performance at the HL-LHC. Ten pre-production detectors were built at CERN to commission the first assembly line and the quality controls. These were installed in the CMS detector in early 2017 and are currently participating in the 2017 LHC run. The collaboration has prepared several additional assembly and quality control lines for distributed mass production of 160 GEM detectors at various sites worldwide. During 2017, these additional production sites have been optimizing construction techniques and quality control procedures and validating them against common specifications by constructing additional pre-production detectors. Using the specific experience from one production site as an example, we discuss how the quality controls make use of independent hardware and trained personnel to ensure fast and reliable pro...

  8. Aging measurements on triple-GEM detectors operated with CF{sub 4}-based gas mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Alfonsi, M. [Laboratori Nazionali di Frascati - INFN, Frascati (Italy); Bencivenni, G. [Laboratori Nazionali di Frascati - INFN, Frascati (Italy); De Simone, P. [Laboratori Nazionali di Frascati - INFN, Frascati (Italy); Murtas, F. [Laboratori Nazionali di Frascati - INFN, Frascati (Italy); Poli Lener, M. [Laboratori Nazionali di Frascati - INFN, Frascati (Italy); Bonivento, W. [Sezione INFN di Cagliari, Cagliari (Italy); Cardini, A. [Sezione INFN di Cagliari, Cagliari (Italy); Raspino, D. [Sezione INFN di Cagliari, Cagliari (Italy); Saitta, B. [Sezione INFN di Cagliari, Cagliari (Italy); Pinci, D. [Sezione INFN di Roma 1, Rome (Italy); Baccaro, S. [ENEA-FIS/ION, C.R. Casaccia, 00060, S. Maria di Galeria (Rome) (Italy)

    2006-01-15

    We present the results of a global irradiation test of full size triple-GEM detectors operated with CF{sub 4}-based gas mixtures. This study has been performed in the framework of an R and D activity on detectors for the innermost region of the first muon station of the LHCb experiment. The prototypes have been irradiated at the Calliope facility of the ENEA-Casaccia with a high intensity 1.25 MeV {gamma} {sup 6}Co source. After the irradiation test the detectors performances have been measured with X-rays and with a 3 GeV pion beam at CERN. A SEM analysis on several samples of the detectors has been performed to complete the understanding of the physical processes occurring in a GEM detector during a strong irradiation.

  9. Deoxygenative gem-difluoroolefination of carbonyl compounds with (chlorodifluoromethyltrimethylsilane and triphenylphosphine

    Directory of Open Access Journals (Sweden)

    Fei Wang

    2014-02-01

    Full Text Available Background: 1,1-Difluoroalkenes cannot only be used as valuable precursors for organic synthesis, but also act as bioisosteres for enzyme inhibitors. Among various methods for their preparation, the carbonyl olefination with difluoromethylene phosphonium ylide represents one of the most straightforward methods.Results: The combination of (chlorodifluoromethyltrimethylsilane (TMSCF2Cl and triphenylphosphine (PPh3 can be used for the synthesis of gem-difluoroolefins from carbonyl compounds. Comparative experiments demonstrate that TMSCF2Cl is superior to (bromodifluoromethyltrimethylsilane (TMSCF2Br and (trifluoromethyltrimethylsilane (TMSCF3 in this reaction.Conclusion: Similar to many other Wittig-type gem-difluoroolefination reactions in the presence of PPh3, the reaction of TMSCF2Cl with aldehydes and activated ketones is effective.

  10. Report from the II Melanoma Translational Meeting of the Spanish Melanoma Group (GEM)

    Science.gov (United States)

    Berrocal, Alfonso; Puig, Susana; Karachaliou, Niki; De Matos-Arruda, Leticia; Seoane, Joan; Escors, David; Alvarez, Carmen; Vaque, Jose Pedro; Prat, Aleix; Wellbrock, Claudia; Arozarena, Imanol; Marquez-Rodas, Ivan; Espinosa, Enrique; Molina, Migue Angel; Puertolas, Teresa; Juan-Otero, Manuel; Malagrida, Rosina; Jantus-Lewintre, Eloisa; Soriano, Virtudes; Arance, Ana; Manzano, Jose Luis; Lorigan, Paul; Gajewski, Thomas F.; Rosell, Rafael; Martin-Algarra, Salvador

    2017-01-01

    The II Melanoma Translational Meeting of the Spanish Melanoma Group (GEM) was held in Barcelona, Spain, at the Hospital Universitari Quiron-Dexeus on November 3rd, 2016. The conference featured leaders in the fields of oncology, immunology and dermatology, all working at both national and international levels on basic research with direct applications to the clinical setting. The objective was to present cutting edge research on melanoma, mainly from Spanish research groups, but also from some international groups, with the aim of generating a network for future national and international collaborations. During a single day, fifteen speakers, seven biologists and eight clinicians, with a special focus on translational research, outlined the main findings of their ongoing studies. The moderators in every session were recognized GEM oncologists who guided discussion from the clinical point of view regarding the preclinical data presented. Herein, we summarize the main topics discussed during the meeting.

  11. Formal heterogeneous system modeling with SystemC

    DEFF Research Database (Denmark)

    Niaki, Seyed Hosein Attarzadeh; Jakobsen, Mikkel Koefoed; Sulonen, Tero

    2012-01-01

    Electronic System Level (ESL) design of embedded systems proposes raising the abstraction level of the design entry to cope with the increasing complexity of such systems. To exploit the benefits of ESL, design languages should allow specification of models which are a) heterogeneous, to describe...... to focus on specifying the pure functional aspects. A key advantage is that the formalism is used to export the structure and behavior of the models via introspection as an abstract representation for further analysis and synthesis....

  12. Regression Models for Repairable Systems

    Czech Academy of Sciences Publication Activity Database

    Novák, Petr

    2015-01-01

    Roč. 17, č. 4 (2015), s. 963-972 ISSN 1387-5841 Institutional support: RVO:67985556 Keywords : Reliability analysis * Repair models * Regression Subject RIV: BB - Applied Statistics , Operational Research Impact factor: 0.782, year: 2015 http://library.utia.cas.cz/separaty/2015/SI/novak-0450902.pdf

  13. Mathematical Modeling Of Life-Support Systems

    Science.gov (United States)

    Seshan, Panchalam K.; Ganapathi, Balasubramanian; Jan, Darrell L.; Ferrall, Joseph F.; Rohatgi, Naresh K.

    1994-01-01

    Generic hierarchical model of life-support system developed to facilitate comparisons of options in design of system. Model represents combinations of interdependent subsystems supporting microbes, plants, fish, and land animals (including humans). Generic model enables rapid configuration of variety of specific life support component models for tradeoff studies culminating in single system design. Enables rapid evaluation of effects of substituting alternate technologies and even entire groups of technologies and subsystems. Used to synthesize and analyze life-support systems ranging from relatively simple, nonregenerative units like aquariums to complex closed-loop systems aboard submarines or spacecraft. Model, called Generic Modular Flow Schematic (GMFS), coded in such chemical-process-simulation languages as Aspen Plus and expressed as three-dimensional spreadsheet.

  14. Systematic modelling and simulation of refrigeration systems

    DEFF Research Database (Denmark)

    Rasmussen, Bjarne D.; Jakobsen, Arne

    1998-01-01

    The task of developing a simulation model of a refrigeration system can be very difficult and time consuming. In order for this process to be effective, a systematic method for developing the system model is required. This method should aim at guiding the developer to clarify the purpose of the s......The task of developing a simulation model of a refrigeration system can be very difficult and time consuming. In order for this process to be effective, a systematic method for developing the system model is required. This method should aim at guiding the developer to clarify the purpose...... of the simulation, to select appropriate component models and to set up the equations in a well-arranged way. In this paper the outline of such a method is proposed and examples showing the use of this method for simulation of refrigeration systems are given....

  15. Modeling and analysis of stochastic systems

    CERN Document Server

    Kulkarni, Vidyadhar G

    2011-01-01

    Based on the author's more than 25 years of teaching experience, Modeling and Analysis of Stochastic Systems, Second Edition covers the most important classes of stochastic processes used in the modeling of diverse systems, from supply chains and inventory systems to genetics and biological systems. For each class of stochastic process, the text includes its definition, characterization, applications, transient and limiting behavior, first passage times, and cost/reward models. Along with reorganizing the material, this edition revises and adds new exercises and examples. New to the second edi

  16. Essentials of econophysics modelling

    CERN Document Server

    Slanina, Frantisek

    2014-01-01

    This book is a course in methods and models rooted in physics and used in modelling economic and social phenomena. It covers the discipline of econophysics, which creates an interface between physics and economics. Besides the main theme, it touches on the theory of complex networks and simulations of social phenomena in general. After a brief historical introduction, the book starts with a list of basic empirical data and proceeds to thorough investigation of mathematical and computer models. Many of the models are based on hypotheses of the behaviour of simplified agents. These comprise strategic thinking, imitation, herding, and the gem of econophysics, the so-called minority game. At the same time, many other models view the economic processes as interactions of inanimate particles. Here, the methods of physics are especially useful. Examples of systems modelled in such a way include books of stock-market orders, and redistribution of wealth among individuals. Network effects are investigated in the inter...

  17. Formal heterogeneous system modeling with SystemC

    DEFF Research Database (Denmark)

    Niaki, Seyed Hosein Attarzadeh; Jakobsen, Mikkel Koefoed; Sulonen, Tero

    2012-01-01

    Electronic System Level (ESL) design of embedded systems proposes raising the abstraction level of the design entry to cope with the increasing complexity of such systems. To exploit the benefits of ESL, design languages should allow specification of models which are a) heterogeneous, to describe...

  18. Study of the spatial resolution of low-material GEM tracking detectors

    Directory of Open Access Journals (Sweden)

    Kudryavtsev V.N.

    2018-01-01

    Full Text Available The spatial resolution of GEM based tracking detectors has been simulated and measured. The simulation includes the GEANT4 based transport of high energy electrons with careful accounting for atomic relaxation processes including emission of fluorescent photons and Auger electrons and custom post-processing, including accounting for diffusion, gas amplification fluctuations, the distribution of signals on readout electrodes, electronics noise and a particular algorithm of the final coordinate calculation (center of gravity. The simulation demonstrates that a minimum of the spatial resolution of about 10 μm can be achieved with strip pitches from 250 μm to 300 μm. For larger pitches the resolution is quickly degrading reaching 80-100 μm at a pitch of 500 μm. The spatial resolution of low-material triple-GEM detectors for the DEUTRON facility at the VEPP-3 storage ring is measured at the extracted beam facility of the VEPP-4M collider. The amount of material in these detectors is reduced by etching the copper of the GEMs electrodes and using a readout structure on a thin kapton foil rather than on a glass fibre plate. The exact amount of material in one DEUTRON detector is measured by studying multiple scattering of 100 MeV electrons in it. The result of these measurements is X/X0 = 2.4×10−3 corresponding to a thickness of the copper layers of the GEM foils of 3 μm. The spatial resolution of one DEUTRON detector is measured with 500 MeV electrons and the measured value is equal to 35 ± 1 μm for orthogonal tracks.

  19. 100+ years of instrumental seismology: the example of the ISC-GEM Global Earthquake Instrumental Catalogue

    Science.gov (United States)

    Storchak, Dmitry; Di Giacomo, Domenico

    2015-04-01

    Systematic seismological observations of earthquakes using seismic instruments on a global scale began more than 100 years ago. Since then seismologists made many discoveries about the Earth interior and the physics of the earthquakes, also thanks to major developments in the seismic instrumentation deployed around the world. Besides, since the establishment of the first global networks (Milne and Jesuit networks), seismologists around the world stored and exchanged the results of routine observations (e.g., picking of arrival times, amplitude-period measurements, etc.) or more sophisticated analyses (e.g., moment tensor inversion) in seismological bulletins/catalogues. With a project funded by the GEM Foundation (www.globalquakemodel.org), the ISC and the Team of International Experts released a new global earthquake catalogue, the ISC-GEM Global Instrumental Earthquake Catalogue (1900 2009) (www.isc.ac.uk/iscgem/index.php), which, differently from previous global seismic catalogues, has the unique feature of covering the entire period of instrumental seismology with locations and magnitude re-assessed using modern approaches for the global earthquakes selected for processing (in the current version approximately 21,000). During the 110 years covered by the ISC-GEM catalogue many seismological developments occurred in terms of instrumentation, seismological practice and knowledge of the physics of the earthquakes. In this contribution we give a brief overview of the major milestones characterizing the last 100+ years of instrumental seismology that were relevant for the production of the ISC-GEM catalogue and the major challenges we faced to obtain a catalogue as homogenous as possible.

  20. Study of the spatial resolution of low-material GEM tracking detectors

    Science.gov (United States)

    Kudryavtsev, V. N.; Maltsev, T. V.; Shekhtman, L. I.

    2018-02-01

    The spatial resolution of GEM based tracking detectors has been simulated and measured. The simulation includes the GEANT4 based transport of high energy electrons with careful accounting for atomic relaxation processes including emission of fluorescent photons and Auger electrons and custom post-processing, including accounting for diffusion, gas amplification fluctuations, the distribution of signals on readout electrodes, electronics noise and a particular algorithm of the final coordinate calculation (center of gravity). The simulation demonstrates that a minimum of the spatial resolution of about 10 μm can be achieved with strip pitches from 250 μm to 300 μm. For larger pitches the resolution is quickly degrading reaching 80-100 μm at a pitch of 500 μm. The spatial resolution of low-material triple-GEM detectors for the DEUTRON facility at the VEPP-3 storage ring is measured at the extracted beam facility of the VEPP-4M collider. The amount of material in these detectors is reduced by etching the copper of the GEMs electrodes and using a readout structure on a thin kapton foil rather than on a glass fibre plate. The exact amount of material in one DEUTRON detector is measured by studying multiple scattering of 100 MeV electrons in it. The result of these measurements is X/X0 = 2.4×10-3 corresponding to a thickness of the copper layers of the GEM foils of 3 μm. The spatial resolution of one DEUTRON detector is measured with 500 MeV electrons and the measured value is equal to 35 ± 1 μm for orthogonal tracks.