dataesr/scientific-paragraphs-categorization huggingface dataset:
One property seems emerging in the design of groupware: tailorability. Hence, our aim on the long run is to integrate the concept of tailorability to design a more flexible groupware system. In fact, we aim at using Web services, which are nowadays widely used in the industry, along with ontologies for bringing semantic defini tions to software obj ects. Therefore, we want the behavior of the Collaborator agent to dy namically adapt to users' needs and preferences. This behavior should be created without hard coding and reexecuting the application, which consume time and eventually necessitate the intervention of an expert programmer instead of a normal end-user. We believe that these concepts will bring an innovative approach to design tailorable collaborative applications based on MAS, and hence shifting the multi agent concept from theoretical simulation to real practice in the industrial world.
Results After 25 000 generations in an unchanging environment (L-AND-R), treatments selected to maximize performance and minimize connection costs (P&CC) produce significantly more modular networks than treatments maximizing performance alone (PA) (figure 2d, Q ¼ 0. 42, 95% CI [0. 25,0. 45] vs. Q ¼ 0. 18[0. 16, 0. 19], p ¼ 8 Â 10 209 using Matlab's Mann -Whitney-Wilcoxon rank sum test, which is the default statistical test unless otherwise specified). To test whether evolved networks exhibit functional modularity corresponding to the left -right decomposition of the task we divide networks into two modules by selecting the division that maximizes Q and colour nodes in each partition differently. Left -right decomposition is visually apparent in most P&CC trials and absent in PA trials (figure  2e, f  ).
We tested two fully separable problems: one with five 'exclusive or' (XOR) logic modules (figure  5b ), and another with hierarchically nested XOR problems (figure  5c ). P&CC created separate modules for the decomposed problems in nearly every trial, whereas PA almost never did (see the electronic supplementary material, figures S2 and S3). P&CC performance was also significantly higher (figure  5b, c ), and there was an inverse correlation between cost and modularity (see the electronic supplementary material, figure  S10 ). After reading a preprint of this manuscript, a different research group replicated the main result in a different domain: they found that a connection cost causes modularity to evolve when optimizing computer chip architectures  [35]. Confirming the generality of the finding that connection costs improve adaptation rates and that high-performing, low-cost networks are modular is an interesting area for future research.
(b) Statistics For each statistic, we report the median +95% bootstrapped confidence intervals of the median (calculated by resampling the data 5000 times). In plots, these confidence intervals are smoothed with a median filter (window size ¼ 200) to remove sampling noise. Statistical significance is assessed using Matlab's Mann -Whitney -Wilcoxon rank sum test. For P&CC treatments, prior to calculating connection costs, we place nodes in positions optimal for minimizing connection costs given the topology of the network, which is biologically motivated  [17, 18, 29]  and can be solved for mathematically  [29]. Inputs and outputs are at fixed locations (see §4d). Visualizations reflect these node placements.
All of the experimental data, source code and analysis scripts are freely available in a permanent online archive at http://dx. doi. org/10. 5061/dryad. 9tb07. Funding provided by an NSF Postdoctoral Research Fellowship in Biology to J. C. (DBI-1003220) and NSF CDI Grant ECCS 0941561. J. B. M. is supported by the ANR ( project Creadapt ANR-12-JS03-0009). Thanks are due to Shimon Whiteson, Rafael Sanjuan, Stephane Doncieux, Dusan Misevic, Jeff Barrick, Charles Ofria and the reviewers for helpful comments.
We present an integrated photometric spectral energy distribution (SED) of the Magellanictype galaxy NGC 4449 from the far-ultraviolet (UV) to the submillimetre, including new observations acquired by the Herschel Space Observatory. We include integrated UV photometry from the Swift Ultraviolet and Optical Telescope using a measurement technique which is appropriate for extended sources with coincidence loss. In this paper, we examine the available multiwavelength data to infer a range of ages, metallicities and star formation rates for the underlying stellar populations, as well as the composition and the total mass of dust in NGC 4449. Our analysis of the global optical spectrum of NGC 4449 fitted using the spectral fitting code STARLIGHT suggests that the majority of stellar mass resides in old ( 1 Gyr old) and metal-poor (Z/Z ∼ 0.
In this paper, we describe a model of the wellknown starburst galaxy NGC 4449, which is a low-metallicity [log(O/H) + 12 = 8. 23, 1/3 Z ;  Engelbracht et al. 2008 ] actively star forming (SFR ∼ 0. 5 M yr -1 ;  Hill et al. 1998; Hunter et al. 1998)  barred Magellanic-type irregular galaxy  (de Vaucouleurs et al. 1991; Corwin, Buta & de Vaucouleurs 1994)  seen face-on. At a distance of 3. 8 Mpc  (Annibali et al. 2008 ) its H I envelope extends to 12. 9 kpc (11. 6 arcmin), equal to approximately three Holmberg radii  (Hunter, van Woerden & Gallagher 1999; Swaters et al. 2002) , and forms a pronounced system of streamers with a counter-rotating H I core, which may be indicative of past mergers  (Hunter et al. 1999; Theis & Kohle 2001). NGC 4449 is particularly suitable for multiwavelength studies because of its wide range of existing photometric data extending to the far-infrared (FIR).
The new observations acquired with the Spitzer Space Telescope  (Werner et al. 2004 ) and the Herschel Space Observatory  (Pilbratt et al. 2010 ) are essential in studying gas cooling processes and the properties of dust in the ISM of NGC 4449. In the following sections, we will discuss in detail a model of NGC 4449 based on multiple observational constraints and including a treatment of polycyclic aromatic hydrocarbons (PAHs). Thus, in Section 2 we describe the observations and data reduction techniques, and in Section 3 we describe the modelling method, as well as the assumptions and the convergence criteria adopted. The results and discussion are presented in Section 4, and the conclusions follow in Section 5. In a companion paper,  Karczewski et al. (in preparation, hereafter  Paper II), we study the FIR cooling lines and discuss properties of PDRs inferred from spatially resolved spectroscopic observations of NGC 4449.
Ultraviolet observations with GALEX and Swift At UV wavelengths NGC 4449 has been observed by two recent space-borne missions, GALEX (in two UV bands) and the Swift Ultraviolet/Optical Telescope (UVOT; in three UV and three optical bands). Standard aperture photometry using the inflight calibration of  Morrissey et al. (2007)  was performed on tile 5228 acquired as part of GALEX Nearby Galaxy Survey and accessible via General Release 6. The overall uncertainties include photometric repeatability measurements by  Morrissey et al. (2007). Swift/UVOT  (Roming et al. 2005)  offers four times the angular resolution of GALEX in three narrow UV bands. The telescope is equipped with a photon-counting detector and was originally designed to detect and observe gamma-ray bursts. As a consequence, standard data reduction procedures cannot be applied straightforwardly to observations of extended sources.
Optical observations with SDSS In addition to the optical fluxes derived from the Swift/UVOT observations, SDSS observations in five optical bands (u, g, r, i and z) are available as part of Data Release 7. NGC 4449 is contained entirely within one field, thus, minimizing deblending or sky subtraction issues which may arise in the case of extended sources. Standard aperture photometry was performed using elliptical apertures and the counts were converted into flux densities as described by  West et al. (2010). The uncertainties in the derived fluxes are dominated by uncertainties in sky determination and subtraction.
The quoted uncertainties include the calibration uncertainties at 5 per cent in all bands  (Müller et al. 2011a; Rémy-Ruyer et al. , in preparation). The SPIRE observations were performed as two orthogonal scans covering an area of 24 arcmin × 24 arcmin. The corresponding maps were reduced using a modified version of the SPIRE pipeline in HIPE. The steps up to Level 1 were identical to those in the Table  2. Summary of the derived photometric data for NGC 4449. All fluxes have been corrected for the foreground extinction using E(B -V) = 0. 019  (Schlegel, Finkbeiner & Davis 1998)  and the extinction law of  Cardelli, Clayton & Mathis (1989)  with R V = 3. 1. References: (1) this work; (2) 2MASS All-Sky Extended Source Catalog  (Skrutskie et al. 2006)  original pipeline provided by the SPIRE Instrument Control Center.
2MASS, WISE and Planck catalogue data Global 2MASS photometric measurements for NGC 4449 were taken from columns j_m_ext, h_m_ext and k_m_ext of the 2MASS All-Sky Extended Source Catalog, and were subsequently converted to flux densities using the zero-points tabulated by  Cohen, Wheaton & Megeath (2003). WISE photometry was taken from columns gmag and gerr of the WISE All-Sky Source Catalog. Colour correction was applied using interpolated correction factors suitable for a source emitting as ν -1. 18 across the four WISE bands. Planck photometry was taken from column GAUFLUX(_ERR) of the Early Release Compact Source Catalogue. Similarly, the interpolated colour correction factors used were suitable for a source emitting as ν 2. 80 across the Planck bands centred at 350, 550 and 850 µm.
2. In constructing our MOCASSIN model of NGC 4449 we have made simplifying assumptions about the geometry, gas density distribution, elemental abundances, dust composition and dust grain size distribution. We have also made assumptions about the SFH. In Section 3. 4, we discuss a general picture of the stellar populations in NGC 4449, obtained using the spectral decomposition code STARLIGHT. In Section 3. 7. 1, we characterize the youngest stellar population based on observational constraints. Finally, in Section 3. 7. 3, we fit the older populations taking into account the constraints from earlier sections. The fitting of the SFH and dust is performed almost simultaneously for self-consistency. Therefore, the young stellar population, the episodes of star formation and dust are never modelled on their own.
An upgrade to the ATLAS silicon tracker cooling control system may require a change from C 3 F 8 (octafluoro-propane) evaporative coolant to a blend containing 10-25 % of C 2 F 6 (hexafluoro-ethane). Such a change will reduce the evaporation temperature to assure thermal stability following radiation damage accumulated at full LHC luminosity. Central to this upgrade is a new ultrasonic instrument in which sound transit times are continuously measured in opposite directions in flowing gas at known temperature and pressure to deduce the C 3 F 8 /C 2 F 6 flow rate and mixture composition. The instrument and its Supervisory, Control and Data Acquisition (SCADA) software are described in this paper. Several geometries for the instrument are in use or under evaluation. An instrument with a 'pinched axial' geometry intended for analysis and measurement of moderate flow rates has demonstrated a mixture resolution of 3.
Introduction We describe a combined ultrasonic gas mixture analyzer/flow meter for continuous real time composition analysis of binary gas mixtures. The instrument can be used in many applications where knowledge of binary gas composition is required. The combined flow measurement and mixture analysis algorithm employs sound velocity measurements in two directions in combination with measurements of the pressure and temperature of the gas mixture being analyzed. The instrument -implemented in several geometries described in the following sections -is composed of a pair of ultrasonic transducers mounted within a gas enclosure intended for operation at elevated, atmospheric or sub-atmospheric pressures, together with custom measuring electronics and analyzing software. The development is motivated by a possible future upgrade of the ATLAS silicon tracker evaporative cooling system, in which the currently-used octafluoro-propane fluorocarbon evaporative coolant (R218, C 3 F 8 ; molecular weight = 188)  [1]  will be blended with the more volatile hexafluoro-ethane (R118, C 2 F 6 ; mw = 138).
The minimum pressures shown in table  1  correspond to those at the outputs of those heaters. In operation with C 3 F 8 /C 2 F 6 blends it will be necessary to monitor the C 3 F 8 /C 2 F 6 mixture ratio and if necessary to adjust it with the addition of more of either component. The mixture ratio is best monitored in the warm region of the vapour return tubing (far from the on-detector evaporative cooling channels) where the vapour mixture is in the superheated (single phase) state, simplifying sound velocity predictions. In table  1  the sound velocities at 20°C, 1 bar abs, calculated using the NIST-REFPROP package  [5]  are shown as examples. The sound velocity in a binary gas mixture at known temperature and pressure is a unique function of the molar concentration of the two components of differing molecular weight.
Ultrasonic binary gas analysis was first used in particle physics for the analysis of the N 2 /C 5 F 12 (dodecafluoro-pentane: mw = 288) Cherenkov gas radiator of the SLD Cherenkov Ring Imaging Detector  [6] , as a simpler alternative to on-line refractive index monitoring. Since then it has been adopted in all the major ring imaging Cherenkov detectors, including DELPHI, COMPASS and LHCb. The molar concentration of the two component vapours is determined from a comparison of sound velocity measurements with velocity-composition look-up table data gathered from prior measurements in calibration mixtures or from theoretical derivations made with an appropriate equation of state. The NIST-REFPROP package  [5]  is based on the most accurate pure fluid and mixture models currently available for a wide range of fluid combinations.
In the custom electronics sound bursts are sent in opposite directions which may be aligned with -or at an angle -to the gas flow. Rolling average transit times, temperature and pressure data continually stream from a FIFO memory to a supervisory computer presently via RS232, USB, and in future also by CANbus. The gas mixture and flow rate are continuously calculated using SCADA software implemented in PVSS-II  [8]. Transit times in both directions are used to compute the gas flow rate while the averages of the sound velocities in the two directions are used together with temperature and pressure to compute the binary gas composition by comparison with stored velocity vs. concentration look-up tables (Section 6). These tables may be created from prior measurements in calibration mixtures or from theoretical thermodynamic calculations.
The CFD simulation was made using the OpenFOAM® package  [9]  with the SST k-ω  [10]  turbulence model and a mesh of 545000 polyhedral cells, in order to evaluate the likely effect of the ultrasonic transducers, flow deflection and diameter reduction cones on the measurement precision. "Start condition" volume flows of 100 and 200 lmin -1 of C 3 F 8 at 1 bar abs and 20 °C (density ~ 7. 9 kgm -3 ), corresponded to transversally-averaged axial flow velocities of 1. 08 and 2. 16 ms -1 in the 44. 3mm ID "pinch" tube linking the transducers. The average velocity in the cylindrical volume defined by the transducer diameter and spacing has been estimated by CFD simulation and assumed to be representative of the velocity seen by the ultrasonic flowmeter. The CFD calculations, shown in figures 7 and 8 and in table 2, suggest a 9% underestimation of the real axial flow velocity due to: • a vortex trailing the upstream ultrasonic transducer within the 83 mm upstream reduction cone (figure  3 ) where the tube inner diameter shrinks from 72.
The precision of mixture determination, δ δ δ δ(mix), at any concentration of the two components is given by; ‫)ݔ݅݉(߲‬ = డ ( 5 ) where m is the local slope of the sound velocity/ concentration curve and δ δ δ δc is the uncertainty in the sound velocity measurement. For example, in a blend of 20 % C 2 F 6 in C 3 F 8 -the sound velocity uncertainty of 0. 05 ms -1 yields a concentration uncertainty ~0. 3 % at 20 %C 2 F 6 , where the slope of the velocity/ concentration curve is ~0. 18 ms -1 % -1. The precision of the sound velocity determinations of the NIST-REFPROP package  [5]  for C 2 F 6 and C 3 F 8 has been independently estimated in  [11] , as part of an extensive set of comparisons between calculated thermodynamic and thermophysical parameters and measurement data from a large number of source references for  20    sound velocity measurements made for each vapour by 2 groups.
Gas analyzer for sampling gas streams at very low flow rates In a second application related to the ATLAS evaporative cooling system, we use ultrasonic binary gas analysis to detect low levels of C 3 F 8 vapour leaking into the N 2 environmental gas surrounding the ATLAS pixel tracker. Gas is aspirated from the pixel tracker volume through an ultrasonic analysis tube with a vacuum pump, as shown in figure  10. A low flow of around 100 ml. min -1 is achievable through the (150 m long, 8 mm inner diameter) aspiration tube, with the analyzer tube operating at a pressure of 985 mbar abs ± 2 mbar. Exhaust gas from the analysis tube (typically containing > 99. 9 % N 2 ) is vented to an air extraction system for return to the surface. The analyzer has been in continuous operation since January 2010, and is locatedtogether with its data acquisition and supervisory computer -in a subterranean technical cavern alongside the ATLAS experimental cavern, whose floor is 92 m below the surface.
A valve selection panel allows future expansion to allow the envelope gases of the ATLAS silicon microstrip tracker (SCT) and inner detector volumes to be monitored. Additional analysis tubes are foreseen in the same rack to allow this, together with full automation of gas stream selection. Figure  11  compares measured sound velocities in molar mixtures of up to 10 % C 3 F 8 in N 2 with sound velocity predictions from the PC-SAFT equation of state  [7]. The data of figure  11  are abstracted from measurements and predictions made over the full concentration range from pure C 3 F 8 to pure N 2. The PC-SAFT equation of state was used as NIST-REFPROP is not presently configured for calculations of mixtures of saturated fluorocarbons with N 2. A typical reduction in sound velocity of 0. 86 ms -1 from that of pure nitrogen is typically observed when the full pixel detector cooling system of 88 independent circuits is fully operating.
The latter configuration with a pair of transverse tube stubs allows the changing of a transducer without interruption of the main gas flow: the transducers can be backed off outboard of quarter-turn ball valves, which when open allow the sound path to traverse the main tube. In configurations where the transducer spacing includes an element L' containing quasistatic vapour in communication with the flow in the main tube the formalism for calculating the flow velocity is modified from that of eq. (  6 ) as follows: ‫ݐ‬ ௗ௪ స ′ + ಾೌ ௦ఈ(ା௩௦ఈ) , ‫ݐ‬ ௨ స ′ + ಾೌ ௦ఈ(ି௩௦ఈ) (10) The sound velocity, c, is the physical root derived from the relations of eq. (  10 ) in terms of measurables L, D Main α, t up and t down : ܿ = ൫௧ ೠ ା ௧ ೢ ൯ቀଶ′ା ವ ಾೌ ೞഀ ቁ ±ඨ൫௧ ೠ ା ௧ ೢ ൯ మ ቀଶ′ା ವ ಾೌ ೞഀ ቁ మ ି ቆଵ'௧ ೠ ௧ ೢ ቀ′ା ವ ಾೌ ೞഀ ቁቇ ସ௧ ೠ ௧ ೢ (11) allowing the gas flow velocity, v, to be calculated as ‫ݒ‬ = ܿ ቀܿ‫ݐ‬ ௨ - ‫ܦ‬ ெ ‫ߙ݊݅ݏ‬ -‫ܮ‬ ′ ቁ ‫ߙݏܿ‬ ‫ݐܿ(‬ ௨ -‫ܮ‬ ′ ) (12a) or as ‫ݒ‬ = ܿ ቀ ‫ܦ‬ ெ ‫ߙ݊݅ݏ‬ + ‫ܮ‬ ′ -‫ݐܿ‬ ௗ௪ ቁ ‫ߙݏܿ‬ ‫ݐܿ(‬ ௗ௪ -‫ܮ‬ ′ ) (12b) CFD simulations were made using the OpenFOAM® package  [9] ,  [10] ,  [12]  to investigate the interaction between the vapour flow in the main tube and the placement of the ultrasonic transducers.
The ultrasonic interface board with the DC-DC conversion and energy storage capacitors for the transducer HV excitation is shown on the left of Figure  22b. Data is taken over a serial bus running under USB and RS232. Future versions will implement CANbus running the CANOpen communication protocol. The Supervisory, Control and Data Acquisition (SCADA) software -implemented as a PVSS-II project  [8] -sends various commands to the local electronics to start, stop or reset the instrument, and retrieve data from the FIFO memory. The analyzing software which processes the data, makes analyses and generates control signals to the electronics is described in section 6.
An expanded software version  [15]  will implement a C 3 F 8 /C 2 F 6 database covering a much larger c, T, P range, from near the critical temperature and pressure down to the expected thermosiphon condenser temperature and pressure of -70 ºC and 300 mbar abs (section 7). This development forms part of an ongoing study  [7] ,  [13]  to feed back improved C 3 F 8 /C 2 F 6 thermophysical data into NIST-REFRPOP  [5]  AND PC-SAFT models. The software will allow "zooming" to smaller sub-tables (O~10,000 c, T, P data points), corresponding to a narrower process range -as in the present application -in various C 3 F 8 /C 2 F 6 mixtures. The expanded database will also include air/fluorocarbon mixtures over a temperature and pressure range centred on thermosiphon condenser conditions. This database will provide a look up table to determine the level of air ingress into the sub-atmospheric pressure condenser.
Conclusion We have developed a combined, real-time ultrasonic flow meter and binary gas analyzer with custom electronics and dedicated SCADA software running under PVSS-II, a CERN standard. One version of the instrument has demonstrated a resolution of 3. 10 -3 for C 3 F 8 /C 2 F 6 mixtures with ~20 %C 2 F 6 , and a flow precision of 2 % of full scale for fluorocarbon mass flows up to 30 gs -1. A second version has been in long term use (over more than 1 year) to monitor C 3 F 8 leaks into part of the ATLAS silicon tracker nitrogen envelope. Sensitivity to C 3 F 8 leak concentrations of < 5. 10 -5 has been seen in this instrument. Several geometries for the instrument are in use or under evaluation. These include a 'pinched axial' sound path geometry for analysis and measurement of moderate flow rates, and an angled sound path geometry for analysis and measurement of high fluorocarbon flow rates of ~1.
Acknowledgments The authors wish to thank  CERN  and their home institutes for support for this project. University of Indiana participation was supported through  U. S. Department of Energy  contract  DE-AC02-98CH10886. University of Oklahoma participation was supported through  DOE  contract  DE-FG02-04ER41305. A. Bitadze  acknowledges support for his PhD research from the  ATLAS inner detector group  and the particle physics group of the  University of Glasgow. R. Bates  acknowledges support from the  UK Science and Technology Facilities Council. M. Doubek ,  V. Vacek  and  M. Vitek  acknowledge individual support and support for this project through the following grants in the Czech Republic: MSM grants  6840770035 & LA08015  and  SGS/FIS grant10-802460  of the  Czech Technical University, Prague.