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1
Fierlinger, Katharina M. "Massive stars shaping the ISM." Diss., Ludwig-Maximilians-Universität München, 2014. http://nbn-resolving.de/urn:nbn:de:bvb:19-176288.
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Diese Arbeit befasst sich mit dem Einfluss von Sternen, deren Masse acht Sonnenmassen übersteigt, auf das Interstellare Medium in ihrer Umgebung. Solche massereiche Sterne beenden ihr Dasein mit einer Supernovaexplosion und verlieren im Laufe ihrer - verglichen mit massearmen Sternen - raschen Entwicklung einen großen Teil ihrer Masse über ihre starken Sternwinde. Beispielsweise gibt ein Stern mit 60 Sonnenmassen Anfangsmasse mehr als die doppelte Supernovaenergie über die kinetische Energie seiner Winde in seine Umgebung ab.
Sterne entstehen in Regionen mit kaltem, dichtem Gas, den sogenannten Molekülwolken. Beobachtungen zeigen, dass diese Gaswolken turbulent sind. Es ist allerdings noch ungeklärt, woher die beobachtete Turbulenz im Interstellaren Medium ihre Energie bezieht. Die Energieabgabe von massereichen Sternen ist - neben großskaligen gravitativen Instabilitäten in der Scheibe der Milchstraße - eine der möglichen Erklärungen. Beobachtungen erlauben Rückschlüsse auf die eingebrachte Energiemenge und die Längenskalen des Energie liefernden Prozesses. Daher ist es relevant, zu bestimmen, wie viel kinetische Energie ein massereicher Stern in der ihn umgebenden Molekülwolke deponieren kann.
Der Schwerpunkt dieser Arbeit sind hydrodynamische Simulationen, die diese Energieeffizienz testen. Dazu wurden aktuelle Sternentwicklungsmodelle in die frei zugänglichen Eulerschen Gittercodes Pluto und Ramses eingebaut. Die Simulationen verwenden das von Eva Ntormousi erstellte Modul für die Berechnung der Heiz- und Kühlprozesse eines Multiphasenmediums.
Die Modellrechnungen führten zur Erkenntnis, dass in jener Phase der Simulation, in der die räumliche Auflösung der Modellrechnung die Eneergieeffizienz stark beeinflusst, der größte Energieverlust durch Strahlung an jener Stelle auftritt, an der das vom Stern ausgestoßene Material auf das aufgesammelte Umgebungsgas trifft. An dieser Kontaktfläche treten Mischungsprozesse auf, welche die Energieverluste steigern. Somit können unsere Simulationen in Kombination mit einer Abschätzung der Effizienz und Skalenlänge dieser Mischprozesse eine Aussage treffen, wie viel Energie massereiche Sterne zur Aufrechterhaltung der Turbulenz beitragen können. Für diese Abschätzung der Mischprozesse liefert die Literatur auf Beobachtungen und numerischen Simulationen basierende Richtwerte.
Als Anwendungsbeispiel wird in dieser Arbeit die Orion-Eridanus Region diskutiert. In dieser Region wird das radioaktive Isotop 26-Al beobachtet. Dieses Isotop wird vorrangig in massereichen Sternen gebildet. Es kann daher als Indikator für von Sternen ausgestoßene Materie verwendet werden. Interessanterweise zeigen die Beobachtungen dieser Region nur in einem Teil des Gebiets mit Röntgenemission ein 26-Al Signal. Unsere Ramses Modelle berücksichtigen 26-Al und können daher auf Gebiete mit (fehlenden) Korrelationen zwischen Röntgenemission und 26-Al Signal durchsucht werden.
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Harju, J., F. Daniel, O. Sipilae, P. Caselli, J. E. Pineda, R. K. Friesen, A. Punanova, et al. "Deuteration of ammonia in the starless core Ophiuchus/H-MM1." EDP SCIENCES S A, 2017. http://hdl.handle.net/10150/624367.
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Context. Ammonia and its deuterated isotopologues probe physical conditions in dense molecular cloud cores. The time-dependence of deuterium fractionation and the relative abundances of different nuclear spin modifications are supposed to provide a means of determining the evolutionary stages of these objects. Aims. We aim to test the current understanding of spin-state chemistry of deuterated species by determining the abundances and spin ratios of NH2D, NHD2 and ND3 in a quiescent, dense cloud. Methods. Spectral lines of NH3, NH2D, NHD2, ND3 and N2D+ were observed towards a dense, starless core in Ophiuchus with the APEX, GBT and IRAM 30-m telescopes. The observations were interpreted using a gas-grain chemistry model combined with radiative transfer calculations. The chemistry model distinguishes between the different nuclear spin states of light hydrogen molecules, ammonia and their deuterated forms. Different desorption schemes can be considered. Results. High deuterium fractionation ratios with NH2D = NH3 similar to 0 : 4, NHD2 = NH2D similar to 0 : 2 and ND3 = NHD2 similar to 0 : 06 are found in the core. The observed ortho/para ratios of NH2D and NHD2 are close to the corresponding nuclear spin statistical weights. The chemistry model can approximately reproduce the observed abundances, but consistently predicts too low ortho/para-NH2D, and too large ortho/para-NHD2 ratios. The longevity of N2H+ and NH3 in dense gas, which is prerequisite to their strong deuteration, can be attributed to the chemical inertia of N-2 on grain surfaces. Conclusions. The discrepancies between the chemistry model and the observations are likely to be caused by the fact that the model assumes complete scrambling in principal gas-phase deuteration reactions of ammonia, which means that all the nuclei are mixed in reactive collisions. If, instead, these reactions occur through proton hop/hydrogen abstraction processes, statistical spin ratios are to be expected. The present results suggest that while the deuteration of ammonia changes with physical conditions and time, the nuclear spin ratios of ammonia isotopologues do not probe the evolutionary stage of a cloud.
3
Kissmann, Ralf. "Numerical investigation of the turbulent ISM." [S.l.] : [s.n.], 2007. http://deposit.ddb.de/cgi-bin/dokserv?idn=98361265X.
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Noack, Vanessa. "Heroic Soldier-ism: Beautified Power Asymmetry." Thesis, Linköpings universitet, Institutionen för tema, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-166690.
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The Swedish Armed Forces can be considered a hegemonic masculine organisation with deeply embedded patterns of patriarchy, as well as fratriarchy represented by notions of homogeneity and the male soldier. Women are highly underrepresented and face multiple double standards related to their performance of gender and more precisely performance of femininity. However, the Swedish Armed Forces claim to be an inclusive organisation and advertise this through different recruiting strategies, which display women in uniforms. This thesis uses the methodology of qualitative research by combining the methods of critical discourse analysis and critical visual analysis to analyse the representation and the performativity of gender in a recruiting advertisement for inclusivity by the Swedish Armed Forces. I argue that this advertisement led to a certain form of reproducing stereotypical notions of femininity by representing women who embody certain requirements connected to beauty standards. At the same time, notions of hegemonic masculinity and patriarchy are challenged through the representation of women in military uniforms.
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Gan, Kok Chek. "A Java implementation of Peer ISM /." Leeds, 2001. http://www.leeds.ac.uk/library/counter2/compstmsc/20002001/gan%5Fpdf.zip.
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Menacho, Veronica. "The violent ISM in Haro 11." Licentiate thesis, Stockholms universitet, Institutionen för astronomi, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-163310.
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This thesis introduces briefly physical processes operating in the ISM around massive starsand focuses on the impact strong stellar feedback has in creating large-scale structures in a galaxy.Stellar feedback is ubiquitous in star forming galaxies and its effect on the ISM depends strongly on the energy output from the most massive stars (M$\geq$7 \Mo ) and the properties of the surrounding gas. Starburst galaxies are among the most active in producing %galaxies are among the most active galaxies and produce a large amount of massive star clusters %or even super star clusters (SSC; M$_{cl} \geq 10^5$ \Mo ), with stellar populations up to thousands of massive stars. %The most massive stars (M$\geq$30 \Mo ) are lives short, but they In the first 4 Myr of the star clusters evolution, radiative feedback of the most massive stars (M$\geq$30 \Mo ) are at work. Large amount of ionizing photons are released to the ambient medium while radiative pressure compress the surrounding gas. At the same time their stellar winds inject continuously mechanical energy and momentum in their surrounding. This mechanical feedback is then at later ages, until $\sim$ 40 Myrs, maintained by supernova explosions from the less massive stars. Strong stellar feedback tends to develop large-scale structures such as bubbles, loops, filaments and outflows. These are transient structures and can be seen as imprints of how the released energy is clearing or has cleared paths in the ISM. Strong stellar feedback can have devastating consequences in dwarf galaxies due to their shallow gravitational potential. It can accelerate outflows with velocities larger than their escape velocities. In this way, dwarf galaxies can lose a large fraction of their gas mass, which will be crucial in their subsequent evolution.On the other hand, galactic winds might be responsible to create holes in the ISM, allowing the easily-absorbed ionizing photons (Lyman continuum photons, LyC) to escape the galaxy. Studies on a few LyC leaking galaxies have shown that this mechanisms might have preference from a density-bound scenario, which takes place in galaxies with a highly ionized halo. In my paper I used deep MUSE observations to analyse the impact strong stellar feedback has in the starburst and Lyman continuum emitting galaxy: Haro 11. The paper presents three emission line diagnostics aiming to analyse the condition of the warm ionized gas in this galaxy, which are the \Ha\ emission, the level of ionization in gas and the presence of fast shocks. These diagnostics are presented in maps of 50 \kms\ bins in a velocity range from -400 to 350 \kms . Haro 11 shows a violent ISM whose warm ionized gas is almost completely shaped by effect of stellar feedback from the most massive star forming regions in the centre. Arcs, shells, outflows paths and galactic scale ionizing cones are imprinted in ISM of Haro 11. Our analysis suggests the presence of a kpc-scale superbubble which might have created galactic holes in the ISM. Beside of that, Haro 11 shows a highly ionized halo. Both mechanisms appear to facilitate the escape of LyC in this galaxy. %Finally, we observe emission at velocities up to thousand \kms\ which could hints to gas escaping the galaxy. Finally the paper presents estimates of the gas mass fraction that could escape the gravitational potential of the galaxy.
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Čanda, Pavel. "Bezdrátový přenos dat v pásmu ISM." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2011. http://www.nusl.cz/ntk/nusl-219136.
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Wireless extension of serial communication of RS232 standard, with using RF transceivers RFM12BP type, with transmissions errors correction. Device will be batery powered and low power consumption is required.
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Zapletal, Ondřej. "Nositelné antény pracující v ISM pásmu." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2016. http://www.nusl.cz/ntk/nusl-242011.
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Presented thesis is oriented on wearable antennas. The main aim of this thesis is to introduce the basic properties, measurement of textile’s electric properties and several manufacturing methods. The antenna design for the ISM 5.8 GHz bandwidth is also included and further observed by numerical model in CST Microwave Studio. The impact of flexibility and the influence of human tissue are evaluated in the case of designed equipment. According to the optimized design was made several samples by various technologies and samples were measured. Achieved results are further compared to equivalent results listed in actual available references.
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Dale, D. A., D. O. Cook, H. Roussel, J. A. Turner, L. Armus, A. D. Bolatto, M. Boquien, et al. "Updated 34-band Photometry for the SINGS/KINGFISH Samples of Nearby Galaxies." IOP PUBLISHING LTD, 2017. http://hdl.handle.net/10150/624375.
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We present an update to the ultraviolet-to-radio database of global broadband photometry for the 79 nearby galaxies that comprise the union of the KINGFISH (Key Insights on Nearby Galaxies: A Far-Infrared Survey with Herschel) and SINGS (Spitzer Infrared Nearby Galaxies Survey) samples. The 34-band data set presented here includes contributions from observational work carried out with a variety of facilities including GALEX, SDSS, Pan-STARRS1, NOAO, 2MASS, Wide-Field Infrared Survey Explorer, Spitzer, Herschel, Planck, JCMT, and the VLA. Improvements of note include recalibrations of previously published SINGS BVRCIC and KINGFISH farinfrared/submillimeter photometry. Similar to previous results in the literature, an excess of submillimeter emission above model predictions is seen primarily for low-metallicity dwarf or irregular galaxies. This 33-band photometric data set for the combined KINGFISH+SINGS sample serves as an important multiwavelength reference for the variety of galaxies observed at low redshift. A thorough analysis of the observed spectral energy distributions is carried out in a companion paper.
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Bieging, John H., Saahil Patel, William L. Peters, L. Viktor Toth, Gábor Marton, and Sarolta Zahorecz. "THE ARIZONA RADIO OBSERVATORY CO MAPPING SURVEY OF GALACTIC MOLECULAR CLOUDS. V. THE SH2-235 CLOUD IN CO J = 2 − 1, 13 CO J = 2 − 1, AND CO J = 3 − 2." IOP PUBLISHING LTD, 2016. http://hdl.handle.net/10150/621984.
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We present the results of a program to map the Sh2-235 molecular cloud complex in the CO and (CO)-C-13 J = 2 - 1 transitions using the Heinrich Hertz Submillimeter Telescope. The map resolution is 38 '' (FWHM), with an rms noise of 0.12K brightness temperature, for a velocity resolution of 0.34 km s(-1). With the same telescope, we also mapped the CO J = 3 - 2 line at a frequency of 345 GHz, using a 64 beam focal plane array of heterodyne mixers, achieving a typical rms noise of 0.5 K brightness temperature with a velocity resolution of 0.23 km s(-1). The three spectral line data cubes are available for download. Much of the cloud appears to be slightly sub-thermally excited in the J = 3 level, except for in the vicinity of the warmest and highest column density areas, which are currently forming stars. Using the CO and (CO)-C-13. J = 2 - 1 lines, we employ an LTE model to derive the gas column density over the entire mapped region. Examining a 125 pc(2). region centered on the most active star formation in the vicinity of Sh2-235, we find that the young stellar object surface density scales as approximately the 1.6-power of the gas column density. The area distribution function of the gas is a steeply declining exponential function of gas column density. Comparison of the morphology of ionized and molecular gas suggests that the cloud is being substantially disrupted by expansion of the H II regions, which may be triggering current star formation.
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Rho, J., J. W. Hewitt, J. Bieging, W. T. Reach, M. Andersen, and R. Güsten. "DISCOVERY OF BROAD MOLECULAR LINES AND OF SHOCKED MOLECULAR HYDROGEN FROM THE SUPERNOVA REMNANT G357.7+0.3: HHSMT, APEX, SPITZER , AND SOFIA OBSERVATIONS." IOP PUBLISHING LTD, 2016. http://hdl.handle.net/10150/622645.
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We report a discovery of shocked gas from the supernova remnant (SNR) G357.7+0.3. Our millimeter and submillimeter observations reveal broad molecular lines of CO(2-1), CO(3-2), CO(4-3), (CO)-C-13 (2-1), and (CO)-C-13 (3-2), HCO+, and HCN using the Heinrich Hertz Submillimeter Telescope, the Arizona 12 m Telescope, APEX, and the MOPRA Telescope. The widths of the broad lines are 15-30 km s(-1), and the detection of such broad lines is unambiguous, dynamic evidence showing that the SNR G357.7+0.3 is interacting with molecular clouds. The broad lines appear in extended regions (>4'.5 x 5'). We also present the detection of shocked H-2 emission in the mid-infrared but lacking ionic lines using Spitzer/IRS observations to map a few-arcminute area. The H2 excitation diagram shows a best fit with a two-temperature local thermal equilibrium model with the temperatures of similar to 200 and 660 K. We observed [C II] at 158 mu m and high-J CO(11-10) with the German Receiver for Astronomy at Terahertz Frequencies (GREAT) on the Stratospheric Observatory for Infrared Astronomy. The GREAT spectrum of [C II], a 3 sigma detection, shows a broad line profile with a width of 15.7 km(-1) that is similar to those of broad CO molecular lines. The line width of [C II] implies that ionic lines can come from a low-velocity C-shock. Comparison of H2 emission with shock models shows that a combination of two C-shock models is favored over a combination of C- and J-shocks or a single shock. We estimate the CO density, column density, and temperature using a RADEX model. The best-fit model with n(H-2) = 1.7 x 10(4) cm(-3), N(CO) = 5.6 x 10(16) cm(-2), and T = 75 K can reproduce the observed millimeter CO brightnesses.
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Kamenetzky, J., N. Rangwala, J. Glenn, P. R. Maloney, and A. Conley. "L '(CO)/L-FIR RELATIONS WITH CO ROTATIONAL LADDERS OF GALAXIES ACROSS THE HERSCHEL SPIRE ARCHIVE." IOP PUBLISHING LTD, 2016. http://hdl.handle.net/10150/621957.
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We present a catalog of all CO (J = 4-3 through J = 13-12), [ C I], and [ N II] lines available from extragalactic spectra from the Herschel SPIRE Fourier Transform Spectrometer (FTS) archive combined with observations of the low-J CO lines from the literature and from the Arizona Radio Observatory. This work examines the relationships between L-FIR, L'(CO), and L-CO/L-CO,L-1-0. We also present a new method for estimating probability distribution functions from marginal signal-to-noise ratio Herschel FTS spectra, which takes into account the instrumental "ringing" and the resulting highly correlated nature of the spectra. The slopes of log(L-FIR) versus log (L'(CO)) are linear for all mid- to high-J CO lines and slightly sublinear if restricted to (ultra) luminous infrared galaxies ((U) LIRGs). The mid-to high-J CO luminosity relative to CO J - 1-0 increases with increasing L-FIR, indicating higher excitement of the molecular gas, although these ratios do not exceed similar to 180. For a given bin in L-FIR, the luminosities relative to CO J = 1-0 remain relatively flat from J = 6-5 through J = 13-12, across three orders of magnitude of L-FIR. A single component theoretical photodissociation region (PDR) model cannot match these flat SLED shapes, although combinations of PDR models with mechanical heating added qualitatively match the shapes, indicating the need for further comprehensive modeling of the excitation processes of warm molecular gas in nearby galaxies.
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Svoboda, Brian E., Yancy L. Shirley, Cara Battersby, Erik W. Rosolowsky, Adam G. Ginsburg, Timothy P. Ellsworth-Bowers, Michele R. Pestalozzi, et al. "THE BOLOCAM GALACTIC PLANE SURVEY. XIV. PHYSICAL PROPERTIES OF MASSIVE STARLESS AND STAR-FORMING CLUMPS." IOP PUBLISHING LTD, 2016. http://hdl.handle.net/10150/621258.
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We sort 4683 molecular clouds between 10 degrees < l < 65 degrees from the Bolocam Galactic Plane Survey based on observational diagnostics of star formation activity: compact 70 mu m sources, mid-IR color-selected YSOs, H2O and CH3OH masers, and UCH II. regions. We also present a combined NH3-derived gas kinetic temperature and H2O maser catalog for 1788 clumps from our own GBT 100 m observations and from the literature. We identify a subsample of 2223 (47.5%) starless clump candidates (SCCs), the largest and most robust sample identified from a blind survey to date. Distributions of flux density, flux concentration, solid angle, kinetic temperature, column density, radius, and mass show strong (>1 dex) progressions when sorted by star formation indicator. The median SCC is marginally subvirial (alpha similar to 0.7) with >75% of clumps with known distance being gravitationally bound (alpha < 2). These samples show a statistically significant increase in the median clump mass of Delta M similar to 170-370 M-circle dot from the starless candidates to clumps associated with protostars. This trend could be due to (i) mass growth of the clumps at (M) over dot similar to 200-440 M-circle dot Myr(-1) for an average freefall 0.8 Myr timescale, (ii) a systematic factor of two increase in dust opacity from starless to protostellar phases, and/or (iii). a variation in the ratio of starless to protostellar clump lifetime that scales as similar to M-0.4. By comparing to the observed number of CH3OH maser containing clumps, we estimate the phase. lifetime of massive (M > 10(3) M-circle dot) starless clumps to be 0.37 +/- 0.08 Myr (M/10(3) M-circle dot)(-1); the majority (M < 450 M-circle dot) have phase. lifetimes longer than their average freefall time.
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Seo, Youngmin, and Youngmin Seo. "The L1495-B218 Filaments in Taurus Seen in NH₃ & CCS and Dynamical Stability of Filaments and Dense Cores." Diss., The University of Arizona, 2016. http://hdl.handle.net/10150/621572.
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We present deep NH₃ and CCS maps of L1495-B218 filaments and the dense cores embedded within the filaments in Taurus. The L1495-B218 filaments form an interconnected, nearby, large complex extending over 8 pc. We observed the filaments in NH₃ (1,1)&(2,2), CCS Nⱼ = 1₂-0₁, and HC₇N J = 21-20 with spectral resolution of 0.038 km/s and spatial resolution of 31". The CSAR algorithm, which is a hybrid of seeded-watershed and binary dendrogram algorithm, identifies 39 leaves and 16 branches in NH₃ (1,1). Applying a virial analysis for the 39 NH₃ leaves, we find only 9 out of 39 leaves are gravitationally bound, and 12 out of 30 gravitationally unbound leaves are pressure-confined. Our analysis suggests that a dense core may form as a pressure-confined structure, evolve to a gravitationally bound core, and then undergo collapse to form a protostar. We find that the L1495A, B213E, and B216 regions have strong CCS emission and the B211 and B218 regions have weak CCS emission. Analysis of CCS emission with NH₃ (1,1) and dust continuum emission shows that CCS is not a good tracer for starless core evolution. On the other hand, CCS appears to trace recently accreted gas in L1495A and L1521D. We also present more realistic dynamic stability conditions for dense cores and filaments. In a new analysis of stability conditions we account for converging motions which have been modeled toward starless cores and take the effect of radiation fields. We find that the critical size of a dense core having a homologous converging motion with its peak speed being the sound speed is roughly half of the critical size of the Bonnor-Ebert sphere. We also find the critical mass/line density of a dense core/filament irradiated by radiation to be considerably smaller than that of the Bonnor-Ebert sphere/isothermal cylinder when the radiation pressure is stronger than the central gas pressure of dense core/isothermal cylinder. For regions in the inner Galaxy and near OB associations, the critical mass/line density of a dense structure may be less than 20% of the critical mass/line density of Bonnor-Ebert sphere/isothermal cylinder.
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Puschnig, Johannes. "How ISM properties drive Lyman Continuum Escape." Licentiate thesis, Stockholms universitet, Institutionen för astronomi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-136349.
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The thesis introduces physical processes that are at work in astrophysical plasmas and reviews the current state of research related to the emission of ionizing photons, i.e. Lyman continuum (LyC). Star forming galaxies and active galactic nuclei are discussed as sources of LyC. Observations of LyC leakage at all redshifts are summarized and escape fractions are brought into a cosmological context, i.e. its implications for the reionization of the Universe, one of the major gas phase changes that was completed already after ∼1Gyr after the Big Bang at redshift z∼6.The main work focuses on observations of the local LyC leaking galaxy Tololo 1247-232. Physical properties of the interstellar medium, its porosity and neutral medium column density, could be derived using newly obtained Hubble Space Telescope (HST) data. The work is based on spectroscopy obtained with the Cosmic Origins Spectrograph (COS), as well as optical and ultraviolet multi-band imaging with the Wide Field Camera 3 (WFC3). An improved COS data reduction procedure was adopted. The recent detection of ionizing radiation emerging from Tololo 1247-232 could be confirmed. A LyC escape fraction of 6.6% was derived, in agreement with previous results. We used FUV absorption lines of Si II and Si IV as a probe of the neutral and ionized interstellar medium and find that most of the ISM gas is ionized, likely facilitating LyC escape from density bounded regions. Neutral gas covering as a function of line-of-sight velocity is derived using the apparent optical depth method. The ISM is found to be sufficiently clumpy, supporting the direct escape of LyC photons. We further report on broadband UV and optical continuum imaging as well as narrowband imaging of Lyα, Hα and Hβ. We also performed VLA 21cm imaging. The hydrogen hyperfine transition was not detected, but a deep upper limit atomic gas mass of 10^9 Mo could be derived. The upper limit gas fraction is only 20 percent. Evidence is found that the H I gas halo is relatively small compared to other Lyman Alpha emitters.
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Harris, Lee M. (Lee Mark) Carleton University Dissertation English. "Fighting duel-ism: a Glenn Gould context." Ottawa, 1993.
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Frecer, Petr. "Radiokomunikační monitor pro ISM pásmo 868 MHz." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2012. http://www.nusl.cz/ntk/nusl-219885.
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This thesis deals with the design and the realization of the radiocommunication monitor for the 868 MHz band. In the thesis, a description of licence-free radio bands complying ITU recommendations and ETSI standards is given. A special attention is paid to the 863 MHz - 870 MHz band. The transceiver CC1020 that forms the base for the monitor is described in detail. The circuit design, the monitor assembly and the firmware creation are presented step by step. The radiocommunication monitor is portable and battery powered. The monitor is able to display RF signals in the 868 MHz band, to indicate the frequency error of the transmitter and to receive FSK modulated signal. Demodulated data can be transferred to the personal computer via the USB.
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CASU, SERGIO. "Innovative ISM and Diagnostic Applications of Microwaves." Doctoral thesis, Università degli Studi di Cagliari, 2019. http://hdl.handle.net/11584/260389.
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The widest employment of electromagnetic (EM) waves is probably in the telecommunication
area. Nevertheless, the potential of electromagnetism goes beyond telecommunication
and can find application in a variety of fields. Structures such as antennas and
resonant cavities allow the generation of well-known EM fields that is possible to use in a
controlled way. In this thesis, different uses of EM field are proposed, involving different
areas. As a high power application, in the agriculture sector, a model to evaluate the
feasibility of using EM waves to disinfect the superficial layer of the soil is presented. The
variation of the dielectric constant due to the raise in temperature is taken into account
and power and time of irradiation to obtain the desired profile of temperature of the soil
is determined. A medium power application uses a resonant cavity as a (temperature)
controlled environment in which an enzymatic reaction takes place in an aqueous solution.
The yield of the reaction is compared with the yield obtained using conventional
heating. As a low power application, healthcare sector is considered, and the design of
an array of coil on a flexible substrate for magnetic resonance is presented. Furthermore,
a numerical evaluation of the EM field, inside a full blood bag, is carried out, to compare
it with the EM field generated by an RFID reader intended to be used for identification
of blood bags.
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Imara, Nia, Charles Lada, John Lewis, John H. Bieging, Shuo Kong, Marco Lombardi, and Joao Alves. "X Marks the Spot: Nexus of Filaments, Cores, and Outflows in a Young Star-forming Region." IOP PUBLISHING LTD, 2017. http://hdl.handle.net/10150/624336.
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We present a multiwavelength investigation of a region of a nearby giant molecular cloud that is distinguished by a minimal level of star formation activity. With our new (CO)-C-12(J = 2-1) and (CO)-C-13(J = 2-1) observations of a remote region within the middle of the California molecular cloud, we aim to investigate the relationship between filaments, cores, and a molecular outflow in a relatively pristine environment. An extinction map of the region from Herschel Space Observatory observations reveals the presence of two 2 pc long filaments radiating from a highextinction clump. Using the (CO)-C-13 observations, we show that the filaments have coherent velocity gradients and that their mass-per-unit-lengths may exceed the critical value above which filaments are gravitationally unstable. The region exhibits structure with eight cores, at least one of which is a starless, prestellar core. We identify a low-velocity, low-mass molecular outflow that may be driven by a flat spectrum protostar. The outflow does not appear to be responsible for driving the turbulence in the core with which it is associated, nor does it provide significant support against gravitational collapse.
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Tajudeen, Mohammed Ashiq Rahman. "GENERAL WAKE-UP RADIO MODULE FOR ISM BAND." Thesis, Högskolan i Halmstad, Akademin för informationsteknologi, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-36378.
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With the word of smart, the whole world is running on the smart technologies and smart devices which are fairly constructed by wireless sensors networks. The heart of the WSNs are nodes, which are deployed in different environmental conditions with different applications.‘Power constraint’ is a major challenge faced by all manufacturers of nodes, as all the components of the nodes are running just with a single source battery.The work presented in this thesis is an attempt to reduce the power consumption of WSNsby developing a unique Wake-Up Radio system that is super-efficient in power consumption when one compares it to duty cycling method. This paper presents a simple wake-up radio architecture with easily available Off the shelf components and operating in ISM band.At the transmitting end, a receiver with 125 KHz baseband signal is modulated on an 868MHz frequency carrier and is transmitted with the help of homemade dipole antenna. The wake-up radio receiver is constructed with a receiving antenna of 868 MHz and a network that matches good impedance to reduce the power loss of received signal, followed by a demodulation circuit with HSMS-285C zero bias Schottky diode to retrieve the baseband signal and to increase the sensitivity of the device. Later, the retrieved baseband signal is received by AS3933 low frequency wake-up receiver. The AS933 works like a comparator which compares the incoming address with the stored address to generate wake-up interrupt over node’s microcontroller activating it to perform its function.Measurements were made with the help of AS3933 demo board. The proposed system has a current consumption of 42.74μA including the current consumption of the components deployed in the demo board. In an ideal case, wake-up radio can be constructed without usingAS3933 demo board by using only AS3933 IC that gives current consumption of 2.8μA. The developed prototype has a sensitivity of -40 dBm which resulted in a wake-up distance of 20meters at an output power of -5 dBm from the transmitting antenna. This justifies that the proposed system lowers power consumption in wireless sensor networks when compared to duty cycling.
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Clark, David John. "ISM band systems : power consumption, usability and economics." Thesis, Durham University, 2011. http://etheses.dur.ac.uk/3267/.
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This thesis describes research into a specific area of Industrial Scientific and Medical (ISM) band applications that employ a central control panel to send broadcast information to the units in a system. One example of this is fire safety systems. The focus is on how battery life, reliability and usability of such a system may be improved through different mechanisms. The case study application is a system of radio controlled fire door holders. Following a review of the current literature and a look at the considerations of designing a wireless network, a comparison is made of two radio transceivers, each of which operates in a different frequency band. Testing is performed with both, and a choice made as to which to use in system implementations and further research. Results from the first system implementation quantify communications and circuitry improvements that increase battery life through improved receiver sensitivity and communications resilience. The second system implements a narrowband system, as well as improving unit displays for information output and system troubleshooting. Results from it show a further increase in receiver sensitivity and techniques developed to improve timing to reduce on-time, so reducing power consumption further. The third implementation employs frequency hopping techniques along with further advances in timing. Enhanced display manager techniques add to the usability of the system. Beyond this, more recent chip technology is used with algorithmic changes in small test units to assess how further improvements can be made in terms of battery life. A ten-fold improvement in battery life compared to the original implementation is shown to be possible when comparing the narrowband and wideband systems. Further improvements are described employing the latest chip technology.
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Viana, Maurício Boratto. "Avaliando Minas : índice de sustentabilidade da mineração (ISM)." reponame:Repositório Institucional da UnB, 2012. http://repositorio.unb.br/handle/10482/10542.
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Tese (doutorado)—Universidade de Brasília, Centro de Desenvolvimento Sustentável, 2012.Submitted by Albânia Cézar de Melo (albania@bce.unb.br) on 2012-05-22T15:05:20Z No. of bitstreams: 1 2012_MauricioBorattoViana.pdf: 9928570 bytes, checksum: f40b0bec7e23345ee9f352ae113075de (MD5)
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Esta tese de Doutorado tem por objeto de estudo um sistema de avaliação para a construção do Índice de Sustentabilidade da Mineração (ISM), a partir da proposição e agregação de indicadores nas dimensões econômica, social e ambiental e sua aferição em unidades operacionais minerárias selecionadas, incluindo as comunidades existentes em seu entorno e o município em que elas se inserem. Como marco referencial, são analisadas questões afetas ao desenvolvimento sustentável e seus indicadores, bem como à mineração sustentável e às iniciativas de proposição de indicadores para o setor. Já as atividades centrais consistiram na submissão de uma lista de setenta indicadores a 165 especialistas, na aferição desses indicadores em uma dezena de minerações situadas no Estado de Minas Gerais e na aplicação de 450 questionários nas comunidades de entorno, seguidas de uma detalhada análise, incluindo simulações, dos dados coletados. Como se sabe, a mineração é dotada de certas peculiaridades: rigidez locacional, exaustão mineral, impacto socioambiental, controle internacional de preços e longo prazo de maturação. Assim, sua sustentabilidade não pode ser avaliada só pela simples continuidade das atividades anos afora e, muito menos, tomar por base apenas as ações efetuadas intramuros. Para ser considerada sustentável, ela deve minimizar seus impactos negativos, compensar os não-mitigáveis e, simultaneamente, promover o bem-estar das comunidades envolvidas. Além disso, as rendas que ela produz na atualidade devem ensejar novas opções econômicas locais após a exaustão da jazida. A importância desta tese reside no fato de se tratar de iniciativa inovadora, que propõe a avaliação da sustentabilidade da mineração com base em dezenas de indicadores, aferidos, cada qual, por meio de escala específica, mas variável dentro de limites prefixados, que proporcionam a agregação final dos indicadores em três índices dimensionais e no ISM. Trata-se, talvez, da primeira proposta para o setor minerário que leva em conta, nessa avaliação, a opinião das comunidades afetadas, bem como a eventual influência da mineração no município em que está inserida, dando vez e voz ao sentido mais amplo da sustentabilidade. ______________________________________________________________________________ ABSTRACT
This PhD dissertation consists of an assessment system used to build the Mining Sustainability Index (MSI), based on the proposition and aggregation of indicators in economic, social and environmental dimensions and its assessment in selected mining operational units, including the communities located in their immediate surroundings and the municipalities in which they are inserted. As referential framework, themes related to sustainable development and its indicators are analyzed, in addition to those related to sustainable mining and the initiatives that propose indicators for the sector. Main surveys consisted of submitting a seventy-indicator list to 165 specialists, measuring these indicators in ten mining operation units located in the State of Minas Gerais, and applying 450 questionnaires to communities located in the immediate surroundings of the mines, followed by a detailed analysis including simulations of the collected data. As is well known, mining activities have certain peculiarities: geologically fixed deposits, mineral depletion, social environmental impact, international control of prices and long-term investment. Thus, sustainability cannot be assessed by the simple endurance of activities throughout the years or based only on internal actions. To be considered sustainable, mining must reduce its negative impacts, compensate the non-reducible ones and, at the same time, promote the well-being of the communities involved. Additionally, revenues currently generated must give cause to new local economic activities in the period after the deposit depletion. The importance of this dissertation is its innovative initiative that proposes a mining sustainability assessment on the basis of dozens of indicators, each one measured according to specific scales, variable within prefixed limits, providing, in the end, the aggregation of indicators in three dimension indexes and in the MSI. It might be the first proposal for the mining sector that takes into account the affected communities’ opinion in the assessment, as well as the possible influence of the mining operation in the municipality in which it is inserted, providing voice and opportunity to the wider concept of sustainability.
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Norris, Joshua J. ""ISM" analysis a necessity for effective strategic communication /." Thesis, Monterey, Calif. : Naval Postgraduate School, 2008. http://edocs.nps.edu/npspubs/scholarly/theses/2008/Sept/08Sep%5FNorris.pdf.
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Thesis (M.S. in Information Warfare Systems Engineering)--Naval Postgraduate School, September 2008.Thesis Advisor(s): Iatrou, Steven. "September 2008." Description based on title screen as viewed on October 31, 2008. Includes bibliographical references (p. 57-58). Also available in print.
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Foight, Dillon R., Tolga Güver, Feryal Özel, and Patrick O. Slane. "PROBING X-RAY ABSORPTION AND OPTICAL EXTINCTION IN THE INTERSTELLAR MEDIUM USING CHANDRA OBSERVATIONS OF SUPERNOVA REMNANTS." IOP PUBLISHING LTD, 2016. http://hdl.handle.net/10150/621375.
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We present a comprehensive study of interstellar X-ray extinction using the extensive Chandra supernova remnant (SNR) archive and use our results to refine the empirical relation between the hydrogen column density and optical extinction. In our analysis, we make use of the large, uniform data sample to assess various systematic uncertainties in the measurement of the interstellar X-ray absorption. Specifically, we address systematic uncertainties that originate from (i) the emission models used to fit SNR spectra; (ii) the spatial variations within individual remnants; (iii) the physical conditions of the remnant such as composition, temperature, and non-equilibrium regions; and (iv) the model used for the absorption of X-rays in the interstellar medium. Using a Bayesian framework to quantify these systematic uncertainties, and combining the resulting hydrogen column density measurements with the measurements of optical extinction toward the same remnants, we find the empirical relation N-H = (2.87 +/- 0.12) x 10(21) A(V) cm(-2), which is significantly higher than the previous measurements.
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Seo, Young Min, and Andrew N. Youdin. "The role of non-ionizing radiation pressure in star formation: the stability of cores and filaments." OXFORD UNIV PRESS, 2016. http://hdl.handle.net/10150/621725.
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Stars form when filaments and dense cores in molecular clouds fragment and collapse due to self-gravity. In the most basic analyses of gravitational stability, the competition between self-gravity and thermal pressure sets the critical (i.e. maximum stable) mass of spheres and the critical line density of cylinders. Previous work has considered additional support from magnetic fields and turbulence. Here, we consider the effects of non-ionizing radiation, specifically the inward radiation pressure force that acts on dense structures embedded in an isotropic radiation field. Using hydrostatic, isothermal models, we find that irradiation lowers the critical mass and line density for gravitational collapse, and can thus act as a trigger for star formation. For structures with moderate central densities, similar to 10(3) cm(-3), the interstellar radiation field in the Solar vicinity has an order unity effect on stability thresholds. For more evolved objects with higher central densities, a significant lowering of stability thresholds requires stronger irradiation, as can be found closer to the Galactic centre or near stellar associations. Even when strong sources of ionizing radiation are absent or extincted, our study shows that interstellar irradiation can significantly influence the star formation process.
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Barnes, Peter J., Audra K. Hernandez, Stefan N. O’Dougherty, III William J. Schap, and Erik Muller. "THE GALACTIC CENSUS OF HIGH- AND MEDIUM-MASS PROTOSTARS. III. 12 CO MAPS AND PHYSICAL PROPERTIES OF DENSE CLUMP ENVELOPES AND THEIR EMBEDDING GMCs." IOP PUBLISHING LTD, 2016. http://hdl.handle.net/10150/622167.
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We report the second complete molecular line data release from the Census of High-and Medium-mass Protostars (CHaMP), a large-scale, unbiased, uniform mapping survey at sub-parsec resolution, of millimeter-wave line emission from 303 massive, dense molecular clumps in the Milky Way. This release is for all (CO)-C-12 J = 1 -> 0 emission associated with the dense gas, the first from Phase II of the survey, which includes (CO)-C-12, (CO)-C-13, and (CO)-O-18. The observed clump emission traced by both (CO)-C-12 and HCO+ (from Phase I) shows very similar morphology, indicating that, for dense molecular clouds and complexes of all sizes, parsec-scale clumps contain. similar to 75% of the mass, while only 25% of the mass lies in extended (>10 pc) or "low density" components in these same areas. The mass fraction of all gas above a density of 10(9) m(-3) is xi(9) greater than or similar to 50%. This suggests that parsec-scale clumps may be the basic building blocks of the molecular interstellar medium, rather than the standard GMC concept. Using (CO)-C-12 emission, we derive physical properties of these clumps in their entirety, and compare them to properties from HCO+, tracing their denser interiors. We compare the standard X-factor converting I (CO)-C-12 to N-H2 with alternative conversions, and show that only the latter give whole-clump properties that are physically consistent with those of their interiors. We infer that the clump population is systematically closer to virial equilibrium than when considering only their interiors, with perhaps half being long-lived (10s of Myr), pressure-confined entities that only terminally engage in vigorous massive star formation, supporting other evidence along these lines that was previously published.
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Schirm, M. R. P., C. D. Wilson, J. Kamenetzky, T. J. Parkin, J. Glenn, P. Maloney, N. Rangwala, et al. "Probing the cold and warm molecular gas in the Whirlpool Galaxy: Herschel SPIRE-FTS observations of the central region of M51 (NGC 5194)." OXFORD UNIV PRESS, 2017. http://hdl.handle.net/10150/625734.
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We present Herschel Spectral and Photometric Imaging Receiver (SPIRE)-Fourier Transform Spectrometer (FTS) intermediate-sampled mapping observations of the central similar to 8 kpc (similar to 150 arcsec) of M51, with a spatial resolution of 40 arcsec. We detect four (CO)-C-12 transitions (J = 4-3 to J = 7-6) and the [C i] P-3(2)-P-3(1) and P-3(1)-P-3(0) transitions. We supplement these observations with ground-based observations of (CO)-C-12 J = 1-0 to J = 3-2 and perform a two-component non-local thermodynamic equilibrium analysis. We find that the molecular gas in the nucleus and centre regions has a cool component (T-kin similar to 10-20 K) with a moderate but poorly constrained density (n(H-2) similar to 10(3)-10(6) cm(-3)), as well as significant molecular gas in a warmer (T-kin similar to 300-3000 K), lower density (n(H-2) similar to 10(1.6)-10(2.5) cm(-3)) component. We compare our CO line ratios and calculated densities along with ratios of CO to total infrared luminosity to a grid of photon-dominated region (PDR) models and find that the cold molecular gas likely resides in PDRs with a field strength of G(0) similar to 10(2). The warm component likely requires an additional source of mechanical heating, from supernovae and stellar winds or possibly shocks produced in the strong spiral density wave. When compared to similar two-component models of other star-forming galaxies published as part of the Very Nearby Galaxies Survey (Arp 220, M82 and NGC 4038/39), M51 has the lowest density for the warm component, while having a warm gas mass fraction that is comparable to those of Arp 220 and M82, and significantly higher than that of NGC 4038/39.
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Stanimirovic, Snezana, University of Western Sydney, and Centre for Astronomy. "The complex nature of the ISM in the SMC." THESIS_XXXX_CFA_Stanimirovic_S.xml, 1999. http://handle.uws.edu.au:8081/1959.7/516.
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This thesis presents the results of a combination of new observations with the Parkes telescope of neutral hydrogen (HI) in the Small Magellanic Cloud (SMC) with an Australia Telescope Compact Array aperture synthesis mosaic. The data are used to study the HI distribution and mass, the velocity field and rotation curve of the SMC, as well as to probe the 3-D structure of the SMC. A kinematic study of the HI data reveals the existence of three supergiant shells which were previously undetectable in the ATCA data alone. The HI spatial power spectrum has been investigated over a range of contiguous scale sizes wider than those previously achieved in any other galaxy. This thesis also demonstrates that the infrared data obtained with the Infrared Astronomical Satellite for the SMC can be successfully reconstructed with much higher resolution using the Pyramid Maximum Entropy algorithm. The new infrared (IR) data are used to study the integrated IR spectrum, the dust temperature and dust column density in the SMC. The high resolution HI and IR data enable an investigation of the spatial correlation of dust and gas and the assumption of the dust and gas being well-mixed in the ISM. The spatial power spectrum of the dust column density shows that, as with the HI power spectrum, there is no preferred scale size for dust clouds. The remarkable similarity of the spatial power spectra for the HI and dust column density distributions suggests a unique hierarchical structure organisation for the ISM in the SMC. Such an organisation is likely to be governed by the Kolmogorov type turbulence and could be described by fractal nature with the volume fractal dimension of 2.4.Doctor of Philosophy (PhD)
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Millot, Anthony. "Etude d'un réseau de capteurs environnementaux en bande ISM." Phd thesis, Université d'Orléans, 2010. http://tel.archives-ouvertes.fr/tel-00573695.
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Cette thèse présente l'étude d'un réseau de capteurs pour la surveillance en temps réel de la qualité des eaux souterraines. L'objectif est de réussir à communiquer dans la bande de fréquences libre à 433MHz sur plusieurs dizaines de kilomètres. Le problème majeur des bandes libres est la présence de transmissions parasites (brouilleurs). Nous avons donc, en premier lieu, mis en évidence de la présence de ces brouilleurs et étudier leur impact sur les communications. Après analyse, il s'avère que les brouilleurs sont très nombreux et puissants mais que leur répartition dans la bande est inégale. Une étude spectrale de la bande semble nécessaire, avant la mise en place du réseau, afin de transmettre dans les canaux les moins pollués. Des communications nocturnes sont également à privilégier car les brouilleurs sont moins nombreux la nuit. Nous présentons ensuite une architecture réseau, adaptée au cahier des charges et à cette bande de fréquences. Nous avons également testé un composant RF dédié aux transmissions en bande ISM. Les résultats montrent que les performances de ce composant sont faibles pour des communications longues distances en présence de brouilleurs. Un récepteur radiofréquence simple ne permet donc pas de réaliser des communications fiables dans ces conditions. Le prototype complet du réseau, développé durant ces travaux, est ensuite décrit. Pour finir, nous proposons un nouveau concept de récepteur, utilisant un réseau d'antennes phasé et un détecteur cyclostationnaire, pour pallier au problème des brouilleurs. Le but est de stocker les signaux reçus pour les traiter en temps différé à l'aide d'algorithmes de filtrage spatial. Des simulations montrent l'efficacité de ce concept.
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Cordiner, Martin. "Diffuse interstellar bands and the structure of the ISM." Thesis, University of Nottingham, 2005. http://eprints.nottingham.ac.uk/11952/.
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This may be interpreted as evidence that the profile of sub-structure of the lambda 6614 DIB is skewed towards the red in these three sightlines (Sk -68°135, Sk -69°223 and Sk -69°243) to a greater degree than that found in the Galactic ISM. Compared to Galactic trends, the LMC DIBs are found to be weak with respect to the reddening and neutral potassium column density towards Sk -67°2 and Sk -68°135. This may be attributable to a combination of the high UV flux and reduced shielding of interstellar clouds due to the low metallicity of the interstellar gas of the LMC, and results in the destruction of DIB carriers by photodissociation and/or photoionisation. Relative to N(H I) the lambda 6284 DIB observed in four LMC sightlines is shown to be approximately 1/5 to 1/2 of its average strength in the Milky Way. This supports the idea that the metallicity and/or dust-to-gas ratio of the ISM is closely linked with the chemistry that governs the abundance of DIB carriers relative to N(H I). Variations in the N(Ca II)/N(Ti II) ratio are found over at least an order of magnitude in the LMC ISM, and are taken as evidence for significant variation in the Ca n/Ca m ionisation balance. Derived logarithmic titanium depletions are found to be relatively low in the six LMC sightlines studied, with values between approximately -0.8 and -1.9, which are similar to the levels of depletion generally seen in the warm, shocked interstellar medium of the Galaxy.
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Price, Richard John. "Ultra-high-resolution spectroscopy of the ISM towards Orion." Thesis, University College London (University of London), 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.252156.
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Scheiner, Benedict [Verfasser]. "Miniaturisiertes sechstorbasiertes Frequenzmesssystem für berührungslose ISM-Anwendungen / Benedict Scheiner." München : Verlag Dr. Hut, 2021. http://nbn-resolving.de/urn:nbn:de:101:1-2021100123323695444626.
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Hedden, Abigail S. "Exploring Life-Cycles of the ISM at Submillimeter Wavelengths." Diss., The University of Arizona, 2007. http://hdl.handle.net/10150/196018.
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This thesis focuses on addressing some important aspects of the life cycle of interstellar clouds through observational submillimeter and millimeter-wave studies of star formation and molecular cloud environments and the development of instrumentation to enable these studies.We examine the influence of star formation on parent molecular clouds through a case study of protostellar sources in the Mon OB1 northern cloud complex. An energetics analysis of these star forming regions and associated molecular outflows was carried out, suggesting that the cloud complex maintains its overall integrity, except along outflow axes and that the coupling between outflow kinetic energy and cloud turbulent energy is weak, < ~0.5%. In order to study the larger picture of cloud formation and disruption, this work was expanded to explore the molecular environment at cloud boundaries. To this end, acloud edge survey was undertaken consisting of multi-transition strip scan observations of CO and 13CO toward molecular clouds with a broad range of stellar and star forming characteristics. Our work supports the interpretation that cloud formation is taking place along the southeastern edge of Heiles Cloud 2, and the results will be used as a framework for guiding the analysis of other surveyed cloud edges.Achieving observational capabilities enabling effective studies of life cycles of the ISM is becoming possible through a new generation of heterodyne spectroscopic instruments. Here, we report on characterization measurements of a prototype mixer unit for the 64-pixel SuperCam array, an instrument commissioned to mapover 500 square degrees of the Galactic Plane with very high resolution at 345 GHz. These measurements were crucial to verifying the overall array design and anticipating its performance. Spectroscopic capabilities at THz (< 300 microns) frequencies permits access to a host of diagnostic tools (e.g., high-J CO, CI, NII, & CII) uniquely suited to probe crucial properties of the ISM. The development of heterodynetechnology at these frequencies is largely limited by availability of compact, powerful sources of local oscillator power. We explore the use of waveguide spatial filters in conjunction with Quantum Cascade Lasers, a promising power source at frequenciesabove ~ 2 THz.
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Berger, Kelly Marie. "Face-ism and the Effects of Facial Prominence Manipulation." Thesis, The University of Arizona, 2013. http://hdl.handle.net/10150/297512.
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Previous research has found that the media tends to portray men in terms of their faces and women in terms of their bodies. The measure of this face to body ratio is called facial prominence, or face-ism. High face-ism has been associated with higher perceptions of positive attributes. In this study, online survey participants were asked to help design a prestigious company’s print advertisement. Participants were shown three different stimulus persons, each in a high face-ism condition and a low face-ism condition, and were asked to choose which image of the person best portrayed dominance, intelligence, attractiveness, and ambition. Surprisingly, participants more frequently chose the low face-ism images of the stimuli to represent these traits. Participants showed preference for male stimuli with high facial prominence and preference for female stimuli with low facial prominence. No significant relationship was found between participants’ amount of daily media consumption and facial prominence preference. No significant relationship was found between facial prominence of the stimuli and participants’ ability to remember detail about the stimuli. Further research is warranted because facial prominence manipulation has many potential effects and the existing research on the topic is inconsistent.
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Camargo-Pardo, Javier-Andrés. "Systèmes injectables biodégradables pour la libération prolongée d'ivermectine." Thesis, Nancy 1, 2010. http://www.theses.fr/2010NAN10068/document.
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Des systèmes injectables de formation in situ ont été utilisés dans les dernières années pour l'obtention de formulations de préparation facile et permettant la libération prolongée de principes actifs. Ces systèmes utilisant des solvants biocompatibles et des polymères biodégradables sont des liquides (solutions ou émulsions) qui une fois injectés dans l'organisme donnent lieu à des implants (ISI) ou à des microparticules (ISM) solides. La formation de ces systèmes est induite par la précipitation du polymère à partir des solutions polymériques qu'ils contiennent lors du contact avec les fluides corporaux aqueux. Dans ce travail, des ISI et des ISM, réalisés à partir des polymères de l'acide lactique et/ou glycolique (PLA et PLGA) et des différents solvants biocompatibles, pour la libération prolongée d?ivermectine (IVM), un principe actif antiparasitaire faiblement biodisponible par la voie orale, ont été développés. Les profils de libération du principe actif in vitro et in vivo à partir de ces systèmes, ont été comparés avec ceux obtenus à partir de microparticules réalisées par la méthode classique dite d'émulsion simple - évaporation de solvant ; il s'agit d'une technique aux multiples étapes, à coût élevé et dont l'utilisation de solvants toxiques la font difficilement industrialisable. La libération du principe actif à partir des microparticules obtenues par émulsion simple/évaporation du solvant a été influencée par la forte interaction du principe actif avec les polymères mais aussi par la porosité. Dans le cas des systèmes in situ, la vitesse de libération d'IVM a été conditionnée par la solubilité dans l'eau du solvant biocompatible sélectionné et par les interactions solvant/polymère. Pour les ISM, des paramètres tels que la nature de la phase externe, aqueuse (ISM-O/W) ou huileuse (ISM-O/O), la solubilité dans l'eau du solvant de la phase interne, l'affinité entre les phases et l'affinité de l'IVM pour chacune des phases, ont déterminé la vitesse de libération du principe actif. La bonne stabilité ainsi que les profils de libération plus prolongés et présentant une faible libération initiale du principe actif in vivo et in vitro, ont montré que les ISI et les ISM réalisés à partir de solvants biocompatibles de faible solubilité dans l'eau tels que la triacetine sont les plus indiqués pour l'encapsulation d'IVM par rapport à ceux plus solubles dans l'eau comme la N-methyl-2-pyrrolidone et la 2-pyrrolidone. Ces systèmes représentent donc une alternative intéressante par rapport aux formulations conventionnelles d'IVMIn situ forming injectable systems have been used in the past years to obtain sustained drug release formulations which are easy to prepare. These systems using biocompatible solvents and biodegradable polymers are liquids (solutions or emulsions) that upon injection on the body lead to solid implants (ISI) or microparticles (ISM). These systems are formed in contact with water body fluids by polymer precipitation from the polymeric solution. In this work, ISI and ISM made from lactide and/or glycolide polymers (PLA and PLGA) and different biocompatible solvents were performed to obtain sustained release of ivermectin (IVM), an antiparasitic drug with a low oral bioavailability. In vitro and in vivo drug release profiles from these systems were compared with those from microparticles obtained by the classical simple emulsion/solvent evaporation method, which is difficult to propose in industry because of its multiple steps, high cost and the solvent toxicity. Drug release from simple emulsion/solvent evaporation microparticles was affected by the strong polymer/drug interactions and porosity. Concerning to in situ forming systems, the rate of IVM release was dependent on solvent water solubility and solvent/polymer interactions. The nature of the external phase, water (ISM-O/W) or oil (ISM-O/O), the water solubility of the solvent in the internal phase, phase affinity and IVM/phase affinity determined drug release from ISM. The good stability, the in vitro and in vivo sustained release and the low burst effect of IVM, indicated that ISI and ISM formulated from low hydrosoluble biocompatible solvents such as triacetin are more appropriated to IVM formulation instead of those based on more hydrophilic solvent (N-methyl-2-pyrrolidone and 2-pyrrolidone). These systems are an interesting alternative to conventional IVM formulations
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Schmidt, D. R., and L. M. Ziurys. "New Identifications of the CCH Radical in Planetary Nebulae: A Connection to C-60?" IOP PUBLISHING LTD, 2017. http://hdl.handle.net/10150/626258.
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New detections of CCH have been made toward nine planetary nebulae (PNe), including K4-47, K3-58, K3-17, M3-28, and M4-14. Measurements of the N = 1 -> 0 and N = 3 -> 2 transitions of this radical near 87 and 262 GHz were carried out using the new 12 m and the Sub-Millimeter Telescope (SMT) of the Arizona Radio Observatory (ARO). The presence of fine and/or hyperfine structure in the spectra aided in the identification. CCH was not observed in two PNe which are sources of C-60. The planetary nebulae with positive detections represent a wide range of ages and morphologies, and all had previously been observed in HCN and HNC. Column densities for CCH in the PNe, determined from radiative transfer modeling, were N-tot(CCH) similar to 0.2-3.3 x 10(15) cm(-2), corresponding to fractional abundances with respect to H-2 of f similar to 0.2-47 x 10(-7). The abundance of CCH was found to not vary significantly with kinematic age across a time span of similar to 10,000 years, in contrast to predictions of chemical models. CCH appears to be a fairly common constituent of PNe that are carbon-rich, and its distribution may anti-correlate with that of C-60. These results suggest that CCH may be a product of C-60 photodestruction, which is known to create C-2 units. The molecule may subsequently survive the PN stage and populate diffuse clouds. The distinct, double-horned line profiles for CCH observed in K3-45 and M3-28 indicate the possible presence of a bipolar flow oriented at least partially toward the line of sight.
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Schmidt, D. R., and L. M. Ziurys. "NEW DETECTIONS OF HNC IN PLANETARY NEBULAE: EVOLUTION OF THE [HCN]/[HNC] RATIO." IOP PUBLISHING LTD, 2017. http://hdl.handle.net/10150/622874.
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New detections of HNC have been made toward 11 planetary nebulae (PNe), including K4-47, K3-58, K3-17, M3-28, and M4-14. These sources, which represent a wide range of ages and morphologies, had previously been observed in HCN by Schmidt & Ziurys. Measurements of the J = 1 -> 0 and J = 3 -> 2 transitions of HNC near 90 and 271 GHz were conducted using the new 12 m and the Sub-Millimeter Telescope of the Arizona Radio Observatory. HCN and HNC were also identified via their J = 1 -> 0 lines toward eight positions across the Helix Nebula (NGC 7293). Column densities for HNC, determined from radiative transfer modeling, were N-tot(HNC) similar to (0.06-4.0) x 10(13) cm(-2), corresponding to fractional abundances with respect to H-2 of f similar to (0.02-1.4) x 10(-7). The HCN and HNC column densities across the Helix were found to be N-tot (HCN) similar to (0.2-2.4). x. 10(12) cm(-2) and Ntot (HNC) similar to (0.07-1.6). x. 1012 cm(-2), with fractional abundances of (0.2-3.2) x 10(-7) and (0.09-2.2) x 10(-7). The [ HCN]/[ HNC] ratio varied between similar to 1-8 for all PNe, with [ HCN]/[ HNC] similar to 1-4 across the Helix. These values are greatly reduced from what has been found in asymptotic giant branch stars, where the ratio is typically > 100. Both the abundance of HNC and the [ HCN]/[ HNC] ratio do not appear to vary significantly with nebular age across a time span of similar to 10,000 years, in contrast to predictions of chemical models. The increase in HNC appears to arise in the proto-planetary stage, but becomes " frozen" once the PN phase is reached.
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Klíma, Jan. "Bezdrátové komunikační moduly pro mikrokontroléry." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2011. http://www.nusl.cz/ntk/nusl-219328.
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The aim of this master’s thesis is analysis of wireless communication between mikroprocesors. The first part of the work are analysed the problems the wireless free ISM band. Mainly RFM12B and ZigBee module, which i these band work and ZigBee standart. The second part are described relazation board for both module. Further how programming ZigBee module. And at last programs for tested module.
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Tavakoli, Hosseinabadi Ahmad Reza. "Fully integrated cmos phase shifter/vco for mimo/ism application." [College Station, Tex. : Texas A&M University, 2007. http://hdl.handle.net/1969.1/ETD-TAMU-2502.
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Sartorio, Kleber [UNESP]. "Uma ferramenta para captura de ontologias baseada na técnica ISM." Universidade Estadual Paulista (UNESP), 2004. http://hdl.handle.net/11449/90814.
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Embora a representação do conhecimento por meio de ontologias tenha evoluído muito nos últimos anos, seus benefícios são usufruídos por um número ainda restrito de organizações. A fim de possibilitar que a aplicação de ontologias seja uma alternativa ao alcance de todas as organizações, é preciso simplificar a apresentação do conceito de ontologias, explicitando suas utilidades e fornecendo meios que facilitem sua construção. Com o objetivo de contribuir para o atendimento dessas necessidades, este trabalho se propõe a realizar duas tarefas: o levantamento das metodologias existentes para a criação de ontologias, quando será observado como é processada a fase de captura; e a adaptação...
Knowledge representation by means of ontology has gained great attention. Even thought, a restrict number of organizations takes advantage of using ontologies. In order to extend ontologies use, its's necessary to simplify the presentation of its concepts, make clear its usefulness and provide tools that facilitate its construction. As a contribution for these purposes, the objective of this work is to present a tool for capturing ontologies based on Interpretative Structural Modeling (ISM) and addressed to non-specialists on ontologies. ISM is a well known technique; good at helping the understanding of complex problem as well as at provide a framework for establishing the main among concepts. Such tool will help and guide... (Complete abstract click electronic access below)
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Loo, Sek Yuen. "Design and implementation of an ISM-band PLL frequency synthesizer." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0029/MQ65503.pdf.
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Sydsjö, Norlin Karin. "A legal review of the International Safety Management (ISM) code /." Stockholm : Swedish Maritime Law Assoc, 1998. http://www.gbv.de/dms/spk/sbb/recht/toc/371956676.pdf.
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Mendoza, Garcia Marylena. "The ISM code : a reexamination of certain Maritime law principles." Thesis, McGill University, 2001. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=32812.
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Maritime Safety is one of the most important issues dealt with by the International Maritime Organization (IMO). With the aim at improving maritime safety and pollution prevention, in 1994 SOLAS 1974 was amended and Chapter IX entitled "Management for the Safe Operation of Ships" was added, giving in this way existence to the International Safety Management Code. This amendment took place through the tacit acceptance procedure implemented by IMO, thus it has a mandatory character for SOLAS Contracting States. The Code was established to have effect in two stages, the first stage took place on July 1 1998, and the second stage will take place on July 1 2002.The ISM Code establishes requirements, which, although not completely new to the maritime industry, will have great incidence in the way maritime activities are carried out to date. Shipping Companies will suffer alterations on their management structure and certain principles in maritime law will probably be changed with the introduction of the Code, however, the precise effects of the ISM Code cannot be outlined before its full implementation takes place in 2002.
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Mann, Sebastian [Verfasser]. "Sechstor-Radarsysteme für den Einsatz in ISM-Anwendungen / Sebastian Mann." München : Verlag Dr. Hut, 2019. http://d-nb.info/1200755340/34.
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Sartorio, Kleber. "Uma ferramenta para captura de ontologias baseada na técnica ISM /." Bauru : [s.n.], 2004. http://hdl.handle.net/11449/90814.
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Orientador: José Eduardo Cogo CastanhoBanca: Márcio Rillo
Banca: Marcelo Nicoletti Franchin
Resumo: Embora a representação do conhecimento por meio de ontologias tenha evoluído muito nos últimos anos, seus benefícios são usufruídos por um número ainda restrito de organizações. A fim de possibilitar que a aplicação de ontologias seja uma alternativa ao alcance de todas as organizações, é preciso simplificar a apresentação do conceito de ontologias, explicitando suas utilidades e fornecendo meios que facilitem sua construção. Com o objetivo de contribuir para o atendimento dessas necessidades, este trabalho se propõe a realizar duas tarefas: o levantamento das metodologias existentes para a criação de ontologias, quando será observado como é processada a fase de captura; e a adaptação... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Knowledge representation by means of ontology has gained great attention. Even thought, a restrict number of organizations takes advantage of using ontologies. In order to extend ontologies use, its's necessary to simplify the presentation of its concepts, make clear its usefulness and provide tools that facilitate its construction. As a contribution for these purposes, the objective of this work is to present a tool for capturing ontologies based on Interpretative Structural Modeling (ISM) and addressed to non-specialists on ontologies. ISM is a well known technique; good at helping the understanding of complex problem as well as at provide a framework for establishing the main among concepts. Such tool will help and guide... (Complete abstract click electronic access below)
Mestre
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Potočňak, Martin. "Koexistence systémů LTE a LoRa v ISM pásmu 2.4 GHz." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2019. http://www.nusl.cz/ntk/nusl-400546.
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This diploma thesis deals with the study and measurement of coexistence scenarios that can occur between the LTE and LoRa systems in the unlicensed ISM band 2.4 GHz. A common radio frequency band in which LTE and LoRa systems can coexist is defined. An appropriate laboratory measurement is proposed and realized, allowing automatized measurement of the defined coexistence scenarios. For this purpose, a personal computer, professional measurement equipment and software MATLAB are utilized. Functionality of the proposed concept is verified by extensive measurements. The obtained results are graphically shown and discussed in detail.
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Salvestrini, Francesco <1991>. "The impact of AGN activity on the host-galaxy ISM." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2021. http://amsdottorato.unibo.it/9830/3/salvestrini_phd_thesis.pdf.
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In this Thesis I investigate how, and to which extent, Active Galactic Nuclei (AGN) activity affects the properties of the host-galaxy interstellar medium (ISM). AGN are thought to regulate the host star formation (SF) by injecting large amount of energy in the circumnuclear region, either suppressing or enhancing the formation of new stars. To understand the interplay between AGN and SF multi-wavelength approach is needed, which allows us to trace the different gas components.
In the first part of the Thesis, I present the result of a systematic analysis of the X-ray properties of a sample of local Seyfert 2 galaxies (Gruppioni et al. 2016), necessary to characterise the AGN activity to unveil its intrinsic power. To investigate the properties of the dusty torus in different bands, I compare the level of obscuration estimated from the X-ray spectral analysis, with the one derived from the strength of the 9.7μm silicate feature in the mid-IR.
In the second part of the Thesis, I determine the molecular gas content of the same sample of Seyfert 2 galaxies by using single-dish observations tracing the CO emission line. By comparing our results with a control sample of inactive galaxies, I observe that AGN do not differentiate from star-forming galaxies (SFGs) in terms of molecular gas content and corresponding depletion time. I also assess the influence of AGN on the emission of SF tracers in the mid-IR features.
Finally, I provide a complete and coherent multi-wavelength characterisation on a test case galaxy, NGC 7213, drawn from the same parent sample. This target came out to be of particular interest because of the kinematical modelling on ALMA data, which reveals the presence of two molecular outflows. I complement the analysis with a detailed X-ray spectral analysis to determine the AGN accretion power.
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Shi, Yong, Lin Yan, Lee Armus, Qiusheng Gu, George Helou, Keping Qiu, Stephen Gwyn, et al. "Revisiting the Extended Schmidt Law: The Important Role of Existing Stars in Regulating Star Formation." IOP PUBLISHING LTD, 2018. http://hdl.handle.net/10150/627041.
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We revisit the proposed extended Schmidt law, which posits that the star formation efficiency in galaxies depends on the stellar mass surface density, by investigating spatially resolved star formation rates (SFRs), gas masses, and stellar masses of star formation regions in a vast range of galactic environments, from the outer disks of dwarf galaxies, to spiral disks and to merging galaxies, as well as individual molecular clouds in M33. We find that these regions are distributed in a tight power law as Sigma(SFR) proportional to (Sigma(0.5)(star)Sigma(gas))(1.09), which is also valid for the integrated measurements of disk and merging galaxies at high-z. Interestingly, we show that star formation regions in the outer disks of dwarf galaxies with Sigma(SFR) down to 10(-5) M(circle dot)yr(-1) kpc(-2), which are outliers of both the Kennicutt-Schmidt and Silk-Elmegreen laws, also follow the extended Schmidt law. Other outliers in the Kennicutt-Schmidt law, such as extremely metal-poor star formation regions, also show significantly reduced deviation from the extended Schmidt law. These results suggest an important role for existing stars in helping to regulate star formation through the effect of their gravity on the midplane pressure in a wide range of galactic environments.
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Malhotra, Sangeeta, James E. Rhoads, K. Finkelstein, Huan Yang, Chris Carilli, Françoise Combes, Karine Dassas, et al. "HERSCHEL EXTREME LENSING LINE OBSERVATIONS: [C II] VARIATIONS IN GALAXIES AT REDSHIFTS z=1-3." IOP PUBLISHING LTD, 2017. http://hdl.handle.net/10150/622872.
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We observed the [C II] line in 15 lensed galaxies at redshifts 1 < z <. 3 using HIFI on the Herschel Space Observatory and detected 14/15 galaxies at 3 sigma or better. High magnifications enable even modestly luminous galaxies to be detected in [C II] with Herschel. The [C II] luminosity in this sample ranges from 8x10(7) L-circle dot to 3.7x10(9) L-circle dot (after correcting for magnification), confirming that [C II] is a strong tracer of the ISM at high redshifts. The ratio of the [C II] line to the total far-infrared (FIR) luminosity serves as a measure of the ratio of gas to dust cooling and thus the efficiency of the grain photoelectric heating process. It varies between 3.3% and 0.09%. We compare the [C II]/FIR ratio to that of galaxies at z = 0 and at high redshifts and find that they follow similar trends. The [C II]/FIR ratio is lower for galaxies with higher dust temperatures. This is best explained if increased UV intensity leads to higher FIR luminosity and dust temperatures, but gas heating does not rise due to lower photoelectric heating efficiency. The [C II]/FIR ratio shows weaker correlation with FIR luminosity. At low redshifts highly luminous galaxies tend to have warm dust, so the effects of dust temperature and luminosity are degenerate. Luminous galaxies at high redshifts show a range of dust temperatures, showing that [C II]/FIR correlates most strongly with dust temperature. The [C II] to mid-IR ratio for the HELLO sample is similar to the values seen for low-redshift galaxies, indicating that small grains and PAHs dominate the heating in the neutral ISM, although some of the high [CII]/FIR ratios may be due to turbulent heating.
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Wu, Ya-Lin, Kazushi Sakamoto, and Hsi-An Pan. "Submillimeter Array 12CO (2-1) Imaging of the NGC 6946 Giant Molecular Clouds." IOP PUBLISHING LTD, 2017. http://hdl.handle.net/10150/623951.
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We present a (CO)-C-12 (2-1) mosaic map of the spiral galaxy NGC 6946 by combining data from the Submillimeter Array and the IRAM 30m telescope. We identify 390 giant molecular clouds (GMCs) from the nucleus to 4.5 kpc in the disk. GMCs in the inner 1 kpc are generally more luminous and turbulent, some of which have luminosities > 10(6)K. km. s(-1) pc(2) and velocity dispersions > 10. km s(-1). Large-scale bar-driven dynamics likely regulate GMC properties in the nuclear region. Similar to the MilkyWay and other disk galaxies, GMC mass function of NGC 6946 has a shallower slope (index > -2) in the inner region, and a steeper slope (index < -2) in the outer region. This difference in mass spectra may be indicative of different cloud formation pathways: gravitational instabilities might play a major role in the nuclear region, while cloud coalescence might be dominant in the outer disk. Finally, the NGC 6946 clouds are similar to those inM33 in terms of statistical properties, but they are generally less luminous and turbulent than the M51 clouds.