897 research outputs found

    Comparative Manpower Strategies

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    Dans cet article, l'Auteur traite des moyens qui sont utilisés dans les pays membres de l'OCDE pour planifier leur politique en matière de main-d'oeuvre. Pour en comprendre le sens et la portée, il faut les considérer à la lumière du développement économique de chaque pays.Lorsqu'une nation est au premier stade de son développement industriel alors que les revenus sont relativement peu élevés, le gouvernement accorde généralement priorité à la création d'entreprises nouvelles, à la croissance des investissements et à l'expansion des marchés d'exportation. Il met l'accent sur la mise en place des infrastructures: transports, sources d'énergie, moyens de communications. Il consacre aussi beaucoup de ressources à l'éducation et à la santé. De là, il découle que les programmes de main-d'oeuvre tiennent une place plutôt secondaire dans les préoccupations de l'État.Ce n'est que plus tard, que les gouvernements en viennent à concentrer plus d'efforts sur des programmes de main-d'oeuvre qui sont la conséquence d'un haut degré d'urbanisation et d'industrialisation, où les progrès technologiques sont rapides, où les postes de travail deviennent vite désuets, où des qualifications professionnelles nouvelles et toujours plus spécialisées s'imposent.En deuxième lieu, les programmes de main-d'oeuvre ont pour objet de favoriser la mobilité professionnelle, territoriale et industrielle des travailleurs, principalement ceux qui ne sont pas protégés par des conventions collectives de travail. En Europe, par exemple, la formation de la main-d'oeuvre repose principalement sur les épaules des agents économiques, syndicats et employeurs, alors que, aux États-Unis et au Canada, l'initiative a été prise la plupart du temps par les gouvernements.En troisième lieu, l'Auteur fait remarquer que le choix des gouvernements a été influencé par les coûts, d'où l'existence de deux tendances diverses. L'une de ces tendances consiste à faire absorber presque exclusivement le coût de la formation de la main-d'oeuvre par les employeurs. À l'opposé, il y a des pays où le gouvernement établit les politiques de main-d'oeuvre directement à même ses revenus sans en imposer le fardeau aux employeurs. Dans la plupart des pays de l'OCDE, on retrouve un chevauchement des deux systèmes. Il faut aussi ajouter à cela le phénomène de la création et de la conservation directes d'emplois à des fins de développement régional.En résumé, on peut dire que chacun des vingt-quatre pays membres de l'organisation possède son propre système de politiques de main-d'oeuvre que l'Auteur analyse brièvement pour les pays suivants: Canada, États-Unis, Japon, Suède, Allemagne, France, Grande-Bretagne. Il en retient qu'un système peut impliquer la coopération des associations de travailleurs et des employeurs, l'État agissant au niveau national. Sous un autre régime, il n'y aura guère de collaboration patronale-syndicale, les politiques de main-d'oeuvre relevant de l'action directe de l'État. Enfin, un troisième système repose presque entièrement sur les employeurs, ce qui ne laisse qu'une responsabilité résiduelle au gouvernement.The author presents a comparison of how different member countries of the OECD have developed their man-power strategies over the past decade in light of the unique institutional and cultural circumstances

    Taux de roulement et permanence de l’emploi dans l’industrie canadienne

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    This study poses the question: "How long will the average new employee likely stay with his employer? This question has considerable relevance to the study of labour market activity, and to the obverse question: "How likely will a person, once employed, be unemployed again?" This paper explores the relevance of the tenure question on a number of fronts, and then develops a simple model for estimating the expected tenure of workers joining specific industries in Canada. Although the findings are based on somewhat dated statistics and lack a vector related to age, sex and other personal characteristics, they nonetheless confirm within reasonable degrees of confidence that the average new employee will remain with his employer a remarkably short time—less than two years in most industries and only a few months in some others. They suggest that employers are wise to defer costly training, pension and other non-wage expenditures until their new employees have built up some attachment to the firm. By the same token they affirm the usefulness of public income support programs to tide those who are laid off or quit through the transition to their next job, and for public retraining and mobility facilities to make the investments in human skills and allocation that employers will not.

    Feasibility study of the transonic biplane concept for transport aircraft application

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    Investigations were conducted to evaluate the feasibility of a transonic biplane consisting of a forward-mounted swept-back lower wing, a rear-mounted swept-forward upper wing, and a vertical fin connecting the wings at their tips. This wing arrangement results in significant reductions in induced drag relative to a monoplane designed with the same span, and it allows for a constant-section fuselage shape while closely matching an ideal area distribution curve for M = 0.95 cruise. However, no significant reductions in ramp weight were achieved for the biplane relative to a monoplane with the same mission capability. Flutter analyses of the biplane revealed both symmetric and antisymmetric instabilities that occur well below the required flutter speed. Further studies will be required to determine if acceptable flutter speeds can be achieved through the elimination of the instabilities by passive means or by active controls. Configurations designed for other missions, especially those with lower Mach numbers and lower dynamic pressures, should be examined since the geometries suitable for those design constraints might avoid the weight penalties and flutter instabilities which prevent exploitation of induced drag benefits for the configuration studied

    Properties of Calcium Caseinates With Disparate Performance in Imitation Cheese

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    Two commercial lots of calcium caseinate preparations differing in performance imitation cheese were analyzed for various characteristics. A imitation process cheese manufacturing classified the caseinates as good or poor based on appearances of the finished cheese, emulsification of fat, oiling-off during sheeting and melting properties. The sample which exhibited good functional properties in imitation cheese, had slightly higher calcium (16.4 mg/g protein), non-casein protein (2.87%) and y-casein contents, a higher formal titre (8.95 mg free amino N/g protein), lower water absorption (138 mg/100 g protein), and lower stability to added calcium (8.0 min) than did the other sample (14.6 mg/g, 1.66%, 8.02 mg/g, 129 mg/100 g, and 15 min, respectively), which was described as having poor functionality according to the criteria of the imitation cheese producer

    The very flat radio - millimetre spectrum of Cygnus X-1

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    We present almost-simultaneous detections of Cygnus X-1 in the radio and mm regimes, obtained during the low/hard X-ray state. The source displays a flat spectrum between 2 and 220 GHz, with a spectral index flatter than 0.15 (3sigma). There is no evidence for either a low- or high-frequency cut-off, but in the mid-infrared (~30 microns) thermal emission from the OB-type companion star becomes dominant. The integrated luminosity of this flat-spectrum emission in quiescence is > 2 x 10^{31} erg/s (2 x 10^{24} W). Assuming the emission originates in a jet for which non-radiative (e.g. adiabatic expansion) losses dominate, this is a very conservative lower limit on the power required to maintain the jet. A comparison with Cyg X-3 and GRS 1915+105, the other X-ray binaries for which a flat spectrum at shorter than cm wavelengths has been observed, shows that the jet in Cyg X-1 is significantly less luminous and less variable, and is probably our best example to date of a continuous, steady, outflow from an X-ray binary. The emissive mechanism reponsible for such a flat spectral component remains uncertain. Specifically, we note that the radio-mm spectra observed from these X-ray binaries are much flatter than those of the `flat-spectrum' AGN, and that existing models of synchrotron emission from partially self-absorbed radio cores, which predict a high-frequency cut-off in the mm regime, are not directly applicable.Comment: Accepted for publication in MNRA

    SCUBA - A submillimetre camera operating on the James Clerk Maxwell Telescope

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    The Submillimetre Common-User Bolometer Array (SCUBA) is one of a new generation of cameras designed to operate in the submillimetre waveband. The instrument has a wide wavelength range covering all the atmospheric transmission windows between 300 and 2000 microns. In the heart of the instrument are two arrays of bolometers optimised for the short (350/450 microns) and long (750/850 microns) wavelength ends of the submillimetre spectrum. The two arrays can be used simultaneously, giving a unique dual-wavelength capability, and have a 2.3 arc-minute field of view on the sky. Background-limited performance is achieved by cooling the arrays to below 100 mK. SCUBA has now been in active service for over a year, and has already made substantial breakthroughs in many areas of astronomy. In this paper we present an overview of the performance of SCUBA during the commissioning phase on the James Clerk Maxwell Telescope (JCMT).Comment: 14 pages, 13 figures (1 JPEG), Proc SPIE vol 335

    New light on the S235A-B star forming region

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    The S235A-B star forming region has been extensively observed in the past from the radio to the near-IR, but what was happening in the immediate surroundings of the water maser, placed in between the two nebulosities, was still unclear because of insufficient resolution especially in the spectral range from the Far-IR to the mm, even though there were sound indications that new young stellar objects (YSOs) are being formed there. We present here new high resolution maps at mm wavelengths in different molecules (HCO+, C34S, H2CS, SO2 and CH3CN), as well as in the 1.2 and 3.3 mm continuum obtained with the Plateau de Bure interferometer, and JCMT observations at 450 micron and 850 micron that unambiguously reveal the presence of new YSOs placed in between the two HII regions S235A and S235B and associated with the water maser. A molecular core and an unresolved source in the mm and in the sub-mm are centred on the maser, with indication of mass infall onto the core. Two molecular bipolar outflows and a jet originate from the same position. Weak evidence is found for a molecular rotating disk perpendicular to the direction of the main bipolar outflow. The derived parameters indicate that one of the YSOs is an intermediate luminosity object (L~1000 Lsun) in a very early evolutionary phase, embedded in a molecular core of ~100 Msun, with a temperature of 30 K. The main source of energy for the YSO could come from gravitational infall, thus making of this YSO a rare example of intermediate luminosity protostar representing a link between the earliest evolutionary phases of massive stars and low mass protostars of class 0-I.Comment: 19 pages, 22 figures, to be published in Astronomy & Astrophysic

    Resolving the Submillimeter Background: the 850-micron Galaxy Counts

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    Recent deep blank field submillimeter surveys have revealed a population of luminous high redshift galaxies that emit most of their energy in the submillimeter. The results suggest that much of the star formation at high redshift may be hidden to optical observations. In this paper we present wide-area 850-micron SCUBA data on the Hawaii Survey Fields SSA13, SSA17, and SSA22. Combining these new data with our previous deep field data, we establish the 850-micron galaxy counts from 2 mJy to 10 mJy with a >3-sigma detection limit. The area coverage is 104 square arcmin to 8 mJy and 7.7 square arcmin to 2.3 mJy. The differential 850-micron counts are well described by the function n(S)=N_0/(a+S^3.2), where S is the flux in mJy, N_0=3.0 x 10^4 per square degree per mJy, and a=0.4-1.0 is chosen to match the 850-micron extragalactic background light. Between 20 to 30 per cent of the 850-micron background resides in sources brighter than 2 mJy. Using an empirical fit to our >2 mJy data constrained by the EBL at lower fluxes, we argue that the bulk of the 850-micron extragalactic background light resides in sources with fluxes near 1 mJy. The submillimeter sources are plausible progenitors of the present-day spheroidal population.Comment: 5 pages, accepted by The Astrophysical Journal Letter

    Multi-Generational Star Formation in L1551

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    The L1551 molecular cloud contains two small clusters of Class 0 and I protostars, as well as a halo of more evolved Class II and III YSOs, indicating a current and at least one past burst of star formation. We present here new, sensitive maps of 850 and 450 um dust emission covering most of the L1551 cloud, new CO J=2-1 data of the molecular cloud, and a new, deep, optical image of [SII] emission. No new Class 0/I YSOs were detected. Compact sub-millimetre emitters are concentrated in two sub-clusters: IRS5 and L1551NE, and the HL~Tauri group. Both stellar groups show significant extended emission and outflow/jet activity. A jet, terminating at HH 265 and with a very weak associated molecular outflow, may originate from LkHa 358, or from a binary companion to another member of the HL Tauri group. Several Herbig Haro objects associated with IRS5/NE were clearly detected in the sub-mm, as were faint ridges of emission tracing outflow cavity walls. We confirm a large-scale molecular outflow originating from NE parallel to that from IRS5, and suggest that the "hollow shell" morphology is more likely due to two interacting outflows. We confirm the presence of a prestellar core (L1551-MC) of mass 2-3 Mo north-west of IRS5. The next generation cluster may be forming in this core. The L1551 cloud appears cometary in morphology, and appears to be illuminated and eroded from the direction of Orion, perhaps explaining the multiple episodes of star formation in this cloud. The full paper (including figures) can be downloaded at http://www.jach.hawaii.edu/~gms/l1551/l1551-apj641.pdf, or viewed at http://www.jach.hawaii.edu/~gms/l1551/.Comment: Accepted for publication in The Astrophysical Journal, April 2006 (vol. 641). 27 pages, 17 figure

    CHIMPS: the <sup>13</sup>CO/C<sup>18</sup>O (<i>J</i> = 3 → 2) Heterodyne Inner Milky Way Plane Survey

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    We present the 13CO/C18O (J = 3 → 2) Heterodyne Inner Milky Way Plane Survey (CHIMPS) which has been carried out using the Heterodyne Array Receiver Program on the 15 m James Clerk Maxwell Telescope (JCMT) in Hawaii. The high-resolution spectral survey currently covers |b| ≤ 0.5° and 28° ≲ l ≲ 46°, with an angular resolution of 15 arcsec in 0.5 km s-1 velocity channels. The spectra have a median rms of ˜0.6 K at this resolution, and for optically thin gas at an excitation temperature of 10 K, this sensitivity corresponds to column densities of NH2 ˜ 3 × 1020 cm-2 and NH2 ˜ 4 × 1021 cm-2 for 13CO and C18O, respectively. The molecular gas that CHIMPS traces is at higher column densities and is also more optically thin than in other publicly available CO surveys due to its rarer isotopologues, and thus more representative of the three-dimensional structure of the clouds. The critical density of the J = 3 → 2 transition of CO is ≳104 cm-3 at temperatures of ≤20 K, and so the higher density gas associated with star formation is well traced. These data complement other existing Galactic plane surveys, especially the JCMT Galactic Plane Survey which has similar spatial resolution and column density sensitivity, and the Herschel infrared Galactic Plane Survey. In this paper, we discuss the observations, data reduction and characteristics of the survey, presenting integrated-emission maps for the region covered. Position-velocity diagrams allow comparison with Galactic structure models of the Milky Way, and while we find good agreement with a particular four-arm model, there are some significant deviations
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