Du bien-être psychologique au travail : fondements théoriques, conceptualisation et instrumentation du construit

Malgré la préoccupation croissante des chercheurs et praticiens pour la santé psychologique au travail, le concept de bien-être vécu au travail est encore mal compris de la communauté scientifique. En effet, peu d’efforts ont été consacrés à ce jour pour développer des connaissances sur le bien-être psychologique au travail arrimées à la réalité des employés. Cette thèse a donc pour objectif de développer une conceptualisation du bien-être psychologique au travail et une instrumentation psychométriquement fiable lui étant rattachée. Pour ce faire, deux études ont été réalisées. La première, de nature qualitative et exploratoire, fut menée auprès de 20 travailleurs canadiens francophones afin de répertorier, à partir d’incidents critiques vécus par ceux-ci, des manifestations de bien-être psychologique au travail. Celles-ci ont pu être classifiées selon un modèle en 2 axes, soit la sphère de référence dans laquelle le bien-être psychologique au travail se vit et la directionnalité selon laquelle il se développe. Ce modèle a ensuite été comparé aux conceptualisations génériques du bien-être psychologique existantes, et cette analyse a permis d’étayer la validité convergente et divergente du modèle. Dans un deuxième temps, l’Indice de bien-être psychologique au travail (IBEPT) a été créé sur la base des manifestations relevées lors de l’étude qualitative, afin d’en assurer la validité de contenu. Une version expérimentale de l’instrument a ensuite été soumise à une expérimentation auprès de 1080 travailleurs québécois. Les analyses factorielles exploratoires révèlent une structure interne en 25 items reflétant 5 dimensions, représentant elles-mêmes un construit de second ordre. La validité de construit de cette conceptualisation a ensuite été étudiée par l’analyse des intercorrélations avec une série de mesures du bien-être et de la détresse psychologique génériques. Les résultats appuient la validité convergente de l’instrument, et démontrent également sa validité divergente. Enfin, l’instrument affiche une cohérence interne satisfaisante. Au terme de cette recherche doctorale, les résultats des deux études sont interprétés en fonction de l’état actuel des connaissances sur le bien-être psychologique, les limites des études sont énoncées, et des pistes de recherche future sont avancées.

La santé psychologique au travail : conceptualisation, instrumentation et facteurs organisationnels de développement

Thèse numérisée par la Division de la gestion de documents et des archives de l'Université de Montréal

A layered JavaScript virtual machine supporting dynamic instrumentation

L’observation de l’exécution d’applications JavaScript est habituellement réalisée en instrumentant une machine virtuelle (MV) industrielle ou en effectuant une traduction source-à-source ad hoc et complexe. Ce mémoire présente une alternative basée sur la superposition de machines virtuelles. Notre approche consiste à faire une traduction source-à-source d’un programme pendant son exécution pour exposer ses opérations de bas niveau au travers d’un modèle objet flexible. Ces opérations de bas niveau peuvent ensuite être redéfinies pendant l’exécution pour pouvoir en faire l’observation. Pour limiter la pénalité en performance introduite, notre approche exploite les opérations rapides originales de la MV sous-jacente, lorsque cela est possible, et applique les techniques de compilation à-la-volée dans la MV superposée. Notre implémentation, Photon, est en moyenne 19% plus rapide qu’un interprète moderne, et entre 19× et 56× plus lente en moyenne que les compilateurs à-la-volée utilisés dans les navigateurs web populaires. Ce mémoire montre donc que la superposition de machines virtuelles est une technique alternative compétitive à la modification d’un interprète moderne pour JavaScript lorsqu’appliqué à l’observation à l’exécution des opérations sur les objets et des appels de fonction.

Compact amplifier integrated microstrip antenna

compact microstrip antenna integrated with an amplifier having an area reduction of 70%, compared to the standard circular microstrip patch antenna, is presented. The antenna also provides an enhanced gain of 10-dB more than its passive counter part. The measured 2:1 VSWR band width is -4% at 790 MHz, which is 2.5 times larger than that of the passive microstrip antenna

Fabrication and characterization of dye-doped polymer optical fiber as a light amplifier

The fabrication and characterization of a Rhodamine 6G-doped polymer optical fiber amplifier have been carried out. Two different schemes were employed to characterize the optical fiber: the stripe illumination technique to study the fiber as a gain medium and another technique to study its performance as an amplifier. We observed a spectral narrowing from 42 to 7 nm when the pump energy was increased to 6 mJ in the stripe illumination geometry. A gain of 18 dB was obtained in the amplifier configuration. The effects of pump power and dye concentration on the performance of the fiber as an amplifier were also studied.

Fabrication and characterization of dye mixture doped polymer optical fiber as a broad wavelength optical amplifier

Rhodamine 6G and Rhodamine B dye mixture doped polymer optical fiber amplifier (POFA), which can operate in a broad wavelength region (60 nm), has been successfully fabricated and tested. Tunable operation of the amplifier over a broad wavelength region is achieved by mixing different ratios of the dyes. The dye doped POFA is pumped axially using 532 nm, 10 ns laser pulses from a frequency doubled Q-switched Nd: YAG laser and the signals are taken from an optical parametric oscillator. A maximum gain of 22.3 dB at 617 nm wavelength has been obtained for a 7 cm long dye mixture doped POFA. The effects of pump energy and length of the fiber on the performance of the fiber amplifier are also studied. There exists an optimum length for which the amplifier gain is at a maximum value.

Design and Development of Instrumentation Systems to determine the Dry Rubber Content in Natural Rubber Latex

Hevea latex is a natural biological liquid of very complex composition .Besides rubber hydrocarbons,it contains many proteinous and resinous substances,carbohydrates,inorganic matter,water,and others.The Dry Rubber Content (DRC) of latex varies according to season, tapping system,weather,soil conditions ,clone,age of the tree etc. The true DRC of the latex must be determined to ensure fair prices for the latex during commercial exchange.The DRC of Hevea latex is a very familiar term to all in the rubber industry.It has been the basis for incentive payments to tappers who bring in more than the daily agreed poundage of latex.It is an important parameter for rubber and latex processing industries for automation and verious decesion making processes.This thesis embodies the efforts made by me to determine the DRC of rubber latex following different analytical tools such as MIR absorption,thermal analysis.dielectric spectroscopy and NIR reflectance.The rubber industry is still Looking for a compact instrument that is accurate economical,easy to use and environment friendly.I hope the results presented in this thesis will help to realise this goal in the near future.

Laser Spectroscopy: TDLAS instrumentation and NIR analysis of some organic materials

Near-infrared spectroscopy can be a workhorse technique for materials analysis in industries such as agriculture, pharmaceuticals, chemicals and polymers. A near-infrared spectrum represents combination bands and overtone bands that are harmonics of absorption frequencies in the mid-infrared. Near-infrared absorption includes a combination-band region immediately adjacent to the mid-infrared and three overtone regions. All four near-infrared regions contain "echoes" of the fundamental mid-infrared absorptions. For example, vibrations in the mid-infrared due to the C-H stretches will produce four distinct bands in each of the overtone and combination regions. As the bands become more removed from the fundamental frequencies they become more widely separated from their neighbors, more broadened and are dramatically reduced in intensity. Because near-infrared bands are much less intense, more of the sample can be used to produce a spectra and with near-infrared, sample preparation activities are greatly reduced or eliminated so more of the sample can be utilized. In addition, long path lengths and the ability to sample through glass in the near-infrared allows samples to be measured in common media such as culture tubes, cuvettes and reaction bottles. This is unlike mid-infrared where very small amounts of a sample produce a strong spectrum; thus sample preparation techniques must be employed to limit the amount of the sample that interacts with the beam. In the present work we describe the successful the fabrication and calibration of a linear high resolution linear spectrometer using tunable diode laser and a 36 m path length cell and meuurement of a highly resolved structure of OH group in methanol in the transition region A v =3. We then analyse the NIR spectrum of certain aromatic molecules and study the substituent effects using local mode theory

Project for instrumentation in education

This paper describes an audio/visual project resulting in a public relations slide slow about Central Institute for the Deaf and its facilities and activities.

Mid-infrared filters for astronomical and remote sensing instrumentation

As improvements to the optical design of spectrometer and radiometer instruments evolve with advances in detector sensitivity, use of focal plane detector arrays and innovations in adaptive optics for large high altitude telescopes, interest in mid-infrared astronomy and remote sensing applications have been areas of progressive research in recent years. This research has promoted a number of developments in infrared coating performance, particularly by placing increased demands on the spectral imaging requirements of filters to precisely isolate radiation between discrete wavebands and improve photometric accuracy. The spectral design and construction of multilayer filters to accommodate these developments has subsequently been an area of challenging thin-film research, to achieve high spectral positioning accuracy, environmental durability and aging stability at cryogenic temperatures, whilst maximizing the far-infrared performance. In this paper we examine the design and fabrication of interference filters in instruments that utilize the mid-infrared N-band (6-15 µm) and Q-band (16-28 µm) atmospheric windows, together with a rationale for the selection of materials, deposition process, spectral measurements and assessment of environmental durability performance.

Fine wire resistance thermometer amplifier for atmospheric measurements

An improved amplifier for atmospheric fine wire resistance thermometry is described. The amplifier uses a low excitation current (50 mu A). This is shown to ensure negligible self-heating of the low mass fine wire resistance sensor, compared with measured nocturnal surface air temperature fluctuations. The system provides sufficient amplification for a +/- 50 degrees C span using a +/- 5 V dynamic range analog-to-digital converter, with a noise level of less than 0.01 degrees C. A Kelvin four-wire connection cancels the effect of long lead resistances: a 50 m length of screened cable connecting the Reading design of fine wire thermometer to the amplifier produced no measurable temperature change at 12 bit resolution.