8,466 research outputs found
Improved relay optical element for spectroradiometer using cryogenically cooled detector
By coating half of one element in the relay optical system of a spectroradiometer with a very high emissivity paint, the effect of the reflected radiation from the back of the filter wheel is eliminated optically. This causes the detector to view a constant level of radiation, regardless of how the reflectivity of the back of the filter wheel changes
Observations of Outflowing UV Absorbers in NGC 4051 with the Cosmic Origins Spectrograph
We present new Hubble Space Telescope (HST)/Cosmic Origins Spectrograph
observations of the Narrow-Line Seyfert 1 galaxy NGC 4051. These data were
obtained as part of a coordinated observing program including X-ray
observations with the Chandra/High Energy Transmission Grating (HETG)
Spectrometer and Suzaku. We detected nine kinematic components of UV
absorption, which were previously identified using the HST/Space Telescope
Imaging Spectrograph. None of the absorption components showed evidence for
changes in column density or profile within the \sim 10 yr between the STIS and
COS observations, which we interpret as evidence of 1) saturation, for the
stronger components, or 2) very low densities, i.e., n_H < 1 cm^-3, for the
weaker components. After applying a +200 km s^-1 offset to the HETG spectrum,
we found that the radial velocities of the UV absorbers lay within the O VII
profile. Based on photoionization models, we suggest that, while UV components
2, 5 and 7 produce significant O VII absorption, the bulk of the X-ray
absorption detected in the HETG analysis occurs in more highly ionized gas.
Moreover, the mass loss rate is dominated by high ionization gas which lacks a
significant UV footprint.Comment: 41 pages, 10 Figures; accepted for publication in the Astrophysical
Journa
Whose forests, whose voices? Mining and community- based nature conservation in southeastern Madagascar
This paper explores local experiences of private - sector led community - based nature conservation near Fort Dauphin, southeastern Madagascar through the analysis of a conservation zone managed in partnership between the Rio Tinto mining corporation, local government and local communities. The article assesses how new forms of social inclusion and exclusion are generated through changes in land and resource access. The main findings are as follows: the community - based conservation programs near the Fort Dauphin mine were effective at mobilising local people but inadvertently favored certain members of society over others, as they involved a legitimization of resource access by established landowners. This granting of resource rights to some local users entailed the exclusion of already marginalised groups of landless migrants. Without land to cultivate, these migrants were more directly dependent on forest resources for their survival. Their livelihoods were based on selling forest products such as timber and handicrafts, in addition to working the land of others. This rendered their social status and ability to participate in development programs limited. Non - resident or recently settled resource users’ voices had thereby not been adequately included in the conservation plans from the outset. Consequently, local landless migrants continued to break conservation rules, as they had no influence over the resource management process or realistic livelihoods alternatives. These circumstances reduced both the livelihood options of the poorest people near the mining site and the prospect of achieving equitable and sustainable natural resource management.RÉSUMÉNous proposons ici d’analyser des expériences locales intervenant lors du changement d’accès aux ressources naturelles dans le cadre d’un projet d’extraction minière et de conservation de la nature mené en partenariat entre une compagnie minière, le gouvernement local et les communautés riveraines d’un site minier près de Fort Dauphin, dans le Sud - est de Madagascar. Les informations ont été recueillies lors d’une année de recherches ethnographiques financées par le Conseil de Recherche Norvégien, aux alentours de la zone minière et de son site de conservation. Les changements d’accès à la terre et aux ressources naturelles induisent de nouveaux types d’inclusion et d’exclusion sociaux que nous avons étudiés ici. Nous montrons que les programmes communautaires de conservation de la nature et de développement local établis auprès du site minier ont permis de mobiliser les villageois riverains, mais ont par mégarde créé des disparités entre certains membres de la société locale. Nous avons ainsi noté une augmentationde la différentiation sociale des propriétaires terriens traditionnels qui pouvaient revendiquer la légitimation des accès aux ressources naturelles. Cette légitimation se déroulait au cours d’une approche participative de cogestion environnementale, qui supposait un rang social élevé des participants mais aussi leur disponibilité pour pouvoir participer à ces programmes communautaires. Certains groupes extrêmement vulnérables comme les migrants sans terres ont ainsi été involontairement exclus à cause de cet octroi du droit d’accès aux ressources naturelles en faveur de certains groupes d’utilisateurs. En outre, sans terre à cultiver, ces migrants dépendaient encore davantage des ressources forestières pour assurer leur survie quotidienne. Leurs moyens de subsistance se limitaient à la vente de produits forestiers tels que le bois d’oeuvre ou encore les roseaux pour l’artisanat. Une autre stratégie de survie importante pour les migrants sans terre était d’assurer la culture des terrains des propriétaires existants, permettant ainsi ces derniers à participer plus activement aux nouveaux programmes de gestion et développement local. En outre, les personnes les plus marginalisées résidaient souvent à l’extérieur des communes qui hébergeaient la zone de conservation et d’extraction minière, dans la mesure où il n’y avait plus de terre disponible dans ces communes. Le programme de conservation communautaire mené par la corporation minière était basé sur la mise en relation du droit aux ressources naturelles et de la résidence dans la commune hébergeant ces ressources. Or les personnes résidant hors de ces communes ou les personnes récemment installées et de statut social bas, étaient ainsi exclues dans la planification et la mise en oeuvre de la gestion communautaire des ressources locales. Par conséquent, les migrants sans terre ne respectaient pas les lois de conservation communautaire, car ils n’ont pas pu influencer la procédure d’établissement des règles de gestion conjointes, ni accéder aux programmes d’activités génératrices de revenus alternatifs. Ces circonstances ont ainsi fait ressortir les limites de l’approche de conservation communautaire destinée à atténuer les impacts environnementaux du projet minier et à résoudre les conflits sociaux y afférents
Crew interface definition study, phase 1
The timeline analysis of the Shuttle orbiter missions which was conducted in the Phase I Crew Interface Definition Study and the requirements for the man-in-the-loop simulation study are presented. Mission definitions and objectives are presented as they relate to various Shuttle Orbiter missions. The requirements for crew participation and the information required by the crew are discussed, and finally the rationale behind the display concept and calling procedures is given. The simulation objectives, the simulation mechanization, including a detailed presentation of the display and control concept, the simulator test plan and the results are discussed
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The effects of electronic meetings on group processes and outcomes: An assessment of the empirical research
In this paper we analyze the empirical research on the impacts of electronic meetings on group processes and outcomes. We define and differentiate two broad types of electronic meeting systems: Group Decision Support Systems (GDSS) and Group Communication Support Systems (GCSS). We then present a framework and method for analyzing the impacts of such information systems on groups that we develop from the literature of organization behavior and group psychology. We review the empirical research and findings concerned with the impacts of GDSS and GCSS on groups, and we compare and contrast these findings. Finally, we conclude by discussing the implications of our analysis on the focus of attention and the design of future research. Our review of the empirical research suggests that GDSS and GCSS have similar impacts on some aspects of group processes and outcomes, but opposite impacts on other aspects. GDSS and GCSS both increase the depth of analysis of groups, increase participation, decrease domination by a few members, and increase decision quality. On the other hand, GDSS increase consensus reaching, decrease decision time, increase confidence in the decision by the group members, increase the satisfaction of group members with the process, and increase the satisfaction of the group members with the decision. GCSS decrease cooperation, increase the time to reach a decision, and decrease the confidence in decisions. © 1990
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The impact of technological support on groups: An assessment of the empirical research
In this paper we analyze the empirical findings on the impacts of technological support on group. We define and differentiate two broad technological support systems for group processes: Group Decision Support Systems (GDSS), and Group Communication Support Systems (GCSS). We then present a framework and method for analyzing the impacts of such information systems on groups. We develop the framework from the literature of organization behavior and group psychology and apply it to literature of MIS. We then review the empirical research and findings concerned with the impacts of GDSS and GCSS on groups, and we compare and contrast these findings. Finally, we conclude by discussing the implications of our analysis on the focus of attention and design of future research. Five Major implications stem from our analysis: (1) there is lack of research on some important "formal" factors of groups, (2) there is a paucity of research on the impacts of GDSS and GCSS on the informal dimension of groups, (3) there is a need to move away from laboratory settings to field study in organization settings, with "real" manager, (4) more research is needed on stages of group development and on how they affect the impacts of GDSS and GCSS on groups, and (5) more research is needed to understand how the structure imposed by the technological supports affect group processes. © 1989
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Exploring the role of information technology in organizational downsizing: A tale of two American cities
This study explores the role information technology (IT) plays in organizational downsizing by studying two medium-sized American cities over a period of 10 years (1985-1995). Data were collected through 73 interviews, a questionnaire, and numerous documents. Four main findings emerged from the case studies. First, IT was found to facilitate organizational downsizing, but not to cause it. New City invested heavily in state-of-the-art IT over the years and more successfully downsized the organization than Old City, which lagged behind in IT investment and made no serious attempts to use IT as a tool to support strategic actions. Second, adverse environmental conditions triggered downsizing in both cities and determined the change strategies that managers used. When environmental pressures were mild (1985-1990), managers favored a convergent change strategy that resulted in limited downsizing efforts and small personnel reductions. In contrast, when environmental pressures were strong (1990-1995), managers of both cities engaged in strategic reorientation and in downsizing efforts that led to larger personnel reductions. Third, the role IT played in organizational downsizing varied according to the change strategy. IT was used to facilitate work redesign in a convergent change strategy and to facilitate more significant structural and work redesign in strategic reorientation. Fourth, more integrated and better use of IT allowed managers of New City to downsize more rationally and efficiently.It facilitated the transfer of personnel within departments, from middle management to the operations level, and across departments, from internally oriented to customer-oriented personnel. In doing so, managers of New City minimized operating costs while maintaining the same level of services. In contrast, IT in Old City did not facilitate such an agenda and managers downsized more superficially across the board, in all departments. Differences in IT consequences in the two cities are explained using the theory of slack resources in organizations
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