68,875 research outputs found

    Operational considerations for the airship in short-haul transportation

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    The airship's problems and the possibilities for their solution in a short-haul transportation environment are surveyed. The problems are derived from both past experience and envisioned operation. Problems relative to both fully buoyant and semi-buoyant configurations are considered and their origins in principle discussed. Also addressed in this paper are the state-of-the-art technologies with the potential of providing answers to the airship's operational difficulties

    Seasonal Abundance and Species Diversity of Adult Tabanidae (Diptera) at Lake Lansing Park-North, Michigan

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    A two year study was undertaken to determine the seasonal abundance and diversity of adult deer flies and horse flies, to compare two methods of sampling (Malaise trap and sweep net), and to estimate attack rates by tabanids on people at Lake Lansing Park-North, Ingham County, Michigan, in 1990 and 1991. Tabanids were sampled using dry ice-baited Malaise traps, and by making over- head sweeps with a standard insect net while hiking a trail. Hybomitra spp. (299 individuals of 9 species) peaked in abundance in mid-May to early June in both years. Chrysops spp. (11,675 individuals of 14 species) and Tabanus spp. (324 individuals of 8 species) peaked in early-to late-July in both study years. Peak abundance for Chrysops and Tabanus spp. occurred earlier in 1991 than 1990, probably because the spring of 1991 was warmer. There were six new species records for County. More individual Hybomitra and Tabanus were taken by M traps (77.3% for Hybomitra; 76.2% for Tabanus) than by netting (22.7% for Hybomitra; 23.8% for Tabanus). In contrast, sweep netting yielded more individual Chrysops (98.3%) than Malaise traps (1.7%). Tabanid attack rates on people hiking the trail exceeded 1,000 per hour on one occasion each year, at mid-season

    Sustainability management : insights from the viable system model

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    A review of current literature on sustainability standards reveals a significant gap between their adoption and the implementation of sustainability into every level of the organisation. In this paper, it is argued that in order to overcome this challenge, an appropriate model of an organisation is needed. The Viable System Model (VSM) is proposed as such a model and, in order to illustrate this argument, it is used to interpret the ISO 26000 standard on Social Responsibility (SR). First, the VSM theory is introduced and presented by modelling the hypothetical company Widget Co. Then, the clauses of ISO 26000 are mapped on the Widget Co. model, together with detailed descriptions and examples on the organisational and managerial implications of its adopting the standard's guidelines. The result is the identification of generic SR functions that need to be performed by the various organisational governance systems, as well as their dynamic interrelations, thus clarifying implementation issues. Moreover, by identifying different SR management layers, VSM is suggested as a way forward to develop an integration model for SR issues and respective sustainability tools. Finally, a discussion is given on the implications of using this approach to integrate sustainability standards and the way this research contributes to recent developments in sustainability research

    Thermoelectric metal comparator determines composition of alloys and metals

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    Emf comparing device nondestructively inspects metals and alloys for conformance to a chemical specification. It uses the Seebeck effect to measure the difference in emf produced by the junction of a hot probe and the junction of a cold contact on the surface of an unknown metal
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