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21.
Generally speaking, today's TQEM initiatives do not improve a firm's activities beyond the shipping dock and onto consumer and postconsumer use and reuse. Although internal TQEM efforts do improve environmental impacts of a firm's operations, most firms remain focused on the traditional bottom-line objective of increasing throughput. For these reasons, most firms implementing TQEM miss the many opportunities to improve environmental performance (including cost and quality) through asset recovery, resource sharing, and reuse. However, by taking the advantages of teamwork beyond corporate boundaries, firms can close the loop on environmental improvements. Inter-firm teaming for environmental advantage, which we define as TQEM alliancing, initiates a cyclical approach to environmental performance improvement. It does so by forging strategic relationships among firms that can leverage each other's environmental weaknesses. TQEM allying is a round-robin game plan. In this article, the authors show how it allows firms to take their environmental improvement initiatives beyond regulatory compliance (and into proactivity), beyond pollution control (to total pollution avoidance), and beyond profitability (for a quantitative as well as qualitative bottom line), because firms will be integrating external as well as internal functions across different business domains. 相似文献
22.
Aspects of transboundary, water shortage, and fisheries issues are discussed in the context of the recently completed Global International Waters Assessment (GIWA) for the Pacific Islands. The region encompasses some 30 million km2 and approximately 12% of the world's ocean space, and features great geographic, demographic and developmental diversity. Global change, especially sea level rise and sea surface temperature increases, is the dominant transboundary concern as it impacts all aspects of life. Water shortage and unsustainable fishing issues are selected for discussion, as they will dominate the region into the foreseeable future, and they are illustrated with examples from Fiji, Kiribati, and Tonga. The environmental impacts are exacerbated by socioeconomic issues such as high population growth rates, urban drift, the breakdown of traditional life styles and the rapid adoption of the cash economy. Policy options that may assist in addressing these issues are proposed. 相似文献
23.
Pratt SC 《Die Naturwissenschaften》2000,87(1):33-35
Honey bees have long been assumed to build their comb with the cells in either of two preferred orientations with respect
to gravity ("vertical" or "horizontal"). I show here that these typical cell orientations in fact derive from substrate orientation
and a simple building rule, rather than the influence of gravity itself. When bees were induced to build comb on substrates
at four different orientations with respect to gravity, they always made cells with one vertex pointing directly toward the
substrate. This produced horizontal and vertical cells on vertical and horizontal substrates, respectively, but yielded intermediate
orientations on oblique substrates. The apparent preference for vertical and horizontal cells may simply reflect substrate
orientation in the rectilinear hives from which cell measurements have been taken.
Received: 27 July 1999 / Accepted in revised form: 20 September 1999 相似文献
24.
Ethanol fuel production is growing rapidly in the rural Midwest, and this growth presents potential environmental impacts. In 2002, the U.S. Environmental Protection Agency (EPA) and the Minnesota Pollution Control Agency (MPCA) entered into enforcement actions with 12 fuel ethanol plants in Minnesota. The enforcement actions uncovered underreported emissions and resulted in consent decrees that required pollution control equipment be installed. A key component of the consent decrees was a requirement to conduct emissions tests for volatile organic compounds (VOCs) with the goal of improving the characterization and control of emissions. The conventional VOC stack test method was thought to underquantify total VOC emissions from ethanol plants. A hybrid test method was also developed that involved quantification of individual VOC species. The resulting database of total and speciated VOC emissions from 10 fuel ethanol plants is relatively small, but it is the most extensive to date and has been used to develop and gauge compliance with permit limits and to estimate health risks in Minnesota. Emissions were highly variable among facilities and emissions units. In addition to the variability, the small number of samples and the presence of many values below detection limits complicate the analysis of the data. To account for these issues, a nested bootstrap procedure on the Kaplan-Meier method was used to calculate means and upper confidence limits. In general, the fermentation scrubbers and fluid bed coolers emitted the largest mass of VOC emissions. Across most facilities and emissions units ethanol was the pollutant emitted at the highest rate. Acetaldehyde, acetic acid, and ethyl acetate were also important emissions from some units. Emissions of total VOCs, ethanol, and some other species appeared to be a function of the beer feed rate, although the relationship was not reliable enough to develop a production rate-based emissions factor. 相似文献
25.
Hansford GM Freshwater RA Bosch RA Cox RA Jones RL Pratt KF Williams DE 《Journal of environmental monitoring : JEM》2005,7(2):158-162
The design of an instrument based on a solid state tungsten oxide sensor for making profile measurements of atmospheric ozone from balloon platforms is described. The sensor is operated at a constant temperature, typically 530 [degree]C. The importance of a detailed consideration of the electronic design is demonstrated, with particular reference to the circuit to control the sensor heater. Calibration methods which are straightforward to implement are illustrated, and the results of a test flight alongside an electrochemical ozonesonde are shown. Quantitative agreement within 25% for most of the profile demonstrates the potential of this type of sensor for ozone sounding. Future improvements from manufacture to analysis are expected to improve on this. 相似文献
26.
The debate on valuing the environment moved to the fore in Britain in the late 1980s, principally as the result of the interaction of two factors: growing party political competition on the environment; and difficulties the Conservative Government were experiencing in defining a distinct neo‐liberal agenda for the environment. Despite its technocratic overtones, valuing the environment has thus become part of a broader political debate. Moreover, there are a number of radical implications for decision making and the role of conservation organizations which flow from an adoption of valuation practices and we seek to identify these as well. 相似文献
27.
Ramachandran G Adgate JL Hill N Sexton K Pratt GC Bock D 《Journal of the Air & Waste Management Association (1995)》2000,50(7):1157-1166
Measurements of 15-min average PM2.5 concentrations were made with a real-time light-scattering instrument at both outdoor (central monitoring sites in three communities) and indoor (residential) locations over two seasons in the Minneapolis-St. Paul metropolitan area. These data are used to examine within-day variability of PM2.5 concentrations indoors and outdoors, as well as matched indoor-to-outdoor (I/O) ratios. Concurrent gravimetric measurements of 24-hr average PM2.5 concentrations were also obtained as a way to compare real-time measures with this more traditional metric. Results indicate that (1) within-day variability for both indoor and outdoor 15-min average PM2.5 concentrations was substantial and comparable in magnitude to day-to-day variability for 24-hr average concentrations; (2) some residences exhibited substantial variability in indoor aerosol characteristics from one day to the next; (3) peak values for indoor short-term (15-min) average PM2.5 concentrations routinely exceeded 24-hr average outdoor values by factors of 3-4; and (4) relatively strong correlations existed between indoor and outdoor PM2.5 concentrations for both 24-hr and 15-min averages. 相似文献
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29.
Social insect colonies possess remarkable abilities to select the best among several courses of action. In populous societies with highly efficient recruitment behaviour, decision-making is distributed across many individuals, each acting on limited local information with appropriate decision rules. To investigate the degree to which small societies with less efficient recruitment can also employ distributed decision-making, we studied nest site selection in Leptothorax albipennis. Colonies were found to make sophisticated choices, taking into account not only the intrinsic qualities of each site, but also its value relative to the available options. In choices between two sites, individual ants were able to visit both sites, compare them and choose the better one. However, most ants encountered only one site in the course of an emigration. These poorly informed ants also contributed to the colony's decision, because their probability of initiating recruitment to a site depended on its quality. This led to shorter latencies between discovery and recruitment to a superior site, and so created greater amplification via positive feedback of the population at the better site. In short, these small colonies make use of a distributed mechanism of information processing, but also take advantage of direct decision-making by well-informed individuals. The latter feature may in part stem from the limitations of their social structure, but may also reflect the stringent demand for unanimous decisions by house-hunting colonies of any size. 相似文献
30.
Stephen C. Pratt 《Behavioral ecology and sociobiology》1999,46(1):30-42
Honeybee colonies, like organisms, should exhibit optimal design in their temporal pattern of resource allocation to somatic
structures. A vital colony structure is the comb which stores honey for overwinter survival. However, the timing of comb construction
poses a dilemma to a colony attempting to maximize its honey reserves. On the one hand, plenty of empty comb is needed for
efficient exploitation of temporally unpredictable flower blooms. On the other hand, because comb is made from energetically
expensive wax, its construction too early or in excessive amounts will reduce the amount of honey available for winter thermoregulation
and brood-rearing. A dynamic optimization model concludes that colonies should add new comb only when they have filled their
old comb with food and brood above a threshold level. The threshold increases with time until, at the end of the season, building
is never an optimal behavior. The temporal pattern of construction predicted by the model – pulses of building coincident
with periods of nectar intake and comb fullness – matches that seen in an actual colony observed over the course of an entire
foraging season. When nectar sources are rich but temporally clumped, the model also predicts that bees should be sensitive
to nectar intake, employing much higher thresholds on days when nectar is not available than on days when it is. Even under
poorer and more dispersed nectar regimes, little fitness cost is paid by colonies replacing the optimal strategy with a simpler
rule of thumb calling for new construction only when two conditions are met: (1) a fullness threshold has been exceeded, and
(2) nectar is currently being collected. Experiments demonstrate that colonies do in fact use such a rule of thumb to control
the onset of construction. However, once they have begun building, the bees continue as long as nectar collection persists,
regardless of changes in comb fullness. Thus the onset and duration of comb-building bouts appear to be under partially independent
control.
Received: 30 October 1998 / Received in revised form: 14 December 1998 / Accepted: 16 January 1999 相似文献