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391.
392.
BACKGROUND: Safety teams have become a popular means to recognize and prevent injuries in the workplace. In fact, organizations, such as OSHA, NIOSH, NIEHS, DOE, and the Ohio BWC, not only encourage safety teams, but have implemented them in their organizations. However, safety teams may not be legal as defined by NLRB Act Sections 2(5) and 8(a)(2). OBJECTIVE: To determine whether safety teams are illegal labor organizations. METHODS: A review of government regulations, safety programs, and safety teams was performed to create a framework of what types of safety programs/regulations are requested and/or required by a variety of government agencies. Next, these requirements were compared to existing case law on illegal labor organizations as defined by the NLRB. RESULTS: Most safety teams and programs, even those implemented by the Federal Government, are illegal labor organizations as defined by NLRB Act Sections 2(5) and 8(a)(2). CONCLUSIONS: The Federal Government needs to amend existing legislation and develop a revision of the NLRB Act that would allow safety teams to function legally in organizations without having to meet intrusive, constricting guidelines that may inhibit the value of safety teams. IMPACT ON INDUSTRY: Organizations must be aware that safety teams may be valuable in reducing job-related accidents and injuries but they may be illegal labor organizations. 相似文献
393.
An analysis of motorcycle injury and vehicle damage severity using ordered probit models 总被引:7,自引:0,他引:7
Problem: Motorcycles constitute about 19% of all motorized vehicles in Singapore and are generally overrepresented in traffic accidents, accounting for 40% of total fatalities. Method: In this paper, an ordered probit model is used to examine factors that affect the injury severity of motorcycle accidents and the severity of damage to the vehicle for those crashes. Nine years of motorcycle accident data were obtained for Singapore through police reports. These data included categorical assessments of the severity of accidents based on three levels. Damage severity to the vehicle was also assessed and categorized into four levels. Categorical data of this type are best analyzed using ordered probit models because they require no assumptions regarding the ordinality of the dependent variable, which in this case is the severity score. Various models are examined to determine what factors are related to increased injury and damage severity of motorcycle accidents. Results: Factors found to lead to increases in the probability of severe injuries include the motorcyclist having non-Singaporean nationality, increased engine capacity, headlight not turned on during daytime, collisions with pedestrians and stationary objects, driving during early morning hours, having a pillion passenger, and when the motorcyclist is determined to be at fault for the accident. Factors leading to increased probability of vehicle damage include some similar factors but also show some differences, such as less damage associated with pedestrian collisions and with female drivers. In addition, it was also found that both injury severity and vehicle damage severity levels are decreasing over time. 相似文献
394.
The hydrogeomorphic (HGM) approach to wetland classification and functional assessment is becoming more widespread in the
United States but its use has been limited by the length of time needed to develop appropriate data sets and functional assessment
models. One particularly difficult aspect is the transferability among geographic regions of specific models used to assess
wetland function. Sharing of models could considerably shorten development and implementation of HGM throughout the United
States and elsewhere. As hydrology is the driving force behind wetland functions, we assessed the comparability of hydrologic
characteristics of three HGM subclasses (slope, headwater floodplain, mainstem floodplain) using comparable long-term hydrologic
data sets from different regions of the United States (Ridge and Valley Province in Pennsylvania and the Willamette Valley
in Oregon). If hydrology by HGM subclass were similar between different geographic regions, it might be possible to more readily
transfer extant models between those regions. We found that slope wetlands (typically groundwater-driven) had similar hydrologic
characteristics, even though absolute details (such as depth of water) differed. We did not find the floodplain subclasses
to be comparable, likely due to effects of urbanization in Oregon, regional differences in soils and, perhaps, climate. Slight
differences in hydrology can shift wetland functions from those mediated by aerobic processes to those dominated by anaerobic
processes. Functions such as nutrient cycling can be noticeably altered as a result. Our data suggest considerable caution
in the application of models outside of the region for which they were developed. 相似文献
395.
Human impacts on the stream-groundwater exchange zone 总被引:13,自引:0,他引:13
Hancock PJ 《Environmental management》2002,29(6):763-781
Active exchanges of water and dissolved material between the stream and groundwater in many porous sand- and gravel-bed rivers
create a dynamic ecotone called the hyporheic zone. Because it lies between two heavily exploited freshwater resources—rivers
and groundwater—the hyporheic zone is vulnerable to impacts coming to it through both of these habitats. This review focuses
on the direct and indirect effects of human activity on ecosystem functions of the hyporheic zone. River regulation, mining,
agriculture, urban, and industrial activities all have the potential to impair interstitial bacterial and invertebrate biota
and disrupt the hydrological connections between the hyporheic zone and stream, groundwater, riparian, and floodplain ecosystems.
Until recently, our scientific ignorance of hyporheic processes has perhaps excused the inclusion of this ecotone in river
management policy. However, this no longer is the case as we become increasingly aware of the central role that the hyporheic
zone plays in the maintenance of water quality and as a habitat and refuge for fauna. To fully understand the impacts of human
activity on the hyporheic zone, river managers need to work with scientists to conduct long-term studies over large stretches
of river. River rehabilitation and protection strategies need to prevent the degradation of linkages between the hyporheic
zone and surrounding habitats while ensuring that it remains isolated from toxicants. Strategies that prevent anthropogenic
restriction of exchanges may include the periodic release of environmental flows to flush silt and reoxygenate sediments,
maintenance of riparian buffers, effective land use practices, and suitable groundwater and surface water extraction policies. 相似文献
396.
Three mathematical models, the runoff curve number equation, the universal soil loss equation, and the mass response functions,
were evaluated for predicting nonpoint source nutrient loading from agricultural watersheds of the Mediterranean region. These
methodologies were applied to a catchment, the gulf of Gera Basin, that is a typical terrestrial ecosystem of the islands
of the Aegean archipelago. The calibration of the model parameters was based on data from experimental plots from which edge-of-field
losses of sediment, water runoff, and nutrients were measured. Special emphasis was given to the transport of dissolved and
solid-phase nutrients from their sources in the farmers' fields to the outlet of the watershed in order to estimate respective
attenuation rates. It was found that nonpoint nutrient loading due to surface losses was high during winter, the contribution
being between 50% and 80% of the total annual nutrient losses from the terrestrial ecosystem. The good fit between simulated
and experimental data supports the view that these modeling procedures should be considered as reliable and effective methodological
tools in Mediterranean areas for evaluating potential control measures, such as management practices for soil and water conservation
and changes in land uses, aimed at diminishing soil loss and nutrient delivery to surface waters. Furthermore, the modifications
of the general mathematical formulations and the experimental values of the model parameters provided by the study can be
used in further application of these methodologies in watersheds with similar characteristics. 相似文献
397.
Huntington HP Brown-Schwalenberg PK Frost KJ Fernandez-Gimenez M Norton DW Rosenberg DH 《Environmental management》2002,30(6):0778-0792
Traditional ecological knowledge (TEK) and the information and insights it offers to natural resource research and management
have been given much attention in recent years. On the practical question of how TEK is accessed and used together with scientific
knowledge, most work to date has examined documentation and methods of recording and disseminating information. Relatively
little has been done regarding exchanges between scientific and traditional knowledge. This paper examines three workshop
settings in which such exchanges were intended outcomes. The Barrow Symposium on Sea Ice, the Exxon Valdez Oil Spill Restoration Program Synthesis/Information Workshops, and the Alaska Beluga Whale Committee illuminate certain features
of the preparation, format, and context of workshops or series of workshops and their eventual outcomes and influence. The
examples show the importance of long-term relationships among participants and thorough preparation before the actual workshop.
Further research should look more systematically at the factors that influence the success of a given workshop and the various
ways in which participants perceive success. 相似文献
398.
River systems as providers of goods and services: a basis for comparing desired and undesired effects of large dam projects 总被引:3,自引:0,他引:3
Brismar A 《Environmental management》2002,29(5):598-609
In developing countries, large dam projects continue to be launched, primarily to secure a time-stable freshwater supply and
to generate hydropower. Meanwhile, calls for environmentally sustainable development put pressure on the dam-building industry
to integrate ecological concerns in project planning and decision-making. Such integration requires environmental impact statements
(EISs) that can communicate the societal implications of the ecological effects in terms that are understandable and useful
to planners and decision-makers.
The purpose of this study is to develop a basic framework for assessing the societal implications of the river ecological
effects expected of a proposed large dam project. The aim is to facilitate a comparison of desired and potential undesired
effects on-site and downstream. The study involves two main tasks: to identify key river goods and services that a river system
may provide, and to analyze how the implementation of a large dam project may alter the on-site capacity and downstream potentials
to derive river goods and services from the river system.
Three river goods and six river services are identified. River goods are defined as extractable partly man-made products and
river services as naturally sustained processes. By four main types of flow manipulations, a large dam project improves the
on-site capacity to derive desired river goods, but simultaneously threatens the provision of desirable river goods and services
downstream. However, by adjusting the site, design, and operational schedule of the proposed dam project, undesirable effects
on river goods and services can be minimized. 相似文献
399.
This paper describes a fuzzy hierarchical analytic approach to determine the weighting of subjective judgments. In addition,
it presents a nonadditive fuzzy integral technique to evaluate a green engineering industry case as a fuzzy multicriteria
decision-making (FMCDM) problem. When the investment strategies are evaluated from various aspects, such as economic effectiveness,
technical feasibility, and environmental regulation, it can be regarded as an FMCDM problem. Since stakeholders cannot clearly
estimate each considered criterion in terms of numerical values for the anticipated alternatives/strategies, fuzziness is
considered to be applicable. Consequently, this paper uses triangular fuzzy numbers to establish weights and anticipated achievement
values. By ranking fuzzy weights and fuzzy synthetic utility values, we can determine the relative importance of criteria
and decide the best strategies. This paper applies what is called a λ fuzzy measure and nonadditive fuzzy integral technique
to evaluate the synthetic performance of green engineering strategies for aquatic products processors in Taiwan. In addition,
we demonstrate that the nonadditive fuzzy integral is an effective evaluation and appears to be appropriate, especially when
the criteria are not independent. 相似文献
400.
Only a few empirical studies on forest aesthetics have adopted a water-based perspective for observers and have investigated
the perceived visual quality of forested shorelines. In forested environments with many lakes, such as the boreal forest in
the Canadian Shield, individuals have greater exposure to forests from water-based rather than in-stand vantage points. This
study employed the psychophysical research direction to explore the relationships between scenic beauty and biophysical characteristics
of the forested shorelines in the boreal forests. Two model forms were tested. One model related the variation of shoreline
forest aesthetic evaluations of near-vista views (140 m offshore) to a set of forest mensuration data. Tree size, tree mortality,
conifer shrubs, tree density, amount of hardwood, and slope explained 60.2% of the variance in scenic beauty between the study
sites. A second model was calibrated to test the relationship between an already existing ecosystem vegetation classification
system and the aesthetic evaluations of the same forested shorelines. When the ecosystem classification was simplified to
eight groups, the model explained 48.5% of variance. These models suggest that the psychophysical approach to studying aesthetics
can be applied successfully to near-vista evaluations of scenic beauty. The finding that a forest ecosystem classification
system is highly related to scenic beauty suggests that, at least in the boreal forest, managers can reasonably estimate the
scenic beauty of forested shoreline environments from an ecosystem classification, with little need for intensive data on
these sites. 相似文献