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排序方式: 共有419条查询结果,搜索用时 31 毫秒
401.
A study of a small sample of construction fatal accidents was used to pilot a potential method of analysis for the UK Health and Safety Executive (HSE) Construction Division. The work was conducted in the context of a Governmental Inquiry into construction fatalities in 2009, but has been developed further since. The sample of 26 accidents (28 fatalities) was drawn from the 211 fatal accidents in the years ending 2006–2008, to be broadly illustrative of the range of accident characteristics. The accidents were analysed on the basis of available inspectorate reports and structured interviews with the investigating inspectors. A standard method of classification on four levels was developed, based on the Human Factors Analysis and Classification System (HFACS) classification of errors and task level factors, with additional categories covering the organisational and regulatory/market levels of the system. The results showed a concentration of underlying factors associated with inadequacies in planning and risk assessment, competence assurance, hardware design, purchase and installation, and contracting strategy. These findings were partially validated by comparing them with another sample of 50 accidents analysed earlier by the HSE. This paper describes the development and testing of the investigation and classification method and how it is being further developed since the initial study. It also provides a summary of the findings relating to underlying causes.  相似文献   
402.
Acoustic telemetry was used to track vertical and horizontal movement patterns and to monitor the stomach temperatures of seven juvenile shortfin mako sharks (Isurus oxyrinchus Rafinesque) in the Southern California Bight from July to November 2002. Makos (80–145 cm fork length, FL) were attracted to the tracking vessel, where they were fed a mackerel containing an acoustic transmitter that reported temperature and pressure. Tracks ranged from 6.8–45.4 h. Collectively, the mako sharks spent 80% of the track record at 0–12 m, 15% at 12–24 m, and 5% at depths >24 m. The average horizontal swimming speed was 2.3 km h–1 or 0.55 FLs s–1, and the greatest distance traveled was 145 km in 45.4 h. For the six tracks >21 h, there was a positive correlation between body size and maximum depth. Makos used more of the water column during daylight hours. Mean stomach temperature was 3.8±1.5°C above ambient, and body size was positively correlated with both maximum and average stomach temperature. Stomach content analyses of four makos captured at the end of tracking verified the occurrence of feeding events as indicated by changes in stomach temperature.Electronic Supplementary Material Supplementary material is available in the online version of this article at Communicated by J.P. Grassle, New Brunswick  相似文献   
403.
Birthing Sphere     
Walker P  Purdin S 《Disasters》2004,28(2):100-111
This paper tells the story of the initiation and first year of Sphere. It traces the history of how the project was started and its relationship to other major events of that time, principally the multi-donor Rwanda evaluation. The paper describes how the basic structure of the Sphere standards was agreed upon and discusses why some sectors were eventually left out of the standards. Tensions and public disagreements between the agencies that created Sphere are discussed, along with the manner in which the chosen working processes contributed to the successful publication of the Sphere standards. We show how the process of policy formulation, which led up to the publication of the first edition of the Sphere standards, was as dependent upon the ability of the project team to work opportunistically as it was upon the application of agency principles. Finally the paper reflects upon the success of Sphere and lessons that can be learned from this early Sphere process.  相似文献   
404.
In this paper, a field study was carried out to examine the effect of flue gas desulfurization (FGD) by-product on water quality at an underground coal mine in central-eastern Ohio. Flue gas desulfurizalion by-product was injected into the down-dip portions of the Robert-Dawson mine in an attempt to seal major seeps exiting the mine and to coat exposed pyritic surfaces. Immediately following grout injection, significant increases in acidity, iron, aluminum, sulfur, and calcium were observed at most surface and ground water locations near where grouting was carried out. Following this initial flush of elements, concentrations of most constituents have decreased to near pre-grouting levels. Data from the site and geochemical modeling suggest that an increase in water level or rerouting of drainage flow resulted in the dissolution of iron and aluminum sulfate salts and ferrihydrite. Dissolution of the FGD grout material resulted in increases in calcium and sulfate concentrations in the drainage waters. Water within the mine voids was saturated with respect to calcium sulfate and gypsum immediately following grout injection. Based on an analysis of core samples obtained from the site, acid mine drainage (AMD) was in contact with at least some portions of the grout and this resulted in grout weathering. Subsequent transport of calcium and sulfate to the underclay, perhaps by fracture flow, has resulted in the deposition of gypsum and calcium sulfate solids.  相似文献   
405.
In order to prevent salinisation of the streams of the Riverine Plain of the Murray-Darling Basin in southern Australia, evaporation basins are used to dispose of saline irrigation drainage water. Local on-farm (individual landholder) and community (shared between multiple landholders) basins are increasingly being used to prevent export of salt outside irrigation districts. There are questions regarding the availability of land suitable for these basins and their impact on the surrounding environment. We describe the use of currently available spatial data to assist in regional planning for the environmentally safe use of these basins. A GIS-based approach was developed using suitability criteria expected to minimise the risk of off-site effects of basin leakage. The criteria were proximity to surface water features, urban areas and infrastructure, water table depth and salinity, and soil hydraulic conductivity. The approach was applied to all of the major irrigation districts at 1:250,000, the scale at which data are available over the entire Riverine Plain. Confidence in well-defined parameters such as proximity to infrastructure, urban areas and surface water features was higher than for those involving interpolated point data such as water table depth, salinity, and hydraulic conductivity. Most critically, hydraulic conductivity, the most important factor for basin leakage, was found to be unreliable at this scale. Use of higher resolution data (up to 1:100,000) available for two of the irrigation districts improved confidence in both water table depth and salinity but not in hydraulic conductivity. Despite these limitations, it was found that: (i) on-farm basins can only be used on an opportunistic basis in the eastern irrigation districts, but can be widely used in the western districts; (ii) community basins can be used anywhere there is suitable land; and (iii) the results raise serious questions as to whether there is enough suitable land in the eastern districts to dispose of all of the drainage water that is produced.  相似文献   
406.
Adopting a new paradigm for natural resource and environmental policy that emphasises continuous change, adaptation and learning demands a new approach to evaluation to enable improvements in the way these initiatives contribute to sustainable resource use. Evaluation is fundamental to identifying change, supporting an adaptive approach that is flexible enough to meet the challenge of change, and enabling learning at individual, community, institutional and policy levels. Based on a consideration of changing approaches to natural resource management (NRM) policy and observations and experiences in the practical assessment of on-the-ground initiatives, the authors develop a set of principles for evaluation in NRM that: (a) addresses evaluation from a systems perspective, (b) links objective to consequence, (c) considers the fundamental assumptions and hypotheses that underpin core policy or program objectives, (d) is grounded in the natural resource, policy/institutional, economic, socio-cultural and technological contexts of implementation in practice, (e) establishes practical and valid evaluation criteria by which change can be monitored and assessed, (f) involves methodological pluralism including both quantitative and qualitative methods to ensure rigour and comprehensiveness in assessment, and (g) integrates different disciplinary perspectives (i.e. social, economic, environmental, policy and technological). The paper develops a systems-based evaluation framework that incorporates these principles and also recognises the multiple levels and nested nature of NRM policy, namely: problem characterisation, policy formulation and intent, program logic, and on-ground implementation. Finally, we demonstrate its utility through application to three contrasting Australian case studies: a community-based Integrated Catchment Management policy implementation; a resource information delivery system; and the development of a Decision Support System.  相似文献   
407.
To identify sources of nutrition potentially available to the yolk-deficient embryos of the brooding brittlestar Amphipholis squamata Della Chiaje, (= Axiognathus squamata, Thomas 1966), specimens were collected intertidally at all seasons (1986 through 1987) from Odiorne Point, Rye, New Hampshire and from Appledore Island, Isles of Shoals, Maine, USA. Ultrastructural, autoradiographic and immunohistochemical studies were made of adults and brooded embryos. Adult and embryonic tissues have morphological adaptations which support healthy, symbiotic bacteria (5 to 9 x 106 colony forming units/adult brittlestar), while autoradiographic studies indicate direct uptake of labeled amino acids by eukaryotic host tissues and bacteria. Cell envelopes of subcuticular bacteria suggest that they are Gram negative and may belong in the genus Vibrio. Based on immunohistochemical localization, it appears that a single type of bacterium is present in large numbers under the cuticles of embryos and adults of A. squamata. This is the first study of the relationship between an echinoderm and a bacterium which includes isolation and immunohistochemical verification of the identity of the bacterial symbiont.  相似文献   
408.
409.
Our study investigated applicant characteristics in response to organizations incorporating an affirmative action policy (AAP) statement in recruitment material. Study participants (N = 217; White upper‐level management students) randomly received recruitment material containing one of three statements (e.g., affirmative action, equal employment opportunity (EEO), or no statement regarding affirmative action or EEO) and were asked to evaluate the attractiveness of the organization publicizing the designated policy. Results indicated that individuals responded negatively to AAPs in recruitment material because of prejudice attitudes, the perceived unfairness of such programs (which we relate to equity sensitivity), or in an attempt to protect their own self‐interest (which we relate to general self‐efficacy). Additionally, individuals' equity sensitivity and general self‐efficacy both moderated the relationship between racial prejudice and organizational attractiveness. Specifically, the negative relationships between participants' prejudice attitudes and the attractiveness of organizations publicizing an affirmative action policy were stronger for benevolents (persons tolerant of situations where they are under‐rewarded) and for persons low in self‐efficacy. Implications of our findings for organizational recruitment practices are discussed. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
410.
In the last 10 years, research devoted to the construct of leader–member exchange (LMX) has increasingly relied on the tenets of social exchange as a theoretical foundation to propose and test relationships between supervisor‐subordinate dyads and variables of significant consequence. Despite the theory underpinning such relationships, researchers continue to measure LMX with scales developed to assess vertical dyad linkage (VDL), not social exchange. To address this concern, we investigated the content validity of LMX7 (the most widely cited measure of LMX) and LMX‐MDM (a popular multidimensional measure of LMX). Findings from content validity assessments by 25 LMX experts revealed LMX7 and LMX‐MDM items are not representative of the construct of social exchange. As such, we undertook a series of studies to develop a new scale we label, leader–member social exchange (LMSX). Results indicate LMSX is able to assess different, as well as the same, components of the supervisor–subordinate relationship as previous scales while being more theoretically consistent with the notion of social exchange. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
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