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1.
Environmental data quality improvement continues to focus on analytical laboratoryperformance with little, if any, attention given to improving the performance of field consultants responsible for sample collection. Many environmental professionals often assume that the primary opportunity for data error lies within the activities conducted by the laboratory. Experience in the evaluation of environmental data and project-wide quality assurance programs indicates that an often-ignored factor affecting environmental data quality is the manner in which a sample is acquired and handled in the field. If a sample is not properly collected, preserved, stored, and transported in the field, even the best laboratory practices and analytical methods cannot deliver accurate and reliable data (i.e., bad data in equals bad data out). Poor quality environmental data may result in inappropriate decisions regarding site characterization and remedial action. Field auditing is becoming an often-employed technique for examining the performance of the environmental sampling field team and how their performance may affect data quality. The field audits typically focus on: (1) verifying that field consultants adhere to project control documents (e.g., Work Plans and Standard Operating Procedures [SOPs]) during field operations; (2) providing third-party independent assurance that field procedures, quality assurance/ quality control (QA/QC)protocol, and field documentation are sufficient to produce data of satisfactory quality; (3) providing a defense in the event that field procedures are called into question; and (4) identifying ways to reduce sampling costs. Field audits are typically most effective when performed on a surprise basis; that is, the sampling contractor may be aware that a field audit will be conducted during some phase of sampling activities but is not informed of the specific day(s) that the audit will be conducted. The audit also should be conducted early on in the sampling program such that deficiencies noted during the audit can be addressed before the majority of field activities have been completed. A second audit should be performed as a follow-up to confirm that the recommended changes have been implemented. A field auditor is assigned to the project by matching, as closely as possible, the auditor's experience with the type of field activities being conducted. The auditor uses a project-specific field audit checklist developed from key information contained in project control documents. Completion of the extensive audit checklist during the audit focuses the auditor on evaluating each aspect of field activities being performed. Rather than examine field team performance after sampling, a field auditor can do so while the samples are being collected and can apply real-time corrective action as appropriate. As a result of field audits, responsible parties often observe vast improvements in their consultant's field procedures and, consequently, receive more reliable and representative field data at a lower cost. The cost savings and improved data quality that result from properly completed field audits make the field auditing process both cost-effective and functional.  相似文献   

2.
A failure to adapt to novel or changing environmental demands is a core feature of a wide variety of neuropsychiatric disorders as well as the normal states of stress and fatigue. We review the neurochemistry of cognitive control, which has been associated primarily with the prefrontal cortex. Many drugs affect the functioning of the prefrontal cortex, but the direction and extent of drug effects vary across individuals and tasks. Apparently paradoxical effects are often observed, where the same medication causes both cognitive enhancement as well as cognitive side effects. We review neurobiological research that is beginning to elucidate the nature of these contrasting effects and the factors underlying the large variability across individuals and behaviours. The work has considerable implications for the understanding of and treatment development for abnormalities such as Parkinson's disease, attention deficit hyperactivity disorder and drug addiction.  相似文献   

3.
Home injury is thought to constitute a major health burden in most developed countries. However, efforts to address this burden have been hampered by reluctance from outside agencies to interfere with the home environment of individuals, even if it benefits the occupant's safety. This paper outlines cost–benefit evaluation methods established in the transport safety domain applied to home safety to estimate the social cost of unintentional home injury in New Zealand. Estimates of costs imposed on society by home injury can provide an important motivator for initiating research and programmes to reduce home injury risk. Data sources used included mortality data, hospitalisation data and data on minor injuries that required medical treatment, but not hospital admission. We estimated that unintentional home injuries in New Zealand impose an annual social cost of about $NZ 13 billion (about $US 9 billion), which is about 3.5 times the annual social cost of road injury. These estimates provide a rational evidence base for decisions on housing-focused safety regulation or interventions that always carry some cost, and therefore need to be weighed against the benefits of injuries potentially prevented.  相似文献   

4.
Environmental accounting techniques are intended to capture important environmental costs and benefits that are often overlooked in standard accounting practices. Environmental accounting methods themselves often ignore or inadequately represent large but highly uncertain environmental costs and costs conditioned by specific prior events. Use of a predictive Bayesian model is demonstrated for the assessment of such highly uncertain environmental and contingent costs. The predictive Bayesian approach presented generates probability distributions for the quantity of interest (rather than parameters thereof). A spreadsheet implementation of a previously proposed predictive Bayesian model, extended to represent contingent costs, is described and used to evaluate whether a firm should undertake an accelerated phase-out of its PCB containing transformers. Variability and uncertainty (due to lack of information) in transformer accident frequency and severity are assessed simultaneously using a combination of historical accident data, engineering model-based cost estimates, and subjective judgement. Model results are compared using several different risk measures. Use of the model for incorporation of environmental risk management into a company's overall risk management strategy is discussed.  相似文献   

5.
The digital economy has been defined in the economic literature as one with near zero marginal cost, unmonetized services but also an escalating data flow. After a careful review of the most recent economic papers, we offer an alternative theory on the cost of privacy and data protection regulations. We have observed that the characteristics of the regulation lead not only to the amplification of costs that have been traditionally assigned as variable costs by the literature, but also of costs that used to be fixed but have been outsourced in the digital economy, meaning that significant new variable costs might trigger diseconomies of scale. At the same time, privacy and data protection regulations have created incentives that are making the dominant firms insource, in what seems to be a way back to increased sunk fixed costs for these firms. Having all that in mind, we claim that the perception of deterrence and compliance costs has affected how firms might decide to incur higher risks to avoid costs. Although compliance costs are high, we claim that an efficient implementation of the regulation avoids much of these costs. Our claim is supported by evidence that a relevant share of the regulatory costs are now variable costs, leaving room for at least two efficient strategies that medium-sized firms might implement in order to avoid them. First, firms can lower the volumes of data that they use without significantly impairing the predictive functions of their algorithms. Second, firms can invest in security at a comparatively lower degree than dominant firms considering their lower exposure to strong regulatory action.  相似文献   

6.
Moulded pulp has been used as an alternative to plastic in certain packaging applications, but some problems in the production system lead to higher costs including energy consumption. Industry tends to operate on the basis of experience rather than through scientific evaluation and systematic design methods. The research aims at detecting the problems in the production system by a multidimensional life cycle assessment (MLCA) with transparent analysis. The MLCA measures the performance of the moulded pulp production system with regard to technical, economic and environmental aspects and produces quantitative results (in monetary units), and finally indicates the overall efficiency of the production system using a sustainability index (SI). A life cycle impact assessment method based on endpoint modelling (LIME) is mainly adopted in the MLCA. Three existing moulded pulp production systems for industrial packaging in China were assessed in this study. The results show that the main environmental impacts of the three production systems are the atmospheric emissions and landfill waste; the drying stage in the production systems, which is dominated by consumption of resources and environmental impacts, is the key to controlling costs; steam should be the first preferred heat source in the drying process for achieving sustainability in the moulded pulp production system. The optimum for the three cases is identified by calculating the newly developed SI. The MLCA approach can be used to assist in identifying potential improvements and practical new packaging designs. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

7.
8.
电热水器产品逐渐成为日常生活不可或缺的家用电器,但电热水器产品的质量安全伤害事故时常发生,其产品安全受到消费者的深度关注。本文从伤害案例、监督抽查数据及重点指标3个方面,综合分析了我国电热水器产品存在的主要问题及原因,建议从加强监管力度、专业安装队伍管理及重视维护保养等方面入手,保障消费者人身安全。  相似文献   

9.
The implementation of ISO 14000 certification in a company involves a set of costs and benefits that must be known in order to assess the investment effectively in terms of environmental quality. However, as will be shown, these figures can be difficult to calculate, mainly because of a lack of reference data or specific assessment criteria. Moreover, few companies have so far implemented an Environmental Management System. Investments in environment quality sometimes simply look like costs, but benefits do exist and these are often economically quantifiable. Such benefits depend on the choice and the pursuit of aims, on the respect of rules (e.g. no omissions) and on environmental efficiency (e.g. no waste), and can only be calculated following an in-depth analysis of the system. A first and approximate estimate of these costs and benefits has been obtained for a number of real industrial cases, mainly in the chemical field, and the survey results are given in this paper. The research was carried out in Italy in companies implementing an Environmental Management System in most cases in accordance with the ISO 14000 series.  相似文献   

10.
Long-combination vehicles (LCVs) have significant potential to increase economic productivity for shippers and carriers by decreasing the number of truck trips, thus reducing costs. However, size and weight regulations, triggered by safety concerns and, in some cases, infrastructure investment concerns, have prevented large-scale adoption of such vehicles. Information on actual crash performance is needed. To this end, this work uses standard and heteroskedastic ordered probit models, along with the United States’ Large Truck Crash Causation Study, General Estimates System, and Vehicle Inventory and Use Survey data sets, to study the impact of vehicle, occupant, driver, and environmental characteristics on injury outcomes for those involved in crashes with heavy-duty trucks. Results suggest that the likelihood of fatalities and severe injury is estimated to rise with the number of trailers, but fall with the truck length and gross vehicle weight rating (GVWR). While findings suggest that fatality likelihood for two-trailer LCVs is higher than that of single-trailer non-LCVs and other trucks, controlling for exposure risk suggest that total crash costs of LCVs are lower (per vehicle-mile traveled) than those of other trucks.  相似文献   

11.
12.
The repair and regeneration of large bone defects resulting from disease or trauma remains a significant clinical challenge. Bioactive glass has appealing characteristics as a scaffold material for bone tissue engineering, but the application of glass scaffolds for the repair of load-bearing bone defects is often limited by their low mechanical strength and fracture toughness. This paper provides an overview of recent developments in the fabrication and mechanical properties of bioactive glass scaffolds. The review reveals the fact that mechanical strength is not a real limiting factor in the use of bioactive glass scaffolds for bone repair, an observation not often recognized by most researchers and clinicians. Scaffolds with compressive strengths comparable to those of trabecular and cortical bones have been produced by a variety of methods. The current limitations of bioactive glass scaffolds include their low fracture toughness (low resistance to fracture) and limited mechanical reliability, which have so far received little attention. Future research directions should include the development of strong and tough bioactive glass scaffolds, and their evaluation in unloaded and load-bearing bone defects in animal models.  相似文献   

13.
The epidemiology and prevention of child pedestrian injury   总被引:7,自引:1,他引:6  
Of pedestrian injuries that occur every year, approximately 50,000, including 1300 fatalities, are experienced by children between the ages of 1 and 14 years. Despite the importance of the problem, the pedestrian safety issue is often neglected in reports on vehicular injuries. Children between the ages of five and nine years, boys, and children in lower socioeconomic class are at higher risk of pedestrian injury than other children. Childhood pedestrian injuries take place predominantly in residential locations close to home and frequently occur while the child is at play. The risk of pedestrian injury to children is higher than that of other age groups when adjusted for traffic exposure, and a variety of developmental limitations may account for this fact. In spite of these limitations, children undertake collision avoidance maneuvers far more often than drivers do. Accident analyses have identified 15 different accident types, each reflecting a unique combination of human and environmental factors. Among children, the most frequently observed accident type is the midblock dart-out. Programs to modify pedestrian behavior, driver behavior, and vehicle design have met with modest success. In the United States, the cultural and political environments have not been favorable to the injury prevention effort. Urban designers and traffic engineers in Europe have undertaken a variety of modifications of the physical environment, and some of these have been successful in preventing pedestrian injuries to children.  相似文献   

14.
Case control studies suggest that cycle helmets offer their wearers protection from injury in the event of an accident. Nevertheless, encouragement and even compulsion of cycle helmet wearing has been controversial. This paper will re-examine another potential source of evidence for the role of cycle helmets. Administrative datasets are attractive because of their availability, but require careful analysis. The results presented here are obtained from analysing such data with an appropriate form of generalised additive model. Whilst helmet wearing surveys in the UK suggest strongly divergent trends in wearing rates between male and female children, there is little evidence from "Hospital Episode Statistics" to indicate similarly divergent trends in terms of head injury. Conversely, it can be confirmed that head injuries are falling faster among cyclists than pedestrians. Although case control studies suggest cycle helmets are not effective in reducing overall injuries, it is worth noting an increase in the proportion of male child cyclists reported by the police as being killed or seriously injured in road collisions. It might be tempting to use these results to suggest that helmets are not effective in reducing head injury at the population level. Whilst the careful analysis of population level data presented here is clearly important, this paper will discuss the reasons why population and individual level analyses of cycle helmets might be different and consider some of the difficulties in assigning cause and effect with imperfect observational data.  相似文献   

15.
Acute kidney injury is commonly encountered in critically ill patients, and is associated with worse outcomes. Fluid therapy is a key component in the management of these patients, often leading to fluid overload, especially in the setting of septic acute kidney injury. Emerging data overwhelmingly suggest that fluid overload in these patients may be associated with adverse outcomes. Management of such patients should include a strategy of early guided resuscitation, followed by careful assessment of fluid status, and early initiation of renal replacement therapy as soon as it is deemed safe, aiming for a neutral or negative fluid balance. This review will focus on the pathophysiological link between fluid overload and acute kidney injury, mechanisms of organ dysfunction in fluid overload, and strategies for management.  相似文献   

16.
Studies about supply chain coordination have emphasised maximising the profit of the overall supply chain, but the profit changes of individual members in the supply chain have often been overlooked. It has been shown that profit increment of the whole supply chain may not be beneficial for every individual member. Therefore, the use of quantity discounts to achieve the coordination of a supply chain is discussed in this article. A two-echelon selling system with a single buyer and multiple suppliers is considered to enhance profitability for both sides at the same time. An acceptable quantity discount condition for both the buyer and the suppliers to determine an appropriate order quantity allocation to produce more profits in the supply chain is proposed. Furthermore, the profit distribution between the buyer and each supplier is studied. Finally, the results of the numerical application show that the buyer should focus on managing the procurement costs to decrease the acquiring costs, and the suppliers should focus on the fixed costs of management to reduce the production costs in machine operations.  相似文献   

17.
ABSTRACT

There is a recognized need to advance cumulative effects assessment to regional and ecologically meaningful scales, but such initiatives are often critiqued for being isolated from management contexts and the regulatory practices of project-based environmental assessment. A major challenge is that there has been limited attention devoted to understanding decision-making at the project level, and the value of monitoring data to support cumulative effects analysis. This article examines how cumulative effects are considered during environmental assessment decision-making within the context of freshwater management in the Mackenzie Valley, Northwest Territories. Interviews with representatives from organizations involved in environmental assessment, regulation, and monitoring are used to identify challenges to applying information about cumulative effects at the project scale. Results reinforce the need for regional approaches and improvements in information and monitoring capacities to support cumulative effects analysis, but also the need to address institutional and organizational deficiencies to ensure that the data and information generated are useful to and applied within project-based decision-making.  相似文献   

18.
Although previous research suggests that safety benefits accrue from periodic vehicle inspection programmes, little consideration has been given to whether the benefits are sufficient to justify the often considerable costs of such schemes. Methodological barriers impede many attempts to evaluate the overall safety benefits of periodic vehicle inspection schemes, including this study, which did not attempt to evaluate the New Zealand warrant of fitness scheme as a whole. Instead, this study evaluated one aspect of the scheme: the effects of doubling the inspection frequency, from annual to biannual, when the vehicle reaches six years of age. In particular, reductions in safety-related vehicle faults were estimated together with the value of the safety benefits compared to the costs. When merged crash data, licensing data and roadworthiness inspection data were analysed, there were estimated to be improvements in injury crash involvement rates and prevalence of safety-related faults of respectively 8% (95% CI 0.4–15%) and 13.5% (95% CI 12.8–14.2%) associated with the increase from annual to 6-monthly inspections. The wide confidence interval for the drop in crash rate shows considerably statistical uncertainty about the precise size of the drop. Even assuming that this proportion of vehicle faults prevented by doubling the inspection frequency could be maintained over the vehicle age range 7–20 years, the safety benefits are very unlikely to exceed the additional costs of the 6-monthly inspections to the motorists, valued at $NZ 500 million annually excluding the overall costs of administering the scheme. The New Zealand warrant of fitness scheme as a whole cannot be robustly evaluated using the analysis approach used here, but the safety benefits would need to be substantial – yielding an unlikely 12% reduction in injury crashes – for benefits to equal costs.  相似文献   

19.
Radio-Frequency Plasma Beam Sources — New tools for industrial particle beam induced thin film processes The applications for ion beam techniques has moved from pure base research to industry, mainly for microelectronics applications. Their potential for future surface and thin film processes are known to a large number of users and developers in this area. However such techniques are relative sophisticated and due to the costs industrial applications are often limited. RF-plasma beam technology with its specific advantages may be a possible candidate to overcome these restrictions. For some applications RF plasma beam technology is just on the step to an industrial use. But this technique is still not generally known, and its possibilities deserves more attention. Within this article the principle of plasma beam formation and construction of plasma beam formation and construction of plasma beam sources are described. Some application examples show the possibilities given to users with this technique.  相似文献   

20.
Naturally occurring asbestos: a recurring public policy challenge   总被引:1,自引:0,他引:1  
The potential environmental hazards and associated public health issues related to exposure to respirable dusts from the vicinity of natural in-place asbestos deposits (commonly referred to as naturally occurring asbestos, NOA) have gained the regulatory and media spotlight in many areas around the United States, such as Libby, MT, Fairfax County, VA, and El Dorado Hills, CA, among others. NOA deposits may be present in a variety of geologic formations. It has been suggested that airborne asbestos may be released from NOA deposits, and absent appropriate engineering controls, may pose a potential health hazard if these rocks are crushed or exposed to natural weathering and erosion or to human activities that create dust. The issue that needs to be addressed at a policy level is the method of assessing exposures to elongated rock fragments ubiquitous in dust clouds in these same environments and the associated risk. Elongated rock fragments and single crystal minerals present in NOA have been construed by some as having attributes, including the health effects, of asbestos fibers. However, the Occupational Safety and Health Administration (OSHA), Mine Safety and Health Administration (MSHA), and the Consumer Products Safety Commission (CPSC) found that the scientific evidence did not support this assumption. As in many environmental fields of study, the evidence is often disputed. Regulatory policy is not uniform on the subject of rock fragments, even within single agencies. The core of the issue is whether the risk parameters associated with exposures to commercial asbestos can or should be applied to rock fragments meeting an arbitrary set of particle dimensions used for counting asbestos fibers. Inappropriate inclusion of particles or fragments results in dilution of risk and needless expenditure of resources. On the other hand, inappropriate exclusion of particles or fragments may result in increased and unnecessary risk. Some of the fastest growing counties in the United States are in areas where NOA is known to exist and therefore this issue takes on national significance. This ongoing national dilemma has raised public and business concerns. There has been continuing political and scientific debate and widespread miscommunication over perceived versus actual health risks, the validity of various analytical sampling and testing methods, the questionable necessity and escalating costs of remediation procedures, and the combined negative impact on numerous commercial and public interests. Thus, conflicting research and regulatory positions on the distinctions between and hazards of true asbestos and ordinary rock fragments is all that is presently available to the public until the differing scientific communities and government agencies arrive at a consensus on these issues. The risk assessment methodology and the analytical technology needed to support inferences drawn from existing research are available, but have not been organized and implemented in the manner needed to resolve the NOA controversy. There should exist nationally adopted and peer-reviewed NOA standards (developed jointly by the scientific community, health risk professionals, and government regulators) that establish: (1) a scientific basis for risk evaluation and assessment of NOA and rock fragments; (2) accepted analytical protocols for determining if NOA actually exists in a given area and for separating NOA from related non-asbestos rock fragments and single crystal minerals; and (3) effective public policies for managing NOA, minimizing potential hazards, and protecting public health. This article will review some of the key issues involved with the current NOA debate, propose improved analytical methodologies, describe potential solutions for dealing with NOA, and outline the benefits to be gained by creating a practical national NOA public policy.  相似文献   

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