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601.
Jun Yoshizaki Cavell Brownie Kenneth H. Pollock William A. Link 《Environmental and Ecological Statistics》2011,18(1):27-55
Misidentification of animals is potentially important when naturally existing features (natural tags) such as DNA fingerprints
(genetic tags) are used to identify individual animals. For example, when misidentification leads to multiple identities being
assigned to an animal, traditional estimators tend to overestimate population size. Accounting for misidentification in capture–recapture
models requires detailed understanding of the mechanism. Using genetic tags as an example, we outline a framework for modeling
the effect of misidentification in closed population studies when individual identification is based on natural tags that
are consistent over time (non-evolving natural tags). We first assume a single sample is obtained per animal for each capture
event, and then generalize to the case where multiple samples (such as hair or scat samples) are collected per animal per
capture occasion. We introduce methods for estimating population size and, using a simulation study, we show that our new
estimators perform well for cases with moderately high capture probabilities or high misidentification rates. In contrast,
conventional estimators can seriously overestimate population size when errors due to misidentification are ignored. 相似文献
602.
603.
604.
John S. Lagarias William W. Sylte 《Journal of the Air & Waste Management Association (1995)》2013,63(9):1176-1179
The field measurement phase of the San Joaquin Valley Air Quality Study, which was conducted in the summer of 1990, was the largest and most sophisticated study of its kind ever conducted in this country. The San Joaquin Valley has the nation’s second worst overall air quality problem and is using the study results to conduct regional modeling to refine its control strategies. The study began in 1985 and will continue into the mid-1990s. The origins of the study, and the manner in which it is being funded and administered, reflect a unique and highly successful collaboration among several levels of government and the private sector. The temporary organizational structure formed to manage the study sets an interesting precedent for how political-level leaders can work effectively with the scientific community to conduct a long term technical study. 相似文献
605.
Clyde M. Smith William E. Brown 《Journal of the Air & Waste Management Association (1995)》2013,63(7):1015-1019
Collectively, surface coating operations using paints with hydrocarbon solvents may well be the largest industrial source of volatile organic compounds (VOC) and hazardous air pollutants (HAP). Most surface coating operations involve the manual application of paint with spray equipment inside a paint spray booth. The booth exhaust system collects the solvent fumes and then exhausts them through a stack to the atmosphere. Stack emissions are characteristically high in flow rate and low in concentration. Since control equipment is sized based on exhaust flow rate rather than concentration, control of VOC and HAP requires large, expansive abatement equipment. Simple, effective designs employing recycling of air have greatly reduced the exhaust flow rate and the cost of the control equipment. However, these designs are not popular because they are burdened by various flaws, notably worker endangerment. The Mobile Zone recirculation system can be incorporated into new construction or retrofitted to existing spray booths and will reduce the exhaust volumes ranging from 65 to 95 percent without adversely affecting the production rate, production quality or worker safety. 相似文献
606.
Marjo V. Smith William F. McDonnell 《Journal of the Air & Waste Management Association (1995)》2013,63(3):289-298
ABSTRACT Lung function response to inhaled ozone at ambient air pollution levels is known to be a function of ozone concentration, exposure duration, and minute ventilation. Most data-driven exposure-response models address exposures under static condition (i.e., with a constant ozone concentration and exercise pattern). Such models are simplifications, as both ambient ozone concentrations and normal human activity patterns change with time. The purpose of this study was to develop a dynamic model of response with the advantages of a statistical model (a relatively simple structure with few parameters). A previously proposed mechanistic model for changes in specific airways resistance was adapted to describe the percent change in forced expiratory volume in one second (FEV1). This model was then reduced using the fit to three existing exposure-response data sets as criterion. The resulting model consists of a single linear differential equation together with an algebraic logistic equation. Under restricted static conditions the model reduces to a logistic model presented earlier by the authors. 相似文献
607.
Masum A. Patwary William Thomas O’Hare Graham Street K. Maudood Elahi Syed Shahadat Hossain Mosharraf H. Sarker 《Waste management (New York, N.Y.)》2009,29(8):2392-2397
There is a concern that mismanagement of medical waste in developing countries may be a significant risk factor for disease transmission. Quantitative estimation of medical waste generation is needed to estimate the potential risk and as a basis for any waste management plan. Dhaka City, the capital of Bangladesh, is an example of a major city in a developing country where there has been no rigorous estimation of medical waste generation based upon a thorough scientific study. These estimates were obtained by stringent weighing of waste in a carefully chosen, representative, sample of HCEs, including non-residential diagnostic centres. This study used a statistically designed sampling of waste generation in a broad range of Health Care Establishments (HCEs) to indicate that the amount of waste produced in Dhaka can be estimated to be 37 ± 5 ton per day. The proportion of this waste that would be classified as hazardous waste by World Health Organisation (WHO) guidelines was found to be approximately 21%. The amount of waste, and the proportion of hazardous waste, was found to vary significantly with the size and type of HCE. 相似文献
608.
William R. Pierson Alan W. Gertler Ronald L. Bradow 《Journal of the Air & Waste Management Association (1995)》2013,63(11):1495-1504
The Van Nuys Tunnel experiment conducted in 1987 by Ingalls et al. (see A&WMA Paper 89-137.3), to verify automotive emission inventories as part of the Southern California Air Quality Study (SCAQS), gave higher CO and HC emission-rate values than expected on the basis of automotive-emission models—by factors of approximately 3 and 4, respectively. The CO/NOX and HC/NOX emission-rate ratios moreover were higher than expected—by similar factors (NOX emission rates were about as expected). The purpose of the present paper is to review the literature on dynamometer and on-road (in tunnels and along roadways) testing of in-use vehicles, and on urban-air CO/HC/NOX concentration ratios, to see whether the Van Nuys Tunnel results are reasonable in terms of previous experience. The conclusions are that (1) on-road CO and HC emissions higher than expected have been reported before, (2) on-road CO and HC emissions consistent with the Van Nuys Tunnel results have been reported before, and (3) on-road CO/NOX and HC/NOX emission-rate ratios higher than expected have been reported before. The Van Nuys Tunnel NOX results actually are lower than in other on-road experiments, and the CO/NOX and HC/NOX ratios consequently are higher. The higher-than-predicted CO/NOX and HC/NOX ratios at Van Nuys and other on-road sites suggest richer operation on-road than predicted or than observed in the inuse- vehicle dynamometer tests which serve as the model inputs. Support for these suggestions and conclusions is found in comparison of urban-air and emission-inventory HC/NOX ratios. 相似文献
609.
Yanbo Pang Norman L. Eatough William K. Modey 《Journal of the Air & Waste Management Association (1995)》2013,63(5):563-572
Abstract The real-time ambient mass sampler (RAMS) is a continuous monitor based on particle concentrator, denuder, drier, and tapered element oscillating microbalance (TEOM) monitor technology. It is designed to measure PM2.5 mass, including the semi-volatile species NH4NO3 and semi-volatile organic material, but not to measure PM2.5 water content. The performance of the RAMS in an urban environment with high humidity was evaluated during the July 1999 NARSTO-Northeast Oxidant and Particles Study (NEOPS) intensive study at the Baxter water treatment plant in Philadelphia, PA. The results obtained with the RAMS were compared to mass measurements made with a TEOM monitor and to constructed mass obtained with a Particle Concentrator-Brigham Young University Organic Sampling System (PC-BOSS) sampler designed to determine the chemical composition of fine particles, including the semi-volatile species. An average of 28% of the fine particulate material present during the study was semi-volatile organic material lost from a filter during particle collection, and 1% was NH4NO3 that was also lost from the particles during sampling. The remaining mass was dominantly nonvolatile (NH4)2SO4 (31%) and organic material (37%), with minor amounts of soot, crustal material, and nonvolatile NH4NO3. Comparison of the RAMS and PC-BOSS results indicated that the RAMS correctly monitored for fine particulate mass, including the semi-volatile material. In contrast, the heated filter of the TEOM monitor did not measure the semi-volatile material. The comparison of the RAMS and PC-BOSS data had a precision of ±4.1 μg/m3 (±9.6%). The precision of the RAMS data was limited by the uncertainty in the blank correction for the reversible adsorption of water by the charcoal-impregnated cellulose sorbent filter of the RAMS monitor. The precision of the measurement of fine par-ticulate components by the PC-BOSS was ±6-8%. 相似文献
610.
Angela E. Summers William Hearn 《Journal of Loss Prevention in the Process Industries》2010,23(6):781-783
Overfills have resulted in significant process safety incidents. Longford (Australia, 1998), Texas City (United States, 2005), and Buncefield (United Kingdom, 2005) can be traced to loss of level control leading to high level and ultimately to loss of containment. A tower at Longford and a fractionating column at Texas City were overfilled, allowing liquid to pass to downstream equipment that was not designed to receive it. The Buncefield incident occurred when a terminal tank was overfilled releasing hydrocarbons through its conservation vents.The causes of overfill are easy to identify; however, the risk analysis is complicated by the combination of manual and automated actions often necessary to control level and to respond to abnormal level events. This paper provides a brief summary of the Longford, Texas City, and Buncefield incidents from an overfill perspective and highlights 5 common factors that contributed to making these incidents possible. Fortunately, while overfill can be a complex problem, the risk reduction strategy is surprisingly simple. 相似文献