Data Analysis and Modeling to Optimize Thermal Treatment Cost and Performance          下载免费PDF全文

Jack C. Parker  Ungtae Kim  Alyson Fortune  Steffen Griepke  James P. Galligan  Amber Bonarrigo 《Ground Water Monitoring & Remediation》2017,37(1):51-66

The objective of in situ thermal treatment is typically to reduce the contaminant mass or average soil concentration below a specified value. Evaluation of whether the objective has been met is usually made by averaging soil concentrations from a limited number of soil samples. Results from several field sites indicate large performance uncertainty using this approach, even when the number of samples is large. We propose a method to estimate average soil concentration by fitting a log normal probability model to thermal mass recovery data. A statistical approach is presented for making termination decisions from mass recovery data, soil sample data, or both for an entire treatment volume or for subregions that explicitly considers estimation uncertainty which is coupled to a stochastic optimization algorithm to identify monitoring strategies to meet objectives with minimum expected cost. Early termination of heating in regions that reach cleanup targets sooner enables operating costs to be reduced while ensuring a high likelihood of meeting remediation objectives. Results for an example problem demonstrate that significant performance improvement and cost reductions can be achieved using this approach.  相似文献   

Tourists’ reviews of weather in five Indian Ocean islands     

Jennifer M. Fitchett  Su-Marie Fortune  Gijsbert Hoogendoorn 《Singapore journal of tropical geography》2020,41(2):171-189

Favourable climate forms a key resource in attracting tourists to tropical coastal destinations. Warm temperatures and clear skies are ideal conditions for tourists to spend long days on the beach and engage in outdoor activities. By contrast, rain, strong winds, high humidity and cloud cover serve as a deterrent. These factors influence tourists’ choice of destination, timing and duration of stay, and enjoyment of their vacation, and are therefore imperative to the economic sustainability of a destination. This study explores tourists’ self-reported sensitivity to and satisfaction of weather and climatic conditions during visits to five tropical Indian Ocean Islands through the analysis of 13 618 TripAdvisor reviews. An average of 12 per cent of reviews mentioned climatic factors, indicating a relatively high sensitivity to climate, with a highest proportion of 15.7 per cent of reviews for Maldives. Rain was mentioned most frequently (21 per cent of climate mentions), followed by sunshine and hot conditions. The majority of the reviews were authored in August and May, and more than 40 per cent were written in a neutral tone, with similar but lower proportions of overtly negative and positive reviews. Thematic analysis of reviews highlight the importance of preparedness amongst tourists, emphasizing the need for accurate information communicated.  相似文献   

Development of a biocidal treatment regime to inhibit biological growths on cultural heritage: BIODAM     

M. E. Young  H.-L. Alakomi  I. Fortune  A. A. Gorbushina  W. E. Krumbein  I. Maxwell  C. McCullagh  P. Robertson  M. Saarela  J. Valero  M. Vendrell 《Environmental Geology》2008,56(3-4):631-641

Existing chemical treatments to prevent biological damage to monuments often involve considerable amounts of potentially dangerous and even poisonous biocides. The scientific approach described in this paper aims at a drastic reduction in the concentration of biocide applications by a polyphasic approach of biocides combined with cell permeabilisers, polysaccharide and pigment inhibitors and a photodynamic treatment. A variety of potential agents were screened to determine the most effective combination. Promising compounds were tested under laboratory conditions with cultures of rock deteriorating bacteria, algae, cyanobacteria and fungi. A subsequent field trial involved two sandstone types with natural biofilms. These were treated with multiple combinations of chemicals and exposed to three different climatic conditions. Although treatments proved successful in the laboratory, field trials were inconclusive and further testing will be required to determine the most effective treatment regime. While the most effective combination of chemicals and their application methodology is still being optimised, results to date indicate that this is a promising and effective treatment for the control of a wide variety of potentially damaging organisms colonising stone substrates.  相似文献