The conceptual stage of building design is where the most important decisions are made, for example, in determining the choice of structural elements such as floors. However, decisions made at this ...stage, particularly those involving costs and speeds, are often based on subjective judgement, rules of thumb and familiarity. This paper reports on the development of a computer spreadsheet tool that employs a more objective and systematic procedure in selecting concrete floors at the conceptual design stage, in which costs and speeds are quantitatively evaluated using, respectively, the method of elemental estimating and a simple bar chart technique, but in conjunction with a specially developed "lead-in index"method. The results of the evaluation are then tabulated and systematically ranked to facilitate selection of the best floor system. The tool would thus assist engineers to make a more well-informed and rapid choice of floor systems at the early design stage.
Mass balances are an effective method for evaluating the reliability of experimental test data obtained from coal preparation plants. Although conceptually very simple, the mathematics associated ...with this procedure can be overwhelming when conflicting data sets or complex circuits are evaluated. Fortunately, modern spreadsheet programs now include powerful minimization routines that can be readily adapted to solve common mass balance problems. This article reviews the mass balance problem and describes how embedded spreadsheet tools can be used to reconcile conflicting data. An example problem involving the evaluation of data from a spiral-flotation circuit is presented to illustrate the inherent simplicity of this new approach to solving mass balance problems.
Needs for extending the principles of a sustainable urban drainage approach to the winter season with snow and pollutant accumulations have been so far unanswered. One of the first steps to remedy ...this situation is to make available a prototype snow management tool (PSMT) described herein. It is a simple empirical spreadsheet tool, as yet untested, which uses generally available input data to simulate accumulation of snow (as snow water equivalent) and pollutants in an urban catchment, intermittent snowmelt episodes, and snow management options including in situ melting, removal from the catchment, treatment of snowmelt by settling, and snow disposal in the receiving waters. The tool output comprises snow and the selected pollutant mass balances, and pollutant concentrations in snowmelt from individual snow deposits. Such data provide decision support for choosing the methods of disposal for individual snow deposits. The testing and refinement of the tool is planned.
•The simulation tool CoHort supports strategical thinking in fruit tree farms.•CoHort was designed with the participation of apple farmers and technicians.•CoHort estimates impacts of management ...change on farm performances and work balance.•CoHort is flexible and adapted to a diversity of farm structures and projects.
Strategic decisions condition the orientation and associated agricultural practices of farms for many years, especially in fruit production where trees are planted for ten to fifteen years. However, this type of decision is rarely addressed in decision support approaches. An approach was developed to support strategic thinking in fruit tree farms through the use of a simulation tool called CoHort and built in Excel®. CoHort evaluates the impacts of a given set of practices on the economic performances (gross and net margins), labour organization and phytosanitary performances (Treatment Frequency Index) of fruit tree farms. It has been built with cooperatives technicians and used with apple farmers in a participatory process to integrate the needs and objectives of the farmers and technicians. The approach alternates between simulations with the tool and discussions with the farmer. It is illustrated for two apple farmers in France aiming to reduce their pesticide use. The first farmer wanted to convert five hectares out of eight to organic production. Simulations showed that the raw margin was increased by 259%, the Treatment Frequency Index was reduced of 26%, but the labour demand was 9% higher. The second farmer wanted to replace 1.5 hectares out of 15ha with a new scab-resistant cultivar. Results showed that the average TFI at the farm scale was decreased by 17%, the labour demand was similar, and the raw margin increased by 5%. Based on simulation outputs apple farmers could estimate the possible impacts of their projects to their farm. The tool flexibility allows using it with different farm structures and projects.
With more than one billion people lacking access to electricity in the world, ensuring universal access to electricity by 2030 remains a major challenge which cannot be left to the government ...initiatives alone. Access to local information and identification of potential areas for investment can be a challenge for investors. This paper provides a tool for preliminary assessment of potential markets for off-grid electrification in developing countries and applies this to Ghana to demonstrate its applicability. A multi-criteria approach is used to rank the districts according to the overall potential and the best markets and least favourable areas for investment are identified. The tool offers flexibility to include new inputs to the analysis and the factor weights can be adjusted as appropriate. The case study shows that the tool can effectively identify potential areas from a list of candidates and offers support to analysts.
Drug cost is considered an important factor in treatment compliance for cancer patients. However, it is difficult to calculate individual drug costs. We were previously unable to provide sufficient ...information on costs to cancer patients starting drug therapy. Therefore, we developed a tool, in the form of a spreadsheet, which calculates drug costs for breast cancer treatment. This software tool runs on every terminal for electronic medical charts in our hospital. To evaluate the tool, we created 10 fictional breast cancer patient sets. Five pharmacists calculated the drug costs for a single regimen using method A (without software) and method B (with software). The pharmacists then calculated the drug costs for 3 regimens in the same way. We compared the time taken to calculate costs using method A and method B. For the single regimen, the mean time for method B (22.6±6.9 s) was 6.4-times shorter than that for method A (145.2±28.3 s, p<0.0001). For the 3 regimens, the mean time for method B (35.5±5.0 s) was 8.9-times shorter than that for method A (315.8±43.1 s, p<0.0001). The differences observed were statistically significant. By using the software, we were able to shorten the calculation time for drug costs, and therefore, alleviate the burden on medical staff.
Price of coal is central to cost competitiveness of any thermal power plant as well as coal processing plant. The consumers of power-plant-grade coal are primarily interested in the cost of clean ...coal at a suitable level of quality for their process, but in many cases, this quality is not economically justified for coal preparation plants. Therefore, a proper allocation of credit or penalty for both ends is a matter of considerable importance that must be resolved. In this article, a technique is presented to arrive at a trade-off for such conflicting situations. The technique is about a numerical solution to the constrained nonlinear cost optimization problem involving a multivariable objective function. The merit of this approach is illustrated by means of a case study with six different coals of different characteristics.
The desired coal quality is not same for all the consumers. This quality may be limited to the maximum ash content, Useful Heat Value (UHV), size, or it may be its price. In some cases it is ...difficult to predict the economic feasibility and to maintain the optimum operating parameters for the washing equipments to achieve this quality. In this article, a methodology is presented to quantify the economic feasibility and to determine the optimum operating parameters accordingly. But in actual practice, these operating parameters vary within certain ranges and affect the product quality. This uncertainty in product quality has been quantified by using a Monte-Carlo-based simulation method. To illustrate, six coals of different characteristics are considered. The result leads to a conclusion that optimum operating conditions for different quality are quite different. This method can be used to determine the optimum operating parameters and to predict the economic feasibility in different situations.
The environmental risk assessment of substances is introduced and the various controls used to protect the environment are outlined. The European notification system and the risk assessments required ...as part of the system are detailed. Through an examination of the existing European Union System for the Evaluation of Substances tool and sensitivity analyses based on variability in the measurement of physico-chemical properties for a substance, a spreadsheet model was developed to allow multiple risk assessments for the same substance to be calculated simultaneously. The development and testing of the NECXES spreadsheet tool are documented in detail. Data for the capacity and dilution factor at Sewage Treatment Plants (STPs) in England and Wales were collated and statistically analysed and compared to European default values used for generic risk assessments. The default capacity value for STPs (10,000 population equivalents) was protective of 70% of the STPs sampled. The remaining 30% however, a small number of large works, contributed 94% of the total effluent discharged from STPs in England and Wales. The STP data were used with the NEXCES tool to perform and compare probabilistic risk assessments to those calculated using deterministic methods for a number of test substances. The probabilistic calculations produced a lower median exposure concentration for water than the generic assessment for all of the test substances. Regression analysis allowed the probability of adverse effects to be quantified for the various deterministic risk values. The NEXCES tool was also used to develop a rapid assessment tool for new substances in the form of contour plots, which can be used to assess the risk of substances using minimal data. The main conclusions and contributions to the academic and industrial fields, as well as the field of environmental technology are presented. Areas where there are opportunities for further research are also outlined.
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