The software distributed is a standard Microsoft (Ms) Excel Add-in. It consists of one Add-in file (named radiocalc.xla), one compiled html help file (named radiocalc.chm) and one rainfall data file if the approximate local reference inventory has to be estimated. The minimum software environment is a copy of Excel 97 operating on Windows 98 and Internet Explorer 5.0. It was developed on a PC running Windows 98 and Excel 2000. User's feedbacks on its performance on other system combinations would be most welcome.
6.1.1. Add-in installation
To install the programme, one only has to move the files to a user-preferred folder. It is highly recommended that all three files should be saved in one folder. The ideal location is the 'Add-in' folder created by the Windows setup programme.
One way to find the location of this folder on your PC is to try saving a workbook as an Add-in and note down the full path to the prompted default folder provided by Excel.
When you use the Add-in for the first time, the following steps must be followed to prepare it for use:
(1) Start Excel
(2) Navigate the menu system as follow: Tools | Add-in. If the files have been saved in the recommended folder, the Add-in named 'radiocalc.xla' should be in the list of Add-in available. Otherwise, click the 'Browse' button, find the file 'radiocalc.xla' and open it.
It should, then, appear on the list. Make sure the leading box in front of the 'radiocalc.xla' is checked by clicking it if necessary.
(3) Close the Add-in window and a new menu item named 'radionuclide inventories conversion' should be added to the 'Tools' menu. Then, you can use the Add-in by simply clicking this newly added menu item.
(4) If you have to save help files separately from the Add-in file itself, you need to specify the correct path via the 'options' button on the main menu before the online help for the Add-in can function properly.
(5) Apart from ‘Add-ing’ one entry to the windows registry, no other files or modifications to the user's system files and configuration are required.
6.1.2. Removing the Add-in
Removal of the Add-in from your computer involves two steps:
(1) Remove the added menu item from the menu system: navigate the Add-in list via: Tools
|Add-in. Then, remove the Add-in by clicking on the leading box. The programme will also delete its entry to the windows's registry.
(2) Remove the files themselves: go to the folder and delete the files as usual.
Caution: deleting the files before removing the added menu item is not good practice and should be avoided.
6.2. Using the Add-in
6.2.1. Input data management
The data for the sampling points should be entered into an Excel worksheet and listed in columns which run from the top to the bottom of the slope. The same numbers of entries will be expected for the values relating to sample inventory, particle size correction factor, etc.
With the current version of the programme, an active worksheet is required for it to run. All input data are expected to be in this worksheet and the output results will also be saved in it.
6.2.2. Interaction with the interface
The interface of the Add-in should be familiar to any Microsoft Windows user. Designed as a tool for research purpose, it is assumed that the user knows how to deal with command buttons, option buttons, input boxes, etc., in a Windows operating system.
With this Add-in, users also have to select a particular set of values or range (multiple cells in a single column) for data input and output. This can be done by selecting the first cell in the range, holding down the mouse, dragging it over the cells, and releasing the mouse when you reach the last cell. If a mistake is made, one can simply click the first cell and start all over again. Where a range is expected, the text input box is locked (no keyboard entry will be allowed) to avoid error in its specification. Instead, an arrow-labelled button is provided to its right. The user simply clicks the button to select a range interactively from the active worksheet.
6.3. Provision of help
The Add-in has online help included. It is a compiled html help file that can be viewed while the programme is running or independently as an ordinary file as long as you have Microsoft Internet Explorer (version 5 and above) installed.
7. CONCLUSIONS
Conversion models are a key requirement in the use of fallout radionuclides to obtain information on soil redistribution rates, since they are able to convert measurements of the reduction or increase in the radionuclide inventory of a sampling point, relative to the local reference inventory, into a quantitative estimate of the erosion or deposition rate involved.
A wide range of conversion models are available for use with 137Cs measurements and a limited number of models are now being developed for use with 210Pbex and 7Be.
In order to obtain a degree of consistency and standardisation in the use of such conversion models across a group of researchers involved in an ongoing IAEA Coordinated Research Project, a group of nine models covering applications involving both cultivated and uncultivated areas and the three fallout radionuclides, has been developed and documented.
Furthermore in order to facilitate the application of the models in a standardised manner and to promote their use by the wider scientific community, a user-friendly software package, based on an Excel Add-in has been produced and made available to interested persons. It is hoped that the use of a standardised set of conversion models by the CRP participants and other researchers will facilitate exchange and comparison of results and that the wider testing of the conversion models will generate an improved understanding of their advantages and limitations and thus assist the further development and improvement of such models.
ACKNOWLEDGEMENTS
The work on assembling, developing and documenting the set of nine conversion models described in this contribution and the production of the user-friendly software to assist in applying the models were undertaken to support implementation of the IAEA Coordinated Research Project on ‘Assessing the effectiveness of soil conservation techniques for sustainable watershed management using fallout radionuclides’ (D1-50-08), through technical contract UK-12094.
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SEDIMENT BUDGETS AND SOURCE DETERMINATIONS USING