Item: A database design for storage and retrieval of snow profiles on a pc
Title: A database design for storage and retrieval of snow profiles on a pc
Proceedings: Proceedings of the 1994 International Snow Science Workshop, Snowbird, Utah, USA
Authors: Peter Weir. P. Geo., Research Officer, Snow Avalanche Programs, British Columbia Ministry of Transportation and Highways, 940 Blanshard St., Victoria, BC, Canada V8W 3E6, Tel. (604) 387-7517, Fax (604) 356-814, E-mail: PWeir@Galaxy.gov.bc.ca 3
Abstract: An application for plotting snow profiles has been designed for the Windows Personal Computer operating environment. A Graphical User Interface allows the IASH / ICSI symbols to be presented in pick lists with accompanying textual descriptions. A mouse or similar pointing device is used to make selections wherever possible. Provided that density measurements are made, the application automatically computes the equivalent water content of each layer and of the entire snowpack. A weighted average snowpack density is also computed. The application uses the graphical area on the left of the profile, traditionally reserved for plotting Ramsonde hardness, to display a plot of the results of a hand hardness analysis and / or a cumulative plot of slope parallel shear stress (a function of slope angle, layer thickness and density). The application supports a display-only mode, a fixed corporate format and a mode that supports Dynamic Data Exchange. In its simplest form the application stores data from a single snow profile iIi acomma delimited ASCn file. This approach suits small sites and facilitates the transfer and digital exchange of snow profile information. A database has been designed to accompany the application so that a variety of other PC based tools, including a Rule Based Expert System used for snow profile interpretation, can share its data. A logical data model is presented for use in the design of a relational database. Entity relationship diagrams are explained. In a larger corporate application, as exists in the BC Ministry of Transportation and Highways, a database approach is warranted to facilitate the storage and retrieval of the large number of snow profiles collected each season. Queries can be run to identify and display snow proftles from a given date range, area or region, and / or proftles which satisfy any given set of snowpack conditions.
Keywords: density, snowpack conditions, pc
Digital Abstract Not Available