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Mobile Consumers andLocation-Aware Information Management Managing Server-Based Location Information for Client-Based Location-Aware m-Commerce Applications of Location-Variant Mobile ConsumersJim WyseWireless Communications and Mobile Computing Research Centre (WCMCRC) Seminar Series, Faculty of Engineering and Applied Science, Memorial University, March 2010
Mobile Commerce (m-Commerce) • transactions through communication channels that permit a high degree of mobility by at least one of the transactional parties.
Location-Aware m-Commerce • m-business with location-referent transactions: transactions in which the geographical proximity of the transactional parties is a material transactional consideration. • Critical capability: location awareness. • Yuan and Zhang (2003): “location awareness … is a new dimension for value creation” in a wide variety mobile business applications.
“Location-Awareness” The capability to obtain and use the geo-positions of the transactional parties to perform one or more of the CRUD (create, retrieve, update, delete) functions of data management.
The Data Management Problem • Location-referent transactions are supported by proximity queries: What is my proximity to a goods-providing (or service-offering) location in a selected category? • A proximity query bears criteria that reference static attributes (e.g., hospital) and dynamic attributes (e.g., nearest). • Proximity queries are burdensome to conventional query resolution approaches (Nievergelt and Widmayer, 1997).
Proximity Query Resolution Proximity Portals The Client-Based i-DAR Prototype (Architecture: Client-Based Functionality, Server-Based Locations Repository)
Web-Based i-Prox Prototype (Architecture: Functionality and Locations Repository are both Server-Based)
Location-Aware Linkcell Method • Transforms mu’s position (47.523° N, 119.137° W) into a linkcell (N47W119). • Initiates search sequence at mu’s linkcell {N48W119, N48W118, N47W118, • N46W118, ….} • Permits large numbers of locations to be excluded as proximity portal candidates. • Requires an appropriate linkcell ‘size’ (S) to give superior performance.
Proximity Query Resolution Time Query Resolution Time (ms) Linkcell Size (S)
Optimal Linkcell Size Solve …. PTC(S) = 1 – (1 – nTC/N)N/CS 0.6 . . . (A) . . . . for relational table names (linkcell “name increments” nTC is the number of locations in category, TC, N is total number of locations, and CS is the number of linkcells of size, S, created from the N locations.
Data Management Methods for Location-Based Services • Conventional (Enumerative) Methods • where C, U, D are ok but not R. • Linkcell-Based Methods • where R is ok but C, U, and D are burdened somewhat.
MCRs and SCRs • Multiple Category Repositories (MCRs) • Single Category Repositories (SCRs) • Equation (A) applies to MCRs but not to SCRs • For SCRs, nTC = N PTC(S) = 1, for all S.
Single Category Repositories • For SCRs, it is hypothesized that optimal values are given by: • P(S) = 1 – (1 – S2/4A)N 0.6 . . . (B) • where A is the total geographical coverage, • S is the linkcell size, and • N is the number of locations. • Some preliminary results ……
1. Location-Sensitive Mobile Services … incorporating … 2. Location-Aware Business Processes … supporting … 3. Location-Referent Transactions 1. Context-Sensitive Mobile Services … incorporating … 2. Context-Aware Business Processes … supporting … 3. Context-Referent Transactions Location-Based Context-Based
Notation Mobile User’s Situation Set of Circumstances MUS {C0, C1, . . ., CN} Let C0 represent a mobile user’s spatial circumstance, then MUS {C0, C1, . . ., CN} requires a Context-Aware m-Business Service (also Location-Aware Proximity Portal Problem) MUS {C1, . . ., CN} requires a Context-Aware m-Business Service (not Location-Aware)
MUS {C0, C1} Context-Aware (Location-Aware) Special Case (the “Locationalized Business Directory” Case) Generalize to {C0, C1, C2, …. CN}
Prototypical Context-Aware System Context Server “contextualizes” Proto-Contexts
Proto-Context Types 1. Non-Locationalized Proto-Contexts 2. Locationalized, Categorized Proto-Contexts (e.g., Locationalized “Classified” Business Directories) 3. Locationalized, Uncategorized Proto-Contexts (e.g., Specialized, Locationalized Business Directories a. k. a., Single Category Repositories)
Linkcell Method (SCR) Reformulation Linkcell Construct. . . from: . . . to: • Linkcell Optimization. . . from: . . . to: P(S) = 1– (1 – nTC/N)N/CSP(S) = 1– (1 – S2/4A)N
Proto-Context Data Management Methods 1. Non-Locationalized Proto-Contexts use conventional CRUD methods 2. Locationalized, Categorized Proto-Contexts use ‘standard’ Linkcell-Based CRUD methods 3. Locationalized, Uncategorized Proto-Contexts use reformulated Linkcell-Based CRUD methods
Recent Research Outputs Book Chapters – Professional/Academic Press Mobile Computing: Concepts, Methods, Tools, and Applications (2009) Advanced Principles for Improving Database Design, Systems Modeling, and Software Development (2008) Handbook of Research on Innovations in Database Technologies and Applications: Current and Future Trends (2009) Journal Article International Journal of Wireless and Mobile Computing (2009) Patent CIPO Patent 2508977 (2010)
Contextualization Example MUS: Recreational Boater Proto-Context 1: Small Craft Harbours(Marine Services) Proto-Context 2: Smart Bay(Real-time Weather Conditions, etc.) Proto-Context 3: Public Libraries(Free Wireless Internet) Proto-Context 4: Lighthouses(Navigational Markers) Proto-Context 5: Municipalities(Information, Services) Generated Context: MobileMariner
Mobile Consumers andLocation-Aware ( Context-Aware) Information Management Jim Wysewww.busi.mun.ca/jwyseThank you!! Wireless Communications and Mobile Computing Research Centre (WCMCRC) Seminar Series, Faculty of Engineering and Applied Science, Memorial University, March 2010