Continuous Detour Queries in Spatial Networks

Continuous Detour Queries in Spatial Networks

ABSTRACT:

We study the problem of finding the shortest route between two locations that includes a stopover of a given type. An example scenario of this problem is given as follows: “On the way to Bob’s place, Alice searches for a nearby take-away Italian restaurant to buy a pizza.” Assuming that Alice is interested in minimizing the total trip distance, this scenario can be modeled as a query where the current Alice’s location (start) and Bob’s place (destination) function as query points. Based on these two query points, we find the minimum detour object (MDO), i.e., a stopover that minimizes the sum of the distances: 1) from the start to the stopover, and 2) from the stopover to the destination. In a realistic location-based application environment, a user can be indecisive about committing to a particular detour option. The user may wish to browse multiple (k) MDOs before making a decision. Furthermore, when a user moves, the kMDO results at one location may become obsolete. We propose a method for continuous detour query (CDQ) processing based on incremental construction of a shortest path tree. We conducted experimental studies to compare the performance of our proposed method against two methods derived from existing k-nearest neighbor querying techniques using real road-network data sets. Experimental results show that our proposed method significantly outperforms the two competitive techniques.

EXISTING SYSTEM:  

Existing method a current location-based services where users have to report their exact locations to the database server in order to obtain their desired services. For example, a mobile user asking about her nearest restaurant has to report her exact location. With untrusted service providers, reporting private location information may lead to several privacy threats. LS make spatial data available to the users through one or more location servers (LS) that index and answer user queries on them. Examples of spatial queries could be “Where is the closest hospital to my current location?” or “Which pharmacies are open within a 1 km radius?” In order for the LS to be able to answer such questions, it needs to know the position of the querying user.            Existing an peer-to-peer (P2P) spatial cloaking algorithm in which mobile and stationary users can entertain location-based services without revealing their exact location information. The main idea is that before requesting any location-based service, the mobile user will form a group from her peers via single-hop communication and/or multi-hop routing. Then the spatial cloaked area is computed as the region that covers the entire group of peers. 

PROPOSED SYSTEM: 

In this paper, we propose the network-based anonymization and processing (NAP) framework, the first system for K- anonymous query processing in road networks. NAP relies on a global user ordering and bucketization that satisfies reciprocity and guarantees K-anonymity. We identify the ordering characteristics that affect subsequent processing, and qualitatively compare alternatives. Then, we propose query evaluation techniques that exploit these characteristics. In addition to user privacy, NAP achieves low computational and communication costs, and quick responses overall. It is readily deployable, requiring only basic network operations. We propose a framework for anonymous query processing in road networks. We design location obfuscation techniques that (i) provide anonymous LBS access to the users, and (ii) allow efficient query processing at the LBS side. Our techniques exploit existing network database infrastructure, requiring no specialized storage schemes or functionalities. We experimentally compare alternative designs in real road networks and demonstrate the effectiveness of our techniques.

HARDWARE & SOFTWARE REQUIREMENTS:

HARDWARE REQUIREMENTS: 

·                     System                 :         Pentium IV 2.4 GHz.

·                     Hard Disk            :         40 GB.

·                     Floppy Drive       :         1.44 Mb.

·                     Monitor                :         15 VGA Colour.

·                     Mouse                  :         Logitech.

·                     Ram                     :         512 MB.

  

SOFTWARE REQUIREMENTS: 

·                     Operating system           :         Windows XP Professional.

·                     Coding Language  :         ASP .Net, C#.NET

·                     Tool                     :         Visual Studio 2008.

·                     Database              :         SQL SERVER 2005

REFERENCE:

Sarana Nutanong, Egemen Tanin, Jie Shao, Rui Zhang, and Kotagiri Ramamohanarao, “Continuous Detour Queries in Spatial Networks”, IEEE TRANSACTIONS ON KNOWLEDGE AND DATA ENGINEERING, VOL. 24, NO. 7, JULY 2012.