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Help Me: Opportunistic Smart Rescue Application and System. Osnat (Ossi) Mokryn, Dror Karmi, Akiva Elkayam, Tomer Teller. Disaster Areas. China 2010. Haiti 2010. Japan 2011. Turkey 2011,2012. Indian Ocean 2004. Chile 2010. Disaster Areas. When disaster strikes
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Help Me: Opportunistic SmartRescue Application and System • Osnat (Ossi) Mokryn, Dror Karmi, Akiva Elkayam, Tomer Teller
Disaster Areas China 2010 Haiti 2010 Japan 2011 Turkey 2011,2012 Indian Ocean 2004 Chile 2010
Disaster Areas • When disaster strikes • Communication infrastructure is damaged • Rescue forces take time to arrive, organize • First hours are crucial • Skilled people, no communication • Everybody (almost) has a smartphone with 802.11 • How do we enable smart communication between people over the spontaneously formed ad-hoc 802.11 network of smartphones?
HelpMe In a Nutshell • A self-learning ad-hoc network of smartphones formed opportunistically • Smart communication:A request is delivered to the best matching person that is close enough • Messages are forwarded based on matching of user generated content to users’ skills • Ad-hoc routing based on our matching algorithm within the opportunistic network • Messages are routed to the best receiver • The network is unlimited in size, locality considerations
Problem Formalizing • Unlimited number of people, with different skills • Nodes number is not bounded (N) • Each node has a set of skills |k|={0,1,...K} • No global knowledge • People can ask or request anything • Unlimited number of possible classifications • Spontaneous requests, no local \ global knowledge • Power limitations at some or all of the nodes
Scenario Limitations • Let us consider a cloud-based Q&A scenario • Questions are classified using Google • “Apple” is 50% hi-tech, 50% fruit • Matching can be based on • Users’ ratings, location, etc. • Overall knowledge • Crisis situation • Classification based on local dictionary
Prerequisites • When a user registers and downloads HelpMe: • Cloud service. Please be prepared. • Specifies skills • Can be automated with corresponding agencies • Service creates • A list of categories of skills (or none) • Tailored dictionary for classification • Downloaded app is tailored to each user
Local Tailored Dictionary • Classification requires a dictionary • Smartphones are limited in resources • Memory, power consumption • Per user tailored dictionary created at registration • Either skills-based or general • Classification using local dictionary
Classification Accuracy Obtained With Tailored Partial Dictionaries Based on globally available general database with categories
Root Law & Order emergency Medical Rescue Non-specific rescue xxxx fire xxxx xxx water? Rescue Categories • Hierarchy of categories • Each category is divided to several sub-categories
When a disaster strikes.. • Activate app • Smartphone is used in a peer-to-peer mode over the spontaneous opportunistic ad-hoc network formed by the app • Requests are generated spontaneously upon need • Neighboring devices exchange skill sets and location coordinates during a short hello
Initial hello - exchange skill sets WiFi: received power (in dBm) decays ~ as a function of the log of the distance.Each 802.11b hop: indoor 50m, outdoor 80-120m
Questions Classification • Each word is classified and returns its set of values per category (if at all) • Using a Naive base classification • The union of all values per category is calculated: • Resulting classification • Only the highest category is chosen and published • The n-th top categories are chosen and published
How to Match? • Matching algorithm tries to route to best matching person to help • Compares classified query categories to neighbors skills • A nearby may seem able to help, but doesn’t.. • Create ranks per skill per person • Prefer a highly ranked neighbor
Ranks • Each node’s set of skills are assigned ranks • A rank corresponds to the user’s • Responsiveness • Quality of help • To enable ranking a feedback mechanism must be employed (i.e., ) Root 4 Rescue 4 rescue fire 4 0
Matching Algorithm • Given a peer k with m subscribed interests: • Given a request R is classified to categories as follows: • The request R is matched to peer k if: where T is a predefined threshold
Matching Based Routing • A request is classified at the sending side • Categories are matched to neighbors ranked skills • Forwarded (directly) to best matching neighbor • Re-classification at receiving node • Forwarding (directly) if a better matching exists AND {number of hops} < Threshold • ==> End receiver is the best possible match
User Controlled Load • Users can control their received load automatically • A highly skilled professional who helps can be overloaded • An availability setting determines load: • Accept all: users become forwarding hubs. • Accept by skills: normal matching • Accept by expertise only: filter out non-specific requests within expertise • Accept only emergency
Haggle: A publish-subscribe middleware for exchanging interests[Diot et al., 2006]. • MobiClique: Middleware for Mobile Social Networking Users that share interests are notified of each other • The MobiSoC Middleware for Mobile Social Computing: Challenges, Design, and Early Experiences Applications • Using Haggle to Create an Electronic Triage Tag • Socially-Aware Routing for Publish-Subscribe in Delay-Tolerant Mobile Ad Hoc Networks (predict routing according to social knowledge)
Experiments: The effects of Availability on Load • 4 devices corresponding to 2 skilled personnel and 2 victims • 4 different experiments with different availability settings
Server Post-Processing • All communication is stored locally • When the server is available, everything is upload to it • Location of all neighbors through out crisis • Missing people services • Stats
Conclusions • We presented a tailored application • Applicable also to rural areas, hiking, etc. • The solution is general for any spontaneous ad-hoc opportunistic network • Who wants to go play tennis/ swim? • Who wants to share a taxi to Larnaka? • Where can I find a good sea-food restaurant around? • Ranking makes it reliable
Our HelpMe System • Efficient the emergency service • Creates on-the-fly routes between people • Finds the most suitable person to help within a neighborhood • Post event, when communication is restored • Analyze the events • Help in locating lost people