Ambulance Dispatch System

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Ambulance Dispatch System

• Design Specification

Ryan KellyScott MooreJonathan Sanborn
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Overview

• Dataflow Diagram
• Architecture Diagrams
• Component Diagrams

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Dataflow Diagram
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Dataflow Diagram
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Component Architecture Diagram
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Network Architecture

• Abstraction layer between client and server
• Server methods made available via proxy client
• ClassClient encodes message, passes over TCP/IP
  to ClassHandler for decoding

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Components

• City Simulation
• Map Controller
• Allocator
• Exception Monitoring
• Logging
• Operator Terminal
• Supervisor Terminal

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City Simulation

• Model component of the system
• Central repository for ambulances and incidents
• Maintains map of the city
• Ambulances and incidents separate from map

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City Simulation Ambulance

• Ambulances are identified by a unique ID
• Store incident assignment (an incident ID)
• Store availability as a boolean
• Current location stored as an Address

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City Simulation Incident

• Incidents are identified by a unique ID
• Creation time stored as a Date object
• If an incident is not responded to in time, the
  time of this exception is stored
• Location stored as an Address
• Other information stored in IncidentDescriptor

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City Simulation Address

• The information necessary to locate an object
• Not explicitly linked to the map
• Simplifies data structures
• Reduces storage requirements
• Three parts
• Street name
• Street number
• Suite number

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City Simulation Map

• Abstract representation of a city
• Two fundamental units
• Streets
• Intersections
• Represent city as a graph
• Streets become edges
• Intersections become vertices

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City Simulation Map

• Edges are related to addresses
• Street name
• Address range
• Vertices relate streets to each other
• Edge can return closest vertex to a given address
• Assumes linear distribution of street addresses

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Map Controller

• Interface module for the City Simulation
• Allows ambulances and incidents to be created,
  modified and deleted
• getDistance(Address a1, Address a2)
• Makes allocation possible
• Dijkstras Shortest Path Algorithm

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Map Controller getDistance(Address a1, Address
a2)

• Step 1 Find closest vertex to each address
• Ask each edge if the address is contained
• Edge returns closest vertex
• Step 2 Use Dijkstras Shortest Path algorithm
• Finds shortest route between vertexes
• Edges must be assigned path cost
• Returns the distance between two locations
  accurate to the nearest vertex (one block)

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Allocator

• Scans for nearest ambulances to an incident
• Reports possible duplicate incidents
• Assigns ambulances to incidents

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Exception Monitoring

• Centralizes passing of exception messages
• Scans for incomplete incidences

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Logging

• Receives and logs messages from other components
• Tracks statistics
• Number of calls
• Average response time
• Average completion time
• Number of exceptions

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Operator Terminal

• Design goals (nonfunctional requirements)
• Simplicity
• Efficiency
• Must fulfill the functional requirements
• Create and update incidents
• Dispatch ambulances
• Update ambulance location

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Operator Terminal
Dispatches
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Operator Terminal
Position Updates
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Operator Terminal
Incident Updates
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Operator Terminal
New Incidents
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Supervisor Terminal

• Design goals (nonfunctional requirements)
• Simplicity
• Efficiency
• Greater degree of control
• Must fulfill the functional requirements
• Allow correction of errors, manual allocations
• Show statistics
• Update fleet and map information

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Supervisor Terminal
Manual Allocations
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Supervisor Terminal
When Problems Arise
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Supervisor Terminal
Statistics
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Supervisor Terminal
Fleet and Map Info