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l   Who am I?
l   What is research?
l   My Research
l   Higher studies opportunities in Australia
l   Getting jobs in IT industry

Presented by:
  Muhammad Aamir Cheema, Lecturer IT at James
  Cook University Australia, Sydney campus
Who Am I? A Student
l   BSc. Electrical Engineering UET Lahore
l   Masters by research University of New South
    Wales (UNSW) Sydney (2005-2007)
l   Currently a PhD Student at UNSW Sydney
l   Research Area: Databases
Who Am I? A Teacher
l   Tutor @ University of New South Wales, Sydney
l   Lecturer IT @ James Cook University Sydney
l   Courses Taught:
    l   Database Systems Implementation
    l   Database Systems
    l   Operating Systems and Architectures
    l   E-Business Technologies
    l   Portable Programming
    l   C++
What is Research?
l   Formally “a form of systematic enquiry that
    contributes to knowledge.”

Is research boring and difficult???
      NOT AT ALL if you like solving puzzles

 Research ≈ Solving Puzzles
Let’s Play a Game1
Task: Find the missing number
 Given: Data set consists of numbers from 1 to 20

 Version 1:
   l Numbers are not displayed on the screen

 Version 2:
   l Find the missing number from the list below


 Version 1 is more difficult because:
   l No element can be seen twice
   l We cannot memorize all the numbers

    1- Data Streams: Algorithms and Applications, S. Muthukrishnan
Brute Force Solution for
Version 2
 l Is 1 missing?
 l Is 2 missing?
 l Is 3 missing? . . .
 l For each number i from 1 to n
   l Check whether i is missing or not

  Space Usage:        (n-1) elements è O(n)
  Running Time:       O(n2)
Sorting: A faster solution
l Sort the numbers
l Scan the list to find missing number
 Space Storage: O(n)
 Running Time: sorting time + final scan
                        nlogn +     n    è   O(nlogn)
Bucket: Even faster approach

l create an empty array of size n

l For each element i in the list
    l   Mark the element at index [ i ]
l Unmarked index is the missing number
  Space Requirement: O(n)
  Running Time:         O(n)
Solution for Version 1???
What we have done so far:
l   Developed solution for Version 2
l   Performance: Space Usage: O(n)
                     Running Time: O(n)
Version 1:
A solution is required that
    l   Accesses each element only once Running Time: O(n)
    l   Memorizes only one number       Space Usage: O(1)

    An example application: data passing through a network node
       (e.g; a router cannot store all the data passing through it
       and can see each element only once)
Given: numbers are from 1 to 10
Task: Nine numbers from the data are sent to
  user one by one, find the missing number

Sum of the numbers from 1 to 10 is 55
Given: Numbers are from 1 to n

l Find the sum of 1 to n numbersè S=n(n+1)/2
l For each number i
    l   S=S-i
l S is missing number
  Space Usage: O(1)
  Running Time: O(n)
My Research
l Nearest Neighbors Problem
Given a set of objects O, find k objects closest
  to any given query object
l Objects are represented by their location
    l   Find 5 taxis nearest to my current location
    l   Find 3 hotels closest to Islamabad Airport
A Brute Force Solution
Let q be the query object
l For each object x
    l   Find the distance of x from q
l   Report the k objects with the minimum
    distance from q
Problems with the brute force
l   Distance of all objects from the query object
    is to be calculated Running Time = O(n)

What if all the objects are moving (e.g cars on a
l To update the results, compute distance of all
  objects again
A better solution
l   Compute the distance of only the objects in
    vicinity of the query object q

    How to find the objects that lie in vicinity of q?

Use some spatial Index. i.e; grid index
l   Explore the objects around q in an iteratively increased circle
l   Use grid based index (visit the cells around q that intersect the


                                 r   q


1- Muhammad Aamir Cheema, Yidong Yuan, Xuemin Lin, "CircularTrip: An
Effective Algorithm for Continuous kNN Queries", DASFAA 2007, Thailand.
    Updating the result on movement of objects

l   Incoming objects: any non-result object p
    entering inside the circle
    l    Insert p into answer list
l   Outgoing objects: any result object leaving the
    l    delete p from answer list
l   Hanlde all the object updates as mentioned
l   Case 1: answer list contains k or more than k
    objects                                                         p
    l    Keep k closest objects and discard other
l   Case 2: answer list contains less than k objects
    l    Same as initial computation except the
         starting radius is distk
Higher Studies Opportunities
in Australia
1.   Student Visa
     1.    Apply in any institution you like
     2.    Get admission letter
     3.    Take IELTS exam (you need 6 band overall)
     4.    Show bank statement
2.        Permanent Visa
     1.    Get three year work experience in Pakistan
     2.    Take IELTS (minimum 7 band in each module)
     3.    Apply for Permanent residence (PR) visa
     4.    Go there and get education with benefits of being a citizen
           of Australia (e.g; more scholarship opportunities, HEC
           loan etc)
Higher studies opportunities in
l   Student Visa
     l   Quick (you will not need to wait to complete 3 yrs work
         experience to get PR)
     l   You become eligible for PR once you complete your
         degree (duration must be at least 2 years) in Australia
l   Permanent Visa
     l   Less expensive (once you are citizen your chances of
         getting scholarship grow enormously)
When Australia?
l   Education in Australia is not cheap but
    Australia is accomodating
l   Prefer European countries or try HEC
    scholarships if you are not interested in
    settling abroad
Getting Jobs in IT industry
l University degrees teach you little bit of
l A regular student becomes “Jack of all trades
  but master of none”
l To get good jobs, you must become “Jack of all
  trades AND master of ONE”
Moral: Be master in at least on skill. e.g; JAVA,
  C++, networking, web development etc.

Try to learn something about everything and everything about something
Contact Information
l   Google search “Muhammad Aamir Cheema”


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