Category Archives: news

Poster presentation: Ram Dahal

Saturday May 16 2013:
Ram Dahal presented a poster about his research at the Meeting of the Minds conference at the University of Lethbridge. The conference is organized by the graduate students’ association and is the main event where students showcase their work to the community, establish new contacts, exchange ideas, and have a good time.

Optimization Seminar – Feb 28

Thursday Feb 28 from 12:15-13:05
Room E-575

Speaker: Ram Dahal
Ram will talk about a paper on joint routing and scheduling in wireless networks by Mahmoud and Elmallah, “An algorithm for incremental joint routing and scheduling in wireless mesh networks”, WCNC 2010.
Everyone is welcome. All graduate students are encouraged to attend. Light refreshments will be served.

Optimization Seminar – Feb 14, 2013

Thursday Feb 14 from 12:15-13:05
Room E-575

Speaker: Mark Thom
Mark will talk about another dynamic programming algorithm used to solve several facility location problems on the real line. The results appear in a 1996 paper of Tamir and Megiddo.
Everyone is welcome. All graduate students are encouraged to attend. Light refreshments will be served.

Optimization Seminar – Feb 7, 2013

DATE CHANGE: Thursday Feb 7 from 12:15-13:05
Speaker: Mark Thom
Theme: Mark will talk about covering facility location problems on the real line. He will talk about his result on the customer constrained maximum covering, then about a paper by Tamir & Megiddo on facility constrained covering on the real line.

Room: E575
Thursdays, 12:15 – 13:05
Everyone is welcome. Graduate students are encouraged to participate. Light refreshments will be served.

Optimization Seminar – Jan 29, 2013

Title: “Algorithmic aspects of capacity in wireless networks”, Kumar
Speaker: Ram Dahal
Theme: we continue the topic of routing and interference as generalizations of max flow problems begun last week. The paper precedes Alicherry presented last week and the paper is simpler as channel assignment is not considered.

Room: E575
12:15 – 13:05
(everyone is welcome – grad students are encouraged to participate)

Optimization Seminar – Jan 22, 2013

Our Optimization Research Group Seminar starts this semester on Tuesday Jan 23 at noon with Ram Dahal’s presentation of Alicherry et al. “Joint Channel Assignment and Routing for Throughput Optimization in Multiradio Wireless Mesh Networks”. The theme of the paper is a generalization of the Maximum Flow Problem to account for interference and channel assignment in wireless networks. Everyone is welcome. Graduate students are encouraged to attend.

Location: Optimization Lab, C553
Time: 12:10 – 13:00

Optimization Research Group – Distinguished seminar series 2013/14

I am pleased to announce that our Optimization Research Group Seminar has just received funding from PIMS. This will allow us to bring distinguished external speakers, as soon as the summer of 2013.

Stephen Nsoh – MSc thesis defense (17-sep-12)


SEPTEMBER 17, 2012
11:00 – 13:00
Room: D631


Date: SEPTEMBER 17, 2012
Time: 11:30 A.M. – 1:00 P.M.
Place: D631
(20 min. public presentation followed by examination)


The IEEE 802.16 standard popularly known as WiMAX is at the forefront of the technological
drive. Achieving high system throughput in these networks is challenging due to
interference which limits concurrent transmissions. In this thesis, we study routing and link
scheduling inWiMAX mesh networks. We present simple joint routing and link scheduling
algorithms that have outperformed most of the existing proposals in our experiments. Our
session based routing and links scheduling produced results approximately 90% of a trivial
lower bound.
We also study the problem of quality of service (QoS) provisioning in WiMAX mesh
networks. QoS has become an attractive area of study driven by the increasing demand
for multimedia content delivered wirelessly. To accommodate the different applications,
the IEEE 802.16 standard defines four classes of service. In this dissertation, we propose a
comprehensive scheme consisting of routing, link scheduling, call admission control (CAC)
and channel assignment that considers all classes of service. Much of the work in the
literature consider each of these problems in isolation. Our routing schemes use a metric
that combines interference and traffic load to compute routes for requests while our link
scheduling ensures that the QoS requirements of admitted requests are strictly met. Results
from our simulation indicate that our routing and link scheduling schemes significantly
improve network performance when the network is congested.

Examination Committee:
Dr. Robert Benkoczi Supervisor
Dr. John Zhang Supervisory Committee Member
Dr. Saurya Das Supervisory Committee Member
Dr. Howard Cheng Examination Committee Chair