Meeting Agenda

May 5, 1999

Location:: DC1304
Time:: 1:30 p.m.
Chair:: Marryat Ma

Member List

1. Adoption of the Agenda - additions or deletions

2. Coffee Hour

Coffee hour this week:: Maggie Dulat
Coffee hour next week:: Anyone?

3. Next meeting

Date:: Wednesday, May 12, 1999
Location:: DC1304
Time:: 1:30 p.m.
Chair:: Mike McCool
Technical presentation:: Celine Latulipe

4. Forthcoming

Chairs:

Tech Presenters:

5. Technical Presentation

Presenter:

Josée Lajoie (May 5)

Paper presentation:

Title:: Computer-Generated Pen-and-Ink Illustration
Authors:: Winkenbach and David H. Salesin, University of Washington
Originally Presented:: SIGGRAPH'94

Abstract:

My presentation will be an overview of the paper cited above. The paper explains the principles of traditional pen-and-ink illustration, and shows how most of these principles can be implemented as part of an automated rendering system.

6. General Discussion Items

PC Labmember accounts going... get any stuff you need off of the PC labmember account
Anything else?

7. Action List

Cables (Bill, Blair)
Alias/Side Effects talks (Mike)

8. Director's Meeting

9. Seminars

  Wednesday, 5 May 1999 at 3:30PM
  Computer Science - Algorithms and Complexity Group: Seminar

   Title:    "A lower bound for optimal hashing with open addressing"
   Speaker:  Daniel G. Frank, Computer Science, UW
   Location: DC1304
   Remarks:  This is an M.Math presentation
   Abstract:
     When using an open addressing hashing scheme, such as double hashing
     or random probing, it is possible to rearrange the keys in the hash
     table so as to minimize the expected search cost for a given key.
     Finding this optimal arrangement is an instance of the assignment
     problem, and is solvable in time O(n^3), where n is the size of the
     hash table.  Experimental results indicate that the search cost for a
     given key in an optimally arranged hash table is approximately 1.83. 
     We develop a lower bound of 1.741 for the average search cost for a
     given key in a hash table that uses open addressing. The previous
     lower bound, due to Gonnet, was 1.668. A related problem, where the
     costs for storing keys in locations are drawn from the uniform (0,1)
     distribution will also be discussed. This problem, loosely termed the
     job assignment problem with uniform (0,1) cost matrix, has an
     experimental value of 1.65. The similarities and differences between
     this problem and the optimal hashing problem will be explored.

  Wednesday, 5 May 1999 at 3:30PM
  Statistics & Actuarial Science: Seminar

   Title:    "Dispersion Effects in Analysis of Unreplicated Fractional
             Factorial Experiments"
   Speaker:  Dr. Denis K.J. Lin, Department of Management Science and
             Information Systems, The Pennsylvania State University
   Location: Math & Computer, Room 6091A
   Remarks:  The talk will be followed by coffee and cookies in MC 6123. ALL
             WELCOME!
   Abstract:
     Unreplicated fractional factorial designs are often used in industry
     as screening experiments to identify the most important factors from a
     long list.  When studying both location and dispersion effects in
     these designs, a "standard" procedure is to identify location effects
     using ordinary least squares analysis, fit a model, then identify
     dispersion effects by analyzing the residuals. In this talk, we will
     show that dispersion effects greatly complicate the analysis of
     unreplicated designs. 
     Specifically, we show that 1) if the model in the above procedure does
     not include all active location effects, then spurious (false)
     dispersion effects may appear,  2) a dispersion effect creates a
     correlation among specific pairs of location effect estimates, 3)  the
     sample variances of residuals at the high and low levels of a column
     are  independent under a mild assumption (an always attainable
     condition), and 4)  the common F test can be applied for dispersion
     effect testing under this condition. 
     In addition, a test is developed under general conditions that uses a
     simulated distribution.  In some specified cases, the distribution of
     the test statistic may be approximated by a beta distribution.

  Thursday, 6 May 1999 at 1:00PM
  Computer Science: Master's Essay Presentation

   Title:   "Database  Approaches  to Information  Management and Discovery
             on the World Wide Web"
   Speaker:  Allen Cai, graduate student, Dept. Computer Science, University
             of Waterloo
   Location: DC1304

   Abstract:
     As the World Wide Web continues to grow at an explosive rate,  
     effectively   managing   and  locating  desired information  on  the 
     Web  has  increasingly  become  a challenging  and  often  frustrating
      task.  In  recent years,  the  relevance of database concepts in
     managing and   querying   large  volumes  of  data  has  sparked
     tremendous    research   interests   in   solving   Web information  
     management   and  discovery  problems  by leveraging  existing
     database techniques. The objective of this essay is to survey some of
     the current research initiatives  in this area. Through which, to
     understand the  unique  challenges  posed to the database research
     community   by  the  Web,  and  the  various  technical innovations 
     required in database technology to address these  challenges.  At 
     this  presentation, some of the representative  research  approaches
     will be discussed, and  several real-world applications developed
     based on these approaches will be presented as examples.

  Thursday, 6 May 1999 at 2:30PM - ** MOVED TO NEW TIME/DATE (see below) **
  Pure Mathematics: Seminar

   Title:"The best constants in the M. Riesz and Hardy-Littlewood
          theorems on the boundedness of the Hilbert transform and analytical
          projection."
   Speaker:  Prof. Nahum Krupnik, University of Bar-Ilan
   Location: ** MOVED TO ** Thursday, 6 May 1999 at 1:30PM
   Abstract:

   For additional Information, Contact:
        Name:   Debbie Brown
        Phone:  3484

  Friday, 7 May 1999 at 9:30AM
  Computer Science: Master's Essay Presentation

   Title:    "A Study of Graph Partitioning Algorithms"
   Speaker:  Qingwei Liu, Computer Science, UW
   Location: DC1331
   Abstract:
     Abstract not yet available.

  Friday, 7 May 1999 at 3:30PM
  Combinatorics and Optimization: Colloquium

   Title:    "Tutte Colloquium - Triangulated Squares"
   Speaker:  Prof. W.T. Tutte, Dept. of Combinatorics & Optimization,
             University of Waterloo
   Location: Math & Computer, Room 5158
   Abstract:
     For a complete abstract, please visit our website.

   For additional Information, Contact:
        URL:   
              http://www.math.uwaterloo.ca/CandO_Dept/Seminars/upcoming.html