Program for Tuesday, 12 September 2000

Our Next Meeting is scheduled for
Tuesday, 12 September 2000 at 7:30 P.M.
William R. Bitman
from Johns Hopkins University/Applied Physics Laboratory
will be speaking on
Reuse and Maintenance Cost
at Johns Hopkins University/Applied Physics Laboratory in Laurel, Maryland
for a joint meeting with the Baltimore SIGAda Chapter


To Members and Friends of DC SIGAda

Next Meeting:

Our Next Meeting is scheduled for 12 September 2000 as a Joint Meeting of the Baltimore and DC SIGAda Chapters. William R. Bitman, of JHU/APL, will be speaking on Reuse and Maintenance Cost. The presentation will start at 7:30 P.M. (Refreshments and Social at 7:00 P.M.) at the Johns Hopkins University/Applied Physics Laboratory in Laurel, Maryland

A deli tray and soft drinks will be served at 7:00 PM, the general meeting will start at 7:30 PM, followed by the program.

Abstract: Reuse and Maintenance Cost

Many software engineers claim that component design produces software with higher quality, decreased maintenance cost and increased reuse. This talk discusses a technique to isolate design as a factor of maintenance cost.

The Interfacing Techniques Comparison Graph visually compares applications in terms of attributes that relate to maintenance cost. Applications that have both lower coupling and lower complexity lie closer to the origin of the graph and exhibit lower maintenance cost than those that do not. This study supports the idea that compositional techniques are important for achieving these improved metrics.

The graph can be used in three ways. First it serves as a decision support tool for managers to determine whether expected maintenance savings compensate for the additional training, effort and time needed to support compositional development. Second, it functions as a decision support tool for designers and coders as they determine, for each module interface, whether to use coupled techniques or composition. The graph can help identify those situations in which the long term cost gain justifies the extra time needed for compositional design. Third, it can serve as a maintenance cost estimation tool. This study found a close correlation between predicted and actual maintenance effort.

Presenter: William R. Bitman

WILLIAM R. BITMAN received his B.A. in 1972, an M.S. from Boston College in 1975, and a Masters of General Management (M.G.A.) in M.I.S. from University of Maryland in 1994. He joined the Johns Hopkins Applied Physics Laboratory in 1993. Mr. Bitman has given presentations at the Washington Ada Symposium, ACM Computer Science Conference, Conference on Industrial and Applied Mathematics, and International Conference on Software Reuse. He has served as vice president of the ACM SIGAda Baltimore chapter. His email address is william.bitman@jhuapl.edu.

Please RSVP

Please RSVP to Charlene Hines at charlene.hines@jhuapl.edu by noon Monday the week of the meeting if you plan to come for the deli tray so that we can quantify our order. Late RSVPs are also welcome, and you can always attend even if you have not RSVP'd.

Directions From Washington, DC

From the Capital Beltway (I-495), Take the I-95 North exit;
10 miles to Columbia exit (MD Rte. 32 West);
2.5 miles to Washington, DC, exit (U.S. Rte. 29 S);
1.5 miles to Johns Hopkins Rd.;
Turn right at traffic light;
APL is located to the right, just past the service station;
Turn right at the sign: "Building 1 Visitor Parking";
Use Building 1 entrance near the flag-pole; The meeting is in the cafeteria.

Detailed Directions and Maps are available at: http://www.acm.org/sigada/locals/dc/Directions_JHU_APL.html

DC SIGAda Home Page and Maillist

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Please forward this message to people who might be interested in attending. We welcome all new members as our attendance and interests grow.

Many thanks to all earlier participants, contributors, speakers, advisors, and friends, who are involved in helping to produce and attend the meetings.

Jeff Castellow, Chair, DC SIGAda

If you have comments or suggestions, email the DC SIGAda Webmaster

updated 1 September 2000