COMPUTER SCIENCE SEMINAR -Thursday, March 21, 1996 Gail Murphy, Dept. Comp. Sci. & Eng., Univ. of Washington, will speak on ``Lightweight Structural Summarization as an Aid to Software Evolution''. TIME: 4:00-5:00 p.m. ROOM: DC 1302 ABSTRACT All too often, changes to software systems lead to budget and schedule overruns. This occurs in part because software engineers lack up-to-date information about the structure of the systems they are changing. This talk describes a new approach to quickly and easily providing engineers with the desired structural information. In this approach, structural information extracted from a system's artifacts is summarized in the context of a high-level model chosen by the engineer as suitable for reasoning about the planned modification. I will discuss two new techniques developed as part of this approach. The software -------- reflexion model technique permits an engineer to use a --------- ----- high-level model as a lens through which to view the structure of the system's source code. The lexical ------- source model extraction technique facilitates the ------ ----- ---------- scanning and analysis of system artifacts for structural information that is difficult or impossible to extract using existing techniques. Each of these techniques is lightweight: the engineer is able to balance the cost and time of applying the technique with the completeness and accuracy of the desired summarization. In addition to describing the techniques, I will discuss the validation of the research, focusing on a case study of an experimental reengineering of Microsoft Excel. THEORY SEMINAR -Wednesday, March 20, 1996 Alex Lopez-Ortiz, graduate student, Dept. Comp. Sci., Univ. Waterloo, will speak on ``On-line Searching in Star Polygons''. TIME: 3:30-4:30 p.m. ROOM: DC 1304 ABSTRACT One of the main problems in robotics is to find a path from the current location of the robot to a given target, often in cases when the robot has only a partial knowledge of its surroundings. In this talk, we study the case of searches inside a region defined by a star polygon under the competitive ratio framework. More specifically, a search strategy is called c-competitive if the path traveled by the robot to find the target is at most c times longer than a shortest path. The ratio c is called the competitive ratio of the strategy. I will present upper and lower bounds for searches for a target in a star polygon. These results are the first constant competitive strategies for a family of polygons regardless of the location of the target and the initial position of the robot. Also, we argue that for rectilinear G-street polygons, knowledge of the location of the target does not improve the competitive ratio in the worst case. The Institute for Computer Research (ICR) Presents Microsoft Satellite TV Telecasts Winter 1996 Windows NT Advanced Technical Workshops Davis Centre Room 1304 University of Waterloo Waterloo, Ontario Interoperability: Connectivity Is A Basic Right (Tuesday, March 26, 1996, 12:00 noon to 1:00 pm., Davis Centre Room 1304) Connectivity, from any server to any client, and from any client to any server, Multi-Protocol Routers, Novell NetWare, Banyan Vines, Lan Server, SNA Hosts, DEC Minicomputers, Gateways, UNIX, OS/2, VMS, MVS, VM, TCP/IP, IPX/SPX, Netbios, T-1, X.25, Frac- tional T-1, ISDN, ATM, and Fiber!! Any or all of these could be a part of the connectivity nightmare you have to solve in your cor- poration? It is possible to meet the challenge of providing con- nectivity between all of these different platforms, protocols, and telecommunications infrastructures? In this telecast, we'll take a look at how Windows NT Server can meet the challenges of providing connectivity in a heterogeneous networking environment. Simply put, we'll show you how you can provide connectivity from any server to any client, and from any client to any server. Registration is free of charge. Mail/Fax/Phone Jean Webster Telephone: (519)888-4530 Institute for Computer Research Fax: (519)885-1208 University of Waterloo Email: jrwebste@icr.uwaterloo.ca Waterloo, ON N2L 3G1 -------------------------------------------------------------------------------- Counterintuitive techniques in parallel computation by Naomi Nishimura Abstract How can processors cooperate to solve problems? If the goal is to solve a series of unrelated problems, each processor can work on its own subset of the problems, independent of the actions of other processors. In this talk I explore more complicated scenarios: how might processors find the maximum element in a set of numbers, determine a function of values stored in a linked list, or traverse a tree? In each of these cases, I will demonstrate counterintuitive techniques for solving the problem in parallel. For example, the traversal of a linked list seems to be inherently sequential, as pointers have to be followed in order from the head of the list to the tail. Or do they? Come to the talk and find out. Monday, 25 March, 1996 15:30 Room to be announced. All are welcome. Doughnaughts and tea will be served. oo$$$$$ooo o$$$$$oo$$$$$oo o$$"" $$$" o$$"" $$$$$$ ""$$o C O M P U T E R o$$ $$" $$" o$" "$$ $$o $$ $$ $$o $$ $$o $$ S C I E N C E $$o "$$ $$ o$$ $$ $$ $$o "$o $$" o$$ o$$ o$$" C L U B "$$ooo$$$$$$ooo$$" $$$$ooo$$$ A Student Chapter of the ACM -------------------------------------------------------------------------------- Monday, March 25, 1996 ICR Evening Lecture Series ``Computer Simulation of the Migration of Toxic Chemicals in Groundwater'' Edward Sudicky, Waterloo Centre for Groundwater Research, Earth Sciences, University of Waterloo 8:00 p.m.; DC1302 Thursday, March 28, 1996 Computer Science Seminar ``Implementing Global Memory Management in a Workstation Cluster'' Michael J. Feeley, Computer Science & Engineering, Univ. of Washington 4:00 - 5:00 p.m.; DC1302
How CGL has worked together to clean the kitchen.