Darrah Chavey

Tilings by regular polygons—II: A catalog of tilings

Abstract Several classification theorems involving highly symmetric tilings by regular polygons have been established recently. This paper surveys that work and gives drawings of these tilings—many of which were not shown in the original papers. Included are all tilings with at most three symmetry classes (orbits) of tiles, vertices or edges and those tilings which satisfy certain homogeneity criteria; i.e. tilings where locally congruent portions of the tiling are always equivalent under a global symmetry of the tiling.

Tilings by regular polygons—II

Abstract Several classification theorems involving highly symmetric tilings by regular polygons have been established recently. This paper surveys that work and gives drawings of these tilings—many of which were not shown in the original papers. Included are all tilings with at most three symmetry classes (orbits) of tiles, vertices or edges and those tilings which satisfy certain homogeneity criteria; i.e. tilings where locally congruent portions of the tiling are always equivalent under a global symmetry of the tiling.

A structured laboratory component for the introductory programming course

This paper presents the author’s experience with using a structured laboratory to accompany a CS 1 course. A weekly 3-hour supervised lab period was used to help teach such topics as debugging techniques, program testing and commenting, stubs and drivers, structure charts, abstract data types, operator precedence, parameters, round-off errors, data files, and some of the details of certain Pascal constructs. Some labs turned out very successful; a few others were not. We will describe our successes (and failures), along with ideas for future labs and some related work at other colleges. Introduction and Course

A multi-purpose computer lab for a small college

Small colleges face problems in constructing computer labs that are not shared by larger institutions. Due to moderate usage, it can be difficult to justify a large computer lab used for a restricted purpose, e.g. departmental labs. When only a few classes will use “high technology” presentations, it is difficult to justify equipping a “master classroom,” at least until sufficient interest is generated to leverage that construction. With smaller student bodies it becomes difficult to arrange non-credit “computer trainin,g” courses that reach enough students simultaneously. Our sulution is to use the same laboratory space for several uses. Our lab is designed for, and primarily intended for, introductory computer science classes. Lab sections of CS courses are taught there several afternoons each week, with extensive use of a computer projection system. Student use for these (and other) courses is heavy during evenings. The room is used by other courses for presental ions during morning and afternoon hours, e.g. for a course on “Cumputer Applications in Geology,” and for freshmen seminars. The projection equipped computer is installed on amobile cart and is taken to other classrooms for presentations. SeE-training software has been installed so students can learn to use computers, and most installed software, at their own pace.