by Rolf Oswald
Spatial data, such as that gathered from satellite images, presents real dilemmas when shared information over heterogeneous networks and geographical-information systems. In particular, the challenge of dissimilar file formats must be overcome. Rolf examines how Manitoba's Information Utility tackles this and other thorny data-exchange problems.
by Pierre J. Dion
Data compression is one means of achieving efficient data transfer. However, efficiency across disparate computer systems can be limited by the lack of cross-platform tools. Pierre presents an implementation of LZH compression for MS-DOS, UNIX, and MVS.
by Edward Dowgiallo
In the database world, interoperability refers to the ability to build applications that can simultaneously access data in different databases provided by different vendors; transportability is the ability to move an application from one network/hardware combination to another while using the same database. Ed examines the strategies database vendors implement to make this possible.
by Eric Giguere
The REXX language interface provides a simple way to customize the OS/2 Workplace Shell environment. Eric also takes a peek at the upcoming object-oriented REXX being developed by IBM.
by Bruce Schneier
The International Data Encryption Algorithm (IDEA) may be one of most secure block algorithm available to the public today. Bruce examines its 128-bit long key (over twice the length of the familiar DES) and unravels the algorithm for both encryption and decryption.
by James F. Farley and Peter D. Varhol
Our authors use Vision, a graphical front end for data display, and Visual Basic to build an application that acquires and displays sensor data from an optical fire detector.
by William Stallings
The OSI network-management system, which relies on an object-oriented design, provides an operator interface for monitoring and controlling network activity.
by Ramin Firoozyi
StarView is a cross-platform C++ application framework that operates across Windows, Macintosh, NT, OS/2, OpenLook, and Motif. C++ code written to this application framework can be copied from one machine to another and rebuilt, resulting in a native executable that has the speed of a C++ application and the look-and-feel of the native GUI.
by Darrell Diem
Wireless networks, which can be implemented as LANs, MANs, or WANs, have their own unique technical challenges. Darrell examines how minimum airtime algorithms can reduce transmission errors and wireless-network airtime costs.
by Michael Swaine
Michael examines powerful tools for manipulating HyperCard extensions.
by Al Stevens
Al continues with D-Flat++, this month implementing classes for tool bars and tool buttons using a text-editor named TED to illustrate how you can use these classes. TED sports a menu bar, status bar, and tool bar, and it lets you work on one text file at a time.
by Tom Swan
Tom uses frequency distribution to explore if pseudorandom numbers really are. In particular, he examines a statistical method known as the "chi-square distribution."
by Andrew Schulman
Andrew presents VXDLIST, a program that walks the Windows Enhanced mode VxD chain and displays the names of all VxDs loaded on the system. VXDLIST will be particularly useful for exploring the upcoming "Chicago" operating environment, which is based on VxDs.
by Jonathan Erickson
Mobile Robots is about more than just silicon-based creatures scurrying around underfoot. It's really an application of an exciting approach to organizing intelligence systems using an architecture referred to as "subsumption."
by Jonathan Erickson
by you
by Michael Swaine
Copyright © 1993, Dr. Dobb's Journal