Scientists often use the "slingshot effect" (also called the "gravity assist") of the gravitational field of a planet to increase or decrease the velocity of a spacecraft. Examples of this effect, puzzling aspects, a qualitative explanation, details of necessary calculations, a thermodynamic analogy, and other topics are discussed. (JN)

Effective navigation is becoming more and more critical to the success of electronic commerce (E-commerce). It remains a challenge for educational technologists and Web designers to develop Web systems that can help customers find products or services without experiencing disorientation problems and cognitive overload. Many E-commerce Web sites…

Discusses navigation in instructional hypertext programs and describes two preliminary studies that investigated concrete versus abstract representations for backward navigation. Topics include representation and hypermedia sign systems; and consistency in the forms designers use for navigation buttons. (LRW)

Tracks the development of sonar from a submarine detecting device to a seabed plotting device. Describes applications of the technology in fishing and oceanography. (MDH)

Sixth graders at Kamehameha Elementary School ascended a high mountain peak, successfully orienting themselves for over 5 miles using topographical maps and compasses and the knowledge, skills, and attitudes acquired at school. The article describes the program, noting the knowledge and tools students used to accomplish their goal. (SM)

Provides a knowledge representation frame for describing walking directions on a university campus. Directional and nondirectional content of messages that were sent by either electronic mail or voice messaging are examined; sublanguage techniques used to analyze messages are explained; and future work is discussed. (nine references) (LRW)

Discusses aspects of Christopher Columbus' decision to sail west in order to reach Asia. Includes discussions concerning the shape and size of the earth as determined up to Columbus' time and conclusions he made during the journey based on his calculations. (MDH)

Discusses the use of document outlines to reduce navigation problems in hypertext. Measures of syntactic and lexical balance in an outline are proposed, and the degree to which these balances occur in a sample of documents is shown. Based on balance in an outline, a method for semiautomatically generating an outline is applied to a textbook. (45…

Presents a texture-based image-retrieval system for browsing large-scale aerial photographs. System components include texture-feature extraction, image segmentation and grouping, learning-similarity measure, and a texture-thesaurus model for fast search and indexing. Testing has demonstrated the system's effectiveness in searching and selecting…

Discusses user interaction with museum application interfaces and emphasizes the importance of adaptable and adaptive interfaces to meet differing user needs. Considers levels of support that can be given to different users during navigation of museum hypermedia information, using examples from the Web site for the Marble Museum (Italy).…

This study investigates the relationships between undergraduate hypermedia users' information processing styles and navigational patterns. Discusses use of the Human Information Processing Survey, learning styles and information processing styles, and brain hemisphericity. Results show a significant relationship between information processing…

Explains the development of a classification system for different types of icons to determine which icons proved difficult for elementary school students to read. Considers pictorial, textual, and combination icons from two CD-ROM programs, and concludes that assumptions about pictorial navigation icons and benefits of pop-up labels are probably…

Describes a study of undergraduates that examined the effects of the cognitive load associated with using hypertext linking capabilities in instructional materials. Highlights include cognitive flexibility theory; hypertext navigation; results of criterion measures and regression analysis; and cognitive load theory. (Contains 56 references.) (LRW)

Describes confluent presentation strategy (CPS) (i.e., a philosophy for developing student-centered, user/computer interfaces) and discusses its use to minimize student disorientation when using interactive computer-based training programs. Instructional design for computer interfaces and navigation are discussed, and an example of a CD-ROM that…