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The design of a Martian autonomous rotary wing vehicle (MARV) is described. MARV is a 50-kg gross takeoff mass, coaxial helicopter designed for Mars exploration. Powered by a fuel cell system, it carries a payload of 10.8 kg over a range of 25 km with an endurance of 39 min including hover capability for 1 min. MARV is designed in response to the Request For Proposal from NASA/Sikorsky for the Year 2000 American Helicopter Society student design competition. The design covers aerodynamic and structural design of rotor blades, vehicle power plant, fuselage and landing gear, control system, transmission, and vehicle lander communications. A detailed mechanism for autonomous deployment of the vehicle from the lander is also described. This preliminary design study indicates that controlled vertical ight on Mars is feasible with existing technology.

This article examines one approach to theory and research that has recently cut across a number of different fields of inquiry in physical and social sciences, linguistics, and literature. The literature on chaos theory or chaotic systems modeling was reviewed, and some general concepts that characterize this research approach developed from the review. Chaotic systems concepts then were used to analyze a case study of rapid growth and conflict in a school district in search of insight into the utility of chaotic modeling for research in educational administration. The authors conclude that difficulties arising from the need for very precise initial measurements, data in forms that lend themselves to pattern modeling, and precise meanings for chaotic systems concepts limit its application to research in educational administration.

The mode of scientific inquiry that was dominant in the 1950s and early 1960s is described, and the work of four prominent sets of researchers of that period is analyzed in an effort to determine the degree to which the research that was conducted actually followed the tenets of the prevailing philosophy. Then, the much more complicated conditions of the present are examined in the light of the multiple, divergent, and conflicting ideologies that are now being espoused. Four currently prominent sets of researchers are selected, and both the theoretical and methodological characteristics of their efforts are assessed. The general conclusion of the analysis is that the researchers of the present are ignoring the criticisms of functionalism as well as the new approaches being advocated, and they are still working loosely within the framework of logical positivism.

In this paper, the author begins with the proposition that research and theory tend to lag behind practice in educational administration. By this he means that the problems of schools, and the activities of administrators, teachers, students and parents are not adequately explained by present theories nor examined successfully by present-day research. In addition, while there seems to be a general awareness of the social milieu in which the school exists, theory and research in educational administration do not reflect the social setting of education. There are many reasons for this, including faulty research methodology. In exploring this claim the author makes the case for theoretical pluralism and does so by attempting to demonstrate the shortcomings of research based on single theories. He claims that practitioners have always complained that research has not helped them to do a better job and suggests that theoretical pluralism offers the best hope of remedying this.