Models of the earth's electric field

Detailed models of the electric field of the magnetosphere are derived in several stages. For all, the conductivity along field lines is assumed to be high enough to ensure the vanishing of E B everywhere except in the ionosphere. At first the rotation of the earth is ignored completely and a simple model is constructed which fits certain observed properties. Next, the rotation of the earth is taken into account, but the field is assumed to be that of a magnetic dipole rotating around its symmetry axis. This allows the concept of the electric potential to be retained, which permits the derivation of interesting properties including the use of a conjugate potential which paces the drift of charged particles in the field. Finally, the general case involving asymmetrical rotation is briefly discussed

An Introduction to Magnetospheric Physics by Means of Simple Models

The large scale structure and behavior of the Earth's magnetosphere is discussed. The model is suitable for inclusion in courses on space physics, plasmas, astrophysics or the Earth's environment, as well as for self-study. Nine quantitative problems, dealing with properties of linear superpositions of a dipole and a constant field are presented. Topics covered include: open and closed models of the magnetosphere; field line motion; the role of magnetic merging (reconnection); magnetospheric convection; and the origin of the magnetopause, polar cusps, and high latitude lobes

Solar Terrestrial programs: A five year plan

Major projects to be initiated in the 1980-1985 period, designed to study the Sun, the heliosphere, Earth's magnetosphere, and the upper atmosphere involve the use of spacelab as well as free flying spacecraft. Current and recent investigations in these areas are reviewed and the guiding principles followed in planning future missions are examined. The implementation strategy, the planning process, and supporting research and technology are discussed

The canonization of nice variables

Canonization of nice variable

The Other Pathway To The Boardroom: Interpersonal Influence Behavior As A Substitute For Elite Credentials And Majority Status In Obtaining Board Appointments

Using survey data on interpersonal influence behavior from a large sample of managers and chief executive officers (CEOs) at Forbes 500 companies, we examine how ingratiatory behavior directed at individuals who control access to board positions can provide an alternative pathway to the boardroom for managers who lack the social and educational credentials associated with the power elite. Findings show that top managers who engage in ingratiatory behavior toward their CEO, with ingratiation comprising flattery, opinion conformity, and favor-rendering, will be more likely to receive board appointments at other firms where their CEO serves as director and at boards to which the CEO is indirectly connected in the board interlock network. Further results suggest that interpersonal influence behavior substitutes to some degree for the advantages of an elite background or demographic majority status. Our findings help explain why norms of director deference to CEOs have persisted despite increased diversity in the corporate elite and have implications for research on corporate governance, social networks in the corporate elite, and for the sociological question of whether demographic minorities and individuals who lack privileged backgrounds have equal access to positions of leadership in large U.S. companies. Our study ultimately suggests that such individuals face a rather subtle and perhaps unexpected form of social discrimination, in that they must engage in a higher level of interpersonal influence behavior in order to have the same chance of obtaining a board appointment.Managemen

A brushless dc spin motor for momentum exchange altitude control

Brushless dc spin motor is designed to use Hall effect probes as means of revolving rotor position and controlling motor winding currents. This results in 3 to 1 reduction in watt-hours required for wheel acceleration, a 2 to 1 reduction in power to run wheel, and a 10 to 1 reduction in the electronics size and weight

Selection-Based Learning: The Coevolution Of Internal And External Selection In High-Velocity Environments

To understand the effects of selection on firm-level learning, this study synthesizes two contrasting views of evolution. Internal selection theorists view managers in multiproduct firms as the primary agents of evolutionary change because they decide whether individual products and technologies are retained or eliminated. In contrast, external selection theorists contend that the environment drives evolution because it determines whether entire firms live or die. Though these theories differ, they describe tightly interwoven processes. In assessing the coevolution of internal and external selection among personal computer manufacturers across a 20-year period, we found that (1) firms learned cumulatively and adaptively from internal and partial external selection, the latter occurring when the environment killed part but not all of a firm; (2) internal and partial external selection coevolved, as each affected the other's future rate and the odds of firm failure; (3) partial external selection had a greater effect on future outcomes than internal selection; and (4) the lessons gleaned from prior selection were reflected in a firm's ability to develop new products, making that an important mediator between past and future selection events.Managemen