A study of institutional change: Faculty reactions to a change from a quarter to a semester calendar

This study represents the first phase of a projected five-year institutional research project at Iowa State University. It was designed to assess the change in stated faculty perceptions of the learning environment under quarter and semester calendars along with changes in perception of calendar transition and general academic environment between spring 1981 and spring 1982. ISU shifted from a quarter to semester program in fall 1981;Faculty involvement in decisions on shifts in the calendar was emphasized in a summary of calendar changes since the late 1800s and a chronology of events taking place just prior to the change and during the implementation of the new calendar. Research observations were compared to the literature on academic change;Data from questionnaires sent to faculty in April 1981 and again in April 1982 were analyzed using t tests to assess differences between years on 15 factor variables. Significant differences between years in most cases showed a shift toward the mean or more neutral response rather than a change in direction. On the ten factors where significant differences occurred, ANOVAs were computed between the mean difference scores (1981 minus 1982) and independent variables which included: college, rank, type of appointment, sex, years at ISU, years at other institutions, voting incidence, direction of vote, faculty assignment and curriculum committee participation. Whether faculty voted for or against the change produced the largest number of differences. Faculty who voted against the change responded more negatively to the change and the learning environment as they anticipated it would be under the semester system (1981 response before the change) and as they reported finding it in spring 1982

Digital Alchemy for Materials Design: Colloids and Beyond

Starting with the early alchemists, a holy grail of science has been to make desired materials by modifying the attributes of basic building blocks. Building blocks that show promise for assembling new complex materials can be synthesized at the nanoscale with attributes that would astonish the ancient alchemists in their versatility. However, this versatility means that making direct connection between building block attributes and bulk behavior is both necessary for rationally engineering materials, and difficult because building block attributes can be altered in many ways. Here we show how to exploit the malleability of the valence of colloidal nanoparticle "elements" to directly and quantitatively link building block attributes to bulk behavior through a statistical thermodynamic framework we term "digital alchemy". We use this framework to optimize building blocks for a given target structure, and to determine which building block attributes are most important to control for self assembly, through a set of novel thermodynamic response functions, moduli and susceptibilities. We thereby establish direct links between the attributes of colloidal building blocks and the bulk structures they form. Moreover, our results give concrete solutions to the more general conceptual challenge of optimizing emergent behaviors in nature, and can be applied to other types of matter. As examples, we apply digital alchemy to systems of truncated tetrahedra, rhombic dodecahedra, and isotropically interacting spheres that self assemble diamond, FCC, and icosahedral quasicrystal structures, respectively.Comment: 17 REVTeX pages, title fixed to match journal versio

Paper Session II-A - Lockheed Martin\u27s Next Generation Launch Systems

The space launch industry is experiencing a tremendous transition from a government dominated customer base to a commercial customer base. According to the Teal Group World Space Briefing, nearly 75 percent of satellites launched from 1997 to 2006 will be civil and commercial satellites (figure 1). Of these, the vast majority are commercial ventures in mobile communications, broadband multi-media services, or direct broadcast television satellites. Nearly three quarters of all proposed payloads are destined for Low Earth Orbit (LEO). Virtually all LEO satellites will belong to multi-satellite systems involving mobile communications or multimedia services. Lockheed Martin is a world leader in the expendable launch vehicle industry. Our heritage which began with the Titan and Atlas launch systems in the late 1950’s, has spanned four decades and over 1,000 launches. In the late 1980’s, the former General Dynamics Space Systems (GD), recognized the need to develop a launch vehicle that could compete in the international commercial market. In 1987, GDinitiated the first commercial launch vehicle, the Atlas II. TheAtlas vehicle has successfully evolved from II to IIA to IIAS and into today’s newest most powerful system yet - the Atlas IIAR which will be operational in late 1998. The driving force behind each system upgrade has been to improve performance while reducing cost and increasing reliability. Lockheed Martin combined the commercial industry expertise of the Atlas program with the heritage hardware of both the Atlas and Titan programs to develop their next generation launch vehicle the Common Core BoosterTM family. The Common Core BoosterTM family of launch vehicles will accommodate a wide range of customers, by providing a highly reliable, responsive system with streamlined launch operations. The Common Core BoosterTM vehicle allows Lockheed Martin tol effectively compete in international commercial markets, while satisfying the United States government requirements for low cost, reliable access to space. The purpose of this paper is to describe Lockheed Martin’s approach to incorporating the benefits and lessons learned from the Atlas and Titan launch systems into a launch vehicle family that will serve the payload community well into the 21st Century

Stability of an Erratic Tailings Deposit

150 million cubic meters of erratic colliery spoils were deposited between 1971 and 1983 close to the Kardia lignite fields, in Greece. The heap finally reached satisfactorily an escalating height of 73 m. Field reconnaissance, collation of local experience and geotechnical investigations were performed during midstage of deposition. They aimed at an optimal configuration of the fill in progress, within the possibilities allowed by extensive earth moving operations. Present paper out- 1ines the approach and the methodology used to arrive at strength parameters and slope design of a highly inhomogeneous massive comprising variegated soils, marls and encaptured lignites

Line Emission from an Accretion Disk around a Rotating Black Hole: Toward a Measurement of Frame Dragging

Line emission from an accretion disk and a corotating hot spot about a rotating black hole are considered for possible signatures of the frame-dragging effect. We explicitly compare integrated line profiles from a geometrically thin disk about a Schwarzschild and an extreme Kerr black hole, and show that the line profile differences are small if the inner radius of the disk is near or above the Schwarzschild stable-orbit limit of radius 6GM/c^2. However, if the inner disk radius extends below this limit, as is possible in the extreme Kerr spacetime, then differences can become significant, especially if the disk emissivity is stronger near the inner regions. We demonstrate that the first three moments of a line profile define a three-dimensional space in which the presence of material at small radii becomes quantitatively evident in broad classes of disk models. In the context of the simple, thin disk paradigm, this moment-mapping scheme suggests formally that the iron line detected by the Advanced Satellite for Cosmology and Astrophysics mission from MCG-6-30-15 (Tanaka et al. 1995) is 3 times more likely to originate from a disk about a rotating black hole than from a Schwarzschild system. A statistically significant detection of black hole rotation in this way may be achieved after only modest improvements in the quality of data. We also consider light curves and frequency shifts in line emission as a function of time for corotating hot spots in extreme Kerr and Schwarzschild geometries. Both the frequency-shift profile and the light curve from a hot spot are valuable measures of orbital parameters and might possibly be used to detect frame dragging even at radii approaching 6GM/c^2 if the inclination angle of the orbital plane is large.Comment: 15 pages (LaTex), 7 postscript figures; color plot (Figure 1) available at http://cfata2.harvard.edu/bromley/nu_nofun.html (This version contains a new subsection as well as minor corrections.