Reliability achievement in high technology space systems

The production of failure-free hardware is discussed. The elements required to achieve such hardware are: technical expertise to design, analyze, and fully understand the design; use of high reliability parts and materials control in the manufacturing process; and testing to understand the system and weed out defects. The durability of the Hughes family of satellites is highlighted

Microprobe studies of microtomed particles of white druse salts in shergottite EETA 79001

The white druse material in Antarctic shergottite EETA 79001 has attracted much attention as a possible sample fo Martian aqueous deposits. Instrumental Neutron Activation Analysis (INAA) was used to determine trace element analyses of small particles of this material obtained by handpicking of likely grains from broken surfaces of the meteorite. Electron microprobe work was attempted on grain areas as large as 150x120 microns. Backscattered electron images show considerable variations in brightness, and botryoidal structures were observed. Microprobe analyses showed considerable variability both within single particles and between different particles. Microtomed surfaces of small selected particles were shown to be very useful in obtaining information on the texture and composition of rare lithologies like the white druse of EETA 79001. This material is clearly heterogeneous on all distance scales, so a large number of further analyses will be required to characterize it

Discrete ordinates-Monte Carlo coupling: A comparison of techniques in NERVA radiation analysis

In the radiation analysis of the NERVA nuclear rocket system, two-dimensional discrete ordinates calculations are sufficient to provide detail in the pressure vessel and reactor assembly. Other parts of the system, however, require three-dimensional Monte Carlo analyses. To use these two methods in a single analysis, a means of coupling was developed whereby the results of a discrete ordinates calculation can be used to produce source data for a Monte Carlo calculation. Several techniques for producing source detail were investigated. Results of calculations on the NERVA system are compared and limitations and advantages of the coupling techniques discussed

From Community College Faculty to Dean: Using Schlossberg’s Transition Theory to Understand the Transition Experience.

Succession planning and the pending vacancies in leadership are both important topics in higher education in general and community colleges specifically. Faculty have historically played an important role in filling the leadership pipeline in community colleges, with the first step in this transition being from faculty to academic deans. However, there is little research focused on the role of the academic dean, let alone that transition from faculty to administration, in the community college setting. The purpose of this qualitative study was to understand the perceptions of faculty who have transitioned into academic dean roles on two-year college campuses. Through the interviews with the seven participants, we began to understand how one perceives the transition from faculty to administrator in the community college setting. Schlossberg’s transition theory (1981) was the theoretical framework that was used and modified to create the four major factors labeled the Four S\u27s, in an attempt to understand an individual’s capacity to transition (Goodman, 2006; Schlossberg, 2008; Schlossberg, Lynch, & Chickering, 1989). This study found there is a wide range of motivations that prompt faculty to move into administration. Two themes emerged around the perceptions of the transition. The first was the fast-paced nature of the change, and the second was the changing relationship with faculty members. The participants were able to use their assets of situation, self, and strategies to overcome the liabilities of support to move into their new role. Implications for practice include: building a support system for new deans, developing practical training for deans, creating a greater sense of community among deans, and encouraging self-care

The deformed M2-brane

The superembedding formalism is used to study correction terms to the dynamics of the M2 brane in a flat background. This is done by deforming the standard embedding constraint. It is shown rigorously that the first such correction occurs at dimension four. Cohomological techniques are used to determine this correction explicitly. The action is derived to quadratic order in fermions, and the modified \k-symmetry transformations are given.Comment: 38 pages, 3 figure

Optimization of resource allocation can explain the temporal dynamics and honesty of sexual signals

In species in which males are free to dynamically alter their allocation to sexual signaling over the breeding season, the optimal investment in signaling should depend on both a male’s state and the level of competition he faces at any given time. We developed a dynamic optimization model within a game‐theoretical framework to explore the resulting signaling dynamics at both individual and population levels and tested two key model predictions with empirical data on three‐spined stickleback (Gasterosteus aculeatus) males subjected to dietary manipulation (carotenoid availability): (1) fish in better nutritional condition should be able to maintain their signal for longer over the breeding season, resulting in an increasingly positive correlation between nutritional status and signal (i.e., increasing signal honesty), and (2) female preference for more ornamented males should thus increase over the breeding season. Both predictions were supported by the experimental data. Our model shows how such patterns can emerge from the optimization of resource allocation to signaling in a competitive situation. The key determinants of the honesty and dynamics of sexual signaling are the condition dependency of male survival, the initial frequency distribution of nutritional condition in the male population, and the cost of signaling

Electrolysis of simulated lunar melts

Electrolysis of molten lunar soil or rock is examined as an attractive means of wresting useful raw materials from lunar rocks. It requires only hat to melt the soil or rock and electricity to electrolyze it, and both can be developed from solar power. The conductivities of the simple silicate diopside, Mg CaSi2O6 were measured. Iron oxide was added to determine the effect on conductivity. The iron brought about substantial electronic conduction. The conductivities of simulated lunar lavas were measured. The simulated basalt had an AC conductivity nearly a fctor of two higher than that of diopside, reflecting the basalt's slightly higher total concentration of the 2+ ions Ca, Mg, and Fe that are the dominant charge carriers. Electrolysis was shown to be about 30% efficient for the basalt composition

Geochemistry of HASP, VLT, and other glasses from double drive tube 79001/2

The Apollo 17 double drive tube 79001/2 (station 9, Van Serg Crater) is distinctive because of its extreme maturity, abundance, and variety of glass clasts. It contains mare glasses of both high Ti and very low Ti (VLT) compositions, and highland glasses of all compositions common in lunar regolith samples: highland basalt (feldspathic; Al2O3 greater than 23 wt percent), KREEP (Al2O3 less than 23 wt percent, K2O greater than 0.25 wt percent), and low-K Fra Mauro (LKFM; Al2O3 less than 23 wt percent, K2O less than 0.25 wt percent). It also contains rare specimens of high-alumina, silica-poor (HASP), and ultra Mg glasses. HASP glasses contain insufficient SiO2 to permit the calculation of a standard norm, and are thought to be the product of volatilization during impact melting. They have been studied by electron microprobe major-element analysis techniques but have not previously been analyzed for trace elements. The samples analyzed for this study were polished grain mounts of the 90-160 micron fraction of four sieved samples from the 79001/2 core (depth range 2.3-11.5 cm). A total of 80 glasses were analyzed by SEM/EDS and electron microprobe, and a subset of 33 of the glasses, representing a wide range of compositional types, was chosen for high-sensitivity INAA. A microdrilling device removed disks (mostly 50-100 micron diameter, weighing approx. 0.1-0.5 micro-g) for INAA. Preliminary data reported here are based only on short counts done within two weeks of irradiation

A Battleground No More: Cosmopolitanism, the Culture Wars, and the Urban-Rural Divide in Ohio Elections, 2004-2020

Long a battleground state in presidential elections, Ohio trended toward the GOP in both 2016 and 2020. Despite losing the national popular vote, Trump secured the state’s electoral votes by comfortable margins in both elections, sparking the question of what explains this shift? We ground this question broadly in the realignment literature, testing two slightly overlapping theoretical viewpoints: geo-cultural and socioeconomic/cosmopolitanism. The geo-cultural viewpoint emphasizes the urban-rural divide in American politics, arguing that the culture is completely different on opposite ends of the urban-rural continuum, resulting in disparate election results. The socioeconomic/cosmopolitan viewpoint acknowledges that culture and social issues play a role in elections, but that the global economy of the 21st century drives results. To test these viewpoints, we use data on Ohio’s communities from the American Community Survey. Running spatial regressions, we find that there is evidence for both viewpoints present in Ohio over the past 20 years. Specifically, both Democrats and Republicans made gains in their geographic strongholds, but Democrats have made larger inroads in more cosmopolitan communities. However, Republicans made huge gains along the cultural dimension, giving them a strong advantage throughout the state. These results have implications for not only future presidential campaigns and how they target Ohio’s persuadable voters, but also for down ballot races in both the primary and general elections