Design of the materials experiment carrier for on-orbit servicing

This paper discussed the MEC system and its mission from the viewpoint of orbit servicing. Information is provided on MEC system requirements, design for on orbit servicing, on orbit servicing operations and rationale and servicing costs

The Potential of Space Manufacturing

This paper defines space manufacturing, then discusses the potential processes and product types that are implied in the definition. Both current government early planning and commercial industry formulative thinking contribute to the definition. How quickly space processing or space productization occurs is directly tied to critical technologies, legal implications, and business incentives. A roadmap to space manufacturing is offered. It sets forth the time phased events that must occur in the near term 1982-1987 to cause space manufacturing to be commercially profitable in the 1990\u27s. The key to any attempt at scoping the promise of space manufacturing is the timely involvement of the private sector in space activities. The cornerstone of this involvement is the need for strong government commitment, backed by funding, to the concept of promoting United States commercialization of space for national benefits

Changes in ponderosa pine forests of the Mt. Logan Wilderness.

Ponderosa pine forests in the Mt. Logan Wilderness on the Arizona Strip have become dense with young trees and highly susceptible to catastrophic wildfire due to exclusion of the natural frequent-fire regime and the effects of livestock grazing and logging associated with Euro-American land use practices. As part of a broader regional ecological restoration study, the Mt. Logan Wilderness was sampled for fire scarred trees, vegetation, and fuels between 1995 and 1997. Reconstructed fire histories show that fires recurred about every 5-6 years prior to settlement, with larger fires burning every 9-12 years. Frequent fires ceased after 1869-1879 in the Mt. Logan Wilderness, coincident with the time of Euro-American settlement, beginning a fire-free period that has lasted up to the present except for a few fires in the 1930s. Current forests are dense, ranging from approximately 700 to 3,000 trees/ha, and dominated by small trees. At both unthinned and thinned sites on basalt soils within the wilderness, tree canopy cover is over 50(percent) and tree basal area is high, 39-40 m2/ha. Understory cover and species diversity are generally low, but slightly higher on cinder soils where shrubs form an important understory community and where tree density is somewhat reduced. Living and dead fuels, including plants, woody debris, and the forest floor , will easily support high-intensity wildfires. In contrast, the presettlement forest was relatively open, with tree densities ranging from approximately 80-100 trees/ha and basal areas ranging from 10-15 m2/ha, dominated by large ponderosa pine trees. In ecological terms, prospects are good for restoring the Mt. Logan Wilderness to emulate the ecological structure and fire disturbance regime of the presettlement reference condition. The current forest is similar to nearby ecosystems where thinning, burning, and fuel treatments are being implemented. However, ecological information is only one component contributing to the debate over appropriate management values and practices in wilderness areas on public lands

Activating Library Classrooms: Evaluating Formal Learning Spaces for Active Learning and Student Engagement

Funded by the Association of College & Research Libraries through a 2018 Academic Library Impact Research Grant, the Activating Library Classrooms: Evaluating Formal Learning Spaces for Active Learning and Student Engagement project endeavored to evaluate the design and use of formal learning spaces situated within X X University Libraries. Researchers evaluated seven library classrooms and interviewed seven faculty collaborators at six X X University campuses in order to identify areas of strength and growth for formal learning spaces. The results affirm the significance of formal learning spaces in libraries and how they can demonstrate academic libraries’ ability to partner in university curricula and student success

Probability and magnitude evaluation in schizophrenia

Alterations in reinforcement learning and decision making in schizophrenia have been linked with orbitofrontal cortex (OFC) dysfunction, a region critical for weighing reward magnitude in the calculation of expected value (EV). However, much of this work has used complex tasks that require combined learning and EV calculation. Here we used a simple “Roulette” task that examined the calculation of EV directly through a combination of text and/or pictorial representation of reward probability and magnitude. Forty-four people with schizophrenia and 30 controls were recruited. Patients were less sensitive to adjustments in a parameter combining probability and magnitude into one EV construct. Breaking down the construct into independent contributions of probability and magnitude, we found that negative symptoms were associated with magnitude sensitivity. This is consistent with the hypothesized role of OFC in actively representing magnitude and the notion that negative symptoms may involve a failure to appropriately estimate and use future reward magnitude to guide decision making

Morphology control of zinc oxide films via polysaccharide-mediated, low temperature, chemical bath deposition

In this study we present a three-step process for the low-temperature chemical bath deposition of crystalline ZnO films on glass substrates. The process consists of a seeding step followed by two chemical bath deposition steps. In the second step (the first of the two bath deposition steps), a natural polysaccharide, namely hyaluronic acid, is used to manipulate the morphology of the films. Previous experiments revealed a strong influence of this polysaccharide on the formation of zinc oxide crystallites. The present work aims to transfer this gained knowledge to the formation of zinc oxide films. The influence of hyaluronic acid and the time of its addition on the morphology of the resulting ZnO film were investigated. By meticulous adjustment of the parameters in this step, the film morphology can be tailored to provide an optimal growth platform for the third step (a subsequent chemical bath deposition step). In this step, the film is covered by a dense layer of ZnO. This optimized procedure leads to ZnO films with a very high electrical conductivity, opening up interesting possibilities for applications of such films. The films were characterized by means of electron microscopy, X-ray diffraction and measurements of the electrical conductivity.BMB