919 research outputs found
Surface drilling technologies for Mars
Rock drilling and coring conceptual designs for the surface activities associated with a manned Mars mission are proposed. Straightforward extensions of equipment and procedures used on Earth are envisioned for the sample coring and shallow high explosive shot holes needed for tunneling and seismic surveying. A novel rocket exhaust jet piercing method is proposed for very rapid drilling of shot holes required for explosive excavation of emergency radiation shelters. Summaries of estimated equipment masses and power requirements are provided, and the indicated rotary coring rigs are scaled from terrestrial equipment and use compressed CO2 from the Martian atmosphere for core bit cooling and cuttings removal. A mass of 120 kg and power of 3 kW(e) are estimated for a 10 m depth capability. A 100 m depth capacity core rig requires about 1150 kg and 32 km(e). The rocket exhaust jet equipment devised for shallow (3m) explosive emplacement shot holes requires no surface power beyond an electrical ignition system, and might have a 15 kg mass
The Economics of Giving: How Monetary Policy Impacts Charitable Giving
This paper examines the impact of the monetary policy transmission mechanism specifically the Loan Supply (Narrow Credit Channel), Market Interest Rates (Interest Rate Channel) and Asset Price Levels (Wealth Channel) have on charitable giving within the United States. An OLS (Ordinary Least Squares) model is used to test whether the variables within each channel influences charitable giving. We find that each variable used (revolving credit, real estate loans, federal funds rate, inflation, real disposable income and housing prices) is statistically significant in influencing charitable giving within the United States
Influence of Spatially Variable Instrument Networks on Climatic Averages
Copyright 1991 by the American Geophysical Union.Instrument networks for measuring surface air temperature (T) and precipitation (P) have varied considerably over the last century. Inadequate observingâstation locations have produced incomplete, uneven, and biased samples of the spatial variability in climate and, in turn, terrestrial and global scale averages of T and P have been biased. New highâresolution climatologies [Legates and Willmott, 1990a; 1990b] are intensively sampled and integrated to illustrate the effects of these nontrivial sampling biases. Since station networks may not represent spatial climatic variability adequately, their ability to represent climate through time is suspect
Internationalizing A Business School Program: A Descriptive Study Of A Strategic Implementation Process Of Internationalization
The purpose of this study is to explain the process that a small private business school with limited resources and no prior experience took to internationalize its business school program. The extent of this globalization project was not limited to just revising, initiating, and enhancing its course offerings for accounting, business administration and economics major but it also included a plan to provide additional Study Abroad opportunities for its business students, to develop collaborative partnerships with the Spanish foreign language faculty, and to increase educational programs to the outside business communities. All of these will be briefly explained because this globalization process would be incomplete without their inclusion; however, the focus of this particular study will concentrate on the internationalization of the business school curriculum
Zeeman Relaxation of Cold Atomic Iron and Nickel in Collisions with 3He
We have measured the ratio of the diffusion cross-section to the angular
momentum reorientation cross-section in the colliding Fe-3He and Ni-3He
systems. Nickel (Ni) and iron (Fe) atoms are introduced via laser ablation into
a cryogenically cooled experimental cell containing cold (< 1 K) 3He buffer
gas. Elastic collisions rapidly cool the translational temperature of the
ablated atoms to the helium temperature. The cross-section ratio is extracted
by measuring the decays of the atomic Zeeman sublevels. For our experimental
conditions, thermal energy is comparable to the Zeeman splitting. As a result,
thermal excitations between Zeeman sublevels significantly impact the observed
decay. To determine the cross-section ratio accurately, we introduce a model of
Zeeman state dynamics that includes thermal excitations. We find the
cross-section ratio for Ni-3He = 5 x 10^3 and Fe-3He <= 3 x 10^3 at 0.75 K in a
0.8 T magnetic field. These measurements are interpreted in the context of
submerged shell suppression of spin relaxation as studied previously in
transition metals and rare earth atoms.Comment: 10 pages, 5 figures; submitted to Phys. Rev.
Directly pumped 10ââGHz microcomb modules from low-power diode lasers
Soliton microcombs offer the prospect of advanced optical metrology and timing systems in compact form factors. In these applications, the pumping of microcombs directly from a semiconductor laser without amplification or triggering components is desirable to reduce system power and to simplify system design. At the same time, low-repetition-rate microcombs are required in many comb applications as an interface to detectors and electronics, but their increased mode volume makes them challenging to pump at low power. Here 10 GHz repetition rate soliton microcombs are directly pumped by low-power (<20ââmW) diode lasers. High-Q silica microresonators are used for this low-power operation and are packaged into fiber-connectorized modules that feature temperature control for improved long-term frequency stability
Age-Differentiated Leadership and Healthy Aging at Work: Evidence from the Early Stages of the COVID-19 Pandemic
Little is known about the relative influence of age-differentiated leadership on healthy aging at work. Likewise, the age-conditional influence of age-differentiated leadership is understudied, and especially so in the context of the COVID-19 pandemic. Using a three-wave longitudinal study, we examined the role that age-differentiated leadership plays in the prediction of work ability, as measured three times over six months (n = 1130) during the early stages of the COVID-19 pandemic in Germany (i.e., December 2019, March 2020, and June 2020). The results suggest that although there were no systematic changes in work ability on average, there was notable within-person variability in work ability over time. Additionally, we find that a balanced approach to age-differentiated leadership that considers the needs of both older and younger employees matters most and complements the positive influence of leaderâmember exchange for predicting within-person variability in work ability. We also find that older employeesâ work ability benefits from an approach to age-differentiated leadership that considers older employeeâs needs, whereas younger employeesâ work ability especially benefits from leaderâmember exchange and a balanced approach to age-differentiated leadership. Overall, these results provide initial support for the idea that an age-differentiated approach to leadership is important when considering healthy aging at work
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Spousal Communication in the Family Setting (Married with Children)
Communication plays an important role in the life
of a couple. This study seeks to determine the nature of
couple communication. This study compares and contrasts
the differences and similarities in communication between
childless couples and parenting couples. The material
for this study comes from interviewing ten married
couples along with their responses to a written
instrument.
This study tries to answer the following questions:
Is there a difference in communication between couples
who have children and those who do not?
Does the content of communication vary if the couple
is parenting or not?
Is the communication pattern of parents unique enough
to be assigned individual characteristics?
How do the couples themselves describe their
communication
A.A.L.S. Clinical Legal Education Panel: Evaluation and Assessment of Student Performance in a Clinical Setting
This article is adapted from a panel discussion held under the auspices of the Section on Clinical Legal Education of the Association of American Law Schools, presented at the annual meeting in Phoenix, Arizona on January 5, 1980. The participants were H. Russell Cort, Jack L. Sammons, Robert S. Catz, Ralph S. Tyler and Terence J. Anderson
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