3,068 research outputs found
Space Missions for Automation and Robotics Technologies (SMART) Program
NASA is currently considering the establishment of a Space Mission for Automation and Robotics Technologies (SMART) Program to define, develop, integrate, test, and operate a spaceborne national research facility for the validation of advanced automation and robotics technologies. Initially, the concept is envisioned to be implemented through a series of shuttle based flight experiments which will utilize telepresence technologies and real time operation concepts. However, eventually the facility will be capable of a more autonomous role and will be supported by either the shuttle or the space station. To ensure incorporation of leading edge technology in the facility, performance capability will periodically and systematically be upgraded by the solicitation of recommendations from a user advisory group. The facility will be managed by NASA, but will be available to all potential investigators. Experiments for each flight will be selected by a peer review group. Detailed definition and design is proposed to take place during FY 86, with the first SMART flight projected for FY 89
Flight elements: Fault detection and fault management
Fault management for an intelligent computational system must be developed using a top down integrated engineering approach. An approach proposed includes integrating the overall environment involving sensors and their associated data; design knowledge capture; operations; fault detection, identification, and reconfiguration; testability; causal models including digraph matrix analysis; and overall performance impacts on the hardware and software architecture. Implementation of the concept to achieve a real time intelligent fault detection and management system will be accomplished via the implementation of several objectives, which are: Development of fault tolerant/FDIR requirement and specification from a systems level which will carry through from conceptual design through implementation and mission operations; Implementation of monitoring, diagnosis, and reconfiguration at all system levels providing fault isolation and system integration; Optimize system operations to manage degraded system performance through system integration; and Lower development and operations costs through the implementation of an intelligent real time fault detection and fault management system and an information management system
Density fluctuations and the structure of a nonuniform hard sphere fluid
We derive an exact equation for density changes induced by a general external
field that corrects the hydrostatic approximation where the local value of the
field is adsorbed into a modified chemical potential. Using linear response
theory to relate density changes self-consistently in different regions of
space, we arrive at an integral equation for a hard sphere fluid that is exact
in the limit of a slowly varying field or at low density and reduces to the
accurate Percus-Yevick equation for a hard core field. This and related
equations give accurate results for a wide variety of fields
An emerging opportunistic infection: fatal animal-astrovirus encephalitis in a paediatric stem cell transplant recipient
Overview of Highland Valley Tailings Storage Facility
This paper presents key features of the Highland Valley tailings storage facility comprising two tailings dams, a 107 m high H-H Dam and a 166 m high L-L Dam. The construction history to date including instrumentation observations is also reviewed. Although the tailings facility is situated in a low to moderate seismic area within the Interior Plateau of British Columbia, potential earthquake sources that might have an impact on the site have been carefully assessed. Both dams are designed to have adequate seismic resistance against design earthquakes appropriate for the site. The L-L Dam valley section, involving soft lacustrine deposits beneath the Starter Dam, has been buttressed by a compacted downstream berm founded on dense glacial till. As the geometry of the tailings storage and distribution facilities and waste dumps changes with time, the quantity and relative cost of various construction materials including natural borrow, cycloned sand and pit overburden also change. Ongoing construction is planned to maintain key earthquake and flood design criteria as well as to adjust the use and placement method of various materials to achieve an efficient and cost effective tailings storage operation. Inherent in the design of the two tailings dams, both constructed by the centerline method, is the flexibility which enables the storage capacity of the tailings facility to be increased beyond the present 1.8 billion tonnes if required at some future time
Audit Costs for the 1986 Texas Energy Cost Containment Program
Direct program costs for detailed audits of
13.5 million square feet of institutional building
space in the 1986 Texas Energy Cost Containment
Program were 0.050/SF. Large medical buildings (greater
than about 170,000 square feet) were audited for
0.0028/SF. The effect on audit costs of
complexity of recommended modifications, amount of
savings determined, amount of implementation
costs, building size, and building complexity are
discussed. Primary effects on audit costs are
size and complexity of buildings. Program
guidelines limited consideration of projects with
greater than a four year payback
Wigs, disguises and child's play : solidarity in teacher education
It is generally acknowledged that much contemporary education takes place within a dominant audit culture, in which accountability becomes a powerful driver of educational practices. In this culture both pupils and teachers risk being configured as a means to an assessment and target-driven end: pupils are schooled within a particular paradigm of education. The article discusses some ethical issues raised by such schooling, particularly the tensions arising for teachers, and by implication, teacher educators who prepare and support teachers for work in situations where vocational aims and beliefs may be in in conflict with instrumentalist aims. The article offers De Certeau’s concept of ‘la perruque’ to suggest an opening to playful engagement for human ends in education, as a way of contending with and managing the tensions generated. I use the concept to recover a concept of solidarity for teacher educators and teachers to enable ethical teaching in difficult times
Robust Upward Dispersion of the Neutron Spin Resonance in the Heavy Fermion Superconductor CeYbCoIn
The neutron spin resonance is a collective magnetic excitation that appears
in copper oxide, iron pnictide, and heavy fermion unconventional
superconductors. Although the resonance is commonly associated with a
spin-exciton due to the ()-wave symmetry of the superconducting
order parameter, it has also been proposed to be a magnon-like excitation
appearing in the superconducting state. Here we use inelastic neutron
scattering to demonstrate that the resonance in the heavy fermion
superconductor CeYbCoIn with has a ring-like
upward dispersion that is robust against Yb-doping. By comparing our
experimental data with random phase approximation calculation using the
electronic structure and the momentum dependence of the -wave
superconducting gap determined from scanning tunneling microscopy for
CeCoIn, we conclude the robust upward dispersing resonance mode in
CeYbCoIn is inconsistent with the downward dispersion
predicted within the spin-exciton scenario.Comment: Supplementary Information available upon reques
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