3,665 research outputs found
Application of automobile emission control technology to light piston aircraft engines
The possibility was evaluated for achieving the EPA Standards for HC and CO emissions through the use of air-fuel ratio enleanment at selected power modes combined with improved air-fuel mixture preparation, and in some cases improved cooling. Air injection was also an effective approach for the reduction of HC and CO, particularly when combined with exhaust heat conservation techniques such as exhaust port liners
Emerging from the MIST: A Connector Tool for Supporting Programming by Non-programmers
Software development is an iterative process. As user re-quirements emerge software applications must be extended to support the new requirements. Typically, a programmer will add new code to an existing code base of an application to provide a new functionality. Previous research has shown that such extensions are easier when application logic is clearly separated from the user interface logic. Assuming that a programmer is already familiar with the existing code base, the task of writing the new code can be considered to be split into two sub-tasks: writing code for the application logic; that is, the actual functionality of the application; and writing code for the user interface that will expose the functionality to the end user.
The goal of this research is to reduce the effort required to create a user interface once the application logic has been created, toward supporting scientists with minimal pro-gramming knowledge to be able to create and modify pro-grams. Using a Model View Controller based architecture, various model components which contain the application logic can be built and extended. The process of creating and extending the views (user interfaces) on these model components is simplified through the use of our Malleable Interactive Software Toolkit (MIST), a tool set an infrastructure intended to simplify the design and extension of dynamically reconfigurable interfaces.
This paper focuses on one tool in the MIST suite, a connec-tor tool that enables the programmer to evolve the user interface as the application logic evolves by connecting related pieces of code together; either through simple drag-and-drop interactions or through the authoring of Python code. The connector tool exemplifies the types of tools in the MIST suite, which we expect will encourage collabora-tive development of applications by allowing users to inte-grate various components and minimizing the cost of de-veloping new user interfaces for the combined compo-nents
Tracing baryons in the warm-hot intergalactic medium with broad Ly alpha absorption
We discuss physical properties and baryonic content of broad Ly alpha
absorbers (BLAs) at low redshift. These absorption systems, recently discovered
in high-resolution, high-signal to noise quasar absorption line spectra,
possibly trace the warm-hot intergalactic medium (WHIM) in the temperature
range between 10^5 and 10^6 K. To extend previous BLA measurements we have
analyzed STIS data of the two quasars H 1821+643 and PG 0953+415 and have
identified 13 BLA candidates along a total (unblocked) redshift path of
dz=0.440. Combining our measurements with previous results for the lines of
sight toward PG 1259+593 and PG 1116+215, the resulting new BLA sample consists
of 20 reliably detected systems as well as 29 additional tentative cases,
implying a BLA number density of dN/dz=22-53. We estimate that the contribution
of BLAs to the baryon density at z=0 is Omega_b(BLA)>0.0027 h_70^-1 for
absorbers with log (N/b)>11.3. This number indicates that WHIM broad Ly alpha
absorbers contain a substantial fraction of the baryons in the local Universe.
(Abridged abstract)Comment: 17 pages, 7 figures; Accepted for publication in A&
Handbook for Learning-centred evaluation of Computer-facilitated learning projects in higher education
This handbook supports a project funded by the Australian Government Committee for University Teaching and Staff Development (CUTSD). The amended project title is “Staff Development in Evaluation of Technology-based Teaching Development Projects: An Action Inquiry Approach”.
The project is hosted by Murdoch University on behalf of the Australasian Society for Computers in Learning in Tertiary Education (ASCILITE), as a consortium of 11 universities.
The rationale of the project is to guide a group of university staff through the evaluation of a Computer-facilitated Learning (CFL1) project by a process of action inquiry and mentoring, supported by the practical and theoretical material contained in this handbook
The effects of multiple aerospace environmental stressors on human performance
An extended Fitt's law paradigm reaction time (RT) task was used to evaluate the effects of acceleration on human performance in the Dynamic Environment Simulator (DES) at Armstrong Laboratory, Wright-Patterson AFB, Ohio. This effort was combined with an evaluation of the standard CSU-13 P anti-gravity suit versus three configurations of a 'retrograde inflation anti-G suit'. Results indicated that RT and error rates increased 17 percent and 14 percent respectively from baseline to the end of the simulated aerial combat maneuver and that the most common error was pressing too few buttons
Scientists in the MIST: Simplifying Interface Design for End Users
We are building a Malleable Interactive Software Toolkit (MIST), a tool set and infrastructure to simplify the design and construction of dynamically-reconfigurable (malleable) interactive software. Malleable software offers the end-user powerful tools to reshape their interactive environment on the fly. We aim to make the construction of such software straightforward, and to make reconfiguration of the resulting systems approachable and manageable to an educated, but non-specialist, user. To do so, we draw on a diverse body of existing research on alternative approaches to user interface (UI) and interactive software construction, including declarative UI languages, constraint-based programming and UI management, reflection and data-driven programming, and visual programming techniques
The Large, Oxygen-Rich Halos of Star-Forming Galaxies Are A Major Reservoir of Galactic Metals
The circumgalactic medium (CGM) is fed by galaxy outflows and accretion of
intergalactic gas, but its mass, heavy element enrichment, and relation to
galaxy properties are poorly constrained by observations. In a survey of the
outskirts of 42 galaxies with the Cosmic Origins Spectrograph onboard the
Hubble Space Telescope, we detected ubiquitous, large (150 kiloparsec) halos of
ionized oxygen surrounding star-forming galaxies, but we find much less ionized
oxygen around galaxies with little or no star formation. This ionized CGM
contains a substantial mass of heavy elements and gas, perhaps far exceeding
the reservoirs of gas in the galaxies themselves. It is a basic component of
nearly all star-forming galaxies that is removed or transformed during the
quenching of star formation and the transition to passive evolution.Comment: This paper is part of a set of three papers on circumgalactic gas
observed with the Cosmic Origins Spectrograph on HST, to be published in
Science, together with related papers by Tripp et al. and Lehner & Howk, in
the November 18, 2011 edition. This version has not undergone final
copyediting. Please see Science online for the final printed versio
Feasibility study of an Integrated Program for Aerospace vehicle Design (IPAD). Volume 6: IPAD system development and operation
The strategy of the IPAD implementation plan presented, proposes a three phase development of the IPAD system and technical modules, and the transfer of this capability from the development environment to the aerospace vehicle design environment. The system and technical module capabilities for each phase of development are described. The system and technical module programming languages are recommended as well as the initial host computer system hardware and operating system. The cost of developing the IPAD technology is estimated. A schedule displaying the flowtime required for each development task is given. A PERT chart gives the developmental relationships of each of the tasks and an estimate of the operational cost of the IPAD system is offered
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