Ballpoint probe gives optimum results in ultrasonic testing

Ballpoint-type ultrasonic probe assembly focuses its beam precisely on the bond lines of a composite thin face sheet structure when testing for bond integrity. It can scan in any direction, and eliminate external couplant spray

System for measuring roundness and concentricity of large tanks

Equipment measures the roundness and concentricity of large, massive tanks. The equipment includes a 34-foot rotary table, a variable reluctance displacement transducer, an electronics console, a digital computer, and a 5-foot plotter used for final data display

Solar residential heating and cooling system

System has been placed in operation to verify technical feasibility of using solar energy to provide residential heating and cooling. Complete system analysis was performed to provide design information

Minimum noise impact aircraft trajectories

Numerical optimization is used to compute the optimum flight paths, based upon a parametric form that implicitly includes some of the problem restrictions. The other constraints are formulated as penalties in the cost function. Various aircraft on multiple trajectores (landing and takeoff) can be considered. The modular design employed allows for the substitution of alternate models of the population distribution, aircraft noise, flight paths, and annoyance, or for the addition of other features (e.g., fuel consumption) in the cost function. A reduction in the required amount of searching over local minima was achieved through use of the presence of statistical lateral dispersion in the flight paths

Solar residential heating and cooling system development test program

A solar heating and cooling system is described, which was installed in a simulated home at Marshall Space Flight Center. Performance data are provided for the checkout and initial operational phase for key subsystems and for the total system. Valuable information was obtained with regard to operation of a solar cooling system during the first summer of operation. Areas where improvements and modifications are required to optimize such a system are discussed

Sub-grid scale representation of vegetation in global land surface schemes: implications for estimation of the terrestrial carbon sink

Terrestrial ecosystem models commonly represent vegetation in terms of plant functional types (PFTs) and use their vegetation attributes in calculations of the energy and water balance as well as to investigate the terrestrial carbon cycle. Sub-grid scale variability of PFTs in these models is represented using different approaches with the "composite" and "mosaic" approaches being the two end-members. The impact of these two approaches on the global carbon balance has been investigated with the Canadian Terrestrial Ecosystem Model (CTEM v 1.2) coupled to the Canadian Land Surface Scheme (CLASS v 3.6). In the composite (single-tile) approach, the vegetation attributes of different PFTs present in a grid cell are aggregated and used in calculations to determine the resulting physical environmental conditions (soil moisture, soil temperature, etc.) that are common to all PFTs. In the mosaic (multi-tile) approach, energy and water balance calculations are performed separately for each PFT tile and each tile's physical land surface environmental conditions evolve independently. Pre-industrial equilibrium CLASS-CTEM simulations yield global totals of vegetation biomass, net primary productivity, and soil carbon that compare reasonably well with observation-based estimates and differ by less than 5% between the mosaic and composite configurations. However, on a regional scale the two approaches can differ by > 30%, especially in areas with high heterogeneity in land cover. Simulations over the historical period (1959–2005) show different responses to evolving climate and carbon dioxide concentrations from the two approaches. The cumulative global terrestrial carbon sink estimated over the 1959–2005 period (excluding land use change (LUC) effects) differs by around 5% between the two approaches (96.3 and 101.3 Pg, for the mosaic and composite approaches, respectively) and compares well with the observation-based estimate of 82.2 ± 35 Pg C over the same period. Inclusion of LUC causes the estimates of the terrestrial C sink to differ by 15.2 Pg C (16%) with values of 95.1 and 79.9 Pg C for the mosaic and composite approaches, respectively. Spatial differences in simulated vegetation and soil carbon and the manner in which terrestrial carbon balance evolves in response to LUC, in the two approaches, yields a substantially different estimate of the global land carbon sink. These results demonstrate that the spatial representation of vegetation has an important impact on the model response to changing climate, atmospheric CO₂ concentrations, and land cover

Hedge Funds: Do They Do What They Say They Do?

The purpose of this research is two-fold, to determine if hedge funds follow their stated strategy styles and to examine how hedge funds’ strategy allocations evolve over time in response to changed economic and market conditions.  Our key advance is that we show that standard linear style models like that of Sharpe (1992) can be applied to hedge fund returns as long as the returns of the style indices in the model themselves display the nonlinear option-like characteristics of hedge fund returns.  For our research, the returns of our sample of Funds of Hedge Funds are strongly correlated to the returns of portfolios of hedge fund investment style indices.  In this way, we capture the spirit of Fung & Hsieh's (2002) Asset-Based Style Factors for Hedge Funds.  Based on our results, it appears that the answer to the first question is “somewhat”, while we find ample evidence of significant shifts in allocation among the Fund of Hedge Funds from the first sample period (1997-2001) to the second (2002-2006).  The changes in allocation appear to rationally reflect the changed economic conditions and investment opportunities existing at the time

Learning To Invest A New Frontier

The purpose of this paper is to introduce a new and innovative course in the field of Finance, promoting the notion of “hands-on” instruction through the management of real-dollars.  This course solely focuses on the management of such a Student Managed Fund (SMF).  Employing a seminar setting on the undergraduate level, while using the latest security analysis technology, students take part in every aspect of fund management.  From the initial stages of forming an investment strategy, to the later stages of portfolio reallocation, students are grounded in reality.  This paper will illustrate the objectives set forth by the professor(s) and the methods used by the students to accomplish said goals.  The focus will be on the differences in risk preferences and actions due to the management of real money versus simulated “play money,” as well as the benefits garnered from such a course.  In conjunction with the introduction of this new course, this research will formulate the methodology behind the use of a real-time financial analysis platform, such as SDS MarketWatch, to create and manage a portfolio.  Lastly, the benefits of using such a real-time financial analysis platform will be made evident