2,061 research outputs found
An exploratory aerodynamic and structural investigation of all-flexible parawings
Aerodynamic and structural aspects of all-flexible parawing
A New Look at the Axial Anomaly in Lattice QED with Wilson Fermions
By carrying out a systematic expansion of Feynman integrals in the lattice
spacing, we show that the axial anomaly in the U(1) lattice gauge theory with
Wilson fermions, as determined in one-loop order from an irrelevant lattice
operator in the Ward identity, must necessarily be identical to that computed
from the dimensionally regulated continuum Feynman integrals for the triangle
diagrams.Comment: 1 figure, LaTeX, 18 page
Effects of Baffles on the Performance of Anerobic Waste Stabilization Ponds
The performance of three baffled model ponds was monitored and compared to the performance of an unbaffled model pond utilizing four hydraulic and organic loading rates. All four ponds were operated simultaneously under the same environmental conditions using a synthetic wastewater. Removal of organic carbon by the biological system in the different pond configurations only varied from 94-98 percent at the longest detention time (15 days); however, a considerable effect of the baffling was observed at the lower detention times. At a hydraulic detention time of 1.5 days the percent carbon removal was 53, 60, 62, and 70 percent for the control, end-around, over-and-under, and longitudinal baffling systems, respectively. The biological kinetics of the model ponds were determined using three mathematical models. Performance was evaluated by using the kinetic parameters and conventional stabilization pond operating parameters. Direct comparisons with the performance parameters of the model ponds appear valid for analysis of the three models studied. The performance of the baffled ponds was described by a completely mixed model incorporating attached biomass; however, the performance of the unbaffled control pond was not described by the completely mixed model. Performance parameters of the baffled, model ponds were significantly better than the control pond
A Survey of Administrative Practices and Policies Among NCAA Division III Football Programs
The purpose of this study was to examine and describe selected administrative practices and policies in the areas of staffing, recruiting, and budgeting for NCAA Division III football programs. Subproblems inherent in this study were (a) to compare these practices and policies according to the institutions size and (b) to compare these practices and policies according to the football program\u27s winning percentage over the last 5 years.
A questionnaire was sent to all 202 programs who participated in NCAA Division III football during the 1985 season. One hundred fifteen institutions completed and returned the questionnaire. The questionnaire obtained specific information regarding program staffing, recruiting, and budgeting.
The study showed that there was a tremendous variability among NCAA Division III football programs and their practices and policies regarding staffing, recruiting, and budgeting. Some of the greatest differences were found in the number of assistant coaches and their percentage workload in football.
In examining these administrative practices and policies according to size of institution and winning percentage some trends were identified. Winning programs showed a higher mean number of full-time assistant coaches, a higher mean percentage workload in football, and more recruiting responsibility among their assistant coaches. Institutions with enrollments of over 3,000 students also tended to lead in these same areas within the institutional size groupings.
These same two groupings, winning programs and those schools of over 3,000 students also tended to have larger football operating budgets
Anonymous shell companies: A global audit study and field experiment in 176 countries
To test whether firms behave consistently with international law prohibiting anonymous incorporation, we conducted a global audit study and field experiment, using data from 1639 incorporation firms in 176 countries. We requested anonymous incorporation and randomly assigned references to international law, threat of penalties, norms of appropriate behavior, or a placebo. We find a substantial number of firms willing to flout international standards and show that those in OECD countries proved significantly less compliant with rules than in developing countries or tax havens. Firms in tax havens displayed significantly greater compliance and were sensitive to experimental interventions invoking international law
Binary Cosmic Strings
The properties of cosmic strings have been investigated in detail for their
implications in early-universe cosmology. Although many variations of the basic
structure have been discovered, with implications for both the microscopic and
macroscopic properties of cosmic strings, the cylindrical symmetry of the
short-distance structure of the string is generally unaffected. In this paper
we describe some mechanisms leading to an asymmetric structure of the string
core, giving the defects a quasi-two-dimensional character. We also begin to
investigate the consequences of this internal structure for the microscopic and
macroscopic physics.Comment: 19 pages; uses harvmac (not included
Age of the Peach Springs Tuff, Southeastern California and Western Arizona
Sanidine separates from pumice of the early Miocene Peach Springs Tuff are concordantly dated at 18.5 ± 0.2 Ma by two isotopic techniques. The Peach Springs Tuff is the only known unit that can be correlated between isolated outcrops of Miocene strata from the central Mojave Desert of southeastern California to the western Colorado Plateau in Arizona, across five structural provinces, a distance of 350 km. Thus the age of the Peach Springs Tuff is important to structural and paleogeographic reconstructions of a large region. Biotite and sanidine separates from bulk samples of the Peach Springs Tuff from zones of welding and vapor-phase alteration have not produced consistent ages by the K-Ar method. Published ages of mineral separates from 17 localities ranged from 16.2 to 20.5 Ma. Discordant 40Ar/39Ar incremental release spectra were obtained for one biotite and two of the sanidine separates. Ages that correspond to the last gas increments are as old as 27 Ma. The 40Ar/39Ar incremental release determinations on sanidine separated from blocks of Peach Springs Tuff pumice yield ages of 18.3 ± 0.3 and 18.6 ± 0.4 Ma. Laser fusion measurements yield a mean age of 18.51 ± 0.10. The results suggest that sanidine and biotite K-Ar ages older than about 18.5 Ma are due to inherited Ar from pre-Tertiary contaminants, which likely were incorporated into the tuff during deposition. Sanidine K-Ar ages younger than 18 Ma probably indicate incomplete extraction of radiogenic 40Ar, whereas laser fusion dates of biotite and hornblende younger than 18 Ma likely are due to postdepositional alteration. Laser fusion ages as high as 19.01 Ma on biotite grains from pumice suggest that minerals from pre-Tertiary country rocks also were incorporated in the magma chamber
Liveness-Driven Random Program Generation
Randomly generated programs are popular for testing compilers and program
analysis tools, with hundreds of bugs in real-world C compilers found by random
testing. However, existing random program generators may generate large amounts
of dead code (computations whose result is never used). This leaves relatively
little code to exercise a target compiler's more complex optimizations.
To address this shortcoming, we introduce liveness-driven random program
generation. In this approach the random program is constructed bottom-up,
guided by a simultaneous structural data-flow analysis to ensure that the
generator never generates dead code.
The algorithm is implemented as a plugin for the Frama-C framework. We
evaluate it in comparison to Csmith, the standard random C program generator.
Our tool generates programs that compile to more machine code with a more
complex instruction mix.Comment: Pre-proceedings paper presented at the 27th International Symposium
on Logic-Based Program Synthesis and Transformation (LOPSTR 2017), Namur,
Belgium, 10-12 October 2017 (arXiv:1708.07854
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