Design, development, and fabrication of a prototype ice pack heat sink subsystem. Flight experiment physical phenomena experiment chest

The concept of a flight experiment physical phenomena experiment chest, to be used eventually for investigating and demonstrating ice pack heat sink subsystem physical phenomena during a zero gravity flight experiment, is described

Physical Acoustics

Contains research objectives and reports on three research projects.U.S. Navy (Office of Naval Research) under Contract Nonr-1841(42

Physical Acoustics

Contains reports on seven research projects.Office of Naval Research (Contract Nonr-1841(42

Practical solution to the Monte Carlo sign problem: Realistic calculations of 54Fe

We present a practical solution to the "sign problem" in the auxiliary field Monte Carlo approach to the nuclear shell model. The method is based on extrapolation from a continuous family of problem-free Hamiltonians. To demonstrate the resultant ability to treat large shell-model problems, we present results for 54Fe in the full fp-shell basis using the Brown-Richter interaction. We find the Gamow-Teller beta^+ strength to be quenched by 58% relative to the single-particle estimate, in better agreement with experiment than previous estimates based on truncated bases.Comment: 11 pages + 2 figures (not included

Comparison of Lidar Backscatter with Particle Distribution and GOES-7 Data in Hurricane Juliette

Measurements of calibrated backscatter, using two continuous wave Doppler lidars operating at wavelengths 9.1 and 10.6 micrometers were obtained along with cloud particle size distributions in Hurricane Juliette on 21 September 1995 at altitude approximately 11.7 km. Agreement between backscatter from the two lidars and with the cloud particle size distribution is excellent. Features in backscatter and particle number density compare well with concurrent GOES-7 infrared images

Co-occurring disorders in children who stutter

Abstract This study used a mail survey to determine the (a) percentage of children who stutter with co-occurring non-speech disorders, speech disorders, and language disorders, and (b) frequency, length of sessions, and type of treatment services provided for children who stutter with co-occurring disorders. Respondents from a nationwide sample included 1184 speech-language pathologists (SLPs). Of the 2628 children who stuttered, 62.8% had other cooccurring speech disorders, language disorders, or non-speech-language disorders. Articulation disorders (33.5%) and phonology disorders (12.7%) were the most frequently reported cooccurring speech disorders. Only 34.3% of the children who stuttered had co-occurring nonspeech-language disorders. Of those children with co-occurring non-speech-language disorders, learning disabilities (15.2%), literacy disorders (8.2%), and attention deficit disorders (ADD) (5.9%) were the most frequently reported. Chi-square analyses revealed that males were more likely to exhibit co-occurring speech disorders than females, especially articulation and phonology. Co-occurring non-speech-language disorderswere also significantly higher in males than females. Treatment decisions by SLPs are also discussed. Learning outcomes: As a result of this activity, the participant should: (1) have a better understanding of the co-occurring speech disorders, language disorders, and non-speech disorders in children who stutter; (2) identify the speech disorders, language disorders, and non-speech disorders with the highest frequency of occurrence in children who stutter; and (3) be aware of the subgroups of children with co-occurring disorders and their potential impact on assessment and treatment.

Proceedings of the Tenth Annual Beef Cattle Short Course.

91 p

Electron quantum metamaterials in van der Waals heterostructures

In recent decades, scientists have developed the means to engineer synthetic periodic arrays with feature sizes below the wavelength of light. When such features are appropriately structured, electromagnetic radiation can be manipulated in unusual ways, resulting in optical metamaterials whose function is directly controlled through nanoscale structure. Nature, too, has adopted such techniques -- for example in the unique coloring of butterfly wings -- to manipulate photons as they propagate through nanoscale periodic assemblies. In this Perspective, we highlight the intriguing potential of designer sub-electron wavelength (as well as wavelength-scale) structuring of electronic matter, which affords a new range of synthetic quantum metamaterials with unconventional responses. Driven by experimental developments in stacking atomically layered heterostructures -- e.g., mechanical pick-up/transfer assembly -- atomic scale registrations and structures can be readily tuned over distances smaller than characteristic electronic length-scales (such as electron wavelength, screening length, and electron mean free path). Yet electronic metamaterials promise far richer categories of behavior than those found in conventional optical metamaterial technologies. This is because unlike photons that scarcely interact with each other, electrons in subwavelength structured metamaterials are charged, and strongly interact. As a result, an enormous variety of emergent phenomena can be expected, and radically new classes of interacting quantum metamaterials designed

Comparisons of Supergranule Characteristics During the Solar Minima of Cycles 22/23 and 23/24

Supergranulation is a component of solar convection that manifests itself on the photosphere as a cellular network of around 35 Mm across, with a turnover lifetime of 1-2 days. It is strongly linked to the structure of the magnetic field. The horizontal, divergent flows within supergranule cells carry local field lines to the cell boundaries, while the rotational properties of supergranule upflows may contribute to the restoration of the poloidal field as part of the dynamo mechanism that controls the solar cycle. The solar minimum at the transition from cycle 23 to 24 was notable for its low level of activity and its extended length. It is of interest to study whether the convective phenomena that influences the solar magnetic field during this time differed in character to periods of previous minima. This study investigates three characteristics (velocity components, sizes and lifetimes) of solar supergranulation. Comparisons of these characteristics are made between the minima of cycles 22/23 and 23/24 using MDI Doppler data from 1996 and 2008, respectively. It is found that whereas the lifetimes are equal during both epochs (around 18 h), the sizes are larger in 1996 (35.9 +/- 0.3 Mm) than in 2008 (35.0 +/- 0.3 Mm), while the dominant horizontal velocity flows are weaker (139 +/- 1 m/s in 1996; 141 +/- 1 m/s in 2008). Although numerical differences are seen, they are not conclusive proof of the most recent minimum being inherently unusual.Comment: 22 pages, 5 figures. Solar Physics, in pres