Attitude control system for sounding rockets Patent

Development of attitude control system for sounding rocket stabilization during ballistic phase of fligh

In ordained ministry there is neither male nor female? : the personality profile of male and female Anglican clergy engaged in multi-parish rural ministry

Robbins, Francis, and Rutledge (1997) documented the personality profile of Church of England clergymen and clergywomen prior to the ordination of the first women to the priesthood in 1994, drawing on Eysenck's three-dimensional model of personality. They found that the personality profiles of clergymen and clergywomen were indistinguishable. The present paper reports a comparable study conducted in 2004 among 182 clergywomen and 540 clergymen serving in similar parochial posts in order to examine whether the ordination of women to the priesthood had impacted the overall personality profile of Anglican clergy. The data suggest that little change had taken place between the two cohorts of clergy studied. Once again clergywomen and clergymen appeared to be formed in the same image

Fiber optic microphone having a pressure sensing reflective membrane and a voltage source for calibration purpose

A fiber optic microphone is provided for measuring fluctuating pressures. An optical fiber probe having at least one transmitting fiber for transmitting light to a pressure-sensing membrane and at least one receiving fiber for receiving light reflected from a stretched membrane is provided. The pressure-sensing membrane may be stretched for high frequency response. Further, a reflecting surface of the pressure-sensing membrane may have dimensions which substantially correspond to dimensions of a cross section of the optical fiber probe. Further, the fiber optic microphone can be made of materials for use in high temperature environments, for example greater than 1000 F. A fiber optic probe is also provided with a back plate for damping membrane motion. The back plate further provides a means for on-line calibration of the microphone

Geometric analysis of optical frequency conversion and its control in quadratic nonlinear media

We analyze frequency conversion and its control among three light waves using a geometric approach that enables the dynamics of the waves to be visualized on a closed surface in three dimensions. It extends the analysis based on the undepleted-pump linearization and provides a simple way to understand the fully nonlinear dynamics. The Poincaré sphere has been used in the same way to visualize polarization dynamics. A geometric understanding of control strategies that enhance energy transfer among interacting waves is introduced, and the quasi-phase-matching strategy that uses microstructured quadratic materials is illustrated in this setting for both type I and II second-harmonic generation and for parametric three-wave interactions

High temperature fiber optic microphone having a pressure-sensing reflective membrane under tensile stress

A fiber optic microphone is provided for measuring fluctuating pressures. An optical fiber probe having at least one transmitting fiber for transmitting light to a pressure-sensing membrane and at least one receiving fiber for receiving light reflected from a stretched membrane is provided. The pressure-sensing membrane may be stretched for high frequency response. Further, a reflecting surface of the pressure-sensing membrane may have dimensions which substantially correspond to dimensions of a cross section of the optical fiber probe. Further, the fiber optic microphone can be made of materials for use in high temperature environments, for example greater than 1000 F. A fiber optic probe is also provided with a backplate for damping membrane motion. The backplate further provides a means for on-line calibration of the microphone

LENS® and SFF: Enabling Technologies for Optimized Structures

Optimized, lightweight, high-strength structures are needed in many applications from aerospace to automotive. In pursuit of such structures, there have been proposed analytical solutions and some specialized FEA solutions for specific structures such as automobile frames. However, generalized 3D optimization methods have been unavailable for use by most designers. Moreover, in the cases where optimized structural solutions are available, they are often hollow, curving, thin wall structures that cannot be fabricated by conventional manufacturing methods. Researchers at Sandia National Laboratories and the University of Rhode Island teamed to solve these problems. The team has been pursuing two methods of optimizing models for generalized loading conditions, and also has been investigating the methods needed to fabricate these structures using Laser Engineered Net Shaping™ (LENS®) and other rapid prototyping methods. These solid freeform fabrication (SFF) methods offer the unique ability to make hollow, high aspect ratio features out of many materials. The manufacturing development required for LENS to make these complex structures has included the addition of rotational axes to Sandia’s LENS machine bringing the total to 5 controlled axes. The additional axes have required new efforts in process planning. Several of the unique structures that are only now possible through the use of SFF technology are shown as part of the discussion of this exciting new application for SFF.Mechanical Engineerin

Observations of temporal changes of tritium-3He age in the eastern North Atlantic thermocline: Evidence for changes in ventilation

A compilation of fifteen years of tritium and 3He measurements is used to examine the ventilation of the eastern North Atlantic subtropical gyre with specific emphasis on the temporal character of the tracer age field. A multivariate regression analysis in the form of a spatiotemporal Taylor expansion is applied to observations interpolated onto isopycnal surfaces. The time-dependent component of the tracer age field is found to be statistically significant, explaining approximately 10% of the variance of the tracer age observations in the upper thermocline (σ = 26.5) and increasing to roughly 50% of the variance in the lower thermocline (σ = 27.0). The observed transient tracer age increases over the 15 years of observations with the fractional rate of change of the age field varying between 2% and 5% per year. The largest observed changes occur on the deepest, most slowly ventilated isopycnal surfaces. The second derivative of the tritium-3He age with time suggests that the tracer age field may be approaching a steady state. If tritium-3He age is interpreted as a true measure of the advective ventilation age, the temporal changes in age would imply a slackening of the ventilation of the lower main thermocline of greater than 50% from the late 1970\u27s to the early 1990\u27s. However, consideration of the full advective-diffusive balance of tritium-3He age reveals that the changes in tracer age field represent a time-dependent adjustment of the transient tracer concentrations in conjunction with a steady local circulation field. Integral approximations of the upstream evolution of the tracer field also fail to demonstrate evidence for decadal changes in ventilation. The integral balance along the path of subduction yields an improved estimate of the true ventilation age based on the temporal tendency of the age field along the path of ventilation. An approximation of this integral suggests that actual ventilation ages can be up to 40% larger than the measured tracer age in the deeper portions of the North Atlantic thermocline. Proper accounting of the time-dependent biases of the tracer age dating technique are a prerequisite for examining transient tracer measurements for evidence of changes in the physical ventilation of the upper ocean

Experiments in swine feeding. The value of corn and supplementary feeds for pork production.

Corn must necessarily be more freely used than any other concentrated feed for pigs in the Corn Belt, because if properly used it is especially well adapted to pig feeding and can usually be marketed in this way to the very best advantage. But it is generally coming to be recognized that so far as health, thrift and rapidity of gains are concerned, corn alone, at least in dry lot feeding, does not give as satisfactory results, especially for growing pigs, as a combination of corn and some feed adding protein to the ration. Wheat shorts is very commonly considered as the best feed to use with corn for young pigs, but other feeds are. upon the market which contain still larger quantities of protein and their merits for pig feeding deserve investigation. If a small reduction in the cost of feeding each- hog in Iowa can be effected by the judicious uses of these feeds, the aggregate for the state will be enormous. Iowa has 7,947,000 hogs, which, with the exception of Illinois with her 4,684,000, is more than twice as many as any other state and about one-sixth the total number in the United States. During the past season Iowa raised more corn than any other state, the crop being about 388,000,000 bushels. With feeds at the usual prices, it is an easy matter by their judicious selection to so supplement com as to add five to fifteen cents per bushel to the profit from feeding corn, thus effecting a reduction of 50 cents to $1.00 on each 100 lbs. gain in weight by the pigs. In the aggregate, if these modest profits are realized they will amount to millions of dollars to Iowa farmers

Solidification fronts in supercooled liquids: how rapid fronts can lead to disordered glassy solids

We determine the speed of a crystallisation (or more generally, a solidification) front as it advances into the uniform liquid phase after the system has been quenched into the crystalline region of the phase diagram. We calculate the front speed by assuming a dynamical density functional theory model for the system and applying a marginal stability criterion. Our results also apply to phase field crystal (PFC) models of solidification. As the solidification front advances into the unstable liquid phase, the density profile behind the advancing front develops density modulations and the wavelength of these modulations is a dynamically chosen quantity. For shallow quenches, the selected wavelength is precisely that of the crystalline phase and so well-ordered crystalline states are formed. However, when the system is deeply quenched, we find that this wavelength can be quite different from that of the crystal, so that the solidification front naturally generates disorder in the system. Significant rearrangement and ageing must subsequently occur for the system to form the regular well-ordered crystal that corresponds to the free energy minimum. Additional disorder is introduced whenever a front develops from random initial conditions. We illustrate these findings with results obtained from the PFC.Comment: 14 pages, 7 figure

Jamming under tension in polymer crazes

Molecular dynamics simulations are used to study a unique expanded jammed state. Tension transforms many glassy polymers from a dense glass to a network of fibrils and voids called a craze. Entanglements between polymers and interchain friction jam the system after a fixed increase in volume. As in dense jammed systems, the distribution of forces is exponential, but they are tensile rather than compressive. The broad distribution of forces has important implications for fibril breakdown and the ultimate strength of crazes.Comment: 4 pages, 4 figure