Vibration Responses of Test Structure No. 2 During the Edward Air Force Base Phase of the National Sonic Boom Program

In order to evaluate reaction of people to sonic booms of varying overpressures and time durations, a series of closely controlled and systematic flight tests/studies were conducted from June 3 to June 23, 1966. The dynamic responses of several building structures were measured, with emphasis on a two-story residence structure. Sample acceleration and strain recordings from F-104, B-58, and XB-70 sonic boom exposures are included, along with tabulations of the maximum acceleration and strain values measured for each one of about 140 flight tests. These data are compared with similar measurements for engine noise exposures of the building during simulated landing approaches and takeoffs of KC-135 aircraft

Vibration responses of test structure no. 1 during the Edwards Air Force Base phase of the national sonic boom program

In order to evaluate reaction of people to sonic booms of varying overpressures and time durations, a series of closely controlled and systematic flight test studies were conducted in the vicinity of Edwards AFB, California, from June 3 to June 23, 1966. The dynamic responses of several building structures were measured as a part of these studies, and the measurements made in a one-story residence structure (Edwards test structure No. 1) are presented. Sample acceleration and strain recordings are presented from F-104, B-58, and XB-70 sonic-boom exposures, along with tabulations of the maximum acceleration and strain values measured for each one of about 140 flight tests. These data are compared with similar measurements for engine noise exposures of the building during simulated landing approaches and takeoffs of KC-135 aircraft

Factors associated with survival of horses following relaparotomy

Relaparotomy may be required to investigate and manage complications that occur following surgical management of colic.To report factors associated with survival following relaparotomy.Retrospective cohort study.Records of horses that had undergone exploratory laparotomy for treatment of colic over a 10-year period (2002 - 2012) and had undergone relaparotomy <8 weeks following the initial surgery were reviewed. Descriptive data were generated and association with survival time was modelled using Cox proportional hazards models.Relaparotomy was performed in 96 horses at <8 weeks following initial surgery at a median of 4 days. This represented 6.3% of horses that underwent laparotomy during the study period (n = 1,531). Relaparotomy was most frequently undertaken based on signs of persistent postoperative colic (76%; n = 73). Short-term survival for horses undergoing relaparotomy due to persistent colic was 53%, incisional dehiscence 50% postoperative reflux 37%, haemoperitoneum 17% and septic peritonitis 0%. Median survival was 6 days for all horses undergoing relaparotomy and 778 days for those that recovered following anaesthesia. Non-survival was associated with increased packed cell volume at 24 h following initial laparotomy (HR 1.06, 95% CI 1.04-1.10, P = 0.009), peritonitis as a reason for undertaking relaparotomy (HR 4.41, 95% CI 1.43-13.6, P = 0.01) and adhesions found at relaparotomy (HR 1.77, 95% CI 1.03-3.04, P = 0.04). Increased likelihood of survival was associated with colic signs being the reason for performing relaparotomy (HR 0.48, 95% CI 0.26-0.88, P = 0.02) and small intestinal distension found at relaparotomy (HR 0.53, 95% CI 0.29-0.96, P = 0.04).This study has provided information about survival rates and risk factors for survival in horses undergoing relaparotomy that can assist clinicians and owners when determining whether to perform relaparotomy and in predicting the likely surgical outcome. This article is protected by copyright. All rights reserved

Direct measurement of molecular stiffness and damping in confined water layers

We present {\em direct} and {\em linear} measurements of the normal stiffness and damping of a confined, few molecule thick water layer. The measurements were obtained by use of a small amplitude (0.36 $\textrm{\AA}$), off-resonance Atomic Force Microscopy (AFM) technique. We measured stiffness and damping oscillations revealing up to 7 layers separated by 2.56 $\pm$ 0.20 $\textrm{\AA}$. Relaxation times could also be calculated and were found to indicate a significant slow-down of the dynamics of the system as the confining separation was reduced. We found that the dynamics of the system is determined not only by the interfacial pressure, but more significantly by solvation effects which depend on the exact separation of tip and surface. Thus ` solidification\rq seems to not be merely a result of pressure and confinement, but depends strongly on how commensurate the confining cavity is with the molecule size. We were able to model the results by starting from the simple assumption that the relaxation time depends linearly on the film stiffness.Comment: 7 pages, 6 figures, will be submitted to PR

A Decision Analysis Perspective on Multiple Response Robust Optimization

Decisions in which multiple objectives must be optimized simultaneously occur frequently in government, military, and industrial settings. One method a decision maker may use to assist in such decisions is the application of a desirability function. An informed specification of the desirability function\u27s parameters is essential to accurately describe the decision maker\u27s value trade-offs and risk preference. This thesis uses utility transversality to analyze the implicit trade-off and risk attitude assumptions attendant to the desirability function. The desirability function does not explicitly account for response variability. A robust solution takes not only the expected response into account, but also its variance. Assessing a utility function over desirability as a means to describe the decision maker\u27s risk attitude produces a robust operating solution consistent with those preferences. This thesis examines robustness as it applies to the desirability function in a manufacturing experiment example. Different levels of diplomatic, informational, military, and economic (DIME) instruments of national policy are investigated to examine their effect on the political, military, economic, social, infrastructure, and information (PMESII) systems of a nation. AFRL\u27s National Operational Environment Model (NOEM) serves as a basis for identifying a robust national policy in a scenario involving the Democratic Republic of Congo

Seasonal Adjustment Methods and the Determination of Turning Points of the EMU Business Cycle

In this paper, we investigate the impact of the adjustment for seasonal effects with different seasonal adjustment methods, the possible pre-treatment for calendar effects and the different order of aggregation and adjustment for the determination of the turning points of the European business cycle. The European business cycle is represented first by the GDP series (referring to the classical definition of a business cycle as fluctuations in the level of economic activity), and then by deviations from trend (which corresponds to the definition of the cycle as changing capacity utilisation). The turning points are determined using a mechanical procedure (Bry/Boschan methodology), which ensure that all series are treated alike. The comparison of turning points in the classical and growth cycles has brought the following results: 1.The order of seasonal adjustment and aggregation has only minor effects on the determined turning points of the European business cycle. 2.If the series are pretreated for calendar effects, turning points in the aggregated series can differ significantly. 3.It is not relevant whether the series were adjusted with a single method or with different methods (mixed aggregates)

Comparison of measured and calculated aircraft lift generated pressures

Lift generated pressures produced by large, heavy aircraft at low altitudes were investigated due to concern over their possible effects on ground objects. Aircraft lift generated pressures were calculated using elementary airfoil theory, and these values were compared with ground level measurements made during an overflight program. The predicted and the measured values were in relatively good agreement. Due to lack of experimental investigations of this phenomenon, opportunity was taken during an overflight program to use a specially instrumented test range to measure the ground pressures produced for a range of aircraft weights and distances

Search for Gravitational Waves from Primordial Black Hole Binary Coalescences in the Galactic Halo

We use data from the second science run of the LIGO gravitational-wave detectors to search for the gravitational waves from primordial black hole (PBH) binary coalescence with component masses in the range 0.2--$1.0 M_\odot$. The analysis requires a signal to be found in the data from both LIGO observatories, according to a set of coincidence criteria. No inspiral signals were found. Assuming a spherical halo with core radius 5 kpc extending to 50 kpc containing non-spinning black holes with masses in the range 0.2--$1.0 M_\odot$, we place an observational upper limit on the rate of PBH coalescence of 63 per year per Milky Way halo (MWH) with 90% confidence.Comment: 7 pages, 4 figures, to be submitted to Phys. Rev.