Kinematic analysis of conically scanned environmental properties

A method for determining the velocity of features such as wind. The method preferably includes producing sensor signals and projecting the sensor signals sequentially along lines lying on the surface of a cone. The sensor signals may be in the form of lidar, radar or sonar for example. As the sensor signals are transmitted, the signals contact objects and are backscattered. The backscattered sensor signals are received to determine the location of objects as they pass through the transmission path. The speed and direction the object is moving may be calculated using the backscattered data. The data may be plotted in a two dimensional array with a scan angle on one axis and a scan time on the other axis. The prominent curves that appear in the plot may be analyzed to determine the speed and direction the object is traveling

Assessing Probabilistic Methods for Liquefaction Potential Evaluation — An Update

This paper presents an assessment of existing probabilistic methods for liquefaction potential evaluation. Emphasis is placed on comparison of probabilities of liquefaction calculated with four different methods. Two of these methods are based on SPT, and the other two are based on CPT. In both SPT- and CPT-based evaluations, logistic regression and Bayesian techniques are applied to map factor of safety to probability of liquefaction. The present study shows that the Bayesian approach yields more conservative results than does the logistic regression approach, although results from the two approaches are quite comparable. Discussion of the procedure for risk-based liquefaction potential evaluation is also presented

Probability-Based Liquefaction Evaluation Using Shear Wave Velocity Measurements

Three preliminary probability-based models and one artificial neural network model for evaluating soil liquefaction potential using shear wave velocity measurements are presented and compared with the deterministic curves developed by Andrus et al. The probability models are developed using logistic regression and Bayesian techniques applied to the same case history data used to develop the deterministic curves. The case history data consists of in situ shear wave velocity measurements at over 70 sites and field performance data from 26 earthquakes. The artificial neural network model is a high-order function capable of tracking the irregular boundary separating individual liquefaction and no liquefaction case histories. From the logistic regression and Bayesian models, the deterministic curve is characterized with a probability of about 30 %. This finding indicates that the shear wave-based deterministic curve and the SPT-based deterministic curve exhibit similar conservatism. The results provide a method for liquefaction risk analysis

The Impact of an International Interprofessional Experience on Perceptions of Pharmacist-Physician Relationships

Objective. To assess the impact of this international interprofessional learning experience on perceptions of pharmacist-physician relationships and interprofessional teams. Methods. Medical and pharmacy students completed a one-week interprofessional medical mission experience in the Dominican Republic. Anonymous surveys were administered to 17 students before and after completion to measure perceptions of pharmacist-physician relationships and interprofessional teams. Responses were matched and changes in perceptions were analyzed using the Wilcoxon Signed Rank test. The SPICE-R2 instrument was administered after the experience to measure attitudes toward interprofessional teams. Results. Of the 17 participants, 100% responded to all surveys. Significant improvements were seen in the perception of pharmacists as an integral part of medical mission trips (P=0.035) and confidence in the ability to communicate with other healthcare disciplines (P=0.033). All students stated they would recommend this experience, and agreed that interprofessional experiences enhance their team work skills and should be incorporated into their education. Student comments supported that this was a meaningful and effective interprofessional experience. The results of the SPICE-R2 demonstrated positive attitudes about interprofessional teams, with all questions having a median score of “agree” or “strongly agree.” Conclusions. An international interprofessional experience improved the perception of pharmacist-physician relationships. The experience provided understanding of the other healthcare discipline, an appreciation for the importance of interprofessional teamwork, increased student confidence in communicating with the other discipline, and cultivated interest in future interprofessional collaboration

Complex switching dynamics of interacting light in a ring resonator

Microresonators are micron-scale optical systems that confine light using total internal reflection. These optical systems have gained interest in the last two decades due to their compact sizes, unprecedented measurement capabilities, and widespread applications. The increasingly high finesse (or $Q$ factor) of such resonators means that nonlinear effects are unavoidable even for low power, making them attractive for nonlinear applications, including optical comb generation and second harmonic generation. In addition, light in these nonlinear resonators may exhibit chaotic behavior across wide parameter regions. Hence, it is necessary to understand how, where, and what types of such chaotic dynamics occur before they can be used in practical devices. We consider a pair of coupled differential equations that describes the interactions of two optical beams in a single-mode resonator with symmetric pumping. Recently, it was shown that this system exhibits a wide range of fascinating behaviors, including bistability, symmetry breaking, chaos, and self-switching oscillations. We employ here a dynamical system approach to identify, delimit, and explain the regions where such different behaviors can be observed. Specifically, we find that different kinds of self-switching oscillations are created via the collision of a pair of asymmetric periodic orbits or chaotic attractors at Shilnikov homoclinic bifurcations, which acts as a gluing bifurcation. We present a bifurcation diagram that shows how these global bifurcations are organized by a Belyakov transition point (where the stability of the homoclinic orbit changes). In this way, we map out distinct transitions to different chaotic switching behavior that should be expected from this optical device.Comment: 22 pages, 10 figure

15N Values in Crassostrea virginica Shells Provides Early Direct Evidence for Nitrogen Loading to Chesapeake Bay

Crassostrea virginica is one of the most common estuarine bivalves in the United States? east coast and is frequently found in archaeological sites and sub-fossil deposits. Although there have been several sclerochronological studies on stable carbon and oxygen isotopes in the shells of this species, less is known about ?15N values within their shells, which could be a useful paleoenvironmental proxy to assess estuarine nitrogen dynamics. Modern C. virginica samples were collected in Chesapeake Bay for comparison with archaeological shells from nearby sites ranging in age from ~100 to 3,200 years old. Left valves were sampled by milling the hinge area and the resulting powder was analyzed for %N and ?15N values. Comparison of ?15N values between C. virginica shells shows relatively constant values from ~1250 BC to ~1800 AD. After ~1800 AD, there are rapid increases in 15N enrichment in the shells, which continue to increase in value up to the modern shell values. The increase in ?15N values is evidence of early anthropogenic impact in Chesapeake Bay. These results corroborate the observation that coastal nitrogen pollution occurred earlier than the 19th century and support the use of oyster shell ?15N values as a useful environmental proxy