Active rc filter permits easy trade-off of amplifier gain and sensitivity to gain

Passive RC network was designed with zeros of transmission in the right half of the complex frequency plane in the feedback loop of a simple negative-gain amplifier. The proper positioning provides any desired trade-off between amplifier gain and sensitivity to amplifier gain

An Analysis of Consumption and Expenditures for Lithuanian Households Using Budget Survey Data

Recent household budget survey data for Lithuania provide a profile of expenditure patterns for households by income level and living in either urban or rural areas. This paper provides an overview of expenditures and gives estimates of Engel functions and income elasticities for major expenditure groups and for food commodities. Food commodities are relatively important to households in both urban and rural areas and show relatively inelastic response to income levels. Based in an assumed reduction in income for 1991 of 41 percent, food shares are projected to increase by nearly 36 percent from 1989 levels. This is likely to be a lower bound for the anticipated changes

Fabrication of a Self-Assembled and Flexible SERS Nanosensor for Explosive Detection at Parts-Per-Quadrillion Levels from Fingerprints

Apart from high sensitivity and selectivity of surface-enhanced Raman scattering (SERS)-based trace explosive detection, efficient sampling of explosive residue from real world surfaces is very important for homeland security applications. Herein, we demonstrate an entirely new SERS nanosensor fabrication approach. The SERS nanosensor was prepared by self-assembling chemically synthesized gold triangular nanoprisms (Au TNPs), which we show display strong electromagnetic field enhancements at the sharp tips and edges, onto a pressure-sensitive flexible adhesive film. Our SERS nanosensor provides excellent SERS activity (enhancement factor = ∼6.0 × 106) and limit of detection (as low as 56 parts-per-quadrillions) with high selectivity by chemometric analyses among three commonly military high explosives (TNT, RDX, and PETN). Furthermore, the SERS nanosensors present excellent reproducibility (<4.0% relative standard deviation at 1.0 μM concentration) and unprecedentedly high stability with a “shelf life” of at least 5 months. Finally, TNT and PETN were analyzed and quantified by transferring solid explosive residues from fingerprints left on solid surfaces to the SERS nanosensor. Taken together, the demonstrated sensitivity, selectivity, and reliability of the measurements as well as with the excellent shelf life of our SERS nanosensors obviate the need for complicated sample processing steps required for other analytical techniques, and thus these nanosensors have tremendous potential not only in the field of measurement science but also for homeland security applications to combat acts of terror and military threats

Analysis of the Worst Case Space Complexity of a PR Quadtree

We demonstrate that a resolution-r PR quadtree containing n points has, in the worst case, at most nodes. This captures the fact that as n tends towards 4r, the number of nodes in a PR quadtree quickly approaches O(n). This is a more precise estimation of the worst case space requirement of a PR quadtree than has been attempted before

Seismic Analysis of Spinney Mountain Dam

The Spinney Mountain Dam, now under construction in central Colorado, is a zoned earth embankment with a maximum height of 95 feet above foundation. Detailed geological investigations revealed rejuvenated sediments of nearby older faults, which have undergone tectonic movement within the past 13,000 to 30,000 years and hence are considered capable. Studies indicate the largest earthquake expected on the controlling fault would have a Richter Magnitude of about 6.2, implying peak ground accelerations at the site of about 0.6g and a 15-second duration of strong motion. Displacement on a branch of the main capable fault during such an event is estimated at four to six inches. Slope deformation analyses estimate a movement at the crest of the dam of not more than two inches horizontally and considerably less vertically, which would not result in a significant decrease in strength of the compacted soils. Reservoir induced seismicity is not considered to be a hazard

Tunable bandpass filter with variable selectivity

Basic active RC networks constructed from stages that realize second-order transfer functions using two integrators offer excellent stability. Modifications of the basic network produce a highly stable bandpass filter having separate controls that independently adjust center frequency, Q, and center frequency gain

Policy and Forecasting Models for the Chinese, South Korean, Australian, and European Union Meat Sectors

Recent strong growth in the export of U.S. meat products combined with increasing Asian demand for feed grains has focused attention on tools to analyze growth potential in these markets. This paper demonstrates that structural models of the livestock industries in foreign countries can provide information about the prospects for meat and related agricultural commodities. They can also be used to analyze the impact of policy changes

Speed and Surface Speed and Magnitude of Knee Adduction

Frontal plane knee biomechanics, in particular speed and magnitude of knee adduction motion, are implicated in knee osteoarthritis development. Although individuals are between 50% to 90% more likely to develop knee osteoarthritis after anterior cruciate ligament reconstruction (ACL-R), it is unknown if ACL-R individuals exhibit knee adduction biomechanics related to OA development. This study sought to quantify speed and magnitude of knee adduction for knee OA and ACL-R individuals. We hypothesize that OA will exhibit larger, faster knee adduction biomechanics than ACL-R, which will increase at great walk speed and over a challenging surface. Six individuals with ACL-R and 8 individuals with knee OA had knee adduction quantified as they walked 1.3 m/s and at a self-selected speed over a flat and an uneven surface. Peak of stance, and average and maximum velocity of knee adduction joint angle and moment between heel strike and peak of stance were submitted to repeated measures ANOVA to compare main and interaction effects between group, speed and surface. There was a walk speed by group interaction for peak knee adduction moment (p = 0.048). Walk speed impacted maximum knee adduction joint angle (p=0.004) and moment velocity (p=0.041), while surface impacted peak knee adduction joint angle (p=0.035) and maximum knee adduction joint moment velocity (p=0.007). In partial agreement with our hypothesis, speed and magnitude knee adduction biomechanics increased with walk speed and surface, but OA did not consistently exhibit larger knee adduction biomechanics than ACL-R

Rydberg trimers and excited dimers bound by internal quantum reflection

Quantum reflection is a pure wave phenomena that predicts reflection of a particle at a changing potential for cases where complete transmission occurs classically. For a chemical bond, we find that this effect can lead to non-classical vibrational turning points and bound states at extremely large interatomic distances. Only recently has the existence of such ultralong-range Rydberg molecules been demonstrated experimentally. Here, we identify a broad range of molecular lines, most of which are shown to originate from two different novel sources: a single-photon associated triatomic molecule formed by a Rydberg atom and two ground state atoms and a series of excited dimer states that are bound by a so far unexplored mechanism based on internal quantum reflection at a steep potential drop. The properties of the Rydberg molecules identified in this work qualify them as prototypes for a new type of chemistry at ultracold temperatures.Comment: 6 pages, 3 figures, 1 tabl