Parametric studies of advanced turboprops

The effects of geometric variables (sweep and twist) on the structural performance of advanced turboprops are investigated. The investigation is limited to aerodynamically efficient turboprops using an acceptable design configuration as a baseline. The baseline configuration is modified using a seven by seven array of independently varying sweep and twist parameters while maintaining acceptable aerodynamic efficiency. The turboprop structural performance is evaluated in terms of critical speeds, tip displacements, and vibration frequencies where geometric nonlinearities are included. The results obtained are presented in such a manner as to highlight the effects of sweep and twist on the structural performance of aerodynamically efficient turboprop configurations

Currently Existing Mosquito Control Programs in Minnesota

Mosquito Control in Minnesota is governed by three statutes: Local Pest Control 18.021 -18.022, Mosquito Abatement 18.041 -18.161, and Mosquito Control 473.701 -473.717. Of these only two are actively utilized, 18.021 -18.022 in outstate Minnesota and 473.701 -473.717 in the seven county metropolitan area. Local Pest Control Statute 18.021 -18.022 governs the control of many pests including mosquitoes. The statute is enforced by the Municipal Pest Control Section of the Division of Plant Industry in the Minnesota Department of Agriculture. Pesticides are generally applied to kill adult mosquitoes upon citizen demand

Leak Detection In Large Storage Tanks Using Seismic Boundary Waves

This paper describes a field evaluation of a technique for detecting leaks in large above ground storage tanks. The technique detects leaking tank products in the foundation material by sensing anomalies in seismic boundary waves transmitted across the tank bottom. The evaluation consisted of three steps: (1) investigation of surface (Rayleigh) wave anomalies due to surface soil saturation in linear arrays; (2) evaluation of boundary waves propagated across the bottom of typical tanks; and (3) a surface (Rayleigh) wave experiment using tomography to locate velocity changes due to surface soil saturation. The results of these tests have shown that boundary waves can be easily propagated along a tank bottom and received by conventional geophones, and that soil saturation anomalies can be detected and located using boundary waves and tomographic reconstruction

A versatile source of polarization-entangled photons

We propose a method for the generation of a large variety of entangled states, encoded in the polarization degrees of freedom of N photons, within the same experimental setup. Starting with uncorrelated photons, emitted from N arbitrary single photon sources, and using linear optical tools only, we demonstrate the creation of all symmetric states, e.g., GHZ- and W-states, as well as all symmetric and non-symmetric total angular momentum eigenstates of the N qubit compound.Comment: 4 pages, 3 figure

Generation of Total Angular Momentum Eigenstates in Remote Qubits

We propose a scheme enabling the universal coupling of angular momentum of $N$ remote noninteracting qubits using linear optical tools only. Our system consists of $N$ single-photon emitters in a $\Lambda$-configuration that are entangled among their long-lived ground-state qubits through suitably designed measurements of the emitted photons. In this manner, we present an experimentally feasible algorithm that is able to generate any of the $2^N$ symmetric and nonsymmetric total angular momentum eigenstates spanning the Hilbert space of the $N$-qubit compound.Comment: 5 pages, 4 figures, improved presentation. Accepted in Physical Review

Takagi-Taupin Description of X-ray Dynamical Diffraction from Diffractive Optics with Large Numerical Aperture

We present a formalism of x-ray dynamical diffraction from volume diffractive optics with large numerical aperture and high aspect ratio, in an analogy to the Takagi-Taupin equations for strained single crystals. We derive a set of basic equations for dynamical diffraction from volume diffractive optics, which enable us to study the focusing property of these optics with various grating profiles. We study volume diffractive optics that satisfy the Bragg condition to various degrees, namely flat, tilted and wedged geometries, and derive the curved geometries required for ultimate focusing. We show that the curved geometries satisfy the Bragg condition everywhere and phase requirement for point focusing, and effectively focus hard x-rays to a scale close to the wavelength.Comment: 18 pages, 12 figure

Mid-Infrared Optical Frequency Combs based on Difference Frequency Generation for Molecular Spectroscopy

Mid-infrared femtosecond optical frequency combs were produced by difference frequency generation of the spectral components of a near-infrared comb in a 3-mm-long MgO:PPLN crystal. We observe strong pump depletion and 9.3 dB parametric gain in the 1.5 \mu m signal, which yields powers above 500 mW (3 \mu W/mode) in the idler with spectra covering 2.8 \mu m to 3.5 \mu m. Potential for broadband, high-resolution molecular spectroscopy is demonstrated by absorption spectra and interferograms obtained by heterodyning two combs.Comment: 11 pages, 8 figure

Strategi Pdam dalam Meningkatkan Kualitas Air Bersih untuk Menunjang Pembangunan di Kota Wisata Batu (Studi pada Kantor Pdam Kota Batu)

: The purposes of this research were to know the strategy used in improving clean water service in Batu and to know the supporting and inhibiting factors that influence the improvement of clean water service in Batu. This research used qualitative research method. The location of this research was in Regional Water Company (PDAM) of Batu located on Jl. Kartini No. 10. The strategy used by PDAM of Batu in improving the quality of clean water and clean water service for the population with minimum coverage of 80% was by developing the clean water sector institution then, PDAM of Batu could increase the income and improve the efficiency so that PDAM of Batu could benefit by increasing the quantity and quality of clean water services and maintain the carrying capacity of the surrounding environment. People of Batu were quite satisfied with the service provided by PDAM of Batu so far. On the other hand, PDAM of Batu has added more pipes to cover all Batu areas. Keywords: PDAM Strategy, Water Quality Improvement, Batu City Developmen

X-Ray Microscopy: Preparations for Studies of Frozen Hydrated Specimens

X-ray microscopes provide higher resolution than visible light microscopes. Wet, biological materials with a water thickness of up to about 10 μm can be imaged with good contrast using soft X-rays with wavelengths between the oxygen and carbon absorption edges (at 24 and 43 Å). The Stony Brook group has developed and operates a scanning transmission X-ray microscope (STXM) at the National Synchrotron Light Source (NSLS) at Brookhaven National Laboratory. The microscope is used for imaging with a current resolution of 50 nm, and for elemental and chemical state mapping. Radiation damage imposes a significant limitation upon high resolution X-ray microscopy of room temperature wet specimens. Experience from electron microscopy suggests that cryo techniques allow vitrified specimens to be imaged repeatedly. This is due to the increased radiation stability of biological specimens in the frozen hydrated state. Better radiation stability has been shown recently with a cryo transmission X-ray microscope developed by the University of Gottingen, operating at the BESSY storage ring in Berlin, Germany. At Stony Brook, we are developing a cryo scanning transmission X-ray microscope (CryoSTXM) to carry out imaging and spectra-microscopy experiments on frozen hydrated specimens. This article will give an outlook onto the research projects that we plan to perform using the CryoSTXM