Quality measurements of an UWB reduced-size CPW-fed aperture antenna

The paper presents a characterization of a compact co-planar waveguide (CPW)-fed slot loaded low return loss planar printed antenna designed for wireless communication and ultra-wideband (UWB) applications. Following a review of the antenna design, which was implemented and simulated using Agilent's Advanced Design System (ADS), the paper presents laboratory measurements of relative gain and impulse response transformed from the frequency domain. An antenna quality metric based on time-domain S21 is discussed and related to antenna quality metrics such as the System Fidelity Factor (SFF)

X-ray Emission from Extragalactic Jets

This review focuses on the X-ray emission processes of extra-galactic jets on scales resolvable by the sub arcsec resolution of the Chandra X-ray Observatory. It is divided into 4 parts. The introductory chapter reviews the classical problems for jets, as well as those associated directly with the X-ray emission. Throughout this section, we deal with the dualisms of low powered radio sources versus high powered radio galaxies and quasars; synchrotron models versus inverse Compton models; and the distinction between the relativistic plasma responsible for the received radiation and the medium responsible for the transport of energy down the jet. The second part collects the observational and inferred parameters for the currently detected X-ray jets and attempts to put their relative sizes and luminosities in perspective. In part 3, we first give the relevant radio and optical jet characteristics, and then examine the details of the X-ray data and how they can be related to various jet attributes. The last section is devoted to a critique of the two non-thermal emission processes and to prospects for progress in our understanding of jets.Comment: This is a version of a review article to be published (2006 Sep) in the Annual Reviews of Astronomy and Astrophysics, vol. 44, p. 463. 8 of the 12 figures have been removed from the article and are provided as separate jpg files to conserve space. There are 38 pages remaining in the text. Complete postscript and pdf versions are available at: http://hea-www.harvard.edu/~harris/Xjetreview

Structural optimization by generalized, multilevel decomposition

The developments toward a general multilevel optimization capability and results for a three-level structural optimization are described. The method partitions a structure into a number of substructuring levels where each substructure corresponds to a subsystem in the general case of an engineering system. The method is illustrated by a portal framework that decomposes into individual beams. Each beam is a box that can be further decomposed into stiffened plates. Substructuring for this example spans three different levels: (1) the bottom level of finite elements representing the plates; (2) an intermediate level of beams treated as substructures; and (3) the top level for the assembled structure. The three-level case is now considered to be qualitatively complete

Application of multidisciplinary optimization methods to the design of a supersonic transport

An optimization design method is discussed. This method is based on integrating existing disciplinary analysis and sensitivity analysis techniques by means of generalized sensitivity equations. A generic design system implementing this method is described. The system is being used to design the configuration and internal structure of a supersonic transport wing for optimum performance. This problem combines the disciplines of linear aerodynamics, structures, and performance. Initial results which include the disciplines of aerodynamics and structures in a conventional minimum weight design under static aeroelastic constraints are presented

Oscillatory oblique stagnation-point flow toward a plane wall

Two-dimensional oscillatory oblique stagnation-point flow toward a plane wall is investigated. The problem is a eneralisation of the steady oblique stagnation-point flow examined by previous workers. Far from the wall, the flow is composed of an irrotational orthogonal stagnation-point flow with a time-periodic strength, a simple shear flow of constant vorticity, and a time-periodic uniform stream. An exact solution of the Navier-Stokes equations is sought for which the flow streamfunction depends linearly on the coordinate parallel to the wall. The problem formulation reduces to a coupled pair of partial differential equations in time and one spatial variable. The first equation describes the oscillatory orthogonal stagnation-point flow discussed by previous workers. The second equation, which couples to the first, describes the oblique component of the flow. A description of the flow velocity field, the instantaneous streamlines, and the particle paths is sought through numerical solutions of the governing equations and via asymptotic analysis

Antimicrobial Susceptibilities of Aerobic Isolates from Respiratory Samples of Young New Zealand Horses

3rd Annual IEEE Energy Conversion Congress and Exposition, ECCE 2011, Phoenix, AZ, 17-22 September 2011This paper presents a method of mitigating the transient overshoots of DC-DC converters operating with large load disturbances. The method involves a small auxiliary power circuit with a complementary control scheme that provides a smooth absorption and release of excess energy from and to the main DC-DC converter in the events of large load changes. This control mechanism interactively mitigates the large transient overshoots which would otherwise appear at the converter output. Since the control scheme involves an adjustable-energy-storage feature, the proposed solution is effective for any level of step-load change within a pre-specified range.Department of Electronic and Information EngineeringRefereed conference pape

Copper and zinc nutrition experimental results.

Long term copper trial - Newdegate research station, 66N14. Copper, zinc and sulphur residual with DAP for wheat, 78WH66. Copper and zinc residual with dap 78Mo36. Zinc residual with high analysis n.p. fertiliser for wheat 80no31. Zinc residual with high analysis n.p. fertiliser for wheat 79me22, 79me23. Zinc residual with high analysis n.p. fertiliser for wheat 82mo8. Zinc, copper and sulphur residual with DAP, 781G27. Methods of copper application on new land, 85JE48. Evaluation of copper ore 85LG47. Zinc by nitrogen interaction, 85LG28. Zinc residual with DAP, 85LG29. Copper sulphate, copper chelate and copper oxychloride effectiveness for wheat, 85LG26. Zinc sulphate, zinc chelate sprays on wheat, 85LG

Trace element nutrition

South Perth Long term copper trial - Newdegate Research Station – 66N14. Copper, zinc & sulphur residual with DAP for wheat – 78WH66. Copper and zinc residual with DAP – 78MO36. Zinc residual with high analysis N.P. fertilizer for wheat – 79ME22, 79ME23, 80MO8, 80NO31. Cereal responses to zinc Copper and nitrogen interactions on wheat varieties – 83GE2, 83WH1. Barley responses to drilled trace elements – 83BR4, 83BR5. Manganese on wheat – 82NO8. ESPERANCE Zinc residual with high analysis N.P. fertilizer for wheat – 83ES35. Methods of copper application on new land – 83LG6. Copper spray and nitrogen rate applications to wheat supplied with super, copper, zinc and molybdenum no. 1 – 83LG4. Copper sprays on wheat – 84LG3. Zinc sulphate, zinc chelate sprays on wheat – 84LG4. Nitrogen and Hoegrass@ on zinc nutrition of wheat grown on heavy land – 84LG30. Hoegrass@ on zinc nutrition of wheat varieties – 84LGX

Estimating Modified Duration and Convexity for Income Properties

Some institutions hold income producing properties directly as part of an investment portfolio. These properties are subject to interest rate risk. The two widely used measures of interest rate risk are modified duration and convexity. These measures can be difficult to calculate directly for income properties when net operating income and cash flows are not constant or when they are functions of the underlying yield. A numerical technique using sensitivity analysis is developed to provide estimates of modified duration and convexity. These estimates can then be used, along with corresponding values for debt, to determine the modified duration and convexity of the equity of the property. This can be extended to a portfolio of properties. The measurement of the interest rate risk of the equity of a portfolio of properties, using conventional interest rate risk measures, has a number of useful applications