Sound propagation in and radiation from acoustically lined flow ducts: A comparison of experiment and theory

The results of an experimental and theoretical study of many of the fundamental details of sound propagation in hard wall and soft wall annular flow ducts are reported. The theory of sound propagation along such ducts and the theory for determining the complex radiation impedance of higher order modes of an annulus are outlined, and methods for generating acoustic duct modes are developed. The results of a detailed measurement program on propagation in rigid wall annular ducts with and without airflow through the duct are presented. Techniques are described for measuring cut-on frequencies, modal phase speed, and radial and annular mode shapes. The effects of flow velocity on cut-on frequencies and phase speed are measured. Comparisons are made with theoretical predictions for all of the effects studies. The two microphone method of impedance is used to measure the effects of flow on acoustic liners. A numerical study of sound propagation in annular ducts with one or both walls acoustically lined is presented

Sediment budget possibilities and improbabilities

Problems of constructing a sediment budget for an inlet is often a challenge due to constraints on data collection, quality of data, and assumptions one is willing to consider. Existing literature does not provide a systematic foundation for equations considered and often engineers and geologists typically do not properly consider the mathematical constraints placed on the problem of sediment budget construction. The present technical note presents a simple methodology for assessing sediment budget, i.e. what is possible, and what is not possible via a matrix equation system and linear algebra. It is hoped that engineers and geologists will not impose unrealistic expectations on the sediment budget system via using such an approach. Some simple examples are given of both pitfalls and correct approaches to sediment budget development

Gold-Catalyzed Intramolecular Aminoarylation of Alkenes: C-C Bond Formation through Bimolecular Reductive Elimination

Gold-ilocks and the 3 mol % catalyst: Bimetallic gold bromides allow the room temperature aminoarylation of unactivated terminal olefins with aryl boronic acids using Selectfluor as an oxidant. A catalytic cycle involving gold(I)/gold(III) and a bimolecular reductive elimination for the key CC bond-forming step is proposed. dppm= bis(diphenylphosphanyl)methane

Effect of Energy Source Prior to Parturitian and During Lactation on Tissue Lipid, Liver Glycogen and Plasma Levels of Some Metabolytes in the Newborn Pig

Two experiments were conducted to determine the effect of energy source (carbohydrate or fat), fed to sows prior to parturition and during lactation, on energy storage and some metabolite levels in the neonatal pig which may exert an influence on rate of survival

Effect of Energy Source Prior to Parturitian and During Lactation on Tissue Lipid, Liver Glycogen and Plasma Levels of Some Metabolytes in the Newborn Pig

Two experiments were conducted to determine the effect of energy source (carbohydrate or fat), fed to sows prior to parturition and during lactation, on energy storage and some metabolite levels in the neonatal pig which may exert an influence on rate of survival

Deployable-erectable trade study for space station truss structures

The results of a trade study on truss structures for constructing the space station are presented. Although this study was conducted for the reference gravity gradient space station, the results are generally applicable to other configurations. The four truss approaches for constructing the space station considered in this paper were the 9 foot single fold deployable, the 15 foot erectable, the 10 foot double fold tetrahedral, and the 15 foot PACTRUSS. The primary rational for considering a 9 foot single-fold deployable truss (9 foot is the largest uncollapsed cross-section that will fit in the Shuttle cargo bay) is that of ease of initial on-orbit construction and preintegration of utility lines and subsystems. The primary rational for considering the 15 foot erectable truss is that the truss bay size will accommodate Shuttle size payloads and growth of the initial station in any dimension is a simple extension of the initial construction process. The primary rational for considering the double-fold 10 foot tetrahedral truss is that a relatively large amount of truss structure can be deployed from a single Shuttle flight to provide a large number of nodal attachments which present a pegboard for attaching a wide variety of payloads. The 15 foot double-fold PACTRUSS was developed to incorporate the best features of the erectable truss and the tetrahedral truss

Soybean, 1962-1966

Cover title."University of Missouri Agricultural Experiment Station in cooperation with Agricultural Research Service, U.S. Dept. Agriculture.

PRUDENT AND IMPRUDENT USE OF ANTLERLESS MOOSE HARVESTS IN INTERIOR ALASKA

Liberal antlerless moose (Alces alces) hunts which allow the take of substantial numbers of largely female moose have been controversial and divisive since the Alaska Department of Fish and Game instituted ill-timed, liberal antlerless hunts in the early 1970s that contributed to a precipitous population decline. Thus, we initially found the governing, citizen (non-agency) advisory committees largely skeptical of implementing liberal antlerless harvests in the early 2000s in Game Management Unit 20A (Unit 20A). To help justify the hunts, we focused on presenting information about the notably low nutritional status of the current moose population relative to moose populations worldwide. However, to gain broader credibility and trust, we needed to directly address public perceptions regarding former “mismanagement” of antlerless hunts, including admitting past mistakes that contributed to long-term poor hunting opportunities. We subsequently presented major differences between recent antlerless hunts and those in the 1970s. Specifically, we contrasted relevant circumstances between the 2 time periods, including moose population trajectories, harvest rates of males and females, survey techniques and related technology, winter severity and frequency, and reproductive rates. Illustrating the major, time-period differences in these parameters was key to assuring the public that harvest of female moose could be prudent. By directly addressing public anxieties, we were successful in gaining and maintaining public support for liberal antlerless hunts in Unit 20A. Subsequently, our success in Unit 20A has helped ease recent expansion of antlerless hunts into adjacent areas

PRUDENT AND IMPRUDENT USE OF ANTLERLESS MOOSE HARVESTS IN INTERIOR ALASKA

Liberal antlerless moose (Alces alces) hunts which allow the take of substantial numbers of largely female moose have been controversial and divisive since the Alaska Department of Fish and Game instituted ill-timed, liberal antlerless hunts in the early 1970s that contributed to a precipitous population decline. Thus, we initially found the governing, citizen (non-agency) advisory committees largely skeptical of implementing liberal antlerless harvests in the early 2000s in Game Management Unit 20A (Unit 20A). To help justify the hunts, we focused on presenting information about the notably low nutritional status of the current moose population relative to moose populations worldwide. However, to gain broader credibility and trust, we needed to directly address public perceptions regarding former “mismanagement” of antlerless hunts, including admitting past mistakes that contributed to long-term poor hunting opportunities. We subsequently presented major differences between recent antlerless hunts and those in the 1970s. Specifically, we contrasted relevant circumstances between the 2 time periods, including moose population trajectories, harvest rates of males and females, survey techniques and related technology, winter severity and frequency, and reproductive rates. Illustrating the major, time-period differences in these parameters was key to assuring the public that harvest of female moose could be prudent. By directly addressing public anxieties, we were successful in gaining and maintaining public support for liberal antlerless hunts in Unit 20A. Subsequently, our success in Unit 20A has helped ease recent expansion of antlerless hunts into adjacent areas