Muskrat Ramble

Fergus was a Swede, and he\u27d been trapping Iowa marshes and streams for most of his fifty-five years. His hands showed the scars he\u27d earned learning how not to handle muskrats, and his fingers were swollen from years of plunging them into half-frozen water to make a set or recover a trap..

Conservation Pricing Of Household Water Use In Public Water Systems In Georgia's Coastal Communities: A Preliminary Exploration

The purpose of this study is to explore the effect of price on residential water use in public water supply systems in Georgia's Coastal region. Particular attention is focused on measures for the elasticity of demand for residential water use inasmuch as a showing of price inelasticity may make the wider adoption of conservation pricing more palatable to small communities with concerns that raising water prices will reduce much-needed revenues.To clarify the nature and importance of the elasticity measure, consider the following simplified example. A community sells 100 units of water for $1.00 per unit. Its' total revenues are$100. Suppose price is increased by 20% to $1.20, and that the units purchased falls by 30$84.00. In this case, we say that demand is "elastic;" the quantity of water used by folks "stretches" relative to the change in price. With elastic demand, rising prices mean lower total revenues. Suppose, however, that with the 20% price increase, demand fell to only 90 units -- a 10% decrease. Total revenues are now $108. In this case we say demand is inelastic -- quantity doesn't really "stretch" much when prices rise. If demand is inelastic, rising prices means higher revenues.From our limited, phase one efforts in these regards, we use aggregate water pricing data from 50 public water supply systems in 28 coastal counties that participated in a survey conducted during late the period 2003-2005. We find strong evidence that, at the margin, residential water use is indeed affected by prices charged for water in this region. We also find what we regard to be reasonably compelling evidence suggesting that residential water demand is inelastic over the range of marginal prices observed in our sample. This latter finding suggests that the use of conservation pricing as a tool for water conservation may not have an adverse effect on community revenues. Indeed, it may well be the case that increasing water prices will increase, not decrease, the community's revenues from the sale of water.In moving to phase two of this work, a great more will be accomplished in terms of refinements in the nature and quality of data used; greater efforts will be placed on attempts to identify functional forms that will yield best estimates for residential water demand in the state. Our ultimate goal is to be capable of responding to the needs of Georgia communities in the coastal region for information related to how one might improve the design of a community's water rate structure, and to conservation pricing policies that will best serve their interests and the interests of the state. Working Paper Number 2005-00

Performance of transducers with segmented piezoelectric stacks using materials with high electromechanical coupling coefficient

Underwater acoustic transducers often include a stack of thickness polarized piezoelectric material pieces of alternating polarity interspersed with electrodes, bonded together and electrically connected in parallel. The stack is normally much shorter than a quarter wavelength at the fundamental resonance frequency, so that the mechanical behavior of the transducer is not affected by the segmentation. When the transducer bandwidth is less than a half octave, as has conventionally been the case, stack segmentation has no significant effect on the mechanical behavior of the device. However, when a high coupling coefficient material such as PMN-PT is used to achieve a wider bandwidth, the difference between a segmented stack and a similar piezoelectric section with electrodes only at the two ends can be significant. This paper investigates the effects of stack segmentation on the performance of wideband underwater acoustic transducers, particularly tonpilz transducer elements. Included is discussion of transducer designs using single crystal piezoelectric material with high coupling coefficient compared with more traditional PZT ceramics.Comment: 26 pages including 14 figures, one table and one appendi

Did the pre-1980 use of instream structures improve streams? A reanalysis of historic data

In the 1930s, after only three years of scientific investigation at the University of Michigan Institute for Fisheries Research, cheap labor and government-sponsored conservation projects spearheaded by the Civilian Conservation Corps allowed the widespread adoption of in-stream structures throughout the United States. From the 1940s through the 1970s, designs of in-stream structures remained essentially unchanged, and their use continued. Despite a large investment in the construction of in-stream structures over these four decades, very few studies were undertaken to evaluate the impacts of the structures on the channel and its aquatic populations. The studies that were undertaken to evaluate the impact of the structures were often flawed. The use of habitat structures became an ‘‘accepted practice,’’ however, and early evaluation studies were used as proof that the structures were beneficial to aquatic organisms. A review of the literature reveals that, despite published claims to the contrary, little evidence of the successful use of in-stream structures to improve fish populations exists prior to 1980. A total of 79 publications were checked, and 215 statistical analyses were performed. Only seven analyses provide evidence for a benefit of structures on fish populations, and five of these analyses are suspect because data were misclassified by the original authors. Many of the changes in population measures reported in early publications appear to result from changes in fishing pressure that often accompanied channel modifications. Modern evaluations of channel-restoration projects must consider the influence of fishing pressure to ensure that efforts to improve fish habitat achieve the benefits intended. My statistical results show that the traditional use of in-stream structures for channel restoration design does not ensure demonstrable benefits for fish communities, and their ability to increase fish populations should not be presumed

Social Choice and Cultural Bias

These three essays are the fruits of a little Winter Study, in December 1981, which enabled Mary Douglas and James Douglas (both of Northwestern University, Illinois, USA) to visit the System and Decision Sciences area at IIASA, there to collaborate on an interdisciplinary (or, more properly, non-disciplinary) task. 'Institutional bias' was the provisional title for what we had in mind and our aim was to try to wrap some cultural and political context around the paradoxes of social choice. The Western liberal tradition holds rationality and individuality in high regard. It has to; otherwise it would not be liberal, nor would it cohere long enough to become a tradition. But too high a regard for reason may exaggerate the part played by conscious design in the conduct of human affairs, and too high a regard for the individual may exaggerate both his ability to identify the things that he values and his scope to arrange them in an order of his own choosing. The unity of these essays lies in their common critical theme; all three, in their different ways, take issue with the liberal tradition. James Douglas' point of departure is the recognition that actual political systems coped very effectively with the paradoxes of social choice long before Condorcet and Arrow revealed that those paradoxes existed. Since they could not have been consciously designed to do this, these systems must have evolved. The lowly dung beetle, as it decides whether to try to find a new and untenanted cow-pat or to stick with the ever crustier one that it has, follows a personal strategy so subtle as to require integral calculus in its solution. Could it be that we are no better equipped to design our political institutions than is the dung beetle up to doing 'A level' mathematics? Trial and error -- success and failure over countless generations -- we conclude, is what has led the individual dung beetle to the so-sensible strategy that it shares with every other dung beetle. The rational-choice theorist, if he could bring himself to study so distasteful a subject, would have to conclude that, with such a lack of variation in the preference orderings of cow-pats as we go from one individual to another, there is some form of dictatorship operating within the dung beetles' social system. Of course, in the dung beetle case, the lack of individuality -- the dictatorship -- is about as extreme as it could possibly be and it would be foolish to pretend that it provides a more valid model of human social life than does the theory of rational choice. No, our aim is not to jump to the dung beetle's extreme but, rather, to ask: 'extreme from what?' The answer has to be: 'from a situation in which, because the individual preference orderings are so gloriously varied that no parallelisms -- no little clumpings or mutual alignments -- can exist, there can be no dictatorship'. We would argue that such a situation, though intellectually intriguing, has nothing to do with the description of the life of man in society...apart, that is, from saying that it is not like that. The "invisible dictators"' that the rational-choice theorist conjures up in response to the parallelisms -- the departures from individual perfection -- that he continually bumps up against are, collectively, an old friend of the anthropologist. They are culture. The only trouble is that invisible dictators are plural and culture is singular. To resolve this paradox we begin by defining our extreme at the opposite pole to that defined by the theory of rational choice. Instead of the fine independence of the individual we take as our model the dung beetle. 'To what extent, and in what ways, does our behavior distance us from it?' we ask, rather than 'to what extent does our behavior fall short of the individualist ideal?'. But are not these differences, like a knot in a length of string, simply different ways of measuring the same thing? No, because there is no continuum -- no measuring scale -- between these two extremes. Total dictatorship is attainable; perfect individuality is not. We can measure our divergence from the attainable but not from the unattainable, and the attempt to do the latter we label 'the individualist fallacy ' . The dung beetle has, over the generations, adapted so as to take advantage of the adoptive possibilities of an environment within which certain laws (such as the progressive drying out of cow-pats) hold inexorable sway. In much the same way, actual political systems have evolved to take advantage of an environment wherein Arrow's impossibility theorem holds away. But what is particularly interesting is that, though all these systems cope with the paradoxes of social choice, they do not all cope with them in the same way. Mary Douglas comes in at this point and, venturing into the untrodden terrain that lies between cultural anthropology and organization theory, sketches out a three-fold typology of socially viable organizations, each one of which stabilizes itself with the aid of its appropriate and distinctive cultural bias. So it is culture -- man's self-reflexive ability -- that distances him from the dung beetle. At the same time, this idea of cultural biases stabilizing their appropriate social organizations ('departures from individual perfection' from the rational-choice viewpoint) allows us to reconcile a plurality of invisible dictators with a singular culture. The final essay explores the way in which these two levels -- the cultural biases that always intervene to prevent the attainment of perfect individuality and the political systems that cope with the paradoxes of social choice -- fit together. Cultural biases, it argues, are in perpetual contention. One organizational form may, for a time, gain dominance but it can never permanently eliminate the others. Within this flux certain conjunctions of cultural biases (and of their associated organizations) are stabilizable (or, at any rate, change only in slow time) and these persistent regularities we label 'political regimes

Verification of a Decision Level Fusion Algorithm Using a Proven ATR System and Measured SAR Data

Decision level fusion (DLF) algorithms combine outputs of multiple single sensors to make one confident declaration of a target. This research compares performance results of a DLF algorithm using measured data and a proven ATR system with results from simulated data and a modeled ATR system. This comparison indicates that DLF offers significant performance improvements over single sensor looks. However, results based on simulated data and a modeled ATR are slightly optimistic and overestimate results from measured data and a proven ATR system by nearly 10% over all targets tested

Douglas B. Thompson in a Senior Baritone Recital

This is the program for the senior baritone recital of Douglas B. Thompson. Mr. Thompson was accompanied on the piano by Camille Brown. This recital took place on October 5, 2001, in the McBeth Recital Hall in the Mabee Fine Arts Center

Robustness of the Thirty Meter Telescope Primary Mirror Control System

The primary mirror control system for the Thirty Meter Telescope (TMT) maintains the alignment of the 492 segments in the presence of both quasi-static (gravity and thermal) and dynamic disturbances due to unsteady wind loads. The latter results in a desired control bandwidth of 1Hz at high spatial frequencies. The achievable bandwidth is limited by robustness to (i) uncertain telescope structural dynamics (control-structure interaction) and (ii) small perturbations in the ill-conditioned influence matrix that relates segment edge sensor response to actuator commands. Both of these effects are considered herein using models of TMT. The former is explored through multivariable sensitivity analysis on a reduced-order Zernike-basis representation of the structural dynamics. The interaction matrix ("A-matrix") uncertainty has been analyzed theoretically elsewhere, and is examined here for realistic amplitude perturbations due to segment and sensor installation errors, and gravity and thermal induced segment motion. The primary influence of A-matrix uncertainty is on the control of "focusmode"; this is the least observable mode, measurable only through the edge-sensor (gap-dependent) sensitivity to the dihedral angle between segments. Accurately estimating focus-mode will require updating the A-matrix as a function of the measured gap. A-matrix uncertainty also results in a higher gain-margin requirement for focus-mode, and hence the A-matrix and CSI robustness need to be understood simultaneously. Based on the robustness analysis, the desired 1 Hz bandwidth is achievable in the presence of uncertainty for all except the lowest spatial-frequency response patterns of the primary mirror

Quantification of three-dimensional folding using fluvial terraces: A case study from the Mushi anticline, northern margin of the Chinese Pamir

Fold deformation in three dimensions involves shortening, uplift, and lateral growth. Fluvial terraces represent strain markers that have been widely applied to constrain a fold's shortening and uplift. For the lateral growth, however, the utility of fluvial terraces has been commonly ignored. Situated along northern margin of Chinese Pamir, the Mushi anticline preserves, along its northern flank, flights of passively deformed fluvial terraces that can be used to constrain three-dimensional folding history, especially lateral growth. The Mushi anticline is a geometrically simple fault-tip fold with a total shortening of 740?±?110?m and rock uplift of ~1300?m. Geologic and geomorphic mapping and dGPS surveys reveal that terrace surfaces perpendicular to the fold's strike display increased rotation with age, implying the fold grows by progressive limb rotation. We use a pure-shear fault-tip fold model to estimate a uniform shortening rate of 1.5?+?1.3/?0.5?mm/a and a rock-uplift rate of 2.3?+?2.1/?0.8?mm/a. Parallel to the fold's strike, longitudinal profiles of terrace surfaces also display age-dependent increases in slopes. We present a new model to distinguish lateral growth mechanisms (lateral lengthening and/or rotation above a fixed tip). This model indicates that eastward lengthening of the Mushi anticline ceased by at least ~134?ka and its lateral growth has been dominated by rotation. Our study confirms that terrace deformation along a fold's strike not only can constrain the lateral lengthening rate but can serve to quantify the magnitude and rate of lateral rotation: attributes that are commonly difficult to define when relying on other geomorphic criteria