285 research outputs found
Do Institutions Really Matter? Assessing the Impact of State Judicial Structures on Citizen Litigiousness
The Conditional Effects of Ideology and Institutional Structure on Judicial Voting in State Supreme Courts
Two enormously influential perspectives on courts offer fundamentally different predictions about court outcomes and the effects of judge ideology on those outcomes. Well-known to political scientists studying courts, the ideological voting (IV) literature argues that judge ideology is a strong predictor of court outcomes and that those outcomes should be proximate to the policy preferences of courts. Less known to political scientists but highly influential, the law and economics perspective (LE) focuses on settlement behavior of litigants who try to minimize costs and thus estimate likely outcomes in court, and settle simpler cases pre-trial. In this case selection process litigants respond to cues that signal likely outcomes with the result that only complex, less predictable cases make it to trial leading to win-rates that coalesce at fifty percent for plaintiffs or defendants. From this perspective, litigant strategies cancel out the effects of judge ideology and court outcomes do not correspond to judges’ ideological preferences. We reconcile these perspectives by examining tort cases in state supreme courts from 1995 through 1998. The contrasting perspectives stem from the fundamental institutional processes upon which each perspective is based. The LE perspective dominates in states without lower appellate courts (LAC) where process of appeal in these state supreme courts is litigant-driven, with win-rates hovering at fifty percent and deviations from that norm accounted for by forces influencing litigant uncertainty. The ideological voting predicted by the IV literature occurs primarily in the context of state supreme court strategic reversals of LAC decisions---a process commensurate that operating with the U.S. Supreme Court. When it comes to judicial outcomes, institutional structure is a critical element shaping the influence of litigant strategy and judge ideology
Development and Validation of a Model for Centrifugal Compressors in Reversed Flow Regimes
Turbochargers are widely used to help reduce the environmental impact of automotive engines. However, a limiting factor for turbochargers is compressor surge. Surge is an instability that induces pressure and flow oscillations that often damages the turbocharger and its installation. Most predictions of the surge limit are based on low-order models, such as the Moore-Greitzer model. These models tend to rely on a characteristic curve for the compressor created by extrapolating the constant speed lines of a steady-state compressor map into the negative mass flow region. However, there is little validation of these assumptions in the public literature. In this article, we develop further the first-principles model for a compressor characteristic presented in Powers, K., Brace, C., Budd, C., Copeland, C., & Milewski, P., 2020, "Modeling Axisymmetric Centrifugal Compressor Characteristics From First Principles," J. Turbomachinery, 142(9), with a particular emphasis on reverse flow. We then perform experiments using a 58 mm diameter centrifugal compressor provided by Cummins Turbo Technologies, where we feed air in the reverse direction though the compressor while the impeller is spinning in the forward direction to obtain data in the negative mass flow region of the compressor map. This demonstrated experimentally that there is a stable operating region in the reverse flow regime. The recorded data showed a good match with the theoretical model developed in this article. We also identified a change in characteristic behavior as the impeller speed is increased, which, to the authors' knowledge, has not been observed in any previously published experimental work.</p
Modeling Axisymmetric Centrifugal Compressor Characteristics from First Principles
Turbochargers are a vital component for aiding engine manufacturers in meeting the latest emissions standards. However, their range of operation is limited for low mass flows by compressor surge. Operation in surge results in pressure and mass flow oscillations that are often damaging to the compressor and its installation. Since surge is a highly complex flow regime, full unsteady 3D models are generally too computationally expensive to run. The majority of current low-dimensional surge models use a cubic compressor characteristic that needs to be fitted to experimental data. Therefore, each time a compressor is studied using these models, costly experimental testing is required.In this paper, a new technique for obtaining an axisymmetric centrifugal compressor characteristic is presented. This characteristic is built using the equations of mass, momentum and energy from first principles in order to provide a more complete model than those currently obtained via experimental data. This approach enables us to explain the resulting cubic-like shape of the characteristic and hence to identify impeller inlet stall as a route into surge. The characteristic is used within a quasi-steady, map-based surge model in order to demonstrate its ability to predict the onset of surge while only providing geometric data as input. Validation is provided for this model by discussion of the qualitative flow dynamics and a good fit to experimental data, especially for low impeller speeds and pressure ratios
Divergent evolutionary processes associated with colonization of offshore islands
Peer reviewedPublisher PD
The Grizzly, August 29, 2000
UC Class of \u2704: Welcome to a Journey of a Lifetime • Campus Security puts Safety First • Students React to Parking Fee Increase • Chemistry Course Canceled • UC Gets Wired: New Laptop Program Debuts • Opinion: What This Campus Really Needs; Tuition Rises, Why Not Scholarships?; Campaign 2000: Bush, Gore and so Much More • Making the Most of Your Ursinus Experience • Commuters are Students Too!! • Upperclassman Reflects on First Days of a New Life at UC • Finding a New Home at UC • Food for Thought: Eating Right at Wismer • Getting Involved in UC Clubs, Organizations • CIE: One Student\u27s Perspective • UC Student to Appear on Jeopardy! • Field Hockey Team set for Breakout Season • Football Program Looks to Build on Success • Men\u27s Soccer Program On the Rise • Women\u27s Program Looking to Score Big • Volleyball Team Set to Kill Competition • XC Squad, After False Start, Ready to Run • No Routine Season for Cheerleading Squad • Field House Construction Behind Schedule • UC Grad Brackin Earns Post-Grad Scholarshiphttps://digitalcommons.ursinus.edu/grizzlynews/1469/thumbnail.jp
Self-Duality of a Topologically Massive Born-Infeld Theory
We consider self-duality in a 2+1 dimensional gauge theory containing both
the Born-Infeld and the Chern-Simons terms. We introduce a Born-Infeld inspired
generalization of the Proca term and show that the corresponding self dual
equation is identical to that of the Born-Infeld-Chern-Simons theory.Comment: 10 Pages, Accepted in Phys. Lett. B, New results and references adde
Picturing Efficiency: Precisionism, Scientific Management, and the Effacement of Labor
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