1,874 research outputs found
A Common Tragedy: Condemnation and the Anticommons
Abstract: Economic development of land may be suboptimal where multiple parties have the legal right to exclude use of the property in question. Michael Heller labeled this phenomenon the ‘anticommons.’ It has been argued that condemnation of private property for economic development is a potentially efficiency-enhancing solution to the anticommons problem. Until recently, this argument was largely academic. However, with the recent Supreme Court decision in Kelo v. City of New London, condemnation for economic development is now a valid policy choice. In this paper, I argue that the economic models used to justify condemnation are fundamentally flawed and that the use of condemnation for economic development encroaches upon autonomy interests without promoting efficiency interests
Using XDAQ in Application Scenarios of the CMS Experiment
XDAQ is a generic data acquisition software environment that emerged from a
rich set of of use-cases encountered in the CMS experiment. They cover not the
deployment for multiple sub-detectors and the operation of different processing
and networking equipment as well as a distributed collaboration of users with
different needs. The use of the software in various application scenarios
demonstrated the viability of the approach. We discuss two applications, the
tracker local DAQ system for front-end commissioning and the muon chamber
validation system. The description is completed by a brief overview of XDAQ.Comment: Conference CHEP 2003 (Computing in High Energy and Nuclear Physics,
La Jolla, CA
Exploring Metacognition as a Support for Learning Transfer
The ability to transfer learning to new situations lies at the heart of lifelong learning and the employability of university graduates. Because students are often unaware of the importance of learning transfer and staff do not always explicitly articulate this expectation, this article explores the idea that metacognition (intentional awareness and the use of that awareness) might enhance the development of learning transfer. Our exploratory study includes results from a survey of 74 staff and 118 students from five institutions in Australia, Belgium, UK, and USA. Our data indicate that many staff and a majority of students do not have a clear understanding of what learning transfer entails, and that there are many mismatches between staff and student perceptions, attitudes, and behaviors regarding learning transfer. This helps explain why learning transfer does not occur as often as it could. We found significant positive correlations between thinking about transfer and thinking about learning processes and the likelihood to use awareness to guide practice. These support the idea that metacognition might enhance learning transfer. We offer suggestions for future scholarship of teaching and learning
The CMS Event Builder
The data acquisition system of the CMS experiment at the Large Hadron
Collider will employ an event builder which will combine data from about 500
data sources into full events at an aggregate throughput of 100 GByte/s.
Several architectures and switch technologies have been evaluated for the DAQ
Technical Design Report by measurements with test benches and by simulation.
This paper describes studies of an EVB test-bench based on 64 PCs acting as
data sources and data consumers and employing both Gigabit Ethernet and Myrinet
technologies as the interconnect. In the case of Ethernet, protocols based on
Layer-2 frames and on TCP/IP are evaluated. Results from ongoing studies,
including measurements on throughput and scaling are presented.
The architecture of the baseline CMS event builder will be outlined. The
event builder is organised into two stages with intelligent buffers in between.
The first stage contains 64 switches performing a first level of data
concentration by building super-fragments from fragments of 8 data sources. The
second stage combines the 64 super-fragments into full events. This
architecture allows installation of the second stage of the event builder in
steps, with the overall throughput scaling linearly with the number of switches
in the second stage. Possible implementations of the components of the event
builder are discussed and the expected performance of the full event builder is
outlined.Comment: Conference CHEP0
Reformulating the Schrodinger equation as a Shabat-Zakharov system
We reformulate the second-order Schrodinger equation as a set of two coupled
first order differential equations, a so-called "Shabat-Zakharov system",
(sometimes called a "Zakharov-Shabat" system). There is considerable
flexibility in this approach, and we emphasise the utility of introducing an
"auxiliary condition" or "gauge condition" that is used to cut down the degrees
of freedom. Using this formalism, we derive the explicit (but formal) general
solution to the Schrodinger equation. The general solution depends on three
arbitrarily chosen functions, and a path-ordered exponential matrix. If one
considers path ordering to be an "elementary" process, then this represents
complete quadrature, albeit formal, of the second-order linear ODE.Comment: 18 pages, plain LaTe
A compact statistical model of the song syntax in Bengalese finch
Songs of many songbird species consist of variable sequences of a finite
number of syllables. A common approach for characterizing the syntax of these
complex syllable sequences is to use transition probabilities between the
syllables. This is equivalent to the Markov model, in which each syllable is
associated with one state, and the transition probabilities between the states
do not depend on the state transition history. Here we analyze the song syntax
in a Bengalese finch. We show that the Markov model fails to capture the
statistical properties of the syllable sequences. Instead, a state transition
model that accurately describes the statistics of the syllable sequences
includes adaptation of the self-transition probabilities when states are
repeatedly revisited, and allows associations of more than one state to the
same syllable. Such a model does not increase the model complexity
significantly. Mathematically, the model is a partially observable Markov model
with adaptation (POMMA). The success of the POMMA supports the branching chain
network hypothesis of how syntax is controlled within the premotor song nucleus
HVC, and suggests that adaptation and many-to-one mapping from neural
substrates to syllables are important features of the neural control of complex
song syntax
Heterogeneous Rates of Time Preference and the Decision to Smok
Individuals with higher personal rates of time preference will be more likely to smoke. Although previous studies have found no evidence of a relationship between smoking and rates of time preference, analysis of implicit rates of time preference associated with workers\u27 wage fatality risk trade-offs indicates that smokers have higher rates of time preference with respect to years of life. Current smokers have an implied rate of time preference of 13.8% as compared to 8.1% for nonsmokers. Current smokers who are blue-collar workers have rates of time preference with respect to years of life of 16.3% compared to 7.8% for nonsmoking blue-collar workers
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