1,274 research outputs found
Building Workplace Democracy
This project seeks to understand how members of an organization transition from a centralized power structure to organizational democracy. Worker cooperatives, credit unions, grocery cooperatives, professional partnerships, and utility cooperatives are all examples of democratically governed organizations, where formal power is evenly distributed across the membership. Democratic organizations are often touted as an exemplary form of socially responsible business, as they have been shown to expand access to market opportunities, reduce poverty, improve wages, and increase employment stability, among various socially beneficial outcomes. Yet, the relative rarity of organizational democracy, the importance of strong leadership in organizations, and the tendency for hierarchy to emerge in growing organizations leave us with little understanding of the processes with which democratic organizations emerge. In this project, I will use ethnographic methods, quantitative text analysis, and qualitative video analysis to inductively develop theory about the emergence of organizational democracy. I will study a nascent democratic organization in Pittsburgh, where I have negotiated permission to collect audio and video recordings of meetings, interview workers, observe the day-to-day life of the organization, access archival documents, and scrape chat data from their online platform. I have been collecting preliminary, background data in this organization since 2018. In 2020, I will engage in a one year period of intensive data collection. I will hire and train an undergraduate research assistant who will participate in the firm’s daily life and collect data. I will also set up a video and audio recording system that the company has agreed to operate during its meetings, so that we are able to collect data when we are not present. The company is motivated to set up this system as a means to improve governance and increase transparency with worker owners. Ultimately, this project will serve as a proof of concept for future data collection. A city-wide taskforce has been established and funded to build the population of democratic organizations in the City of Pittsburgh. If this project is successful, as a member of the taskforce, I will expand this data collection to the broader set of nascent firms
Analysis of a risk based model for the growth of AIDS infection
Several models for the spread of AIDS within a homosexual community have been proposed that incorporate biased mixing of different risk groups. A simple model is presented that captures many of the features of these more complex models. Analytical expressions are derived for the time to the state of maximum infection (SMI) in a particular risk group, the proportion infected at SMI, and the number of infected individuals as the group approaches SMI. These results agree qualitatively with numerical simulations of the model
A new double coronary artery anomaly: The right coronary artery originating above the coronary sinus giving off the circumflex artery
This is the first reported case of a coronary artery anomaly in which the right coronary artery originates above the left sinus of Valsalva and also gives off the circumflex system. Use of the aortogram and careful inspection of the ventriculogram in the right anterior oblique view were most helpful in recognizing the anomaly. The potential pathologic significance of the anomaly and pitfalls of misdiagnosis are discussed
Ground state of the random-bond spin-1 Heisenberg chain
Stochastic series expansion quantum Monte Carlo is used to study the ground
state of the antiferromagnetic spin-1 Heisenberg chain with bond disorder.
Typical spin- and string-correlations functions behave in accordance with
real-space renormalization group predictions for the random-singlet phase. The
average string-correlation function decays algebraically with an exponent of
-0.378(6), in very good agreement with the prediction of , while the average spin-correlation function is found to decay with an
exponent of about -1, quite different from the expected value of -2. By
implementing the concept of directed loops for the spin-1 chain we show that
autocorrelation times can be reduced by up to two orders of magnitude.Comment: 9 pages, 10 figure
Response to Comments on Young-Hyman et al. Psychosocial Care for People With Diabetes: A Position Statement of the American Diabetes Association. Diabetes Care 2016;39:2126-2140
Numerical studies of the two- and three-dimensional gauge glass at low temperature
We present results from Monte Carlo simulations of the two- and
three-dimensional gauge glass at low temperature using the parallel tempering
Monte Carlo method. Our results in two dimensions strongly support the
transition being at T_c=0. A finite-size scaling analysis, which works well
only for the larger sizes and lower temperatures, gives the stiffness exponent
theta = -0.39 +/- 0.03. In three dimensions we find theta = 0.27 +/- 0.01,
compatible with recent results from domain wall renormalization group studies.Comment: 7 pages, 10 figures, submitted to PR
Random-field-driven phase transitions in the ground state of the S=1 XXZ spin chain
Ground-state of the S=1 XXZ spin chain under the influence of the random
magnetic field is studied by means of the exact-diagonalization method. The
S=1/2 counterpart has been investigated extensively so far. The easy-plane
area, including the Haldane and the XY phases, is considered. The area suffers
significantly from the magnitude of the constituent spin. Destruction of the
Haldane state is observed at a critical strength of the random field, which is
comparable to the magnitude of the Haldane gap. This transition is
characterized by the disappearance of the string order. The XY region continues
until at a critical randomness, at which a transition of the KT-universality
class occurs. These features are contrasted with those of the S=1/2
counterpart
Dynamics and transport in random quantum systems governed by strong-randomness fixed points
We present results on the low-frequency dynamical and transport properties of
random quantum systems whose low temperature (), low-energy behavior is
controlled by strong disorder fixed points. We obtain the momentum and
frequency dependent dynamic structure factor in the Random Singlet (RS) phases
of both spin-1/2 and spin-1 random antiferromagnetic chains, as well as in the
Random Dimer (RD) and Ising Antiferromagnetic (IAF) phases of spin-1/2 random
antiferromagnetic chains. We show that the RS phases are unusual `spin metals'
with divergent low-frequency spin conductivity at T=0, and we also follow the
conductivity through novel `metal-insulator' transitions tuned by the strength
of dimerization or Ising anisotropy in the spin-1/2 case, and by the strength
of disorder in the spin-1 case. We work out the average spin and energy
autocorrelations in the one-dimensional random transverse field Ising model in
the vicinity of its quantum critical point. All of the above calculations are
valid in the frequency dominated regime \omega \agt T, and rely on previously
available renormalization group schemes that describe these systems in terms of
the properties of certain strong-disorder fixed point theories. In addition, we
obtain some information about the behavior of the dynamic structure factor and
dynamical conductivity in the opposite `hydrodynamic' regime for
the special case of spin-1/2 chains close to the planar limit (the quantum x-y
model) by analyzing the corresponding quantities in an equivalent model of
spinless fermions with weak repulsive interactions and particle-hole symmetric
disorder.Comment: Long version (with many additional results) of Phys. Rev. Lett. {\bf
84}, 3434 (2000) (available as cond-mat/9904290); two-column format, 33 pages
and 8 figure
Frustrated two-dimensional Josephson junction array near incommensurability
To study the properties of frustrated two-dimensional Josephson junction
arrays near incommensurability, we examine the current-voltage characteristics
of a square proximity-coupled Josephson junction array at a sequence of
frustrations f=3/8, 8/21, 0.382 , 2/5, and 5/12.
Detailed scaling analyses of the current-voltage characteristics reveal
approximately universal scaling behaviors for f=3/8, 8/21, 0.382, and 2/5. The
approximately universal scaling behaviors and high superconducting transition
temperatures indicate that both the nature of the superconducting transition
and the vortex configuration near the transition at the high-order rational
frustrations f=3/8, 8/21, and 0.382 are similar to those at the nearby simple
frustration f=2/5. This finding suggests that the behaviors of Josephson
junction arrays in the wide range of frustrations might be understood from
those of a few simple rational frustrations.Comment: RevTex4, 4 pages, 4 eps figures, to appear in Phys. Rev.
Current--Voltage Characteristics of Two--Dimensional Vortex Glass Models
We have performed Monte Carlo simulations to determine current--voltage
characteristics of two different vortex glass models in two dimensions. The
results confirm the conclusions of earlier studies that there is a transition
at . In addition we find that, as , the linear resistance vanishes
exponentially, and the current scale, , where non-linearities appear in
the -- characteristics varies roughly as , quite different from the
predictions of conventional flux creep theory, . The results for
the two models agree quite well with each other, and also agree fairly well
with recent experiments on very thin films of YBCO.Comment: 18 pages with 10 figures available upon request from R. A. Hyman at
[email protected]. The only change in the new version is the
deletion of an unimportant comment.IUCM94-01
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