3,803 research outputs found
City Managers, Career Incentives, and Service Delivery Decisions: The Effects of Managerial Ambition on Interlocal Cooperation Choices
City Managers are believed to play a particularly influential role in brokering cooperative service deals on behalf of their jurisdiction (Krueger and McGuire, 2005; Thurmaier and Wood, 2002; Morgan and Hirlinger, 1991), however, their motivations for doing so are not well understood. One argument, drawn from theories of bureaucratic entrepreneurship and ambition theory suggests that cities with managers who want to move up in their career will engage in more interlocal service delivery as means of capturing economic efficiencies, which helps to build their record of career achievements. An alternative theoretical argument suggests that more altruistic motives including a desire for increased social equity, and valuing the common good of the region guide, are responsible for guiding city managers decisions for interlocal cooperation. We test these competing hypotheses using survey data from 134 city managers of large municipalities, and finance data from the Historical Database of Individual Local Government Finances. We find strong support for the first theory, and no support for the alternative argument. Managerial ambition has important consequences for the rate at which cities engage in interlocal service cooperation, but local fiscal capacity also shapes these decisions. Moreover, managerial ambition has complex effects; the desire of the city manager to move onto a larger city in the near future increases the rate at which a city sells services to other local governments, but managerial career ambition decreases the rate at which cities are willing to buy services from another jurisdiction
Structural Basis for the Anomalously Low Spontaneous Polarisation Values of the Polar Phase of Sr1-xCaxTiO3 (x=0.02, 0.04): Evidence for a Ferrielectric Ordering
Full pattern Le-Bail refinement using x-ray powder diffraction profiles of
Sr1-xCaxTiO3 for x=0.02, 0.04 in the temperature range 12 to 300 K reveals
anomalies in the unit cell parameters at 170, 225 K due to an
antiferrodistortive (cubic to tetragonal I4/mcm) phase transition and at ~32,
~34 K due to a transition to a polar phase (tetragonal I4/mcm to orthorhombic
Ic2m), respectively. The lower transition temperatures obtained by us are in
excellent agreement with those reported on the basis of the dielectric studies
by Bednorz and Muller, [10] who attributed these to ferroelectric transition.
Rietveld analysis of the diffraction profiles of the polar phase reveals
off-centre displacements of both Sr2+/Ca2+ and Ti4+ ions in the X-Y plane along
pseudocubic directions, in agreement with the experimentally reported
direction of easy polarization by Bednorz and Muller, but the resulting dipole
moments are shown to be ferrielectrically coupled in the neighbouring (001)
planes along the [001] direction leading to anomalously low values of the
spontaneous polarization at 12K.Comment: 5 pages, 4 figures and 1 tabl
Premartensite to martensite transition and its implications on the origin of modulation in Ni2MnGa ferromagnetic shape memory alloy
We present here results of temperature dependent high resolution synchrotron
x-ray powder diffraction study of sequence of phase transitions in Ni2MnGa. Our
results show that the incommensurate martensite phase results from the
incommensurate premartensite phase, and not from the austenite phase assumed in
the adaptive phase model. The premartensite phase transforms to the martensite
phase through a first order phase transition with coexistence of the two phases
in a broad temperature interval (~40K), discontinuous change in the unit cell
volume as also in the modulation wave vector across the transition temperature
and considerable thermal hysteresis in the characteristic transition
temperatures. The temperature variation of the modulation wave vector q shows
smooth analytic behaviour with no evidence for any devilish plateau
corresponding to an intermediate or ground state commensurate lock-in phases.
The existence of the incommensurate 7M like modulated structure down to 5K
suggests that the incommensurate 7M like modulation is the ground state of
Ni2MnGa and not the Bain distorted tetragonal L10 phase or any other lock-in
phase with a commensurate modulation. These findings can be explained within
the framework of the soft phonon model
What do Women Want? Men, Women, and Job Satisfaction in the Public Service
Research in organizational behavior and public administration has long considered differences between men and women at work. Research indicates that men and women often communicate differently, prefer different approaches to organizational structure and design, and view rewards through different lenses. As women become better represented in public organizations, and at higher levels, it becomes even more important to explore sex-based differences. This paper seeks to uncover differences between men and women when it comes to determinants of job satisfaction. We use the existing literature to develop a series of hypotheses about the different factors that predict job satisfaction for the sexes. We test these hypotheses using data from a survey of health and human services managers, finding that there are more commonalities than differences when it comes to what satisfies men and women at work. Working Paper 06-3
Residual stress induced stabilization of martensite phase and its effect on the magneto-structural transition in Mn rich Ni-Mn-In/Ga magnetic shape memory alloys
The irreversibility of the martensite transition in magnetic shape memory
alloys (MSMAs) with respect to external magnetic field is one of the biggest
challenges that limits their application as giant caloric materials. This
transition is a magneto-structural transition that is accompanied with a steep
drop in magnetization (i.e., 'delta M') around the martensite start temperature
(Ms) due to the lower magnetization of the martensite phase. In this
communication, we show that 'delta M' around Ms in Mn rich Ni-Mn based MSMAs
gets suppressed by two orders of magnitude in crushed powders due to the
stabilization of the martensite phase at temperatures well above the Ms and the
austenite finish (Af) temperatures due to residual stresses. Analysis of the
intensities and the FWHM of the x-ray powder diffraction patterns reveals
stabilized martensite phase fractions as 97, 75 and 90% with corresponding
residual microstrains as 5.4, 5.6 and 3% in crushed powders of the three
different Mn rich Ni-Mn alloys, namely, Mn1.8Ni1.8In0.4, Mn1.75Ni1.25Ga and
Mn1.9Ni1.1Ga, respectively. Even after annealing at 773 K, the residual stress
stabilised martensite phase does not fully revert to the equilibrium cubic
austenite phase as the magneto-structural transition is only partially restored
with reduced value of 'delta M'. Our results have very significant bearing on
application of such alloys as inverse magnetocaloric and barocaloric materials
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