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What Does the Gig Economy Mean for Workers?
[Excerpt] Technological advancement and the proliferation of the smartphone have reshaped the commercial landscape, providing consumers new ways to access the retail marketplace. On-demand companies are one such innovation, and underpinning on-demand commerce is the gig economy, the collection of markets that match service providers to consumers of on-demand services on a gig (or job) basis.
Flagship on-demand companies such as Uber (driver services) and Handy (home cleaners and household services) have garnered significant media attention both for their market success and recent legal challenges, particularly concerning the classification of gig workers. Broader questions about the pros and cons of the gig economy have emerged as on-demand markets grow and the gig economy expands into new sectors. By some accounts, workers’ willingness to participate in the gig economy provides evidence that gig work is a beneficial arrangement. Indeed, gig jobs may yield benefits relative to traditional employment in terms of the ease of finding employment and greater flexibility to choose jobs and hours. The gig economy may facilitate bridge employment (e.g., temporary employment between career jobs or between full-time work and retirement) or provide opportunities to generate income when circumstances do not accommodate traditional full-time, full-year employment. At the same time, however, the potential lack of labor protections for gig workers and the precarious nature of gig work have been met with some concern.
The nationwide reach of gig work and its potential to impact large groups of workers, and their livelihoods, have attracted the attention of some Members of Congress. These Members have raised questions about the size and composition of the gig workforce, the proper classification of gig workers (i.e., as employees or independent contractors), the potential for gig work to create work opportunities for unemployed or underemployed workers, and implications of gig work for worker protections and access to traditional employment-based benefits.
In support of these policy considerations, this report provides an overview of the gig economy and identifies legal and policy questions relevant to its workforce
Development of a rotary fluid transfer coupling and support mechanism for space station
A design was developed for a rotary fluid coupling to transfer coolant fluids (primarily anhydrous ammonia) across rotating joints of the space station. Development testing using three conceptual designs yielded data which were used to establish the design of a multipass fluid coupling capable of handling three fluid circuits. In addition, a mechanism to support the fluid coupling and allow an astronaut to replace the coupling quickly and easily was designed
A -adic RanSaC algorithm for stereo vision using Hensel lifting
A -adic variation of the Ran(dom) Sa(mple) C(onsensus) method for solving
the relative pose problem in stereo vision is developped. From two 2-adically
encoded images a random sample of five pairs of corresponding points is taken,
and the equations for the essential matrix are solved by lifting solutions
modulo 2 to the 2-adic integers. A recently devised -adic hierarchical
classification algorithm imitating the known LBG quantisation method classifies
the solutions for all the samples after having determined the number of
clusters using the known intra-inter validity of clusterings. In the successful
case, a cluster ranking will determine the cluster containing a 2-adic
approximation to the "true" solution of the problem.Comment: 15 pages; typos removed, abstract changed, computation error remove
First-principle Wannier functions and effective lattice fermion models for narrow-band compounds
We propose a systematic procedure for constructing effective lattice fermion
models for narrow-band compounds on the basis of first-principles electronic
structure calculations. The method is illustrated for the series of
transition-metal (TM) oxides: SrVO, YTiO, VO, and
YMoO. It consists of three parts, starting from LDA. (i)
construction of the kinetic energy Hamiltonian using downfolding method. (ii)
solution of an inverse problem and construction of the Wannier functions (WFs)
for the given kinetic energy Hamiltonian. (iii) calculation of screened Coulomb
interactions in the basis of \textit{auxiliary} WFs, for which the
kinetic-energy term is set to be zero. The last step is necessary in order to
avoid the double counting of the kinetic-energy term, which is included
explicitly into the model. The screened Coulomb interactions are calculated in
a hybrid scheme. First, we evaluate the screening caused by the change of
occupation numbers and the relaxation of the LMTO basis functions, using the
conventional constraint-LDA approach, where all matrix elements of
hybridization involving the TM orbitals are set to be zero. Then, we switch
on the hybridization and evaluate the screening associated with the change of
this hybridization in RPA. The second channel of screening is very important,
and results in a relatively small value of the effective Coulomb interaction
for isolated bands. We discuss details of this screening and consider
its band-filling dependence, frequency dependence, influence of the lattice
distortion, proximity of other bands, and the dimensionality of the model
Hamiltonian.Comment: 35 pages, 25 figure
Instabilities and the roton spectrum of a quasi-1D Bose-Einstein condensed gas with dipole-dipole interactions
We point out the possibility of having a roton-type excitation spectrum in a
quasi-1D Bose-Einstein condensate with dipole-dipole interactions. Normally
such a system is quite unstable due to the attractive portion of the dipolar
interaction. However, by reversing the sign of the dipolar interaction using
either a rotating magnetic field or a laser with circular polarization, a
stable cigar-shaped configuration can be achieved whose spectrum contains a
`roton' minimum analogous to that found in helium II. Dipolar gases also offer
the exciting prospect to tune the depth of this `roton' minimum by directly
controlling the interparticle interaction strength. When the minimum touches
the zero-energy axis the system is once again unstable, possibly to the
formation of a density wave.Comment: 7 pages, 6 figures. Special Issue: "Ultracold Polar Molecules:
Formation and Collisions
Mode identification of Pulsating White Dwarfs using the HST
We have obtained time-resolved ultraviolet spectroscopy for the pulsating DAV
stars G226-29 and G185-32, and for the pulsating DBV star PG1351+489 with the
Hubble Space Telescope Faint Object Spectrograph, to compare the ultraviolet to
the optical pulsation amplitude and determine the pulsation indices. We find
that for essentially all observed pulsation modes, the amplitude rises to the
ultraviolet as the theoretical models predict for l=1 non-radial g-modes. We do
not find any pulsation mode visible only in the ultraviolet, nor any modes
whose phase flips by 180 degrees; in the ultraviolet, as would be expected if
high l pulsations were excited. We find one periodicity in the light curve of
G185-32, at 141 s, which does not fit theoretical models for the change of
amplitude with wavelength of g-mode pulsations.Comment: Accepted for publication in the Astrophysical Journal, Aug 200
Mesoscopic Fermi gas in a harmonic trap
We study the thermodynamical properties of a mesoscopic Fermi gas in view of
recent possibilities to trap ultracold atoms in a harmonic potential. We focus
on the effects of shell closure for finite small atom numbers. The dependence
of the chemical potential, the specific heat and the density distribution on
particle number and temperature is obtained. Isotropic and anisotropic traps
are compared. Possibilities of experimental observations are discussed.Comment: 8 pages, 9 eps-figures included, Revtex, submitted to Phys. Rev. A,
minor changes to figures and captions, corrected typo
Dissipative dynamics of vortex arrays in trapped Bose-condensed gases: neutron stars physics on K scale
We develop a theory of dissipative dynamics of large vortex arrays in trapped
Bose-condensed gases. We show that in a static trap the interaction of the
vortex array with thermal excitations leads to a non-exponential decay of the
vortex structure, and the characteristic lifetime depends on the initial
density of vortices. Drawing an analogy with physics of pulsar glitches, we
propose an experiment which employs the heating of the thermal cloud in the
course of the decay of the vortex array as a tool for a non-destructive study
of the vortex dynamics.Comment: 4 pages, revtex; revised versio
Passion at Work: A Meta-Analysis of Individual Work Outcomes
Academic research on passion is much more complex than the extant literature or popular press portray. Although research on work-related passion has progressed rapidly over the last decade, much remains unknown. We are now just beginning to recognize the different theoretical underpinnings and empirical operationalizations that work passion research has adopted, and the confusion this has generated hampers our understanding of the construct and its relationship to workplace outcomes. Accordingly, we use a meta-analytic examination to study the work-related outcomes of three dominant literature streams of work passion: general passion, dualistic passion (i.e., harmonious passion and obsessive passion), and role-based passion (i.e., passion for developing, passion for founding, and passion for inventing). We employ meta-analytic techniques using random effects modeling summarizing 106 distinct samples across 87 manuscripts totaling 384 effect sizes (total unique N = 38,481; 43.54% women, average age is 38.04). Importantly, we highlight how each of the three streams of passion relates to various outcomes differently, illuminate several important heretofore undetected nuances in passion research, and provide a roadmap for future inquiry on passion at work
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