5,627 research outputs found
Chain: A Dynamic Double Auction Framework for Matching Patient Agents
In this paper we present and evaluate a general framework for the design of
truthful auctions for matching agents in a dynamic, two-sided market. A single
commodity, such as a resource or a task, is bought and sold by multiple buyers
and sellers that arrive and depart over time. Our algorithm, Chain, provides
the first framework that allows a truthful dynamic double auction (DA) to be
constructed from a truthful, single-period (i.e. static) double-auction rule.
The pricing and matching method of the Chain construction is unique amongst
dynamic-auction rules that adopt the same building block. We examine
experimentally the allocative efficiency of Chain when instantiated on various
single-period rules, including the canonical McAfee double-auction rule. For a
baseline we also consider non-truthful double auctions populated with
zero-intelligence plus"-style learning agents. Chain-based auctions perform
well in comparison with other schemes, especially as arrival intensity falls
and agent valuations become more volatile
Impact of Industrial Disasters on the Mental Health of Vietnamese Americans on the Gulf Coast
An explosion on the Deepwater Horizon oil rig caused 200 million gallons of crude oil to spill on the Gulf Coast over a five-month span. About 16,000 miles of coastline, ecosystem and marine life along Alabama, Florida, Louisiana, Mississippi, and Texas were contaminated. This disaster and the recovery process caused social, financial, and ecological shocks, resulting in adverse psychosocial and physical health outcomes, health disparities, and socioeconomic inequality. Among the oil spill\u27s most affected and vulnerable populations are the Vietnamese American communities that settled on the Gulf Coast after the end of the Vietnam War in 1975. The plight of Vietnamese refugees was nothing short of accumulated trauma from experiencing forced migration, displacement, pirate attacks on sea, starvation, and drowning. This re-traumatization from their historical trauma, exacerbated by the impact of man-made disasters, leaves many Vietnamese Americans at a severe mental health risk and navigating limited access to Vietnamese language resources and treatment plans. The core of mental health practices has historically been guided by European colonial and imperialist hegemony resulting in racialized assessments, misdiagnoses, and ineffective pathways to recovery among Asian Americans. Therefore, Westernized intervention programs are inadequate in addressing the complexity of the re-traumatization of Vietnamese Americans. Adapted from Decolonizing Mental Health Practices Framework for Asian Americans of Millner et al., 2021, the framework incorporates a Vietnamese American-centered framework that addresses the historical trauma from war and displacement
Exploring Decolonial and Indigenous mental health framework and practice to address complex trauma among Palestinian youth living under violence of settler-colonialism
The growing settler colonial project of Israel forced indigenous Palestinians to flee from their homeland to further the Zionist movement of establishing a Jewish-majority state. The forced dispossession and displacement of Palestinians at this time was referred to as the Nakba, or catastrophe (Masalha, 2002). From 1947 and 1949, approximately 750,000 Palestinians from a population of 1.9 million were made refugees (Al Jazeera, 2017). Also referred to as the ethnic cleansing of Palestine, Zionists forcibly took over 78 percent of Palestine, destroyed about 530 villages and cities, and killed around 15,000 Palestinians including more than 70 massacres (Al Jazeera, 2017). Since October 7th, 2023, Palestinians have continued to be under violent besiegement of the Israeli occupation through carpet bombings, forced starvation, aid deprivation, and massacres. Current figures still do not reflect an accurate number of Palestinian child fatalities in both Gaza and the West Bank. Palestinian youth have been forced to live under violent occupation since they were born and have been reported to live with psychosocial challenges due to the conditions brought upon by Israeli occupation. According to Dr. Samah Jabr, the Palestinian head of mental health services, she described how there is no “post” in Palestinian youth facing trauma because it is never-ending. Furthermore, she continues how Westernized clinical definitions of mental health do not apply to the experiences of Palestinians (Goldhill, 2019). In exploring decolonial and Indigenous mental health frameworks and practices, how can they address the complex historical trauma of the ongoing violence of settler-colonialism among Palestinian youth
The Taurus Boundary of Stellar/Substellar (TBOSS) Survey I: far-IR disk emission measured with Herschel
With Herschel/PACS 134 low mass members of the Taurus star-forming region
spanning the M4-L0 spectral type range and covering the transition from low
mass stars to brown dwarfs were observed. Combining the new Herschel results
with other programs, a total of 150 of the 154 M4-L0 Taurus members members
have observations with Herschel. Among the 150 targets, 70um flux densities
were measured for 7 of the 7 ClassI objects, 48 of the 67 ClassII members, and
3 of the 76 ClassIII targets. For the detected ClassII objects, the median 70um
flux density level declines with spectral type, however, the distribution of
excess relative to central object flux density does not change across the
stellar/substellar boundary in the M4-L0 range. Connecting the 70um TBOSS
values with the results from K0-M3 ClassII members results in the first
comprehensive census of far-IR emission across the full mass spectrum of the
stellar and substellar population of a star-forming region, and the median flux
density declines with spectral type in a trend analogous to the flux density
decline expected for the central objects. SEDs were constructed for all TBOSS
targets covering the optical to far-IR range and extending to the submm/mm for
a subset of sources. Based on an initial exploration of the impact of different
physical parameters; inclination, scale height and flaring have the largest
influence on the PACS flux densities. From the 24um to 70um spectral index of
the SEDs, 5 new candidate transition disks were identified. The steep 24um to
70um slope for a subset of 8 TBOSS targets may be an indication of truncated
disks in these systems.Two examples of mixed pair systems that include
secondaries with disks were measured. Finally, comparing the TBOSS results with
a Herschel study of Ophiuchus brown dwarfs reveals a lower fraction of disks
around the Taurus substellar population.Comment: 64 pages, 33 figures, 12 tables, accepted for publication in A&
Distinct order of Gd 4f and Fe 3d moments coexisting in GdFe4Al8
Single crystals of flux-grown tetragonal GdFe4Al8 were characterized by
thermodynamic, transport, and x-ray resonant magnetic scattering measurements.
In addition to antiferromagnetic order at TN ~ 155 K, two low-temperature
transitions at T1 ~ 21 K and T2 ~ 27 K were identified. The Fe moments order at
TN with an incommensurate propagation vector (tau,tau,0) with tau varying
between 0.06 and 0.14 as a function of temperature, and maintain this order
over the entire T<TN range. The Gd 4f moments order below T2 with a
ferromagnetic component mainly out of plane. Below T1, the ferromagnetic
components are confined to the crystallographic plane. Remarkably, at low
temperatures the Fe moments maintain the same modulation as at high
temperatures, but the Gd 4f moments apparently do not follow this modulation.
The magnetic phase diagrams for fields applied in [110] and [001] direction are
presented and possible magnetic structures are discussed.Comment: v2: 14 pages, 12 figures; PRB in prin
Particle distribution and nuclear stopping in Au-Au collisions at =200 GeV
The transverse momentum distribution of produced charged particles is
investigated for gold-gold collisions at GeV. A simple
parameterization is suggested for the particle distribution based on the
nuclear stopping effect. The model can fit very well both the transverse
momentum distributions at different pseudo-rapidities and the pseudo-rapidity
distributions at different centralities. The ratio of rapidity distributions
for peripheral and central collisions is calculated and compared with the data.Comment: 5 pages in RevTeX, 3 eps figure
Efficiently Clustering Very Large Attributed Graphs
Attributed graphs model real networks by enriching their nodes with
attributes accounting for properties. Several techniques have been proposed for
partitioning these graphs into clusters that are homogeneous with respect to
both semantic attributes and to the structure of the graph. However, time and
space complexities of state of the art algorithms limit their scalability to
medium-sized graphs. We propose SToC (for Semantic-Topological Clustering), a
fast and scalable algorithm for partitioning large attributed graphs. The
approach is robust, being compatible both with categorical and with
quantitative attributes, and it is tailorable, allowing the user to weight the
semantic and topological components. Further, the approach does not require the
user to guess in advance the number of clusters. SToC relies on well known
approximation techniques such as bottom-k sketches, traditional graph-theoretic
concepts, and a new perspective on the composition of heterogeneous distance
measures. Experimental results demonstrate its ability to efficiently compute
high-quality partitions of large scale attributed graphs.Comment: This work has been published in ASONAM 2017. This version includes an
appendix with validation of our attribute model and distance function,
omitted in the converence version for lack of space. Please refer to the
published versio
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