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Identity-driven cooperation versus competition
This paper seeks to extend the domain of identity economics by exploring motivational foundations of in-group cooperation and out-group competition. On this basis, we explore the reflexive interaction between individual economic decisions and social identities in response to technological change in market economies. Our analysis explores how technological change falling on marketable goods and services, rather than non-market caring relationships, leads to a restructuring of identities, which increases the scope of individualism and promotes positional competition at the expense of caring activities. Since positional competition generates negative externalities while caring activities create positive ones, these developments have important welfare implications
Algebraic, geometric, and stochastic aspects of genetic operators
Genetic algorithms for function optimization employ genetic operators patterned after those observed in search strategies employed in natural adaptation. Two of these operators, crossover and inversion, are interpreted in terms of their algebraic and geometric properties. Stochastic models of the operators are developed which are employed in Monte Carlo simulations of their behavior
Mycorrhizal colonization of Hypericum perforatum L. (Hypericaceae) on adjacent serpentine and granite outcrops on the Deer Isles, Maine, USA
Given the paucity of literature on plant-fungal interactions on serpentine soils and limited investigation of serpentine geoecology in eastern North America, we examined mycorrhizal colonization of Hypericum perforatum from adjacent serpentine and granite outcrops on the Deer Isles, ME to determine whether plants were differentially colonized based on substrate. We coincided our sampling with three phenologic stages of H. perforatum (preflowering, flowering, postflowering) to determine possible differences in colonization based on plant phenology. The levels of mycorrhizal colonization in H. perforatum were not significantly different between serpentine and granite sites, while levels of colonization in postflowering plants were significantly higher than in those at preflowering and flowering stages
ORBIT: The Oregon Road Base Information Team, A Draft Summary Report
It is clear that transportation organizations across the nation are integrating GIS into operations at many different levels—from day to day use for data display, to full-scale enterprise level integration for operations, inventory management, research and a variety of other purposes. The cost of building and maintaining a current and accurate GIS database can be substantial within any given organization. For some smaller level organizations—small counties, cities or special districts, the cost of gathering data, organizing it and implementing systems within expensive software on an expensive operating platform can be downright discouraging. Also, as more complex data structures are accumulated a window for more comprehensive modeling and analysis of regional issues is opened. Each of these trends alone provide ample incentive to develop data standards that can be applied to all systems to facilitate data sharing between organizations for system development, system update, or project specific purposes. Taken together these trends provide an imperative to develop data-sharing standards
Excited state preparation of trapped ultracold atoms via swept potentials
We study the out-of-equilibrium dynamics of non-interacting atoms confined
within a one-dimensional harmonic trap triggered by dragging an external
long-range potential through the system. The symmetry-breaking nature of this
moving potential couples adjacent eigenstates in the atoms' effective
potential, leading to an energy landscape reminscent of systems exhibiting
trap-induced shape resonances. These couplings may be exploited to selectively
excite the atoms into higher vibrational states of the harmonic trap by
controlling the motion of the dragged potential. To this end, we consider two
protocols designs: the first protocol strives to maintain adiabaticity at
critical points during the atoms' dynamics, whilst the second protocol utilises
the fast tunnelling of the atoms within their effective double-well potential.
These protocols take place in the few to many millisecond regime and achieve
high-fidelity excitation of the atoms into pure vibrational states and
superpositions thereof. Overall, our study highlights the significance of
dragged potentials for controlling and manipulating atom dynamics and offers
intuitive protocols for achieving desired excitations
Doing research in immigration removal centres: ethics, emotions and impact
Immigration Removal Centres (IRCs) are deeply contested institutions that rarely open their doors to independent research. In this article we discuss some of the complications we faced in conducting the first national study of everyday life in them. As we will set out, research relationships were difficult to forge due to low levels of trust, and unfamiliarity with academic research. At the same time, many participants had unrealistic expectations about our capacity to assist while most exhibited high levels of distress. We were not immune from the emotional burden of the field sites. Such matters were compounded by the limited amount of published information about life in IRCs and a lack of ethical guidelines addressing such places. Drawing on related literature from prison sociology, we use our experiences in IRCs to set out a methodological account of understanding, ethics, and impact within these complex sites
Tailored Excitation for Multivariable Stability-Margin Measurement Applied to the X-31A Nonlinear Simulation
Safety and productivity of the initial flight test phase of a new vehicle have been enhanced by developing the ability to measure the stability margins of the combined control system and vehicle in flight. One shortcoming of performing this analysis is the long duration of the excitation signal required to provide results over a wide frequency range. For flight regimes such as high angle of attack or hypersonic flight, the ability to maintain flight condition for this time duration is difficult. Significantly reducing the required duration of the excitation input is possible by tailoring the input to excite only the frequency range where the lowest stability margin is expected. For a multiple-input/multiple-output system, the inputs can be simultaneously applied to the control effectors by creating each excitation input with a unique set of frequency components. Chirp-Z transformation algorithms can be used to match the analysis of the results to the specific frequencies used in the excitation input. This report discusses the application of a tailored excitation input to a high-fidelity X-31A linear model and nonlinear simulation. Depending on the frequency range, the results indicate the potential to significantly reduce the time required for stability measurement
Immigration Detention: Perspectives from Maine Law Students Working on the Ground at the Laredo Detention Center in Texas
Since 2017, students enrolled in the University of Maine School of Law Refugee and Human Rights Clinic have traveled to Laredo, Texas to participate in a program, sponsored and run by the law firm Jones Day in collaboration with Texas RioGrande Legal Aid, to provide representation for women in the Laredo Detention Center. Alongside Jones Day attorneys, the students conduct client intake interviews, draft memos detailing each woman’s experiences and any potential legal claims, and assist in the representation of clients. This article will provide a glimpse into the experiences of three Maine Law student attorneys during their time in Laredo, Texas, and will survey issues in the contemporary immigration landscape: first, an overview of the political climate surrounding the immigration debate, current immigration trends, and statistical figures; second, stories providing context for why people are seeking to immigrate to the U.S., and the persecution and challenges faced by immigrant women; third, the shortage of representation for immigrants, whether detained or non-detained; and finally, one of the most challenging and poignant issues encountered by student attorneys participating in the Laredo Project—the separation of immigrant mothers from their children
Welding the Space Station Common Module Prototype
The NASA Manned Space Flight program planned for the 1990\u27 s is directed towards the commercial use of space through development of large space structures serving a variety of missions. The diversity of the program, and the demands of the mission tasks requires a thorough understanding of the mission requirements and the requirements for subsystems which are readily adaptable to a wide range of applications.
The heart of the NASA Space Station is the common module; a light weight, thin walled pressure vessel that can be configured for a wide range of functions: i.e., laboratories, manufacturing facilities, living quarters, and cargo carriers. Before the space station is placed in orbit, development articles must be built and tested, design issues must be resolved, manufacturing problems overcome and accurate cost information generated
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