17,465 research outputs found
Online fundraising in the human services
This paper examines emerging possibilities for use of the Internet in human service fundraising. Human service managers must compete for limited funds with their counterparts in educational, religious, health, and other nonprofit organizations. There is enormous potential for raising funds over the Internet; yet, this approach to resource development may not be appropriate or effective in some instances for certain human service agencies. The selection of fundraising approach must be consistent with the organizational context in which it is used. This paper provides examples of cases where use of the Internet may prove to be an effective method for human service fundraising. It also examines cases where use of the Internet may not be a good match for the organizational context, whether in terms of ethics or dollars raise
Optical diffraction of focused spots and subwavelength structures
We have developed a numerical diffraction tool for cases in which the incident field is a focused spot and the diffracting structure is a single structure or an aperiodic surface. Our approach uses the integral formulation to solve Maxwell’s equations and is different from previously published methods in its choice of basis function. We compared numerical results with experimental measurements of the far-field intensity for a focused spot incident on an aluminum grating, and the comparison was favorable. Finally, we predict the diffraction behavior of the proposed digital video disk format for the next generation of optical disk. Our analysis shows that the reflected signal for this format has a strong dependence on the polarization of the incident light
Polarization quadrature measurement of subwavelength diffracting structures
The amplitude and the phase of the diffracted far field depends on polarization when the diffracting structure is comparable to or less than the wavelength. When the far-field amplitude and the phase of one polarization with respect to the orthogonal polarization is measured, small changes in the structure can be measured. To make the far-field polarization measurements, we design a detector that measures the relative polarization amplitude and the phase in quadrature. We predict numerically and verify experimentally the polarization amplitude and the phase for an optical disc and a set of gratings with varying depth. Our results show that this measurement technique is sensitive to small variations in the diffracting structure and that it can be useful in applications such as critical dimension and overlay metrology in microelectronics fabrication
University-State Child Welfare Training Partnerships: The Challenge of Matching Dollar Contributions
Universities are uniquely positioned to provide the very best training opportunities to public child welfare workers. However, university–child welfare agency training partnerships require a significant commitment of time and resources by university personnel at a time of extensive state cuts to public higher education. This national survey of university partnership administrators found significant differences among university respondents involving length of the contractual relationship, matching dollar requirements, and overall satisfaction with the training partnership
Stabilization of Ab Initio Molecular Dynamics Simulations at Large Time Steps
The Verlet method is still widely used to integrate the equations of motion
in ab initio molecular dynamics simulations. We show that the stability limit
of the Verlet method may be significantly increased by setting an upper limit
on the kinetic energy of each atom with only a small loss in accuracy. The
validity of this approach is demonstrated for molten lithium fluoride.Comment: 9 pages, 3 figure
Plane wave/pseudopotential implementation of excited state gradients in density functional linear response theory: a new route via implicit differentiation
This work presents the formalism and implementation of excited state nuclear
forces within density functional linear response theory (TDDFT) using a plane
wave basis set. An implicit differentiation technique is developed for
computing nonadiabatic coupling between Kohn-Sham molecular orbital
wavefunctions as well as gradients of orbital energies which are then used to
calculate excited state nuclear forces. The algorithm has been implemented in a
plane wave/pseudopotential code taking into account only a reduced active
subspace of molecular orbitals. It is demonstrated for the H and N
molecules that the analytical gradients rapidly converge to the exact forces
when the active subspace of molecular orbitals approaches completeness
What motivates African-American charitable giving: findings from a national sample
Given the growing wealth of minority families in America, including that of African-American families, the potential for charitable donations from these households is much greater. The purpose of this secondary analysis is to examine those variables that may influence African-American charitable giving patterns. This study uses the Panel Study of Income Dynamics (PSID) data to analyze the effects of multiple factors on the giving habits of African-Americans. Based on this study\u27s findings, social workers employed as executive directors or fund-raisers in private nonprofit organizations may want to identify and cultivate individual African-American donors directly, instead of relying on United Way and other federated campaigns
Ideal, Defective, and Gold--Promoted Rutile TiO2(110) Surfaces: Structures, Energies, Dynamics, and Thermodynamics from PBE+U
Extensive first principles calculations are carried out to investigate
gold-promoted TiO2(110) surfaces in terms of structure optimizations,
electronic structure analyses, ab initio thermodynamics calculations of surface
phase diagrams, and ab initio molecular dynamics simulations. All computations
rely on density functional theory in the generalized gradient approximation
(PBE) and account for on-site Coulomb interactions via inclusion of a Hubbard
correction, PBE+U, where U is computed from linear response theory. This
approach is validated by investigating the interaction between TiO2(110)
surfaces and typical probe species (H, H2O, CO). Relaxed structures and binding
energies are compared to both data from the literature and plain PBE results.
The main focus of the study is on the properties of gold-promoted titania
surfaces and their interactions with CO. Both PBE+U and PBE optimized
structures of Au adatoms adsorbed on stoichiometric and reduced TiO2 surfaces
are computed, along with their electronic structure. The charge rearrangement
induced by the adsorbates at the metal/oxide contact are also analyzed and
discussed. By performing PBE+U ab initio molecular dynamics simulations, it is
demonstrated that the diffusion of Au adatoms on the stoichiometric surface is
highly anisotropic. The metal atoms migrate either along the top of the
bridging oxygen rows, or around the area between these rows, from one bridging
position to the next along the [001] direction. Approximate ab initio
thermodynamics predicts that under O-rich conditions, structures obtained by
substituting a Ti5c atom with an Au atom are thermodynamically stable over a
wide range of temperatures and pressures.Comment: 20 pages, 12 figures, accepted for publication in Phys. Rev.
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