1,666 research outputs found
The Coming Asian Pacific Community and its Implications for Planning : An Open Opportunity
In an era when a European Community and a North American free trade bloc are being formed, there is a basis for dreaming of an Asian Pacific Community. Experience obtained thus far shows that trade becomes a minor part of the overall integration required to maintain a peaceable, stable Community while enhancing the cultural and social exchange. The amount of negotiation required is several orders of magnitude greater than the present capability, investments must be made in recruiting talent and training it. Human resource development and institution building that penetrates all the participating countries will require the most time. A handful of Asian institutions presently, have trans-national coverage but there are gaps in the coverage of the management of modern technology, environment, and planning. A prototype proposal is offered for getting started in a strategic way. It would create a micro-community of predoctorate and post-doctorate fellows in planning at one or two sites that are least limited by library constraints
Hydrogenation of CO on a silica surface: an embedded cluster approach
The sequential addition of H atoms to CO adsorbed on a siliceous edingtonite surface is studied with an embedded cluster approach, using density functional theory for the quantum mechanical (QM) cluster and a molecular force field for the molecular mechanical (MM) cluster. With this setup, calculated QM/MM adsorption energies are in agreement with previous calculations employing periodic boundary conditions. The catalytic effect of the siliceous edingtonite (100) surface on CO hydrogenation is assessed because of its relevance to astrochemistry. While adsorption of CO on a silanol group on the hydroxylated surface did not reduce the activation energy for the reaction with a H atom, a negatively charged defect on the surface is found to reduce the gas phase barriers for the hydrogenation of both CO and H2C = O. The embedded cluster approach is shown to be a useful and flexible tool for studying reactions on (semi-)ionic surfaces and specific defects thereon. The methodology presented here could easily be applied to study reactions on silica surfaces that are of relevance to other scientific areas, such as biotoxicity of silica dust and geochemistry
Refining the vulnerability model of low self-esteem and depression: Disentangling the effects of genuine self-esteem and narcissism.
Effect size guidelines for cross-lagged effects
Cross-lagged models are by far the most commonly used method to test the prospective effect of one construct on another, yet there are no guidelines for interpreting the size of cross-lagged effects. This research aims to establish empirical benchmarks for cross-lagged effects, focusing on the cross-lagged panel model (CLPM) and the random intercept cross-lagged panel model (RI-CLPM). We drew a quasirepresentative sample of studies published in four subfields of psychology (i.e., developmental, socialâpersonality, clinical, and industrialâorganizational). The dataset included 1,028 effect sizes for the CLPM and 302 effect sizes for the RI-CLPM, based on data from 174 samples. For the CLPM, the 25th, 50th, and 75th percentiles of the distribution corresponded to cross-lagged effect sizes of .03, .07, and .12, respectively. For the RI-CLPM, the corresponding values were .02, .05, and .11. Effect sizes did not differ significantly between the CLPM and RI-CLPM. Moreover, effect sizes did not differ significantly across subfields and were not moderated by design characteristics. However, effect sizes were moderated by the concurrent correlation between the constructs and the stability of the predictor. Based on the findings, we propose to use .03 (small effect), .07 (medium effect), and .12 (large effect) as benchmark values when interpreting the size of cross-lagged effects, for both the CLPM and RI-CLPM. In addition to aiding in the interpretation of results, the present findings will help researchers plan studies by providing information needed to conduct power analyses and estimate minimally required sample sizes
Josephson dynamics for coupled polariton modes under the atom-field interaction in the cavity
We consider a new approach to the problem of Bose-Einstein condensation (BEC)
of polaritons for atom-field interaction under the strong coupling regime in
the cavity. We investigate the dynamics of two macroscopically populated
polariton modes corresponding to the upper and lower branch energy states
coupled via Kerr-like nonlinearity of atomic medium. We found out the
dispersion relations for new type of collective excitations in the system under
consideration. Various temporal regimes like linear (nonlinear) Josephson
transition and/or Rabi oscillations, macroscopic quantum self-trapping (MQST)
dynamics for population imbalance of polariton modes are predicted. We also
examine the switching properties for time-averaged population imbalance
depending on initial conditions, effective nonlinear parameter of atomic medium
and kinetic energy of low-branch polaritons.Comment: 10 pages, 6 postscript figures, uses svjour.cl
Tips for implementing multigrid methods on domains containing holes
As part of our development of a computer code to perform 3D `constrained
evolution' of Einstein's equations in 3+1 form, we discuss issues regarding the
efficient solution of elliptic equations on domains containing holes (i.e.,
excised regions), via the multigrid method. We consider as a test case the
Poisson equation with a nonlinear term added, as a means of illustrating the
principles involved, and move to a "real world" 3-dimensional problem which is
the solution of the conformally flat Hamiltonian constraint with Dirichlet and
Robin boundary conditions. Using our vertex-centered multigrid code, we
demonstrate globally second-order-accurate solutions of elliptic equations over
domains containing holes, in two and three spatial dimensions. Keys to the
success of this method are the choice of the restriction operator near the
holes and definition of the location of the inner boundary. In some cases (e.g.
two holes in two dimensions), more and more smoothing may be required as the
mesh spacing decreases to zero; however for the resolutions currently of
interest to many numerical relativists, it is feasible to maintain second order
convergence by concentrating smoothing (spatially) where it is needed most.
This paper, and our publicly available source code, are intended to serve as
semi-pedagogical guides for those who may wish to implement similar schemes.Comment: 18 pages, 11 figures, LaTeX. Added clarifications and references re.
scope of paper, mathematical foundations, relevance of work. Accepted for
publication in Classical & Quantum Gravit
Spin dynamics of molecular nanomagnets fully unraveled by four-dimensional inelastic neutron scattering
Molecular nanomagnets are among the first examples of spin systems of finite
size and have been test-beds for addressing a range of elusive but important
phenomena in quantum dynamics. In fact, for short-enough timescales the spin
wavefunctions evolve coherently according to the an appropriate cluster
spin-Hamiltonian, whose structure can be tailored at the synthetic level to
meet specific requirements. Unfortunately, to this point it has been impossible
to determine the spin dynamics directly. If the molecule is sufficiently
simple, the spin motion can be indirectly assessed by an approximate model
Hamiltonian fitted to experimental measurements of various types. Here we show
that recently-developed instrumentation yields the four-dimensional
inelastic-neutron scattering function S(Q,E) in vast portions of reciprocal
space and enables the spin dynamics to be determined with no need of any model
Hamiltonian. We exploit the Cr8 antiferromagnetic ring as a benchmark to
demonstrate the potential of this new approach. For the first time we extract a
model-free picture of the quantum dynamics of a molecular nanomagnet. This
allows us, for example, to examine how a quantum fluctuation propagates along
the ring and to directly test the degree of validity of the
N\'{e}el-vector-tunneling description of the spin dynamics
Polarization state of the optical near-field
The polarization state of the optical electromagnetic field lying several
nanometers above complex dielectric structures reveals the intricate
light-matter interaction that occurs in this near-field zone. This information
can only be extracted from an analysis of the polarization state of the
detected light in the near-field. These polarization states can be calculated
by different numerical methods well-suited to near--field optics. In this
paper, we apply two different techniques (Localized Green Function Method and
Differential Theory of Gratings) to separate each polarisation component
associated with both electric and magnetic optical near-fields produced by
nanometer sized objects. The analysis is carried out in two stages: in the
first stage, we use a simple dipolar model to achieve insight into the physical
origin of the near-field polarization state. In the second stage, we calculate
accurate numerical field maps, simulating experimental near-field light
detection, to supplement the data produced by analytical models. We conclude
this study by demonstrating the role played by the near-field polarization in
the formation of the local density of states.Comment: 9 pages, 11 figures, accepted for publication in Phys. Rev.
Ursinus College Alumni Journal, August 1967
Exposure \u2767 Ursinus ⢠Viewpoint at commencement time: Means to an end; Toward freedom; Liberal morality; Open-minded attitude; Quality vs. quantity ⢠From the President ⢠What makes Suzy a language dud? ⢠The paradox of urbia: an interview ⢠Negro voices of the city ⢠Springtime was alumni time ⢠Dr. Myers wins alumni award ⢠Dr. Wessel speaks on urbia ⢠Alumni giving climbs in 1967 ⢠Campus clippings: Collegeville area grows; Staigers tour world; Color film; Miss congeniality; New Board members; Placement service; Schultze promoted; Humble gift; Include Ursinus in your will ⢠Sporting scene: Tennis; Baseball; Track ⢠Anatomy of medical school life ⢠Class notebook ⢠Faculty members speak at spring regional meetings ⢠Weddings ⢠Births ⢠In memoriam ⢠Physicians Club meets â˘https://digitalcommons.ursinus.edu/alumnijournal/1089/thumbnail.jp
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