1,389 research outputs found
Large seals fabricated from small segments reduce procurement lead time
Large diameter seals are fabricated from narrow strip stock welded in segments to form a complete ring. This technique could be used to reduce the cost of critical, large diameter seals in the heating and ventilating industry, petrochemical industry, and marine fabrication industry
Minat Memilih Profesi MedRep Ditinjau dari Persepsi dan Citra Profesi
This study examines students\u27 perceptions and brand image of MedRep as the predictors of purchase intentions for the MedRep profession. To examine the proposed research model, 100 samples are collected. Multiple regressions are used to test the hypotheses. There are mixed results in relation to the tested relationships. Brand image have a significant impact on student purchase intention for the MedRep profession. Surprisingly, analysis using the student sample indicated that students\u27 perception has no significant impact on student purchase intention for the MedRep profession
Condensation of Hard Spheres Under Gravity
Starting from Enskog equation of hard spheres of mass m and diameter D under
the gravity g, we first derive the exact equation of motion for the equilibrium
density profile at a temperature T and examine its solutions via the gradient
expansion. The solutions exist only when \beta\mu \le \mu_o \approx 21.756 in 2
dimensions and \mu_o\approx 15.299 in 3 dimensions, where \mu is the
dimensionless initial layer thickness and \beta=mgD/T. When this inequality
breaks down, a fraction of particles condense from the bottom up to the Fermi
surface.Comment: 9 pages, one figur
Investigating the pre-main sequence magnetic chemically peculiar system HD 72106
The origin of the strong magnetic fields observed in chemically peculiar Ap
and Bp stars stars has long been debated. The recent discovery of magnetic
fields in the intermediate mass pre-main sequence Herbig Ae and Be stars links
them to Ap and Bp stars, providing vital clues about Ap and Bp stars and the
origin and evolution of magnetic fields in intermediate and high mass stars. A
detailed study of one young magnetic B star, HD 72106A, is presented. This star
appears to be in a binary system with an apparently normal Herbig Ae star. A
maximum longitudinal magnetic field strength of +391 +/- 65 G is found in HD
72106A, as are strong chemical peculiarities, with photospheric abundances of
some elements ranging up to 100x above solar.Comment: 8 pages, 6 figures. Proceeding of the 2006 conference of the Special
Astrophysical Observatory of the Russian Academy of Science
Searching for Weak or Complex Magnetic Fields in Polarized Spectra of Rigel
Seventy-eight high-resolution Stokes V, Q and U spectra of the B8Iae
supergiant Rigel were obtained with the ESPaDOnS spectropolarimeter at CFHT and
its clone NARVAL at TBL in the context of the Magnetism in Massive Stars
(MiMeS) Large Program, in order to scrutinize this core-collapse supernova
progenitor for evidence of weak and/or complex magnetic fields. In this paper
we describe the reduction and analysis of the data, the constraints obtained on
any photospheric magnetic field, and the variability of photospheric and wind
lines.Comment: IAUS272 - Active OB Stars: Structure, Evolution, Mass Loss and
Critical Limit
Presenting ancient history through serious games: a case-study in Assyriology
This thesis investigates how ancient history can be effectively presented through serious games for educational purposes, by presenting a case study in the field of Assyriology. It is anticipated that the results are applicable to other fields of history and cultural heritage.
A model is presented to describe how heritage and historical content can be manifested in video games, for the design of serious games for heritage and the analysis of commercial games that present historical material.
The theories of reduced fidelity constrained virtual environments are applied to serious games for heritage, to reduce required development resources. A constrained implementation of a serious game for Assyriology is tested against an equivalent 3D environment, and results indicate the constrained environment can achieve comparable levels of presence, enjoyment, quality, and interest in the subject.
Based on an interview with an Assyriology field expert, a methodology for the analysis and design of serious games for heritage is presented, based on activity theory. The methodology is applied to the analysis and redesign of a serious game for Assyriology, and the development of a playable prototype. An online user-test showed the redesigned game was enjoyed by participants and was effective at achieving its learning objectives
Colloids in light fields: particle dynamics in random and periodic energy landscapes
The dynamics of colloidal particles in potential energy landscapes have
mainly been investigated theoretically. In contrast, here we discuss the
experimental realization of potential energy landscapes with the help of light
fields and the observation of the particle dynamics by video microscopy. The
experimentally observed dynamics in periodic and random potentials are compared
to simulation and theoretical results in terms of, e.g. the mean-squared
displacement, the time-dependent diffusion coefficient or the non-Gaussian
parameter. The dynamics are initially diffusive followed by intermediate
subdiffusive behaviour which again becomes diffusive at long times. How
pronounced and extended the different regimes are, depends on the specific
conditions, in particular the shape of the potential as well as its roughness
or amplitude but also the particle concentration. Here we focus on dilute
systems, but the dynamics of interacting systems in external potentials, and
thus the interplay between particle-particle and particle-potential
interactions, is also mentioned briefly. Furthermore, the observed dynamics of
dilute systems resemble the dynamics of concentrated systems close to their
glass transition, with which it is compared. The effect of certain potential
energy landscapes on the dynamics of individual particles appears similar to
the effect of interparticle interactions in the absence of an external
potential
PEGylation of nanoparticles improves their cytoplasmic transport
The efficacy of nucleus-targeted drug- or gene-carrying nanoparticles may be limited by slow transport through the molecularly crowded cytoplasm following endosome escape. Cytoskeletal elements and cellular organelles may pose steric and/or adhesive obstacles to the efficient intracellular transport of nanoparticles. To potentially reduce adhesive interactions of colloids with intracellular components, the surface of model nanoparticles was coated with polyethylene glycol (PEG). Subsequently, multiple-particle tracking (MPT) was used to quantify the cytoplasmic transport rates of particles microinjected into the cytoplasm of live cells. PEGylation increased average nanoparticle diffusivities by 100% compared to unPEGylated particles (time scale of 10 s) in live cells. Faster particle transport correlated with a marked decrease in the number of particles that underwent hindered transport, from 79.2% (unmodified) to 48.8% (PEGylated). This result adds to an impressive list of positive benefits associated with PEGylation of drug and gene delivery vectors
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