A dynamic conductance model of fluorescent lamp for electronic ballast design simulation

A Spice-compatible dynamic conductance model of a fluorescent lamp for use in electronic ballast simulation is presented. The time-dependent conductance of the fluorescent lamp is derived from a plasma ionization balance equation that uses simplified descriptions of the physical processes within the lamp as its basis. The model has been designed to enable user-defined lamp radius, length, buffer gas pressure and cold-spot temperature as input parameters thus representing a valuable tool for ballast simulations. Simulation results are compared to experimental measurements and satisfactory agreement is achieved

The Struggle between the Domestic and Desire : Bourgeois Women’s Role in the Modern Market

The Industrial Revolution brought with it changes in manufacturing, advertising and social order, which in turn spurred a consumer revolution that took hold of Paris in the late nineteenth century. This essay examines this culture of consumerism and the anxieties that came with it—in particular, anxieties about the effect that the market had on the moral standing of bourgeois women. Taking a multidisciplinary approach, this issue is discussed in the context of two period works from separate fields, one, an advertisement for “L’Artisan Moderne,” created by Toulouse-Lautrec in 1894, and the other Emile Zola’s immensely popular novel of 1880, Nana. Through the lens of these two works we can see two different views of female consumers from a nineteenth-century standpoint. This essay then draws on the work of present-day historians to explore changes in the marketplace that occurred during this period, including new methods of advertising and the development of department stores, as well as accounts of how men viewed women in the context of these changes and speculations as to why women behaved the way they did during this period. Examples from Nana and the “L’Artisan Moderne” poster are integrated to illustrate and reinforce these points

Assessment of a Driver Interface for Lateral Drift and Curve Speed Warning Systems: Mixed Results for Auditory and Haptic Warnings

Lateral Drift Warning (LDW) and Curve Speed Warning (CSW)systems were developed to address two main critical events in run-off-roadcrashes, which are road edge departure and excessive speed. The LDW systemused a two-stage alert system, with the first stage activating when the driverdeparted a lane with a dashed boundary and the imminent, or second stage, whendeparting a lane with a solid boundary. The CSW also employed a two-stage alert,with the level based on the degree of over-speed for the upcoming curve. Thehaptic modality, in the form of seat vibration, was chosen as the first levelwarning for both systems, and auditory was chosen as the second or most urgentlevel. The two systems were installed in a fleet of instrumented vehicles andloaned to 78 randomly selected licensed drivers for approximately 4 weeks.Debriefing questions detailing the driver’s experience with the system wereadministered and analyzed in a two by two design of modality by system. Afterexamination of both the statistical results and the open-ended comments, thequestion of which modality is most appropriate is still uncertain. Each modalityhad positive aspects. Haptic does not alert the entire car and participants alsoconsidered it less distracting. Auditory provided better recognition betweenwarnings and participants were better able to understand the meaning and therequired response for each warning

Field Test Results of a Road Departure Crash Warning System: Driver Acceptance, Perceived Utility and Willingness to Purchase

The road departure crash warning system field operational test (RDCW FOT) was conducted to assess the safety impacts, driver acceptance levels, and the maturity of road departure crash warning systems as installed on a light vehicle platform. This paper presents the results on driver acceptance and perceived utility of a road departure crash warning system

Theory of structural response to macroscopic electric fields in ferroelectric systems

We have developed and implemented a formalism for computing the structural response of a periodic insulating system to a homogeneous static electric field within density-functional perturbation theory (DFPT). We consider the thermodynamic potentials E(R,eta,e) and F(R,eta,e) whose minimization with respect to the internal structural parameters R and unit cell strain eta yields the equilibrium structure at fixed electric field e and polarization P, respectively. First-order expansion of E(R,eta,e) in e leads to a useful approximation in which R(P) and eta(P) can be obtained by simply minimizing the zero-field internal energy with respect to structural coordinates subject to the constraint of a fixed spontaneous polarization P. To facilitate this minimization, we formulate a modified DFPT scheme such that the computed derivatives of the polarization are consistent with the discretized form of the Berry-phase expression. We then describe the application of this approach to several problems associated with bulk and short-period superlattice structures of ferroelectric materials such as BaTiO3 and PbTiO3. These include the effects of compositionally broken inversion symmetry, the equilibrium structure for high values of polarization, field-induced structural phase transitions, and the lattice contributions to the linear and the non-linear dielectric constants.Comment: 19 pages, with 15 postscript figures embedded. Uses REVTEX4 and epsf macros. Also available at http://www.physics.rutgers.edu/~dhv/preprints/sai_pol/index.htm

Tunability of the dielectric response of epitaxially strained SrTiO3 from first principles

The effect of in-plane strain on the nonlinear dielectric properties of SrTiO3 epitaxial thin films is calculated using density-functional theory within the local-density approximation. Motivated by recent experiments, the structure, zone-center phonons, and dielectric properties with and without an external electric field are evaluated for several misfit strains within +-3% of the calculated cubic lattice parameter. In these calculations, the in-plane lattice parameters are fixed, and all remaining structural parameters are permitted to relax. The presence of an external bias is treated approximately by applying a force to each ion proportional to the electric field. After obtaining zero-field ground state structures for various strains, the zone-center phonon frequencies and Born effective charges are computed, yielding the zero-field dielectric response. The dielectric response at finite electric field bias is obtained by computing the field dependence of the structure and polarization using an approximate technique. The results are compared with recent experiments and a previous phenomenological theory. The tunability is found to be strongly dependent on the in-plane lattice parameter, showing markedly different behavior for tensile and compressive strains. Our results are expected to be of use for isolating the role of strain in the tunability of real ultrathin epitaxial films.Comment: 11 pages, with postscript figures embedded. Uses REVTEX and epsf macros. Also available at http://www.physics.rutgers.edu/~dhv/preprints/ant_srti/index.htm

A quantification of the relationship between neuronal responses in the rat rostral ventromedial medulla and noxious stimulation-evoked withdrawal reflexes

The rostral ventromedial medulla (RVM) regulates a range of involuntary behaviours but is most often associated with nociception via the action of pronociceptive ON cells and antinociceptive OFF cells. The phasic responses of ON and OFF cells determine whether or not incoming noxious signals provoke a withdrawal reflex, and previous studies have suggested that reflex RVM activity patterns actively shape motor output. Here we challenged the model by using juvenile rats, which are known to exhibit markedly different reflex responses compared with adults. By recording single-cell activity in the RVM and the electromyography responses of hindlimb flexor muscles to noxious thermal stimulation we found that the juvenile reflex had a shorter onset latency, was larger in amplitude and exhibited a decreased rise time compared with the adult reflex. The responses of ON and OFF cells faithfully tracked the shorter onset latency of the reflex by also responding earlier and, thus, still preceded the reflex. However, neither the reflex amplitude nor the ongoing response profile was predicted by the firing rate of RVM cells in either age group. Instead we found a close correspondence between RVM activity and the reflex only during the initiation of the response. Furthermore, the short rise time of the juvenile reflex was reflected in higher rates of change of both ON and OFF cell firing. Our data suggest that the RVM is associated only with the initiation of reflexes and does not shape ongoing muscle activity, which is more likely to be subserved by downstream spinal processes

Monte Carlo Study of Relaxor Systems: A Minimum Model for Pb(In1/2_{1/2}Nb1/2_{1/2})O3_3}

We examine a simple model for Pb(In$_{1/2}$Nb$_{1/2}$)O$_3$ (PIN), which includes both long-range dipole-dipole interaction and random local anisotropy. A improved algorithm optimized for long-range interaction has been applied for efficient large-scale Monte Carlo simulation. We demonstrate that the phase diagram of PIN is qualitatively reproduced by this minimum model. Some properties characteristic of relaxors such as nano-scale domain formation, slow dynamics and dispersive dielectric responses are also examined.Comment: 5 pages, 4 figure

Ab-initio design of perovskite alloys with predetermined properties: The case of Pb(Sc_{0.5} Nb_{0.5})O_{3}

A first-principles derived approach is combined with the inverse Monte Carlo technique to determine the atomic orderings leading to prefixed properties in Pb(Sc_{0.5}Nb_{0.5})O_{3} perovskite alloy. We find that some arrangements between Sc and Nb atoms result in drastic changes with respect to the disordered material, including ground states of new symmetries, large enhancement of electromechanical responses, and considerable shift of the Curie temperature. We discuss the microscopic mechanisms responsible for these unusual effects.Comment: 5 pages with 2 postscript figures embedde

The transcriptional landscape of endogenous retroelements delineates esophageal adenocarcinoma subtypes

Most cancer types exhibit aberrant transcriptional activity, including derepression of retrotransposable elements (RTEs). However, the degree, specificity and potential consequences of RTE transcriptional activation may differ substantially among cancer types and subtypes. Representing one extreme of the spectrum, we characterize the transcriptional activity of RTEs in cohorts of esophageal adenocarcinoma (EAC) and its precursor Barrett's esophagus (BE) from the OCCAMS (Oesophageal Cancer Clinical and Molecular Stratification) consortium, and from TCGA (The Cancer Genome Atlas). We found exceptionally high RTE inclusion in the EAC transcriptome, driven primarily by transcription of genes incorporating intronic or adjacent RTEs, rather than by autonomous RTE transcription. Nevertheless, numerous chimeric transcripts straddling RTEs and genes, and transcripts from stand-alone RTEs, particularly KLF5- and SOX9-controlled HERVH proviruses, were overexpressed specifically in EAC. Notably, incomplete mRNA splicing and EAC-characteristic intronic RTE inclusion was mirrored by relative loss of the respective fully-spliced, functional mRNA isoforms, consistent with compromised cellular fitness. Defective RNA splicing was linked with strong transcriptional activation of a HERVH provirus on Chr Xp22.32 and defined EAC subtypes with distinct molecular features and prognosis. Our study defines distinguishable RTE transcriptional profiles of EAC, reflecting distinct underlying processes and prognosis, thus providing a framework for targeted studies.</p