Online Station Assignment for Electric Vehicle Battery Swapping

This paper investigates the online station assignment for (commercial) electric vehicles (EVs) that request battery swapping from a central operator, i.e., in the absence of future information a battery swapping service station has to be assigned instantly to each EV upon its request. Based on EVs' locations, the availability of fully-charged batteries at service stations in the system, as well as traffic conditions, the assignment aims to minimize cost to EVs and congestion at service stations. Inspired by a polynomial-time offline solution via a bipartite matching approach, we develop an efficient and implementable online station assignment algorithm that provably achieves the tight (optimal) competitive ratio under mild conditions. Monte Carlo experiments on a real transportation network by Baidu Maps show that our algorithm performs reasonably well on realistic inputs, even with a certain amount of estimation error in parameters

Online Station Assignment for Electric Vehicle Battery Swapping

This paper investigates the online station assignment for (commercial) electric vehicles (EVs) that request battery swapping from a central operator, i.e., in the absence of future information a battery swapping service station has to be assigned instantly to each EV upon its request. Based on EVs' locations, the availability of fully-charged batteries at service stations in the system, as well as traffic conditions, the assignment aims to minimize cost to EVs and congestion at service stations. Inspired by a polynomial-time offline solution via a bipartite matching approach, we develop an efficient and implementable online station assignment algorithm that provably achieves the tight (optimal) competitive ratio under mild conditions. Monte Carlo experiments on a real transportation network by Baidu Maps show that our algorithm performs reasonably well on realistic inputs, even with a certain amount of estimation error in parameters

On the Implementation of OPF-Based Setpoints for Active Distribution Networks

In the context of active distribution networks, AC Optimal Power Flow (OPF) has shown great potential to calcu-late setpoints for controllable devices. Although considerable literature exists, temporal aspects that may affect the actual exe-cution of these setpoints are rarely investigated. Due to the di-verse operating characteristics of controllable devices (i.e., de-lays, ramp rates and deadbands), when these setpoints are exe-cuted by multiple devices without adequate considerations, the resulting outcome can differ drastically from what is expected; leading to violations of network constraints and excessive control actions. Therefore, this work proposes a series of necessary adap-tations within the controllers of existing devices as well as in the OPF formulation to cater for the diversity in operating charac-teristics, ensuring that calculated setpoints are adequately im-plemented by controllable devices. This involves the direct con-trol of conventional devices and enforcing a new ramping behav-ior for inverter-interfaced devices. Furthermore, a linear, mixed-integer formulation is proposed to handle discrete devices and improve scalability in large networks. Co-simulation results (us-ing a UK test network with the objective of maximizing renewa-ble energy production and considering 1s time-step) demonstrate that, by catering for the operating characteristics of controllable devices, the expected outcome from OPF-based setpoints can be achieved

Translating education neuroscience for teachers

Translating Neuroscience to education involves providing accurate and simplified information about neuroscience to teachers. The aim of this research was to understand if providing translated abstracts from neuroscientific articles helped teachers understand content more thoroughly. Surveys, experimental manipulation, and focus group discussions were conducted with thirty teachers from two primary schools in Singapore. Teachers shared their familiarity with neuroscience, self-rated their understanding of neuroscientific abstracts, and provided feedback on the abstracts’ translations. Results indicate that translated abstracts did not improve attitudes significantly; however, focus group discussions revealed that teachers were more interested in the applications of neuroscience research in classroom pedagogy. These findings highlight the importance of improving communication between neuroscientists and educators

World-line Quantisation of a Reciprocally Invariant System

We present the world-line quantisation of a system invariant under the symmetries of reciprocal relativity (pseudo-unitary transformations on ``phase space coordinates" $(x^\mu(\tau),p^\mu(\tau))$ which preserve the Minkowski metric and the symplectic form, and global shifts in these coordinates, together with coordinate dependent transformations of an additional compact phase coordinate, $\theta(\tau)$). The action is that of free motion over the corresponding Weyl-Heisenberg group. Imposition of the first class constraint, the generator of local time reparametrisations, on physical states enforces identification of the world-line cosmological constant with a fixed value of the quadratic Casimir of the quaplectic symmetry group $Q(D-1,1)\cong U(D-1,1)\ltimes H(D)$, the semi-direct product of the pseudo-unitary group with the Weyl-Heisenberg group (the central extension of the global translation group, with central extension associated to the phase variable $\theta(\tau)$). The spacetime spectrum of physical states is identified. Even though for an appropriate range of values the restriction enforced by the cosmological constant projects out negative norm states from the physical spectrum, leaving over spin zero states only, the mass-squared spectrum is continuous over the entire real line and thus includes a tachyonic branch as well

NICMOS Imaging of the Nuclei of Arp 220

We report high resolution imaging of the ultraluminous infrared galaxy Arp 220 at 1.1, 1.6, and 2.22 microns with NICMOS on the HST. The diffraction-limited images at 0.1--0.2 arcsecond resolution clearly resolve both nuclei of the merging galaxy system and reveal for the first time a number of luminous star clusters in the circumnuclear envelope. The morphologies of both nuclei are strongly affected by dust obscuration, even at 2.2 microns : the primary nucleus (west) presents a crescent shape, concave to the south and the secondary (eastern) nucleus is bifurcated by a dust lane with the southern component being very reddened. In the western nucleus, the morphology of the 2.2 micron emission is most likely the result of obscuration by an opaque disk embedded within the nuclear star cluster. The morphology of the central starburst-cluster in the western nucleus is consistent with either a circumnuclear ring of star formation or a spherical cluster with the bottom half obscured by the embedded dust disk. Comparison of cm-wave radio continuum maps with the near-infrared images suggests that the radio nuclei lie in the dust disk on the west and near the highly reddened southern component of the eastern complex. The radio nuclei are separated by 0.98 arcseconds (corresponding to 364 pc at 77 Mpc) and the half-widths of the infrared nuclei are approximately 0.2-0.5 arcseconds. At least 8, unresolved infrared sources -- probably globular clusters -- are also seen in the circumnuclear envelope at radii 2-7 arcseconds . Their near-infrared colors do not significantly constrain their ages.Comment: LaTex, 15 pages with 1 gif figure and 5 postscript figures. ApJL accepte

Mid-infrared plasmons in scaled graphene nanostructures

Plasmonics takes advantage of the collective response of electrons to electromagnetic waves, enabling dramatic scaling of optical devices beyond the diffraction limit. Here, we demonstrate the mid-infrared (4 to 15 microns) plasmons in deeply scaled graphene nanostructures down to 50 nm, more than 100 times smaller than the on-resonance light wavelength in free space. We reveal, for the first time, the crucial damping channels of graphene plasmons via its intrinsic optical phonons and scattering from the edges. A plasmon lifetime of 20 femto-seconds and smaller is observed, when damping through the emission of an optical phonon is allowed. Furthermore, the surface polar phonons in SiO2 substrate underneath the graphene nanostructures lead to a significantly modified plasmon dispersion and damping, in contrast to a non-polar diamond-like-carbon (DLC) substrate. Much reduced damping is realized when the plasmon resonance frequencies are close to the polar phonon frequencies. Our study paves the way for applications of graphene in plasmonic waveguides, modulators and detectors in an unprecedentedly broad wavelength range from sub-terahertz to mid-infrared.Comment: submitte

Active and passive aperture coupled microstrip antenna design

Microstrip antennas has a few feeding technique applicable to them. One of them is the non-contacting feeds, which is the aperture-coupled feed techniques. The main mechanism of power transfer between its feed line and patch is the coupling mechanism through the aperture. This work is an effort to design, simulate, fabricate and measurement of passive and active rectangular patch with aperture coupled feed techniques. Simulation is being done using the Method of Moments (MoM). This is simulated in Microwave Office software. This design intends to focus on studying the differences in simulated and measured parameters of the antenna on its return loss, bandwidth and radiation pattern

The Sydney Multisite Intervention of LaughterBosses and ElderClowns (SMILE) study: Cluster randomised trial of humour therapy in nursing homes

Objectives: To determine whether humour therapy reduces depression (primary outcome), agitation and behavioural disturbances and improves social engagement and quality-of-life in nursing home residents. Design: The Sydney Multisite Intervention of LaughterBosses and ElderClowns study was a singleblind cluster randomised controlled trial of humour therapy. Setting: 35 Sydney nursing homes. Participants: All eligible residents within geographically defined areas within each nursing home were invited to participate. Intervention: Professional 'ElderClowns' provided 9-12 weekly humour therapy sessions, augmented by resident engagement by trained staff 'LaughterBosses'. Controls received usual care. Measurements: Depression scores on the Cornell Scale for Depression in Dementia, agitation scores on the Cohen-Mansfield Agitation Inventory, behavioural disturbance scores on the Neuropsychiatric Inventory, social engagement scores on the withdrawal subscale of Multidimensional Observation Scale for Elderly Subjects, and self-rated and proxy-rated quality-of-life scores on a health-related quality-of-life tool for dementia, the DEMQOL. All outcomes were measured at the participant level by researchers blind to group assignment. Randomisation: Sites were stratified by size and level of care then assigned to group using a random number generator. Results: Seventeen nursing homes (189 residents) received the intervention and 18 homes (209 residents) received usual care. Groups did not differ significantly over time on the primary outcome of depression, or on behavioural disturbances other than agitation, social engagement and quality of life. The secondary outcome of agitation was significantly reduced in the intervention group compared with controls over 26 weeks (time by group interaction adjusted for covariates: p=0.011). The mean difference in change from baseline to 26 weeks in Blom-transformed agitation scores after adjustment for covariates was 0.17 (95% CI 0.004 to 0.34, p=0.045). Conclusions: Humour therapy did not significantly reduce depression but significantly reduced agitation

Svestka's Research: Then and Now

Zdenek Svestka's research work influenced many fields of solar physics, especially in the area of flare research. In this article I take five of the areas that particularly interested him and assess them in a "then and now" style. His insights in each case were quite sound, although of course in the modern era we have learned things that he could not readily have envisioned. His own views about his research life have been published recently in this journal, to which he contributed so much, and his memoir contains much additional scientific and personal information (Svestka, 2010).Comment: Invited review for "Solar and Stellar Flares," a conference in honour of Prof. Zden\v{e}k \v{S}vestka, Prague, June 23-27, 2014. This is a contribution to a Topical Issue in Solar Physics, based on the presentations at this meeting (Editors Lyndsay Fletcher and Petr Heinzel