6,068 research outputs found
Towards Informative Statistical Flow Inversion
This is the accepted version of 'Towards Informative Statistical Flow Inversion', archived originally at arXiv:0705.1939v1 [cs.NI] 14 May 2007.A problem which has recently attracted research attention is that of estimating the distribution of flow sizes in internet traffic. On high traffic links it is sometimes impossible to record every packet. Researchers have approached the problem of estimating flow lengths from sampled packet data in two separate ways. Firstly, different sampling methodologies can be tried to more accurately measure the desired system parameters. One such method is the sample-and-hold method where, if a packet is sampled, all subsequent packets in that flow are sampled. Secondly, statistical methods can be used to ``invert'' the sampled data and produce an estimate of flow lengths from a sample. In this paper we propose, implement and test two variants on the sample-and-hold method. In addition we show how the sample-and-hold method can be inverted to get an estimation of the genuine distribution of flow sizes. Experiments are carried out on real network traces to compare standard packet sampling with three variants of sample-and-hold. The methods are compared for their ability to reconstruct the genuine distribution of flow sizes in the traffic
Particle-stabilized oscillating diver: a self-assembled responsive capsule
We report the experimental discovery of a self-assembled capsule, with
density set by interfacial glass beads and an internal bubble, that
automatically performs regular oscillations up and down a vial in response to a
temperature gradient. Similar composites featuring interfacial particles and
multiple internal compartments could be the solution to a variety of
application challenges.Comment: 7 pages, 3 figure
Native Spanish Speaker Intuition in Noun Gender Assignment
When an English word is borrowed into Spanish it has no specific gender and in order for the word to be used in the language it must be assigned a gender, either masculine or feminine. There are many different factors that may play a role in the assignment of gender to new English-origin words. This paper concentrates on English word final phonemes that do not correspond with the phonemes usually found in word final position in Spanish. For this study, words that are phonotactically possible in English but do not, in fact, exist were given to native Spanish speakers. The native Spanish speakers were then asked to assign the new words a gender. The words used in the study were designed to appear to be one gender according to their terminal phoneme. (ie. words ending in /o/ are generally masculine and words ending in /a/ are feminine) The definitions given to the words were designed to contradict the predictable gender associated with the terminal phoneme. In 90% of the cases the participants overlooked the definition and assigned the word to the gender associated with the terminal phoneme. This indicates that the meaning of the word and its function does not directly influence gender assignment. This study does indicate that the single most important factor in assigning gender to words borrowed from English into Spanish is the terminal phoneme
Practical Forecasting of AC Losses in Multi-layer 2G-HTS Cold Dielectric Conductors
With the recent progresses on the designing and manufacturing of lightweight
and high engineering current density superconducting cables, the need for an
established, fast, and sufficiently accurate computational model for the
forecasting of AC-losses in cold-dielectric conductors, is pivotal for
increasing the investment confidence of power grid operators. However,
validating such models is not an easy task, this because on the one hand, there
is a low availability of experimental results for large scale power cables and,
on the other hand, there is a large number of 2G-HTS tapes involved whose
cross-sectional aspect ratio hinders the numerical convergence of the models
within reasonable delivery times. Thus, aiming to overcome this challenge, we
present a detailed two-dimensional H-model capable to reproduce the
experimentally measured AC-losses of multi-layer power cables made of tens of
2G-HTS tapes. Two cable designs with very high critical currents have been
considered, the first rated at 1.7 kA critical current, consisting of fifty 4
mm width 2G-HTS tapes, these split in 5 concentric layers wound over a
cylindrical former, with the three inner layers forming an arrangement of 24
tapes shielded by two further layers with 13 tapes each. This cable is
contrasted with a size wise equivalent cable with 67 superconducting tapes
rated at 3.2 kA critical current, whose design implies the use of 40 tapes of 3
mm width split within four core layers, and 27 tapes of 4 mm width distributed
in two shielding layers. In both situations a remarkable resemblance between
the simulations and experiments has been found, rendering to acceptable
estimates of the AC-losses for cold dielectric conductors, and offering a
unique view of the local electrodynamics of the wound tapes where the
mechanisms of shielding, magnetization, and transport currents can coexist
within the hysteretic process.Comment: 4 Figures, 6 page
Emotions and identity work: Emotions as discursive resources in the constitution of junior professionals’ identities
© The Author(s) 2018. For junior professionals, notions of professional identity established during their education are often called into question in the early stages of their professional careers. The workplace gives rise to identity challenges that manifest in significant emotional struggles. However, although extant literature highlights how emotions trigger and accompany identity work, the constitutive role of emotions in identity work is under-researched. In this article, we analyse how junior professionals mobilize emotions as discursive resources for identity work. Drawing on an empirical study of junior architects employed in professional service firms, we examine how professional identities, imbued with varying forms of discipline and agency, are discursively represented. The study makes two contributions to the literature on emotions and identity work. First, we identify three key identity work strategies (idealizing, reframing and distancing) that are bound up in junior architects’ emotion talk. We suggest that these strategies act simultaneously as a coping mechanism and as a disciplinary force in junior architects’ efforts to constitute themselves as professionals. Second, we argue that identity work may not always lead to the accomplishment of a positive sense of self but can express a sense of disillusionment that leads to the constitution of dejected professional identities
Simplification of networks by conserving path diversity and minimisation of the search information.
Alternative paths in a network play an important role in its functionality as they can maintain the information flow under node/link failures. In this paper we explore the navigation of a network taking into account the alternative paths and in particular how can we describe this navigation in a concise way. Our approach is to simplify the network by aggregating into groups the nodes that do not contribute to alternative paths. We refer to these groups as super-nodes, and describe the post-aggregation network with super-nodes as the skeleton network. We present a method to describe with the least amount of information the paths in the super-nodes and skeleton network. Applying our method to several real networks we observed that there is scaling behaviour between the information required to describe all the paths in a network and the minimal information to describe the paths of its skeleton. We show how from this scaling we can evaluate the information of the paths for large networks with less computational cost
Infrared astronomical satellite (IRAS) catalogs and atlases. Volume 1: Explanatory supplement
The Infrared Astronomical Satellite (IRAS) was launched on January 26, 1983. During its 300-day mission, IRAS surveyed over 96 pct of the celestial sphere at four infrared wavelengths, centered approximately at 12, 25, 60, and 100 microns. Volume 1 describes the instrument, the mission, and data reduction
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Medium-chain triglycerides and conjugated linoleic acids in beverage form increase satiety and reduce food intake in humans
Both developed and developing countries are seeing increasing trends of obesity in people young and old. It is thought that satiety may play a role in the prevention of obesity by increasing satiety and reducing energy intake. We hypothesized that medium-chain triglycerides (MCT) would increase satiety and decrease food intake compared with conjugated linoleic acid (CLA) and a control oil. Nineteen healthy participants were tested on 3 separate occasions, where they consumed a beverage test breakfast containing (1) vegetable oil (control), (2) CLA, or (3) MCT. Participants self-requested an ad libitum sandwich buffet lunch. Time between meals, satiety from visual analog scales, energy intake at lunch, and intake for the rest of the day using weighed food diaries were measured. The results indicated that the time until a meal request was significantly different between the 3 meals (P=.016); however, there were no differences in intakes at the ad libitum lunch (P>.05). The CLA breakfast generated the greatest delay in meal time request. There was a difference between the control lipid compared with both the CLA and MCT for energy intake over the remainder of the test day and for total energy intake on the test day (P.05). Both CLA and MCT increased satiety and reduced energy intake, indicating a potential role in aiding the maintenance of energy balance
Demixing, remixing and cellular networks in binary liquids containing colloidal particles
We present a confocal-microscopy study of demixing and remixing in binary
liquids containing colloidal particles. First, particle-stabilized emulsions
have been fabricated by nucleation and growth of droplets upon cooling from the
single-fluid phase. We show that their stability mainly derives from
interfacial particles; the surplus of colloids in the continuous phase possibly
provides additional stability. Upon heating these emulsions, we have observed
the formation of polyhedral cellular networks of colloids, just before the
system remixes. Given a suitable liquid-liquid composition, the initial
emulsions cross the binary-liquid symmetry line due to creaming. Therefore,
upon heating, the droplets do not shrink and they remain closely packed. The
subsequent network formation relies on a delicate balance between the Laplace
pressure and the pressure due to creaming/remixing. As high concentrations of
colloids in the cell walls inhibit film thinning and rupture, the networks can
be stabilized for more than 30 minutes. This opens up an avenue for their
application in the fabrication of advanced materials.Comment: http://dx.doi.org/10.1039/b918002
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