31,583 research outputs found
Переклад у галузі електроенергетики. Методичні рекомендації до практичних занять з дисципліни для студентів спеціальності 7.030507 «Переклад» напряму підготовки 035 «Філологія»
Методичні матеріали призначено для самостійної роботи студентів
спеціальності 7.030507 “Переклад” напряму підготовки 035 «Філологія» для
організації практичних занять із дисципліни «Переклад у галузі електроенергетики».
Рекомендації орієнтовано на вдосконалення навичок перекладу науково-технічних текстів
Last Minute Feedback
Feedback mechanisms that allow partners to rate each other after a transaction are considered crucial for the success of anonymous internet trading platforms. We document an asymmetry in the feedback behavior on eBay, propose an explanation based on the micro structure of the feedback mechanism and the time when feedbacks are given, and support this explanation by findings from a large data set. Our analysis implies that the informational content of feedback records is likely to be low. The reason for this is that agents appear to leave feedbacks strategically. Negative feedbacks are given late, in the "last minute," or not given at all, most likely because of the fear of retaliative negative feedback. Conversely, positive feedbacks are given early in order to encourage reciprocation. Towards refining our insights into the observed pattern, we look separately at buyers and sellers, and relate the magnitude of the effects to the trading partners' experience
Ownership and control in a competitive industry
We study a differentiated product market in which an investor initially owns a controlling stake in one of two competing firms and may acquire a non-controlling or a controlling stake in a competitor, either directly using her own assets, or indirectly via the controlled firm. While industry profits are maximized within a symmetric two product monopoly, the investor attains this only in exceptional cases. Instead, she sometimes acquires a noncontrolling stake. Or she invests asymmetrically rather than pursuing a full takeover if she acquires a controlling one. Generally, she invests indirectly if she only wants to affect the product market outcome, and directly if acquiring shares is profitable per se. --differentiated products,separation of ownership and control,private benefits of control
Comparison of primordial tensor power spectra from the deformed algebra and dressed metric approaches in loop quantum cosmology
Loop quantum cosmology tries to capture the main ideas of loop quantum
gravity and to apply them to the Universe as a whole. Two main approaches
within this framework have been considered to date for the study of
cosmological perturbations: the dressed metric approach and the deformed
algebra approach. They both have advantages and drawbacks. In this article, we
accurately compare their predictions. In particular, we compute the associated
primordial tensor power spectra. We show -- numerically and analytically --
that the large scale behavior is similar for both approaches and compatible
with the usual prediction of general relativity. The small scale behavior is,
the other way round, drastically different. Most importantly, we show that in a
range of wavenumbers explicitly calculated, both approaches do agree on
predictions that, in addition, differ from standard general relativity and do
not depend on unknown parameters. These features of the power spectrum at
intermediate scales might constitute a universal loop quantum cosmology
prediction that can hopefully lead to observational tests and constraints. We
also present a complete analytical study of the background evolution for the
bouncing universe that can be used for other purposes.Comment: 15 pages, 7 figure
The Actual Structure of eBay’s Feedback Mechanism and Early Evidence on the Effects of Recent Changes
eBay’s feedback mechanism is considered crucial to establishing and maintaining trust on the world’s largest trading platform. The effects of a user’s reputation on the probability of sale and on prices are at the center of a large number of studies. More recent theoretical work considers aspects of the mechanism itself. Yet, there is confusion amongst users about its exact institutional details, which also changed substantially in the last few months. An understanding of these details, and how the mechanism is perceived by users, is crucial for any assessment of the system. We provide a thorough description of the institutional setup of eBay’s feedback mechanism, including recent changes to it. Most importantly, buyers now have the possibility to leave additional, anonymous ratings on sellers on four different criteria. We discuss the implications of these changes and provide first descriptive evidence on their impact on rating behavior
Constructing families of moderate-rank elliptic curves over number fields
We generalize a construction of families of moderate rank elliptic curves
over to number fields . The construction, originally
due to Steven J. Miller, \'Alvaro Lozano-Robledo and Scott Arms, invokes a
theorem of Rosen and Silverman to show that computing the rank of these curves
can be done by controlling the average of the traces of Frobenius, the
construction for number fields proceeds in essentially the same way. One
novelty of this method is that we can construct families of moderate rank
without having to explicitly determine points and calculating determinants of
height matrices.Comment: Version 1.0, 4 pages, sequel to arXiv:math/040657
Dust Formation and He II 4686 emission in the Dense Shell of the Peculiar Type Ib Supernova 2006jc
We present evidence for the formation of dust grains in an unusual Type Ib SN
based on late-time spectra of SN 2006jc. The progenitor suffered an LBV-like
outburst just 2 yr earlier, and we propose that the dust formation is a
consequence of the SN blast wave overtaking that LBV-like shell. The key
evidence for dust formation is (a) the appearance of a red/near-IR continuum
source fit by 1600 K graphite grains, and (b) fading of the redshifted sides of
He I emission lines, yielding progressively more asymmetric blueshifted lines
as dust obscures receding material. This provides the strongest case yet for
dust formation in any SN Ib/c. Both developments occurred between 51 and 75 d
after peak, while other SNe observed to form dust did so after a few hundred
days. Geometric considerations indicate that dust formed in the dense swept-up
shell between the forward and reverse shocks, and not in the freely expanding
SN ejecta. Rapid cooling leading to dust formation may have been aided by
extremely high shell densities, as indicated by He I line ratios. The brief
epoch of dust formation is accompanied by He II 4686 emission and enhanced
X-ray emission. These clues suggest that the unusual dust formation in this
object was not due to properties of the SN itself, but instead -- like most
peculiarities of SN 2006jc -- was a consequence of the dense environment
created by an LBV-like eruption 2 yr before the SN.Comment: ApJ, accepted. added some discussion and 2 figures, better title,
conclusions same as previous version. 12 pages, 4 color fig
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