cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Nonlinear Quantum Mechanics at the Planck Scale
Creators: name: Svetlichny, George
Publisher: name: arXiv
Year: 2004
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: I argue that the linearity of quantum mechanics is an emergent feature at the Planck scale, along with the manifold structure of space-time. In this regime the usual causality violation objections to nonlinearity do not apply, and nonlinear effects can be of comparable magnitude to the linear ones and still be highly suppressed at low energies. This can offer alternative approaches to quantum gravity and to the evolution of the early universe.
description: Talk given at the International Quantum Structures 2004 meeting, 16 pages LaTeX
On the Temperature Dependence of the Casimir Effect
Creators: name: Brevik, I.
name: Aarseth, J. B.
name: Høye, J. S.
name: Milton, K. A.
Publisher: name: arXiv
Year: 2004
Subjects: subject: Quantum Physics (quant-ph)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: The temperature dependence of the Casimir force between a real metallic plate and a metallic sphere is analyzed on the basis of optical data concerning the dispersion relation of metals such as gold and copper. Realistic permittivities imply, together with basic thermodynamic considerations, that the transverse electric zero mode does not contribute. This results in observable differences with the conventional prediction, which does not take this physical requirement into account. The results are shown to be consistent with the third law of thermodynamics, as well as being consistent with current experiments. However, the predicted temperature dependence should be detectable in future experiments. The inadequacies of approaches based on {\it ad hoc} assumptions, such as the plasma dispersion relation and the use of surface impedance without transverse momentum dependence, are discussed.
description: 14 pages, 3 eps figures, revtex4. New version includes clarifications and new reference. Accepted for publication in Phys. Rev. E
Gravitational-wave surrogate models powered by artificial neural networks: The ANN-Sur for waveform generation
Creators: name: Khan, Sebastian
name: Green, Rhys
Publisher: name: arXiv
Year: 2020
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: Inferring the properties of black holes and neutron stars is a key science goal of gravitational-wave (GW) astronomy. To extract as much information as possible from GW observations we must develop methods to reduce the cost of Bayesian inference. In this paper, we use artificial neural networks (ANNs) and the parallelisation power of graphics processing units (GPUs) to improve the surrogate modelling method, which can produce accelerated versions of existing models. As a first application of our method, ANN-Sur, we build a time-domain surrogate model of the spin-aligned binary black hole (BBH) waveform model SEOBNRv4. We achieve median mismatches of 2e-5 and mismatches no worse than 2e-3. For a typical BBH waveform generated from 12 Hz with a total mass of $60 M_\odot$ the original SEOBNRv4 model takes 1812 ms. Existing bespoke code optimisations (SEOBNRv4opt) reduced this to 91.6 ms and the interpolation based, frequency-domain surrogate SEOBNRv4ROM can generate this waveform in 6.9 ms. Our ANN-Sur model, when run on a CPU takes 2.7 ms and just 0.4 ms when run on a GPU. ANN-Sur can also generate large batches of waveforms simultaneously. We find that batches of up to 10^4 waveforms can be evaluated on a GPU in just 163 ms, corresponding to a time per waveform of 0.016 ms. This method is a promising way to utilise the parallelisation power of GPUs to drastically increase the computational efficiency of Bayesian parameter estimation.
Spatial and Momentum Imaging of the Pion and Kaon
Creators: name: Shi, Chao
name: Bednar, Kyle
name: Cloët, Ian C.
name: Freese, Adam
Publisher: name: arXiv
Year: 2020
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: We determine the leading Fock state light front wave functions (LFWFs) of the pion and kaon via light front projections of the covariant Bethe-Salpeter wave function. Using these LFWFs we study the multi-dimensional images of the valence quarks in the pion and kaon that are provided by their generalized parton distribution functions (GPDs) and transverse momentum dependent parton distribution functions (TMDs). Moments of the GPDs are taken to obtain the electromagnetic and gravitational form factors of the pion and kaon, and comparisons to available experimental and lattice data are made. Highlights from this study include predictions that the mean-squared impact parameter for the quarks in the pion and kaon are: $\langle \vec{b}_T^2\rangle_{u}^π=0.11$fm$^2$, $\langle \vec{b}_T^2\rangle_{s}^K=0.08$fm$^2$, and $\langle \vec{b}_T^2\rangle_{u}^K=0.13$fm$^2$, and therefore the $s$ quark in the kaon is much closer to the center of transverse momentum than the $u$ quark. From the electromagnetic and gravitational form factors we find that the light-cone energy radii are about 60\% smaller than the light-cone charge radii for each quark sector in the pion and kaon. A quantitative measure of the importance of the leading Fock state is obtained via comparison with a full DSE calculation (containing an infinite tower of Fock states) for the pion form factor.
2230: Albert James Sully
Creators: name: Project Team, Lest We Forget
Publisher: name: University of Oxford
Year: 2024
Subjects: classificationCode: 430304
subject: British history
classificationCode: 430308
subject: European history (excl. British, classical Greek and Roman)
classificationCode: 430316
subject: International history

description: A series of postcards form Albert Sully sent to his wife from the front. The collection also includes his signing up card. The post cards have simple tick boxes to tell the receiver how the sender is. There is no opportunity to say any more.
Ranking państw UE ze względu na potencjalne możliwości zaspokojenia zapotrzebowania na produkty rolnicze z wykorzystaniem metod porządkowania liniowego
Creators: name: Kisielińska, Joanna
name: Kisielińska, Joanna
Publisher: name: Unknown
Year: 2016
Subjects: subject: Agribusiness
subject: Agricultural and Food Policy
subject: Community/Rural/Urban Development
subject: Research Methods/ Statistical Methods
subject: agricultural potential
subject: methods of linear ordering
subject: potencjał rolnictwa
subject: metody porządkowania liniowego

description: The aim of the research presented in the article was to prepare, using the methods of linear ordering, the ranking of countries because of the potential to meet the demand for agricultural products. An additional aim, of a methodical, was to compare the two procedures, help in choosing the method of linear ordering. / Synopsis. Celem badań przedstawionych w artykule było sporządzenie, z wykorzystaniem metod porządkowania liniowego, rankingu państw ze względu na potencjalne możliwości zaspokojenia zapotrzebowania na produkty rolnicze. Celem dodatkowym, o charakterze metodyczny, było porównanie dwóch procedur wspomagających wybór metody porządkowania liniowego.
Noncommutative Decrumpling Inflation and Running of the Spectral Index
Creators: name: Nasseri, Forough
name: Alavi, S. A.
Publisher: name: arXiv
Year: 2004
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We present a new inflation model, known as noncommutative decrumpling inflation, in which space has noncommutative geometry with time variability of the number of spatial dimensions. Within the framework of noncommutative decrumpling inflation, we compute both the spectral index and its running. Our results show that the effects of both time variability of the number of spatial dimensions and noncommutative geometry on the spectral index and its running. Two classes of examples have been studied and comparisons made with the standard slow-roll formulae. We conclude that the effects of noncommutative geometry on the spectral index and its running are much smaller than the effects of time variability of spatial dimensions.
description: 15 pages, accepted for publication in Int.J.Mod.Phys.D
H0 tension or T0 tension?
Creators: name: Ivanov, Mikhail M.
name: Ali-Haïmoud, Yacine
name: Lesgourgues, Julien
Publisher: name: arXiv
Year: 2020
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We study if the discrepancy between the local and cosmological measurements of the Hubble constant $H_0$ can be reformulated as a tension in the cosmic microwave background (CMB) monopole temperature $T_0$. The latter is customarily fixed to the FIRAS best-fit value in CMB data analyses. Although this value was confirmed by several independent experiments, it is interesting to see how much parameter constraints depend on this prior. We first provide a detailed pedagogical description of the $T_0$ effects on cosmological observables. We show that the recombination history and transfer functions do not depend on $T_0$, provided they are parametrized by the energy scale rather than redshift, and at fixed dark matter and baryon densities per CMB photon. Thus, $T_0$ is only a property of the observer, quantifying the amount of expansion between key cosmological events and today. As a consequence, the sole effect of $T_0$ on small-scale primary CMB anisotropies is through the angular diameter distance to the epoch of last scattering, resulting in a near-perfect degeneracy between $T_0$ and $H_0$. This geometric degeneracy is partially lifted by the late-time integrated Sachs-Wolfe effect and CMB lensing. Still, Planck data alone is consistent with a broad region in the $H_0-T_0$ plane, implying that removing the FIRAS prior on $T_0$ can make Planck and SH0ES less discrepant, without introducing new physics beyond $Λ$CDM. One may break the degeneracy by combining Planck with SH0ES, yielding an independent measurement of $T_0$, which happens to be in $3σ$ tension with FIRAS. Therefore, the Hubble tension indeed can be recast into the $T_0$ tension. The agreement with FIRAS is restored when combining Planck with the baryon acoustic oscillation data instead of SH0ES. Thus, the tension between SH0ES and cosmological measurements of $H_0$ persists even if we discard the FIRAS $T_0$ prior.
description: v2: 22 pages, 8 figures, corrected a mistake due to calibration of temperature maps, qualitative results and conclusions unchanged
Integral Transforms and $\mathcal{PT}$-symmetric Hamiltonians
Creators: name: AlMasri, M. W.
name: Wahiddin, M. R. B.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Motivated by the fact that twice the Fourier transform plays the role of parity operator. We systematically study integral transforms in the case of $\mathcal{PT}$-symmetric Hamiltonian. First, we obtain a closed analytical formula for the exponential Fourier transform of a general $\mathcal{PT}$-symmetric Hamiltonian. Using the Segal-Bargmann transform, we investigate the effect of the Fourier transform on the eigenfunctions of the original Hamiltonian. As an immediate application, we comment on the holomorphic representation of non-Hermitian spin chains, in which the Hamiltonian operator is written in terms of analytical phase-space coordinates and their partial derivatives in the Bargmann space rather than matrices in the vector Hilbert space. Finally, we discuss the effect of integral transforms in the study of the Swanson Hamiltonian.
description: 19 pages, revised version
Supplementary Methods and Results from Physiological synchrony predicts observational threat learning in humans
Creators: name: Pärnamets, Philip
name: Espinosa, Lisa
name: Olsson, Andreas
Publisher: name: The Royal Society
Year: 2020
Subjects: subject: Neuroscience
subject: 170299 Cognitive Science not elsewhere classified
subject: FOS: Psychology
subject: 60801 Animal Behaviour
subject: FOS: Biological sciences

description: Understanding how information about threats in the environment is shared and transmitted between individuals is crucial for explaining adaptive, survival-related behaviour in humans and other animals, and for developing treatments for phobias and other anxiety disorders. Research across species has shown that observing a conspecific’, a ‘demonstrator’s, threat responses causes strong and persistent threat memories in the ‘observer’. Here, we examined if physiological synchrony between demonstrator and observer can serve to predict the strength of observationally acquired conditioned responses. We measured synchrony between demonstrators’ and observers’ phasic electrodermal signals during learning, which directly reflects autonomic nervous system activity. Prior interpersonal synchrony predicted the strength of the observer’s later skin conductance responses to threat predicting stimuli, in the absence of the demonstrator. Dynamic coupling between an observer’s and a demonstrator’s autonomic nervous system activity may reflect experience sharing processes facilitating the formation of observational threat associations.
Genomic convergence towards diploidy in Saccharomyces cerevisiae : patterns and mechanisms
Creators: name: Gerstein, Aleeza Cara
Publisher: name: University of British Columbia
Year: 2010

description: Genome size, a fundamental aspect of any organism, is subject to a variety of mutational and selection pressures. We investigated genome size evolution in haploid, diploid, and tetraploid isogenic lines of the yeast Saccharomyces cerevisiae. Over the course of ~1800 generations of mitotic division, we observed convergence towards diploid DNA content in all replicate lines. Comparative genomic hybridization with microarrays revealed nearly euploid DNA content by the end of the experiment. As the vegetative life cycle of Saccharomyces cerevisiae is predominantly diploid, this experiment provides evidence that genome size evolution is constrained, with selection favouring the genomic content typical of the yeast’s evolutionary past. It is not surprising to us that mutants diploids would be able to out-compete tetraploid individuals; diploid growth rates are significantly higher than tetraploids (data not shown) and it is known that tetraploid individuals are quite ’sick’. To determine the selective benefit that would allow mutant diploids to out-compete haploids, we measured a number of fitness and cell size parameters. Neither growth rate nor biomass production differed between ploidy levels. At the phenotypic level we found that cell size increased dramatically over the 1800 generations of evolution. We are thus left with the hypothesis that batch culture evolution selects on larger cell size, and that diploids, which are larger than haploids, have an advantage. To investigate further the mechanism that allows tetraploid individuals to lose two entire sets of chromosomes, a second batch culture experiment was conducted starting with triploid-sized individuals. This experiment demonstrated that a transition toward diploid genomic content was indeed possible for triploids. This result suggests that a chromosome distributive system may be present in Saccharomyces cerevisiae that allows chromosomes to be properly segregated (i.e., in euploid or near euploid sets) to daughter cells through a mitotic process. Selection on genome size remains poorly understood. This thesis provides evidence that historical size may act as a constraint, and that multiple mechanisms are at play to allow haploids and tetraploids to rapidly change genome size towards diploidy, the historical ploidy of Saccharomyces cerevisiae.
Models with Recoil for Bose-Einstein Condensation and Superradiance
Creators: name: Pulé, Joseph V.
name: Verbeure, André F.
name: Zagrebnov, Valentin A.
Publisher: name: arXiv
Year: 2004
Subjects: subject: Mathematical Physics (math-ph)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: In this paper we consider two models which exhibit equilibrium BEC superradiance. They are related to two different types of superradiant scattering observed in recent experiments. The first one corresponds to the amplification of matter-waves due to Raman superradiant scattering from a cigar-shaped BE condensate, when the recoiled and the condensed atoms are in different internal states. The main mechanism is stimulated Raman scattering in two-level atoms, which occurs in a superradiant way. Our second model is related to the superradiant Rayleigh scattering from a cigar-shaped BE condensate. This again leads to a matter-waves amplification but now with the recoiled atoms in the same state as the atoms in the condensate. Here the recoiling atoms are able to interfere with the condensate at rest to form a matter-wave grating (interference fringes) which is observed experimentally.
Supplementary material from Coordinated changes across the O2 transport pathway underlie adaptive increases in thermogenic capacity in high-altitude deer mice
Creators: name: Tate, Kevin B.
name: Wearing, Oliver H.
name: Ivy, Catherine M.
name: Cheviron, Zachary A.
name: Storz, Jay F.
name: McClelland, Grant B.
name: Scott, Graham R.
Publisher: name: The Royal Society
Year: 2020
Subjects: subject: Physiology
subject: FOS: Biological sciences
subject: Evolutionary Biology

description: Animals native to the hypoxic and cold environment at high altitude provide an excellent opportunity to elucidate the integrative mechanisms underlying the adaptive evolution and plasticity of complex traits. The capacity for aerobic thermogenesis can be a critical determinant of survival for small mammals at high altitude, but the physiological mechanisms underlying the evolution of this performance trait remain unresolved. We examined this issue by comparing high-altitude deer mice (Peromyscus maniculatus) to low-altitude deer mice and white-footed mice (P. leucopus). Mice were bred in captivity and adults were acclimated to each of four treatments: warm (25°C) normoxia, warm hypoxia (12 kPa O2), cold (5°C) normoxia or cold hypoxia. Acclimation to hypoxia and/or cold increased thermogenic capacity in deer mice, but hypoxia acclimation led to much greater increases in thermogenic capacity in highlanders than in lowlanders. The high thermogenic capacity of highlanders was associated with increases in pulmonary O2 extraction, arterial O2 saturation, cardiac output and arterial-venous O2 difference. Mechanisms underlying the evolution of enhanced thermogenic capacity in highlanders were partially distinct from those underlying the ancestral acclimation responses of lowlanders. Environmental adaptation has thus enhanced phenotypic plasticity and expanded the physiological toolkit for coping with the challenges at high altitude.
3278: The Pearce Family
Creators: name: Project Team, Lest We Forget
Publisher: name: University of Oxford
Year: 2024
Subjects: classificationCode: 430304
subject: British history
classificationCode: 430308
subject: European history (excl. British, classical Greek and Roman)
classificationCode: 430316
subject: International history

description: Comparatively rarely for the time, Joseph (Joe) Pearce was able to drive and joined up as a driver. Was assigned as an ambulance driver, part of a motor ambulance convoy transferring the wounded from France to hospitals in Kent. Towards the end of the war his wife wrote to the war office requesting his early release as he was needed at home on the farm. Captain Stewart-Liberty, the local landowner, (see separate entry) declared "that letter won't do it!" and wrote personally himself. Joe was soon home.

His brother Samuel David Pearce (Dave) also saw action in the war. Was wounded in the wrist, apparently the bullet came out at his elbow. He was also gassed and received the military medal. Joe's son Philip recalls seeing a military aircraft land at Hampden's Piece, a large field by White Lion Hill in The Lee, towards the end of the war. A large crowd gathered including the police. Philip followed the pilot who was accompanied by a police escort before he was told to "clear off!"
Searching for primordial helical magnetic fields
Creators: name: Kachelriess, M.
name: Martinez, B. C.
Publisher: name: arXiv
Year: 2020
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: The presence of non-zero helicity in intergalactic magnetic fields (IGMF) has been suggested as a clear signature for their primordial origin. We extend a previous analysis of diffuse Fermi-LAT gamma-ray data from 2.5 to more than 11 years and show that a hint for helical magnetic fields in the 2.5 year data was a statistical fluctuation. Then we examine the detection prospects of helical magnetic fields using individual sources as, e.g., TeV gamma-ray blazars. We find that a detection is challenging employing realistic models for the cascade evolution, the IGMF and the detector resolution in our simulations.
description: 10 pages, 14 png figures; v2: improved quality of the figures, matches published version
Electronic Supplementary Material from The optimal timing of teaching and learning across the life course
Creators: name: Gurven, Michael D.
name: Raziel J. Davison
name: Kraft, Thomas S.
Publisher: name: The Royal Society
Year: 2020
Subjects: subject: Evolutionary Biology
subject: FOS: Biological sciences
subject: 60801 Animal Behaviour

description: Extra Methods & Supplemental Figures
Improving Fuzzy-Logic based Map-Matching Method with Trajectory Stay-Point Detection
Creators: name: Jafarlou, Minoo
name: E., Omid Mahdi Ebadati
name: Naderi, Hassan
Publisher: name: arXiv
Year: 2022
Subjects: subject: Machine Learning (cs.LG)
subject: Artificial Intelligence (cs.AI)
subject: Computational Geometry (cs.CG)
subject: Computer Vision and Pattern Recognition (cs.CV)
subject: Logic in Computer Science (cs.LO)
subject: FOS: Computer and information sciences

description: The requirement to trace and process moving objects in the contemporary era gradually increases since numerous applications quickly demand precise moving object locations. The Map-matching method is employed as a preprocessing technique, which matches a moving object point on a corresponding road. However, most of the GPS trajectory datasets include stay-points irregularity, which makes map-matching algorithms mismatch trajectories to irrelevant streets. Therefore, determining the stay-point region in GPS trajectory datasets results in better accurate matching and more rapid approaches. In this work, we cluster stay-points in a trajectory dataset with DBSCAN and eliminate redundant data to improve the efficiency of the map-matching algorithm by lowering processing time. We reckoned our proposed method's performance and exactness with a ground truth dataset compared to a fuzzy-logic based map-matching algorithm. Fortunately, our approach yields 27.39% data size reduction and 8.9% processing time reduction with the same accurate results as the previous fuzzy-logic based map-matching approach.
description: 10 Pages, 20 Figures
X-ray properties of the transient pulsar 3A 0535+262 in quiescence
Creators: name: Mukherjee, U.
name: Paul, B.
Publisher: name: arXiv
Year: 2004
Subjects: subject: Data Analysis, Statistics and Probability (physics.data-an)
subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We present the timing and spectral properties of the transient Be/X-ray binary pulsar 3A 0535+262 during quiescence using three observations with the narrow field imaging instruments (NFI) of BeppoSAX. Assuming a distance of 2 kpc for this system, the 2-10 keV X-ray luminosities measured from the three observations are in the range of 1.5-4.0 $\times$ 10$^{33}$ erg s$^{-1}$, indicating a very low rate of accretion. We report the detection of pulsations at a very low luminosity of 2 $\times$ 10$^{33}$ erg s$^{-1}$ during one of the three observations, though at this accretion rate the system is expected to be in the centrifugally inhibited regime. The X-ray spectra for the unpulsed observations are best modeled as power law type while a combined model of power law and black-body is required to fit the pulsed spectrum.
description: 13 pages, 6 figures, accepted in Astronomy and Astrophysics
Annual parallax measurement of a Mira variable star BX Cam with VERA
Creators: name: Matsuno, Masako
name: Nakagawa, Akiharu
name: Morita, Atsushi
name: Kurayama, Tomoharu
name: Omodaka, Toshihiro
name: Nagayama, Takumi
name: Honma, Mareki
name: Shibata, Katsunori M
name: Ueno, Yuji
name: Jike, Takaaki
name: Tamura, Yoshiaki
Publisher: name: arXiv
Year: 2020
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We report results of astrometric VLBI observations toward a Mira variable star BX~Cam using the VLBI array "VERA". The observations were performed from February 2012 to November 2014. Obtained parallax is 1.73$\pm$0.03 mas corresponding to a distance of 0.58$\pm$0.01 kpc. Parallax of this source was also reported in Gaia DR2 as 4.13$\pm$0.25 mas, and there is a 240 \% difference between these two measurements. Astrometric results from our VLBI observations show that we exactly traced angular motions of the seven maser spots in BX~Cam. We calculated stellar luminosities using both parallaxes, and obtained luminosities of $L_{\ast}^{\mathrm{VERA}} = 4950\pm170 L_{\odot}$ and $L_{\ast}^{\mathrm{Gaia}} = 870\pm110 L_{\odot}$. Deduced luminosities also support a validity of the parallax that we determined with VERA. Evaluating the two parallaxes, we concluded that the parallax of 1.73$\pm$0.03 mas from the VERA observations is correct for BX~Cam. We obtained a systemic motion of BX~Cam as (${μ_α}\cosδ^{\mathrm{sys}}$, $μ_δ^{\mathrm{sys}}$) $=$ (13.48$\pm$0.14, $-$34.30$\pm$0.18) mas\,yr$^{-1}$. A total of 73 H$_2$O maser spots detected from our VLBI observations show a spatial distribution of 30 au $\times$ 80 au with a strong elongation along north-south direction. They show outflows with a three-dimensional velocity of 14.79$\pm$1.40 km\,s$^{-1}$. From a comparison between time variations of $V$-band magnitudes and H$_2$O maser, we found that variation of the H$_2$O maser is relevant to that seen in $V$-band even though the H$_2$O maser does not recover its maximum flux in each cycle.
description: 10 pages, 6 figures, 5 tables, Accepted by PASJ
2231: Ivor Stewart-Liberty
Creators: name: Project Team, Lest We Forget
Publisher: name: University of Oxford
Year: 2024
Subjects: classificationCode: 430304
subject: British history
classificationCode: 430308
subject: European history (excl. British, classical Greek and Roman)
classificationCode: 430316
subject: International history

description: Ivor Stewart Liberty served as a Captain in the 2/1 Bucks Battalion. Was wounded at Fromelles in July 1916. Was awarded the MC.
title: E-Commerce in India : a case study of Amazon & Flipkart (India)
Creators: name: Karal, Dipin
Publisher: name: TU Wien
Year: 2016
Subjects: subject: E-commerce
subject: Logistics
subject: Amazon
subject: Flipkart
subject: Internet

description: In the last two decade, world has witness an incredible growth of Internet and has changed the way organization conduct business. It has provided a new option for conducting business named e-commerce. It is basically selling and buying through internet using computers. The purpose of this study is to first understand the e-commerce and its impacts. Further understanding of logistics and its role in e-commerce. A case study of Amazon and Flipkart India is then done to explore its business strategies, operation, logistics functioning etc. Cross analysis of Amazon and Flipkart in term of market share, revenue etc. is done next. A SWOT and PORTER analysis is then performed based on it. It helped in coming to the conclusion about future strategies needed by both companies to remain competitive. To reach this purpose, a qualitative research approach was used where case study on Amazon India is conducted. The data is collected through books, Internet and interviews. The finding of our analysis shows that despite increased revenue and sales both Amazon and Flipkart still faces many challenges such as IT security - vulnerability to hacking, low margins due heavy discounting, loopholes in distribution system etc. During festival time when sales are usually at peak many complain occurs such as late delivery, website non-functioning which seriously impact the company image and operational capabilities. In the conclusions, some of the major threats that are affecting both the companies is discussed such as heavy losses due to discount, logistics inefficiency, expansion to smaller cities etc. To counter it, the steps taken by both the companies such as new payment gateways etc is also discussed.
Forward doubly-virtual Compton scattering off the nucleon in chiral perturbation theory: the subtraction function and moments of unpolarized structure functions
Creators: name: Alarcón, Jose Manuel
name: Hagelstein, Franziska
name: Lensky, Vadim
name: Pascalutsa, Vladimir
Publisher: name: arXiv
Year: 2020
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Lattice (hep-lat)
subject: Nuclear Experiment (nucl-ex)
subject: Nuclear Theory (nucl-th)
subject: Atomic Physics (physics.atom-ph)
subject: FOS: Physical sciences

description: The forward doubly-virtual Compton scattering (VVCS) off the nucleon contains a wealth of information on nucleon structure, relevant to the calculation of the two-photon-exchange effects in atomic spectroscopy and electron scattering. We report on a complete next-to-leading-order (NLO) calculation of low-energy VVCS in chiral perturbation theory ($χ$PT). Here we focus on the unpolarized VVCS amplitudes $T_1(ν, Q^2)$ and $T_2(ν, Q^2)$, and the corresponding structure functions $F_1(x, Q^2)$ and $F_2(x,Q^2)$. Our results are confronted, where possible, with "data-driven" dispersive evaluations of low-energy structure quantities, such as nucleon polarizabilities. We find significant disagreements with dispersive evaluations at very low momentum-transfer $Q$; for example, in the slope of polarizabilities at zero momentum-transfer. By expanding the results in powers of the inverse nucleon mass, we reproduce the known "heavy-baryon" expressions. This serves as a check of our calculation, as well as demonstrates the differences between the manifestly Lorentz-invariant (B$χ$PT) and heavy-baryon (HB$χ$PT) frameworks.
description: 31 pages, 11 figures, 1 table; supplemented material: 1 Mathematica notebook; minor modifications, published version
Double-Loop Importance Sampling for McKean--Vlasov Stochastic Differential Equation
Creators: name: Rached, Nadhir Ben
name: Haji-Ali, Abdul-Lateef
name: Pillai, Shyam Mohan Subbiah
name: Tempone, Raúl
Publisher: name: arXiv
Year: 2022
Subjects: subject: Numerical Analysis (math.NA)
subject: Computation (stat.CO)
subject: FOS: Mathematics
subject: FOS: Computer and information sciences
subject: 60H35. 65C30. 65C05. 93E20. 65C35

description: This paper investigates Monte Carlo (MC) methods to estimate probabilities of rare events associated with solutions to the $d$-dimensional McKean-Vlasov stochastic differential equation (MV-SDE). MV-SDEs are usually approximated using a stochastic interacting $P$-particle system, which is a set of $P$ coupled $d$-dimensional stochastic differential equations (SDEs). Importance sampling (IS) is a common technique for reducing high relative variance of MC estimators of rare-event probabilities. We first derive a zero-variance IS change of measure for the quantity of interest by using stochastic optimal control theory. However, when this change of measure is applied to stochastic particle systems, it yields a $P \times d$-dimensional partial differential control equation (PDE), which is computationally expensive to solve. To address this issue, we use the decoupling approach introduced in [dos Reis et al., 2023], generating a $d$-dimensional control PDE for a zero-variance estimator of the decoupled SDE. Based on this approach, we develop a computationally efficient double loop MC (DLMC) estimator. We conduct a comprehensive numerical error and work analysis of the DLMC estimator. As a result, we show optimal complexity of $\mathcal{O}(\mathrm{TOL}_{\mathrm{r}}^{-4})$ with a significantly reduced constant to achieve a prescribed relative error tolerance $\mathrm{TOL}_{\mathrm{r}}$. Subsequently, we propose an adaptive DLMC method combined with IS to numerically estimate rare-event probabilities, substantially reducing relative variance and computational runtimes required to achieve a given $\mathrm{TOL}_{\mathrm{r}}$ compared with standard MC estimators in the absence of IS. Numerical experiments are performed on the Kuramoto model from statistical physics.
2498: The Bowman Family of Corbridge, Northumberland
Creators: name: Project Team, Lest We Forget
Publisher: name: University of Oxford
Year: 2024
Subjects: classificationCode: 430304
subject: British history
classificationCode: 430308
subject: European history (excl. British, classical Greek and Roman)
classificationCode: 430316
subject: International history

description: Photographs and material relating to the Bowman family, farmers in Corbridge, Northumberland, whose sons Frederick and Charles went to the front with the Northumberland Fusiliers. Both were killed. Charles was awarded the Military Medal.
title: Revenue forecasting based on business opportunities
Creators: name: Hauser, Fabian
Publisher: name: TU Wien
Year: 2016
Subjects: subject: Sales forecast
subject: Cognitive bias
subject: Data analysis
subject: Regression
subject: Resampling
subject: Value at Risk

description: CRM Opportunity data from a corporation are analysed for patterns. These data is created from salesmen and provide business opportunity information with win probabilities and volumes. The first step of the analysis is to create crosstables. In the table, observed probabilities and subjective probabilities vary a lot. We also check for probability independencies of opportunities at MDF compared to EFY volumes. As a result, we do not find dependences. The sum of all open weighed MFY opportunities from FY 2012 - 2015 calculated as a forecast for the EFY total volume is â¬ 168.712.641. The realized volume is however â¬ 53.178.551, that is only 33.8% of all weighted opportunities. Even if we assume that we have only the prior knowledge, the 30.6% of the FY are successful, the subjective probabilities are actually pointing into the wrong direction and we obtain a much better EFY estimation than using the subjective probabilities. There is no relationship between the subjective probability judgment and the won opportunities. Finally, a way is found to smooth the crosstable with a logarithm, where again similar probability categories are aggregated to make relationships clearer. In the end, it is clear to see that small volume opportunities tend to have higher success rates than large volume opportunities. Further a model with a deviation of less than 1% is found and a 10% VaR is calculated. It turns out that the model with three sized categories is the favourable, because 10 size categories seem too many and likely create an overfitting effect within the data. The main conclusion is that the company has an issue of very overoptimistic salesmen. We propose not to rely on the -experience- of the salesmen but consider the size of an OI as relevant indicator. Small and medium OIs have higher success probabilities than the average, while large OIs have much smaller ones. Big opportunities are won rather rarely (18%). Maybe the corporation should invest more in their acquirement efforts for big projects. However, a goal needs to be for this company to train their sales staff to make them more sensitive for their business estimations to get better data input and concluding to more data that are reliable to process
Critical non-Hermitian Skin Effect
Creators: name: Li, Linhu
name: Lee, Ching Hua
name: Mu, Sen
name: Gong, Jiangbin
Publisher: name: arXiv
Year: 2020
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: This work uncovers a new class of criticality where eigenenergies and eigenstates of non-Hermitian lattice systems jump discontinuously across a critical point in the thermodynamic limit, unlike established Hermitian and non-Hermitian critical scenarios where spectrum remains continuous across a transition. Such critical behavior, dubbed the "critical skin effect", is rather generic, occuring whenever subsystems with dissimilar non-Hermitian skin localization lengths are coupled, however weakly. Due to the existence of this criticality, the thermodynamic limit and the zero-coupling limit cannot be exchanged, thus challenging the celebrated generalized Brillouin zone (GBZ) approach when applied to finite-size systems. As manifestations of the critical skin effect in finite-size systems, we present stimulating examples with anomalous scaling behavior regarding spectrum, correlation functions, entanglement entropy, and scale-free wavefunctions that decay exponentially rather than power-law. More spectacularly, topological in-gap modes can even be induced by changing the system size.
description: 4+ pages of main text (including 4 figures), plus 6 pages of Supplementary Material (including 7 figures)
THE POTENTIAL USE OF FARMER FIELD SCHOOLS WITHIN THE ENGLISH SPEAKING CARIBBEAN
Creators: name: Dolly, David
name: Dolly, David
Publisher: name: Unknown
Year: 2001
Subjects: Crop Production/Industries
Farm Management

description: Farmer Field Schools (FFS) have become a useful institution in facilitating an integrated approach to Integrated Pest Management (IPM). It has been viewed as an impressive advance in IPM implementation over the last decade (Ter Wheel and Van Der Wulp, 1999). Its impact is well documented among the rice production systems of small farmers in The Philippines, Indonesia, Vietnam and India. For instance in Indonesia following the implementation of FFS, rice farmers were able to reduce pesticide use by 60% with an accompanying yield increase of 13% (Kairo, 2000). Similarly in the Philippines there was a recorded 80% decrease in the use of insecticide among vegetable growers. There have also been many success stories out of Central America. This presentation explores potential use of this methodology within the English Speaking Caribbean.
title: Outsourcing Network Maintenance activities in telecommunications HFC network and CPE Maintenance Activities
Creators: name: Nazifi, Prparim
Publisher: name: TU Wien
Year: 2016
Subjects: subject: Telecommunication
subject: Business Process Outsourcing
subject: Hybrid Fiber-Coaxial
subject: High Speed Internet

description: Outsourcing, -outside resourcing- term used first by Americans, as an economic process, did not start happening recently. Companies have been outsourcing their non-core services or functions for many years now. At first, the key driver for outsourcing was reducing and controlling of Operational Expenditures (OPEX) but over the time few other factors emerged as important drivers such as providing higher quality services to end-customers, flexibility in control of resources (human and material), risk sharing with the outsourcing partners, access to specialized expertise and competencies, long term strategic relationship and partnership foundations, etc. Considering the above mentioned factors, drivers and potential benefits, all kind of companies, including telecom operators, more and more decide to outsource their non-core activities such as Inbound Customer Service & Technical support, IT Help Desk, Application Maintenance, Outbound Telesales Collections and Customer Call Backs, Sales Support, Field Force Management etc. Generally, outsourcing as a concept is proven to be successful and overtime fulfilling the objective that the company aimed to achieve when started doing it, however we have to emphasize that the overall process is filled with hurdles and challenges and it is a time-consuming process. This master thesis aims to describe outsourcing process of Field Force activities related to Hybrid Fiber-Coaxial (HFC) network maintenance including the Customer Premises Equipment (CPE) and its installation maintenance. Using already known Business Process Outsourcing (BPO) frameworks this thesis will describe phases on how to implement the outsourcing process of these activities to a subcontracting company. The thesis is built with the assumption that the objectives are known and well evidenced. Based on those assumptions decision to outsource these processes is already made therefore will not be in the scope of this master thesis.
Politics and IMF Conditionality
Creators: name: Sturm, Jan-Egbert
name: Dreher, Axel
name: Vreeland, James R.
Publisher: name: ETH Zurich
Year: 2013
Subjects: Conditionality
STIMMABGABE (INNENPOLITIK)
VOTINGS + BALLOTS (INTERNAL POLITICS)
INTERNATIONAL MONETARY FUND
INTERNATIONALER WÄHRUNGSFONDS
INTERNATIONAL ECONOMIC AID
UN Security Council
ECONOMIC DEVELOPMENT
SPECIAL ORGANISATIONS OF UNITED NATIONS, UN (INTERNATIONAL LAW)
WIRTSCHAFTSENTWICKLUNG
ZWISCHENSTAATLICHE WIRTSCHAFTSHILFE
Aid
IMF
Voting
SONDERORGANISATIONEN DER VEREINIGTEN NATIONEN, UN (INTERNATIONALES RECHT)
info:eu-repo/classification/ddc/330
Economics

description: KOF Working Papers, 338
title: Company valuation methods and their practical relevance
Creators: name: Weitl, Georg
Publisher: name: TU Wien
Year: 2016
Subjects: subject: Company valuation
subject: Discounted cash flow
subject: Valuation multiples

description: The topic company valuation is one of the most significant areas of business administration but also one of the most controversial. In the literature there can be found a broad spectrum of methods and concepts for the valuation of companies with a difference in the complexity of its application. The aim of this master thesis is to give an overview of the topic company valuation and the existing valuation methods and to provide a better understanding, which methods are actually used in practice and what are the details that have to be considered. The methods of company valuation can be classified in three basic groups depending if they are focusing only on the values of the single components of the company, the company as one unit that is a compositions of its assets, or on something in between. The most common method used internationally and also the most practical relevance has the discounted cash flow method (DCF) with its three approaches. But typically not only one method is used but a combination of the DCF method and the multiple-based approach to validate the results is applied. Under the discounted cash flow method there exist three approaches, the WACC- (weighted average cost of capital), the APV- (adjusted present value), and the FtE- (flow to equity) approach. The individual variants of the DCF-method distinguish themselves basically in the manner of calculating the shareholder value directly (equity approach) or indirectly (entity approach), and how the tax advantage due to debt financing (tax shield) is used. The aim of all approaches is to determine the market value of the company respectively its equity and therefore estimating the present value of a company by discounting its future payments, the free cash flows (FCF). The estimation and forecasting of the free cash flows is done based on an analysis of the valuation object, it-s historical performance, and the market environment. In order to perform the calculation of the discounted cash flows it is necessary to determine the costs of equity based on the capital asset pricing model and the costs of debt. The multiple-based approaches are using the known market prices of other companies to calculate multiples that are then taken to valuate the object company. There is the possibility to either taking the market price of stock exchange listed companies or using the market price of recently acquired comparable companies. For the selection of comparable companies or transactions it is important that they share the same characteristics as the valuation object.
Cone-Restricted Information Theory
Creators: name: George, Ian
name: Chitambar, Eric
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Physics (quant-ph)
subject: Information Theory (cs.IT)
subject: FOS: Physical sciences
subject: FOS: Computer and information sciences

description: The max-relative entropy and the conditional min-entropy it induces have become central to one-shot information theory. Both may be expressed in terms of a conic program over the positive semidefinite cone. Recently, it was shown that the same conic program altered to be over the separable cone admits an operational interpretation in terms of communicating classical information over a quantum channel. In this work, we generalize this framework of replacing the cone to determine which results in quantum information theory rely upon the positive semidefinite cone and which can be generalized. We show the fully quantum Stein's lemma and asymptotic equipartition property break down if the cone exponentially increases in resourcefulness but never approximates the positive semidefinite cone. However, we show for CQ states, the separable cone is sufficient to recover the asymptotic theory, thereby drawing a strong distinction between the fully and partial quantum settings. We present parallel results for the extended conditional min-entropy. In doing so, we extend the notion of k-superpositive channels to superchannels. We also present operational uses of this framework. We first show the cone restricted min-entropy of a Choi operator captures a measure of entanglement-assisted noiseless classical communication using restricted measurements. We show that quantum majorization results naturally generalize to other cones. As a novel example, we introduce a new min-entropy-like quantity that captures the quantum majorization of quantum channels in terms of bistochastic pre-processing. Lastly, we relate this framework to general conic norms and their non-additivity. Throughout this work we emphasize the introduced measures' relationship to general convex resource theories. In particular, we look at both resource theories that capture locality and resource theories of coherence/Abelian symmetries.
description: Updated formatting, terminology, and some of the presentation for clarity. Some typos fixed as well
Electrostatics and the Assembly of an RNA Virus
Creators: name: van der Schoot, P.
name: Bruinsma, R.
Publisher: name: arXiv
Year: 2004
Subjects: subject: Biomolecules (q-bio.BM)
subject: Subcellular Processes (q-bio.SC)
subject: FOS: Biological sciences

description: Electrostatic interactions play a central role in the assembly of single-stranded RNA viruses. Under physiological conditions of salinity and acidity, virus capsid assembly requires the presence of genomic material that is oppositely charged to the core proteins. In this paper we apply basic polymer physics and statistical mechanics methods to the self-assembly of a synthetic virus encapsidating generic polyelectrolyte molecules. We find that (i) the mean concentration of the encapsidated polyelectrolyte material depends on the surface charge density, the radius of the capsid, and the linear charge density of the polymer but neither on the salt concentration or the Kuhn length, (ii) the total charge of the capsid interior is equal but opposite to that of the empty capsid, a form of charge reversal. Unlike natural viruses, synthetic viruses are predicted not to be under an osmotic swelling pressure. The design condition that self-assembly only produces filled capsids is shown to coincide with the condition that the capsid surface charge exceeds the desorption threshold of polymer surface adsorption. We compare our results with studies on the self-assembly of both synthetic and natural viruses.
description: 41 pages, 4 figures