cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Dyadic partition-based training schemes for TV/TGV denoising
Creators: name: Davoli, Elisa
name: Ferreira, Rita
name: Fonseca, Irene
name: Iglesias, José A.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Analysis of PDEs (math.AP)
subject: Optimization and Control (math.OC)
subject: FOS: Mathematics
subject: 68U10, 26A45, 49J10, 94A08

description: Due to their ability to handle discontinuous images while having a well-understood behavior, regularizations with total variation (TV) and total generalized variation (TGV) are some of the best-known methods in image denoising. However, like other variational models including a fidelity term, they crucially depend on the choice of their tuning parameters. A remedy is to choose these automatically through multilevel approaches, for example by optimizing performance on noisy/clean image pairs. In this work, we consider such methods with space-dependent parameters which are piecewise constant on dyadic grids, with the grid itself being part of the minimization. We prove existence of minimizers for fixed discontinuous parameters under mild assumptions on the data, which lead to existence of finite optimal partitions. We further establish that these assumptions are equivalent to the commonly used box constraints on the parameters. On the numerical side, we consider a simple subdivision scheme for optimal partitions built on top of any other bilevel optimization method for scalar parameters, and demonstrate its improved performance on some representative test images when compared with constant optimized parameters.
description: 45 pages, 6 figures, 1 table
Novel shadows from the asymmetric thin-shell wormhole
Creators: name: Wang, Xiaobao
name: Li, Peng-Cheng
name: Zhang, Cheng-Yong
name: Guo, Minyong
Publisher: name: arXiv
Year: 2020
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: For dark compact objects such as black holes or wormholes, the shadow size has long been thought to be determined by the unstable photon sphere (region). However, by considering the asymmetric thin-shell wormhole (ATSW) model, we find that the impact parameter of the null geodesics is discontinuous through the wormhole in general and hence we identify novel shadows whose sizes are dependent of the photon sphere in the other side of the spacetime. The novel shadows appear in three cases: (A2) The observer's spacetime contains a photon sphere and the mass parameter is smaller than that of the opposite side; (B1, B2) there' s no photon sphere no matter which mass parameter is bigger. In particular, comparing with the black hole, the wormhole shadow size is always smaller and their difference is significant in most cases, which provides a potential way to observe wormholes directly through Event Horizon Telescope with better detection capability in the future.
description: 5 pages, 4 figures, published in PLB
National treatment, transparency, and rule of law : evolving issues on the conformity of China’s legal system with WTO’s principles
Creators: name: Wang, Chao
Publisher: name: University of British Columbia
Year: 2009

description: Following the trends of the Globalization, the principles of Nondiscrimination, Transparency and Rule of Law, are all becoming the core principles of globalized norms of economic regulation, which have always known to be associated with GATT and the World Trade Organization (WTO). Following the accession of the People's Republic of China to the WTO, it is well understood that the requirements for the conformity of laws and regulations inside and outside of China to WTO are high, especially in terms of the conformity of China's regulatory system of economic regulations to WTO's Principles of national treatment, transparency, and rule of law. This paper will examine the conformity of WTO's Principles of National Treatment, Transparency, and Rule of Law with China's regulatory system of economic regulation, especially with a focus on the compliance of globalized norms of economic regulation with China's local norms and local values, and the legal and political culture. At the same time, this paper aims to discover the institutional approaches that protect and facilitate judicial independence. Attention is also paid to the influences of the institutions system on impartiality and accountability of judicial practice through facilitating judicial independence.
Radiative decays of the Sigma0(1385) and Lambda(1520) hyperons
Creators: name: Taylor, S.
name: Mutchler, G. S.
Publisher: name: arXiv
Year: 2005
Subjects: subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: The electromagnetic decays of the Sig0(1385) and Lambda(1520) hyperons were studied in photon-induced reactions gamma p -> K+ Lambda(1116)gamma in the CLAS detector at the Thomas Jefferson National Accelerator Facility. We report the first observation of the radiative decay of the Sig0(1385) and a measurement of the Lambda(1520) radiative decay width. For the Sig0(1385) -> Lambda(1116)gamma transition, we measured a partial width of 479+/-120(stat)+81-100(sys) keV, larger than all of the existing model predictions. For the Lambda(1520) -> Lambda(1116)gamma transition, we obtained a partial width of 167+/-43(stat)+26-12(sys) keV.
description: 15 pages, 19 eps figures, revtex4, accepted for publication Phys. Rev. C. Additional reference added with discusion in introduction and results sectons. Figure 17 has been corrected
Probing spectral features of quantum many-body systems with quantum simulators
Creators: name: Sun, Jinzhao
name: Vilchez-Estevez, Lucia
name: Vedral, Vlatko
name: Boothroyd, Andrew T.
name: Kim, M. S.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Quantum Physics (quant-ph)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Computational Physics (physics.comp-ph)
subject: FOS: Physical sciences

description: The efficient probing of spectral features is important for characterising and understanding the structure and dynamics of quantum materials. In this work, we establish a framework for probing the excitation spectrum of quantum many-body systems with quantum simulators. Our approach effectively realises a spectral detector by processing the dynamics of observables with time intervals drawn from a defined probability distribution, which only requires native time evolution governed by the Hamiltonian without ancilla. The critical element of our method is the engineered emergence of frequency resonance such that the excitation spectrum can be probed. We show that the time complexity for transition energy estimation has a logarithmic dependence on simulation accuracy and how such observation can be guaranteed in certain many-body systems. We discuss the noise robustness of our spectroscopic method and show that the total running time maintains polynomial dependence on accuracy in the presence of device noise. We further numerically test the error dependence and the scalability of our method for lattice models. We present simulation results for the spectral features of typical quantum systems, either gapped or gapless, including quantum spins, fermions and bosons. We demonstrate how excitation spectra of spin-lattice models can be probed experimentally with IBM quantum devices.
description: 29 pages, 12 figures
Formal Controller Synthesis for Frequency Regulation Utilising Electric Vehicles
Creators: name: Wooding, Ben
name: Vahidinasab, Vahid
name: Soudjani, Sadegh
Publisher: name: arXiv
Year: 2020
Subjects: subject: Systems and Control (eess.SY)
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: In this paper, we propose a formal controller synthesis approach for integrating a population of plug-in electric vehicles in frequency regulation of power systems. This approach is the first application of formal methods to the smart grids in particular to the frequency regulation of power systems. We design and simulate a novel symbolic controller for the Great Britain power system. The proposed controller enhances the frequency response behaviour of the system when encountered with a large outage event. The symbolic controller guarantees the settlement of the after-event's frequency in the specified safe interval and ensures other requirements on the frequency are met.
description: 9 Pages, 12 figures, 2 tables
On Seshadri constants and point-curve configurations
Creators: name: Janasz, Marek
name: Pokora, Piotr
Publisher: name: arXiv
Year: 2020
Subjects: subject: Algebraic Geometry (math.AG)
subject: FOS: Mathematics
subject: 14C20, 14N10

description: In the note we study the multipoint Seshadri constants of $\mathcal{O}_{\mathbb{P}^{2}_{\mathbb{C}}}(1)$ centered at singular loci of certain curve arrangements in the complex projective plane. Our first aim is to show that the values of Seshadri constants can be approximated with use of a combinatorial invariant which we call the configurational Seshadri constant. We study specific examples of point-curve configurations for which we provide actual values of the associated Seshadri constants. In particular, we provide an example based on Hesse point-conic configuration for which the associated Seshadri constant is computed by a line. This shows that multipoint Seshadri constants are not purely combinatorial.
description: 12 pages, accepted in Electronic Research Archive
Proposed Harbor Island Seawater Reverse Osmosis Desalination Facility
Creators: name: Nielsen, Kristin
Publisher: name: The University of Texas at Austin
Year: 2021
Subjects: POCC
TCEQ

description: In 2018, the Port of Corpus Christi Authority of Nueces County (POCC) submitted an Industrial Wastewater Permit Application to the Texas Commission on Environmental Quality (TCEQ), which outlines proposed plans to construct a seawater desalination plant capable of generating up to 50 million gallons of potable water per day (MGD) at the former Atofina and Exxon Tank Terminal site on Harbor Island.1, 2 In order to operate at full capacity, models indicate that the offshore intake will need to draw in 150.7 million gallons of raw seawater (with an expected salinity range of 32 – 35 parts per thousand [ppt]) each day, approximately 33.2% (equivalent to 50 MGD) of which will be converted to potable water. The vast majority of the unusable fraction of intake water (approximately 63.4% of the total volume of intake water or the equivalent of 95.5 MGD) will be discharged into the Corpus Christi Shipping Channel (CCSC) daily via a multi-port diffuser. Effluent from the facility (i.e., a mixture of membrane reject and water mechanically extracted from sludge) will contain nearly all of the dissolved and suspended constituents present in raw intake media, including chemical toxicants present as source pollution and additional chemicals added as part of the desalination process.3 The remaining 3.4% of the daily intake water volume (equivalent to 5.1 MGD) will enter a nearby landfill as solid sludge.1, 2 Due to the high productivity and ecological value of the habitat in proximity to the site of the proposed facility, it is imperative that all potential ecological risks be thoroughly evaluated prior to project approval and initiation. The potential risks associated with impingement, entrapment and entrainment of aquatic biota (at the seawater intake site), altered hydrodynamics, changes in the transport and settling of larval fishes, and increasing salinity in the CCSC have been evaluated elsewhere. Therefore, the goal of the present report is to prospectively evaluate the potential ecotoxicological risks associated with discharge of effluent from the proposed facility to the CCSC and surrounding habitat.
Additional file 3 of The disease burden in patients with respiratory allergies induced by house dust mites: a year-long observational survey in three European countries
Creators: name: Demoly, Pascal
name: Matucci, Andrea
name: Rossi, Oliviero
name: Vidal, Carmen
Publisher: name: figshare
Year: 2020
Subjects: subject: Medicine
subject: Immunology
subject: FOS: Clinical medicine
subject: 69999 Biological Sciences not elsewhere classified
subject: FOS: Biological sciences
subject: Science Policy

description: Additional file 3: Figure S2.Fortnightly telephone interviews of ‘HDM-only’ participants: the impact of the HDM allergy on six types of activity from Jan 2013 to late July 2013, shown against the symptom intensity. The size of the bubble is proportional (albeit not exactly) to the proportion of participants reporting an impact.
The plaquette phase of the square lattice quantum dimer model
Creators: name: Syljuasen, Olav F.
Publisher: name: arXiv
Year: 2005
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: The plaquette phase of the square lattice quantum dimer model is studied using a continuous-time reptation quantum Monte Carlo method for lattices of sizes up to 48x48 sites. We determine the location of the phase transition between the columnar and plaquette phases to occur at V_c/J=0.60 +- 0.05 which is significantly larger than inferred from previous exact diagonalization studies on smaller lattices. Offdiagonal correlation functions are obtained. They exhibit long-range order in the plaquette phase but not at the Rokhsar-Kivelson point. We also observe significant finite-size corrections to scaling for the transition between the plaquette phase and the critical resonating valence bond liquid. This study demonstrates the importance of understanding finite-size effects when considering critical properties of the square lattice quantum dimer model.
description: 10 pages, 18 figures, considerably revised version
DeRi-Bot: Learning to Collaboratively Manipulate Rigid Objects via Deformable Objects
Creators: name: Wang, Zixing
name: Qureshi, Ahmed H.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Robotics (cs.RO)
subject: FOS: Computer and information sciences

description: Recent research efforts have yielded significant advancements in manipulating objects under homogeneous settings where the robot is required to either manipulate rigid or deformable (soft) objects. However, the manipulation under heterogeneous setups that involve both rigid and one-dimensional (1D) deformable objects remains an unexplored area of research. Such setups are common in various scenarios that involve the transportation of heavy objects via ropes, e.g., on factory floors, at disaster sites, and in forestry. To address this challenge, we introduce DeRi-Bot, the first framework that enables the collaborative manipulation of rigid objects with deformable objects. Our framework comprises an Action Prediction Network (APN) and a Configuration Prediction Network (CPN) to model the complex pattern and stochasticity of soft-rigid body systems. We demonstrate the effectiveness of DeRi-Bot in moving rigid objects to a target position with ropes connected to robotic arms. Furthermore, DeRi-Bot is a distributive method that can accommodate an arbitrary number of robots or human partners without reconfiguration or retraining. We evaluate our framework in both simulated and real-world environments and show that it achieves promising results with strong generalization across different types of objects and multi-agent settings, including human-robot collaboration.
description: This paper has been accepted by IEEE RA-L
Magnetic exchange coupling in cuprate-analog $d^9$ nickelates
Creators: name: Nomura, Yusuke
name: Nomoto, Takuya
name: Hirayama, Motoaki
name: Arita, Ryotaro
Publisher: name: arXiv
Year: 2020
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Materials Science (cond-mat.mtrl-sci)
subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: Motivated by the recent discovery of superconductivity in doped NdNiO$_2$, we study the magnetic exchange interaction $J$ in layered $d^9$ nickelates from first principles. The mother compounds of the high-$T_{\rm c}$ cuprates belong to the charge-transfer regime in the Zaanen-Sawatzky-Allen diagram and have $J$ larger than 100 meV. While this feature makes the cuprates very different from other transition metal oxides, it is of great interest whether layered $d^9$ nickelates can also have such a large $J$. However, one complexity is that NdNiO$_2$ is not a Mott insulator due to carrier doping from the block layer. To compare the cuprates and $d^9$ nickelates on an equal basis, we study RbCa$_2$NiO$_3$ and $A_{2}$NiO$_{2}$Br$_2$ ($A$: a cation with the valence of $2.5+$), which were recently designed theoretically by block-layer engineering. These nickelates are free from the self-doping effect and belong to the Mott-Hubbard regime. We show that these nickelates share a common thread with the high-$T_{\rm c}$ cuprates in that they also have a significant exchange interaction $J$ as large as about 100 meV.
description: 10 pages, 3 figures
title: Le jeu récurrent de la norme et de la transgression dans Erasure de Percival Everett
Creators: name: Chauche, Catherine
Publisher: name: Savoirs en prisme
Year: 2013

description: Le protagoniste-narrateur d’Erasure, le roman de Percival Everett, vend son âme au diable en acceptant que sa parodie du roman afro-américain soit prise au sérieux et récompensée par un jury littéraire qu’il méprise, mais dont il fait partie : d’emblée, le récit va s’articuler autour de la dynamique norme/transgression. Notre propos sera de montrer que le mouvement qui porte cette dynamique dans l’entier du roman se calque sur le cinétisme du système de l’article anglais, tel qu’il a été mis au jour par le linguiste français Gustave Guillaume, et que la posture existentielle d’un homme aussi rebelle que conformiste peut se décliner grammaticalement selon les emplois possibles du substantif « writer ».
description: Savoirs en prisme, No. 02 (2013): Normes, marges, transgressions
Conditions for detecting CP violation via neutrinoless double beta decay
Creators: name: Joniec, Alicja
name: Zralek, Marek
Publisher: name: arXiv
Year: 2004
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: Neutrinoless double beta decay data together with information on the absolute neutrino masses obtained from the future KATRIN experiment and/or astrophysical measurements give a chance to find CP violation in the lepton sector with Majorana neutrinos. We derive and discuss necessary conditions which make discovery of such CP violation possible for the future neutrino oscillation and mass measurements data.
description: 15 pages, 4 figures, RevTeX
On the Wasserstein distance and the Dobrushin uniqueness theorem
Creators: name: Dorlas, Tony C.
name: Savoie, Baptiste
Publisher: name: arXiv
Year: 2023
Subjects: subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences
subject: 2010: 82B05, 82B10, 82B20, 82B26 (Primary), 28C20, 46G10, 60B05, 60B10 (Secondary)

description: In this paper, we revisit the Dobrushin uniqueness theorem for Gibbs measures of lattice systems of interacting particles at thermal equilibrium. In a nutshell, Dobrushin's uniqueness theorem provides a practical way to derive sufficient conditions on the inverse temperature and/or model parameters assuring uniqueness of Gibbs measures by reducing the uniqueness problem to a suitable estimate of the Wasserstein distance between pairs of 1-point Gibbs measures with different boundary conditions. After proving a general result of completeness for the Wasserstein distance, we reformulate the Dobrushin uniqueness theorem in a convenient form for lattice systems of interacting particles described by Hamiltonians that are not necessarily translation-invariant with possibly infinite-range pair-potentials and with general complete metric spaces as single-spin spaces. Our reformulation includes existence, and covers both classical lattice systems and the Euclidean version of quantum lattice systems. Further, a generalization to the Dobrushin-Shlosman theorem for translation-invariant lattice systems is given. Subsequently, we give a series of applications of these uniqueness criteria to some high-temperature classical lattice systems including the Heisenberg, Potts and Ising models. An application to classical lattice systems for which the local Gibbs measures are convex perturbations of Gaussian measures is also given.
description: 66 pages - Augmented version including the Dobrushin-Shlosman theorem with a wider range of applications - Typos corrected Accepted for publication in RMP
Additional file 2 of The disease burden in patients with respiratory allergies induced by house dust mites: a year-long observational survey in three European countries
Creators: name: Demoly, Pascal
name: Matucci, Andrea
name: Rossi, Oliviero
name: Vidal, Carmen
Publisher: name: figshare
Year: 2020
Subjects: subject: Medicine
subject: Immunology
subject: FOS: Clinical medicine
subject: 69999 Biological Sciences not elsewhere classified
subject: FOS: Biological sciences
subject: Science Policy

description: Additional file 2: Figure S1.Fortnightly telephone interviews of ‘HDM-only’ participants: the impact of the HDM allergy on six types of activity from late May 2012 to December 2012, shown against the symptom intensity. The size of the bubble is proportional (albeit not exactly) to the proportion of participants reporting an impact.
ECONOMIC ASPECTS OF THE SOUTH AFRICAN FLOWER INDUSTRY
Creators: name: Van Rooyen, I.M.
name: Van Rooyen, Johan
name: Van Rooyen, I.M.
name: Van Rooyen, Johan
Publisher: name: Unknown
Year: 1998
Subjects: Agribusiness
Crop Production/Industries

description: In this paper some interesting findings from recent studies regarding the economic aspects of the South African flower industry are highlighted. By looking at South Africa’s competitiveness and doing a comparative advantage study, an international perspective is firstly developed. The contribution of the flower industry in the South African economy is then discussed. This includes a case study on flower growers in the Gauteng Province. The final section notes some challenges for this industry. This network of studies provide a basis from which a conclusion can be drawn that it would be important to structure government initiatives to assist the private sector to expand this industry. A strategic planning exercise where the South African flower industry is positioned within an international perspective as well as to take note of the current transformation stage of the economy will be required.
Future Muon Dipole Moment Measurements
Creators: name: Roberts, B. Lee
Publisher: name: arXiv
Year: 2004
Subjects: subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: From the famous experiments of Stern and Gerlach to the present, measurements of magnetic dipole moments, and searches for electric dipole moments of ``elementary'' particles have played a major role in our understanding of sub-atomic physics. In this talk I discuss the progress on measurements and theory of the magnetic dipole moment of the muon. I also discuss a new proposal to search for a permanent electric dipole moment (EDM) of the muon and put it into the more general context of other EDM searches. These experiments, along with searches for the lepton flavor violating decays $μ\to e γ$ and $μ^- + A \to e^- + A$, provide a path to the high-energy frontier through precision measurements.
description: 9 pages, 8 figures, invited talk at the High Intensity Frontier Workshop 2004, Isola d'Elba
Additional file 3 of Establishing the efficacy of interventions to improve health literacy and health behaviours: a systematic review
Creators: name: Walters, Ronie
name: Leslie, Stephen J.
name: Polson, Rob
name: Cusack, Tara
name: Gorely, Trish
Publisher: name: figshare
Year: 2020
Subjects: subject: Medicine
subject: 59999 Environmental Sciences not elsewhere classified
subject: FOS: Earth and related environmental sciences
subject: Sociology
subject: FOS: Sociology
subject: 69999 Biological Sciences not elsewhere classified
subject: FOS: Biological sciences
subject: Cancer
subject: Science Policy

description: Additional file 3: Supplementary Table 3. Percentage of studies scoring at each reporting grade for the 12 TIDieR items for individual studies, divided into intervention and control conditions.
Proof-of-work consensus by quantum sampling
Creators: name: Singh, Deepesh
name: Muraleedharan, Gopikrishnan
name: Fu, Boxiang
name: Cheng, Chen-Mou
name: Newton, Nicolas Roussy
name: Rohde, Peter P.
name: Brennen, Gavin K.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Quantum Physics (quant-ph)
subject: General Finance (q-fin.GN)
subject: FOS: Physical sciences
subject: FOS: Economics and business

description: Since its advent in 2011, boson sampling has been a preferred candidate for demonstrating quantum advantage because of its simplicity and near-term requirements compared to other quantum algorithms. We propose to use a variant, called coarse-grained boson-sampling (CGBS), as a quantum Proof-of-Work (PoW) scheme for blockchain consensus. The users perform boson sampling using input states that depend on the current block information and commit their samples to the network. Afterwards, CGBS strategies are determined which can be used to both validate samples and reward successful miners. By combining rewards for miners committing honest samples together with penalties for miners committing dishonest samples, a Nash equilibrium is found that incentivizes honest nodes. We provide numerical evidence that these validation tests are hard to spoof classically without knowing the binning scheme ahead of time and show the robustness of our protocol to small partial distinguishability of photons. The scheme works for both Fock state boson sampling and Gaussian boson sampling and provides dramatic speedup and energy savings relative to computation by classical hardware.
description: 24 pages, 7 figures, 1 table (v3 Add more numerical simulation results)
Pressure of the Standard Model at High Temperatures
Creators: name: Gynther, A.
name: Vepsalainen, M.
Publisher: name: arXiv
Year: 2005
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We compute the pressure of the standard model at high temperatures in the symmetric phase to three loops, or to O(g^5) in all coupling constants. We find that the terms of the perturbative expansion in the SU(2) + Higgs sector decrease monotonically with increasing order, but the large values of the strong coupling constant g_s and the Yukawa coupling of the top quark g_Y make the expansion in the full theory converge more slowly. The final result is observed to be about 10% smaller than the ideal gas pressure commonly used in cosmological calculations.
description: 30 pages, 4 figures. v2: one reference added, minor revisions, accepted for publication in JHEP
DEFINING SMALL-SCALE FARMERS IN THE SOUTH AFRICAN CONTEXT
Creators: name: Kirsten, Johann F.
name: Van Zyl, Johan
name: Kirsten, Johann F.
name: Van Zyl, Johan
Publisher: name: Unknown
Year: 1998
Subjects: Farm Management

description: South African agriculture is comprised of mainly two categories of farmers -- the subsistence farmers in the former homeland areas and the large-scale commercial (mainly white) farmers. This is in contrast with the situation in many other countries in the world where one would find a whole range of farm sizes, ranging from the very small or subsistence farmer to the very large farmer/agribusiness. The paper highlights the situation of small-scale farmers in an international context and compares it with the South African situation that is totally different. Within this context, this paper has as basic premise that in South Africa the concept of "small-scale farmer" is usually value-laden, creates wrong impressions and is often viewed in a negative light. "Small-scale" is often equated with a backward, nonproductive, non-commercial, subsistence agriculture that we find in parts of the former homeland areas. This paper endeavours to correct the negative perceptions towards smallscale farms by redefining the small-scale farmer and laying to rest the fallacy that small relates to land size only.
Effective Hamiltonian for Non-Leptonic |Delta F| = 1 Decays at NNLO in QCD
Creators: name: Gorbahn, Martin
name: Haisch, Ulrich
Publisher: name: arXiv
Year: 2004
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We compute the effective hamiltonian for non-leptonic |Delta F| = 1 decays in the standard model including next-to-next-to-leading order QCD corrections. In particular, we present the complete three-loop anomalous dimension matrix describing the mixing of current-current and QCD penguin operators. The calculation is performed in an operator basis which allows to consistently use fully anticommuting gamma_5 in dimensional regularization at an arbitrary number of loops. The renormalization scheme dependences and their cancellation in physical quantities is discussed in detail. Furthermore, we demonstrate how our results are transformed to a different basis of effective operators which is frequently adopted in phenomenological applications. We give all necessary two-loop constant terms which allow to obtain the three-loop anomalous dimensions and the corresponding initial conditions of the two-loop Wilson coefficients in the latter scheme. Finally, we solve the renormalization group equation and give the analytic expressions for the low-energy Wilson coefficients relevant for non-leptonic B meson decays beyond next-to-leading order in both renormalization schemes.
description: 46 pages, 6 figures; typos in Eqs. (27) and (37) corrected (thanks to Guido Bell and Diego Guadagnoli for pointing them out) and numerically irrelevant typos/mistakes in Eqs. (26), (29), (48), (102), and (A.27) corrected (thanks to Xinqiang Li for bringing them to our attention)
String Fragmentation in Supercooled Confinement and implications for Dark Matter
Creators: name: Baldes, Iason
name: Gouttenoire, Yann
name: Sala, Filippo
Publisher: name: Deutsches Elektronen-Synchrotron, DESY, Hamburg
Year: 2021
Subjects: string: fragmentation
dark matter: composite
scale: confinement
dark matter: relic density
deep inelastic scattering
Lorentz
bubble
plasma
flux
confinement

description: A strongly-coupled sector can feature a supercooled confinement transition in the early universe. We point out that, when fundamental quanta of the strong sector are swept into expanding bubbles of the confined phase, the distance between them is large compared to the confinement scale. The flux linking the fundamental quanta then deforms and stretches towards the wall, producing an enhanced number of composite states upon string fragmentation. The composite states are highly boosted in the plasma frame, which leads to additional particle production through the subsequent deep inelastic scattering. We propose a modelling of these dynamics and study the consequences for the abundance and energetics of particles in the universe and for bubble-wall Lorentz factors. This opens several new avenues of investigation, which we begin to explore here, showing that the composite dark matter relic density is affected by many orders of magnitude.
Complex Angular Momenta and the Problem of Exotic States
Creators: name: Azimov, Ya. I.
Publisher: name: arXiv
Year: 2005
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: After some brief personal recollections about V.N.Gribov, I demonstrate that his results and ideas on complex angular momenta may be applied in unfamiliar directions. As an example, it is shown, that any strong interaction amplitude, satisfying dispersion relation (in momentum transfer), has infinite number of energy-plane poles, both for exotic and non-exotic quantum numbers. This result ensures the necessary condition for existence of exotic hadrons. However, without more detailed knowledge of dynamics one cannot secure sufficient conditions for the exotics existence.
description: To appear in the Gribov Memorial Volume (Proceedings of the Gribov-75 Memorial Workshop on Quarks, Hadrons, and Strong Interactions, May 22-24, 2005, Budapest, Hungary
Alignment of Dust in Molecular Clouds
Creators: name: Lazarian, A.
name: Cho, J.
Publisher: name: arXiv
Year: 2004
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Polarimetry is one of the most informative techniques of studying magnetic fields in molecular clouds. How reliable the interpretation of the polarization maps in terms of magnetic fields is the issue that the grain alignment theory addresses. We show that grain alignment involves several processes acting simultaneously, but on different time-scales. We explain that rotating dust grains get substantial magnetic moment that allows them precess fast about magnetic field lines. As the result, grains preserve their orientation to magnetic field when the magnetic field direction fluctuates. We point out to the importance of internal alignment, i.e. the process forces grain axes to be aligned in respect to the grain angular momentum. We show that subtle quantum effects, in particular relaxation related to nuclear magnetic moments of atoms composing the grain, brings to live complex grain motions, e.g. flips. These flips substantially alter the dynamics of grain and limit the applicability of earlier theories that did not account for them. We also briefly review basic physical processes involved in the alignment of grain angular momentum in respect to interstellar magnetic field. We claim that the bulk of existing observational data is consistent with the radiative torque alignment mechanism. In particular, we show that large grains that are known to exist in the cores of molecular clouds may be aligned by the attenuated external interstellar radiation field.
description: 12 pages, Invited Review, Astrophysical Polarimetry 2004, Hawaii, March 15-19, 2004
Photoionized HBeta Emission in NGC 5548: It Breathes!
Creators: name: Cackett, Edward M.
name: Horne, Keith
Publisher: name: arXiv
Year: 2005
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Emission-line regions in active galactic nuclei and other photoionized nebulae should become larger in size when the ionizing luminosity increases. This 'breathing' effect is observed for the Hbeta emission in NGC 5548 by using Hbeta and optical continuum lightcurves from the 13-year 1989-2001 AGN Watch monitoring campaign. To model the breathing, we use two methods to fit the observed lightcurves in detail: (i) parameterized models and, (ii) the MEMECHO reverberation mapping code. Our models assume that optical continuum variations track the ionizing radiation, and that the Hbeta variations respond with time delays due to light travel time. By fitting the data using a delay map that is allowed to change with continuum flux, we find that the strength of the Hbeta response decreases and the time delay increases with ionizing luminosity. The parameterized breathing models allow the time delay and the Hbeta flux to depend on the continuum flux so that, the time delay is proportional to the continuum flux to the power beta, and the Hbeta flux is proportional to the continuum flux to the power alpha. Our fits give 0.1 < beta < 0.46 and 0.57 < alpha < 0.66. alpha is consistent with previous work by Gilbert and Peterson (2003) and Goad, Korista and Knigge (2004). Although we find beta to be flatter than previously determined by Peterson et al. (2002) using cross-correlation methods, it is closer to the predicted values from recent theoretical work by Korista and Goad (2004).
description: 13 pages, 13 figures. Accepted for publication in MNRAS
Generalizing multiple memories from a single drive: The hysteron latch
Creators: name: Lindeman, Chloe W.
name: Jalowiec, Travis R.
name: Keim, Nathan C.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: FOS: Physical sciences

description: Far-from-equilibrium systems can form memories of previous deformations or driving. In systems from sheared glassy materials to buckling beams to crumpled sheets, this behavior is dominated by return-point memory, in which revisiting a past extremum of driving restores the system to a previous state. Cyclic driving with both positive and negative strains forms multiple nested memories -- as in a single-dial combination lock -- while asymmetric driving (only positive strain) cannot. We study this case in a general model of hysteresis that considers discrete elements called hysterons. We show how two hysterons with a frustrated interaction can violate return-point memory, realizing multiple memories of asymmetric driving. This reveals a general principle for designing systems that store sequences of cyclic driving, whether symmetric or asymmetric. In disordered systems, asymmetric driving is a sensitive tool for the direct measurement of frustration.
description: 7 pages, 5 figures
MPEC 2024-A160 : 2022 RY4
Creators: name: Minor Planet Center Staff
Publisher: name: The Minor Planet Center
Year: 2024
Subjects: subject: Small Solar System bodies
valueUri: http://astrothesaurus.org/uat/1469

description: The Minor Planet Electronic Circulars contain information on unusual minor planets, routine data on comets and natural satellites, and occasional editorial announcements.  They are published on behalf of Division F of the International Astronomical Union by the Minor Planet Center, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
Large Steklov eigenvalues via homogenisation on manifolds
Creators: name: Girouard, Alexandre
name: Lagacé, Jean
Publisher: name: arXiv
Year: 2020
Subjects: subject: Spectral Theory (math.SP)
subject: Analysis of PDEs (math.AP)
subject: Differential Geometry (math.DG)
subject: FOS: Mathematics
subject: 35P15 (Primary) 35B27, 58C40, 53A10 (Secondary)

description: Using methods in the spirit of deterministic homogenisation theory we obtain convergence of the Steklov eigenvalues of a sequence of domains in a Riemannian manifold to weighted Laplace eigenvalues of that manifold. The domains are obtained by removing small geodesic balls that are asymptotically densely uniformly distributed as their radius tends to zero. We use this relationship to construct manifolds that have large Steklov eigenvalues. In dimension two, and with constant weight equal to 1, we prove that Kokarev's upper bound of $8π$ for the first nonzero normalised Steklov eigenvalue on orientable surfaces of genus 0 is saturated. For other topological types and eigenvalue indices, we also obtain lower bounds on the best upper bound for the eigenvalue in terms of Laplace maximisers. For the first two eigenvalues, these lower bounds become equalities. A surprising consequence is the existence of free boundary minimal surfaces immersed in the unit ball by first Steklov eigenfunctions and with area strictly larger than $2π$. This was previously thought to be impossible. We provide numerical evidence that some of the already known examples of free boundary minimal surfaces have these properties and also exhibit simulations of new free boundary minimal surfaces of genus 0 in the unit ball with even larger area. The first nonzero Steklov eigenvalue of all these examples is equal to 1, as a consequence of their symmetries and topology, so that they verify a general conjecture by Fraser and Li. In dimension three and larger, we prove that the isoperimetric inequality of Colbois--El Soufi--Girouard is sharp and implies an upper bound for weighted Laplace eigenvalues. We also show that in any manifold with a fixed metric, one can construct by varying the weight a domain with connected boundary whose first nonzero normalised Steklov eigenvalue is arbitrarily large.
description: 30 pages, 5 figures, 1 table
Hostis humani generis : piracy, terrorism and a new international law
Creators: name: Burgess, Douglas Richard
Publisher: name: University of British Columbia
Year: 2009

description: In order to facilitate the pursuit and prosecution of terrorists worldwide, and to ensure upon capture that they receive equitable treatment under the law, a new international law of terrorism must be created. This law must provide a universal definition of terrorism, include a list of terrorist offences, offer guidelines for international pursuit and capture by states, and give the parameters of domestic and international jurisdiction. This thesis argues that the crime of terrorism be based on the existing international crime of piracy, most particularly with regard to pirates' definition as hostis humani generis, enemies of the human race. Such definition would also allow universal jurisdiction over terrorist crimes, as well as distinguishing terrorists as international criminals from legitimate, politically-motivated persons such as insurgents and revolutionaries, and from crimes committed by the state itself. Moreover, this thesis demonstrates that piracy and terrorism are not separate crimes under the law, but inextricably bound in both legal and historical precedent. A recognition of terrorism as a crime of piracy not only has felicitous effects in determining future prosecutions, it also gives terrorism its correct definition in international law.
INDIRECT EFFECTS OF DIFFERENT AGRICULTURAL TRADE SCENARIOS: A SOUTH AFRICAN CASE STUDY
Creators: name: Jooste, Andre
name: Aliber, Michael
name: Van Schalkwyk, Herman D.
name: Jooste, Andre
name: Aliber, Michael
name: Van Schalkwyk, Herman D.
Publisher: name: Unknown
Year: 1998
Subjects: International Relations/Trade

description: One of the most important policy measures used by government to influence agricultural production and trade patterns are tariffs. A substantial depreciation in the exchange rate will not be enough to compensate for the negative effects of removing tariffs if the playing field is not level for producers in South Africa. Although the import multiplier show that less inputs will be imported, this saving on foreign exchange is not big enough to outweigh the total impact of imports on the balance of trade. The value-added multiplier clearly indicate that reinvestment and consumer spending (buying power) in agriculture will receive a severe blow. Employment will be reduced, thus increasing the supply of labour into other sectors.
The South Pole Telescope
Creators: name: SPT Collaboration
name: Ruhl, J. E.
name: Ade, P. A. R.
name: Carlstrom, J. E.
name: Cho, H. M.
name: Crawford, T.
name: Dobbs, M.
name: Greer, C. H.
name: Halverson, N. W.
name: Holzapfel, W. L.
name: Lantin, T. M.
name: Lee, A. T.
name: Leong, J.
name: Leitch, E. M.
name: Lu, W.
name: Lueker, M.
name: Mehl, J.
name: Meyer, S. S.
name: Mohr, J. J.
name: Padin, S.
name: Plagge, T.
name: Pryke, C.
name: Schwan, D.
name: Sharp, M. K.
name: Runyan, M. C.
name: Spieler, H.
name: Staniszewski, Z.
name: Stark, A. A.
Publisher: name: arXiv
Year: 2004
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: A new 10 meter diameter telescope is being constructed for deployment at the NSF South Pole research station. The telescope is designed for conducting large-area millimeter and sub-millimeter wave surveys of faint, low contrast emission, as required to map primary and secondary anisotropies in the cosmic microwave background. To achieve the required sensitivity and resolution, the telescope design employs an off-axis primary with a 10m diameter clear aperture. The full aperture and the associated optics will have a combined surface accuracy of better than 20 microns rms to allow precision operation in the submillimeter atmospheric windows. The telescope will be surrounded with a large reflecting ground screen to reduce sensitivity to thermal emission from the ground and local interference. The optics of the telescope will support a square degree field of view at 2mm wavelength and will feed a new 1000-element micro-lithographed planar bolometric array with superconducting transition-edge sensors and frequency-multiplexed readouts. The first key project will be to conduct a survey over approximately 4000 degrees for galaxy clusters using the Sunyaev-Zel'dovich Effect. This survey should find many thousands of clusters with a mass selection criteria that is remarkably uniform with redshift. Armed with redshifts obtained from optical and infrared follow-up observations, it is expected that the survey will enable significant constraints to be placed on the equation of state of the dark energy.
description: Written prior to SPIE conference, June 21-25, 2004. 19 pages, 13 figures. Also available (with higher resolution figures) at http://spt.uchicago.edu/
EVALUATING SUPPORT TO AGRICULTURE IN SOUTH AFRICA: THE CALCULATION OF NET PROTECTION COEFFICIENTS (NPCS)
Creators: name: Jooste, Andre
name: Van Zyl, Johan
name: Jooste, Andre
name: Van Zyl, Johan
Publisher: name: Unknown
Year: 1998
Subjects: Agricultural and Food Policy

description: The Effective Protection Ratio (EPR) is used in this study as a measure of the impact of policy distortions on agricultural producers. The results of the EPR analysis show that in 1995, most of the interventions supporting agricultural production have disappeared, particularly if the production is aimed at the domestic market. This holds for basic grains and oilseeds, as well as other products such as potatoes, cotton and tobacco, across all regions. Beef cattle and sheep production is also not being favoured by support in any of the regions. On the contrary, a number of commodities are effectively being taxed.
FYNBOS EXPORTS FROM THE WESTERN CAPE PROVINCE: A PROBLEM OF LOGISTICS
Creators: name: Allerts, S.
name: Kleynhans, Theo E.
name: Vink, Nick
name: Allerts, S.
name: Kleynhans, Theo E.
name: Vink, Nick
Publisher: name: Unknown
Year: 1998
Subjects: International Relations/Trade

description: During 1997 research was conducted on trends in factors that affect the supply and demand for airfreight space for fynbos exports from South Africa. The aim was to sensitise decision-makers to probable trends in those factors that will shape cargo space availability. The main finding was that the supply of airfreight to South African producers is aggravated by the unbalanced availability of cargo space on southbound and northbound trips originating from Cape Town. If the price and quantity of cargo space were determined by supply and demand, an imbalance couldn’t arise in a perfect market, as prices would balance cargo space supplied and demanded. However, airfreight tariffs are rigid per weight level. The result is that items with a higher mass per volume unit represent a higher income per palette, and are therefore preferred by export agents. This finding has implications for future growth in the industry.
THE FUTURE OF WILDFLOWER RESEARCH AND DEVELOPMENT IN SOUTH AFRICA - THE LACHENALIA CASE STUDY
Creators: name: Marasas, C.N.
name: Anandajayasekeram, Ponniah
name: Niederwieser, J.G.
name: Coetzee, M.
name: Martella, David R.
name: Pieterse, B.J.
name: Van Rooyen, C.J.
name: Marasas, C.N.
name: Anandajayasekeram, Ponniah
name: Niederwieser, J.G.
name: Coetzee, M.
name: Martella, David R.
name: Pieterse, B.J.
name: Van Rooyen, C.J.
Publisher: name: Unknown
Year: 1998
Subjects: Crop Production/Industries
Research and Development/Tech Change/Emerging Technologies

description: This paper reports the socio-economic impact of the lachenalia research program of the ARCRoodeplaat Vegetable and Ornamental Plant Institute (ARC-Roodeplaat) over the period 1965-2010. Data were collected from researchers, the local propagator and the market agent in Holland, using guidelines and questionnaires. A financial and economic analysis were conducted. The results of both were negative, unless increased productivity, early entry into all potential markets and a decreased research gestation period were assumed. Additional impacts were qualitatively assessed. The program contributed to employment creation, the preservation of biodiversity, capacity building and beneficial institutional linkages. The management information generated by the study was used in planning and priority setting at the institute.