cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Empirical Models for the Realistic Generation of Cooperative Awareness Messages in Vehicular Networks
Creators: name: Molina-Masegosa, Rafael
name: Sepulcre, Miguel
name: Gozalvez, Javier
name: Berens, Friedbert
name: Martinez, Vincent
Publisher: name: arXiv
Year: 2020
Subjects: subject: Networking and Internet Architecture (cs.NI)
subject: FOS: Computer and information sciences

description: Most V2X (Vehicle-to-Everything) applications rely on broadcasting awareness messages known as CAM (Cooperative Awareness Messages) in ETSI or BSM (Basic Safety Message) in SAE standards. A large number of studies have been devoted to guarantee their reliable transmission. However, to date, the studies are generally based on simplified data traffic models that generate awareness messages at periodic intervals or with a constant message size. These models do not accurately represent the real generation of CAM messages that follow specific mobility-based rules. Using simplified and unrealistic traffic models can significantly impact the results and validity of the studies, and hence accurate models for the generation of awareness messages are necessary. This paper proposes the first set of models that can realistically generate CAM messages. The models have been created from real traces collected by two car manufacturers in urban, sub-urban and highway test drives. The models are based on mth order Markov sources, and model the size of CAMs and the time interval between CAMs. The models are openly provided to the community and can be easily integrated into any simulator.
Rigorous analysis of extremely asymmetrical scattering of electromagnetic waves in slanted periodic gratings
Creators: name: Nieminen, T. A.
name: Gramotnev, D. K.
Publisher: name: arXiv
Year: 2005
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: Extremely asymmetrical scattering (EAS) is a new type of Bragg scattering in thick, slanted, periodic gratings. It is realised when the scattered wave propagates parallel to the front boundary of the grating. Its most important feature is the strong resonant increase in the scattered wave amplitude compared to the amplitude of the incident wave: the smaller the grating amplitude, the larger the amplitude of the scattered wave. In this paper, rigorous numerical analysis of EAS is carried out by means of the enhanced T-matrix algorithm. This includes investigation of harmonic generation inside and outside the grating, unusually strong edge effects, fast oscillations of the incident wave amplitude in the grating, etc. Comparison with the previously developed approximate theory is carried out. In particular, it is demonstrated that the applicability conditions for the two-wave approximation in the case of EAS are noticeably more restrictive than those for the conventional Bragg scattering. At the same time, it is shown that the approximate theory is usually highly accurate in terms of description of EAS in the most interesting cases of scattering with strong resonant increase of the scattered wave amplitude. Physical explanation of the predicted effects is presented.
description: 14 pages, 7 figures; v2: corrections to metadata and bibliographical info in preprint
Thermodynamics of the 1+1-dimensional nonlinear sigma model through next-to-leading order in 1/N
Creators: name: Warringa, Harmen J.
Publisher: name: arXiv
Year: 2004
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We discuss the thermodynamics of the O(N) nonlinear sigma model in 1+1 dimensions. In particular we investigate the NLO 1/N correction to the 1PI finite temperature effective potential expressed in terms of an auxiliary field. The effective potential contains temperature-dependent divergences which cannot be renormalized properly. We argue that this problem vanishes at the minimum of the effective potential. Therefore physical quantities like the pressure are well defined and can be renormalized in a temperature-independent way. We give a general argument for the occurrence of temperature-dependent divergences outside the minimum. We present calculations of the pressure and show that 1/N is a good expansion. It turns out that the pressure normalized to that at infinite temperature is N-independent like the flavor independence of the same quantity in QCD.
description: 5 pages, 2 figures. Talk given at the 6th conference on Strong and Electroweak Matter 2004, Helsinki, Finland, 16-19 Jun 2004
Additional file 2 of Establishment of a serological molecular model for the early diagnosis and progression monitoring of bone metastasis in lung cancer
Creators: name: Xiaoyan Teng
name: Lirong Wei
name: Liming Han
name: Daliu Min
name: Yuzhen Du
Publisher: name: figshare
Year: 2020
Subjects: subject: Biochemistry
subject: Medicine
subject: Genetics
subject: FOS: Biological sciences
subject: Biotechnology
subject: 69999 Biological Sciences not elsewhere classified
subject: 19999 Mathematical Sciences not elsewhere classified
subject: FOS: Mathematics
subject: Cancer
subject: Plant Biology

description: Additional file 2: Supplementary Table 2. The basic information of 44 lung cancer patients for prospective validation analysis.
Estudios críticos sobre los personajes de La ciudad y los perros
Creators: name: Delgado Del Aguila, Jesús Miguel
Publisher: name: figshare
Year: 2021
Subjects: subject: 200514 Literature in Spanish and Portuguese
subject: FOS: Languages and literature

description: Delgado Del Aguila, Jesús Miguel (2021). «Estudios críticos sobre los personajes de La ciudad y los perros», en: VaLittera. Revista Literária dos Acadêmicos de Letras. Universidade Estadual de Mato Grosso do Sul, Brasil. Vol. 1, n.° 4, pp. 184-206. Disponible en https://periodicosonline.uems.br/index.php/valit/article/view/6817
Improved current density and magnetisation reconstruction through vector magnetic field measurements
Creators: name: Broadway, D. A.
name: Lillie, S. E.
name: Scholten, Sam C.
name: Rohner, D.
name: Dontschuk, N.
name: Maletinsky, P.
name: Tetienne, J. -P.
name: Hollenberg, L. C. L.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Applied Physics (physics.app-ph)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Materials Science (cond-mat.mtrl-sci)
subject: Computational Physics (physics.comp-ph)
subject: Data Analysis, Statistics and Probability (physics.data-an)
subject: FOS: Physical sciences

description: Stray magnetic fields contain significant information about the electronic and magnetic properties of condensed matter systems. For two-dimensional (2D) systems, stray field measurements can even allow full determination of the source quantity. For instance, a 2D map of the stray magnetic field can be uniquely transformed into the 2D current density that gave rise to the field and, under some conditions, into the equivalent 2D magnetisation. However, implementing these transformations typically requires truncation of the initial data and involves singularities that may introduce errors, artefacts, and amplify noise. Here we investigate the possibility of mitigating these issues through vector measurements. For each scenario (current reconstruction and magnetisation reconstruction) the different possible reconstruction pathways are analysed and their performances compared. In particular, we find that the simultaneous measurement of both in-plane components ($B_x$ and $B_y$) enables near-ideal reconstruction of the current density, without singularity or truncation artefacts, which constitutes a significant improvement over reconstruction based on a single component (e.g. $B_z$). On the other hand, for magnetisation reconstruction, a single measurement of the out-of-plane field ($B_z$) is generally the best choice, regardless of the magnetisation direction. We verify these findings experimentally using nitrogen-vacancy magnetometry in the case of a 2D current density and a 2D magnet with perpendicular magnetisation.
description: 14 pages, 8 figures
HybNet: A Hybrid Deep Learning -- Matched Filter Approach for IoT Signal Detection
Creators: name: Dakic, Kosta
name: Homssi, Bassel Al
name: Lech, Margaret
name: Al-Hourani, Akram
Publisher: name: arXiv
Year: 2021
Subjects: subject: Information Theory (cs.IT)
subject: Signal Processing (eess.SP)
subject: FOS: Computer and information sciences
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: Random access schemes are widely used in IoT wireless access networks to accommodate simplicity and power consumption constraints. As a result, the interference arising from overlapping IoT transmissions is a significant issue in such networks. Traditional signal detection methods are based on the well-established matched filter using the complex conjugate of the signal, which is proven as the optimal filter under additive white Gaussian noise. However, with the colored interference arising from the overlapping IoT transmissions, deep learning approaches are being considered as a better alternative. In this paper, we present a hybrid framework, HybNet, that switches between deep learning and match filter pathways based on the detected interference level. This helps the detector work in a broader range of conditions, optimally leveraging the matched filter and deep learning robustness. We compare the performance of several possible data modalities and detection architectures concerning the interference-to-noise ratio, demonstrating that the proposed HybNet surpasses the complex conjugate matched filter performance under interference-limited scenarios.
Extrasolar planets and brown dwarfs around A-F type stars. I. Performances of radial velocity measurements, first analyses of variations
Creators: name: Galland, F.
name: Lagrange, A. M.
name: Udry, S.
name: Chelli, A.
name: Pepe, F.
name: Queloz, D.
name: Beuzit, J. L.
name: Mayor, M.
Publisher: name: arXiv
Year: 2005
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We present the performances of a radial velocity measurement method that we developed for A-F type stars. These perfomances are evaluated through an extensive set of simulations, together with actual radial velocity observations of such stars using the ELODIE and HARPS spectrographs. We report the case of stars constant in radial velocity, the example of a binary detection on HD 48097 (an A2V star, with vsini equal to 90 km/s) and a confirmation of the existence of a 3.9 MJup planet orbiting around HD 120136 (Tau Boo). The instability strip problem is also discussed. We show that with this method, it is in principle possible to detect planets and brown dwarfs around A-F type stars, thus allowing further study of the impact of stellar masses on planetary system formation over a wider range of stellar masses than is currently done.
description: final version, accepted for publication (A&A)
Support for pro-poor agricultural development and rural poverty reduction in Eastern Cape
Creators: name: Dzivakwi, Robert
name: Jacobs, Peter T.
name: Dzivakwi, Robert
name: Jacobs, Peter T.
Publisher: name: Unknown
Year: 2010
Subjects: International Development

description: Official data show that a small proportion of Eastern Cape households evidently derive their main or primary income from farming. But the same data also show that the majority of households with access to small plots suitable for farming are concentrated in Eastern Cape. Furthermore, comparative analyses of standard indicators of human wellbeing and development of Eastern Cape with the rest of South Africa show that the province consistently reports worse than national average rates of poverty, food insecurity, unemployment and inequality- reaching extreme levels in rural locations. Over the medium term, higher economic growth and service-oriented sectoral change, might be inadequate to reverse this dismal track record in human well-being. In this context, this paper considers the potential of better targeted public spending on agricultural development for resource-poor small farmers to raise living standards in the Eastern Cape. According to the latest official evidence, slightly more than half a million households in Eastern Cape (representing roughly 40% of all South African households) reported that they have access to farmland- with average land size in the order of 1-1.25 ha per farmily. Interventions aimed at boosting agricultural productivity among these small producers, such as the CASP launched in 2004/05, must be better targeted to meet the needs of the intended beneficiaries.
Modelling of membrane enhanced biological phosphorus removal : determining model parameters
Creators: name: Zhang, Zhe
Publisher: name: University of British Columbia
Year: 2009

description: Parameter determination and wastewater characterization are crucial for modeling of the membrane enhanced biological phosphorus removal process (MEBPR). The batch test is a preferred approach for assessing the model components. Sludge samples from an MEBPR and a simplified University of Cape Town, South Africa (UCT) processes were analyzed in parallel to estimate the growth yield, decay rate and maximum specific growth rate of the heterotrophic biomass, in addition to investigating the difference between the two processes in terms of the microbial activity, by comparing the growth yield, decay coefficient and maximum specific growth rate of the heterotrophic biomass. Methods reported in the literature were used in this study. Carbon, nitrogen and phosphorus fractions of influent wastewater at the UBC pilot plant were characterized to provide the basic information prior to computer simulation. This study presents and discusses results of parameter estimation and wastewater characterization from available data. A slightly lower growth yield value was observed in the MEBPR process compared with the simplified UCT process. The model decay coefficient results based on the two processes were very close. However, different values of maximum specific growth rate of heterotrophic biomass were found between the MEBPR and the simplified UCT processes. The concentrations of readily biodegradable substrate and fermentation products were in the typical range; and the ratios of COD/TKN and COD/TP in the wastewater would allow for excellent nitrogen and phosphorus removal in the MEBPR process; while the higher fractions of inert particulate matter and slowly biodegradable substrates in the wastewater may affect the performance of the MEBPR process. The experimental results suggested that characterization is very important for modeling the membrane enhanced biological phosphorus removal process, and the parameters that are wastewater-specific must be determined for the use of modeling. More studies on the shear force, mass transfer, and mixing conditions in the MEBPR process should be conducted to investigate their effects on microbial activities.
A Discrete Ion Stochastic Continuum Overdamped Solvent Algorithm for Modeling Electrolytes
Creators: name: Ladiges, Daniel R.
name: Carney, Sean P.
name: Nonaka, Andrew
name: Klymko, Katherine
name: Moore, Guy C.
name: Garcia, Alejandro L.
name: Natesh, Sachin R.
name: Donev, Aleksandar
name: Bell, John B.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Computational Physics (physics.comp-ph)
subject: Chemical Physics (physics.chem-ph)
subject: Fluid Dynamics (physics.flu-dyn)
subject: FOS: Physical sciences

description: In this paper we develop a methodology for the mesoscale simulation of strong electrolytes. The methodology is an extension of the Fluctuating Immersed Boundary (FIB) approach that treats a solute as discrete Lagrangian particles that interact with Eulerian hydrodynamic and electrostatic fields. In both cases the Immersed Boundary (IB) method of Peskin is used for particle-field coupling. Hydrodynamic interactions are taken to be overdamped, with thermal noise incorporated using the fluctuating Stokes equation, including a "dry diffusion" Brownian motion to account for scales not resolved by the coarse-grained model of the solvent. Long range electrostatic interactions are computed by solving the Poisson equation, with short range corrections included using a novel immersed-boundary variant of the classical Particle-Particle Particle-Mesh (P3M) technique. Also included is a short range repulsive force based on the Weeks-Chandler-Andersen (WCA) potential. The new methodology is validated by comparison to Debye-H{ü}ckel theory for ion-ion pair correlation functions, and Debye-H{ü}ckel-Onsager theory for conductivity, including the Wein effect for strong electric fields. In each case good agreement is observed, provided that hydrodynamic interactions at the typical ion-ion separation are resolved by the fluid grid.
description: 30 pages, 12 figures, 2 tables
Response of buried polyethylene natural gas pipelines subjected to lateral ground displacement
Creators: name: Anderson, Christopher D.
Publisher: name: University of British Columbia
Year: 2009

description: Permanent ground deformations (PGD) are a major cause o f damage to buried natural gas pipeline systems, particularly in areas of ongoing ground deformation. A new testing apparatus was designed and constructed specifically to meet the requirements of full-scale physical modeling research on typical polyethylene natural gas pipeline configurations subjected to lateral ground displacements. The apparatus essentially comprised a large soil testing chamber in which pipeline configurations could be monitored with an instrumentation array measuring pullout resistance, pipeline displacement, and local strain within the pipe specimens. Specialized methods were developed for mounting strain gauges to polyethylene to obtain reliable readings, and to reduce imposed drag forces. A series of tests performed on straight pipeline sections indicated that peak axial pullout resistance predicted using published design equations tended to over-predict pullout resistance of polyethylene pipes in uncompacted sand, and to underestimate pullout resistance in dense sand. Significant limitations were found in the applicability of current design equations, developed from tests on rigid steel pipelines, to the prediction of axial pullout resistance of relatively "flexible" polyethylene pipelines. Several soil-pipeline interaction mechanisms have been suggested that seem to account for the observed differences in behaviour between polyethylene and steel pipelines. Axial tests on trunk lines with tee connections to smaller size branch pipes indicated that branched configurations experience a complex interaction with the soil. The branch pipe initially deflected and elongated in close proximity to the tee connection, then with increasing displacement, pipe deformation transitioned to axial pullout of the branch. The contribution to pullout resistance from the branches was similar in both uncompacted and dense sand, and also was not significantly affected by the diameter of the trunk line. The anchoring effect of the branch pipe generates significant strain concentrations in both trunk line and branch pipes. In relatively large diameter (115 mm) trunk lines, the highest vulnerability to such strain concentrations was in the smaller diameter (15 mm) branched pipe. In small diameter (60 mm) trunk lines these strain concentrations were observed to induce yielding of the trunk line.
Quantum Phases of the Extended Bose-Hubbard Hamiltonian: Possibility of a Supersolid State of Cold Atoms in Optical Lattices
Creators: name: Scarola, V. W.
name: Sarma, S. Das
Publisher: name: arXiv
Year: 2005
Subjects: subject: Other Condensed Matter (cond-mat.other)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Cold atom optical lattices typically simulate zero-range Hubbard models. We discuss the theoretical possibility of using excited states of optical lattices to generate extended range Hubbard models. We find that bosons confined to higher bands of optical lattices allow for a rich phase diagram, including the supersolid phase. Using Gutzwiller, mean field theory we establish the parameter regime necessary to maintain metastable states generated by an extended Bose-Hubbard model.
description: 5 pages, 3 figures Refernces Added
Does respondent’s perceived knowledge of the status quo affect attribute attendance and WTP in choice experiments? Evidence from the Karapiro Catchment Freshwater streams
Creators: name: Marsh, Dan
name: Mkwara, Lena Asimenye
name: Scarpa, Riccardo
name: Marsh, Dan
name: Mkwara, Lena Asimenye
name: Scarpa, Riccardo
Publisher: name: Unknown
Year: 2010
Subjects: subject: Community/Rural/Urban Development
subject: Environmental Economics and Policy
subject: Health Economics and Policy
subject: Land Economics/Use
subject: Choice experiments
subject: Fixed status quo
subject: People’s perceived status quo
subject: Willingness to pay.

description: In environmental valuation studies with stated preference methods researchers often provide descriptions of status quo conditions which may differ from those perceived by respondents. Ignoring this difference in utility baselines may affect the way attributes are attended to in choice tasks and further affect the magnitude of utility changes and hence bias the implied estimates of benefits from the proposed environmental policies. We investigate this issue using data from a choice experiment on a community’s willingness to pay for water quality improvements in streams. About 60% of respondents perceived the description of the quality of water in streams to be better than the one we provided in our scenario. Our results show some differences in serial attribute non-attendance between respondents who were provided with our baseline description of the status quo and those who used their own perceived baselines. The results further reveal some differences in attribute non-attendance in the two split samples within respondents who used their own descriptions of the status quo conditions. Generally we note that non-attendance to cost was higher in respondents who reported lower levels of water quality than those who perceived water quality to be higher. However, we find mixed results in terms of the willingness to pay for water quality improvements.
The prompt X-ray emission of GRB011211: possible evidence of a transient absorption feature
Creators: name: Frontera, F.
name: Amati, L.
name: Zand, J. J. M. in 't
name: Lazzati, D.
name: Konigl, A.
name: Vietri, M.
name: Costa, E.
name: Feroci, M.
name: Guidorzi, C.
name: Montanari, E.
name: Orlandini, M.
name: Pian, E.
name: Piro, L.
Publisher: name: arXiv
Year: 2004
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We report on observation results of the prompt X- and gamma-ray emission from GRB011211. This event was detected with the Gamma-Ray Burst Monitor and one of the Wide Field Cameras aboard the BeppoSAX satellite. The optical counterpart to the GRB was soon identified and its redshift determined (z = 2.140), while with the XMM-Newton satellite, the X-ray afterglow emission was detected. Evidence of soft X-ray emission lines was reported by Reeves et al. (2002), but not confirmed by other authors. In investigating the spectral evolution of the prompt emission we find the possible evidence of a transient absorption feature at 6.9^{+0.6}_{-0.5} keV during the rise of the primary event. The significance of the feature is derived with non parametric tests and numerical simulations, finding a chance probability which ranges from 3x10^{-3} down to 4x10^{-4}. The feature shows a Gaussian profile and an equivalent width of 1.2^{+0.5}_{-0.6} keV. We discuss our results and their possible interpretation.
description: 23 pages, 3 Tables, 6 Figures. Accepted for publication in Astrophysical Journal
Additional file 1 of Fast-track- recovery surgery with a whey-protein-infused carbohydrate-loading drink pre-operatively and early oral feeding post-operatively among surgical gynaecological cancer patients: study protocol of an open-labelled, randomised controlled trial
Creators: name: Chiou Yi Ho
name: Ibrahim, Zuriati
name: Zalina Abu Zaid
name: Zulfitri ‘Azuan Mat Daud
name: Nor Baizura Md Yusop
Publisher: name: figshare
Year: 2020
Subjects: subject: Space Science
subject: Medicine
subject: Neuroscience
subject: Physiology
subject: FOS: Biological sciences
subject: 111714 Mental Health
subject: FOS: Health sciences

description: Additional file 1. Participant information sheet & consent form.
Associativity in multary quasigroups: The way of biased expansions
Creators: name: Zaslavsky, Thomas
Publisher: name: arXiv
Year: 2004
Subjects: subject: Combinatorics (math.CO)
subject: FOS: Mathematics
subject: 05C22, 20N05 (Primary) 05B15, 05B35 (Secondary)

description: A "biased expansion" of a graph is a kind of branched covering graph with additional structure related to combinatorial homotopy of circles. Some but not all biased expansions are constructed from groups ("group expansions"); these include all biased expansions of complete graphs (assuming order at least four), which correspond to Dowling's lattices of a group and encode an iterated group operation. A biased expansion of a circle with chords encodes a multary (polyadic, n-ary) quasigroup, the chords corresponding to factorizations, i.e., associative structure. We show that any biased expansion of a 3-connected graph (of order at least four) is a group expansion, and that all 2-connected biased expansions are constructed by expanded edge amalgamation from group expansions and irreducible multary quasigroups. If a 2-connected biased expansion covers every base edge at most three times, or if every four-node minor is a group expansion, then the whole biased expansion is a group expansion. In particular, if a multary quasigroup has a factorization graph that is 3-connected, if it has order 3, or if every residual ternary quasigroup is an iterated group isotope, it is isotopic to an iterated group. We mention applications to generalizing Dowling geometries and to transversal designs of high strength.
description: 4 figures; 44 pages. Latest version fixes missing citations, most of which I could not identify (and are in Russian), and makes minor edits
No intrinsic decoherence of inflationary cosmological perturbations
Creators: name: Hsiang, Jen-Tsung
name: Hu, Bei-Lok
Publisher: name: arXiv
Year: 2021
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: After a brief summary of decoherence and quantum to classical transition in cosmology we focus on the study of quantum decoherence of cosmological perturbations in inflationary universe, that does not rely on any environment. This is what `intrinsic' in the title refers to -- a closed quantum system. The question is, does its quantum perturbations decohere with an inflationary expansion of the universe. A dominant view which had propagated for a quarter of a century asserts yes, based on the belief that the large squeezing of a quantum state after a duration of inflation renders the system effectively classical. This paper debunks this view by identifying the technical fault-lines in its derivations and revealing the pitfalls in its arguments which drew earlier authors to this wrong conclusion. We use a few simple quantum mechanical models to expound where the fallacy originated: The highly squeezed ellipse quadrature in phase space cannot be simplified to a line, and the Wigner function cannot be replaced by a delta function. These amount to taking only the leading order contributions in seeking the semiclassical limit and ignoring the subdominant contributions where quantum features reside. Doing so violates the bounds of the Wigner function, and its wave functions possess negative eigenvalues. Moreover, the Robertson-Schrodinger uncertainty relation for a pure state is violated. For inflationary cosmological perturbations, in addition to these features, entanglement exists between the created pairs. This uniquely quantum feature cannot be easily argued away. Indeed it could be our best hope to retroduce the quantum nature of cosmological perturbations and the trace of an inflaton field. All this point to the fact that a closed quantum system, even when highly squeezed, evolves unitarily without loss of coherence; quantum cosmological perturbations do not by itself decohere.
description: 55 pages, 5 figures
Trading out of Poverty: WTO Agreements and the West African Agriculture. A Report of the Food Security II Cooperative Agreement
Creators: name: Nouve, Kofi
name: Staatz, John M.
name: Schweikhardt, David B.
name: Yade, Mbaye
name: Nouve, Kofi
name: Staatz, John M.
name: Schweikhardt, David B.
name: Yade, Mbaye
Publisher: name: Unknown
Year: 2002
Subjects: subject: Food Security and Poverty
subject: International Relations/Trade
subject: food security
subject: food policy
subject: world trade organization
subject: poverty
subject: West Africa
subject: international trade
subject: market access

description: This report is a brief survey of WTO agreements and their implications for the West African economies (including Chad). The study reviews the positions of West African countries on various WTO issues and compares these positions with positions expressed by major trade partners, particularly the Cairns Group, the European Union, Japan, Sub-Sahara Africa, and the United States.
Promouvoir les échanges commerciaux pour réduire la pauvreté : les accords de l’ OMC et l’agriculture en Afrique de l’ Ouest. Un rapport de l’ Accord de Coopération no. II sur la sécurité alimentaire
Creators: name: Nouve, Kofi
name: Staatz, John M.
name: Schweikhardt, David B.
name: Yade, Mbaye
name: Nouve, Kofi
name: Staatz, John M.
name: Schweikhardt, David B.
name: Yade, Mbaye
Publisher: name: Unknown
Year: 2002
Subjects: subject: Food Security and Poverty
subject: International Relations/Trade
subject: World Trade Organization
subject: poverty

description: Ce rapport est une vue d’ensemble sommaire des accords commerciaux de l’ OMC et de leurs implications pour les pays de l’ Afrique de l’ Ouest (ainsi que le Tchad). L’étude décrit les positions adoptées par les pays de l’ Afrique de l’ Ouest sur divers enjeux des négociations commerciales de l’ OMC, tout en comparant ces positions avec celles exprimées par les grands partenaires commerciaux, notamment l’ Union Européenne, le Japon, les U.S.A. et le reste de l’ Afrique Subsaharienne.
A note on spherically symmetric naked singularities in general dimension
Creators: name: Langfelder, Peter
name: Mann, Robert B.
Publisher: name: arXiv
Year: 2004
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We discuss generalizations of the recent theorem by Dafermos (hep-th/0403033) forbidding a certain class of naked singularities in the spherical collapse of a scalar field. Employing techniques similar to the ones Dafermos used, we consider extending the theorem (1) to higher dimensions, (2) by including more general matter represented by a stress-energy tensor satisfying certain assumptions, and (3) by replacing the spherical geometry by a toroidal or higher genus (locally hyperbolic) one. We show that the extension to higher dimensions and a more general topology is straightforward; on the other hand, replacing the scalar field by a more general matter content forces us to shrink the class of naked singularities we are able to exclude. We then show that the most common matter theories (scalar field interacting with a non-abelian gauge field and a perfect fluid satisfying certain conditions) obey the assumptions of our weaker theorem, and we end by commenting on the applicability of our results to the five-dimensional AdS scenarii considered recently in the literature.
description: 16 pages, no figures, typos fixed
$\mathbb{Z}_2$-enriched symmetry indicators for topological superconductors in the 1651 magnetic space groups
Creators: name: Ono, Seishiro
name: Po, Hoi Chun
name: Shiozaki, Ken
Publisher: name: arXiv
Year: 2020
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: While the symmetry-based diagnosis of topological insulators and semimetals has enabled large-scale discovery of topological materials candidates, the extension of these approaches to the diagnosis of topological superconductors remains a major open question. One important new ingredient in the analysis of topological superconductivity is the presence of $\mathbb Z_2$-valued Pfaffian invariants associated with certain high-symmetry momenta. Such topological invariants lie beyond the conventional scope of symmetry representation theory for band structures, and as such they are nontrivial to incorporate into the systematic calculations of the symmetry indicators of band topology. Here, we overcome this challenge and report the full computation of the $\mathbb Z_2$-enriched symmetry indicators for superconductors in all symmetry settings. Our results indicate that incorporating the $\mathbb Z_2$ band labels enhance the diagnostic power of the scheme in roughly $60\%$ of the symmetry settings. Our framework can also be readily integrated with first-principles calculations to elucidate on the possible properties of unconventional superconductivity in a given compound. As a demonstration, we analyze explicitly the interplay between pairing symmetry and topological superconductivity in the recently discovered superconductors CaPtAs and CaSb$_2$.
description: (6 + 171) pages
BGG sequences with weak regularity and applications
Creators: name: Čap, Andreas
name: Hu, Kaibo
Publisher: name: arXiv
Year: 2022
Subjects: subject: Numerical Analysis (math.NA)
subject: Analysis of PDEs (math.AP)
subject: Differential Geometry (math.DG)
subject: Functional Analysis (math.FA)
subject: Representation Theory (math.RT)
subject: FOS: Mathematics

description: We investigate some Bernstein-Gelfand-Gelfand (BGG) complexes on bounded Lipschitz domains in $\mathbb{R}^n$ consisting of Sobolev spaces. In particular, we compute the cohomology of the conformal deformation complex and the conformal Hessian complex in the Sobolev setting. The machinery does not require algebraic injectivity/surjectivity conditions between the input spaces, and allows multiple input complexes. As applications, we establish a conformal Korn inequality in two space dimensions with the Cauchy-Riemann operator and an additional third order operator with a background in Möbius geometry. We show that the linear Cosserat elasticity model is a Hodge-Laplacian problem of a twisted de-Rham complex. From this cohomological perspective, we propose potential generalizations of continuum models with microstructures.
Linkages Between Agricultural Growth and Improved Child Nutrition in Mali
Creators: name: Tefft, James F.
name: Penders, Christopher L.
name: Kelly, Valerie A.
name: Staatz, John M.
name: Yade, Mbaye
name: Wise, Victoria
name: Tefft, James F.
name: Penders, Christopher L.
name: Kelly, Valerie A.
name: Staatz, John M.
name: Yade, Mbaye
name: Wise, Victoria
Publisher: name: Unknown
Year: 2000
Subjects: subject: Food Consumption/Nutrition/Food Safety
subject: International Development
subject: food security
subject: food policy
subject: child nutrition
subject: Mali
subject: agricultural growth

description: This paper presents the results of the first phase of a project aimed at analyzing the links between agricultural growth in Mali and child nutritional status. The objective of this project is to strengthen these links through applied research and extension. The first phase of the project was designed to generate hypotheses concerning the relationship and review existing data to test these hypotheses, generate new hypotheses and draw policy implications. The second phase of this project will carry out in-depth research to address the critical questions left unanswered in phase I and initiate actions designed to improve these links.
Presentation: Strengthening The Creative Economy Based on The Potential of Village Resources in The Community Lemahdadi, Bantul, DIY
Creators: name: Sujatmika
name: Harsa Prawignya
name: Nurharianti, Emmy
name: Hartati, Anis Siti
Publisher: name: Zenodo
Year: 2022

description: This material has presented on 1st International Conference on Advance Research in Social and Economic Science. October 25, 2022
Food Markets, Policy, and Technology: The Case of Honduran Dry Beans
Creators: name: Martel, Pedro V.
name: Bernsten, Richard H.
name: Weber, Michael T.
name: Martel, Pedro V.
name: Bernsten, Richard H.
name: Weber, Michael T.
Publisher: name: Unknown
Year: 2000
Subjects: subject: Crop Production/Industries
subject: Marketing
subject: FOS: Economics and business
subject: food security
subject: food policy
subject: dry beans
subject: El Salvador

description: To identify constraints and options to increase bean subsector’s productivity, 239 farmers and 57 city traders were surveyed, and a rapid appraisal of the El Salvadorian market was conducted. Data were analyzed with descriptive statistics, logistic analysis, and linear regression analysis. This research shows that farmers' socioeconomic characteristics, production environments, and institutional factors all affect the varietal adoption process.
Increasing Seed System Efficiency in Africa: Concepts, Strategies and Issues
Creators: name: Maredia, Mywish K.
name: Howard, Julie A.
name: Boughton, Duncan
name: Naseem, Anwar
name: Wanzala, Maria N.
name: Kajisa, Kei
name: Maredia, Mywish K.
name: Howard, Julie A.
name: Boughton, Duncan
name: Naseem, Anwar
name: Wanzala, Maria N.
name: Kajisa, Kei
Publisher: name: Unknown
Year: 1999
Subjects: subject: Crop Production/Industries
subject: food security
subject: food policy
subject: Sub-Saharan Africa
subject: seed system

description: The purpose of this paper is to provide a conceptual framework that can be used by agricultural leaders, administrators, policy makers, and seed program managers to (1) understand key factors affecting seed system development; and (2) compare organizational and institutional strategies for increasing seed system effectiveness. A literature review of recent studies on seed system development in Sub-Saharan Africa (SSA) was undertaken to achieve these objectives. The studies reviewed included published and unpublished reports, monographs, and case studies.
ESKI O'ZBEK YOZUVIDAGI HARF NOMLARINING LEKSIK TIZIM TARKIBIDAGI O'RNI
Creators: name: Sharipova, Mavlyuda
Publisher: name: Zenodo
Year: 2025

description: Maqolada o’zbek tili leksik tizimidagi  otlarning ma’noviy guruhlaridan biri—grafik belgilarni ifodalovchi otlar (grafonimlar) va ularning bir guruhchasi bo’lgan harf nomlari, ya’ni literonimlar o’zbek – arab alifbosidagi alif, lom, mim harflari misolida tahlil etilgan, leksik, semantik va funksional xususiyatlari ko’rsatib o’tilgan, lisoniy tizimdagi o’rni aniqlangan.
Signal model and event reconstruction for the radio detection of inclined air showers
Creators: name: Schlüter, Felix
name: Huege, Tim
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: FOS: Physical sciences

description: The detection of inclined air showers (zenith angles $θ\gtrsim 65^\circ$) with kilometer-spaced radio-antenna arrays allows measuring cosmic rays at ultra-high energies ($E \lesssim 10^{20}\,\mathrm{eV}$). Radio and particle detector arrays provide independent measurements of the electromagnetic and muonic shower components of inclined air showers, respectively. Combined, these measurements have a large sensitivity to discriminate between air showers initiated by lighter and heavier cosmic rays.
 We have developed a precise model of the two-dimensional, highly complex and asymmetric lateral radio-signal distributions of inclined air shower at ground -- the ``radio-emission footprints''. Our model explicitly describes the dominant geomagnetic emission with a rotationally symmetric lateral distribution function, on top of which additional effects disturb the symmetry. The asymmetries are associated with the interference between the geomagnetic and sub-dominant charge-excess emission as well as with geometrical projection effects, so-called ``early-late'' effects. Our fully analytic model describes the entire footprint with only two observables: the geometrical distance between the shower impact point at the ground and the shower maximum $d_\mathrm{max}$, and the geomagnetic radiation energy $E_\mathrm{geo}$. We demonstrate that with this model, the electromagnetic shower energy can be reconstructed by kilometer-spaced antenna arrays with an intrinsic resolution of 5\% and a negligible bias.
description: Published in JCAP. The colours in figures 1, 3, and 7 might not be correctly displayed with certain pdf viewer (Adobe works)
The length and depth of associative algebras
Creators: name: Sercombe, Damian
name: Shalev, Aner
Publisher: name: arXiv
Year: 2020
Subjects: subject: Rings and Algebras (math.RA)
subject: Group Theory (math.GR)
subject: FOS: Mathematics
subject: Primary 20P70, Secondary 20P10

description: Recently there has been considerable interest in studying the length and the depth of finite groups, algebraic groups and Lie groups. In this paper we introduce and study similar notions for algebras. Let $k$ be a field and let $A$ be an associative, not necessarily unital, algebra over $k$. An unrefinable chain of $A$ is a chain of subalgebras $A=A_0>A_1>...>A_t=0$ for some integer $t$ where each $A_i$ is a maximal subalgebra of $A_{i-1}$. The maximal (respectively, minimal) length of such an unrefinable chain is called the length (respectively, depth) of $A$. It turns out that finite length, finite depth and finite dimension are equivalent properties for $A$. For $A$ finite dimensional, we give a formula for the length of $A$, we bound the depth of $A$, and we study when the length of $A$ equals its dimension and its depth respectively. Finally, we investigate under what circumstances the dimension of $A$ is bounded above by a function of its length, or its depth, or its length minus its depth.
description: 18 pages
Topological constraints on stabilized flux vacua
Creators: name: Saulina, Natalia
Publisher: name: arXiv
Year: 2005
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We study the influence of four-form fluxes on the stabilization of the Kahler moduli in M-theory compactified on a Calabi-Yau four-fold. We find that, under certain non-degeneracy condition on the flux, M5-instantons of a new topological type generate a superpotential. The existence of such an instanton restricts possible four-folds for which the stabilization by this mechanism is expected. These topological constraints on the background are different from the previously known constraints, derived from the flux-free analysis of the nonperturbative effects.
description: 10 pages, harvmac, references added
$I=1/2$ $S$-wave and $P$-wave $Kπ$ scattering and the $κ$ and $K^*$ resonances from lattice QCD
Creators: name: Rendon, Gumaro
name: Leskovec, Luka
name: Meinel, Stefan
name: Negele, John
name: Paul, Srijit
name: Petschlies, Marcus
name: Pochinsky, Andrew
name: Silvi, Giorgio
name: Syritsyn, Sergey
Publisher: name: arXiv
Year: 2020
Subjects: subject: High Energy Physics - Lattice (hep-lat)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We present a lattice-QCD determination of the elastic isospin-$1/2$ $S$-wave and $P$-wave $Kπ$ scattering amplitudes as a function of the center-of-mass energy using Lüscher's method. We perform global fits of $K$-matrix parametrizations to the finite-volume energy spectra for all irreducible representations with total momenta up to $\sqrt{3}\frac{2π}{L}$; this includes irreps that mix the $S$- and $P$-waves. Several different parametrizations for the energy dependence of the $K$-matrix are considered. We also determine the positions of the nearest poles in the scattering amplitudes, which correspond to the broad $κ$ resonance in the $S$-wave and the narrow $K^*(892)$ resonance in the $P$-wave. Our calculations are performed with $2+1$ dynamical clover fermions for two different pion masses of $317.2(2.2)$ and $175.9(1.8)$ MeV. Our preferred $S$-wave parametrization is based on a conformal map and includes an Adler zero; for the $P$-wave we use a standard pole parametrization including Blatt-Weisskopf barrier factors. The $S$-wave $κ$-resonance pole positions are found to be $\left[0.86(12) - 0.309(50)\,i\right]\:{\rm GeV}$ at the heavier pion mass and $\left[0.499(55)- 0.379(66)\,i\right]\:{\rm GeV}$ at the lighter pion mass. The $P$-wave $K^*$-resonance pole positions are found to be $\left[ 0.8951(64) - 0.00250(21)\,i \right]\:{\rm GeV}$ at the heavier pion mass and $\left[0.8718(82) - 0.0130(11)\,i\right]\:{\rm GeV}$ at the lighter pion mass, which corresponds to couplings of $g_{K^* Kπ}=5.02(26)$ and $g_{K^* Kπ}=4.99(22)$, respectively.
description: 25 pages, 10 figures
Electromagnetically induced transparency and dynamic Stark effect in coupled quantum resonators
Creators: name: de Ponte, M. A.
name: Villas-Boas, C. J.
name: Serra, R. M.
name: Moussa, M. H. Y.
Publisher: name: arXiv
Year: 2004
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: In this work we reproduce the phenomenology of the electromagnetically induced transparency and dynamic Stark effect in a dissipative system composed by two coupled bosonic fields under linear and nonlinear amplification process. Such a system can be used as a quantum switch in networks of oscillators.
Statistiques Agricoles: Production Agricole, Superficies et Utilisation des terres, Année agricole 2002
Creators: name: Nyarwaya, Jean Baptiste
name: Shingiro, Emmanuel
name: Mpyisi, Edson
name: Nyarwaya, Jean Baptiste
name: Shingiro, Emmanuel
name: Mpyisi, Edson
Publisher: name: Unknown
Year: 2002
Subjects: subject: Farm Management
subject: food security
subject: food policy
subject: Rwanda
subject: statistics

description: Food Security Research Project (FSRP) et Division des Statistiques Agricoles (DSA) Ministère de l’Agricuture, de l’Elevage et des Forêts, MINAGRI
Particle monolayer assembly in evaporating salty colloidal droplets
Creators: name: Bruning, M. A.
name: Loeffen, L.
name: Marin, A.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: Ring-shaped deposits can be often found after a droplet evaporates on a substrate. If the fluid in the droplet is a pure liquid and its contact line remains pinned during the process, the mechanism behind such ring-shaped deposition is the well-known coffee-stain effect. However, adding small amounts of salt to such a droplet can change the internal flow dramatically and consequently change the deposition mechanism. Due to an increase of surface tension in the contact line region, a Marangoni flow arises which is directed from the apex of the droplet towards the contact line. As a result, particles arrive at the contact line following the liquid-air interface of the droplet. Interestingly, the deposit is also ring-shaped, as in the classical coffee-stain effect, but with a radically different morphology: particles form a monolayer along the liquid-air interface of the droplet, instead of a compact three-dimensional deposit. Using confocal microscopy, we study particle-per-particle how the assembly of the colloidal monolayer occurs during the evaporation of droplets for different initial concentration of sodium chloride and initial particle dilution. Our results are compared with classical diffusion-limited deposition models and open up an interesting scenario of deposits via interfacial particle assembly, which can easily yield homogeneous depositions by manipulating the initial salt and particle concentration in the droplet.
description: 15 pages, 12 figures