cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Przemysł spożywczy krajów Unii Europejskiej w latach kryzysu gospodarczego 2007-2011
Creators: name: Żelazowska-Przewłoka, Anna
name: Żelazowska-Przewłoka, Anna
Publisher: name: Unknown
Year: 2013
Subjects: subject: Agribusiness
subject: Agricultural and Food Policy
subject: Industrial Organization
subject: International Relations/Trade
subject: economic crisis
subject: food industry
subject: European Union
subject: / kryzys gospodarczy
subject: przemysł spożywczy
subject: Unia Europejska

description: The purpose of this study was to present changes in the food industry in the countries of the European Union in the years of economic crisis, 2007-2011. On the basis of the data from the European Commission web pages and from the bulletin “Data & trends of the European Food and Drink Industry”, the size of the food industry in general and in the countries of the European Union was analyzed. It was found that despite the economic crisis, these changes were rather small. / Synopsis. Celem opracowania było przedstawienie zmian w przemyśle spożywczym w krajach Unii Europejskiej w latach kryzysu gospodarczego 2007-2011. Na podstawie danych zawartych na stronach Komisji Europejskiej i w biuletynach Data & trends of the European Food and Drink Industry przeanalizowano wielkości przemysłu spożywczego ogółem oraz w krajach Unii Europejskiej. Stwierdzono, że mimo kryzysu gospodarczego zmiany te były niewielkie.
EVOLUÇÃO DA QUALIDADE DO EMPREGO NA AGROPECUÁRIA BRASILEIRA: UMA AVALIAÇÃO DO PERÍODO 1990 - 2010
Creators: name: Rodrigues, Camila Pereira Brígido
name: Santos, José Márcio Dos
name: Rodrigues, Camila Pereira Brígido
name: Santos, José Márcio Dos
Publisher: name: Unknown
Year: 2013
Subjects: subject: Agribusiness
subject: Labor and Human Capital
subject: Employment quality
subject: Agriculture and cattle raising sectors
subject: Regional economy

description: The rural segments are going through intense changes in their scenarios. Brazilian agriculture and cattle raising sectors, due to exports and production growth for the domestic market, contribute to job growth. However, due to technological changes and advancement of the urbanization, a change in the dynamics of labor in this sector has occurred, modifying their internal relations of production. In this context of changes, this paper analyzes the quality of employment in Brazilian agriculture in the years 1990-2010. Using data from the Relação Anual de Informações Sociais, from Ministry of Labor and Employment, the Formal Employment Quality Index was estimated in the agriculture sector in the period 1990-2010. Results demonstrate an advance in education, wage contraction and high standards of turnover, indicating replacement of labor in this segment.
Stacking disorder and thermal transport properties of $α$-RuCl$_3$
Creators: name: Zhang, Heda
name: McGuire, Michael A
name: May, Andrew F
name: Chao, Joy
name: Zheng, Qiang
name: Chi, Miaofang
name: Sales, Brian C
name: Mandrus, David G
name: Nagler, Stephen E
name: Miao, Hu
name: Ye, Feng
name: Yan, Jiaqiang
Publisher: name: arXiv
Year: 2023
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: $α$-RuCl$_3$, a well-known candidate material for Kitaev quantum spin liquid, is prone to stacking disorder due to the weak van der Waals bonding between the honeycomb layers. After a decade of intensive experimental and theoretical studies, the detailed correlation between stacking degree of freedom, structure transition, magnetic and thermal transport properties remains unresolved. In this work, we reveal the effects of a small amount of stacking disorder inherent even in high quality $α$-RuCl$_3$ crystals. This small amount of stacking disorder results in the variation of the magnetic ordering temperature, suppresses the structure transition and thermal conductivity. Crystals with minimal amount of stacking disorder have a T$_N>$7.4\,K and exhibit a well-defined structure transition around 140\,K upon cooling. For those with more stacking faults and a T$_N$ below 7\,K, the structure transition occurs well below 140\,K upon cooling and is incomplete, manifested by the diffuse streaks and the coexistence of both high temperature and low temperature phases down to the lowest measurement temperature. Both types of crystals exhibit oscillatory field dependent thermal conductivity and a plateau-like feature in thermal Hall resistivity in the field-induced quantum spin liquid state. However, $α$-RuCl$_3$ crystals with minimal amount of stacking disorder have a higher thermal conductivity that pushes the thermal Hall conductivity to be closer to the half-integer quantized value. These findings demonstrate a strong correlation between layer stacking, structure transition, magnetic and thermal transport properties, underscoring the importance of interlayer coupling in $α$-RuCl$_3$ despite the weak van der Waals bonding.
Thermodynamics of mixtures with strongly negative deviations from Raoult's law. XVII. Permittivities and refractive indices for alkan-1-ol + N,N-diethylethanamine systems at (293.15-303.15) K. Application of the Kirkwood-Fröhlich model
Creators: name: Hevia, Fernando
name: González, Juan Antonio
name: Cobos, Ana
name: de la Fuente, Isaías García
name: Sanz, Luis Felipe
Publisher: name: arXiv
Year: 2024
Subjects: subject: Chemical Physics (physics.chem-ph)
subject: FOS: Physical sciences

description: Relative permittivities at 1 MHz, $\varepsilon_{\text{r}}$, at 0.1 MPa and (293.15-303.15) K and refractive indices, $n_{\text{D}}$, at similar conditions have been measured for the alkan-1-ol (methanol, propan-1-ol, butan-1-ol, pentan-1-ol or heptan-1-ol) + N,N-diethylethanamine (TEA) systems. Positive values of the excess permittivities, $\varepsilon_{\text{r}}^{\text{E}}$ , are encountered for the methanol system at high alcohol concentrations. The remaining mixtures are characterized by negative $\varepsilon_{\text{r}}^{\text{E}}$ values over the whole composition range. At $ϕ_1$ (volume fraction) = 0.5, $\varepsilon_{\text{r}}^{\text{E}}$ changes in the order: methanol > propan-1-ol > butan-1-ol < pentan-1-ol < heptan-1-ol. Mixtures formed by alkan-1-ol and an isomeric amine, hexan-1-amine (HxA) or N-propylpropan-1-amine (DPA) or cyclohexylamine, behave similarly. This has been explained in terms of the lower and weaker self-association of longer alkan-1-ols. From the permittivity data, it is shown that: (i) (alkan-1-ol)-TEA interactions contribute positively to $\varepsilon_{\text{r}}^{\text{E}}$; (ii) TEA is an effective breaker of the network of the alkan-1-ols; (iii) structural effects, which are very important for the volumetric and calorimetric data of alkan-1-ol + TEA systems, are also relevant when evaluating dielectric data. This is confirmed by the comparison of $\varepsilon_{\text{r}}^{\text{E}}$ measurements for alkan-1-ol + aliphatic amine mixtures; (iv) the aromaticity effect (i.e., the replacement of TEA by pyridine in systems with a given alkan-1-ol) leads to an increase of the mixture polarization. Calculations conducted in the framework of the Kirkwood-Fröhlich model are consistent with the previous statements.
description: arXiv admin note: text overlap with arXiv:2409.11801, arXiv:2409.17926
Bell's inequality tests: from photons to B-mesons
Creators: name: Bramon, A.
name: Escribano, R.
name: Garbarino, G.
Publisher: name: arXiv
Year: 2004
Subjects: subject: Quantum Physics (quant-ph)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: We analyse the recent claim that a violation of a Bell's inequality has been observed in the $B$--meson system [A. Go, {\em Journal of Modern Optics} {\bf 51} (2004) 991]. The results of this experiment are a convincing proof of quantum entanglement in $B$--meson pairs similar to that shown by polarization entangled photon pairs. However, we conclude that the tested inequality is not a genuine Bell's inequality and thus cannot discriminate between quantum mechanics and local realistic approaches.
description: 5 pages
Calcium phosphate coatings on coronary stents by electrochemical deposition
Creators: name: Tsui, Manus Pui-Hung
Publisher: name: University of British Columbia
Year: 2010

description: Calcium phosphate ceramic coatings, especially hydroxyapatite (HA), have attracted much attention in the orthopedics and dentistry due to their excellent biocompatibility and bioactivity. Among the different methods of calcium phosphate coatings processing, electrochemical deposition (ECD) is a relatively low cost and flexible process technology. In this study, electrochemical deposition was used to deposit uniform calcium phosphate coatings on 316L stainless steel coronary stents. The influence of the ECD process parameters (deposition time, current density, electrolyte temperature, pH, and Ca/P ratio) on the resulting deposition morphology was investigated. Scanning electron microscopy (SEM) and X-Ray diffractometry (XRD) were used to analyze the coatings. The results demonstrated that both dicalcium phosphate dihydrate (CaHP0₄·2H₂0, DCPD) and hydroxyapatite (Ca₁₀(P0₄)(OH)₂, HA) were present in the uniform [tilde]0.5 [micro sign]m thick as-deposited coating. However, a post-treatment process, including a O.1N NaOH(aq) phase conversion at 75°C and a 500°C heat treatment produced a pure phase HA coating. The final deposit revealed a highly porous surface morphology which could be useful for drug encapsulation. With the application of the substrate surface modification and the post-treatment processes, sufficient coating adhesion was achieved as demonstrated by the in-vitro stent deployment tests without visible damage to the coating. Commercial in-vitro 40 million cycles fatigue tests demonstrated that the coatings exhibit good adhesion to the stent substrate, with no coating cracking or delamination. It was confirmed that the ECD-HA coating process for coronary stents is reliable and reproducible.
Zmiany w produkcji cukru w Polsce na tle Unii Europejskiej w pierwszej dekadzie XXI wieku
Creators: name: Artyszak, Arkadiusz
name: Artyszak, Arkadiusz
Publisher: name: Unknown
Year: 2013
Subjects: subject: Agribusiness
subject: Agricultural and Food Policy
subject: Community/Rural/Urban Development
subject: Crop Production/Industries
subject: Industrial Organization
subject: International Relations/Trade
subject: sugar production
subject: European Union
subject: / produkcja cukru
subject: Unia Europejska

description: The article presents the most important changes that have occurred in the sugar sector in Poland from 2001/2002 until 2010/2011. During this period, sugar production fell by 4.9%, the number of factories from 76 to 18, the daily processing by 57.2% and the number of employees during the campaign by 79.2%. At the same time the length of campaign has increased by 106.1%. / W artykule przedstawiono najważniejsze zmiany, jakie zaszły w sektorze cukrowniczym w Polsce od 2001/2002 roku do 2010/2011 roku. W tym okresie produkcja cukru zmniejszyła się o 4,9%, liczba zakładów z 76 do 18, dobowy przerób o 57,2%, a liczba zatrudnionych podczas kampanii o 79,2%. Jednocześnie długość kampanii wydłużyła się o 106,1%.
Density, speed of sound, refractive index and relative permittivity of methanol, propan-1-ol or pentan-1-ol + benzylamine liquid mixtures. Application of the Kirkwood-Fröhlich model
Creators: name: Hevia, Fernando
name: Alonso, Víctor
name: Cobos, Ana
name: González, Juan Antonio
name: Sanz, Luis Felipe
name: de la Fuente, Isaías García
Publisher: name: arXiv
Year: 2024
Subjects: subject: Chemical Physics (physics.chem-ph)
subject: FOS: Physical sciences

description: Densities ($ρ$), speeds of sound ($c$), relative permittivities at 1 MHz ($\varepsilon_{\text{r}}$) and refractive indices at the sodium D-line ($n_{\text{D}}$) at $T$ = (293.15 K to 303.15 K) and $p$ = 0.1 MPa are reported for binary liquid mixtures alkan-1-ol + benzylamine. Methanol, propan-1-ol and pentan-1-ol are the alkan-1-ols studied in this work. The values of the excess molar volume ($V_{\text{m}}^{\text{E}}$), excess isentropic compressibility ($κ_S^{\text{E}}$), excess speed of sound ($c^{\text{E}}$), excess refractive index ($n_{\text{D}}^{\text{E}}$), excess relative permittivity ($\varepsilon_{\text{r}}^{\text{E}}$) and its temperature derivative ${(\partial{\varepsilon_{\text{r}}}/\partial T)}_p$ are calculated, and they are adjusted to Redlich-Kister polynomials. The $V_{\text{m}}^{\text{E}}$ values are negative, indicating a predominance of the solvation between unlike molecules and structural effects. $\varepsilon_{\text{r}}^{\text{E}}$ values indicate a positive contribution from the creation of (alkan-1-ol)-benzylamine interactions, and the positive value for the methanol mixture emphasises the importance of solvation. Calculations on excess molar refractions point out to weaker dispersive interactions than in the ideal mixture, which may be explained by the mentioned solvation effects. The Kirkwood-Fröhlich model has been applied to the mixtures, and the Kirkwood correlation factors suggest an important relative weight, especially in the methanol system, of linear-like molecules in the solutions, which is in accordance with the positive contribution of the formed multimers to $\varepsilon_{\text{r}}^{\text{E}}$ due to their good effective response to the electric field.
description: arXiv admin note: substantial text overlap with arXiv:2409.17926
Convocatorias Planes y Programas educativos de Galicia para la CD 2019_2020
Creators: name: Alonso-Ferreiro, Almudena
Publisher: name: figshare
Year: 2020
Subjects: subject: 130306 Educational Technology and Computing
subject: FOS: Educational sciences
subject: Education
subject: 160506 Education Policy
subject: FOS: Political science

description: Enlaces a las Convocatorias de los planes y programas educativos de Galicia para la Competencia Digital.
Lemmas: Generation, Selection, Application
Creators: name: Rawson, Michael
name: Wernhard, Christoph
name: Zombori, Zsolt
name: Bibel, Wolfgang
Publisher: name: arXiv
Year: 2023
Subjects: subject: Logic in Computer Science (cs.LO)
subject: Artificial Intelligence (cs.AI)
subject: FOS: Computer and information sciences

description: Noting that lemmas are a key feature of mathematics, we engage in an investigation of the role of lemmas in automated theorem proving. The paper describes experiments with a combined system involving learning technology that generates useful lemmas for automated theorem provers, demonstrating improvement for several representative systems and solving a hard problem not solved by any system for twenty years. By focusing on condensed detachment problems we simplify the setting considerably, allowing us to get at the essence of lemmas and their role in proof search.
description: Extended version of the TABLEAUX 2023 contribution
New dynamics of the classical and nonlocal Gross-Pitaevskii equation with a parabolic potential
Creators: name: Liu, Shi-min
name: Wu, Hua
name: Zhang, Da-jun
Publisher: name: arXiv
Year: 2020
Subjects: subject: Exactly Solvable and Integrable Systems (nlin.SI)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: Solutions of the classical and nonlocal Gross-Pitaevskii (GP) equation with a parabolic potential and a gain term are derived by using a second order nonisospectral Ablowitz-Kaup-Newell-Segur system and reduction technique of double Wronskians. Solutions of the classical GP equation show typical space-time localized characteristics. An interesting dynamics, solitons carrying an oscillating wave, are found with mathematical analysis and illustrations. Solutions of some nonlocal cases are also illustrated.
description: 21 pages, 7 figures
Dust attenuation and star formation in the nearby universe: the ultraviolet and far-infrared points of view
Creators: name: Buat, Veronique
name: Iglesias-Paramo, Jorge
Publisher: name: arXiv
Year: 2004
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We make use of the on-going All Imaging Survey of the UV GALEX satellite cross-correlated with the IRAS all sky survey to build samples of galaxies trully selected in far-infrared or in ultraviolet. We discuss the amount of dust attenuation and the star formation rates for these galaxies and compare the properties of the galaxies selected in FIR or in UV.
description: 4 pages, proceedings of the conference: "Starbursts 2004 - From 30 Doradus to Lyman break galaxies" held in Cambridge, 6-10 September 2004
EXPORTAÇÕES BRASILEIRAS DE RECURSOS NATURAIS NÃO RENOVÁVEIS: COMPETITIVIDADE E PADRÕES DE ESPECIALIZAÇÃO
Creators: name: Maxir, Henrique Dos Santos
name: Faria, Rosane Nunes De
name: Maxir, Henrique Dos Santos
name: Faria, Rosane Nunes De
Publisher: name: Unknown
Year: 2013
Subjects: subject: International Relations/Trade
subject: Resource /Energy Economics and Policy
subject: non-renewable natural resources
subject: exports
subject: competitiveness
subject: comparative advantage

description: The purpose of this research is to analyze the dynamics of Brazilian exports of Non-Renewable Natural Resources (NRNR) over the period 2000-2012. The Revealed Comparative Advantage Index (RCA) and the Constant Market Share model (CMS) were calculated and the results showed that Brazil presented Revealed Comparative Advantage in exhaustible natural resource exports over the period, but these advantages were concentrated in ores, slag and ash; and iron and steel. It was found continuous increase in the VCR index for mineral fuels, distillation products etc., suggesting a shift in trend of comparative disadvantages for revealed comparative advantage in the next years. On the other hand, Brazil has reduced comparative advantages in exports of aluminum and articles thereof, presenting comparative disadvantages between 2010 and 2012.The commodity effect was the main factor contributing to the growth of Brazilian RNNR exports between 2004 and 2012, and the competitiveness effect was the main factor driving the growth of Brazilian NRNR exports from 2000 to 2003, characterized by the currency devaluation in Brazil.
Scope and Arbitration in Machine Learning Clinical EEG Classification
Creators: name: Zhu, Yixuan
name: Canham, Luke J. W.
name: Western, David
Publisher: name: arXiv
Year: 2023
Subjects: subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: A key task in clinical EEG interpretation is to classify a recording or session as normal or abnormal. In machine learning approaches to this task, recordings are typically divided into shorter windows for practical reasons, and these windows inherit the label of their parent recording. We hypothesised that window labels derived in this manner can be misleading for example, windows without evident abnormalities can be labelled `abnormal' disrupting the learning process and degrading performance. We explored two separable approaches to mitigate this problem: increasing the window length and introducing a second-stage model to arbitrate between the window-specific predictions within a recording. Evaluating these methods on the Temple University Hospital Abnormal EEG Corpus, we significantly improved state-of-the-art average accuracy from 89.8 percent to 93.3 percent. This result defies previous estimates of the upper limit for performance on this dataset and represents a major step towards clinical translation of machine learning approaches to this problem.
description: 10 pages, 6 figures
Physical Gluons and High $E_T$ Jets
Creators: name: Martin, A. D.
name: Roberts, R. G.
name: Stirling, W. J.
name: Thorne, R. S.
Publisher: name: arXiv
Year: 2004
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We propose a more physical parameterization of the gluon distribution for global parton analyses of deep inelastic and related hard scattering data. In the new parameterization the gluon distribution at large x in the MSbar-scheme is driven by the valence quarks, which naturally produces a shoulder-like form at high x, and hence produces a better description of the Tevatron inclusive jet data. We perform the new analysis at both NLO and NNLO. The improvement is found to be even better at NNLO than at NLO. We make available the new sets of NLO and NNLO partons, which we denote by MRST2004.
description: 11 pages, 5 figures. FORTRAN code for parton sets can be found at http://durpdg.dur.ac.uk/hepdata/mrs.html
Incidence of community-onset extended-spectrum β-lactamase-producing Escherichia coli and Klebsiella pneumoniae infections: an 11-year population-based study in Denmark
Creators: name: Richelsen, Rasmus
name: Smit, Jesper
name: Pavithra Laxsen Anru
name: Schønheyder, Henrik Carl
name: Nielsen, Henrik
Publisher: name: Taylor & Francis
Year: 2020
Subjects: subject: Medicine
subject: Microbiology
subject: FOS: Biological sciences
subject: Biotechnology
subject: 59999 Environmental Sciences not elsewhere classified
subject: FOS: Earth and related environmental sciences
subject: Ecology
subject: Immunology
subject: FOS: Clinical medicine
subject: Science Policy
subject: 110309 Infectious Diseases
subject: FOS: Health sciences
subject: Computational Biology

description: Background: Data elucidating trends of community-onset extended-spectrum β-lactamase (ESBL)-producing Escherichia coli and Klebsiella pneumoniae infections remain sparse in low prevalence areas. We conducted a population-based study to determine the incidence, temporal trends and co-resistance of community-onset ESBL infections. Methods: We identified all recorded episodes of E. coli and K. pneumoniae bacteraemia and urinary tract infections in adult patients (>15 years) in the North Denmark Region between 2007–2017. Using population-based registries, we obtained information on demographics and place of acquisition, and investigated the standardized incidence rates and temporal trends of community-onset ESBL infections and the associated patterns of co-resistance. Results: A total of 3741 episodes of community-onset ESBL E. coli or K. pneumoniae infections were observed during the study period, with the annual standardized incidence rate increasing from 7.5 to 105 per 100,000 person-years between 2007–2017. The increase was conveyed primarily by a rise in E. coli urinary tract infections shifting from being mainly healthcare-associated to community-acquired. ESBL-producing isolates increased from 0.5 to 4.0% with considerable co-resistance. Conclusion: The proportion of E. coli and K. pneumoniae isolates producing ESBL have increased considerably in the North Denmark Region. The increasing incidence and frequent co-resistance should raise awareness among physicians responsible for empirical antibiotic treatment.
AI versus AI in Financial Crimes and Detection: GenAI Crime Waves to Co-Evolutionary AI
Creators: name: Kurshan, Eren
name: Mehta, Dhagash
name: Bruss, Bayan
name: Balch, Tucker
Publisher: name: arXiv
Year: 2024
Subjects: subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: Adoption of AI by criminal entities across traditional and emerging financial crime paradigms has been a disturbing recent trend. Particularly concerning is the proliferation of generative AI, which has empowered criminal activities ranging from sophisticated phishing schemes to the creation of hard-to-detect deep fakes, and to advanced spoofing attacks to biometric authentication systems. The exploitation of AI by criminal purposes continues to escalate, presenting an unprecedented challenge. AI adoption causes an increasingly complex landscape of fraud typologies intertwined with cybersecurity vulnerabilities.
 Overall, GenAI has a transformative effect on financial crimes and fraud. According to some estimates, GenAI will quadruple the fraud losses by 2027 with a staggering annual growth rate of over 30% [27]. As crime patterns become more intricate, personalized, and elusive, deploying effective defensive AI strategies becomes indispensable. However, several challenges hinder the necessary progress of AI-based fincrime detection systems. This paper examines the latest trends in AI/ML-driven financial crimes and detection systems. It underscores the urgent need for developing agile AI defenses that can effectively counteract the rapidly emerging threats. It also aims to highlight the need for cooperation across the financial services industry to tackle the GenAI induced crime waves.
EFICIÊNCIA TÉCNICA DA EXTRAÇÃO DO PEQUI NO CEARÁ
Creators: name: Nunes, Erivelton De Souza
name: Sousa, Eliane Pinheiro De
name: Damasceno, Nagilane Parente
name: Nunes, Erivelton De Souza
name: Sousa, Eliane Pinheiro De
name: Damasceno, Nagilane Parente
Publisher: name: Unknown
Year: 2013
Subjects: subject: Production Economics
subject: Productivity Analysis
subject: efficiency
subject: pequi
subject: Ceará

description: Pequi is a native fruit that has relevant nutritional potential and plays an important role in the generation of employment and income in the places where it occurs. Therefore, this study aims to measure the technical efficiency scores of pequi extractivists of the state of Ceará. In order to achieve the proposed goal, the data envelopment analysis model (DEA) has been employed. The data are of primary nature, collected in 2013, directly with a sample of 86 pequi extractivists located in the municipality of Crato, in the state of Ceará. The results indicated that the pequi extractivists of the state of Ceará can reduce, on average, the costs with raw materials in 72% and 21%, respectively, in the models with constant and variable returns to scale, without compromising the production. In addition, it has been observed that, about the assumption of the model with constant returns to scale, the majority of the extractivists showed efficiency scores below 0.5, however, when one includes a convexity restriction, the majority of the extractivists obtain optimal efficiency level.
Influence of the spin quantum number $s$ on the zero-temperature phase transition in the square lattice $J$-$J'$ model
Creators: name: Darradi, R.
name: Richter, J.
name: Farnell, D. J. J.
Publisher: name: arXiv
Year: 2004
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We investigate the phase diagram of the Heisenberg antiferromagnet on the square lattice with two different nearest-neighbor bonds $J$ and $J'$ ($J$-$J'$ model) at zero temperature. The model exhibits a quantum phase transition at a critical value $J'_c > J$ between a semi-classically ordered Néel and a magnetically disordered quantum paramagnetic phase of valence-bond type, which is driven by local singlet formation on $J'$ bonds. We study the influence of spin quantum number $s$ on this phase transition by means of a variational mean-field approach, the coupled cluster method, and the Lanczos exact-diagonalization technique. We present evidence that the critical value $J'_c$ increases with growing $s$ according to $J'_c \propto s(s+1)$.
description: 13 pages, 6 figures
PREÇO INTERNACIONAL, TAXA DE CÂMBIO E O PREÇO PAGO AOS PRODUTORES BRASILEIROS DE SOJA
Creators: name: Sousa, Lucas Oliveira De
name: Ferreira, Marcelo Dias Paes
name: Sousa, Lucas Oliveira De
name: Ferreira, Marcelo Dias Paes
Publisher: name: Unknown
Year: 2013
Subjects: subject: Demand and Price Analysis
subject: Brazil
subject: exchange rate
subject: international price
subject: states

description: This paper aimed to verify how the international soybean price and the exchange rate influenced the formation of domestic soybean prices in the four largest producers of this commodity in Brazil – Mato Grosso, Paraná, Rio Grande do Sul and Goiás, from 1996 to 2011. For this, the vector error correction (VEC) model and the Test of Granger Causality were used. The results indicated that variations in international soybean price and in the exchange rate affect soybean prices in the four states, and Mato Grosso was the only state whose price was not influenced by the other states prices. In the long run, changes in the international soybean market and the foreign exchange market are fully transmitted to domestic prices and these prices are more influenced by the international price. In the short run, the markets followed the price relation of Mato Grosso with the international price and exchange rate. We conclude that the concern of producers about changes in the exchange rate is relevant, but the international price is the main element of the formation of domestic prices, the markets analyzed are integrated and Mato Grosso has relevance in pricing in key markets of this commodity.
title: Structurally constrained inversion by means of a Minimum Gradient Support regularizer
title: examples of FD-EMI data inversion constrained by GPR reflection data
titleType: Subtitle
Creators: name: Klose, Tim
name: Guillemoteau, Julien
name: Vignoli, Giulio
name: Walter, Judith
name: Herrmann, Andreas
name: Tronicke, Jens
Publisher: name: Universität Potsdam
Year: 2025
Subjects: subject: 550 Geowissenschaften

description: Many geophysical inverse problems are known to be ill-posed and, thus, requiring some kind of regularization in order to provide a unique and stable solution. 
A possible approach to overcome the inversion ill-posedness consists in constraining the position of the model interfaces. For a grid-based parameterization, such a structurally constrained inversion can be implemented by adopting the usual smooth regularization scheme in which the local weight of the regularization is reduced where an interface is expected. 
By doing so, sharp contrasts are promoted at interface locations while standard smoothness constraints keep affecting the other regions of the model. In this work, we present a structurally constrained approach and test it on the inversion of frequency-domain electromagnetic induction (FD-EMI) data using a regularization approach based on the Minimum Gradient Support stabilizer, which is capable to promote sharp transitions everywhere in the model, i.e., also in areas where no structural a prioriinformation is available. Using 1D and 2D synthetic data examples, we compare the proposed approach to a structurally constrained smooth inversion as well as to more standard (i.e., not structurally constrained) smooth and sharp inversions. 
Our results demonstrate that the proposed approach helps in finding a better and more reliable reconstruction of the subsurface electrical conductivity distribution, including its structural characteristics. Furthermore, we demonstrate that it allows to promote sharp parameter variations in areas where no structural information are available. Lastly, we apply our structurally constrained scheme to FD-EMI field data collected at a field site in Eastern Germany to image the thickness of peat deposits along two selected profiles. In this field example, we use collocated constant offset ground-penetrating radar (GPR) data to derive structural a priori information to constrain the inversion of the FD-EMI data. 
The results of this case study demonstrate the effectiveness and flexibility of the proposed approach.
description: Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe; 1469
CAPACIDADE DE PAGAMENTO PELA ÁGUA BRUTA UTILIZADA NA IRRIGAÇÃO PÚBLICA NA BACIA DO JAGUARIBE - CEARÁ
Creators: name: Campos, Roberio Telmo
name: Campos, Kilmer Coelho
name: Campos, Roberio Telmo
name: Campos, Kilmer Coelho
Publisher: name: Unknown
Year: 2013
Subjects: subject: Community/Rural/Urban Development
subject: Resource /Energy Economics and Policy
subject: Capacity of payment
subject: irrigation stakeholders
subject: bulk water

description: This paper aims to evaluate the producers’ capacity of payment for bulk water in the public irrigation districts at Jaguaribe basin as well as for group of producers in each irrigation district, which carries out agriculture and cattle raising as main farm activities. This study also aims to give support to the State actions concerning building a matrix of bulk water tariff for this basin. The study area is the Jaguaribe basin in the State of Ceará. The data were of primary source, which were gathered by the application of 76 questionnaires. The method used to calculate the capacity of payment is based on the residual approach. The results showed that the producers’ total capacity of payment was R$ 46.57 by 1,000 m3. The Icó-Lima Campos irrigation district showed the lowest capacity of payment for bulk water, among the districts investigated. The Jaguaribe-Apodi irrigation district (DIJA) had the largest capacity of payment among all, in which fruit is the main product. The subset of fruit producers showed higher capacity of payment (R$ 103.67/1000m3), overcoming, in almost three times, the subset of grain and cattle producers (R$ 34.50/1000m3) as well as the grain producers alone (R$ 37.47/1000m3). Some producers showed net return covering the current tariff charged by COGERH, while others did not have enough capacity of payment for bulk water.
title: Standard and auxiliary-based algebraic multigrid methods for elliptic PDEs
Creators: name: Roppert, Klaus
Publisher: name: TU Wien
Year: 2017
Subjects: subject: Mulitgrid
subject: Finite Elemente
subject: elliptische PDE
subject: Lineare Löser
subject: Multigrid
subject: Finite Elements
subject: elliptic PDE
subject: linear solver

description: In der folgenden Arbeit werden verschiedene Algebraische Multigrid Methoden (AMG) zur Lösung von elliptischen partiellen Differentialgleichungen zweiter Ordnung untersucht. Zu Beginn wird eine kurze, allgemeine Einführung in Multigrid Methoden gegeben, welche dann zu einem algebraischen Ansatz erweitert werden. Es wird eine Matlab-Umgebung zur Lösung dreier verschiedener physikalischer Felder entwickelt, um anschließend die vielversprechendsten Ansätze im institutseigenen Finite-Elemente Code CFS++ zu implementieren und mit anderen iterativen Gleichungslösern, anhand verschiedener Gleichungen mit unterschiedlichen Kern des linearen Operators, zu vergleichen. Mit den implementierten Lösern können elektrostatische, mechanische und elektromagnetische Probleme gelöst werden. Der Funktionenraum für die ersten beiden Felder umfasst lineare Lagrange-Ansatzfunktionen, wohingegen das letztere mit Kantenelementen diskretisiert wird.
description: In the following thesis, different algebraic multigrid methods (AMG) for the solution of elliptic second order PDEs are investigated. A short introduction into multigrid methods in general is given and extended to the algebraic approach. A matlab-framework is implemented to test different algorithms and applied to various physical fields, using AMG as a standalone-solver. The most promising methods were implemented in the in-house finite element code CFS++, tested and compared to other types of iterative solvers, for three types of equations with different kernels of the underlying linear operator. The associated physical fields for the three types of equations are electrostatic, 3D-mechanic and electromagnetic. The latter one, discretized using edge-elements, the first two using nodal Lagrangian ansatz-functions.
ANÁLISE DO COMPORTAMENTO DOS PREÇOS DO BOI GORDO E DO BOI MAGRO ENTRE 2000 e 2012
Creators: name: Boechat, Andréia Moreira Da Fonseca
name: Boechat, Andréia Moreira Da Fonseca
Publisher: name: Unknown
Year: 2013
Subjects: subject: Agribusiness
subject: Demand and Price Analysis
subject: Price
subject: VAR model
subject: Cattle
subject: Transmission prices

description: This article aims to analyze the effects of the shock on prices of cattle on the behavior of prices of feeder cattle in the period October 2000 to October 2012. The methodology used was the analysis of Unit Root Tests of Dickey-Fuller (ADF), Granger Causality, Johansen Co-Integration, Method Auto-Regressive (VAR), error variance decomposition and impulse response function. The results showed that there is a relationship between the prices of the two selected markets, confirming the hypothesis that the price of cattle influences the formation of the price of feeder cattle in the short term.
Shape index, Brouwer degree and Poincaré-Hopf theorem
Creators: name: Barge, Héctor
name: Sanjurjo, José M. R.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Dynamical Systems (math.DS)
subject: FOS: Mathematics

description: In this paper we study the relationship of the Brouwer degree of a vector field with the dynamics of the induced flow. Analogous relations are studied for the index of a vector field. We obtain new forms of the Poincar% é-Hopf theorem and of the Borsuk and Hirsch antipodal theorems. As an application, we calculate the Brouwer degree of the vector field of the Lorenz equations in isolating blocks of the Lorenz strange set.
Specjalizacja pozarolnicza podregionów przeważająco wiejskich w Polsce
Creators: name: Adamczyk, Piotr
name: Adamczyk, Piotr
Publisher: name: Unknown
Year: 2014
Subjects: subject: Agribusiness
subject: specialization
subject: Krugman Specialization Index
subject: predominantly rural subregion

description: The paper examines the non-agricultural specialization of predominantly rural subregions in Poland. The above mentioned specialization was measured by the Krugman Index. It was stated that sector structure of employed persons, gross value added and business entities resembles the country’s structure. It indicates low specialization of the predominantly rural subregions in non-agricultural activity. The specialization is mostly diverse in relation to gross value added. The industry is a dominant area of non-agricultural specialization.
High-energy neutrino emission subsequent to gravitational wave radiation from supermassive black hole mergers
Creators: name: Yuan, Chengchao
name: Murase, Kohta
name: Kimura, Shigeo S.
name: Mészáros, Péter
Publisher: name: arXiv
Year: 2020
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: Supermassive black hole (SMBH) coalescences are ubiquitous in the history of the Universe and often exhibit strong accretion activities and powerful jets. These SMBH mergers are also promising candidates for future gravitational wave detectors such as Laser Space Inteferometric Antenna (LISA). In this work, we consider neutrino counterpart emission originating from the jet-induced shocks. The physical picture is that relativistic jets launched after the merger will push forward inside the premerger disk wind material, and then they subsequently get collimated, leading to the formation of internal shocks, collimation shocks, forward shocks and reverse shocks. Cosmic rays can be accelerated in these sites and neutrinos are expected via the photomeson production process. We formulate the jet structures and relevant interactions therein, and then evaluate neutrino emission from each shock site. We find that month-to-year high-energy neutrino emission from the postmerger jet after the gravitational wave event is detectable by IceCube-Gen2 within approximately five to ten years of operation in optimistic cases where the cosmic-ray loading is sufficiently high and a mildly super-Eddington accretion is achieved. We also estimate the contribution of SMBH mergers to the diffuse neutrino intensity, and find that a significant fraction of the observed very high-energy ($E_ν\gtrsim1$ PeV) IceCube neutrinos could originate from them in the optimistic cases. In the future, such neutrino counterparts together with gravitational wave observations can be used in a multimessenger approach to elucidate in greater detail the evolution and the physical mechanism of SMBH mergers.
description: 17 pages, 9 figures, 1 table. Accepted for publication in PRD
Corrosion properties of nanocrystalline Co and Co-P alloys
Creators: name: Jung, Hundal
Publisher: name: University of British Columbia
Year: 2010

description: In this thesis, the corrosion properties of electrodeposited nanocrystalline Co and Co- 1.1 and 2.1 wt% P alloys (7 to 20 nm grain size) were investigated in a wide range of solution pH by using polarization and electrochemical impedance spectroscopy techniques along with scanning electron microscopy, energy dispersive X-ray spectroscopy, transmission electron microscopy and X-ray photoelectron spectroscopy analysis. In 0.1 M H₂SO₄ and 0.5 M Na₂SO₄ solutions (pH 1 and 3, rspectively), nanocrystalline Co showed higher anodic and cathodic reaction rates and reduced localized corrosion attack compared to coarse grained Co counterparts. An enhanced electrochemical reaction rate of nanocrystalline Co was correlated to a significant increase in grain boundaries and triple junctions. For pure Co, a catalytic mechanism has been suggested to rationalize a more favorable route for their anodic dissolution reaction. An addition of P leads to a significant increase of corrosion resistance of nanocrystalline Co-P due to the increased elemental P concentration On the corroded surface at E [sub oc] following an initial selective dissolution of Co. However, at higher anodic overpotential, the superior corrosion resistance of nanocrystalline Co-P did not last due to the formation of a porous and defective surface film. The excellent corrosion resistance of nanocrystalline Co-P deteriorated from heat treatment at 350 °C and 800 °C due to higher chemical heterogeneity. In a 3.56 % NaCl solution at pH 6.2, nanocrystalline Co-P showed a higher anodic dissolution rate than that of nanocrystalline Co due to a reduced adsorption area of chloride ions. However, the corrosion rate of nanocrystalline Co-P decreased in comparison to nanocrystalline Co due to a much smaller cathodic exchange current density for oxygen reduction on nanocrystalline Co-P. A physical model was elaborated to explain the different response of annealed nanocrystalline Co-P by considering the different adsorption properties of chloride ions. In a 0.1 M NaOH solution at pH 13, all tested Co and Co-P samples exhibited active-passive-transpassive behaviors with the onset of primary and secondary passivations. While anodic polarization curves for poly- and nanocrystalline Co had qualitatively very similar behavior, nanocrystalline Co-P showed higher passivation current densities due to their decreased passive film resistance and reduced film thickness. XPS analysis revealed that the passive film formed in the primary passivation ranges was consisted of mainly Co(OH)₂ with a thickness of >10 nm. The passive film formed during secondary passivation consisted of rather complex compounds such as CO₃O₄, CO₂O₃, Co(OH)₃ as well as Co(OH)₂ with a thickness of <10 nm. This last finding was common to poly- and nanocrystalline Co and nanocrystalline Co-1.1 wt% P.
Comment on ``Dynamical role of anyonic excitation statistics in rapidly rotating Bose gases"
Creators: name: Ghosh, Pijush K.
Publisher: name: arXiv
Year: 2004
Subjects: subject: Other Condensed Matter (cond-mat.other)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We comment on the work of Fischer, Phys. Rev. Lett. 93, 160403 (2004). Contrary to the claim in the letter, we argue that the anyonic excitation statistics does not play any dynamical role in stabilizing attractive bose gases under rapid rotation in a fractional quantum Hall state. We also point out that the assertion of obtaining exact solutions of the self-dual equation that saturates the Bogomol'nyi bound is invalid for non-zero external field.
description: 2 pages, no figure(v1); Version to appear in Physical Review Letters, re-written the last sentence of the third paragraph(v2)
Sytuacja ekonomiczna rolniczych spółdzielni produkcyjnych w latach 2010-2012
Creators: name: Adamski, Marcin
name: Adamski, Marcin
Publisher: name: Unknown
Year: 2014
Subjects: subject: Agribusiness
subject: agricultural production cooperatives
subject: cooperatives farms
subject: financial results

description: The aim of this study was to show the changes that occurred in the group of large-scale farms functioning in a form of agricultural production cooperatives (APC) in the years 2010-2012. Due to little availability of information concerning this form of farms in Poland, the data for the analysis were gathered from the database of the Institute of Agricultural and Food Economics National Research Institute. This database was created in connection with the annual publication of Top 100 APC. The analyses show that the surveyed group of cooperatives in the years 2010-2012 improved its financial results and conducted intensive investment processes.
Enhanced cavity coupling to silicon monovacancies in 4-H Silicon Carbide using below bandgap laser irradiation and low temperature thermal annealing
Creators: name: Gadalla, Mena N.
name: Greenspon, Andrew S.
name: Defo, Rodrick Kuate
name: Zhang, Xingyu
name: Hu, Evelyn L.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Optics (physics.optics)
subject: Applied Physics (physics.app-ph)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: The negatively charged silicon monovacancy $V_{Si}^-$ in 4H-silicon carbide (SiC) is a spin-active point defect that has the potential to act as a qubit or quantum memory in solid-state quantum computation applications. Photonic crystal cavities (PCCs) can augment the optical emission of the $V_{Si}^-$, yet fine-tuning the defect-cavity interaction remains challenging. We report on two post-fabrication processes that result in enhancement of the $V_1^{'}$ optical emission from our 1-dimensional PCCs, indicating improved coupling between the ensemble of silicon vacancies and the PCC. One process involves below bandgap illumination at 785 nm and 532 nm wavelengths and above bandgap illumination at 325 nm, carried out at times ranging from a few minutes to several hours. The other process is thermal annealing at $100^o C$, carried out over 20 minutes. Every process except above bandgap irradiation improves the defect-cavity coupling, manifested in augmented Purcell factor enhancement of the $V_1^{'}$ zero phonon line at 77K. The below bandgap laser process is attributed to a modification of charge states, changing the relative ratio of $V_{Si}^0$ (dark state) to $V_{Si}^-$ (bright state), while the thermal annealing process may be explained by diffusion of carbon interstitials, $C_i$, that subsequently recombine with other defects to create additional $V_{Si}^-$s. Above bandgap radiation is proposed to initially convert $V_{Si}^{0}$ to $V_{Si}^-$, but also may lead to diffusion of $V_{Si}^-$ away from the probe area, resulting in an irreversible reduction of the optical signal. Observations of the PCC spectra allow insights into defect modifications and interactions within a controlled, designated volume and indicate pathways to improve defect-cavity interactions.
description: 21 pages, 8 figures