cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
QuanEstimation: An open-source toolkit for quantum parameter estimation
Creators: name: Zhang, Mao
name: Yu, Huai-Ming
name: Yuan, Haidong
name: Wang, Xiaoguang
name: Demkowicz-Dobrzański, Rafał
name: Liu, Jing
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Physics (quant-ph)
subject: High Energy Physics - Theory (hep-th)
subject: Computational Physics (physics.comp-ph)
subject: FOS: Physical sciences

description: Quantum parameter estimation promises a high-precision measurement in theory, however, how to design the optimal scheme in a specific scenario, especially under a practical condition, is still a serious problem that needs to be solved case by case due to the existence of multiple mathematical bounds and optimization methods. Depending on the scenario considered, different bounds may be more or less suitable, both in terms of computational complexity and the tightness of the bound itself. At the same time, the metrological schemes provided by different optimization methods need to be tested against realization complexity, robustness, etc. Hence, a comprehensive toolkit containing various bounds and optimization methods is essential for the scheme design in quantum metrology. To fill this vacancy, here we present a Python-Julia-based open-source toolkit for quantum parameter estimation, which includes many well-used mathematical bounds and optimization methods. Utilizing this toolkit, all procedures in the scheme design, such as the optimizations of the probe state, control and measurement, can be readily and efficiently performed.
description: 40 pages, 20 figures. Close to the published version. Corresponding package version: v0.2.0 (Python) v0.1.3 (Julia)
Stability result for projective modules over blowup rings
Creators: name: Keshari, Manoj Kumar
Publisher: name: arXiv
Year: 2004
Subjects: subject: Commutative Algebra (math.AC)
subject: FOS: Mathematics
subject: 13C10

description: Let R be an affine algebra of dimension n \geq 3 over an algebraically closed field k. Suppose char k =0 or char k =p \geq n. Let g,f_1,...,f_r be a R-regular sequence and A=R[f_1/g,...,f_r/g]. Let P be a projective A-module of rank n-1 which is extended from R. Let (a,p) \in (A \op P) be a unimodular element and Q=A\op P/(a,p)A. Then, Q is extended from R. A similar result for affine algebras over reals are also proved.
description: 15 pages
Causalidade e transmissão entre os preços de mandioca, trigo, milho e seus derivados no Paraná
Creators: name: Alves, Lucilio Rogerio Aparecido
name: Cardoso, Carlos Estevao Leite
name: Felipe, Fabio Isaias
name: Campion, Michele Tubero
name: Alves, Lucilio Rogerio Aparecido
name: Cardoso, Carlos Estevao Leite
name: Felipe, Fabio Isaias
name: Campion, Michele Tubero
Publisher: name: Unknown
Year: 2006
Subjects: subject: Demand and Price Analysis
subject: Granger causality
subject: Price transmission
subject: Starch

description: This study aims to analyze the relations of causality and price transmission of the cassava root, the cassava starch, the cassava flour, the wheat, the wheat flour and the corn, in the State of Parana. The used data goes from January 1995 to December 2005, with monthly regularity. It was applied the methodology of Granger causality to test the relations between the variables. The results showed long term relations between corn and cassava root prices, cassava starch and cassava flour prices, wheat and corn prices and wheat and wheat flour prices. It was emphasized the dependence of the cassava root prices in relation to corn, wheat, cassava starch and cassava flour prices and its little influence on these variables. It was also noted that cassava flour prices influenced the cassava starch prices, and the strong relation between the wheat prices and the wheat flour prices. The cassava flour and the wheat prices presented lesser dependence of the others variables. The paper concluded that there are important interrelations between the studied variables. The cassava root prices were the ones that depended most on the other variables in this study.
Quantum correlations beyond entanglement in a classical-channel model of gravity
Creators: name: Roccati, Federico
name: Militello, Benedetto
name: Fiordilino, Emilio
name: Iaria, Rosario
name: Burderi, Luciano
name: Di Salvo, Tiziana
name: Ciccarello, Francesco
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Physics (quant-ph)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: A direct quantization of the Newtonian interaction between two masses is known to establish entanglement, which if detected would witness the quantum nature of the gravitational field. Gravitational interaction is yet compatible also with gravitational decoherence models relying on classical channels, hence unable to create entanglement. Here, we show in paradigmatic cases that, despite the absence of entanglement, a classical-channel model of gravity can still establish quantum correlations in the form of quantum discord between two masses. This is demonstrated for the Kafri-Taylor-Milburn (KTM) model and a recently proposed dissipative extension of this. In both cases, starting from an uncorrelated state, a significant amount of discord is generally created. This eventually decays in the KTM model, while it converges to a small stationary value in its dissipative extension. We also find that initial local squeezing on the state of the masses can significanlty enhance the generated discord.
description: 8 pages, 5 figures
Spin-glass thermo-remanent magnetization revisited: a numerical and analytical study
Creators: name: Sibani, Paolo
name: Kirketerp, Jacob Møller
Publisher: name: arXiv
Year: 2020
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: FOS: Physical sciences

description: Thermoremanent magnetization data for the 3D Edwards-Anderson spin glass are generated using the Waiting Time Method as simulational tool and interpreted using Record Dynamics. We verify that clusters of contiguous spins are overturned by quakes, non-equilibrium events linked to record sized energy fluctuations and show that quaking is a log-Poisson process, i.e. a Poisson process whose average depends on the logarithm of the system age, counted from the initial quench. Our results compare favorably with experimental thermoremanent magnetization findings and with the spontaneous fluctuation dynamics of the E-A model. The logarithm growth of the size of overturned clusters is related to similar experimental results and to the growing length scale of the spin-spin spatial correlation function. The analysis buttresses the applicability of the Waiting Time Method as a simulational tool and of Record Dynamics as coarse-graining method for aging dynamics.
description: 7 pages, 5 figures
Fluctuation Properties and Polar Emission Mapping of Pulsar B0834+06 at Decameter Wavelengths
Creators: name: Asgekar, Ashish
name: Deshpande, Avinash A.
Publisher: name: arXiv
Year: 2004
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Recent results regarding subpulse-drift in pulsar B0943+10 have led to the identification of a stable system of sub-beams circulating around the magnetic axis of the star. Here, we present single-pulse analysis of pulsar B0834+06 at 35 MHz, using observations from the Gauribidanur Radio Telescope. Certain signatures in the fluctuation spectra and correlations allow estimation of the circulation time and drift direction of the underlying emission pattern responsible for the observed modulation. We use the `cartographic transform' mapping technique to study the properties of the polar emission pattern. These properties are compared with those for the other known case of B0943+10, and the implications are discussed.
description: (v3: minor changes); 9 pages, 6 figures (11 ps files); To appear in MNRAS
Análise de risco para o café em Minas Gerais
Creators: name: Rugani, Felipe Do Lago
name: Silveira, Suely De Fatima Ramos
name: Rugani, Felipe Do Lago
name: Silveira, Suely De Fatima Ramos
Publisher: name: Unknown
Year: 2006
Subjects: subject: Risk and Uncertainty
subject: Risk Management
subject: VaR
subject: Coffee

description: The coffee is one of the most important products in the economy of Minas Gerais. In some specific places it has a great importance in the local production, but in any place the economic players involved in that market have the same trouble: the share of risk taken by them. Therefore, would be really important, and useful, to calculate the risk share of each player. Than, this article showed the risk amount absorbed by the players in the coffee market of Minas Gerais, based in the prices paid in the south of that state, the greatest region producer, trough two models of Value at Risk (VaR), the Normal Model and the Historic Simulation Model. The results shows a risk absorbed about 17,28%, with 95% of sure, and 24,60% with 99% of sure, both of them in a thirty days exposure, calculated by the Historic Simulation VaR Model, which was the most trustable, with less exceptions. Besides, the compare between the risks of coffee, Ibovespa and dollar, all of them calculated by VaR Historic Simulation, evidence the coffee as the most risk full of them, with the greatest amount of risk value.
Análise da estrutura do mercado brasileiro de carros populares, 1990-2005
Creators: name: Mattos, Leonardo Bornacki De
name: Barros, Áther De Miranda
name: Mattos, Leonardo Bornacki De
name: Barros, Áther De Miranda
Publisher: name: Unknown
Year: 2006
Subjects: subject: Industrial Organization
subject: Industrial organization
subject: Market structure Popular cars

description: The objective of this paper was to analyze the evolution of the Structure of the Brazilian market of popular cars in the period from 1990 to 2005. Information on the number of units sold by each firm in the domestic market have been used to determine each firm’s market-share, levels of concentration and the Herfindahl- Hirschman Index. The results have pointed that, although reduction in the concentration of this market during the period have occurred, the market is still strongly concentrated according to the levels established by the Office of Economic Investigation (SEAE) and by the Office of Economic Defense (SDE) for the exercise of the coordinated market power.
Portfolio selection models: comparative analysis and applications to the Brazilian stock market
Creators: name: Farias, Christiano Alves
name: Vieira, Wilson Da Cruz
name: Santos, Maurinho Luiz Dos
name: Farias, Christiano Alves
name: Vieira, Wilson Da Cruz
name: Santos, Maurinho Luiz Dos
Publisher: name: Unknown
Year: 2006
Subjects: subject: Financial Economics
subject: Portfolio selection
subject: Stock market
subject: Brazil

description: This paper presents a comparison of three portfolio selection models, Mean-Variance (MV), Mean Absolute Deviation (MAD), and Minimax, as applied to the Brazilian Stock Market (BOVESPA). For this comparison, we used BOVESPA data from three different 12 month time periods: 1999 to 2000, 2001, and 2002 to 2003. Each model generated three optimal portfolios for each period, with performance determined by monthly returns over the period. In general, the accumulated returns from the Minimax modeled portfolios were superior to the BOVESPA’s principal index, the IBOVESPA. The MV model was the least efficient for portfolio selection.
Crop switching as a strategy for adapting to climate change
Creators: name: Kurukulasuriya, Pradeep
name: Mendelsohn, Robert
name: Kurukulasuriya, Pradeep
name: Mendelsohn, Robert
Publisher: name: Unknown
Year: 2008
Subjects: subject: Crop Production/Industries
subject: Resource /Energy Economics and Policy
subject: Adaptation
subject: Climate change
subject: Crops
subject: Africa

description: This paper examines the impact of climate change on primary crops grown in Africa. An innovative approach is presented that bridges the gap between agro-economic and traditional Ricardian models. We label it a ‘structural Ricardian model’. It first captures the type of crop a farmer will select and then examines the conditional net revenue of that crop. The model is estimated using a sample of over 5000 farmers across 11 countries in Africa. The analysis finds that farmers shift the crops they plant to match the climate they face. Studies that fail to account for crop switching will overestimate the damages from climate change and underestimate the benefits.
Fe3O4(001) films on Fe(001) - termination and reconstruction of iron rich surfaces
Creators: name: Spiridis, N.
name: Barbasz, J.
name: Lodziana, Z.
name: Korecki, J.
Publisher: name: arXiv
Year: 2005
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: High-quality and impurity-free magnetite surfaces with (sqrt2xsqrt2)R45o reconstruction have been obtained for the Fe3O4(001) epitaxial films deposited on Fe(001). Based on atomically resolved STM images for both negative and positive sample polarity and Density Functional Theory calculations, a model of the magnetite (001) surface terminated with Fe ions forming dimers on the reconstructed (sqrt2xsqrt2)R45o octahedral iron layer is proposed.
description: 17 pages 4 figures
Regulatory SPS instruments in meat trade
Creators: name: Schlueter, Simon W.
name: Wieck, Christine
name: Heckelei, Thomas
name: Schlueter, Simon W.
name: Wieck, Christine
name: Heckelei, Thomas
Publisher: name: Unknown
Year: 2009
Subjects: subject: Agricultural and Food Policy
subject: Food Consumption/Nutrition/Food Safety
subject: International Relations/Trade
subject: agri-food trade
subject: gravity model
subject: Poisson regression

description: Policy makers have to choose between different potentially risk-reducing instruments regulating agri-food trade. Analysing the meat sector, the paper aims at identifying least trade distorting regulations for different policy goals relevant to the SPS agreement. For this purpose, a non-linear gravity model is estimated by Poisson pseudo-maximum likelihood and applied to a panel data set at HS 4-digit level. Regulations are distinguished by a frequency approach allowing to identify the least trade distorting regulation for each policy objective. The results suggest significant differences of trade impacts between types of sanitary regulations.
A BAYESIAN ALTERNATIVE TO GENERALIZED CROSS ENTROPY SOLUTIONS FOR UNDERDETERMINED ECONOMETRIC MODELS
Creators: name: Heckelei, Thomas
name: Mittelhammer, Ronald C.
name: Jansson, Torbjorn
name: Heckelei, Thomas
name: Mittelhammer, Ronald C.
name: Jansson, Torbjorn
Publisher: name: Unknown
Year: 2008
Subjects: subject: Research Methods/ Statistical Methods
subject: Underdetermined Equation Systems
subject: Maximum Entropy
subject: Bayesian Priors
subject: Structural Estimation
subject: Calibration

description: This paper presents a Bayesian alternative to Generalized Maximum Entropy (GME) and Generalized Cross Entropy (GCE) methods for deriving solutions to econometric models represented by underdetermined systems of equations. For certain types of econometric model specifications, the Bayesian approach provides fully equivalent results to GME-GCE techniques. However, in its general form, the proposed Bayesian methodology allows a more direct and straightforwardly interpretable formulation of available prior information and can reduce significantly the computational effort involved in finding solutions. The technique can be adapted to provide solutions in situations characterized by either informative or uninformative prior information.
M-atom conductance oscillations of a metallic quantum wire
Creators: name: Kwapinski, T.
Publisher: name: arXiv
Year: 2004
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: The electron transport through a monoatomic metallic wire connected to leads is investigated using the tight-binding Hamiltonian and Green's function technique. Analytical formulas for the transmittance are derived and M-atom oscillations of the conductance versus the length of the wire are found. Maxima of the transmittance function versus the energy, for the wire consisted of N atoms, determine the (N+1) period of the conductance. The periods of conductance oscillations are discussed and the local and average quantum wire charges are presented. The average charge of the wire is linked with the period of the conductance oscillations and it tends to the constant value as the length of the wire increases. For M-atom periodicity there are possible (M-1) average occupations of the wire states.
description: 8 pages, 5 figures. J.Phys.: Condens. matter (2005) accepted
Lifetime of the hypertriton
Creators: name: Hildenbrand, F.
name: Hammer, H. -W.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Nuclear Theory (nucl-th)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We calculate the lifetime of the hypertriton as function of the $Λ$ separation energy $B_Λ$ in an effective field theory with $Λ$ and deuteron degrees of freedom. We also consider the impact of new measurements of the weak decay parameter of the $Λ$. While the sensitivity of the total width to $B_Λ$ is small, the partial widths for decays into individual final states and the experimentally measured ratio $R=Γ_{^3\textrm{He}}/\left(Γ_{^3 \text{He}}+Γ_{pd}\right)$ show a strong dependence. For the standard value $B_Λ=(0.13\pm 0.05)$ MeV, we find $R=0.37\pm 0.05$, which is in good agreement with past experimental studies and theoretical calculations. For the recent STAR value $B_Λ=(0.41\pm0.12\pm0.11)$ MeV, we obtain $R=0.57\pm 0.11$.
description: 17 pages, 9 figures, J=3/2 FSI added, typos corrected
Heuristics for Link Prediction in Multiplex Networks
Creators: name: Tillman, Robert E.
name: Potluru, Vamsi K.
name: Chen, Jiahao
name: Reddy, Prashant
name: Veloso, Manuela
Publisher: name: arXiv
Year: 2020
Subjects: subject: Machine Learning (cs.LG)
subject: Social and Information Networks (cs.SI)
subject: Machine Learning (stat.ML)
subject: FOS: Computer and information sciences

description: Link prediction, or the inference of future or missing connections between entities, is a well-studied problem in network analysis. A multitude of heuristics exist for link prediction in ordinary networks with a single type of connection. However, link prediction in multiplex networks, or networks with multiple types of connections, is not a well understood problem. We propose a novel general framework and three families of heuristics for multiplex network link prediction that are simple, interpretable, and take advantage of the rich connection type correlation structure that exists in many real world networks. We further derive a theoretical threshold for determining when to use a different connection type based on the number of links that overlap with an Erdos-Renyi random graph. Through experiments with simulated and real world scientific collaboration, transportation and global trade networks, we demonstrate that the proposed heuristics show increased performance with the richness of connection type correlation structure and significantly outperform their baseline heuristics for ordinary networks with a single connection type.
Device-independent uncloneable encryption
Creators: name: Kundu, Srijita
name: Tan, Ernest Y. -Z.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Uncloneable encryption, first introduced by Broadbent and Lord (TQC 2020) is a quantum encryption scheme in which a quantum ciphertext cannot be distributed between two non-communicating parties such that, given access to the decryption key, both parties cannot learn the underlying plaintext. In this work, we introduce a variant of uncloneable encryption in which several possible decryption keys can decrypt a particular encryption, and the security requirement is that two parties who receive independently generated decryption keys cannot both learn the underlying ciphertext. We show that this variant of uncloneable encryption can be achieved device-independently, i.e., without trusting the quantum states and measurements used in the scheme, and that this variant works just as well as the original definition in constructing quantum money. Moreover, we show that a simple modification of our scheme yields a single-decryptor encryption scheme, which was a related notion introduced by Georgiou and Zhandry. In particular, the resulting single-decryptor encryption scheme achieves device-independent security with respect to a standard definition of security against random plaintexts. Finally, we derive an "extractor" result for a two-adversary scenario, which in particular yields a single-decryptor encryption scheme for single bit-messages that achieves perfect anti-piracy security without needing the quantum random oracle model.
description: Updated references for publication in Quantum. Note updated formulation of security definition, to avoid an underspecification issue in previous work (see Remark 4)
Emergence of Fermi's Golden Rule
Creators: name: Micklitz, Tobias
name: Morningstar, Alan
name: Altland, Alexander
name: Huse, David A.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Physics (quant-ph)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Fermi's Golden Rule (FGR) applies in the limit where an initial quantum state is weakly coupled to a {\it continuum} of other final states overlapping its energy. Here we investigate what happens away from this limit, where the set of final states is discrete, with a nonzero mean level spacing; this question arises in a number of recently investigated many-body systems. For different symmetry classes, we analytically and/or numerically calculate the universal crossovers in the average decay of the initial state as the level spacing is varied, with the Golden Rule emerging in the limit of a continuum. Among the corrections to the exponential decay of the initial state given by FGR is the appearance of the spectral form factor in the long-time regime for small but nonzero level spacing.
description: 4 pages, 2 figures, supplementary material
On fitting the Pareto-Levy distribution to stock market index data: selecting a suitable cutoff value
Creators: name: Coronel-Brizio, H. F.
name: Hernandez-Montoya, A. R.
Publisher: name: arXiv
Year: 2004
Subjects: subject: Other Condensed Matter (cond-mat.other)
subject: Statistical Finance (q-fin.ST)
subject: FOS: Physical sciences
subject: FOS: Economics and business

description: The so-called Pareto-Levy or power-law distribution has been successfully used as a model to describe probabilities associated to extreme variations of worldwide stock markets indexes data and it has the form $Pr(X>x) ~ x**(-alpha) for gamma< x
description: Econophysics paper. 5 pages 9 figures
Intrusion of buildings in natural environments : identifying the new environmental change regime
Creators: name: Undurraga, Jaime Esteban
Publisher: name: University of British Columbia
Year: 2009

description: This thesis examines the degenerative processes of planning procedures and buildings intruding in natural environments as the result of a dysfunctional social value of nature. Such intrusions are assumed to embody a notion of detachment of artificial processes from those of nature, leading to unexpected changes in the natural environment. Unlike urban environments, previously undeveloped locations present no artificial thresholds in the ecological relationship between buildings and nature. The likely isolation of these "social" artefacts intervening in previously undeveloped natural environments is examined in order to stress the functional interaction between natural and artificially contrasting systems as developing a new environmental change regime. Such direct connections highlight the need for accurate design considerations regarding the local conditions of ecological functioning, especially if such conditions are to be maintained. Therefore, a central question of this thesis is not whether buildings should or should not be placed in non-urban locations, but how. Revisiting core concepts from scientific fields, and especially, understanding how theories about the natural environment are constructed comprise a driving strategy in specifying the potential role of planning and design within these processes of land modification. A common ground of analysis and understanding for both scientific disciplines and design processes not (traditionally) involved in environmental evaluations is thus encouraged. The core intent of this thesis is to offer an integrated vision of an ongoing and yet dysfunctional relationship between buildings and natural environments. If the final artificial intervention's layout and its consequent environmental performance considers the landscape structure and functioning as an integral part of the building system, then the building becomes unique to that particular place. By embracing a profound understanding of this functional dependency on the larger natural system, a "sustainable synthesis of nature and culture" (Forman 2001) may hopefully be accomplished.
Apacic++ 2.0, A Parton Cascade In C++
Creators: name: Krauss, F.
name: Schaelicke, A.
name: Soff, G.
Publisher: name: arXiv
Year: 2005
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: The new version of the parton shower module APACIC++ for the SHERPA event generator framework is presented. It incorporates some features, that are specific for the consistent merging with multi-particle matrix elements at tree-level. This publication also includes some exemplary results and a short description of the upgraded class structure of APACIC++, version 2.0.
description: 42 pp
Deep-learning-based reconstruction of the neutrino direction and energy for in-ice radio detectors
Creators: name: Glaser, C.
name: McAleer, S.
name: Stjärnholm, S.
name: Baldi, P.
name: Barwick, S. W.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: Ultra-high-energy (UHE) neutrinos ($>10^{16}$ eV) can be measured cost-effectively using in-ice radio detection, which has been explored successfully in pilot arrays. A large radio detector is currently being constructed in Greenland with the potential to measure the first UHE neutrino, and an order-of-magnitude more sensitive detector is being planned with IceCube-Gen2. For such shallow radio detector stations, we present an end-to-end reconstruction of the neutrino energy and direction using deep neural networks (DNNs) developed and tested on simulated data. The DNN determines the energy with a standard deviation of a factor of two around the true energy ($σ\approx$ 0.3 in $\log_{10}(E)$), which meets the science requirements of UHE neutrino detectors. For the first time, we are able to predict the neutrino direction precisely for all event topologies including the complicated electron neutrino charged-current ($ν_e$-CC) interactions. The obtained angular resolution shows a narrow peak at $\mathcal{O}$($1^\circ)$ with extended tails that push the 68\% quantile for non-$ν_e$-CC (resp. $ν_e$-CC interactions) to $4^\circ (5^\circ)$. This highlights the advantages of DNNs for modeling the complex correlations in radio detector data, thereby enabling measurement of neutrino energy and direction.
description: Replaced with published version
The Production and Price Impact of Biotech Crops
Creators: name: Brookes, Graham
name: Yu, Tun-Hsiang (Edward)
name: Tokgoz, Simla
name: Elobeid, Amani E.
name: Brookes, Graham
name: Yu, Tun-Hsiang (Edward)
name: Tokgoz, Simla
name: Elobeid, Amani E.
Publisher: name: Unknown
Year: 2010
Subjects: subject: Crop Production/Industries
subject: Demand and Price Analysis
subject: Productivity Analysis
subject: biotechnology
subject: cereals
subject: crop yields
subject: oilseeds
subject: price effects
subject: productivity.

description: Biotech crops have now been grown commercially on a substantial global scale since 1996. This paper examines the production effects of the technology and impacts on cereal and oilseed markets through the use of agricultural commodity models. It analyses the impacts on global production, consumption, trade and prices in the soybean, canola and corn sectors. The analysis suggests that world prices of corn, soybeans and canola would probably be, respectively, 5.8%, 9.6% and 3.8% higher, on average, than 2007 baseline levels if this technology was no longer available to farmers. Prices of key derivatives of soybeans (meal and oil) would also be between 5% and 9% higher, with rapeseed meal and oil prices being about 4% higher than baseline levels. World prices of related cereals and oilseeds would also be expected to be higher by 3% to 4%. The effect of no longer using the current widely used biotech traits in the corn, soybean and canola sectors would probably impact negatively on both the global supply and utilization of these crops, their derivatives and related markets for grain and oilseeds. The modelling suggests that average global yields would fall for corn, soybeans and canola and despite some likely “compensating” additional plantings of these three crops, there would be a net fall in global production of the three crops of 14 million tonnes. Global trade and consumption of these crops/derivatives would also be expected to fall. The production and consumption of other grains such as wheat, barley and sorghum and oilseeds, notably sunflower, would also be affected. Overall, net production of grains and oilseeds (and derivatives) would fall by 17.7 million tonnes and global consumption would fall by 15.4 million tonnes. The cost of consumption would also increase by $20 billion (3.6%) relative to the total cost of consumption of the (higher) biotech-inclusive level of world consumption. The impacts identified in this analysis are, however, probably conservative, reflecting the limitations of the methodology used. In particular, the limited research conducted to date into the impact of the cost-reducing effect of biotechnology (notably in herbicide-tolerant soybeans) on prices suggests that the price effects identified in this paper represent only part of the total price impact of the technology.
An Effective and Efficient Evolutionary Algorithm for Many-Objective Optimization
Creators: name: Xue, Yani
name: Li, Miqing
name: Liu, Xiaohui
Publisher: name: arXiv
Year: 2022
Subjects: subject: Neural and Evolutionary Computing (cs.NE)
subject: FOS: Computer and information sciences

description: In evolutionary multiobjective optimization, effectiveness refers to how an evolutionary algorithm performs in terms of converging its solutions into the Pareto front and also diversifying them over the front. This is not an easy job, particularly for optimization problems with more than three objectives, dubbed many-objective optimization problems. In such problems, classic Pareto-based algorithms fail to provide sufficient selection pressure towards the Pareto front, whilst recently developed algorithms, such as decomposition-based ones, may struggle to maintain a set of well-distributed solutions on certain problems (e.g., those with irregular Pareto fronts). Another issue in some many-objective optimizers is rapidly increasing computational requirement with the number of objectives, such as hypervolume-based algorithms and shift-based density estimation (SDE) methods. In this paper, we aim to address this problem and develop an effective and efficient evolutionary algorithm (E3A) that can handle various many-objective problems. In E3A, inspired by SDE, a novel population maintenance method is proposed to select high-quality solutions in the environmental selection procedure. We conduct extensive experiments and show that E3A performs better than 11 state-of-the-art many-objective evolutionary algorithms in quickly finding a set of well-converged and well-diversified solutions.
description: 25 pages, 5 figures, to appear in Information Sciences
Valuation of cow attributes by conjoint analysis: A case study of Western Kenya
Creators: name: Makokha, Stella Nabwile
name: Karugia, Joseph Thuo
name: Staal, Steven J.
name: Oluoch-Kosura, Willis
name: Makokha, Stella Nabwile
name: Karugia, Joseph Thuo
name: Staal, Steven J.
name: Oluoch-Kosura, Willis
Publisher: name: Unknown
Year: 2007
Subjects: subject: Livestock Production/Industries
subject: Conjoint analysis
subject: valuation of cow attributes
subject: dairy production
subject: Kenya

description: Better dairy production could reduce poverty and improve nutrition in western Kenya, but the requisite technologies have not been widely adopted. This study collected dairy cow attributes from 630 households to evaluate what factors influence smallholder farmers to adopt technologies. Conjoint analysis was used to compute the marginal rate of substitution between attributes, marginal willingness to pay, and marginal willingness to accept. Two ethnic groups had the highest willingness to pay for cattle with a high milk yield and low feed requirement. The highest marginal rate of substitution for cattle with a high disease resistance and a low feed requirement was from households with off-farm income, from areas with a good agro-climate, and from areas where cattle had cultural functions. The results suggest that farmers are more likely to choose cross-bred than high grade cows, and that extension services have little effect on their adoption of dairy technology. Kenya’s breed policy and infrastructure may need to be revised to reflect farmers’ needs.
Discrete self-similarity in the formation of satellites for viscous cavity break-up
Creators: name: Fontelos, Marco A.
name: Wang, Qiming
Publisher: name: arXiv
Year: 2020
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: FOS: Physical sciences
subject: 76T06

description: The breakup of a jet of a viscous fluid with viscosity $μ_{1}$ immersed into another viscous fluid with viscosity $μ_{2}$ is considered in the limit when the viscosity ratio $λ=μ_{1}/μ_{2}$ is close to zero. We show that, in this limit, a transition from ordinary continuous selfsimilarity to discrete selfsimilarity takes place as $λ$decreases. The result being that instead of a single point breakup, the rupture of the inner jet occurs through the appearance of an infinite sequence of filaments of decreasing size that will eventually produce infinite sequences of bubbles of the inner fluid inside the outer fluid. The transition can be understood as the result of a Hopf bifurcation in the system of equations modelling the physical problem.
description: 6 pages, 10 figures
Două chestiuni în marginea textului Cum este posibilă filosofia în estul Europei.pdf
Creators: name: Vasiliu, Codrin Dinu
Publisher: name: figshare
Year: 2020
Subjects: subject: Philosophy
subject: FOS: Philosophy, ethics and religion
subject: 220307 Hermeneutic and Critical Theory

description: Este mult mai uşor să iei urma textului, să dublezi autoritatea autorului, să-ţi faci loc în dezbatere şi tocmai această uşurinţă poate produce, uneori, impresia frivolităţii. Nu pot însă rezista tentaţiei de a deschide scriitura în măcar câteva dintre datele ei importante tocmai datorită sarcinilor la care trimite exerga sa: posibilitatea faptului de a face filosofie. În această linie, din dreptul textului, îmi revin o lectură şi, deopotrivă, o tradiţie a chestiunii. O lectură a autorului care, prin manifestul şi raportul pe care le produce, tinde spre un înscris ideologic, programatic – un fapt de discurs căruia îi poţi sesiza uşor liniile atitudinale. Şi o tradiţie care, prin chiar acest program al lecturii, răzbate în aspectele ei esenţiale, „inaugurale”[1] cum se spune undeva, în această carte. Iată de ce gestul institutiv al problemei merită reluat, repus în discuţie, reintrodus în circuitul interogaţiilor care îl calibrează.
 [1] ibidem, p.5
Scalar perturbations of higher dimensional rotating and ultra-spinning black holes
Creators: name: Cardoso, Vitor
name: Siopsis, George
name: Yoshida, Shijun
Publisher: name: arXiv
Year: 2004
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Astrophysics (astro-ph)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We investigate the stability of higher dimensional rotating black holes against scalar perturbations. In particular, we make a thorough numerical and analytical analysis of six-dimensional black holes, not only in the low rotation regime but in the high rotation regime as well. Our results suggest that higher dimensional Kerr black holes are stable against scalar perturbations, even in the ultra-spinning regime.
description: 7 pages, ReVTeX 4
Asymmetric Stokes flow induced by a transverse point-force acting near a finite-sized elastic membrane
Creators: name: Daddi-Moussa-Ider, Abdallah
Publisher: name: arXiv
Year: 2020
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: Soft Condensed Matter (cond-mat.soft)
subject: Classical Physics (physics.class-ph)
subject: FOS: Physical sciences

description: A deep understanding of the physical interactions between nanoparticles and target cell membranes is important in designing efficient nanocarrier systems for drug delivery applications. Here, we present a theoretical framework to describe the hydrodynamic flow field induced by a point-force singularity (Stokeslet) directed parallel to a finite-sized elastic membrane endowed with shear and bending rigidities. We formulate the elastohydrodynamic problem as a mixed-boundary-value problem, which we then reduce into a well-behaved system of integro-differential equations. It follows that shear and bending linearly decouple so that the solution of the overall flow problem can be obtained by linear superposition of the contributions arising from these modes of deformation. Additionally, we probe the effect of the membrane on the hydrodynamic drag acting on a nearby particle, finding that, in a certain range of parameters, translational motion near an elastic membrane with only energetic resistance toward shear can, surprisingly, be sped up compared to bulk fluid. Our results may find applications in microrheological characterizations of colloidal systems near elastic confinements.
description: To appear in J. Phys. Soc. Jpn
Artificial intelligence control of a turbulent jet
Creators: name: Zhou, Yu
name: Fan, Dewei
name: Zhang, Bingfu
name: Li, Ruiying
name: Noack, Bernd R.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: FOS: Physical sciences

description: An artificial intelligence (AI) control system is developed to maximize the mixing rate of a turbulent jet. This system comprises six independently operated unsteady minijet actuators, two hot-wire sensors placed in the jet, and genetic programming for the unsupervised learning of a near-optimal control law. The ansatz of this law includes multi-frequency open-loop forcing, sensor-feedback and nonlinear combinations thereof. Mixing performance is quantified by the decay rate of the centreline mean velocity of jet. Intriguingly, the learning process of AI control discovers the classical forcings, i.e. axisymmetric, helical and flapping achievable from conventional control techniques, one by one in the order of increased performance, and finally converges to a hitherto unexplored forcing. Careful examination of the control landscape unveils typical control laws, generated in the learning process, and their evolutions. The best AI forcing produces a complex turbulent flow structure that is characterized by periodically generated mushroom structures, helical motion and oscillating jet column, all enhancing the mixing rate and vastly outperforming others. Being never reported before, this flow structure is examined in various aspects, including the velocity spectra, mean and fluctuating velocity fields and their downstream evolution, and flow visualization images in three orthogonal planes, all compared with other classical flow structures. Along with the knowledge of the minijet-produced flow and its effect on the initial condition of the main jet, these aspects cast valuable insight into the physics behind the highly effective mixing of this newly found flow structure. The results point to the great potential of AI in conquering the vast opportunity space of control laws for many actuators and sensors and in optimizing turbulence.
description: 44 pages, 24 figures
Typical entanglement of stabilizer states
Creators: name: Smith, Graeme
name: Leung, Debbie
Publisher: name: arXiv
Year: 2005
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: How entangled is a randomly chosen bipartite stabilizer state? We show that if the number of qubits each party holds is large the state will be close to maximally entangled with probability exponentially close to one. We provide a similar tight characterization of the entanglement present in the maximally mixed state of a randomly chosen stabilizer code. Finally, we show that typically very few GHZ states can be extracted from a random multipartite stabilizer state via local unitary operations. Our main tool is a new concentration inequality which bounds deviations from the mean of random variables which are naturally defined on the Clifford group.
description: Final version, to appear in PRA. 11 pages, 1 figure
Measuring irrigation water use efficiency using stochastic production frontier: An application on citrus producing farms in Tunisia
Creators: name: Dhehibi, Boubaker
name: Lachaal, Lassaad
name: Elloumi, Mohamed
name: Messaoud, Emna B.
name: Dhehibi, Boubaker
name: Lachaal, Lassaad
name: Elloumi, Mohamed
name: Messaoud, Emna B.
Publisher: name: Unknown
Year: 2007
Subjects: subject: Resource /Energy Economics and Policy
subject: Water efficiency
subject: Stochastic frontier production function
subject: Citrus farms
subject: Tunisia

description: This paper proposes an alternative measure of irrigation water efficiency based on the concept of input-specific technical efficiency. It uses a stochastic production frontier approach, based on Battese and Coelli’s (1995) inefficiency effect model, to obtain farm-specific estimates of technical and irrigation water efficiency, and a second-stage regression approach to identify the factors that influence irrigation water efficiency differentials. This methodology was applied to a sample of 144 citrus farms in Nabeul, Tunisia. Technical efficiency varies widely, suggesting that these citrus farmers could increase their production by as much 33% by using inputs more efficiently. Mean irrigation water efficiency is similarly variable, and on average below technical efficiency, suggesting that they could produce the same quantity of citrus using the same quantity of inputs but 47% less water. Finally, the results showed that the farmer’s age, education level and agricultural training, and the farm’s size, share of productive trees and availability of water tend to affect the degree of both technical and irrigation water efficiency positively.
Magnetic dipolar interaction between hyperfine clock states in a planar alkali Bose gas
Creators: name: Zou, Y. -Q.
name: Bakkali-Hassani, B.
name: Maury, C.
name: Cerf, É. Le
name: Nascimbene, S.
name: Dalibard, J.
name: Beugnon, J.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Quantum Gases (cond-mat.quant-gas)
subject: Atomic Physics (physics.atom-ph)
subject: FOS: Physical sciences

description: In atomic systems, clock states feature a zero projection of the total angular momentum and thus a low sensitivity to magnetic fields. This makes them widely used for metrological applications like atomic fountains or gravimeters. Here, we show that a mixture of two such non-magnetic states still display magnetic dipole-dipole interactions. Using high resolution spectroscopy of a planar gas of $^{87}$Rb atoms with a controlled in-plane shape, we explore the effective isotropic and extensive character of these interactions and demonstrate their tunability. Our measurements set strong constraints on the relative values of the s-wave scattering lengths $a_{ij}$ involving the two clock states.
Mapping the direction of electron ionization to phase delay between VUV and IR laser pulses
Creators: name: Mountney, M.
name: Katsoulis, G. P.
name: Møller, S. H.
name: Jana, K.
name: Corkum, P.
name: Emmanouilidou, A.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Atomic Physics (physics.atom-ph)
subject: FOS: Physical sciences

description: We theoretically demonstrate a one-to-one mapping between the direction of electron ionization and the phase delay between a linearly polarized VUV and a circular IR laser pulse. To achieve this, we use an ultrashort VUV pulse that defines the moment in time and space when an above threshold electron is released in the IR pulse. The electron can then be accelerated to high velocities escaping in a direction completely determined by the phase delay between the two pulses. The dipole matrix element to transition from an initial bound state of the N$_2$ molecule, considered in this work, to the continuum is obtained using quantum mechanical techniques that involve computing accurate continuum molecular states. Following release of the electron in the IR pulse, we evolve classical trajectories, neglecting the Coulomb potential and accounting for quantum interference, to compute the distribution of the direction and magnitude of the final electron momentum. The concept we theoretically develop can be implemented to produce nanoscale ring currents that generate large magnetic fields.
description: 10 pages, 6 figures
Autonomous Calibration of MEMS Gyros in Consumer Portable Devices
Creators: name: Li, You
name: Georgy, Jacques
name: Niu, Xiaoji
name: Li, Qingli
name: El-Sheimy, Naser
Publisher: name: arXiv
Year: 2020
Subjects: subject: Signal Processing (eess.SP)
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: This paper presents a real-time calibration method for gyro sensors in consumer portable devices. The calibration happens automatically without the need for external equipment or user intervention. Multi-level constraints, including the pseudo-observations, the accelerometer and magnetometer measurements, and the quasi-static attitude updates, are used to make the method reliable and accurate under natural user motions. Walking tests with the Samsung Galaxy S3 and S4 smartphones showed that the method estimate promising calibration results even under challenging motion modes such as dangling and pocket, and in challenging indoor environments with frequent magnetic interferences.