First Order Logic Research Papers (original) (raw)

This article presents three studies that were designed to map the dimensions involved in g, with an emphasis of the place of selfawareness in it. The first study involved preschoolers from 3 to 7 years of age. These were examined in three domains (spatial, quantitative and categorical reasoning) with both actual tasks and tasks addressed to the awareness of the cognitive processes involved in the tasks. The second study examined 11 to 16 year olds in five domains: quantitative, causal, social reasoning, drawing, and ideational fluency. Participants solved two tasks in each domain; they were asked to evaluate their performance on each task, and they answered an inventory addressed to perceived competence in each of these five domains. The third study examined participants from 11 to 15 years of age with tasks addressed to processing efficiency and capacity, reasoning, and perceived competence in three domains (quantitative, verbal, and spatial cognition). Confirmatory factor models involving firstorder domain-specific factors, second-order process-specific factors, and a third-order general factor having very strong and more or less equal relations with the second-order factors were always found. General efficiency and domain-specific processes are accurately projected into self-awareness. The accuracy of self-awareness functions was found to develop with age. The implications of these findings for the general theory of intelligence and intellectual development are discussed. D

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- Psychology, Cognitive Science, Intelligence, Cognitive development

In this paper, we compare three observers and methods for estimation of the longitudinal and latéral velocity of the vehicle. These methods are based on the First Order Sliding Mode (FOSM), Second Order Sliding Mode (SOSM) and on the use... more

- by Aziz Naamane
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- Vehicle Dynamics, Automation, Dynamic Simulation, First-Order Logic

To uncover qualitative and quantitative patterns in a data set is a challenging task for research in the area of machine learning and data analysis. Due to the complexity of real-world data, high-order (polythetic) patterns or event associations, in addition to first-order class-dependent relationships, have to be acquired. Once the patterns of different orders are found, they should be represented in a form appropriate for further analysis and interpretation. In this paper, we propose a novel method to discover qualitative and quantitative patterns (or event associations) inherent in a data set. It uses the adjusted residual analysis in statistics to test the significance of the occurrence of a pattern candidate against its expectation. To avoid exhaustive search of all possible combinations of primary events, techniques of eliminating the impossible pattern candidates are developed. The detected patterns of different orders are then represented in an attributed hypergraph which is lucid for pattern interpretation and analysis. Test results on artificial and real-world data are discussed toward the end of the paper.

- by Andrew Wong
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- Machine Learning, Graph Theory, Motor Learning, Data Analysis

A method is presented for the recovery of optical flow. The key idea is that the local spatial structure of optical flow, with the exception of surface boundaries, is usually rather coherent and can thus be appropriately approximated by a linear vector field. According to the proposed method, the optical flow components and their first order spatial derivatives are computed

- by alessandro verri
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- Mathematics, Computer Science, Computer Vision, Linear Algebra

We show that there can be no direct first order transition between a Fermi liquid and an insulating electronic (Wigner) crystalline phase in a clean two-dimensional electron gas in a metal-oxide-semiconductor field-effect transistor (MOSFET); rather, there must always exist intermediate ``micro-emulsion'' phases, and an accompanying sequence of continuous phase transitions. Among the intermediate phases which we find are a variety of electronic liquid crystalline phases, including stripe-related analogues of classical smectics and nematics. The existence of these phases can be established in the neighborhood of the phase boundaries on the basis of an {\it asymptotically exact} analysis, and reasonable estimates can be made concerning the ranges of electron densities and device geometries in which they exist. They can occur in clean Si MOSFETs in the range of densities in which an ``apparent metal to insulator transition'' has been observed in existing experiments. We...

- by Boris Spivak
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- Magnetic field, Phase transition, First-Order Logic, Double Layer

The purpose is to propose an improved method for inverse boundary value problems. This method is presented on a model problem. It introduces a higher order problem. BEM numerical simulations highlight the efficiency, the improved accuracy, the robustness to noisy data of this new approach, as well as its ability to deblur noisy data. Keywords Cauchy problem • inverse problem • boundary values • boundary element method • regularization

- by A. Cimetière
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- Mechanical Engineering, Civil Engineering, Mathematics, Computational Mechanics

In this paper we define a suitable version of the notion of homomorphism for Kripke models of intuitionistic first-order logic and characterize theories that are preserved under images and also those that are preserved under inverse images of homomorphisms. Moreover, we define a notion of union of chain for Kripke models and define a class of formulas that is preserved in unions of chains. We also define similar classes of formulas and investigate their behavior in Kripke models. An application to intuitionistic first-order arithmetic is also given.

- by Morteza Moniri
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- Intuitionistic Logic, Pure Mathematics, First-Order Logic, First Order Logic

Performance and power are the first order design metrics for Network-on-Chips (NoCs) that have become the de-facto standard in providing scalable communication backbones for multicores/CMPs. However, NoCs can be plagued by higher power consumption and degraded throughput if the network and router are not designed properly. Towards this end, this paper proposes a novel router architecture, where we tune the frequency of a router in response to network load to manage both performance and power. We propose three dynamic frequency tuning techniques, FreqBoost, FreqThrtl and FreqTune, targeted at congestion and power management in NoCs. As enablers for these techniques, we exploit Dynamic Voltage and Frequency Scaling (DVFS) and the imbalance in a generic router pipeline through time stealing. Experiments using synthetic workloads on a 8x8 wormhole-switched mesh interconnect show that FreqBoost is a better choice for reducing average latency (maximum 40%) while, FreqThrtl provides the maximum benefits in terms of power saving and energy delay product (EDP). The FreqTune scheme is a better candidate for optimizing both performance and power, achieving on an average 36% reduction in latency, 13% savings in power (up to 24% at high load), and 40% savings (up to 70% at high load) in EDP. With application benchmarks, we observe IPC improvement up to 23% using our design. The performance and power benefits also scale for larger NoCs.

- by Asit Kumar Mishra
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- Arbitration, Power Management, Power Consumption, First-Order Logic

We analyse the key algorithms of data and information fusion from a linguistic point of view, and show that they fall into two paradigms: the primarily syntactic, and the primarily semantic. We propose an alternative grammatical paradigm which exploits the ability of grammar to combine syntactic inference with semantic representation. We generalize the concept of formal generative grammar to include multiple rule classes each having a topology and a base vocabulary. A generalized Chomsky hierarchy is defined. Analysing fusion algorithms in terms of grammatical representations, we find that most (including multiple hypothesis tracking) can be expressed in terms of conventional regular grammars. Situation analysis, however, is commonly attempted using first order predicate logic, which while expressive, is recursively enumerable and so scales badly. We argue that the core issue in situation assessment is force deployment assessment, the extraction and scoring of hypotheses of the force deployment history, each of which is a multiresolution account of the activities, groupings and interactions of force components. The force deployment history represents these relationships at multiple levels of granularity and is expressed over time and space. We provide a grammatical approach for inferring such histories, and show that they can be estimated accurately and scalably. We employ a generalized context-free grammar incorporating both sequence and multiset productions. Elaborating [D. McMichael, G. Jarrad, S. Williams, M.

- by Daniel McMichael
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- Computer Science, Combinatory Categorial Grammar, Parsing, Situation Assessment

An approach is treated for numerical integration of ordinary differential equations systems of the first order with choice of a computation scheme, ensuring the required local precision. The treatment is made on the basis of schemes of Runge-Kutta-Fehlberg type. Criteria are proposed as well as a method for the realization of the choice of an 'optimum' scheme. The effectiveness of the presented approach to problems in the field of satellite dynamics is illustrated by results from a numerical experiment. These results refer to a case when a satisfactory global stability of the solution for all treated cases is available. The effectiveness has been evaluated as good, especially when solving multi-variable problems in the sphere of simulation modelling.

- by Atanas Atanassov
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- Mathematics, Computer Science, Physics, Numerical Analysis

Temperature dependent normal modes and lattice thermal expansion of the Sr 2 B'UO 6 (B' = Ni, Co) double perovskites were investigated by Raman/infrared spectroscopies and synchrotron Xray diffraction, respectively. Monoclinic crystal structures with space group P2 1 /n were confirmed for both compounds, with no clear structural phase transition between 10 and 400 K. As predicted for this structure, the first-order Raman and infrared spectra show a plethora of active modes. In addition, the Raman spectra reveal an enhancement of the integrated area of an oxygen stretching mode, which is also observed in higher-order Raman modes, and an anomalous softening of ~1 cm -1 upon cooling below T* ~ 300 K. In contrast, the infrared spectra show conventional temperature dependence. The band profile phonon anomalies are possibly related to an unspecified electronic property of Sr 2 B'UO 6 (B' = Ni, Co).

This paper deals with the rough design of a Double-Stator Axial Flux Permanent Magnet Machine (DSAFPM) for a rim-driven Marine Current Turbine (MCT). The DSAFPM machine will be compared to a previously developed and realized Radial Flux Permanent Magnet Machine (RFPM); given the same rim-driven MCT specifications. For that purpose, a first-order electromagnetic design model and a thermal one are developed and used to compare active part mass, cost, and thermal behavior of the two machines.

- by M. Benbouzid
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- Copper, Iron, First-Order Logic, Generators

Sunflower is a traditional crop which can be used for the production of bioenergy and liquid biofuels. A study of the pyrolytic behaviour of sunflower residues at temperatures from 300 to 600°C has been carried out. The experiments were performed in a captive sample reactor under atmospheric pressure and helium as sweeping gas. The yields of the derived pyrolysis products were determined in relation to temperature, with constant sweeping gas flow of 50 cm 3 min À1 and heating rate of 40°C s À1 . The maximum gas yield of around 53 wt.% was obtained at 500°C, whereas maximum oil yield of about 21 wt.% was obtained at 400°C. A simple first order kinetic model has been applied for the devolatilization of biomass. Kinetic constants have been estimated: E = 78.15 kJ mol À1 ; k 0 = 1.03 · 10 3 s À1 .

- by Efthymios Kantarelis
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- Kinetics, Multidisciplinary, Energy Metabolism, Greece

Empirically, co-skewness of asset returns seems to explain a substantial part of the cross-sectional variation of mean return not explained by beta. This finding is typically interpreted in terms of a risk averse representative investor with a cubic utility function. This paper questions this interpretation. We show that the empirical tests fail to impose risk aversion and the implied utility function takes an inverse S-shape. Unfortunately, the first-order conditions are not sufficient to guarantee that the market portfolio is the global maximum for this utility function, and our results suggest that the market portfolio is more likely to represent the global minimum. In addition, if we do impose risk aversion, then co-skewness has minimal explanatory power.

- by Haim Levy
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- Applied Mathematics, Asset Pricing, Risk Aversion, First-Order Logic
- by Le Binh
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- First-Order Logic, Optical physics, Tunable Filter, First Order Logic

Word sense disambiguation (WSD) is the problem of determining the sense of a multi-sense word in a given context. It is one of the important processes needed for natural language processing applications. Inductive Logic Programming (ILP) is the area of artificial intelligence which contains machine learning and logic programming. It aims to build first- order theories from examples and background knowledge, which are also represented by first- order clauses. The richness of first order logic employed in ILP can hopefully provide advantages for NLP applications such as WSD. In this study, a corpus-based WSD application is improved by using ILP.

Our paper examines how a firm's corporate governance relates to the liquidity (i.e., bidask spread) of its stock. In particular, we focus on how voluntary disclosure, analyst coverage, and adverse selection among investors mediate this relation. Our results show that better corporate governance, in terms of greater board independence and greater institutional monitoring, improves liquidity though more voluntary disclosure, greater analyst coverage, and lower adverse selection. The effects of these mediating mechanisms differ in magnitude. Specifically, we find that the key reason to expect better corporate governance to be associated with improved liquidity is reduced adverse selection. This finding is consistent with the argument that the first order effect of better corporate governance is to constrain agency problems such as insider trading and selective disclosure to some investors, which, in turn, could affect stock liquidity.

- by Kevin Ow Yong
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- Corporate Governance, Financial management, Adverse Selection, Insider Trading

Alachlor, metolachlor, atrazine, cyanazine, simazine and terbuthylazine were applied to plots containing a drainage system in order to determine the concentrations of parent compounds and their metabolites in soil and in leachate samples. The results indicated that all these herbicides disappeared substantially in the soil surface layer following first order kinetics. In the surface soil, the disappearance times of 50% of the concentration (DTSOs) for terbuthylazine, atrazine, metolachlor, cyanazine, simazine and alachlor were 44,35, 34, 28, 28 and 20 days, respectively.

- by Paola Bottoni
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- Kinetics, Multidisciplinary, First-Order Logic, First Order Logic

Subducting slabs provide the main driving force for plate motion and flow in the Earth's mantle 1-4 , and geodynamic, seismic and geochemical studies offer insight into slab dynamics and subductioninduced flow 3-15 . Most previous geodynamic studies treat subduction zones as either infinite in trench-parallel extent 3,5,6 (that is, two-dimensional) or finite in width but fixed in space 7,16 . Subduction zones and their associated slabs are, however, limited in lateral extent (250-7,400 km) and their three-dimensional geometry evolves over time. Here we show that slab width controls two first-order features of plate tectonics-the curvature of subduction zones and their tendency to retreat backwards with time. Using three-dimensional numerical simulations of free subduction, we show that trench migration rate is inversely related to slab width and depends on proximity to a lateral slab edge. These results are young (#5 Myr), have a short slab (#150 km) and, together with collision zones, have been excluded from the trench migration calculations in . Trench migration rates for incipient subduction zones are presented in .

- by W. Schellart and +1
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- Convex Geometry, Time Use, Multidisciplinary, Nature

In this paper, we present new version of numerically stable fast recursive least squares (NS-FRLS) algorithm. This new version is obtained by using some redundant formulae of the fast recursive least squares (FRLS) algorithms. Numerical stabilization is achieved by using a propagation model of first order of the numerical errors. A theoretical justification for this version is presented by formulating new conditions on the forgetting factor. An advanced comparative method is used to study the efficiency of this new version relatively to RLS algorithm by calculating their normalized square norm gain error (NGE). We provide a theoretical justification for this version by formulating new conditions on forgetting factor. It will be followed by an analytical analyze of the convergence of this version and we show, both theoretically and experimentally, their robustness. The simulation over a very long duration for a stationary signal did not reveal any tendency to divergence.

- by Daoud BERKANI
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- Adaptive Filter, First-Order Logic, Comparative method, First Order Logic

Silica-alumina in the form of diethylamine (deam)-, dimethylamine (dmam)-, ethylamine (earn)-, ammonia (amm)-and aniline (an)-copper (II) complexes as well as deam-cobalt (II) complex have been used as potentially active catalysts for HzOz decomposition in an aqueous medium. The reaction was first order with respect to the H202 concentration and the rate constants (per g of dry silica-alumina) were determined. A coloured compound, a peroxo-metal complex, which formed at the beginning of the reaction in each case, was found to contain the catalytically active species. The activation energy and the change in the entropy of activation increased with the basicity of the ligands in the following order: an < amm < earn < dmam < deam, which is also the probability sequence for the formation of the activated complex. A reaction mechanism was proposed.

- by Ali H Gemeay
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- Kinetics, Silica, First-Order Logic, CHEMICAL SCIENCES

Moisture is one of the most deteriorating factors of buildings. The deteriorating effect of moisture occurs mainly during the drying phase, and not in the wetting phase. Appropriate parameters of the drying kinetics are required for the building materials. Environmental factors, such as air temperature, air humidity, and air velocity affect drying. An experimental air dryer of controlled drying air conditions was used to investigate the drying performance of 4 stone materials, 2 bricks and 7 plasters. Drying kinetics was examined at 4 air temperatures, 6 air humidities, and 3 air velocities. A first-order kinetics model was obtained, in which the drying time constant was a function of the drying conditions, and the equilibrium material moisture content was described by the Oswin equation. The parameters of the proposed model were found to be affected strongly by the material and the drying air conditions. The results obtained are very useful in selecting the appropriate plaster to protect existing historic buildings.

- by Maria Karoglou
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- Chemical Engineering, Drying Technology, Air Conditioning, First-Order Logic

The inactivation kinetics of polygalacturonase (PG) in tomato juice was studied during thermal and high-pressureythermal processing. In the temperature range of 55-70 8C the thermal inactivation of polygalacturonase in tomato juice followed a fractional conversion model, with a thermostable fraction of approximately 14%. Under conditions of combined high-pressurey thermal processing, 200-550 MPay5-50 8C, PG inactivation presented first order kinetics. A mathematical model to describe the inactivation rate constant as a function of pressure and temperature was formulated. Industrial relevance: Polygalacturonase is responsible for the decrease of viscosity in tomato-based products. However, little research on thermal and high pressureythermal inactivation kinetics of tomato Polygalacturonase has been reported. This research clearly shows that it is possible to selectively inactivate PG by high pressureythermal processing without applying high temperatures. This leads to tomato-based products with improved functional properties while other quality attributes (color, flavor, nutritional value) are maintained. ᮊ Industrial relevance: The data of the research presented clearly suggest that polygalacturonase can be inactivated at ambient temperatures when applying a combined pressureytemperature treatment. The first order kinetic model established for high pressure inactivation proved valid, and after pressure treatment, in contrast to thermal processing alone, no stable fraction of polygalacturonase was observed. This can lead to processing of tomato products of high quality due to the now possible low temperature treatment.

- by Ly Binh
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- Engineering, High Pressure, Kinetics, Biological Sciences

pH is one of the key parameters that determines heavy metal mobility in soils, sediments and waste materials. In many respects leaching behaviour as reflected by the pH stat leaching tests provide a better means of assessing environmental impact than analysis of total elemental composition. This paper discusses the use of pH stat leaching tests as a tool to assess the potential mobilisation of trace metals from soils, sediments and waste materials. The possibilities of pH stat leaching tests are illustrated by means of different examples.

- by Valerie Cappuyns
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- Engineering, Thermodynamics, Soil, Kinetics

In the near future, several space missions are scheduled, which will closely investigate short-period comets. Some of these (e.g., ROSETTA) will also deliver landing probes for in situ investigations of the nucleus' surface. Therefore there is now renewed interest in the structure and behavior of cometary surface layers. In this paper we discuss in detail some basic features that may constitute the "landscape" of a comet nucleus: gas outflow from gaps and holes is considered, based on a fundamental kinetic approach and previous work. Both the gas emission from icedominated walls and the outflow through "dusty" channels with a sublimating icy bottom are calculated. We attribute special emphasis to the influence of recondensation on the energy balance. It is found that-assuming realistic temperature profiles as a function of depth-there exist areas of net recondensation along the walls of ice channels, which might act as interior heat sources. Furthermore, our Monte Carlo model is applied to interpret some results obtained in various comet simulation (KOSI) experiments, which were performed in the years 1989-1993 with porous ice samples irradiated in the space simulator at DLR Cologne/Germany. It was found that when using the measured temperature profile inside the ice sample Monte Carlo calculations predict that the recondensation region coincides with the region of the steepest temperature gradient. Another result relevant for the understanding of cometary surface phenomena is that at least in first order the temperature difference between a sublimating ice front and the surface temperature of an overlying porous dust mantle or nonvolatile cohesive residuum is almost independent of the thickness of the nonvolatile layer.

- by N. Kömle
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- Geochemistry, Geophysics, Kinetics, Monte Carlo

Labeled transition systems are key structures for modeling computation. In this paper, we show how they lend themselves to ordinary logical analysis (without any special new formalisms), by introducing their standard first-order theory. This perspective enables us to raise several basic model-theoretic questions of definability, axiomatization and preservation for various notions of process equivalence found in the computational literature, and answer them using well-known logical techniques (including the Compactness theorem, Saturation and Ehrenfeucht games). Moreover, we consider what happens to this general theory when one restricts attention to special classes of transition systems (in particular, finite ones), as well as extended logical languages (in particular, infinitary firstorder logic). We hope that this puts standard logical formalisms on the map as a serious option for a theory of computational processes. As a side benefit, our approach increases comparability with several other existing formalisms over labeled transition systems (such as Process Algebra or Modal Logic). We provide some pointers to this effect, too.

- by Johan van Benthem
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- Cognitive Science, Modal Logic, Model Theory, Philosophy

The efficacy of ultraviolet germicidal irradiation (UVGI) for inactivating airborne fungal spores and bacterial vegetative cells was evaluated under three configurations-intrinsic, upper-room air, and induct. Correspondingly, experiments were performed in (1) a pilot-scale chamber (0.8 m 3), fitted with four corner UV lamps that irradiated the entire chamber (average UV fluence rate 10.6 ± 0.8 µJ s −1 cm −2); (2) a full-scale room (87 m 3), fitted with a UVGI system that irradiated the top 30 cm of the room (5 fixtures, 216 W total lamp power, average upper-zone UV fluence rate 26 ± 1 µJ s −1 cm −2); and (3) the supply air duct of a heating ventilation and airconditioning (HVAC) system. Fungal spores of Aspergillus versicolor and vegetative cells of bacterium Mycobacterium parafortuitum were aerosolized continuously such that their numbers and physiologic state were comparable both with and without the UVGI lamps operating. The Z value (UVGI inactivation rate normalized to UVGI fluence rate) was estimated to be 1.2 ± 0.4 × 10 −4 cm 2 µJ −1 for aerosolized A. versicolor. Upper-room air UVGI inactivated culturable airborne fungal spores with a first-order rate constant of 0.4 ± 0.2 h −1. Ultraviolet lamps enclosed in ventilation system ductwork inactivated fungal spores and vegetative bacterial cells at single-pass efficiencies of 75% and 87%, respectively, at an air stream velocity of 2.2 m s −1. There was no detected inactivation of fungal spores and vegetative bacterial cells at an air stream velocity of 5.1 m s −1 .

- by Mark Hernandez
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- Environmental Engineering, Ultraviolet, First-Order Logic, Hvac System

A series of numerical schemes: first-order upstream, Lax -Friedrichs; second-order upstream, central difference, Lax-Wendroff, Beam-Warming, Fromm; third-order QUICK, QUICKEST and high resolution flux-corrected transport and total variation diminishing (TVD) methods are compared for onedimensional convection-diffusion problems. Numerical results show that the modified TVD Lax-Friedrichs method is the most competent method for convectively dominated problems with a steep spatial gradient of the variables.

- by Kolumban Hutter
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- Engineering, Convection, Computational Fluid Dynamics, Comparative Study

Nitrous and nitric acids form in aqueous solutions exposed to a gliding arc discharge burning in humid air. The anions interfere when the concentration of particular solutes such as pollutants must be determined. In particular they falsify the COD measurements and spectral investigations and thus the efficiency of the plasma treatment in pollutant abatement. The nitrite anions must be thus removed, which require specific reagents.

- by Mohamed Belhadj and +1
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- Chemical Engineering, Analytical Chemistry, Kinetics, Separation

This paper offers two main contributions. On the one hand, it establishes a general formal framework for developing a foundational ontology of socially constructed entities, in the broadest sense of this notion; on the other hand, it further contributes to understanding the ontological nature of roles. The key choice here is to put all social entities in the domain of discourse: besides social individuals, we also consider 'reified' social concepts and roles, as well as their descriptions, i.e, the 'social conventions' or 'contexts' that define them. This allows us to formally characterize in a first-order theory the relationships among all these entities.

- by Emanuele Bottazzi
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- Computer Science, Applied Ontology, Formal Ontology, Social Ontology

Salmonella spp. has recently been involved in a number of food-borne outbreaks with a high impact on pharmaceuticals, food safety, and the economy. These outbreaks have increased the need to understand the behavior of this microorganism under conventional and new technologies applied to reduce its presence in food products. In the last twenty years, a number of emerging food processing technologies have been proposed as alternatives to thermal food processing. Studies have proven that these technologies ensure microbial inactivation while producing foods with better nutritional and sensory characteristics. Salmonella is one of the target microorganisms under study for these novel technologies showing encouraging results. Salmonella inactivation using conventional and novel technologies often does not follow first order kinetics, posing the need for models that adequately describe its survival curves and have predictive ability. This manuscript presents a summary of some of the emerging technologies used to inactivate Salmonella species in different food products and model systems, along with their inactivation patterns. It also reviews the models currently proposed to describe and estimate Salmonella inactivation under conventional thermal treatments and their applicability and limitations to characterize the survival curves obtained during exposure to novel technologies.

- by Maria Corradini
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- Chemical Engineering, Kinetics, Food, Mathematical Modeling

Conformational stability Xenon and krypton solutions Infrared and Raman spectra r 0 Structural parameters Ab initio calculations Ethylisocyanate a b s t r a c t Variable temperature (À55 to À155°C) studies of the infrared spectra (400-3500 cm À1 ) of ethylisocyanate, CH 3 CH 2 NCO, dissolved in liquid xenon and krypton have been recorded. Additionally the infrared spectra of the gas and solid have been re-investigated. These spectroscopic data indicate two conformers in the fluid states which are the cis and trans forms with a large proportion of molecules in the gas phase at ambient temperature in the excited states of the NCO torsional mode which has a very low barrier to conformational interchange. Variable temperature (À110 to À155°C) studies of krypton solutions were carried out and by using two conformer pairs, an enthalpy difference of 100 ± 4 cm À1 (1.20 ± 0.05 kJ/mol) was obtained with the cis conformer the more stable form. To aid in the analyses of the vibrational and rotational spectra, ab initio calculations have been carried out by the perturbation method to the second order (MP2) with full electron correlation using a variety of basis sets up to 6-311+G(2df,2pd) and cc-PVQZ. With the basis sets 6-311+G(2d,2p) and larger, the barrier at the cis position ranged from a low value of 11 cm À1 to a high value of 31 cm À1 with a value of 19 cm À1 from the largest basis set of cc-PVQZ. Thus, the gauche well is probably so shallow that it does not contain a bound vibrational state. This results in the cis conformer as the most stable form which is consistent with the experimental rotational and vibrational data. The predicted energy difference from these calculations between the cis conformer and the transitional-state skew form is $100 cm À1 which is consistent with the assigned microwave lines for four excited states of the NCO torsion. Density functional theory calculation by the B3LYP method with many of the same basis sets provided little information. By utilizing the previously reported microwave rotational constants with the structural parameters predicted by the ab initio MP2(full)/6-311+G(d,p) calculations, adjusted r 0 structural parameters have been obtained for the cis form. The determined heavy atom parameters are: r(C@N) = 1.211(5), r(C@O) = 1.167(5), r(CAN) = 1.448(5), r(CAC) = 1.516(5) Å for the distances and angles of \CCN = 112.6(5), \CNC = 137.5(5), \NCO = 172.9(5)°. The centrifugal distortion constants, dipole moments, conformational stability, vibrational frequencies, infrared intensities and Raman activities have been predicted from ab initio calculations and compared to experimental quantities when available. These results are compared to the corresponding quantities of some similar molecules.

The analysis and design of high-order phase-locked loops (PLLs) is difficult. A novel approach is presented which allows high-order loops to be viewed as a natural extension of lowerorder ones. Type I low-order PLLs are considered a starting point for the design of higher type, higher-order PLLs. Starting with lower-order PLLs not only permits a comprehensive classification of all practical kinds of PLLs but also facilitates their design from a more intuitive perspective. The model presented, based on the loop filter composed of several nested first-order feedback loops, has been implemented and tested in Simulink w , confirming the ideas presented.

- by A. Carlosena
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- Feedback, Phase Locked Loop, First-Order Logic, Seismic analysis and design

Dynamic speckle or biospeckle is a phenomenon generated by laser light scattering in biological tissues and it is also present in some industrial processes where the surfaces exhibit some kind of activity. In this work we present some results of a numerical model to describe the time history of a dynamic speckle pattern considering very simplified situations. In this case

- by Hector Rabal and +1
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- First-Order Logic, Optical physics, First Order Logic, Gray Level Co-occurrence Matrix

In this article we use Adomian decomposition method, which is a well-known method for solving functional equations now-a-days, to solve systems of differential equations of the first order and an ordinary differential equation of any order by converting it into a system of differential of the order one. Theoretical considerations are being discussed, and convergence of the method for theses systems is addressed. Some examples are presented to show the ability of the method for linear and non-linear systems of differential equations.

More than 40 years the correspondence between modal logic and first-order logic, when they are interpreted in relational structures, is on the main stream of the investigations of many modal logicians. The most interesting in this direction is a series of results on modal and first-order definability proved by Chagrova in the 1990s. In particular, from them it follows the undecidability of both types de-finability. These results stimulate creating of different algorithms which in many cases succeed to find first-order equivalent for any formula from a reach set of modal formulas. On the other hand, Balbiani and Tinchev have proved for sev-eral modal languages that both definability problems, restricted to the class of all partitions, are decidable and have found their complexity. A straightforward trans-fer of these results to the case of modal language with two modalities interpreted by equivalence relations is impossible. Moreover, the correspondence problem is undecidable in the ...

- by Tinko Tinchev and +1
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- Modal Logic, First-Order Logic, First Order Logic, Correspondence Problem

Corrosion in pipelines has been probabilistically modeled. However, the potential effect of spatial correlation of corrosion defects, in several segments of a pipeline, on its failure probability has not received much attention. In this paper, several degrees of spatial correlation are assumed for the corrosion in determined segments of a pipeline and their effects on the global reliability are examined. The pipeline is assumed to be a series system. The failure mode is considered to be controlled by the stresses due to internal pressure and the presence of corrosion. Component reliability is calculated by First Order Second Moment approximations. First order bounds are used to define the limits for the global failure probability by assuming first, either no correlation (independent pipeline segments) and, secondly, perfect correlation between segments. Then, second order bounds are estimated to improve the calculation of the failure probability by including the correlation coefficients mentioned above. The correlation degree between failure modes at two pipeline segments increases with the degree of correlation of the corrosion initial depths located at these segments. Also, for a correlation coefficient between corrosion depths larger than 0.6, its contribution to the correlation between failure modes becomes significant and, therefore, should be accounted for. When the specific correlation degree between corrosion defects at adjacent pipeline segments is considered in the calculation of an example pipeline failure probability, this probability is narrowly bounded between 0.58 and 0.59, as compared to the usual practice where this correlation is assumed to be either 0 or 1 for which the failure probability is bounded between 0.49 and 0.79. The formulation may be used to set optimal maintenance schedules for pipelines under corrosion.

- by OSCAR FERNANDO TOVAR MACIAS
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- Mechanical Engineering, Monte Carlo Simulation, Modeling, Pipeline

Objective: Automatic comparisons of sound duration in auditory sensory memory are typically investigated by comparing event-related potentials (ERPs) to standard and deviant stimuli presented in oddball blocks. Deviants elicit mismatch negativity (MMN). This procedure might overestimate an MMN contribution reflecting automatic sensory memory processes because of differential states of refractoriness of respectively recruited neural populations [Neuroreport 1996;7:3005; Psychophysiology 2001;38:723]. Here, memory-comparison-based Duration MMN contributions were investigated using various experimental protocols.

- by Erich Schröger
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- Engineering, Electrophysiology, Auditory Perception, Cognition

Visual motion is sensed by low-level (energy-based) and high-level (feature-based) mechanisms. Ocular following responses (OFR) were elicited in humans by applying horizontal motion to vertical square-wave gratings lacking the fundamental ("missing fundamental stimulus"). Motion consisted of successive 1/4-wavelength steps, so the features and 4n+1 harmonics (where n=integer) shifted forwards, whereas the 4n-1 harmonics--including the strongest Fourier component (the 3rd harmonic)--shifted backwards (spatial aliasing). Initial OFR, recorded with the electromagnetic search coil technique, were always in the direction of the 3rd harmonic, e.g., leftward steps resulted in rightward OFR. Thus, the earliest OFR were strongly dependent on the motion of the major Fourier component, consistent with early spatio-temporal filtering prior to motion detection, as in the well-known energy model of motion analysis.

- by kevin Chen
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- Psychophysics, Motion perception, Motion Analysis, Vision

The dilute acid hydrolysis of grass and cellulose with phosphoric acid was undertaken in a microwave reactor system. The experimental data and reaction kinetic analysis indicate that this is a potential process for cellulose and hemi-cellulose hydrolysis, due to a rapid hydrolysis reaction at moderate temperatures. The optimum conditions for grass hydrolysis were found to be 2.5% phosphoric acid at a temperature of 1758C. It was found that sugar degradation occurred at acid concentrations greater than 2.5% (v/v) and temperatures greater than 1758C. In a further series of experiments, the kinetics of dilute acid hydrolysis of cellulose was investigated varying phosphoric acid concentration and reaction temperatures. The experimental data indicate that the use of microwave technology can successfully facilitate dilute acid hydrolysis of cellulose allowing high yields of glucose in short reaction times. The optimum conditions gave a yield of 90% glucose. A pseudo-homogeneous consecutive first order reaction was assumed and the reaction rate constants were calculated as: k 1 ¼ 0.0813 s 21 ; k 2 ¼ 0.0075 s 21 , which compare favourably with reaction rate constants found in conventional non-microwave reaction systems. The kinetic analysis would indicate that the primary advantages of employing microwave heating were to: achieve a high rate constant at moderate temperatures: and to prevent 'hot spot' formation within the reactor, which would have cause localised degradation of glucose.

- by Mohammad Ahmad
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- Chemical Engineering, Kinetics, Bioenergy, Biofuels

- by Mohammad Ahmad
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- Chemical Engineering, Kinetics, Bioenergy, Biofuels

The first wave of behavior therapy countered the excesses and scientific weakness of existing nonempirical clinical traditions through empirically studied first-order change efforts linked to behavioral principles targeting directly relevant clinical targets. The second wave was characterized by similar direct change efforts guided by social learning and cognitive principles that included cognitive in addition to behavioral and emotive targets. Various factors seem to have set the stage for a third wave, including anomalies in the current literature and philosophical changes. Acceptance and Commitment Therapy (ACT) is one of a number of new interventions from both behavioral and cognitive wings that seem to be moving the field in a different direction. ACT is explicitly contextualistic and is based on a basic experimental analysis of human language and cognition, Relational Frame Theory (RFF). RFT explains why cognitive fusion and experiential avoidance are both ubiquitous and harmful. ACT targets these processes and is producing supportive data both at the process and outcome level. The third-wave treatments are characterized by openness to older clinical traditions, a focus on second order and contextual change, an emphasis of function over form, and the construction of flexible and effective repertoires, among other features. They build on the first-and second-wave treatments, but seem to be carrying the behavior therapy tradition forward into new territory.

- by Steven Hayes
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- Psychology, Behavior Modification, Socialization, Treatment

Dyes are usually present in trace quantities in the treated effluents of many industries. The effectiveness of adsorption for dye removal from wastewaters has made it an ideal alternative to other expensive treatment methods. This study investigates the potential use of Indian Rosewood (Dalbergia sissoo) sawdust, pretreated with formaldehyde and sulphuric acid, for the removal of methylene blue dye from simulated wastewater. The effects of different system variables, viz., adsorbent dosage, initial dye concentration, pH and contact time were studied. The results showed that as the amount of the adsorbent was increased, the percentage of dye removal increased accordingly. Higher adsorption percentages were observed at lower concentrations of methylene blue. Optimum pH value for dye adsorption was determined as 7.0 for both the adsorbents. Maximum dye was sequestered within 30 min after the beginning for every experiment. The adsorption of methylene blue followed a first order rate equation and fit the Lagergren equation well. Similar experiments were carried out with commercially available activated carbon to compare the results. Sulphuric acid treated sawdust or formaldehyde treated sawdust of Indian Rosewood can be attractive options for dye removal from dilute industrial effluents.

- by Kushal Brahmapal
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- Chemical Engineering, Kinetics, Water Pollution, Adsorption

Sulphur dioxide is used as a pre-treatment to facilitate drying, improve product quality and extend the shelf life of apricots. During storage, SO 2 losses are observed, thus reducing the effect of this agent. The aim of this paper is to analyze the evolution of SO 2 content in dried apricots packaged in different types of containers, namely glass and polypropylene trays thermosealed with different films (oriented polyamide OPA þ polyethylene PE and polyamide PA þ polypropylene PP). The packaging atmosphere was air in all cases. Storage was carried out at constant temperature: 5, 15, 25 and 35 C. Stored samples were analysed periodically over 12 months. In order to model the SO 2 losses, two empirical kinetic models were tested: these models assimilate this process to a first order irreversible and a first order reversible kinetics. The explained variance being higher than 94% in all cases, but only the reversible kinetics is able to depict the residual SO 2 observed.

- by Gonzalo Miranda
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- Kinetics, Animal Production, SHELF LIFE, Polypropylene

Over the last three decades the first-order correlation in morphology and orientation of seamount trails has been called upon to support the concept of a ''fixed'' Pacific hot spot frame of reference and to explain the Hawaii-Emperor bend (HEB) by a dramatic change in Pacific plate motion. In this paper, however, we present 40 Ar/ 39 Ar ages for the Gilbert Ridge and Tokelau Seamounts (Pacific) that show similar changes or bends in their orientation, but at different geological times, up to 20 Myr earlier than the HEB. Changes in Pacific plate motion alone cannot explain these observations, because these asynchronous bends should have been reflected in the morphology of each of these seamount trails. Together with the lack of (linear) age progressions and inconsistent apparent local plate velocities of 131 and 87 mm/yr, we rule out a fixed hot spot origin for the Gilbert Ridge and Tokelau seamount trails. Instead we invoke secondary or alternate processes to explain the complex age systematics and morphologies in these seamount trails. We propose here that the HEB-type bends in these seamount trails were likely formed by short-term ''jerk-like'' plate extensions in the studied southwestern region of the Pacific plate, reactivating a preconditioned lithosphere that can be characterized by a complex structure and precursory magmatic impingements. The remarkable differences observed in these colinear seamount trails fundamentally question the existence of HEB-type bends in the formation of Pacific volcanic lineaments. They also show us that applying geometric and morphologic observations alone is insufficient in constraining past plate motions. Nevertheless, the need and search for alternate volcano-tectonic mechanisms offer opportunities to better understand intraplate volcanism in general.

- by Jason Phipps Morgan
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- Earth Sciences, Geology, Physical sciences, Seamounts

The kinetic model of the hydrolysis of lactose with a ␤-galactosidase from Kluyveromyces fragilis immobilized on a commercial silica-alumina (KA-3, from Südchemie) has been determined. A wide experimental range of the main variables has been employed: temperature, concentrations of substrate, and products and concentration of enzyme. The runs were performed in a complex buffer with the salt composition of milk. The effect of pH and temperature on the stability and the activity of the enzyme have been studied. The optimum pH for the enzyme activity was, approximately, seven. The immobilized enzyme was more stable than the free one at acidic pH, but more instable at basic pH. The maximum temperature used for the hydrolysis runs performed to select the kinetic model was 40°C, so inactivation of the enzyme during the kinetic runs has been avoided. Agitation, concentration of enzyme in the solid and particle size were selected to ensure that the overall rate was that of the chemical reaction. Eleven kinetic models were proposed to fit experimental data, from first order to more complex ones, such as those taking into account inhibition by one of the compounds involved in the hydrolysis reaction. Applying statistical and physical criteria, a Michaelis-Menten model with a competitive inhibition by galactose has been selected. The model is able to fit the experimental data correctly in the wide experimental range studied. Finally, the model obtained is compared to the one selected in a previous work for the hydrolysis of lactose with the free enzyme.

- by Aurora Santos
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- Kinetics, Environmental Biotechnology, Silica, First-Order Logic

Two-electrode cells with a Pt or boron-doped diamond anode and an air-diffusion cathode for H 2 O 2 electrogeneration, and four-electrode combined cells containing the above pair of electrodes coupled in parallel to a Pt anode and a carbon-felt cathode, have been used to degrade the pharmaceutical ␤blocker atenolol by electro-Fenton and photoelectro-Fenton methods. In these processes, organics are mainly oxidized with hydroxyl radical ( • OH) formed simultaneously at the anode surface from water oxidation and from Fenton's reaction between added catalytic Fe 2+ and electrogenerated H 2 O 2 . Aromatic intermediates such as 4-hydroxyphenylacetamide and p-benzoquinone and generated carboxylic acids such as maleic, fumaric, tartaric, tartronic, glycolic, formic, oxalic and oxamic are detected and quantified by high-performance liquid chromatography. Compared with the single cells, the corresponding novel four-electrode combined systems enhance strongly the mineralization rate of atenolol in electro-Fenton because of the fast Fe 2+ regeneration at the carbon-felt cathode favoring: (i) the production of more amounts of • OH from Fenton's reaction that destroy more rapidly aromatic pollutants and (ii) the formation of Fe(II) complexes with final carboxylic acids such as oxalic and oxamic, which are more quickly oxidized with • OH. In photoelectro-Fenton, both single and combined cells show a quite similar oxidation power giving almost total mineralization as a result of the parallel quick photolysis of Fe(III) and/or Fe(II) complexes under UVA irradiation. The efficient regeneration of Fe 2+ with larger • OH production in the combined cells causes a quicker atenolol decay, which always follows a pseudo first-order reaction. NH 4 + and in smaller proportion NO 3 − are always released to the medium.

- by José Arias Garrido
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- Environmental Engineering, Chemical Engineering, Kinetics, Pharmaceuticals