998 resultados para Interaction parameter


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In this Thesis the interaction of an electromagnetic field and matter is studied from various aspects in the general framework of cold atoms. Our subjects cover a wide spectrum of phenomena ranging from semiclassical few-level models to fully quantum mechanical interaction with structured reservoirs leading to non-Markovian open quantum system dynamics. Within closed quantum systems, we propose a selective method to manipulate the motional state of atoms in a time-dependent double-well potential and interpret the method in terms of adiabatic processes. Also, we derive a simple wave-packet model, based on distributions of generalized eigenstates, explaining the finite visibility of interference in overlapping continuous-wave atom lasers. In the context of open quantum systems, we develop an unraveling of non-Markovian dynamics in terms of piecewise deterministic quantum jump processes confined in the Hilbert space of the reduced system - the non-Markovian quantum jump method. As examples, we apply it for simple 2- and 3-level systems interacting with a structured reservoir. Also, in the context of ion-cavity QED we study the entanglement generation based on collective Dicke modes in experimentally realistic conditions including photonic losses and an atomic spontaneous decay.

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In the fierce competition of today‟s business world an organization‟s capacity to learn maybe its only competitive advantage. This research aims at increasing the understanding on how organizational learning from the customer happens in technology companies. In doing so it provides a synthesized definition of organizational learning and investigates processes of organizational learning within technology companies. A qualitative research method and in-depth interviews with different sized high technology companies, as applied here, enables in-depth study of the learning processes. Research contributes to the understanding of what type of knowledge firms acquire, how new knowledge is transferred and used in a learning firm‟s routines and processes. Research findings show that SMEs and large size companies also, depending on their position in the software value chain, consider different knowledge types as most important and that they use different learning methods to acquire knowledge from their customers.

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This work aimed to evaluate root colonization and interaction among isolates of rhizobacteria and eucalypt species. The method used to evaluate "in vitro" root colonization was able to indicate if the effect was benefic or deleterious allowing to pre-select isolates as potential growth promoter. There was interaction among isolates of rhizobacteria and Eucalyptus species for seed germinating and seedling growth. MF2 (Pseudomonas sp.) was the best rhizobacteria isolate for growth promotion of E. cloeziana e E. grandis. S1 (Bacillus subtilis) was the most effective for E. globulus, and Ca (Pseudomonas fulva), MF2 (Pseudomonas sp.), CIIb (Stenotrophomonas maltophilia) and S2 (B. subtilis) were the most promising isolates for the E. urophylla.

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ABSTRACT This study aimed to verify the differences in radiation intensity as a function of distinct relief exposure surfaces and to quantify these effects on the leaf area index (LAI) and other variables expressing eucalyptus forest productivity for simulations in a process-based growth model. The study was carried out at two contrasting edaphoclimatic locations in the Rio Doce basin in Minas Gerais, Brazil. Two stands with 32-year-old plantations were used, allocating fixed plots in locations with northern and southern exposure surfaces. The meteorological data were obtained from two automated weather stations located near the study sites. Solar radiation was corrected for terrain inclination and exposure surfaces, as it is measured based on the plane, perpendicularly to the vertical location. The LAI values collected in the field were used. For the comparative simulations in productivity variation, the mechanistic 3PG model was used, considering the relief exposure surfaces. It was verified that during most of the year, the southern surfaces showed lower availability of incident solar radiation, resulting in up to 66% losses, compared to the same surface considered plane, probably related to its geographical location and higher declivity. Higher values were obtained for the plantings located on the northern surface for the variables LAI, volume and mean annual wood increase, with this tendency being repeated in the 3PG model simulations.

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This paper presents the design for a graphical parameter editor for Testing and Test Control Notation 3 (TTCN-3) test suites. This work was done in the context of OpenTTCN IDE, a TTCN-3 development environment built on top of the Eclipse platform. The design presented relies on an additional parameter editing tab added to the launch configurations for test campaigns. This parameter editing tab shows the list of editable parameters and allows opening editing components for the different parameters. Each TTCN-3 primitive type will have a specific editing component providing tools to ease modification of values of that type.

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Tutkin pro gradu -tutkielmassani englannin kielen oppijoiden pragmaattista kompetenssia. Tarkoitukseni oli selvittää, miten suomalaiset yläkoululaiset ja lukiolaiset osaavat käyttää englannin kieltä erilaisissa kommunikaatiotilanteissa. Tutkielmani voidaan sijoittaa välikielen pragmatiikan tutkimukseen. Halusin selvittää, millä tasolla suomalaisten oppijoiden pragmaattinen kompetenssi on ja kehittyykö se yläkoulun ja lukion välillä. Lisäksi tutkin, vaikuttavatko oppimisympäristö ja oppimismahdollisuudet oppijoiden kykyyn käyttää englannin kieltä. Toisin sanoen vertasin englantipainotteisilla luokilla olevia oppilaita formaalin opetuksen oppijoihin sekä tutkin, vaikuttavatko englanninkieliset vapaa-ajan aktiviteetit ja oppijoiden mahdolliset oleskelut englanninkielisissä maissa heidän pragmaattiseen kompetenssiinsa. Tutkimukseni kohderyhmä koostui yläkoulun kahdeksasluokkalaisista ja lukion toisen vuosikurssin opiskelijoista. Testasin neljä eri ryhmää, joissa oli sekä formaalissa opetuksessa olevia oppijoita (yksi ryhmä kahdeksasluokkalaisia ja yksi ryhmä toisen vuosikurssin opiskelijoita) että kielipainotteisten luokkien oppijoita (yksi ryhmä kahdeksasluokkalaisia ja yksi ryhmä toisen vuosikurssin opiskelijoita). Arvioin kohderyhmäni pragmaattista kompetenssia monivalintatestillä, jossa testattiin oppijoiden kykyä käyttää ja ymmärtää implikaatioita, tilannekohtaisia rutiineja sekä puheakteja. Taustakysymysten avulla selvitin, kuinka usein oppijat käyttivät englantia vapaa-aikanaan ja olivatko he vierailleet englanninkielisissä maissa. Tutkimustulokseni osoittavat, että suomalaisten yläkoululaisten ja lukiolaisten pragmaattinen kompetenssi oli korkea. Pragmaattinen kompetenssi kehittyi kahdeksasluokkalaisten ja lukion toisen vuosikurssin välillä. Kehitys oli suurempaa formaalissa opetuksessa kuin kielipainotteisilla luokilla. Englantipainotteisilla luokilla olevat oppilaat suoriutuivat testistä paremmin kuin formaalin opetuksen oppilaat. Tosin erot olivat tilastollisesti merkitseviä vain yläkoulussa. Tutkimuksessani siis päättelin, että vieraskielinen opetus vaikutti enemmän nuorempiin oppijoihin. Eri oppimismahdollisuudet osoittautuivat haastaviksi analysoida. Tulokset osoittivat, että vain englanninkielisessä maassa oleskelulla oli vaikutusta oppijoiden pragmaattiseen kompetenssiin. Kysyttäessä vapaa-ajan aktiviteettien merkitystä oppijat kuitenkin kertoivat, että ne auttoivat heitä testiin vastaamisessa enemmän kuin englanninopetuksessa käydyt asiat. Kouluissa tulisikin jatkossa painottaa yhä enemmän vuorovaikutteista kieltenopetusta.

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This thesis studied the issue of interaction in industrial buyer-seller relationships. The aim of the thesis was to study the interaction from the seller’s perspective, especially from a project selling company’s perspective. The purpose of the thesis was to offer suggestions for the case company on how to improve interaction. The theoretical part of the study introduced the interaction framework of buyer-seller interaction, and the concept of interaction mechanisms. The focus was on studying the seller’s ways and means to utilize the interaction mechanisms. A case study research was conducted in the empirical part of the study, in which interaction in the case company was observed at a general level and through three different projects. The case company of the study was a project selling company. The case study data was gathered through individual interviews. Content Analysis was used as a research method for analyzing the case study data. Based on the case study findings, the results were drawn. The results indicated what should be done, in order to develop interaction in the case company. Finally, suggestions were provided for the case company on how to improve interaction, and a suggested interaction model was established for the case company. Although the thesis studied the topic from the viewpoint of only one specific company, it also offers outlook for other seller companies to improve their interaction.

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Parameter estimation still remains a challenge in many important applications. There is a need to develop methods that utilize achievements in modern computational systems with growing capabilities. Owing to this fact different kinds of Evolutionary Algorithms are becoming an especially perspective field of research. The main aim of this thesis is to explore theoretical aspects of a specific type of Evolutionary Algorithms class, the Differential Evolution (DE) method, and implement this algorithm as codes capable to solve a large range of problems. Matlab, a numerical computing environment provided by MathWorks inc., has been utilized for this purpose. Our implementation empirically demonstrates the benefits of a stochastic optimizers with respect to deterministic optimizers in case of stochastic and chaotic problems. Furthermore, the advanced features of Differential Evolution are discussed as well as taken into account in the Matlab realization. Test "toycase" examples are presented in order to show advantages and disadvantages caused by additional aspects involved in extensions of the basic algorithm. Another aim of this paper is to apply the DE approach to the parameter estimation problem of the system exhibiting chaotic behavior, where the well-known Lorenz system with specific set of parameter values is taken as an example. Finally, the DE approach for estimation of chaotic dynamics is compared to the Ensemble prediction and parameter estimation system (EPPES) approach which was recently proposed as a possible solution for similar problems.

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To obtain the desirable accuracy of a robot, there are two techniques available. The first option would be to make the robot match the nominal mathematic model. In other words, the manufacturing and assembling tolerances of every part would be extremely tight so that all of the various parameters would match the “design” or “nominal” values as closely as possible. This method can satisfy most of the accuracy requirements, but the cost would increase dramatically as the accuracy requirement increases. Alternatively, a more cost-effective solution is to build a manipulator with relaxed manufacturing and assembling tolerances. By modifying the mathematical model in the controller, the actual errors of the robot can be compensated. This is the essence of robot calibration. Simply put, robot calibration is the process of defining an appropriate error model and then identifying the various parameter errors that make the error model match the robot as closely as possible. This work focuses on kinematic calibration of a 10 degree-of-freedom (DOF) redundant serial-parallel hybrid robot. The robot consists of a 4-DOF serial mechanism and a 6-DOF hexapod parallel manipulator. The redundant 4-DOF serial structure is used to enlarge workspace and the 6-DOF hexapod manipulator is used to provide high load capabilities and stiffness for the whole structure. The main objective of the study is to develop a suitable calibration method to improve the accuracy of the redundant serial-parallel hybrid robot. To this end, a Denavit–Hartenberg (DH) hybrid error model and a Product-of-Exponential (POE) error model are developed for error modeling of the proposed robot. Furthermore, two kinds of global optimization methods, i.e. the differential-evolution (DE) algorithm and the Markov Chain Monte Carlo (MCMC) algorithm, are employed to identify the parameter errors of the derived error model. A measurement method based on a 3-2-1 wire-based pose estimation system is proposed and implemented in a Solidworks environment to simulate the real experimental validations. Numerical simulations and Solidworks prototype-model validations are carried out on the hybrid robot to verify the effectiveness, accuracy and robustness of the calibration algorithms.

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This study aimed to evaluate the interference of tuberculin test on the gamma-interferon (INFg) assay, to estimate the sensitivity and specificity of the INFg assay in Brazilian conditions, and to simulate multiple testing using the comparative tuberculin test and the INFg assay. Three hundred-fifty cattle from two TB-free and two TB-infected herds were submitted to the comparative tuberculin test and the INFg assay. The comparative tuberculin test was performed using avian and bovine PPD. The INFg assay was performed by the BovigamTM kit (CSL Veterinary, Australia), according to the manufacturer's specifications. Sensitivity and specificity of the INFg assay were assessed by a Bayesian latent class model. These diagnostic parameters were also estimate for multiple testing. The results of INFg assay on D0 and D3 after the comparative tuberculin test were compared by the McNemar's test and kappa statistics. Results of mean optical density from INFg assay on both days were similar. Sensitivity and specificity of the INFg assay showed results varying (95% confidence intervals) from 72 to 100% and 74 to 100% respectively. Sensitivity of parallel testing was over 97.5%, while specificity of serial testing was over 99.7%. The INFg assay proved to be a very useful diagnostic method.

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Some material aspects such as grain size, purity and anisotropy exert an important influence on surface quality, especially in single point diamond turning. The aim of this paper is to present and discuss some critical factors that can limit the accuracy of ultraprecision machining of non-ferrous metals and to identify the effects of them on the cutting mechanism with single point diamond tools. This will be carried out through observations of machined surfaces and chips produced using optical and scanning electron microscopy. Solutions to reduce the influence of some of these limiting factors related with the mechanism of generation of mirror-like surfaces will be discussed.

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The objective of this work was to optimize the parameter setup for GTAW of aluminum using an AC rectangular wave output and continuous feeding. A series of welds was carried-out in an industrial joint, with variation of the negative and positive current amplitude, the negative and positive duration time, the travel speed and the feeding speed. Another series was carried out to investigate the isolate effect of the negative duration time and travel speed. Bead geometry aspects were assessed, such as reinforcement, penetration, incomplete fusion and joint wall bridging. The results showed that currents at both polarities are remarkably more significant than the respective duration times. It was also shown that there is a straight relationship between welding speed and feeding speed and this relationship must be followed for obtaining sound beads. A very short positive duration time is enough for arc stability achievement and when the negative duration time is longer than 5 ms its effect on geometry appears. The possibility of optimizing the parameter selection, despite the high inter-correlation amongst them, was demonstrate through a computer program. An approach to reduce the number of variables in this process is also presented.

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The nonlinear interaction between Görtler vortices (GV) and three-dimensional Tollmien-Schlichting (TS) waves nonlinear interaction is studied with a spatial, nonparallel model based on the Parabolized Stability Equations (PSE). In this investigation the effect of TS wave frequency on the nonlinear interaction is studied. As verified in previous investigations using the same numerical model, the relative amplitudes and growth rates are the dominant parameters in GV/TS wave interaction. In this sense, the wave frequency influence is important in defining the streamwise distance traveled by the disturbances in the unstable region of the stability diagram and in defining the amplification rates that they go through.

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Modelling of the slug structure requires a new effort on fundamental research. To clarify some aspects of the horizontal slug flow, an experimental study of the behaviour of two isolated bubbles in a single-phase liquid flow was performed. This procedure was adopted to avoid the overlap of different phenomena induced by a train of long bubbles. The experimental facility consists of a 90-m horizontal PVC pipe with internal diameter of 0,053 m. The behaviour of two single air bubbles travelling in a water flow was studied. Focus was given on the influence of the distance between the bubbles on the velocity of the second bubble. This study allows the understanding of the mechanism of overtaking that takes place right after the slug formation and that precedes the coalescence of bubbles in a slug flow. The results show that bubbles placed behind a liquid slug smaller than a critical value move faster than the leading one. Otherwise, they move slower than the leading one.