958 resultados para static structure factor
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Tutkimuksen tavoitteena on identifioida yleisimmät toimintolaskennan implementointiin liittyvät ongelmat ja muutosprojektin onnistumiseen vaikuttavat tekijät. Tavoitteena on myös saada kokonaisvaltainen kuva siitä, miksi laskentatoimen muutokset ovat vaikeita implementoida ja miten ihmisten käyttäytyminen vaikuttaa muutosprosessin onnistumiseen. Sekä laskentatoimen että muutosjohtamisen teorioita tarkastellaan laaja-alaisen kuvan saamiseksi siitä, miten ihmisiin ja heidän käyttäytymiseensä liittyvät tekijät vaikuttavat muutosprojektin onnistumiseen tai epäonnistumiseen. Tutkielma käyttää empiirisiä tutkimustuloksia pohjana aiheen tarkastelulle. Tutkielma tarjoaa ehdotuksia tulevaisuuden tutkimukselle liittyen laskentatoimen muutoksen kriittisiin tekijöihin. Kiinnostavimpia alueita tulevaisuuden tutkimukselle on pohtia tarkemmin, miten työntekijöiden oletukset johtajien motiiveista muutoksen takana vaikuttavat muutosvastarintaan sekä miten organisaation rakenne ja muutosvastarintavaikuttavat muutoksen institutionaalistamiseen.
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One of the goals of psychological assessment focuses on the adaptation of its instruments to different populations. The objective of this study is to establish the psychometric properties and dimensional structure of the Spanish version of the Coping Responses Inventory- Adult Form (CRI-Adult, Moos, 1993). The following criteria were analyzed: a) descriptive statistics; b) internal consistency reliability (Cronbach"s alpha, and intercorrelations between scales); c) test-retest reliability (4-week interval); d) dimensionality of CRI-Adult (exploratory factor analysis); e) construct validity (confirmatory factor analysis); f) convergent criterion validity (correlations between CRI-Adult and Coping Strategies Indicator, CSI, Amirkhan, 1990), and g) predictive criterion validity (correlations between CRI-Adult, and SCL-90-R, Derogatis, 1983). The results, obtained with 800 adults from Barcelona and surrounding area (334 men and 466 women, aged between 18 to 76 years) indicate that the Spanish version of CRIAdult has satisfactory psychometric properties that allow using this test with guarantee.
Identification-commitment inventory (ICI-Model): confirmatory factor analysis and construct validity
Resumo:
The aim of this study is to confirm the factorial structure of the Identification-Commitment Inventory (ICI) developed within the frame of the Human System Audit (HSA) (Quijano et al. in Revist Psicol Soc Apl 10(2):27-61, 2000; Pap Psicól Revist Col Of Psicó 29:92-106, 2008). Commitment and identification are understood by the HSA at an individual level as part of the quality of human processes and resources in an organization; and therefore as antecedents of important organizational outcomes, such as personnel turnover intentions, organizational citizenship behavior, etc. (Meyer et al. in J Org Behav 27:665-683, 2006). The theoretical integrative model which underlies ICI Quijano et al. (2000) was tested in a sample (N = 625) of workers in a Spanish public hospital. Confirmatory factor analysis through structural equation modeling was performed. Elliptical least square solution was chosen as estimator procedure on account of non-normal distribution of the variables. The results confirm the goodness of fit of an integrative model, which underlies the relation between Commitment and Identification, although each one is operatively different.
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Helicobacter pylori is an important human pathogen associated with serious gastric diseases. Owing to its medical importance and close relationship with its human host, understanding genomic patterns of global and local adaptation in H. pylori may be of particular significance for both clinical and evolutionary studies. Here we present the first such whole genome analysis of 60 globally distributed strains, from which we inferred worldwide population structure and demographic history and shed light on interesting global and local events of positive selection, with particular emphasis on the evolution of San-associated lineages. Our results indicate a more ancient origin for the association of humans and H. pylori than previously thought. We identify several important perspectives for future clinical research on candidate selected regions that include both previously characterized genes (e.g., transcription elongation factor NusA and tumor necrosis factor alpha-inducing protein Tipα) and hitherto unknown functional genes.
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The Brief Symptom Inventory is designed to assess symptoms of psychological disorders in adolescents and adults. The dimensional structure of the inventory, using exploratory and confirmatory factor analyses, was examined with a cross-sectional design in a Spanish sample of college students (N = 1,033, aged between 18 and 30 years old). Two hypotheses were tested: the original distribution of the items in nine factors, and the unidimensionality of the inventory. According to the results, a nine-factor structure seemed to be confirmed, although the strong intercorrelations found among the subscales indicated that these were measuring closely related constructs. The importance of cultural influences when assessing psychological symptoms and the need to develop national and sex norms for instruments that assess psychopathology, are also discussed.
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Tämän diplomityön tarkoituksena on löytää halvin tapa kohdeyrityksen tuotteiden saamiseksi määritellyille kohdemarkkinoille. Logistiset kustannukset ovat erityisen tärkeässä asemassa esimerkkitoimialalla, ja käytettävissä olevien logististen ratkaisujen kirjo tekee tehtävästä erityisen haastavan. Yrityksen ja teollisuudenalan erityispiirteiden esittelyn jälkeen valitaan sopiva tapa päästä markkinoille, minkä lisäksi pohditaan erilaisia kilpailustrategioita yrityksen aikaisempien kokemusten ja teoreettisen käsittelyn pohjalta. Tämä pohdinta on erilaisten analyysimenetelmien esittelyn lisäksi työn empiirisen osan taustalla. Logistiikkaympäristön ymmärtäminen ja sen tarjoamien mahdollisuuksien tunnistaminen ovat tärkeimmällä sijalla koko tutkimuksen ajan. Työssä tarkastellaan myös vientilogistiikan ja kohdemarkkinoiden erityispiirteitä, joita sovelletaan harkitsemisenarvoisiin kuljetustapoihin. Mahdollisten logististen ratkaisujen kustannusrakenteen ja kilpailukyvyn selvittämiseksi päätöksenteon tueksi luodaan yksilölliset vuokaaviot yrityksen omien kokemusten ja eri logistiikkapalvelujen tarjoajien lausuntojen perusteella. Näin voidaan edelleen tunnistaa mielekkäimmät logistiset ketjut ja arvioida niiden kustannustehokkuutta sekä suorien logististen että laatukustannusten suhteen. Lisäksi esimerkkien avulla tarkastellaan mahdollisuuksia benchmarkkaukseen. Työn lopuksi suositellaan johtopäätösten pohjalta tulevia toimenpiteitä, jotta myös jatkossa saataisiin aikaan vastaavaa pohdintaa ja toimintaa.
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Laser diffraction (LD) and static image analysis (SIA) of rectangular particles [United States Pharmacopeia, USP30-NF25, General Chapter <776>, Optical Miroscopy.] have been systematically studied. To rule out sample dispersion and particle orientation as the root cause of differences in size distribution profiles, we immobilize powder samples on a glass plate by means of a dry disperser. For a defined region of the glass plate, we measure the diffraction pattern as induced by the dispersed particles, and the 2D dimensions of the individual particles using LD and optical microscopy, respectively. We demonstrate a correlation between LD and SIA, with the scattering intensity of the individual particles as the dominant factor. In theory, the scattering intensity is related to the square of the projected area of both spherical and rectangular particles. In traditional LD the size distribution profile is dominated by the maximum projected area of the particles (A). The diffraction diameters of a rectangular particle with length L and breadth B as measured by the LD instrument approximately correspond to spheres of diameter ØL and ØB respectively. Differences in the scattering intensity between spherical and rectangular particles suggest that the contribution made to the overall LD volume probability distribution by each rectangular particle is proportional to A2/L and A2/B. Accordingly, for rectangular particles the scattering intensity weighted diffraction diameter (SIWDD) explains an overestimation of their shortest dimension and an underestimation of their longest dimension. This study analyzes various samples of particles whose length ranges from approximately 10 to 1000 μm. The correlation we demonstrate between LD and SIA can be used to improve validation of LD methods based on SIA data for a variety of pharmaceutical powders all with a different rectangular particle size and shape.
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This paper focuses on the study of the factorial structure of an inventory to estimate the subjective perception of insecurity and fear of crime. Made from the review of the literature on the subject and the results obtained in previous works, this factor structure shows that this attitude towards insecurity and fear of crime is identified through a number of latent factors which are schematically summarized in (a) personal safety, (b) the perception of personal and social control, (c) the presence of threatening people or situations, (d) the processes of identity and space appropriation, (e) satisfaction with the environment, and (f) the environmental and the use of space. Such factors are relevant dimensions to analyze the phenomenon. Method: A sample of 571 participants in a neighborhood of Barcelona was evaluated with the proposed inventory, which yielded data from the distributions of all the items provided. The administration was conducted by researchers specially trained for it and the results were analyzed by using standard procedures in the confirmatory factor analysis (CFA) from the hypothesized theoretical structure. The analysis was performed by decatypes according to the different response scales prepared in the inventory and their ordinal nature, and by estimating the polychoric correlation coefficients. The results show an acceptable fit of the proposed model, an appropriate behavior of the residuals and statistically significant estimates of the factor loadings. This would indicate the goodness of the proposed factor structure.
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Electron scattering on unstable nuclei is planned in future facilities of the GSI and RIKEN upgrades. Motivated by this fact, we study theoretical predictions for elastic electron scattering in the N=82, N=50, and N=14 isotonic chains from very proton-deficient to very proton-rich isotones. We compute the scattering observables by performing Dirac partial-wave calculations. The charge density of the nucleus is obtained with a covariant nuclear mean-field model that accounts for the low-energy electromagnetic structure of the nucleon. For the discussion of the dependence of scattering observables at low-momentum transfer on the gross properties of the charge density, we fit Helm model distributions to the self-consistent mean-field densities. We find that the changes shown by the electric charge form factor along each isotonic chain are strongly correlated with the underlying proton shell structure of the isotones. We conclude that elastic electron scattering experiments on isotones can provide valuable information about the filling order and occupation of the single-particle levels of protons.
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BackgroundBipolar disorder is a highly heritable polygenic disorder. Recent enrichment analyses suggest that there may be true risk variants for bipolar disorder in the expression quantitative trait loci (eQTL) in the brain.AimsWe sought to assess the impact of eQTL variants on bipolar disorder risk by combining data from both bipolar disorder genome-wide association studies (GWAS) and brain eQTL.MethodTo detect single nucleotide polymorphisms (SNPs) that influence expression levels of genes associated with bipolar disorder, we jointly analysed data from a bipolar disorder GWAS (7481 cases and 9250 controls) and a genome-wide brain (cortical) eQTL (193 healthy controls) using a Bayesian statistical method, with independent follow-up replications. The identified risk SNP was then further tested for association with hippocampal volume (n = 5775) and cognitive performance (n = 342) among healthy individuals.ResultsIntegrative analysis revealed a significant association between a brain eQTL rs6088662 on chromosome 20q11.22 and bipolar disorder (log Bayes factor = 5.48; bipolar disorder P = 5.85×10(-5)). Follow-up studies across multiple independent samples confirmed the association of the risk SNP (rs6088662) with gene expression and bipolar disorder susceptibility (P = 3.54×10(-8)). Further exploratory analysis revealed that rs6088662 is also associated with hippocampal volume and cognitive performance in healthy individuals.ConclusionsOur findings suggest that 20q11.22 is likely a risk region for bipolar disorder; they also highlight the informative value of integrating functional annotation of genetic variants for gene expression in advancing our understanding of the biological basis underlying complex disorders, such as bipolar disorder.
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On this instrumental study we intend to analyse the factorial structure of the Screen for Child Anxiety Related Emotional Disorders (SCARED) in a Spanish sample using exploratory and confirmatory factorial analysis. As a second objective we intend to develop a short form of it for rapid screening and, finally, to analyze the reliabilities of both questionnaires. The SCARED was administered to a community sample of 1,508 children aged between 8 and 12 years. The sample was randomly split using half for the exploratory analysis and the other half for the confirmatory study. Furthermore a reduced version of the SCARED was developed using the SchmidLeiman procedure. Exploratory Factor Analysis yielded a four factor structure comprised of Somatic/panic, Generalized anxiety, Separation anxiety and Social phobia factors This structure was confirmed using Confirmatory Factor Analysis. The four factors, the full scale and the short scale showed good reliabilities. The results obtained seem to indicate that the Spanish version of the SCARED has good internal consistency, and along with other recent results, has a structure of four related factors that replicates the dimensions proposed for anxiety disorders by the DSM-IV-TR
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For any international companies who wish to enter the Chinese market, quality is base on the fundamental. The companies are coming to realize the importance of quality gradually, thus companies have been put the quality problems on the agenda. The competitiveness of companies comes from quality. Quality is the key to success, and it can decide that the companies can be accepted or eliminated by the market. Due to the obvious benefits, the demand of the method of how to achieve high quality of product keeps growing. During achieving the high quality process, the main troubles come from the impact between Eastern and Western culture. Chinese culture which is different with Western one have lasted as long as five thousand years. Such a culture deeply rooted in the hearts of Chinese people, and effected generation after generation of Chinese people's working style and ways of thinking. This thesis determines how to find a good fit point between Eastern and Western culture. Doing right thing by the right way. The nature of improving quality is improving management level in fact. "How to manage, who should be managed", the thesis explains the basic and best option to achieve those. It describes three-dimension-style management to monitoring the working process. This kind of management style can inspect production process from horizontal and vertical direction. In this management way, it defines effective evaluation system to every subcontractor, and makes the companies to achieve the ultimate goal - satisfy quality. Because of the importance of human factor, the thesis determines the range of training of the inspector and welder due to the current situation of China. The results show that in order to reach reliable training effective evaluation, not only the quality of the human but also the ultimate goal of product quality.
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Edge effects are considered a key factor in regulating the structure of plant communities in different ecosystems. However, regardless to few studies, edge influence does not seem to be decisive in semiarid regions such as the Brazilian tropical dry forest known as Caatinga but this issue remains inconclusive. The present study tests the null hypothesis that the plant community of shrubs and trees does not change in its structure due to edge effects. Twenty-four plots (20 x 20 m) were set up in a fragment of Caatinga, in which 12 plots were in the forest edges and 12 plots were inside the fragment. Tree richness, abundance and species composition did not differ between edge and interior plots. The results of this study are in agreement with the pattern previously found for semiarid environments and contrasts with previous results obtained in different environments such as Rainforests, Savanna and Forest of Araucaria, which indicate abrupt differences between the border and interior of the plant communities in these ecosystems, and suggest that the community of woody plants of the Caatinga is not ecologically affected by the presence of edges.
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Transport properties of GaAs / δ – Mn / GaAs / InxGa1-xAs / GaAs structure with Mn δ – layer, which is separated from InxGa1-xAs quantum well (QW) by 3 nm thick GaAs spacer was investigated. This structure with high mobility was characterized by X-ray difractometry and reflectometry. Transport and electrical properties of the structure were measured by using Pulsed Magnetic Field System (PMFS). During investigation of the Shubnikov – de Haas and the Hall effects the main parameters of QW structure such as cyclotron mass, Fermi level, g – factor, Dingle temperature and concentration of holes were estimated. Obtained results show high quality of the prepared structure. However, anomalous Hall effect at temperatures 2.09 K, 3 K, 4.2 K is not clearly observed. Attempts to identify magnetic moment were made. For this purpose the polarity of the filed was changed to the opposite at each shot. As a result hysteresis loop was not observed in the magnetic field dependences of the anomalous Hall resistivity.This can be attributed to the imperfection of the experimental setup.
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Control of an industrial robot is mainly a problem of dynamics. It includes non-linearities, uncertainties and external perturbations that should be considered in the design of control laws. In this work, two control strategies based on variable structure controllers (VSC) and a PD control algorithm are compared in relation to the tracking errors considering friction. The controller's performances are evaluated by adding an static friction model. Simulations and experimental results show it is possible to diminish tracking errors by using a model based friction compensation scheme. A SCARA robot is used to illustrate the conclusions of this paper.