Periodic solutions of integro-differential equations in vector-valued function spaces

AbstractOperator-valued Fourier multipliers are used to study well-posedness of integro-differential equations in Banach spaces. Both strong and mild periodic solutions are considered. Strong well-posedness corresponds to maximal regularity which has proved very efficient in the handling of nonlinear problems. We are concerned with a large array of vector-valued function spaces: Lebesgue–Bochner spaces Lp, the Besov spaces Bp,qs (and related spaces such as the Hölder–Zygmund spaces Cs) and the Triebel–Lizorkin spaces Fp,qs. We note that the multiplier results in these last two scales of spaces involve only boundedness conditions on the resolvents and are therefore applicable to arbitrary Banach spaces. The results are applied to various classes of nonlinear integral and integro-differential equations

Expectation vs. Reality in the Field of Entrepreneurship

Cognitive elements are some of the most influential features characterizing the “entrepreneurial mind,” yet dominant explanatory frameworks have struggled to clarify how and why entrepreneurs’ behaviors vary so widely from others. Even individuals who come from similar conditions and share the same environment as entrepreneurs differ greatly in their perceptions and behaviors compared to their entrepreneur counterparts. Drawing on and contributing to the theoretical work in social cognitive theory, this research aims to improve the understanding of entrepreneurs’ cognitive processes by exploring Global Entrepreneurship Monitor data, which is the most comprehensive comparative database for entrepreneurship. The first essay analyzes how different experts in entrepreneurship perceive their surrounding environment and opportunities. More specifically, this study discusses how experts who are entrepreneurs perceive their entrepreneurial ecosystem and opportunities differently than non-entrepreneur experts. It is suggested that people act the way they do not only because of different interpretations of the environment but also because of the relative importance they give to context and themselves in their mental frameworks. The second essay analyzes the relationship between optimism about the emergence of future entrepreneurial opportunities and the length of entrepreneurial experience and the ways internal and external motivations can condition this relationship. Results suggest that although entrepreneurs are more optimistic about future business opportunities that non-entrepreneurs, experienced entrepreneurs tend to be less optimistic than novice and potential entrepreneurs. Finally, based on evidence suggesting that entrepreneurs are likely to consider that fostering an innovative orientation is the best approach to increasing firm performance independent of the circumstances, the third study proposes a moderated mediation model of the effect of subjective valuations of innovation on entrepreneurs’ strategic orientation and growth expectations. Entrepreneurs involved in innovative entrepreneurship are more likely to have higher growth expectation, with subjective valuations playing a direct and indirect role in their expectations

How do motivational factors influence entrepreneurs’ perception of business opportunities in different stages of entrepreneurship?

The purpose of this paper is twofold: first, it analyses the relationship between optimism about the emergence of future entrepreneurial opportunities and the length of the entrepreneurial experience; second, it aims to identify the external factors that can moderate this relationship. Our empirical analysis is conducted on a cross-national sample of 450,000 individuals drawn from the Adult Population Survey (APS), which is collected by the Global Entrepreneurship Monitor (GEM) consortium and covers the period from 2009 to 2011. Our results find an inverted U-shaped relationship between the length of the entrepreneurial experience and our indicator of optimism. Additionally, the relationship between optimism and length of entrepreneurial experience is conditioned by a set of external-factor moderators, such as social capital and the individuals’ perception of how valued entrepreneurship is as a career choice in their country

El objeto del Derecho del Trabajo y su extensión

Al decir del tratadista español MANUEL ALONSO GARCÍA debeentenderse por objeto una disciplina científica, la parte de la realidadsocial susceptible de estudio independiente y de la cual se ocupadicha disciplina.Así, en el caso del Derecho del Trabajo/ tal objeto está integradopor el trabajo humano que presenta determinadas características y esejecutado en determinadas condiciones; generándose, de esta manera/una suerte de concepto jurídico-laboral de trabajo.Puede en esta forma, caracterizarse el trabajo integrante del objetodel Derecho del Trabajo clásico o tradicional, nacional e internacional,como aquel que proviene del hombre y que es ejecutado en formavoluntaria, libre, productiva/ por cuenta ajena, subordinada o dependiente,personal y continuada o permanent

Formación inicial docente en música en tres universidades chilenas: evolución y cambio curricular, 1981 - 2008.

El presente artículo describe la evolución de los currícula de formación inicial docente en música (FID – M), en tres universidades chilenas entre 1981 y 2009. A partir del análisis de fuentes documentales –planes de estudio implementados en cada institución a lo largo del período preestablecido - se buscará identificar las formas en que los distintos tipos de conocimiento participan de la organización de los currícula, así como de las relaciones existentes entre tipos de conocimiento, al interior de cada propuesta. El análisis se realizará mediante la aplicación de un modelo de categorización que reconoce cuatro ámbitos distintivos del conocimiento profesional docente, identificando fluctuaciones sobre la distribución de dichos tipos de conocimiento en las propuestas curriculares implementadas en el período. Los resultados buscan objetivar la evolución curricular de la FID - M al interior de cada institución, integrando historia institucional, políticas curriculares y contextos socio históricos

Detection and segmentation of vine canopy in ultra-high spatial resolution RGB imagery obtained from unmanned aerial vehicle (UAV): a case study in a commercial vineyard

The use of Unmanned Aerial Vehicles (UAVs) in viticulture permits the capture of aerial Red-Green-Blue (RGB) images with an ultra-high spatial resolution. Recent studies have demonstrated that RGB images can be used to monitor spatial variability of vine biophysical parameters. However, for estimating these parameters, accurate and automated segmentation methods are required to extract relevant information from RGB images. Manual segmentation of aerial images is a laborious and time-consuming process. Traditional classification methods have shown satisfactory results in the segmentation of RGB images for diverse applications and surfaces, however, in the case of commercial vineyards, it is necessary to consider some particularities inherent to canopy size in the vertical trellis systems (VSP) such as shadow effect and different soil conditions in inter-rows (mixed information of soil and weeds). Therefore, the objective of this study was to compare the performance of four classification methods (K-means, Artificial Neural Networks (ANN), Random Forest (RForest) and Spectral Indices (SI)) to detect canopy in a vineyard trained on VSP. Six flights were carried out from post-flowering to harvest in a commercial vineyard cv. Carménère using a low-cost UAV equipped with a conventional RGB camera. The results show that the ANN and the simple SI method complemented with the Otsu method for thresholding presented the best performance for the detection of the vine canopy with high overall accuracy values for all study days. Spectral indices presented the best performance in the detection of Plant class (Vine canopy) with an overall accuracy of around 0.99. However, considering the performance pixel by pixel, the Spectral indices are not able to discriminate between Soil and Shadow class. The best performance in the classification of three classes (Plant, Soil, and Shadow) of vineyard RGB images, was obtained when the SI values were used as input data in trained methods (ANN and RForest), reaching overall accuracy values around 0.98 with high sensitivity values for the three classes

USCID fourth international conference

Presented at the Role of irrigation and drainage in a sustainable future: USCID fourth international conference on irrigation and drainage on October 3-6, 2007 in Sacramento, California.Includes bibliographical references.The two-layer model of Shuttlerworth and Wallace (SW) was evaluated to estimate actual evapotranspiration (ETa) above a drip-irrigated Merlot vineyard, located in the Talca Valley, Region del Maule, Chile (35° 25' LS; 71° 32' LW ; 136m above the sea level). An automatic weather system was installed in the center of the vineyard to measure climatic variables (air temperature, relative humidity, and wind speed) and energy balance components (solar radiation, net radiation, latent heat flux, sensible heat flux, and soil heat flux) during November and December 2006. Values of ETa estimated by the SW model were tested with latent heat flux measurements obtained from an eddy-covariance system on a 30 minute time interval. Results indicated that SW model was able to predict ETa with a root mean square error (RMSE) of 0.44 mm d-1 and mean absolute error (MAE) of 0.36 mm d-1. Furthermore, SW model predicted latent heat flux with RMSE and MAE of 32 W m-2 and 19W m-1, respectively

Guiding safer risperidone prescribing in Alzheimer's disease with therapeutic drug monitoring

Previous analysis of pharmacokinetic data on risperidone-treated patients with dementia predicted that 20% had concentration-to-dose (C/D) ratios of the active moiety (risperidone and 9-hydroxy(OH)-risperidone) above 14 ng/mL per mg/day, which were in turn associated with a greater risk of extrapyramidal side effects. This study aimed to further explore risperidone pharmacokinetics in a second dataset. Nonlinear mixed effects modelling, using a Bayesian approach, was applied to data from a randomized controlled trial of risperidone in people with dementia. Covariates included age and glomerular filtration rate (GFR). Age had a significant effect on risperidone clearance (β = −1.5) and GFR on 9-OH-risperidone clearance (β = 0.2). The model predicted that 26.2% (95% confidence interval 18.6-32.6%) had C/D ratios above 14 ng/mL per mg/day. These findings confirm the importance of age-related risperidone dose adjustments and argue strongly for therapeutic drug monitoring in the initial stages of treatment to identify those at greatest risk of toxicity