University of Huelva

About: University of Huelva is a education organization based out in Huelva, Spain. It is known for research contribution in the topics: Population & Acid mine drainage. The organization has 3176 authors who have published 7698 publications receiving 142516 citations. The organization is also known as: Universidad de Huelva.

Understanding e-learning continuance intention: An extension of the Technology Acceptance Model

Abstract: Based on the expectancy disconfirmation theory, this study proposes a decomposed technology acceptance model in the context of an e-learning service. In the proposed model, the perceived performance component is decomposed into perceived quality and perceived usability. A sample of 172 respondents took part in this study. The results suggest that users' continuance intention is determined by satisfaction, which in turn is jointly determined by perceived usefulness, information quality, confirmation, service quality, system quality, perceived ease of use and cognitive absorption.

A New Supervised Method for Blood Vessel Segmentation in Retinal Images by Using Gray-Level and Moment Invariants-Based Features

Abstract: This paper presents a new supervised method for blood vessel detection in digital retinal images. This method uses a neural network (NN) scheme for pixel classification and computes a 7-D vector composed of gray-level and moment invariants-based features for pixel representation. The method was evaluated on the publicly available DRIVE and STARE databases, widely used for this purpose, since they contain retinal images where the vascular structure has been precisely marked by experts. Method performance on both sets of test images is better than other existing solutions in literature. The method proves especially accurate for vessel detection in STARE images. Its application to this database (even when the NN was trained on the DRIVE database) outperforms all analyzed segmentation approaches. Its effectiveness and robustness with different image conditions, together with its simplicity and fast implementation, make this blood vessel segmentation proposal suitable for retinal image computer analyses such as automated screening for early diabetic retinopathy detection.

Fluorescent dyes and their supramolecular host/guest complexes with macrocycles in aqueous solution.

Abstract: Fluorescent Dyes and Their Supramolecular Host/Guest Complexes with Macrocycles in Aqueous Solution Roy N. Dsouza, Uwe Pischel,* and Werner M. Nau* School of Engineering and Science, Jacobs University Bremen, Campus Ring 1, D-28759 Bremen, Germany Centro de Investigaci on en Química Sostenible (CIQSO) and Departamento de Ingeniería Química, Química Física y Química Org anica, Universidad de Huelva, Campus de El Carmen s/n, E-21071 Huelva, Spain

Coinage metal catalyzed C-H bond functionalization of hydrocarbons.

Abstract: 3.1. The Reaction 3381 3.2. The Catalysts and the Carbene Source 3381 3.3. Achievements 3383 3.4. Selectivity and Mechanistic Considerations 3386 3.5. Future Development 3386 4. C-H Bond Functionalization by Nitrene Insertion 3387 4.1. The Reaction 3387 4.2. The Catalysts and the Nitrene Sources 3387 4.3. Development and Mechanistic Considerations 3388 4.4. Future Development 3389 5. C-H Bond Oxidations 3389 5.1. The Reaction and the Catalysts 3389 5.2. Development and Perspective 3390 6. Conclusions 3393 7. Acknowledgments 3393 8. References 3393