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11.
The problem of constructing functional observers for linear systems with unknown inputs is considered. Necessary and sufficient conditions for the existence of a proper observer (without differentiations) are revisited. A simple and explicit form of a functional observer is presented. It is shown that when such observer is not proper, it is still possible to use the High-Order Sliding Mode differentiator to implement it. Nevertheless, in such case, additional conditions on the system and the unknown input are required.  相似文献   
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The objective of this study was to assess the relationship between the institutionalization of a dependent elderly relative and the family caregiver’s mental health, quality of life and caregiving satisfaction. We present data from 140 family caregivers caring for elderly family members, of whom 77 continued to live with family members and 63 had been institutionalized. We evaluated the factors influencing the decision to institutionalize the dependent relative, the effect of institutionalization on the caregiver’s psychological well-being and quality of life and the impact of strategies to find the meaning and cope with the relative’s placement on the caregiver’s emotional health and quality of life. Care does not end after institutionalization, but the stressors the caregiver faces change. Our results suggest that finding meaning increases satisfaction and reduces feelings of overload. They show that after institutionalization, stressors affecting caregivers are partly relieved, and that finding meaning increases the caregiver’s satisfaction, while decreasing the degree of overload. Our data, further, indicates that a good relationship and cooperation between the staff of the institution and the family are important to improve the caregivers’ emotional health and quality of life, and consequently, the quality of life of the dependent elderly relative.  相似文献   
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The aim of this research has been to test the efficacy of an intervention programme on lexical-semantic problems in children with Specific Language Impairment (SLI). The sample consisted of 34 children diagnosed with SLI and 34 children with typical language development, all enrolled in different schools on the island of Tenerife (Canary Islands, Spain). For the selection of the sample, CELF-3, Peabody, ITPA Auditory Association and Visual Association subtests and the K-BIT IQ tests were used. The intervention programme consisted of 72 sessions of 30 minutes each, using noun and action naming activities along with conversation and categorization tasks in order to increase vocabulary and improve lexical semantic competence. Significant results were achieved in aspects related to the acquisition of vocabulary as well as in lexical semantics or related terms. The educational implications are clear insofar as lexical-semantic aspects are key in terms of activating other linguistic components and in improving the academic progress of SLI students.  相似文献   
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The Atlas of Erotic Anatomy and Arousal is online video education that explores sexual pleasure and sexual anatomy from a sex positive perspective. Written and presented by a sex educator and therapist, Cyndi Darnell, this video is an excellent resource for adult individuals interested in learning about their bodies and having fulfilling sexual experiences with their partners. The video series provides scientifically accurate and pleasure-based information about the anatomy of the vulva, the penis, and the anus, and the physiology of orgasm and ejaculation, in an entertaining manner.  相似文献   
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This study documents the reliability and validity of a new infant-toddler authentic assessment, the Learning Through Relating Child Assets Record (LTR-CAR), and its feasibility of use by infant-toddler caregivers in an Early Head Start program. In a sample of 136 children, results indicated a strong internal structure of the LTR-CAR as evidenced by high internal consistency within age bands, expected performance in terms of the order of difficulty of items, and expected performance relative to the chronological ages of children. Moreover, the LTR-CAR accounted for a statistically significant amount of unique variance (between 6 and 26%), over and above age and gender, in six out of eight regressions predicting criterion measures. Given the increasing numbers of infants and toddlers in non-parental care, the need for authentic assessment as a tool to plan meaningful learning opportunities, as well as the lack of evidence-based authentic assessment options at the infant-toddler level, the LTR-CAR may provide a viable option for the field.  相似文献   
17.
The journal impact factor (JIF) is the average of the number of citations of the papers published in a journal, calculated according to a specific formula; it is extensively used for the evaluation of research and researchers. The method assumes that all papers in a journal have the same scientific merit, which is measured by the JIF of the publishing journal. This implies that the number of citations measures scientific merits but the JIF does not evaluate each individual paper by its own number of citations. Therefore, in the comparative evaluation of two papers, the use of the JIF implies a risk of failure, which occurs when a paper in the journal with the lower JIF is compared to another with fewer citations in the journal with the higher JIF. To quantify this risk of failure, this study calculates the failure probabilities, taking advantage of the lognormal distribution of citations. In two journals whose JIFs are ten-fold different, the failure probability is low. However, in most cases when two papers are compared, the JIFs of the journals are not so different. Then, the failure probability can be close to 0.5, which is equivalent to evaluating by coin flipping.  相似文献   
18.
In distributed and cooperative systems, the network structure is determinant to the success of the strategy adopted to solve complex tasks. Those systems are primarily governed by consensus protocols whose convergence is intrinsically dependent on the network topology. Most of the consensus algorithms deal with continuous values and perform average-based strategies to reach cohesion over the exchanged information. However, many problems demand distributed consensus over countable values, that cannot be handled by traditional protocols. In such a context, this work presents an approach based on semidefinite programming to design the optimal weights of a network adjacency matrix, in order to control the convergence of a distributed random consensus protocol for variables at the discrete-space domain, based on the voter model. As a second contribution, this work uses Markov theory and the biological inspiration of epidemics to find out a dynamical spreading model that can predict the information diffusion over this discrete consensus protocol. Also, convergence properties and equilibrium points of the proposed model are presented regarding the network topology. Finally, extensive numerical simulations evaluate the effectiveness of the proposed consensus algorithm, its spreading model, and the approach for optimal weight design.  相似文献   
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Abstract High physical fitness in childhood and adolescence is positively associated with favourable health-related outcomes. Our aim was to examine the relationship between relatives' (father, mother, brother, sister, and best friend) physical activity engagement and encouragement on adolescents' physical fitness. Adolescents were part of the HELENA study, a multi-centre study conducted in 10 cities from nine European countries in 2006-2008. Participants were 3288 adolescents (48% boys, 52% girls) aged 12.5-17.5 years with valid data on at least one of the three fitness variables studied: muscular strength (standing long jump), speed/agility (4×10 m shuttle run), and cardiorespiratory fitness (20 m shuttle run). The adolescents reported their relatives' physical activity engagement and encouragement. Analysis of covariance showed that relatives' physical activity engagement (father, mother, brother, and best friend) was positively related to cardiorespiratory fitness (P?相似文献   
20.
As a mixture of new technologies, processes and services oriented to the citizen, e-government has become one of the most important keywords for the public sector reform with proponents claiming that it guarantees transparency, accountability and better communication between local and national administrations and their public. Few if any studies have investigated the factors that might contribute to the establishment of trusting relationship between city councils and citizens. This paper examines the relative importance and significance of three types of information communication technologies (ICTs) towards the use of e-government and the development of civic engagement. We conduct an empirical investigation of 179 Spanish official town websites (web sites in the municipalities). The research findings suggest that implementing ICT not only involves a step towards an increase in the use of e-government services by people, but also provides numerous opportunities for their civic engagement. The main conclusion of this study is that although ICT can leverage the adoption of e-government, it cannot create alone engagement with traditional activities of the local government. What is missing from this relationship is a mediating variable (adoption of e-government by government officers), which in turn can greatly help to better understand how ICT impacts relationships between governments and their citizens.  相似文献   
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