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1.
New cellulosic titanium dioxide nanocomposite as a protective coating for preserving paper-art-works
We investigate the TiO2 role in the inherent protection of paper works of art to protect them against damaging effect of ultraviolet radiation, pollutant gasses, mold and bacteria. In this study a cellulosic nanocomposite of TiO2 were used as protective coating on the surface of paper fibers. This layered nanocomposite can act as a consolidate materials too. Furthermore, to determine how well paper works screen objects from the damaging effects, two accelerated aging mechanisms due to light and heat are discussed. Results show good stability of papers with nanocomposite coating. Also, a good light stability was shown in the colored paper that treated with this nanocomposite. Furthermore, to demonstrate the degree of antifungal properties of coated papers, papers were treated with two common molds and the good preventive effect of coated paper against molds is described. 相似文献
2.
OBJECTIVE: This study examines the relationship between parental self-confidence, warmth, and involvement, and corporal punishment in families of children with attention deficit/hyperactivity disorder (ADHD). METHOD: The diagnosis of ADHD was established through clinical interviews with the parents, children, and teachers, according the criteria in DSM-IV-TR. This diagnosis was also established by having the parents complete the Conners' Parent Rating Scale, and the teachers complete the Conners' Teacher Rating Scale. Two groups of Iranian parents, one group with children who have ADHD (N=130) and a control group (N=120), completed questionnaires measuring parental self-confidence and parenting styles. RESULTS: Parents of children with ADHD were found to have lower self-confidence and less warmth and involvement with their children, and used corporal punishment significantly more than the parents of control children. CONCLUSIONS: The study provides strong evidence that children with ADHD are at considerable risk of abuse by their parents. Rather than focusing only on the child's ADHD, treatment may also need to address the parents' functioning. 相似文献
3.
Several studies have found that older women report lower self-rated health than men. However, it is not clear why older women are more likely to report poor self-rated health than older men. Data for this study came from a national cross-sectional survey, Mental Health and Quality of Life of Older Malaysians (MHQoLOM). Included in the survey were 2980 respondents consisting of Malaysians aged 60 years and over, with both men (n = 1428) and women (n = 1552) represented. Results of t-tests showed older men expressed significantly higher levels of self-rated health and self-esteem than women (p < .01). Separate multivariate regression by gender revealed that age, life-threatening problems, and self-esteem were highly significant predictors of self-rated health among older men and women and explained 18.4% of variance in self-rated health for men and 18.2% for women. In the last step we examined the main effects of gender on self-rated health using General Linear Models (GLM) Univariate by adjusting for age, life-threatening problems, and self-esteem. Results showed an insignificant difference in self-rated health between older men and women (F (1,2715) = 2.26, P = 0.13) only after adjusting for self-esteem. It can be concluded that self-esteem affects responses to self-rated health of older men and women. 相似文献
4.
David Nicholas Hamid R. Jamali M. Paul Huntington Ian Rowlands 《Learned Publishing》2005,18(3):212-220
This paper presents the results of a major investigation by questionnaire of author attitudes towards scholarly publishing, which was funded by the Publisher's Association. Altogether, the views of nearly 4,000 authors were obtained and this paper concerns just those thousand or so authors who accepted the invitation to write freely about their own personal feelings and experiences. Using QSR N6 textual analysis software, their comments were processed and themes extracted. While the rest of the questionnaire, which was formed of closed‐question, tick‐box type questions, clearly must have had some impact on their thinking, the authors had considerable latitude in regard to what they could say. The paper provides a unique opportunity to hear their views directly. The pressing topics turned out to be (in rough order of concern): the peer‐review system, copyright, journal prices, alternative business models for journal publishing, big deals, Elsevier, electronic publishing and digital journals. 相似文献
5.
David Nicholas Director of CIBER Professor at Director of the School of Library Paul Huntington Senior Researcher a founder member of CIBER SLAIS University College London WCE BT UK Hamid R. Jamali a researcher in CIBER SLAIS University College London WCE BT UK 《The Journal of Academic Librarianship》2007,33(6):629-638
The logs of four universities using the OhioLINK journal system were evaluated for a period of fifteen months using deep log analysis methods in order to compare and contrast the information seeking behaviour of their users. Large differences were found, especially between the research and teaching universities. Methodological problems associated with making the comparisons are discussed in some detail especially in terms of defining online sessions. 相似文献
6.
David NICHOLAS Anthony WATKINSON Hamid R. JAMALI Eti HERMAN Carol TENOPIR Rachel VOLENTINE Suzie ALLARD Kenneth LEVINE 《Learned Publishing》2015,28(1):15-21
The article presents one of the main findings of an international study of 4,000 academic researchers that examined how trustworthiness is determined in the digital environment when it comes to scholarly reading, citing, and publishing. The study shows that peer review is still the most trustworthy characteristic of all. There is, though, a common perception that open access journals are not peer reviewed or do not have proper peer‐review systems. Researchers appear to have moved inexorably from a print‐based system to a digital system, but it has not significantly changed the way they decide what to trust. They do not trust social media. Only a minority – although significantly mostly young and early career researchers – thought that social media are anything other than more appropriate to personal interactions and peripheral to their professional/academic lives. There are other significant differences, according to the age of the researcher. Thus, in regard to choosing an outlet for publication of their work, young researchers are much less concerned with the fact that it is peer reviewed. 相似文献
7.
This paper discusses the problem of the fuzzy sliding mode control for a class of disturbed systems. First, a fuzzy auxiliary controller is constructed based on a feedback signal not only to estimate the unknown control term, but also participates in the sliding mode control due to the fuzzy rule employed. Then, we extend our theory into the cases, where some kind of system information can not be obtained, for better use of our theoretical results in real engineering. Finally, some typical numerical examples are included to demonstrate the effectiveness and advantage of the designed sliding mode controller. 相似文献
8.
In this paper, we propose an optimization framework to retrieve an optimal group of experts to perform a multi-aspect task. While a diverse set of skills are needed to perform a multi-aspect task, the group of assigned experts should be able to collectively cover all these required skills. We consider three types of multi-aspect expert group formation problems and propose a unified framework to solve these problems accurately and efficiently. The first problem is concerned with finding the top k experts for a given task, while the required skills of the task are implicitly described. In the second problem, the required skills of the tasks are explicitly described using some keywords but each expert has a limited capacity to perform these tasks and therefore should be assigned to a limited number of them. Finally, the third problem is the combination of the first and the second problems. Our proposed optimization framework is based on the Facility Location Analysis which is a well known branch of the Operation Research. In our experiments, we compare the accuracy and efficiency of the proposed framework with the state-of-the-art approaches for the group formation problems. The experiment results show the effectiveness of our proposed methods in comparison with state-of-the-art approaches. 相似文献
9.
This paper deals with the problem of adaptive output feedback neural network controller design for a SISO non-affine nonlinear system. Since in practice all system states are not available in output measurement, an observer is designed to estimate these states. In comparison with the existing approaches, the current method does not require any information about the sign of control gain. In order to handle the unknown sign of the control direction, the Nussbaum-type function is utilized. In order to approximate the unknown nonlinear function, neural network is firstly exploited, and then to compensate the approximation error and external disturbance a robustifying term is employed. The proposed controller is designed based on strict-positive-real (SPR) Lyapunov stability theory to ensure the asymptotic stability of the closed-loop system. Finally, two simulation studies are presented to demonstrate the effectiveness of the developed scheme. 相似文献
10.
In this paper, we study an adaptive random search method based on continuous action-set learning automaton for solving stochastic optimization problems in which only the noise-corrupted value of function at any chosen point in the parameter space is available. We first introduce a new continuous action-set learning automaton (CALA) and study its convergence properties. Then we give an algorithm for optimizing an unknown function. 相似文献