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111.
This paper is devoted to the non-fragile exponential synchronization problem of complex dynamical networks with time-varying coupling delays via sampled-data static output-feedback controller involving a constant signal transmission delay. The dynamics of the nodes contain s quadratically restricted nonlinearities, and the feedback gain is allowed to have norm-bounded time-varying uncertainty. The control design is based on a Lyapunov–Krasovskii functional, which consists of the sum of terms assigned to the individual nodes, i.e., it is constructed without merging the complex dynamical network’s nodes into a single large-scale system. In this way, the proposed design method has substantially reduced computational complexity and improved conservativeness, and guaranties non-fragile exponential stability of the error system. The sufficient stability condition is expressed in terms of linear matrix inequalities that are solvable by standard tools. The efficiency of the proposed method is illustrated by numerical examples. 相似文献
112.
113.
A microfluidic device that is able to perform dielectric spectroscopy is developed. The device consists of a measurement chamber that is 250 μm thick and 750 μm in radius. Around 1000 cells fit inside the chamber assuming average quantities for cell radius and volume fraction. This number is about 1000 folds lower than the capacity of conventional fixtures. A T-cell leukemia cell line Jurkat is tested using the microfluidic device. Measurements of deionized water and salt solutions are utilized to determine parasitic effects and geometric capacitance of the device. Physical models, including Maxwell-Wagner mixture and double shell models, are used to derive quantities for sub-cellular units. Clausius-Mossotti factor of Jurkat cells is extracted from the impedance spectrum. Effects of cellular heterogeneity are discussed and parameterized. Jurkat cells are also tested with a time domain reflectometry system for verification of the microfluidic device. Results indicate good agreement of values obtained with both techniques. The device can be used as a unique cell diagnostic tool to yield information on sub-cellular units. 相似文献
114.
The literature has identified barriers with library staff as one of the important barriers affecting academic activities of students and also recognized the relationship of various academic and demographic characteristics of students with it. The emotions management skills of students may be one of the possible correlates of the barriers with library staff. This study was designed to investigate the levels of barriers with library staff and emotions management skills as well as their possible correlation using two standardized scales. The data were collected from the final year undergraduate agriculture students. The results confirmed the existence of barriers with library staff among the participants of both genders experiencing the same level of anxiety. The participants scored 3.75 (average) on the emotions management scale. The results also revealed significantly negative correlation between emotions management skills and barriers with library staff among these students. These results have many practical implications in the sphere of academic librarianship. 相似文献
115.
Seyed Amin Mirlohi Falavarjani Fattane Zarrinkalam Jelena Jovanovic Ebrahim Bagheri Ali A. Ghorbani 《Information processing & management》2019,56(6):102070
The ever increasing presence of online social networks in users’ daily lives has led to the interplay between users’ online and offline activities. There have already been several works that have studied the impact of users’ online activities on their offline behavior, e.g., the impact of interaction with friends on an exercise social network on the number of daily steps. In this paper, we consider the inverse to what has already been studied and report on our extensive study that explores the potential causal effects of users’ offline activities on their online social behavior. The objective of our work is to understand whether the activities that users are involved with in their real daily life, which place them within or away from social situations, have any direct causal impact on their behavior in online social networks. Our work is motivated by the theory of normative social influence, which argues that individuals may show behaviors or express opinions that conform to those of the community for the sake of being accepted or from fear of rejection or isolation. We have collected data from two online social networks, namely Twitter and Foursquare, and systematically aligned user content on both social networks. On this basis, we have performed a natural experiment that took the form of an interrupted time series with a comparison group design to study whether users’ socially situated offline activities exhibited through their Foursquare check-ins impact their online behavior captured through the content they share on Twitter. Our main findings can be summarised as follows (1) a change in users’ offline behavior that affects the level of users’ exposure to social situations, e.g., starting to go to the gym or discontinuing frequenting bars, can have a causal impact on users’ online topical interests and sentiment; and (2) the causal relations between users’ socially situated offline activities and their online social behavior can be used to build effective predictive models of users’ online topical interests and sentiments. 相似文献
116.
Christopher Ali 《The Communication Review》2013,16(4):249-270
ABSTRACTDrawing on Buckingham’s observation that academic research either has to become public knowledge or its originators must have a high visibility in the public realm before their research can find inclusion into policymaking processes, this article offers a variety of examples of how academics have managed to bridge the gap between media and communication policy scholarship and policymaking. Contrary to the long-standing belief that policy impact is extremely difficult and rare to achieve, we argue that junior scholars have many opportunities to have their work become part of the policymaking process through new forms of conversation, collaboration, coalition-building, changing perceptions of public knowledge, and a more conceptual understanding of impact. 相似文献
117.
Liv Randi Opdal Siri Wormnæs Ali Habayeb 《International Journal of Disability, Development & Education》2001,48(2):143-162
The present study explored teachers' opinions about the inclusion of students with disabilities and special needs in regular primary schools in a Palestinian context, and factors that influenced such opinions. The sample consisted of 90 teachers at six schools. Eighty-seven (97%) of them had students with disabilities or special needs in their classes. Fifty-four (60%) of the teachers were of the opinion that students with disabilities and special needs should have an opportunity to attend public schools. Opinion-related factors were identified and compared to results of previous studies. Eighty-one (90%) of the teachers expressed a need for changes in the public schools in order to meet the needs of students with disabilities and special needs. Their focus of interest for building their own competence was on knowledge and skills that could empower them as teachers, not on knowledge about the students' disabling impairments. 相似文献
118.
Mahdi Dehghan Maryam Biabani Ahmad Ali Abin 《Information processing & management》2019,56(3):1067-1079
Cost optimization continues to be a critical concern for many human resources departments. The key is to balance between costs and business value. In particular, computer science organizations prefer to hire people who are expert in only one skill area and have a slight superficial knowledge in other areas that gives them the ability to collaborate across different aspects of project. Community Question Answering networks provide good platforms for people and organizations to share knowledge and find experts. An important issue in expert finding is that an expert has to constantly update his knowledge after being saturated in his field of expertise to still be identified as expert. A person who fails to preserve his expertise is likely to lose his expertise. This work justifies this question that does take the concept of time into account improve the quality of expertise retrieval. We propose a new method for T-shaped expert finding that is based on temporal expert profiling. The proposed method takes the temporal property of expertise into account to mine the shape of expertise for each candidate expert based on his profile. To this end, for each candidate expert, we take snapshots of his expertise trees at regular time intervals and learn the relation between temporal changes in different expertise trees and candidates’ profile. Finally, we use a filtering technique that is applied on top of the profiling method, to find shape of expertise for candidate experts. Experimental results on a large test collection show the superiority of the proposed method in terms of quality of results in comparison with state-of-the-art. 相似文献
119.
Paula G. Purnell Parveen Ali Nurun Begum Marilyn Carter 《Early Childhood Education Journal》2007,34(6):419-424
This article investigates how instructors can utilize the integration of early literacy skills and the arts to cultivate the
appreciation and celebration of cultures in early childhood classrooms. The theoretical framework is developed through three
personal accounts establishing a rationale for the importance of a viable home to school connection for young children. Finally,
the suggested activities support the transference of theory into classroom practice. 相似文献
120.
Reactive oxygen species (ROS) are cytotoxic at higher concentration resulting in cell death, mutations, chromosomal aberrations
or carcinogenesis. In this study DNA was modified by singlet oxygen and superoxide anion radicals generated by illumination
of riboflavin under 365 nm UV-light. The modified DNA induced high titre antibodies in experimental animals. In enzyme immunoassay,
serum antibodies from cancer patients (n = 34) showed a higher recognition of the modified DNA, as compared to the native form. This was further confirmed by the
gel-shift assay. Immune IgG were used as a probe to detect oxidative lesions in the DNA of cancer patients. DNA isolated from
lymphocytes of cancer patients proved to be an appreciable inhibitor of the experimentally induced antibodies against the
ROS-DNA. This indicates the presence of oxidative lesions in the DNA obtained from cancer patients. The results show that
ROS induced oxidative damage to DNA in cancer patients generate neo-epitopes that are alien for the immune system, resulting in autoantibody formation. 相似文献