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121.
This study considers merging dynamical networks (relative sensing networks in this paper) in terms of a stability margin criterion. The main motivation of this consideration is that merging can cause a significant drop in the stability margin of merged network with respect to the original networks initially with ample stability margins. In this paper, various types of network merging (i.e. undirected/directed homogeneous/heterogeneous dynamical network merging via one-way/two-way links) are analysed to show their effects on the stability margin. In particular, it is shown that (1) merging with one-way links yields the stability margin less than the original networks’; (2) merging undirected homogeneous networks with two-way links results in a stability margin being at least a quantity solely characterized by the positive realness (PRness) of SISO (Single-Input-Single-Output) local dynamics; (3) the quantity depends both on the PRness of SISO local dynamics and the eigenvalues of Laplacian matrix, in case of merging directed homogeneous networks with two-way links; (4) two-way merging using multiple nodes may allow for a large increase in the stability margin; and (5) merging heterogeneous networks may be simply treated as merging homogeneous networks by exploiting the design of link dynamics. Several numerical results are presented to show their consistency with the performed analysis. 相似文献
122.
Sung Hyun Kim 《Journal of The Franklin Institute》2021,358(2):1553-1577
This paper is concerned with the problem of designing a dissipative control for generalized nonhomogeneous Markovian jump fuzzy systems (MJFSs) that can cover both piecewise-homogeneous MJFSs and nonhomogeneous MJFSs through the use of dual modes, i.e., plant and higher-level modes. Based on a dual-mode-dependent fuzzy control law within a nonparallel distributed compensation (non-PDC) scheme, the nonquadratic stabilization conditions are first formulated in terms of multi-parameterized linear matrix inequalities (M-PLMIs), and then be transformed into a finite set of solvable LMIs without reducing M-PLMIs to PLMIs. Further, since the proposed relaxation technique can address the transition probabilities of plant and higher-level modes at once, the characteristics on mutual dependence between dual modes are fully incorporated into the nonquadratic stabilization conditions. Two illustrative examples are given to show the validity of the proposed approach. 相似文献
123.
Professors contribute to Institutional Repositories (IRs) to make their materials widely accessible in keeping with the benefits of Open Access. However, universities' commitment to IRs depends on building trust with faculty and solving copyright concerns. Digital preservation and copyright management in IRs should be strengthened to increase faculty participation. 相似文献
124.
Yong-Mi Kim 《The Journal of Academic Librarianship》2011,37(1):9-18
Users across academic disciplines utilize different information sources based on the resource's usefulness and relevance. This study's findings show that users from arts and sciences disciplines are much more likely to utilize university library website resources and printed materials than business users who heavily rely on commercial websites. 相似文献
125.
Kim Normann Andersen Rony Medaglia Ravi Vatrapu Helle Zinner Henriksen Robin GauldAuthor vitae 《Government Information Quarterly》2011,28(4):439-445
Assessing e-government responsiveness is one of the major gaps in the currently dominant e-government maturity models. While we have a relatively large pool of models focusing on technological and organizational integration from a supply side perspective, measures of responsiveness of e-government systems from a user perspective are still lacking. Replicating a study from New Zealand and Australia, this study explores the response time and quality of e-mail response in Danish local and central governments (N = 175). Despite that Denmark is high ranking in international benchmark studies, we find that one third of central government agencies did not respond at all, and close to 80% of the ministries provided none or incomplete answers. Local government responds faster and provides answers that are more complete and accurate than those provided by central government. Implications for e-government are discussed. 相似文献
126.
The successful encapsulation of human hepatocellular carcinoma (HepG2) cells would greatly assist a broad range of applications in tissue engineering. Due to the harsh conditions during standard chitosan fiber fabrication processes, encapsulation of HepG2 cells in chitosan fibers has been challenging. Here, we describe the successful wet-spinning of chitosan-alginate fibers using a coaxial flow microfluidic chip. We determined the optimal mixing conditions for generating chitosan-alginate fibers, including a 1:5 ratio of 2% (w∕w) water-soluble chitosan (WSC) solution to 2% (w∕w) alginate solution. Ratio including higher than 2% (w∕w) WSC solution increased aggregation throughout the mixture. By suspending cells in the WSC-alginate solution, we successfully fabricated HepG2 cell-laden fibers. The encapsulated HepG2 cells in the chitosan-alginate fibers were more viable than cells encapsulated in pure alginate fibers, suggesting that cross-linked chitosan provides a better environment for HepG2 cells than alginate alone. In addition, we found that the adhesion of HepG2 cells on the chitosan-alginate fiber is much better than that on the alginate fibers. 相似文献
127.
Medic and colleagues (Medic, Starkes, & Young, 2007) found that relatively younger cohorts of Masters athletes had higher participation rates and achieved higher performances compared with a relatively older cohort. Considering that Medic and colleagues' (2007) study was cross-sectional in nature, the purpose of this investigation was to employ a retrospective longitudinal study design to examine the participation rates of Masters swimmers as a function of an individual's constituent year within any 5-year age category over a period of 6 years. Using archived data from the 2003 to 2009 US Masters Short Course National Championships, swimmers' attendance was followed for a period of six consecutive years. Results indicated that a participation-related relative age effect was observed among swimmers who, over a period of 6 years, competed in either at least one championship (N = 2596; Cochran's Q? = 64.16, r(s) = -0.92, both P < 0.0001) or at least three championships (N = 441; Cochran's Q? = 47.51, r(s) = -0.91, both P < 0.0001). Overall, effect size analyses indicated that the odds of a Masters swimmer participating in the championship during the first constituent year of any 5-year age category was more than two times greater than the odds of that athlete participating during the fifth constituent year. 相似文献
128.
Alghamdi Amani Khalaf H. Al Ghamdi Kholoud S. Kim Sun Young 《Journal of Science Education and Technology》2022,31(5):583-593
Journal of Science Education and Technology - It is of great importance that science educators teach COVID-19 and related pandemics to boost students’ scientific literacy. A mixed methods... 相似文献
129.
This study scrutinizes Asia Pacific Education Review (APER) that has been weathered 13 years of journey from its inception. Numerically, 504 peer-reviewed articles have been published so far, and 0.5 of impact factor has been achieved. This article recollects the history of APER, overhaul the accomplishment and shortcomings of it. Through an overview of the annually submitted and published articles, 14 domains of research area, research methods, and the demographics of contributors were examined; 30 nationalities of authors’ papers were published, and 2/3 of articles used quantitative research method. The most published domains were educational administration and policy, educational psychology and special education, and higher education; however, the most cited articles covered all research area of education impartially. This study also suggested APER’s contribution to the advancement of education research community internationally and interdisciplinarily. 相似文献
130.
Many household consumables contain volatile organic compounds(VOCs)as the active ingredient.Long term exposure to VOCs could cause various health problems,especially to the respiratory system.Graphene has attracted a lot of attention recently for its potential to be used as sensing material for VOCs.In this project we have constructed graphene/PVA composite based gas sensors for VOC detection.It was perceived that the polymer could introduce better selectivity to the sensor.Results suggest that the proposed sensor is highly sensitive to low molecular weight VOCs and that the manner in which the sensor respond to the vapour depends on the polarity or hydrophobicity of the vapour. 相似文献