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This paper addresses an output feedback control problem for a class of networked control systems (NCSs) with a stochastic communication protocol. Under the scenario that only one sensor is allowed to obtain the communication access at each transmission instant, a stochastic communication protocol is first defined, where the communication access is modeled by a discrete-time Markov chain with partly unknown transition probabilities. Secondly, by use of a network-based output feedback control strategy and a time-delay division method, the closed-loop system is modeled as a stochastic system with multi-time-varying delays, where the inherent characteristic of the network delay is well considered to improve the control performance. Then, based on the above constructed stochastic model, two sufficient conditions are derived for ensuring the mean-square stability and stabilization of the system under consideration. Finally, two examples are given to show the effectiveness of the proposed method.

Background When the Zika virus outbreak became a global health emergency in early 2016, the scientific community responded with an increased output of Zika-related research. This upsurge in research naturally made its way into academic journals along with editorials, news, and reports. However, it is not yet known how or whether these scholarly communications were distributed to the populations most affected by Zika. Methodology/Principal findings To understand how scientific outputs about Zika reached global and local audiences, we collected Tweets and Facebook posts that linked to Zika-related research in the first six months of 2016. Using a language detection algorithm, we found that up to 90% of Twitter and 76% of Facebook posts are in English. However, when none of the authors of the scholarly article are from English-speaking countries, posts on both social media are less likely to be in English. The effect is most pronounced on Facebook, where the likelihood of posting in English is between 11 and 16% lower when none of the authors are from English-speaking countries, as compared to when some or all are. Similarly, posts about papers written with a Brazilian author are 13% more likely to be in Portuguese on Facebook than when made on Twitter. Conclusions/Significance Our main conclusion is that scholarly communication on Twitter and Facebook of Zika-related research is dominated by English, despite Brazil being the epicenter of the Zika epidemic. This result suggests that scholarly findings about the Zika virus are unlikely to be distributed directly to relevant populations through these popular online mediums. Nevertheless, there are differences between platforms. Compared to Twitter, scholarly communication on Facebook is more likely to be in the language of an author’s country. The Zika outbreak provides a useful case-study for understanding how scientific outputs are communicated to relevant populations. Our results suggest that Facebook is a more effective channel than Twitter, if communication is desired to be in the native language of the affected country. Further research should explore how local media—such as governmental websites, newspapers and magazines, as well as television and radio—disseminate scholarly publication.

This introduction highlights the diversity of national localities, research methods, case studies, and topics covered by the papers selected for inclusion in the special issue on “Planning and foresight methodologies in emergency preparedness and management.” It then provides a detailed summary of each study, emphasizing what the editors feel are the most important contributions. Concluding remarks include a call for future studies that are needed. An example is planning for ways of supporting and integrating citizen participation in all phases of crisis management, a topic that is missing from this collection.

Sustainability of engineering programs in Pakistan remains in jeopardy due to different approaches used for degree programs. Whilst most institutions follow semester system and fulfil the relevant requirements, a few still insist in annual system. Pakistan engineering Council has developed an accreditation program which is currently being implemented at all institutions offering BE Environmental Engineering Degree. This paper highlights the facts that incorporation of ISO 14001 requirements into the existing accreditation program will not only help bridging the gap between institutional approaches but also make all the programs in conformity with international programs and our graduates will have better prospects of success in industry as well as in graduate studies at renowned international institutions. This will not only facilitate communication amongst similar institutions but exchange of faculty as well as students at any stage will also be promoted.

Traditionally metallic waveguide filters have been used commercially for microwave applications. These filters have very reduced insertion losses within their operating frequency band and their construction is considerably economic. On the other hand, metallic filters have significant drawbacks, especially when they are designed for satellite and other spatial applications, since their weight and size may very often be too high and due to the lack of atmosphere, the Multipactor effect limits considerably the power that the filters can handle. This problems can be reduced by using new topologies of H-plane waveguide filters loaded with dielectric resonators. Nevertheless the analysis and design of these filters is far more complex than the one of all metallic filters, due to their special topology. Efficient mathematical tools are required for this analysis and this paper presents a new hybrid mode matching method for the efficient analysis of rods in waveguided structures. © 2011 Elsevier Ltd. All rights reserved.

Geologic carbon dioxide (CO 2 ) storage verification tests by the U.S. Department of Energy’s (DOE’s) seven Regional Carbon Sequestration Partnerships (RCSPs) provided the experience base for the Public Outreach and Education for Carbon Storage Projects, a best practices manual, published in December 2009. This paper summarizes these outreach best practices; discusses their application in Aquistore, a greenfield CO 2 storage project under way in western Canada; and reviews the implications for applying the best practices to new projects during the Development Phase of the DOE’s RCSP Program.

Together with the optimal linearization technique, a blind-channel equalization for the extended-Kalman-filter-based chaotic communication is proposed in this paper. First, the optimal linearization technique is utilized to find the exact linear models of the chaotic system at operating states of interest. The proposed blind-channel equalization is formulated as a mixed nonlinear parameter and state estimation problem by an autoregressive (AR) model. The channel coefficients of a fading and multipath channel can be represented by an AR process. Then, an extended Kalman filter algorithm is utilized to reduce the effect of channel noise. By using the extended Kalman filter, the channel coefficients and the state of the system, which is the signal before going through the channel, can be estimated. The stability problem of the proposed blind-channel equalization is also addressed. Numerical examples and simulations are given to show the effectiveness and speed of convergence for the proposed methodology.

In this paper, a powerful communication scheme is introduced to efficiently meet different communication requirements for behavioural synthesis from VHDL. The algorithmic description of the system behaviour is specified through a set of cooperating VHDL processes. Communication between processes is provided by the definition of a message-passing communication scheme, to efficiently manage both synchronised and unsynchronised data exchange. A way to effectively map message passing to shared memory for system synthesis is also presented. The proposed data communication scheme has been successfully tested with the VHDL model of the congestion control of an ATM node.