A sliding mode approach to H∞ synchronization of master–slave time-delay systems with Markovian jumping parameters and nonlinear uncertainties

In this paper, a sliding-mode approach is proposed for exponential H_∞ synchronization problem of a class of master–slave time-delay systems with both discrete and distributed time-delays, norm-bounded nonlinear uncertainties and Markovian switching parameters. Using an appropriate Lyapunov–Krasovskii functional, some delay-dependent sufficient conditions and a synchronization law, which include the master–slave parameters are established for designing a delay-dependent mode-dependent sliding mode exponential H_∞ synchronization control law in terms of linear matrix inequalities. The controller guarantees the H_∞ synchronization of the two coupled master and slave systems regardless of their initial states. Two numerical examples are given to show the effectiveness of the method.     

Digital inclusion and social exclusion: The political economy of value in a networked world

Current debates around user-generated content and its role in wealth generation can be understood as attempts to apply or develop a theory of exploitation or, more broadly, a theory of value. This article seeks to provide a theory based on the network asymmetries of late capitalism, which tend to unevenly distribute network resources through a logic of “digital inclusion.” The mechanisms that enable this asymmetric situation are introduced, and the historical displacements that have given rise to those mechanisms are briefly discussed. The conceptual model that emerges from the analysis reveals the salient features of the contemporary connexionist world that transcend, but do not erase, class boundaries.     

Analyzing noise-induced tracking errors in control systems with saturation: A stochastic linearization approach

Noise Induced Tracking Error (NITE) refers to the tracking error of the mean of the output in feedback control systems with nonlinear instrumentation subject to zero-mean measurement noise. Most of the previous work rely on the stochastic averaging for NITE analysis, the validity of which requires that the bandwidth of the zero mean measurement noise is much higher than that of the system. This is because the results obtained by stochastic averaging are asymptotic with respect to the noise bandwidth. Due to the asymptotic nature of the analysis tool, it is not straightforward to provide a quantitative argument for high bandwidth. An alternative method in the literature that can analyze NITE is stochastic linearization for random input, which is analogous to the well known describing function approach for sinusoidal input. Unlike stochastic averaging, stochastic linearization is not an asymptotic approximation. Therefore, analysis can be carried out for any given noise bandwidth. We carry out NITE analysis using stochastic linearization for a class of LPNI systems that are prone to NITE; identify the system conditions under which the averaging analysis of NITE may yield inaccurate results for a finite noise bandwidth; and prove that the results from the two methods agree as the noise bandwidth approaches infinity. In addition, an existing NITE mitigation strategy is extended based on the proposed method. Numerical examples are given to illustrate the results.     

Developing a road performance index using a Bayesian belief network model

There is a high demand to develop and incorporate decision support tools, by the transportation sectors and other concerned agencies, to improve their infrastructure assets management under shrinking budgets and increasing demands. This paper develops a proof-of-concept Bayesian belief network (BBN) model to rank roads in a network system based on several key performance indicators (KPI) using a probabilistic framework. For a given road network, the proposed tool is capable of ranking or prioritizing the segment of roads for high level management objectives. To demonstrate the application of the proposed model, various scenarios are elaborated and discussed in detail. Finally, the sensitivity analysis is carried out to evaluate the effects of different KPIs.     

Does research using qualitative methods (grounded theory,ethnography, and phenomenology) have more impact?

In spite of the increasing use of qualitative research methods in library and information studies, it is unclear whether using qualitative methods (grounded theory, ethnography, and phenomenology) results in an above average impact in library and information science (LIS). Articles using any of the three qualitative methods published from 2003 to 2013 and indexed in Web of Science in the category of “Information Science & Library Science” (N?=?299) were studied. The number of citations and Mendeley readers for each article was compared to the other articles published in the same journal and same volume using mean normalised rank (rank-1/articles-1). The results showed no statistically significant difference between the citation rates of qualitative articles with those of other articles. Qualitative articles on average had a smaller Mendeley readership than the other articles did and the difference was statistically significant. Given the increasing interest in qualitative methods, it is suggested that LIS schools in their education programs and journals in their editorial policies should put more emphasis on issues related to the rigour of qualitative research.     

The Student Actions Coding Sheet (SACS): An instrument for illuminating the shifts toward student‐centered science classrooms

This study describes the development of an instrument to investigate the extent to which student‐centered actions are occurring in science classrooms. The instrument was developed through the following five stages: (1) student action identification, (2) use of both national and international content experts to establish content validity, (3) refinement of the item pool based on reviewer comments, (4) pilot testing of the instrument, and (5) statistical reliability and item analysis leading to additional refinement and finalization of the instrument. In the field test, the instrument consisted of 26 items separated into four categories originally derived from student‐centered instruction literature and used by the authors to sort student actions in previous research. The SACS was administered across 22 Grade 6–8 classrooms by 22 groups of observers, with a total of 67 SACS ratings completed. The finalized instrument was found to be internally consistent, with acceptable estimates from inter‐rater intraclass correlation reliability coefficients at the p < 0.01 level. After the final stage of development, the SACS instrument consisted of 24 items separated into three categories, which aligned with the factor analysis clustering of the items. Additionally, concurrent validity of the SACS was established with the Reformed Teaching Observation Protocol. Based on the analyses completed, the SACS appears to be a useful instrument for inclusion in comprehensive assessment packages for illuminating the extent to which student‐centered actions are occurring in science classrooms.     

Effect of telenursing on aging perception of Iranian older adults

Background and purpose: The perception of aging is one of the independent predictors of functional disability and mortality in the aged ones, this study was conducted to compare the follow-up of a training program with the use of two in-person and telenursing methods on the perception of aging of the elderly, covered by the comprehensive health centers in Ahvaz city.

Materials and Methods: This quasi-experimental study involved systematic random sampling conducted on 60 elderly persons (aged 60–75 years) who were referred to in Ahvaz. A training program was conducted for all elderly persons for 3 weeks (three sessions per week), which was accompanied with 2 months of six follow-ups for the telephonic follow-up group (Tele-nursing), and two follow-ups for in-person follow-up group. The data were collected with the use of demographic form, Abbreviated Mental Test (AMT), and The Brief Aging Perceptions Questionnaire (B-APQ). Elderly completed the questionnaire at the beginning of the study and 8 weeks later. The data were subsequently analyzed with SPSS software; and P values less than 0.05 were considered significant.

Results: Based on the results, the mean score of perception of aging increased in the study groups after the intervention. This increase was statistically significant only in the intervention group.

Discussion and Conclusion: The telephonic follow-up was more effective on Increasing the perception of aging compared with the in-person follow-up. Therefore, using this method is recommended for the elderly.     

BOOK REVIEW

The application of total quality management (TQM) to the college classroom has been hotly debated. Those critical of its use argue that it is too confining and would stifle academic creativity. Such assessments are self‐defeating and encourage educators to turn their backs on a useful tool before even attempting to use it. Properly used according to the methods described herein, TQM can be effective in the classroom and prove to be a valuable augmentation to traditional academic planning methods     

Noncredit Program Data Collection at Community Colleges: A Scoping Review

ABSTRACT

Noncredit enrollment at community colleges has grown significantly over the past two decades. However, unlike credit bearing programs, noncredit programs are seldomly empirically examined and evaluated, particularly those that are not grant funded. The lack of data results in a gap in knowledge about program effectiveness, as well as the students who participate in noncredit programs, it is difficult to objectively discuss the effectiveness of programs and develop valid policies to support them. This paper specifically aims to: (a) map the relevant literature regarding noncredit program data collection; (b) summarize existing knowledge about data collection processes; and (c) identify existing knowledge gaps in what is known about noncredit data collection. An established five stage process for conducting a scoping review guided the process: (a) identifying the research question; (b) identifying the related body of literature; (c) study selection; (d) presenting of data; and lastly, (e) collating, summarizing, and reporting results. The majority of data collected were head counts, types of courses offered and minimal demographic information. The results also show that, despite higher enrollments and the popularity of programs, there is a lack of comprehensive information on student needs. Thus, it is crucial to develop a standardized data collection system for all noncredit programs; collect data at a student level; and provide more detailed information regarding enrollment, completion, and outcomes such as employment and wage gains, as well as qualitative factors such as student satisfaction.