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891.
In a multi-agent framework, distributed optimization problems are generally described as the minimization of a global objective function, where each agent can get information only from a neighborhood defined by a network topology. To solve the problem, this work presents an information-constrained strategy based on population dynamics, where payoff functions and tasks are assigned to each node in a connected graph. We prove that the so-called distributed replicator equation (DRE) converges to an optimal global outcome by means of the local-information exchange subject to the topological constraints of the graph. To show the application of the proposed strategy, we implement the DRE to solve an economic dispatch problem with distributed generation. We also present some simulation results to illustrate the theoretic optimality and stability of the equilibrium points and the effects of typical network topologies on the convergence rate of the algorithm. 相似文献
892.
893.
G. D. Sardana 《Performance Improvement》2008,47(7):31-40
Managers look for measures that represent an integrated performance. These should lead to an analysis of unsatisfactory performance. Performance measurement and its evaluation is the first step toward formulating any plan for improvement. This article examines the imperatives of a good measurement system and presents a framework to measure business performance. 相似文献
894.
Carol G. Hixson 《Cataloging & classification quarterly》2020,58(3-4):294-302
AbstractThe beginnings and the early years of the Program for Cooperative Cataloging (PCC) had a profound impact on the approach taken to cataloging in North America and around the world. The commitment to standards, cooperation, and expanded access also had an impact that went far beyond cataloging operations. One library dean traces the evolution of her vision and contemplates how the PCC’s principles have shaped her entire career and have affected the libraries in which she has worked. 相似文献
895.
The aim of the study was to deepen our understanding of how related multiscreening affects audience memory and persuasion. A survey was administered after a live television show. The results showed that the higher the perceived relatedness of the multi-screen activity, the more persuasive the message. This effect was mediated by subsequent attention to television content, program involvement, and attention to the commercial break. The model was replicated for three different multiscreen activities: social media use, chatting, and information search. Furthermore, it was found that related multiscreening increased the likelihood of respondents staying tuned to the television after the show. 相似文献
896.
Samuel J. Callaghan Robert G. Lockie Warren A. Andrews Robert F. Chipchase Sophia Nimphius 《Sports biomechanics / International Society of Biomechanics in Sports》2020,19(3):307-321
AbstractThis study assessed the reliability and validity of segment measured accelerations in comparison to front foot contact (FFC) ground reaction force (GRF) during the delivery stride for cricket pace bowlers. Eleven recreational bowlers completed a 30-delivery bowling spell. Trunk- and tibia-mounted inertial measurement units (IMUs) were used to measure accelerations, converted to force, for comparisons to force plate GRF discrete measures. These measures included peak force, impulse and the continuous force–time curve in the vertical and braking (horizontal) planes. Reliability and validity was determined by intra-class correlation coefficients (ICC), coefficient of variation (CV), Bland–Altman plots, paired sample t-tests, Pearson’s correlation and one-dimensional (1D) statistical parametrical mapping (SPM). All ICC (0.90–0.98) and CV (4.23–7.41%) were acceptable, except for tibia-mounted IMU braking peak force (CV = 12.44%) and impulse (CV = 18.17%) and trunk vertical impulse (CV = 17.93%). Bland–Altman plots revealed wide limits of agreement between discrete IMU force signatures and force plate GRF. The 1D SPM outlined numerous significant (p < 0.01) differences between trunk- and tibia-located IMU-derived measures and force plate GRF traces in vertical and braking (horizontal) planes. The trunk- and tibia-mounted IMUs appeared to not represent the GRF experienced during pace bowling FFC when compared to a gold-standard force plate. 相似文献
897.
Kristen MacKenzie-Shalders Jaimon T. Kelly Daniel So Vernon G. Coffey Nuala M. Byrne 《Journal of sports sciences》2020,38(14):1635-1649
ABSTRACT The systematic review and meta-analysis evaluated the effect of aerobic, resistance and combined exercise on RMR (kCal·day-1) and performed a methodological assessment of indirect calorimetry protocols within the included studies. Subgroup analyses included energy/diet restriction and body composition changes. Randomized control trials (RCTs), quasi – RCTs and cohort trials featuring a physical activity intervention of any form and duration excluding single exercise bouts were included. Participant exclusions included medical conditions impacting upon RMR, the elderly (≥65 years of age) or pregnant, lactating or post-menopausal women. The review was registered in the International Prospective Register of Systematic Reviews (CRD 42,017,058,503). 1669 articles were identified; 22 were included in the qualitative analysis and 18 were meta-analysed. Exercise interventions (aerobic and resistance exercise combined) did not increase resting metabolic rate (mean difference (MD): 74.6 kCal·day-1[95% CI: ?13.01, 161.33], P = 0.10). While there was no effect of aerobic exercise on RMR (MD: 81.65 kCal·day-1[95% CI: ?57.81, 221.10], P = 0.25), resistance exercise increased RMR compared to controls (MD: 96.17 kCal·day-1[95% CI: 45.17, 147.16], P = 0.0002). This systematic review effectively synthesises the effect of exercise interventions on RMR in comparison to controls; despite heterogenous methodologies and high risk of bias within included studies. 相似文献
898.
ABSTRACTBuilding upon the sociotechnical perspective presented by Lewis and Westlund (2015, “Actors, Actants, Audiences, and Activities in Cross-media News Work: A Matrix and a Research Agenda.” Digital Journalism 3 (1): 19–37. doi:10.1080/21670811.2014.927986), this study examines organizational dynamics, technological affordances and professional challenges of engaged journalism practices by analyzing how Hearken, one of the most celebrated audience engagement companies, and its tools and services are being implemented in 15 U.S. news organizations. This framework identifies Hearken and organizations like it as important “external actors” providing technological “actants” that are shaping how newsrooms report the news by providing ways for audiences to be brought into producing the news, particularly during the earlier phases of the reporting process. Based on in-depth interviews, we find that nearly every news organization in our sample reports some measure of success by using Hearken for involving audience members throughout the production of news. At the same time, we also identify how this implementation is significantly shaped by organizational imperatives and the models particular organizations create for producing audience-centric news work. Ultimately, this study presents a partial update to the decades-long literature on participatory journalism by suggesting that engaged journalism practices actually create opportunities for meaningful audience involvement. 相似文献
899.
The proliferation of sports science and technological innovation within performance settings has precipitated the generation of increasing volumes of data to aid athletes. Copious data production has also perpetuated the privileging of scientific information, and a ‘thirst’ for ‘more data’ as an unproblematic ‘truth’. Of significance is not merely the use of technology for the production of data-for-data's sake, or the utility of data for a greater cause (e.g. the good of the team), but the quest for personalised data for individual athletes to be analysed, and reflected upon ad nauseam. Furthering scholarship on disciplining bodies, we argue that increased technological consumption, and the related excessive quantification of athletes’ bodies via data production, adds further insecurity into performance sports work. Finally, attention is given to the cultural step-change new techno-dispositions may now present. 相似文献
900.
A nationwide survey of county departments of social services revealed a need for medical services and consultation to child protection units. Over 92% of the 84 counties surveyed stated they had a problem meeting their medical needs and would be willing to hire a physician assistant as medical consultant to their county's child protection team. No county refused to consider a physician assistant, but 7% felt their medical requirements were being met. Needs the counties most commonly identified were providing parent education/anticipatory guidance (69%), interviewing (65.5%), interpreting medical information to a multidisciplinary child protection team (58.3%), review of medical records (45.8%), and physical examinations (42.9%). Over 17% of the counties had money to fund a full-time physician assistant, and over 60% of the counties could provide a partial salary, with 70.5% willing to share a salary with adjacent counties and 76.9% with the county's public health department. 相似文献