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931.
In this paper we study a multi-channel network, each station of which is equipped with a network interface that has a receiver buffer of multiple packets. In this way, each station is able to receive multiple packets per time instant. We adopt a synchronous access protocol which is affected by the collisions over the multiple channels and the destination conflicts. The proposed protocol performance crucially depends on the size of the receiver buffer since it determines the packet rejection probability at destination. An analytical probabilistic model based on a Markovian process is adopted for the performance measures derivation by means of closed mathematical formulas. The proposed protocol is compared to relative ones that either totally ignore the receiver collisions or assume a receiver buffer of a single packet capacity. The numerical results show that the increase of the receiver buffer size improves the performance decisively, resulting in higher throughput and lower delay and rejection probability. Also, it is shown that the appropriate receiver buffer size per station in order for the rejections at destination to be effectively eliminated is not unlimited but is limited to three packets for 0.1% accepted maximum level of rejection probability. 相似文献
932.
933.
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
934.
İlke Ali Gürses Ahmet Ertaş Başak Gürtekin Osman Coşkun Mehmet Üzel Özcan Gayretli Mehmet Selman Demirci 《Anatomical sciences education》2019,12(4):370-385
Little is known regarding the profiles of whole body donors in Muslim majority countries where donation is scarce. Therefore, this study aims to profile registered donors in Turkey by means of a survey. The explored data could be used to improve ongoing campaign efforts and ethical practices such as commemoration services. Registered donors of the donation programs at the two faculties of medicine of Istanbul University were compared with the national population and a cluster analysis was performed to reveal any concealed sub-groups. Data from 188 respondents were analyzed. The majority of registered donors were married (42%), male (65.4%), aged over 50 years (76%), held a tertiary education degree (49.7%), and were irreligious (58.5%). Cluster analysis revealed two groups with significantly different educational levels, marital statuses, and religious choices. Regarding whether their bodies could be used for education or research, the majority (64.5%) of the respondents left the decision to the anatomy department. Similarly, 73.8% approved indefinite use of their organs, body parts and/or skeletons. The respondents were also willing to share their medical history (94.2%) and personal information (81.6%) if needed. Motivational themes for body donation including usefulness, impermanence, religion, awareness, and kinship were devised after a thematic analysis. Among the respondents, 56.5% were registered organ donors and 63.3% were frequent blood donors. The results of this study provide data that may help revising informed consent forms, developing and implementing thanksgiving ceremonies, and selecting additional targets for supporting body donation campaign activities such as organ and blood donation units. 相似文献
935.
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
936.
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
937.
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
938.
939.
Disability laws in Saudi Arabia mandate that higher education institutions provide support for special needs learners in order to ensure educational opportunities equivalent to opportunities for their nondisabled peers. These institutions experience challenges, however, in providing the necessary support to undergraduate and postgraduate students with learning disabilities (LDs). We conducted an exploratory study to assess educational support requirements and affordances for undergraduate and postgraduate students with LDs attending institutions of higher education in Saudi Arabia. We completed semistructured interviews with 22 special needs learners diagnosed with a LD (16 undergraduate and six postgraduate). The findings suggest that additional support services are needed for undergraduate and postgraduate students with LDs attending Saudi institutions of higher education. 相似文献
940.
G. A. Cherednichenko 《Russian Education & Society》2014,56(8):37-61
Research on young blue-collar workers in Russia indicates that a large percentage of them continue to improve their educational qualifications during the first five years of employment, but that it declines after that time. The two most frequent reasons for upgrading their skills are a desire to leave blue-collar employment, and to increase the chances for promotion to higher skill levels and higher pay. 相似文献