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Zhu W.,Chongqing University of Posts and Telecommunications | Zhu W.,New York University | Jiang Z.-P.,New York University | Feng G.,City University of Hong Kong | Feng G.,Abdulaziz University
Automatica | Year: 2014

In this paper, the event-based consensus problem of general linear multi-agent systems is considered. Two sufficient conditions with or without continuous communication between neighboring agents are presented to guarantee the consensus. The advantage of the event-based strategy is the significant decrease of the number of controller updates for cooperative tasks of multi-agent systems involving embedded microprocessors with limited on-board resources. The controller updates of each agent are driven by properly defined events, which depend on the measurement error, the states of its neighboring agents and an arbitrarily small threshold. It is shown that the controller updates for each agent only trigger at its own event time instants. A simulation example is presented to illustrate the theoretical results. © 2013 Elsevier Ltd. All rights reserved.

Argyros I.K.,Cameron University | Cho Y.J.,Gyeongsang National University | Cho Y.J.,Abdulaziz University
Numerical Functional Analysis and Optimization | Year: 2014

In this article, we provide a semilocal analysis for the Steffensen-type method (STTM) for solving nonlinear equations in a Banach space setting using recurrence relations. Numerical examples to validate our main results are also provided in this study to show that STTM is faster than other methods ([7, 13]) using similar convergence conditions. © 2014 Copyright Taylor & Francis Group, LLC.

Al-Tamimi A.-M.S.,Abdulaziz University | Ghabbour H.A.,King Saud University | Ghabbour H.A.,Mansoura University | El-Emam A.A.,King Saud University
Zeitschrift fur Kristallographie - New Crystal Structures | Year: 2016

C16H19N3O, orthorhombic, Pna21 (no. 33), a = 8.0381(5) Å, b = 10.4499(8) Å, c = 17.1228(13) Å, V = 438.27(18) Å, Z = 4, Rgt(F) = 0.0499, wRref(F2) = 0.1105, T = 100 K. © 2016 Abdul-Malek S. Al-Tamimi et al., published by De Gruyter.

Al-Abdullah E.S.,King Saud University | Ghabbour H.A.,King Saud University | Ghabbour H.A.,Mansoura University | Alkahtani H.M.,King Saud University | And 2 more authors.
Zeitschrift fur Kristallographie - New Crystal Structures | Year: 2016

C21H29N3S, orthorhombic, Pbca (No. 61), a = 9.8658(7) Å, b = 11.7298(9) Å, c = 31.960(2) Å, V = 3698.5(5) Å3, Z = 8, Rgt(F) = 0.0644, wRref(F2) = 0.1684, T = 100 K. © 2016 Ebtehal S. Al-Abdullah et al., published by De Gruyter.

Eskander A.,University of Toronto | Merdad M.,University of Toronto | Merdad M.,Abdulaziz University | Freeman J.L.,University of Toronto | Witterick I.J.,University of Toronto
Thyroid | Year: 2013

Background: There remains controversy surrounding the extent of lateral neck dissection required in patients with papillary thyroid cancer (PTC) and suspicious or confirmed metastatic lateral neck lymphadenopathy. The evidence for this clinical dilemma has never been reviewed systematically nor has there been an attempt to meta-analyze the data by lymph node levels to better characterize the pattern of spread. Methods: This meta-analysis used MEDLINE and EMBASE including all cohort studies reporting the pattern of lateral neck disease in patients who underwent a neck dissection for clinically, radiographically, or cytologically suspicious or confirmed metastatic lymphadenopathy for PTC. Our main outcome was the number of patients with positive involvement at a given level as a percentage of the cohort of patients with positive lateral neck disease, each level being measured separately. Results: Eighteen studies with a total of 1145 patients and 1298 neck dissections were included in our meta-analysis. Levels IIa and IIb had disease in 53.1% [95% confidence interval (CI) 46.6-59.5%] and 15.5% [CI 8.2-27.2%], respectively. Studies that did not distinguish between level IIa and IIb or in which both were collapsed into one category showed a total level II involvement of 53.4% [CI 49.7-57.1%]. Level III and level IV were involved in 70.5% [CI 67.0-73.9%] and 66.3% [CI 61.4-70.9%] of specimens. Studies that did not distinguish between level Va and Vb or in which both were collapsed into one category showed a total level V involvement of 25.3% [CI 20.0-31.5%]. Levels Va and Vb had positivity in 7.9% [CI 2.8-20.0%] and 21.5% [CI 7.7-47.6%], respectively, but had only three studies that could be meta-analyzed. Conclusions: This systematic review of the literature and meta-analysis of the pattern of spread indicates significant rates of lymph node metastasis to all lateral neck levels in patients with PTC with regional involvement. This evidence leads us to recommend a comprehensive selective neck dissection of levels IIa, IIb, III, IV, and Vb in patients with lateral neck disease from PTC. The evidence for level Va is lacking, as most studies did not distinguish between levels Va and Vb, and the border between the two levels was inconsistent. Future studies will need to address these sublevels separately. © 2013, Mary Ann Liebert, Inc.

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