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In this paper, we consider convex feasibility problems (CFPs) where the underlying sets are loosely coupled, and we propose several algorithms to solve such problems in a distributed manner. These algorithms are obtained by applyi...
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In this paper, we consider convex feasibility problems (CFPs) where the underlying sets are loosely coupled, and we propose several algorithms to solve such problems in a distributed manner. These algorithms are obtained by applying proximal splitting methods to convex minimization reformulations of CFPs. We also put forth distributed convergence tests which enable us to establish feasibility or infeasibility of the problem distributedly, and we provide convergence rate results. Under the assumption that the problem is feasible and boundedly linearly regular, these convergence results are given in terms of the distance of the iterates to the feasible set, which are similar to those of classical projection methods. In case the feasibility problem is infeasible, we provide convergence rate results that concern the convergence of certain error bounds.
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This paper addresses the stability of a newly-developed control strategy for networked control systems (NCS). This control strategy hones the potential of constrained model predictive control (MPC) by buffering the predicted contr...
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This paper addresses the stability of a newly-developed control strategy for networked control systems (NCS). This control strategy hones the potential of constrained model predictive control (MPC) by buffering the predicted control sequence at the actuator in anticipation of typical data transmission errors associated with NCS. Closed-loop stability in the sense of Lyapunov is guaranteed for the controller in the linear case, by bounding the projected receding horizon costs by lower-and upper-bounding terms using a predetermined terminal cost. A stability theorem is developed, which provides a suboptimal measure for the controller in real time, and is sufficient to estimate the worst-case transmission delay that can be handled by the developed control buffering strategy. The stability conditions, as governed by the theorem, are validated through real-time implementation on an electro-hydraulic servo system of an industrial processing machine, through an Ethernet network.
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OBJECTIVE To assess the use of intraoperative IV ketorolac (Toradol) on the peri-operative total morphine milligram equivalent (MME) requirements of patients undergoing ureteroscopy for nephrolithiasis. METHODS Patients undergoing...
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OBJECTIVE To assess the use of intraoperative IV ketorolac (Toradol) on the peri-operative total morphine milligram equivalent (MME) requirements of patients undergoing ureteroscopy for nephrolithiasis. METHODS Patients undergoing ambulatory ureteroscopy for nephrolithiasis were randomized to receive ketorolac at time of anesthesia induction. Patients and surgeons were blinded to treatment. Intraoperative, postoperative and combined MME were calculated. Multivariable regression was used to identify independent predictors of MME requirement. Complications were recorded. RESULTS A total of 94 patients were analyzed following randomization. There were 46 patients in the treatment arm and 48 patients in the control arm. There were no statistically significant differences in gender, age, BMI, operative length or baseline pain medication use between groups (P >.05). Patients in the treatment arm required lower intraoperative MME when compared to the control arm (17.1 vs 24, P< .01). There were no statistically significant differences in the postoperative MME requirements between groups. The combined pen-operative MME was lower in the treatment arm compared to the control arm (22.2 vs 30.4, P< .02). Ketorolac use was an independent predictor of lower MME use on multivariable analysis (beta coefficient -5.1, P< .01). There was no statistically significant difference with regards to complication numbers between the treatment arms. CONCLUSION Ketorolac during ureteroscopy is associated with a 37% reduction in narcotic requirement and is an independent predictor of decreased pen-operative narcotic needs. These findings show that intra-operative use of ketorolac effectively reduces narcotic requirements and should be considered independently or as part of a multimodal pain control protocol, unless otherwise contraindicated. (C) 2022 Elsevier Inc.
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Feasibility analysis is a useful technique for evaluating the operability and ultimately the flexibility of chemical processes. However, it is difficult to solve the feasibility test problem for process models involving black-box ...
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Feasibility analysis is a useful technique for evaluating the operability and ultimately the flexibility of chemical processes. However, it is difficult to solve the feasibility test problem for process models involving black-box constraints. This issue can be addressed through the use of surrogate-based methods for feasibility analysis. These techniques rely on the creation of a reduced-order model that approximates the feasibility function for a process. The feasible region for the process can then be evaluated based on the surrogate model. In this work, a novel method for surrogate-based feasibility analysis based on kriging metamodels will be presented. This algorithm differs from previously published approaches in the way that the expected improvement function is evaluated. In addition, the proposed method explicitly considers surrogate model prediction uncertainty. The algorithm is also extended to problems of dynamic feasibility analysis, where the shape and size of the feasible region may change with time. A series of test problems will be used to demonstrate the surrogate-based feasibility algorithm, including those with nonconvex and disjoint feasible regions. Finally, the algorithm will be used to evaluate the feasible region for a dynamic roller compaction process. (C) 2015 Elsevier Ltd. All rights reserved.
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Japanese knotweed (Polygonum cuspidatum) is one ofan increasing number of undesirable, invasive plantsestablished along roads and stream banks in the Catskillregion of New York. Besides being fairly resistant to her-bicides (Cronk...
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Japanese knotweed (Polygonum cuspidatum) is one ofan increasing number of undesirable, invasive plantsestablished along roads and stream banks in the Catskillregion of New York. Besides being fairly resistant to her-bicides (Cronk and Fuller 1995), it often grows alongstream banks, where many herbicides commonly avail-able to homeowners cannot safely or legally be applied.For these reasons, mechanical control is often a preferredmanagement technique. Because herbaceous wastes arenot allowed at the solid waste management center forDelaware County, mechanically cut or pulled live plantparts are sometimes piled in aboveground bins to dry andthen burned in place. However, since open burning is notallowed in many locations, an alternative method to safelydispose of live plant parts is needed.
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The design and optimization of reactive distillation columns using feasibility analysis is addressed.Based on the feasible regions identified in previous work,we present two examples to illustrate the benefits of having feasibilit...
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The design and optimization of reactive distillation columns using feasibility analysis is addressed.Based on the feasible regions identified in previous work,we present two examples to illustrate the benefits of having feasibility information when locating design alternatives for systems with ideal vapor-liquid equilibrium.The examples include a reactive column for the metathesis of 2-pentene and a multifeed reactive column with a constant volatility mixture.In the first example,we use the feasible regions to initialize an optimization-based design strategy.For the second example,we characterize the feasible regions to determine feasible placement strategies for side streams and reactive stages.The design insights gained from feasibility analysis are highlighted for each example.
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