Split-and-Merge Method for Accelerating Convergence of Stochastic Linear Programs

Abstract: Stochastic program optimizations are computationally very expensive, especially when the number of scenar-ios are large. Complexity of the focal application, and the slow convergence rate add to its computational complexity. We propose a split-and-merge (SAM) method for accelerating the convergence of stochastic lin-ear programs. SAM splits the original problem into subproblems, and utilizes the dual constraints from the subproblems to accelerate the convergence of the original problem. Our initial results are very encouraging, giving up to 58 % reduction in the optimization time. In this paper we discuss the initial results, the ongoing and the future work.

Product assignment in flexible multilines : Part 2 - Single-state systems with no demand splitting / 1993:107

Includes bibliographical references (p. 34)

Energy-efficient computing for HPC workloads on heterogeneous manycore chips

Power and energy efficiency is one of the major challenges to achieve exascale computing in the next several years. While chips operating at low voltages have been studied to be highly energy-efficient, low voltage operations lead to heterogeneity across cores within the microprocessor chip. In this work, we study chips with low voltage operation and discuss programming systems, and performance modeling in the presence of heterogeneity. We propose an integer linear programming based approach for selecting optimal configu-ration of a chip that minimizes its energy consumption. We obtain an average of 26 % and 10.7 % savings in energy con-sumption of the chip for two HPC mini-applications- min-iMD and Jacobi, respectively. We also evaluate the energy savings with execution time constraints, using the proposed approach. These energy savings are significantly more than the savings by sub-optimal configurations obtained from heuristics

Product assignment in flexible multi-lines : the case of single stage with demand splitting

Includes bibliographical references (p.19-20)

Molecularly Targeted Nanoparticles for Modulation of Inflammatory Mediators in Atherosclerosis

The enzyme thrombin has been demonstrated through experimental and clinical studies to play a crucial role in mediating both inflammation and thrombosis in atherosclerosis. The cellular effects of thrombin in promoting atherosclerosis involve the activation of signaling pathways that result in the secretion of a host of various chemokines, cytokines, cell adhesion molecules, etc. that promote vascular inflammation. Due in part to thrombin and other pro-atherogenic molecules, this prolonged inflammatory state in atherosclerosis results in the deterioration of the endothelium, increasing the risk of focal thrombosis. Current treatment strategies to address the role of thrombin in atherosclerosis, despite efficacy of anticoagulant activity, suffer from significant bleeding side effects. Thus, the goal of this dissertation was to address the central role that thrombin plays in atherosclerosis and thrombosis through the application of perfluorocarbon nanoparticles carrying the direct thrombin inhibitor D-phenylalanyl-L-prolyl-L-arginyl chloromethylketone, to impart focal anti-inflammatory and anticoagulant effects at sites of high thrombin activity. In this work, we demonstrate the ability of thrombin-inhibiting nanoparticles and liposomes to form localized anticlotting surfaces that inhibit the growth of clots both in vivo and on ex vivo applications on bare metal vascular stents. We also investigate the use of quantitative fluorine magnetic resonance spectroscopy (19F-MRS) to demonstrate an inverse relationship between endothelial barrier integrity and propensity for thrombosis. We show that increased exposure of an atherosclerotic animal to an inflammatory stimulus (e.g. cholesterol) over time decreases endothelial barrier integrity and increases hypercoagulability, however resolution of these symptoms after removal of the inflammatory stimulus can be tracked using 19F-MRS. Furthermore, we demonstrate through proof-of-concept imaging studies, the possibility for non-invasive imaging of endothelial barrier disrupted atherosclerotic plaques. These concepts in mind, our final objective was to utilize the ability to deliver localized thrombin inhibition with thrombin-inhibiting nanoparticles and demonstrate their ability to limit the effect of vascular inflammation on loss of endothelial barrier integrity, as measured by 19F-MRS. Our results indicate that within one month of treatment with thrombin-inhibiting nanoparticles, ApoE-null atherosclerotic mice presented with diminished endothelial barrier loss, reduced hypercoagulability, and an overall 22.5% decrease in aortic arch plaque deposition. Future work on this platform would involve the improvement of dosing regimens that may address earlier time points of atherosclerosis development that may have a greater effect on induction of vascular inflammation. Nevertheless, these results demonstrate for the first time, the utility of focal thrombin inhibition as a means for a limiting vascular inflammation and hypercoagulability in atherosclerosis

Product assignment in flexible multilines : Part 1 - Single-state systems with demand splitting / 1993:106

Includes bibliographical references (p. 21-22)

Supply chain efficiency and security: Coordination for collaborative investment in technology

Despite the potential value of information technologies for supply chain management, they are not always adopted as expected. We examine coordination problems and corresponding incentive mechanisms between a manufacturer and a retailer for jointly investing in a new technology that has the potential to improve the efficiency and security of the supply chain. We show that depending on the relative strength of the efficiency and security concerns, supply chain stakeholders in a decentralized supply chain face two different coordination problems in investing in the new technology: (1) when security concerns are not strong enough to dominate efficiency concerns, stakeholders may not have a sufficient incentive to invest; therefore, at least one stakeholder under invests. Our analysis shows that internal incentive mechanisms, such as investment cost sharing between stakeholders, are not likely to resolve this underinvestment; instead, external financial incentive mechanisms, such as tax incentives, need to be considered. (2) When security concerns are strong enough to dominate efficiency concerns, stakeholders may not invest at all because of the uncertainty of other stakeholders' behavior, rather than the lack of an incentive to invest in the technology. Our analysis shows that external interventions, such as imposing a penalty for a breach of security, can be used as a way of reducing such behavioral uncertainty.Supply chain management Collaborative investment in technology Supply chain efficiency Supply chain security