The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Malgorzata Mareksadowska - One of the best experts on this subject based on the ideXlab platform.
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on chip power Supply Network optimization using multigrid based technique
Design Automation Conference, 2003Co-Authors: Kai Wang, Malgorzata MareksadowskaAbstract:In this paper, we present a novel multigrid-based technique for on-chip power Supply Network optimization. We reduce a large-scale Network to a much coarser one which can be efficiently optimized. The solution for the original Network is then quickly computed using a back-mapping process. We model the power grid by an RLC Network and use time-varying current sources to capture the on-chip switching. Our technique is capable of optimizing power grid and decoupling capacitance simultaneously. Experimental results show that the proposed technique provides more robust and area-efficient solutions than those obtained by the earlier approaches. It also provides a significant speed-up and brings up a possibility of incorporating power Supply Network optimization into other physical design stages such as signal routing.
John Yen - One of the best experts on this subject based on the ideXlab platform.
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analyzing the resilience of complex Supply Network topologies against random and targeted disruptions
IEEE Systems Journal, 2011Co-Authors: Kang Zhao, Akhil Kumar, Terry P Harrison, John YenAbstract:In this paper, we study the resilience of Supply Networks against disruptions and provide insights to Supply chain managers on how to construct a resilient Supply Network from the perspective of complex Network topologies. Our goal is to study how different Network topologies, which are created from different growth models, affect the Network's resilience against both random and targeted disruptions. Of particular interest are situations where the type of disruption is unknown. Using a military logistic Network as a case study, we propose new Network resilience metrics that reflect the heterogeneous roles (e.g., Supply, relay, and demand) of nodes in Supply Networks. We also present a hybrid and tunable Network growth model called Degree and Locality-based Attachment (DLA), in which new nodes make connections based on both degree and locality. Using computer simulations, we compare the resilience of several Supply Network topologies that are generated with different growth models. The results show that the new resilience metrics can capture important resilience requirements for Supply Networks very well. We also found that the Supply Network topology generated by the DLA model provides balanced resilience against both random and targeted disruptions.
Kai Wang - One of the best experts on this subject based on the ideXlab platform.
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On-chip power-Supply Network optimization using multigrid-based technique
IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems, 2005Co-Authors: Kai Wang, M. Marek-sadowskaAbstract:In this paper, we present a novel multigrid-based technique for the problem of on-chip power-Supply Network optimization. The multigrid-based technique is applied to reduce a large-scale Network to a much coarser one. The reduced Network can be efficiently optimized. The solution for the original Network is then quickly computed using a back-mapping process. Due to the adoption of an accurate resistance-inductance-capacitance power-Supply Network and time-varying switching-current model, our technique is capable of optimizing power grid and decoupling capacitance simultaneously. Experimental results show that large-scale power-Supply Networks with millions of nodes can be solved in a few minutes. The proposed technique not only speeds up significantly the optimization process, without compromising the quality of solutions, but also brings up a possibility of incorporating the power-Supply Network optimization into other physical design stages such as signal routing.
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on chip power Supply Network optimization using multigrid based technique
Design Automation Conference, 2003Co-Authors: Kai Wang, Malgorzata MareksadowskaAbstract:In this paper, we present a novel multigrid-based technique for on-chip power Supply Network optimization. We reduce a large-scale Network to a much coarser one which can be efficiently optimized. The solution for the original Network is then quickly computed using a back-mapping process. We model the power grid by an RLC Network and use time-varying current sources to capture the on-chip switching. Our technique is capable of optimizing power grid and decoupling capacitance simultaneously. Experimental results show that the proposed technique provides more robust and area-efficient solutions than those obtained by the earlier approaches. It also provides a significant speed-up and brings up a possibility of incorporating power Supply Network optimization into other physical design stages such as signal routing.
Anders Levermann - One of the best experts on this subject based on the ideXlab platform.
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modeling loss propagation in the global Supply Network the dynamic agent based model acclimate
Journal of Economic Dynamics and Control, 2017Co-Authors: Christian Otto, Sven N Willner, Leonie Wenz, Katja Frieler, Anders LevermannAbstract:World markets are highly interlinked and local economies extensively rely on global Supply and value chains. Consequently, local production disruptions, for instance caused by extreme weather events, are likely to induce indirect losses along Supply chains with potentially global repercussions. These complex loss dynamics represent a challenge for comprehensive disaster risk assessments. Here, we introduce the numerical agent-based model acclimate designed to analyze the cascading of economic losses in the global Supply Network. Using national sectors as agents, we apply the model to study the global propagation of losses induced by stylized disasters. We find that indirect losses can become comparable in size to direct ones, but can be efficiently mitigated by warehousing and idle capacities. Consequently, a comprehensive risk assessment cannot focus solely on first-tier suppliers, but has to take the whole Supply chain into account. To render the Supply Network climate-proof, national adaptation policies have to be complemented by international adaptation efforts. In that regard, our model can be employed to assess reasonable leverage points and to identify dynamic bottlenecks inaccessible to static analyses.
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acclimate a model for economic damage propagation part ii a dynamic formulation of the backward effects of disaster induced production failures in the global Supply Network
Environment Systems and Decisions, 2014Co-Authors: Sven N Willner, Leonie Wenz, Anders Levermann, Robert BierkandtAbstract:As global warming accelerates extreme weather events such as floods, droughts and storms are likely to increase in intensity and frequency. With regard to a highly globalized world economy built on complex Supply and value-added chains, this trend will challenge societies locally and globally. Regional production disruptions might induce shock waves that propagate through the global Supply Network and evoke supra-regional shortages. While such cascading effects are promoted by forward linkages in the global economic Network, the demand-induced backward dynamics respond in a more complex way. On the one hand, backward linkages may additionally spread economic losses and thus aggravate the disaster aftermath. On the other hand, the readdressing of demand enables a readjustment of production, which may weaken or even dissipate shock waves. Here, we analyze the backward effects of disaster-induced production breakdowns by complementing the numerical damage transfer model Acclimate by a demand side. Based on model simulations, we show that the possibility of production extension and demand readdressing may be crucial for mitigating economic losses in the course of an extreme event.
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acclimate a model for economic damage propagation part 1 basic formulation of damage transfer within a global Supply Network and damage conserving dynamics
Environment Systems and Decisions, 2014Co-Authors: Leonie Wenz, Anders Levermann, Robert Bierkandt, Sven WillnerAbstract:Climate extremes are expected to become more frequent and intense under future warming. In a globalized economy, outages of productive capital and infrastructure have the potential to spread around the world. In order to address those repercussions in the framework of a risk analysis or a resilience strategy, a disaster’s indirect consequences on the economic Supply Network need to be understood. We developed a numerical model to simulate these indirect effects along global Supply chains for time scales of days to months. This article is the first in a series of four, which describes the damage-propagation model. In this first paper, we describe the pure damage propagation within the Network and focus on the fundamental propagation of Supply failure between production sites including their input and output storages and transport-related time delay. Idealized examples are presented to illustrate the dynamic damage propagation. Further articles will extend the dynamics to include demand changes due to the perturbation in the Supply, the possibility to extend production to compensate for production failure, price responses and adaptive changes in the economic Supply Network. The underlying global Supply Network is based on data from multi-regional input–output tables. Transportation times are derived from geographic distances. In the initial model version presented here, indirect production losses are caused by cascading effects. They are propagated within the Network without significant reduction in loss (damage conservation). They can thus be observed within the different storages or they “leak out” of the system through reduced consumption of the final consumer. As an example, we investigate the cascading behavior of losses for the machinery sector in Japan.
Federico Caniato - One of the best experts on this subject based on the ideXlab platform.
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production and Supply Network strategies within the fashion industry
International Journal of Production Economics, 2015Co-Authors: Laura Macchion, Pamela Danese, Antonella Moretto, Federico Caniato, Maria Caridi, Andrea VinelliAbstract:Decisions on where and how to locate a production and Supply Network have become an increasingly important part of a firm’s global Supply Network strategy and are critical to obtain competitive advantages. This paper contributes to extend knowledge in the field of production and Supply Network strategy in the fashion industry. Analysing the Supply Network strategy literature, the paper investigates production and Supply Network configurations that fashion-industry firms implement to remain competitive in a global context. Statistical analyses on survey data from 132 Italian fashion companies highlight the existence of three different clusters of companies that have identified alternative ways to organise their production and Supply Networks that are aligned with their specific competitive priorities (e.g., critical success factors). The study characterises the three different clusters of production and Supply strategies of fashion companies, and provides useful interpretation of differences among clusters. In particular, the research distinguishes which subset of managerial capabilities (e.g., ability to trace Supply Network processes, collaborate along the chain and realize production, prototypes and samples in local Networks linking brand reputation to Made-in-Italy,) fashion companies should possess and nurture to successfully develop and implement different, either local or international, production and Supply Network configurations.
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building a secure and resilient Supply Network
Supply Chain Management Review, 2003Co-Authors: James B Rice, Federico CaniatoAbstract:SUBTITLE: FOR MANY COMPANIES, THE ONLY THING STANDING BETWEEN THEM AND A DISASTROUS Supply CHAIN DISRUPTION IS LUCK. BUT, AS ANY GAMBLER KNOWS, YOUR LUCK EVENTUALLY RUNS OUT. IN TODAY'S BUSINESS ENVIRONMENT, YOU NEED A Supply Network THAT HAS COMPREHENSIVE SECURITY PROCESSES AND PROCEDURES IN PLACE AND IS RESILIENT ENOUGH TO BOUNCE BACK FROM ANY DISRUPTIONS THAT DO HAPPEN. LUCK PLAYS NO PART IN THE EQUATION.
