The Experts below are selected from a list of 321 Experts worldwide ranked by ideXlab platform
Ziang Zhang - One of the best experts on this subject based on the ideXlab platform.
-
ISGT - Incremental Cost Consensus(ICC) and leaderless ICC implementations in FREEDM
2015 IEEE Power & Energy Society Innovative Smart Grid Technologies Conference (ISGT), 2015Co-Authors: Li Feng, Bruce M. Mcmillin, Anthony Perez Santiago, Ziang ZhangAbstract:In a smart grid, the economic dispatch problem is an optimization problem whose objective is to reduce the total generation Cost, subject to some constraints. The Incremental Cost Consensus (ICC) algorithm and Leaderless Incremental Cost Consensus (LICC) resolve the economic dispatch problem in a distributed fashion. Unlike prior work that implements ICC and LICC in simulation, in this paper, we implement ICC and LICC in a smart grid system: the Future Renewable Electric Energy Delivery and Management (FREEDM) system. In FREEDM, energy resources are managed through the Distributed Grid Intelligence (DGI), which provides coordinated control by applying distributed algorithm. Message complexity and total time of ICC and LICC in DGI are reported and shown to correspond to the simulation. ∗
-
Asynchronous distributed cooperative energy management through gossip-based Incremental Cost consensus algorithm
2013 North American Power Symposium (NAPS), 2013Co-Authors: Ziang Zhang, Navid Rahbari-asr, Mo-yuen ChowAbstract:The energy management problem in smart grid is a complex optimization problem of a Cyber-Physical System. Distributed cooperative energy management algorithms have great potential to solve this class of problems. In addition to the synchronous distributed algorithms, asynchronous distributed algorithms are more flexible, robust to packet loss and do not require global clock synchronization. In this paper, we have extended the synchronous Incremental Cost Consensus (ICC) algorithm to a gossip-based asynchronous version. The new algorithm is able to converge to the optimal solution in a distributed fashion with pairwise information exchange between neighbors without the need for any global synchronizing clock. The characteristics of the asynchronous ICC algorithm can be controlled by tuning the weighting of the updating matrix. Several case studies with different system configurations have been used to discuss the characteristics of the proposed algorithm.
-
Convergence analysis of the Incremental Cost consensus algorithm under different communication network topologies in a smart grid
IEEE Transactions on Power Systems, 2012Co-Authors: Ziang Zhang, Mo-yuen ChowAbstract:In a smart grid, effective distributed control algorithms could be embedded in distributed controllers to properly allocate electrical power among connected buses autonomously. By selecting the Incremental Cost of each generation unit as the consensus variable, the Incremental Cost consensus (ICC) algorithm is able to solve the conventional centralized economic dispatch problem in a distributed manner. The mathematical formulation of the algorithm has been presented in this paper. The results of several case studies have also been presented to show that the difference between network topologies will influence the convergence rate of the ICC algorithm.
-
The Influence of Time Delays on Decentralized Economic Dispatch by Using Incremental Cost Consensus Algorithm
Control and Optimization Methods for Electric Smart Grids, 2011Co-Authors: Ziang Zhang, Mo-yuen ChowAbstract:In a smart grid, robust energy management algorithms should have the ability to operate correctly in the presence of unreliable communication capabilities, and often in the absence of a central control mechanism. Effective distributed control algorithms could be embedded in distributed controllers to properly allocate electrical power among connected buses autonomously. By selecting the Incremental Cost of each generation unit as the consensus variable, the Incremental Cost consensus (ICC) algorithm is able to solve the conventional centralized economic dispatch problem (EDP) in a distributed manner. However, the communication time-delay may cause instability of the system and should be considered during the design process. The mathematical formulation of the ICC algorithm with time-delay is presented in this chapter. Several case studies are also presented to show the system characteristics of the ICC algorithm with time-delay.
-
the leader election criterion for decentralized economic dispatch using Incremental Cost consensus algorithm
Conference of the Industrial Electronics Society, 2011Co-Authors: Ziang Zhang, Mo-yuen ChowAbstract:In a smart grid, effective distributed control algorithms could be embedded in distributed controllers to properly allocate electrical power among connected buses autonomously. By selecting the Incremental Cost of each generation unit as the consensus variable, the Incremental Cost Consensus (ICC) algorithm is able to solve the conventional centralized economic dispatch problem in a distributed manner. The mathematical formulation of the algorithm is presented in this paper. The results of several case studies are also presented to show that the difference between network topologies will influence the convergence rate of the ICC algorithm.
Mo-yuen Chow - One of the best experts on this subject based on the ideXlab platform.
-
Asynchronous distributed cooperative energy management through gossip-based Incremental Cost consensus algorithm
2013 North American Power Symposium (NAPS), 2013Co-Authors: Ziang Zhang, Navid Rahbari-asr, Mo-yuen ChowAbstract:The energy management problem in smart grid is a complex optimization problem of a Cyber-Physical System. Distributed cooperative energy management algorithms have great potential to solve this class of problems. In addition to the synchronous distributed algorithms, asynchronous distributed algorithms are more flexible, robust to packet loss and do not require global clock synchronization. In this paper, we have extended the synchronous Incremental Cost Consensus (ICC) algorithm to a gossip-based asynchronous version. The new algorithm is able to converge to the optimal solution in a distributed fashion with pairwise information exchange between neighbors without the need for any global synchronizing clock. The characteristics of the asynchronous ICC algorithm can be controlled by tuning the weighting of the updating matrix. Several case studies with different system configurations have been used to discuss the characteristics of the proposed algorithm.
-
Convergence analysis of the Incremental Cost consensus algorithm under different communication network topologies in a smart grid
IEEE Transactions on Power Systems, 2012Co-Authors: Ziang Zhang, Mo-yuen ChowAbstract:In a smart grid, effective distributed control algorithms could be embedded in distributed controllers to properly allocate electrical power among connected buses autonomously. By selecting the Incremental Cost of each generation unit as the consensus variable, the Incremental Cost consensus (ICC) algorithm is able to solve the conventional centralized economic dispatch problem in a distributed manner. The mathematical formulation of the algorithm has been presented in this paper. The results of several case studies have also been presented to show that the difference between network topologies will influence the convergence rate of the ICC algorithm.
-
The Influence of Time Delays on Decentralized Economic Dispatch by Using Incremental Cost Consensus Algorithm
Control and Optimization Methods for Electric Smart Grids, 2011Co-Authors: Ziang Zhang, Mo-yuen ChowAbstract:In a smart grid, robust energy management algorithms should have the ability to operate correctly in the presence of unreliable communication capabilities, and often in the absence of a central control mechanism. Effective distributed control algorithms could be embedded in distributed controllers to properly allocate electrical power among connected buses autonomously. By selecting the Incremental Cost of each generation unit as the consensus variable, the Incremental Cost consensus (ICC) algorithm is able to solve the conventional centralized economic dispatch problem (EDP) in a distributed manner. However, the communication time-delay may cause instability of the system and should be considered during the design process. The mathematical formulation of the ICC algorithm with time-delay is presented in this chapter. Several case studies are also presented to show the system characteristics of the ICC algorithm with time-delay.
-
the leader election criterion for decentralized economic dispatch using Incremental Cost consensus algorithm
Conference of the Industrial Electronics Society, 2011Co-Authors: Ziang Zhang, Mo-yuen ChowAbstract:In a smart grid, effective distributed control algorithms could be embedded in distributed controllers to properly allocate electrical power among connected buses autonomously. By selecting the Incremental Cost of each generation unit as the consensus variable, the Incremental Cost Consensus (ICC) algorithm is able to solve the conventional centralized economic dispatch problem in a distributed manner. The mathematical formulation of the algorithm is presented in this paper. The results of several case studies are also presented to show that the difference between network topologies will influence the convergence rate of the ICC algorithm.
-
decentralizing the economic dispatch problem using a two level Incremental Cost consensus algorithm in a smart grid environment
North American Power Symposium, 2011Co-Authors: Ziang Zhang, Xichun Ying, Mo-yuen ChowAbstract:In a smart grid, effective distributed control algorithms could be embedded in distributed controllers to properly allocate electrical power among connected buses autonomously. By selecting the Incremental Cost of each generation unit as the consensus variable, the Incremental Cost Consensus (ICC) algorithm can solve the economic dispatch problem in a distributed manner instead of using conventional centralized approaches. In this paper, we further decrease the requirement of the communication network by using an average consensus algorithm to acquire the system power mismatch information. The mathematical formulation of the algorithms is also presented in this paper. In addition, the results of several case studies are presented to show the convergence rate of the ICC algorithm and the comparison between the previous ICC and the new two-level ICC algorithm.
D.l. Tolley - One of the best experts on this subject based on the ideXlab platform.
-
Long-Run Incremental Cost Pricing Based on Unused Capacity
IEEE Transactions on Power Systems, 2007Co-Authors: D.l. TolleyAbstract:This paper proposes a novel approach for providing long-run Incremental Cost (LRIC) pricing in network charges. The proposed approach makes use of the unused capacity of an exiting network to reflect the Cost of advancing or deferring future investment consequent upon the addition of generation or load at each study node on a distribution network. Compared with existing approaches to LRIC pricing, the proposed approach produces forward-looking charges that reflect both the extent of the network needed to service the generation or load, and the degree to which that network is utilized. The efficacy of the proposed LRIC approach has been validated by a comparison with the established investment Cost related pricing (ICRP) method used for deriving transmission charges in Great Brain (GB). This paper draws on work undertaken in projects for Western Power Distribution and Ofgem (Office of Gas and Electricity Markets, U.K.). However, the views expressed in this paper are those of the authors.
Theodore G. Ganiats - One of the best experts on this subject based on the ideXlab platform.
-
Incremental Cost-Effectiveness Analysis: The Optimal Strategy Depends on the Strategy Set
Journal of clinical epidemiology, 1999Co-Authors: Scott B. Cantor, Theodore G. GaniatsAbstract:Abstract Evaluating the Incremental Cost-effectiveness of a technology is critical to understanding the impact of its adoption. The purpose of this study was to evaluate, using a particular example, how the specific alternatives selected for a Cost-effectiveness analysis may influence the results of the analysis. In this example, we analyzed the Incremental Cost-effectiveness of estriol screening for Down syndrome. Model assumptions of expected Costs and effectiveness were based on previously published work involving four clinical strategies, including a “do nothing” (no screening) strategy. When the analysis started with all four strategies, two of the strategies could not be considered Cost- effective because of extended dominance. However, when we eliminated the “do nothing” from the strategy set because of its clinical irrelevance, all three remaining strategies might be considered Cost-effective from a policy perspective. We concluded that the Incremental Cost-effectiveness of clinical strategies could be strongly affected by the starting point for the analysis.
-
Incremental Cost‐effectiveness of incorporating oestriol evaluation in down syndrome screening programmes
Prenatal diagnosis, 1994Co-Authors: Theodore G. Ganiats, Andrea L. Halverson, Mark H. BogartAbstract:As screening for Down syndrome becomes increasingly sophisticated, it is important to evaluate the newer technologies in terms of their Cost-effectiveness. One recent addition to Down syndrome screening programmes is maternal serum unconjugated oestriol (uE3), especially when used in conjunction with maternal serum alpha-fetoprotein and human chorionic gonadotropin. Using assumptions used in a California proposal to justify an expanded screening programme for Down syndrome, we calculated both the average and the Incremental Cost-effectiveness of adding uE3. Using the base case assumptions, including an $8 fee for the uE3, the Incremental Cost-effectiveness of adding uE3 to the proposed California programme is $119,100 per case detected, a value that compares favourably with other Down syndrome screening programmes. The sensitivity analysis supports this conclusion over a wide range of assumptions. However, because of the uncertainty with some key data, it is still too early to fully support the inclusion of uE3 in Down syndrome screening programmes.
Eric A. Finkelstein - One of the best experts on this subject based on the ideXlab platform.
-
Incremental Cost effectiveness of evidence based non surgical weight loss strategies
Clinical obesity, 2019Co-Authors: Eric A. Finkelstein, Naina R. VergheseAbstract:Recent medical advancements have led to new modes of treatment for non-surgical weight loss, including several new medications. Our aim was to conduct an Incremental Cost-effectiveness analysis for all commercially available, evidence-based non-surgical weight loss interventions for people with excess weight. We identified interventions through a systematic review of randomized controlled trials that reported weight loss 12 months from baseline. We then meta-analysed the results, sourced Costs and performed an Incremental Cost-effectiveness analysis from the payer perspective. Cost-effectiveness was presented in terms of Cost per kilogram lost and quality-adjusted life years (QALY) gained. We further performed sensitivity analyses on Costs and duration of benefits, and a probabilistic sensitivity analysis. Ten interventions were identified for inclusion: six pharmaceutical products (Alli, Xenical, Qsymia, Contrave, Belviq and Saxenda), two lifestyle modification programmes (Weight Watchers Meetings and Online), one food replacement and lifestyle programme (Jenny Craig) and one intragastric balloon system (Orbera). At an Incremental Cost-effectiveness ratio of $30 071 per additional QALY gained, only Weight Watchers Meetings was Cost-effective. Sensitivity analyses revealed that for the medications to become Incrementally Cost-effective, Costs would have to decrease by as much as 91%. Results are highly dependent on duration that benefits are maintained. Despite several newly available interventions, Weight Watchers Meetings is currently the only evidence-based, commercially available, Cost-effective option for non-surgical weight loss. Other interventions, specifically medications, are more effective but priced too high to be Cost-effective.
-
Incremental Cost‐effectiveness of evidence‐based non‐surgical weight loss strategies
Clinical obesity, 2019Co-Authors: Eric A. Finkelstein, Naina R. VergheseAbstract:Recent medical advancements have led to new modes of treatment for non-surgical weight loss, including several new medications. Our aim was to conduct an Incremental Cost-effectiveness analysis for all commercially available, evidence-based non-surgical weight loss interventions for people with excess weight. We identified interventions through a systematic review of randomized controlled trials that reported weight loss 12 months from baseline. We then meta-analysed the results, sourced Costs and performed an Incremental Cost-effectiveness analysis from the payer perspective. Cost-effectiveness was presented in terms of Cost per kilogram lost and quality-adjusted life years (QALY) gained. We further performed sensitivity analyses on Costs and duration of benefits, and a probabilistic sensitivity analysis. Ten interventions were identified for inclusion: six pharmaceutical products (Alli, Xenical, Qsymia, Contrave, Belviq and Saxenda), two lifestyle modification programmes (Weight Watchers Meetings and Online), one food replacement and lifestyle programme (Jenny Craig) and one intragastric balloon system (Orbera). At an Incremental Cost-effectiveness ratio of $30 071 per additional QALY gained, only Weight Watchers Meetings was Cost-effective. Sensitivity analyses revealed that for the medications to become Incrementally Cost-effective, Costs would have to decrease by as much as 91%. Results are highly dependent on duration that benefits are maintained. Despite several newly available interventions, Weight Watchers Meetings is currently the only evidence-based, commercially available, Cost-effective option for non-surgical weight loss. Other interventions, specifically medications, are more effective but priced too high to be Cost-effective.
-
Incremental Cost-Effectiveness Analysis of Gestational Diabetes Mellitus Screening Strategies in Singapore.
Asia-Pacific journal of public health, 2015Co-Authors: Pin Yu Chen, Eric A. Finkelstein, Fabian Yap, George S. H. Yeo, Victor Samuel Rajadurai, Yap-seng Chong, Peter D. Gluckman, Seang-mei Saw, Kenneth KwekAbstract:The objective of this study was to conduct an Incremental Cost-effectiveness analysis from the payer's perspective in Singapore of 3 gestational diabetes mellitus screening strategies: universal, targeted, or no screening. A decision tree model assessed the primary outcome: Incremental Cost per quality-adjusted life year (QALY) gained. Probabilities, Costs, and utilities were derived from the literature, the Growing Up in Singapore Towards healthy Outcomes (GUSTO) birth cohort study, and the KK Women's and Children's Hospital's database. Relative to targeted screening using risk factors, universal screening generates an Incremental Cost-effectiveness ratio (ICER) of $USD10,630/QALY gained. Sensitivity analyses show that disease prevalence rates and intervention effectiveness of glycemic management have the biggest impacts on the ICERs. Based on the model and best available data, universal screening is a Cost-effective approach for reducing the complications of gestational diabetes mellitus in Singapore as compared with the targeted screening approach or no screening.
-
Incremental Cost utility analysis of deep anterior lamellar keratoplasty compared with penetrating keratoplasty for the treatment of keratoconus
American Journal of Ophthalmology, 2011Co-Authors: Eric A. Finkelstein, Jodhbir S MehtaAbstract:Purpose This study sought to determine the Cost effectiveness of deep anterior lamellar keratoplasty (DALK) compared with penetrating keratoplasty (PK) for the treatment of keratoconus. DALK is associated with lower rates of postoperative complications compared with PK, but is a more expensive procedure; whether it is Cost effective compared with PK is unknown. Design The study was an Incremental Cost-utility analysis from a health systems perspective using retrospective data on a cohort of patients with severe keratoconus. Methods The analysis was conducted using 1-year Cost and outcomes data from 148 keratoconus patients, representing 102 PK and 46 DALK cases, seen for corneal grafts between January 1991 and January 2009 at the Singapore National Eye Center. The main outcome assessed was the Incremental Cost-utility ratios associated with PK and DALK for the treatment of keratoconus. Results Over a 20-year period, PK was the lower Cost procedure and had an Incremental Cost-utility ratio of $3750 per quality-adjusted life-year compared with no surgical treatment. Compared with PK, DALK has an Incremental quality-adjusted life-year gain of 0.8 and an Incremental Cost of $2420, for an Incremental Cost-utility ratio of $3025 per quality-adjusted life-year. Conclusions Compared with PK, DALK has a favorable Cost-effectiveness ratio and, resources permitting, should be considered as a first-line treatment for keratoconus. Additional studies are needed to confirm the expected advantages of DALK over PK when it comes to long-term graft failure rates.
