Optimization based bidding strategies in the deregulated market

With the deregulation of electric power systems, market participants are facing an important task of bidding energy to an independent system operator (ISO). This paper presents a model and a method for optimization-based bidding and self-scheduling where a utility bids part of its energy and self-schedules the rest as in New England. The model considers ISO bid selections and uncertain bidding information of other market participants. With appropriately simplified bidding and ISO models, closed-form ISO solutions are first obtained. These solutions are then plugged into the utility's bidding and self-scheduling model which is solved by using Lagrangian relaxation. Testing results show that the method effectively solves the problem with reasonable amount of CPU time     

Copon法与MUSIC法求解七单元线形天线波阵达方向比较研究

基于Copon法与MUSIC法求解七单元线形天线波阵达方向,数值计算得到在π6、2π3、5π6和π3处都有尖锐的方向图线,并且MUSIC法作出的波达方向估计(极坐标和直角坐标)响应的幅度更大一些。改变四个方向入射频率值的大小,发现波阵达方向响应幅度变化不大。研究研究结论天线器件设计提供理论依据。     

A rational surgical approach for intra-thoracic esophageal perforation

The surgical experiences of intrathoracic esophageal perforation in 17 consecutive cases seen during the last eight years are reviewed. Using a rational approach to this critical condition, the mortality and morbidity rates were lower than before. For acute perforation in a corrosive-injured esophagus, subtotal esophagectomy by eversion stripping was an effective procedure for life saving. For acute perforation of a normal or chronic fibrotic but functional esophagus, early primary repair was usually successful for healing. For chronic esophageal perforation, usually complicated by mediastinal abscess or purulent pleural effusion, an adequate local drainage or supplemented with a newly designed, temporary diversion procedure for drainage of saliva and gastric acid was recommended.     

Articular cartilage in the knee: mapping of the physiologic parameters at MR imaging with a local gradient coil--preliminary results

The authors designed and constructed a local gradient coil that produces large gradients and short rise times and connects to their clinical system. In a cadaveric patellar cartilage specimen, the coil was used to acquire images of the physiologic parameters T1, T2, proton density, and apparent diffusion coefficient. Variations in these parameters were evident in regions of normal and abnormal cartilage.     

Energy clearing price prediction and confidence interval estimation with cascaded neural networks

The energy market clearing prices (MCPs) in deregulated power markets are volatile. Good MCP prediction and its confidence interval estimation will help utilities and independent power producers submit effective bids with low risks. MCP prediction, however, is difficult since bidding strategies used by participants are complicated and various uncertainties interact in an intricate way. Furthermore, MCP predictors usually have a cascaded structure, as several key input factors need to be predicted first. Cascaded structures are widely used, however, they have not been adequately investigated. This paper analyzes the uncertainties involved in a cascaded neural-network (NN) structure for MCP prediction, and develops the prediction distribution under the Bayesian framework. A computationally efficient algorithm to evaluate the confidence intervals by using the memoryless Quasi-Newton method is also developed. Testing results on a classroom problem and on New England MCP prediction show that the method is computationally efficient and provides accurate prediction and confidence coverage. The scheme is generic, and can be applied to various networks, such as multilayer perceptrons and radial basis function networks.     

Scheduling parallel operations in automation for minimum execution time based on pert

The use of parallel operations in automation, such as part fabrication and assembly, computation and control of industrial robots, etc., may yield a minimum production time and thereby increase productivity. However, the coupling between consecutive phases of operations results in series-parallel precedence constraints that may create unavoidable idle time intervals during the operations. To solve the problem, idle time intervals must be broken down and reduced. An algorithm that determines a minimum time-ordered schedule for the parallel operaitons is developed based on the Program Evaluation and Review Technique using the method of “variable” branch and bound.     

High quality interpoly-oxynitride grown by NH3nitridation and N2O RTA treatment

In this letter, a method to grow high quality interpolysilicon-oxynitride (interpoly-oxynitride) film is proposed. Samples, nitridized by NH₃ with additional N₂O annealing and CVD TEOS deposited on poly-oxynitride (poly-I) with RTA N ₂O oxidation, show excellent electrical properties in terms of very high electric breakdown field, low leakage current, high charge to breakdown, and low electron trapping rate. This novel film is a good candidate for an interpoly dielectric of future high density EEPROM and flash memory devices