6233472
Underlying technical issues in electricity deregulation
This paper reports on the results of an attempt by the Power Systems Engineering Research Center (Pserc) and EPRI to determine the technical tools missing in currently unfolding electric power restructuring scenarios. Needed tools have been divided into the functional categories of generation, transmission and distribution. In each category, there seems to be a common need to interface existing technical tools with the new economic unbundling.
33773
An Agent-Based Optimal Bidding Function
Problems such as price volatility have been observed in electric power markets. Demand-side participation is often offered as a potential solution by promising to increase market efficiency when hockey-stick type offer curves are present. However, individual end-consumer will surely value electricity differently, which makes demand-side participation as a group and at a bus difficult. In this paper demand is categorized into two groups: one that highly values reliability and the other that does not. The two types are modeled separately and a new optimal bidding function is developed and tested based on this model.
10032152
Parallel processing implementation of the unit commitment problem with full AC power flow constraints
The authors describe a parallel implementation of the Lagrangian Relaxation Algorithm with variable duplication for the thermal unit commitment problem. The formulation was previously reported by the authors and allows inclusion of the full nonlinear AC network power flow model, which permits addressing voltage limits, as well as more realistic branch flow limits than is possible with a linear DC flow model. Thus, potential VAr production can be used as another criterion for commitment of otherwise expensive generators in strategic locations. The algorithm is highly parallelizable, and the authors have taken advantage of this in a version currently being developed for the Cornell Theory Center's Velocity AC3 NT cluster.
6798576
Locational pricing and scheduling for an integrated energy-reserve market
It is well known that given a network that can become constrained on voltage or real power flows, reserves must also be spatially located in order to handle all credible contingencies. However, to date, there is no credible science-based method for assigning and pricing reserves in this way. Presented in this paper is a new scheduling algorithm incorporating constraints imposed by grid security considerations, which include one base case (intact system) and a list of possible contingencies (line-out, unit-lost, and load-growth) of the system. By following a cost-minimizing co-optimization procedure, both power and reserve are allocated spatially for the combined energy and reserve markets. With the Lagrange multipliers (dual variables) obtained, the scheduling algorithm also reveals the locational shadow prices for the reserve and energy requirements. Unlike other pricing and scheduling methods in use, which are usually ad-hoc and are based on engineering judgment and experience, this proposed formulation is likely to perform better in restructured markets when market power is a potential problem. An illustrative example of a modified IEEE 30-bus system is used to introduce concepts and present results.
37344904
Power System Bidding Tournaments for a Deregulated Environment
In this paper we describe certain tools for understanding and operating power systems in a deregulated environment. Many of the current models for this competitive market that employ an independent system operator (ISO) for controlling transmission, ensuring fair access and security, and providing a spot market for power will be studied. This centrally-dispatched power pool also ensures that generation meets demand based on bids submitted daily from independent generators (and from customers offering interruptible loads). Currently, most I S 0 bidding models allow only a single bid per day. In this paper, we present an asynchronous bidding scheme as a possible alternative. In particular, we examine the effects of including a feedback mechanism such that upon receiving generation levels from the ISO, independent generators (IGs) be allowed to modify their bid if they so desire. This competitive or ‘sequential’ bidding process should be allowed to take place each day for a predetermined period of time; in this way, IGs will have a chance to compete and hopefully optimize their profit margins. This paper also discusses the development tools necessary for examining the effects of different bidding processes on the I S 0 model and evaluating their capability of driving the market to an efJicient state of operation.
14857147
An economic analysis of the self commitment of thermal units
Given the load profile of an electricity market and the capabilities of the set of generators supplying power to that market, it is likely that at any given point in time, available supply will exceed demand. If only a subset of generators is required, some method is required to commit and de-commit generators. In the past, system operators have employed a centralized method of unit commitment. Deregulation of the electricity industry throws doubt on the continued suitability of this method due to fairness issues and availability of accurate cost data. This paper examines the performance of decentralized unit commitment, where dispatch of generators is determined by offer curves submitted into a spot market by power producers.
31462634
Kuratowski Chains
9403384
A pilot study of teaching the strategic use of common computer applications
Many users do not progress from a basic use of computer applications to more efficient usage. A strategic approach to training that focuses on teaching efficient strategies in addition to commands was successfully developed by Bhavnani and John at Carnegie Mellon University. A controlled experiment comparing this method of teaching to traditional command-based instruction was performed at the University of Western Australia. We found the teaching method is transferable to the Australian context and it appears to be remarkably robust in terms of delivery, student prior experience levels and motivation. The results clearly indicate that students can be taught to use common computer applications more efficiently than they would otherwise achieve.
2021116
Industry experience in migrating to object technology
Object oriented software engineering (OOSE) is becoming a common approach to software development. As third generation OOSE processes are established (e.g. OPEN (I. Graham, 1997) and the Unified Software Development Process (I. Jacobson, 1999)) organisations will start to consider OOSE as a mature technology. This recognition will mean that more organisations will go through the process of changing their current software development processes. The paper reports on the experience of one team at a large technical firm as they adopted OOSE processes for a major project. The experience of this team confirms most of what has been previously reported in the literature, and adds two additional observations. The first observation is that other literature in this field does not consider team motivation as a factor that contributes to migration success. The second observation is that other literature does not consider the relative impact of some factors over other factors.
6336074
Developing Case Studies to Enhance Student Learning
In this paper we describe the cases developed in response to the multifaceted challenges we faced in educating IT professionals in intermediate-level programming. The challenges included: the practical nature of the subject, the level of skill attained, preparing students for the workplace and class size. We implemented Problem-Based Learning (PBL) as the teaching and learning method to meet these challenges by helping first-year university students learn programming while simultaneously developing graduate capabilities. This necessitated redevelopment of the curriculum and the way it was taught. We combined software engineering and information systems approaches in real-world scenarios. The cases were designed to help students come to terms with the human side of information technology through the context and method of teaching and learning as they worked through the cases.
1883056
An Investigation into Keystroke Latency Metrics as an Indicator of Programming Performance
Typing has long been studied in psychology and HCI, and strong cognitive models for transcription typing exist. The goal of the present research was to test if there is any correlation between students' keystroking speed and performance while they are programming. We present the results from two studies with computer science students conducted in different contexts. Keystroke timings were recorded while they worked on Java and Ada source code. Quality of their programming work was measured mainly in terms of completeness. In the controlled experiment that lasted six hours, 39 students undertook three change tasks on a 6000 LOC Java application. In the field study, data was collected over 6 weeks from 141 students while they worked unsupervised on Ada programming in first year laboratories. In both cases there were highly significant (P=0.001), moderately strong, negative correlations between speed and coding performance. With additional development, these techniques may have promise for user modelling and assessment as well as in educational diagnostics.