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IEEE General Meeting Power& Energy Society

作者： Zhijian Liu Marija D. Ilić Electrical and Computer Engineering and Engineering and Public Policy Departments Delft University of Technnology Netherlands Department of Electrical and Computer Engineering Carnegie Mellon University Pittsburgh PA USA Carnegie Mellon University Pittsburgh PA Electrical and Computer Engineering and Engineering and Public Policy Departments Delft University of Technology Delft The Netherlands

This paper is motivated by the need to automate adjustments of deviations in key output variables from their scheduled values. In particular, it is important to maintain load voltages within their pre-specified limits in response to many disturbances, for example load power factor deviations. Similarly, it is important to regulate real power line flows to within their pre-specified limits as disturbances around scheduled real power generation dispatch take place. Such automation is a feasible goal since the PMUs could provide accurate and fast sensing of key output variables of interest. Given the number of PMUs, the selection of best locations of PMUs and the control design based on these measurements becomes an engineering design problem. In this paper we provide a problem formulation for a robust Automated Voltage Control (AVC) and Automated Flow Control (AFC) design based on selecting the best locations for placing the PMUs. The AVC and AFC designs are illustrated using a small 5-bus example first. This is followed by illustrating potential performance of such design on an equivalent NPCC 36-bus system. The results indicate that the (N-1) reliability criteria can be met by combining the economic dispatch for scheduling resources given demand forecast, and by relying on an automated feedback to ensure that voltage and line flow deviations remain within the pre-specified limits in between scheduling intervals. This is done without having to know the exact location and magnitude of disturbances.

关键词： Automatic voltage control Reactive power Phasor measurement units Clustering algorithms Voltage measurement Generators

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Adaptive reliability revisited

Adaptive reliability revisited

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IEEE General Meeting Power& Energy Society

作者： Marija Ilić Electrical and Computer Engineering (ECE) and Engineering and Public Policy (EPP) Departments Carnegie Mellon University Pittsburgh PA USA

In this paper we start by recalling the seminal concepts underlying adaptive reliability of Tom Dy Liacco conceived almost four decades ago. Unfortunately, these concepts have not developed nor have been adopted by the industry yet. Recent efforts toward grid modernization will fall short of the anticipated expectations unless this gets implemented. Two distinct, yet related, challenges and opportunities are: 1) making electric energy services reliable and secure over broad ranges of conditions created by un-intended and/or intended system failures; and, 2) ensuring at the same time environmental and economic sustainability of energy services. We stress that even in the regulated industry this can be achieved only by implementing adaptive reliability. Moreover, as the industry restructures and novel resources get deployed the notions of adaptive reliability must evolve as well.

关键词： Reliability Power system reliability Industries Uncertainty Economics Risk management

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Making transmission systems smart: An opportunity which should not be missed

Making transmission systems smart: An opportunity which shou...

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IEEE General Meeting Power& Energy Society

作者： Marija Ilić Electrical and Computer Engineering (ECE) and Engineering and Public Policy (EPP) Departments Carnegie Mellon University Pittsburgh PA USA

The paper points out that while many efforts are under way to making distribution systems smart, very little serious attention has been given to rethinking the enhancements of transmission systems. Future electric energy systems are likely to require a qualitatively different management of the existing transmission system in order to enable their rapidly changing needs and objectives. The paper discusses an incremental enhancement of transmission systems in order to meet future needs. The thinking that the transmission systems already have control centers and SCADA and many analysis and decision tools misses major opportunities on the way to sustainable electric energy services of the future.

关键词： Low voltage Monitoring Decision making Sensors Particle measurements Electric potential Energy resources

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Teaching smart grids: Yet another challenge and opportunity for transforming power systems curriculum

Teaching smart grids: Yet another challenge and opportunity ...

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IEEE General Meeting Power& Energy Society

作者： Marija Ilić Electrical and Computer Engineering (ECE) and Engineering and Public Policy (EPP) Departments Carnegie Mellon University Pittsburgh PA USA

This paper concerns the challenge of teaching future energy systems using concepts familiar to engineering students. It is stressed that unless operating and design problems are formulated in a way understandable to those who do not specialize in electric power systems it becomes very difficult to identify what may be the roadblocks to innovation and better performance of the evolving energy systems. In particular, it becomes difficult to formulate problems underlying effective integration of novel resources and responsive demand by means of information technology (IT) unless these are "translated" into the frameworks understandable to those working with complex systems and to the IT designers.

关键词： Industries Education Power system dynamics Biological system modeling Smart grids Technological innovation

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Adaptive load management (ALM) in electric power systems

Adaptive load management (ALM) in electric power systems

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IEEE International Conference on Networking, Sensing and Control

作者： Jhi-Young Joo Marija D. Ilić Department of Electrical and Computer Engineering Carnegie Mellon University Pittsburgh PA USA Department of Electrical and Computer Engineering and the Department of Engineering and Public Policy Carnegie Mellon University Pittsburgh PA USA Delft University of Technnology Netherlands

ISBN: (纸本)9781424464500;9781424464531

In this work, we propose a multi-layered adaptive load management (ALM) system capable of integrating large-scale demand response in electric power systems efficiently and reliably. Electric power systems can be seen as a composition of multiple subsystems: power producers, load aggregators/utilities, end-users, etc. Focusing on the demand side of the system, we decompose the whole power system into three layers: the primary layer at the lowest level consisting of end-users of electric energy, the secondary layer or load aggregators that aggregate these endusers and provide service to them, and the tertiary level or the system/market operator at the highest level that incorporates and optimizes the objectives of the system as a whole. We pose the ALM problem as the problem of decomposing a complex network system using Lagrange decomposition techniques. Given the recent changes in electric energy systems, we propose that including more information from demand side helps improve the system-wide optimization. This is done by signaling a demand function, i.e. optimal energy use as a function of electricity price in place of a single point of a Lagrange multiplier, from the end-users at the primary layer to the higher layers. We provide a formulation of the system's decomposition problems of this multi-layered multi-directional decision making and information exchange. Our novel contribution will be showing that exchanging sensitivities of Lagrange coefficients instead of point-wise values of price data is essential for having a converging interactive information exchange within at the rate needed in physical power systems without storage. We identify open questions and plan for our future work.

关键词： Load management Power system reliability Lagrangian functions Power systems Adaptive systems Load flow control Power system economics Power generation economics Supply and demand Aggregates

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A Multi-Layered Adaptive Load Management (ALM) System: Information exchange between market participants for efficient and reliable energy use

A Multi-Layered Adaptive Load Management (ALM) System: Infor...

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IEEE PES Transmission and Distribution Conference and Exposition

作者： Jhi-Young Joo Marija D. Ilic Department of Electrical and Computer Engineering Carnegie Mellon University Department of Electrical and Computer Engineering and the Department of Engineering and Public Policy Carnegie Mellon University

ISBN: (纸本)9781424465460

In this paper, we propose a multi-layered adaptive load management (ALM) system capable of integrating large-scale demand response efficiently and reliably. At the tertiary layer, the system/market operator utilizes demand bid curves provided by the load aggregators on behalf of the end-users they serve. This information is processed by the system/market operator together with the bid curves provided by the generators. The information is further used to estimate electricity price and send it to load aggregators. Similarly, at the secondary layer, the load aggregators utilize the demand curves provided to them by the individual end-users. Based on the end-users' requests and the estimated electricity price given by the system/market operator, load aggregators create aggregate demand curves on behalf of all their users, and share them with both the system operator and their own customers. Finally, at the primary layer, individual end-users create their own demand functions while taking into consideration their own needs and preferences. They provide this information to their load aggregator. The proposed ALM system is best implemented online. In this paper, we provide a basic formulation of the multi-layered multi-directional decision making and information exchange in support of the ALM system. We illustrate this process using simple simulations. The proposed ALM can be used to implement demand response for different industry rules, such as fixed rate, time-of-use, and real-time pricing.

关键词： Demand Function Demand Response Real-Time Pricing Adaptive Load Control Adaptive Load Management

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Improving phishing countermeasures: An analysis of expert interviews

Improving phishing countermeasures: An analysis of expert in...

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2009 eCrime Researchers Summit, eCRIME '09

作者： Sheng, Steve Kumaraguru, Ponnurangam Acquisti, Alessandro Cranor, Lorrie Hong, Jason Department of Engineering and Public Policy Carnegie Mellon University Pittsburgh PA 15213 United States School of Computer Science Carnegie Mellon University Pittsburgh PA 15213 United States Heinz School of Public Policy Carnegie Mellon University Pittsburgh PA 15213 United States

ISBN: (纸本)9781424446261

In this paper, we present data from 31 semi-structured interviews with anti-phishing experts from academia, law enforcement, and industry. Our analysis led to eight key findings and 18 recommendations to improve phishing countermeasures. Our findings describe the evolving phishing threat, stakeholder incentives to devote resources to anti-phishing efforts, what stakeholders should do to most effectively address the problem, and the role of education and law enforcement. © 2009 IEEE.

关键词： computer crime

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Point/Counterpoint: Network neutrality nuances

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Communications of the ACM 2009年第2期52卷 31-37页

作者： Van Schewick, Barbara Farber, David Stanford Law School Center for Internet and Society United States Department of Law Stanford Law School United States Department of Electrical Engineering Stanford's Department of Electrical Engineering Stanford CA United States Department of Engineering and Public Policy School of Computer Science Carnegie Mellon University Pittsburgh PA United States

A comparative study in favor and against of network neutrality has been done by Barbara Van Schewick and David Farber. Barbara feels that network neutrality and its rules as Internet access means access to everything the Internet has to offer, not to access to a selection of Internet applications and content approved by the ISP. ISP have access to sophisticated technology that enables them to block applications or content one does not like, or degrade their performance by slowing the delivery of corresponding data packets. Changes in technology have given network providers an unprecedented ability to control applications and content on their network and rules will help us protect it. However, David Farber believes that the growth and expansion of Internet into all corners of society have made a major part of global life. Network providers must work together with Internet's workings to voluntarily develop better information about Internet's overall health. The capacity constraints and hurdles, and the impact of variety of applications on network capacity, and congestion problems should also be considered.

关键词： Traffic congestion

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Short term wind speed prediction by finite and infinite impulse response filters: A state space model representation using discrete markov process

Short term wind speed prediction by finite and infinite impu...

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Power Tech Conference

作者： Noha Abdel-Karim Mitchell Small Marija Ilic Engineering and Public Policy Department Carnegie Mellon University USA Carnegie Mellon University USA Electrical & Computer Engineering and Engineering & Public Policy Carnegie Mellon University USA

The importance of integrating wind power generation into electric power grids has rapidly progressed over the past decade. But the intermittency of wind power presents a special challenge for utility system operations as well as the market structure mechanisms. The problem arises from the uncertainty and variability in wind resources that causes fluctuations in the output of wind power generators. This paper presents a short-term wind speed prediction using linrealized time series model. Wind data are first collected from a weather station in ten minute resolution for a period of one year followed by a fitted two Weibull distribution parameters model being estimated from regression analysis on the logarithms of wind speed data. Transformation from Weibull into normal distribution is then held and linear predictive coefficients calculated using finite impulse response filter (FIR) and infinite impulse response filter (IRR) are evaluated for the normalized wind speed random process. Results of 10 minute ahead, one hour ahead, 12 hours ahead and 24 hours ahead wind speed predictions are presented and model accuracy in each of these time-ahead prediction scale are discussed. Also a remarkable observation of the independencies between future and historical wind speed data allows a state space representation model using discrete Markov process to best represent the stochastic behavior of wind speed signal. In doing so, optimum quantization parameters are first done for both Weibull and normal wind speed distributions and a transition probability matrices are evaluated in each case showing smooth state transition levels in wind data.

关键词： Wind speed IIR filters State-space methods Predictive models Markov processes Power system modeling Wind power generation Wind energy Finite impulse response filter Power systems

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An empirical analysis of phishing blacklists

An empirical analysis of phishing blacklists

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6th Conference on Email and Anti-Spam, CEAS 2009

作者： Sheng, Steve Wardman, Brad Warner, Gary Cranor, Lorrie Faith Hong, Jason Zhang, Chengshan Carnegie Mellon University Engineering and Public Policy Pittsburgh PA 15213 United States University of Alabama Computer Science Birmingham AL 35294 United States Carnegie Mellon University Computer Science EPP Pittsburgh PA 15213 United States Carnegie Mellon University School of Computer Science Pittsburgh PA 15213 United States Carnegie Mellon University Heinz School of Public Policy Pittsburgh PA 15213 United States

In this paper, we study the effectiveness of phishing blacklists. We used 191 fresh phish that were less than 30 minutes old to conduct two tests on eight anti-phishing toolbars. We found that 63% of the phishing campaigns in our dataset lasted less than two hours. Blacklists were ineffective when protecting users initially, as most of them caught less than 20% of phish at hour zero. We also found that blacklists were updated at different speeds, and varied in coverage, as 47% - 83% of phish appeared on blacklists 12 hours from the initial test. We found that two tools using heuristics to complement blacklists caught significantly more phish initially than those using only blacklists. However, it took a long time for phish detected by heuristics to appear on blacklists. Finally, we tested the toolbars on a set of 13,458 legitimate URLs for false positives, and did not find any instance of mislabeling for either blacklists or heuristics. We present these findings and discuss ways in which anti-phishing tools can be improved.

关键词： computer crime

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