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IEEE General Meeting Power& Energy Society

作者： Paul Hines Jay Apt Sarosh Talukdar College of Engineering University of Vermont Burlington VT USA Department of Engineering & Public Policy Carnegie Mellon University Pittsburgh PA USA Electrical and Computer Engineering Department and the Department of Engineering & Public Policy Carnegie Mellon University Pittsburgh PA USA

Despite efforts to mitigate blackout risk, the data available from the North American Electric Reliability Council (NERC) for 1984-2006 indicate that the frequency of large blackouts in the United States is not decreasing. This paper describes the data and methods used to come to this conclusion and several other patterns that appear in the data. These patterns have important implications for those who make investment and policy decisions in the electricity industry. Several example calculations show how these patterns can significantly affect the decision-making process.

关键词： Time frequency analysis Correlation Power system faults Electricity Power system protection Size measurement Probability distribution

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Model predictive dispatch in electric energy systems with intermittent resources

Model predictive dispatch in electric energy systems with in...

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IEEE International Conference on Systems, Man and Cybernetics

作者： Le Xie Marija D. Ilic Electrical and Computer Engineering Carnegie Mellon University Pittsburgh PA USA Departments of Electrical and Computer Engineering and Engineering and Public Policy Carnegie Mellon University Pittsburgh PA USA Honorary Chaired Professor for Control of Future Electricity Network Operations Faculty of Technology Policy and Management Delft University of Technnology Delft Netherlands

This paper addresses potential benefits of applying model predictive control (MPC) to solving the energy dispatch problem in electric energy systems with many intermittent renewable resources. Based on predicting the output from the intermittent resources, this paper introduces a look-ahead optimal control algorithm for dispatching the available generation with the objective of minimizing the total production cost. This method is compared with the static economic dispatch which treats intermittent resources as uncertain negative loads. We suggest that the proposed MPC approach could lower the total generation cost by directly dispatching the output from the renewable resources in order to compensate temporal load variations over pre-defined time horizons. A small 12-bus power system comprising five generators is simulated to illustrate potential benefits from a look-ahead dispatch of both intermittent and more conventional power plants. The proposed method is directly applicable to managing systems with large presence of wind and photovoltaic resources.

关键词： Predictive models Dispatching Power system simulation Photovoltaic systems Power generation Predictive control Optimal control Production Cost function Power system economics

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A Survey to Guide Group Key Protocol Development

A Survey to Guide Group Key Protocol Development

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Annual computer Security Applications Conference

作者： Ahren Studer Christina Johns Jaanus Kase Kyle O'Meara Lorrie Cranor Dept. of Electrical & Computer Engineering Carnegie Mellon University USA Carnegie Mellon University Human Computer Interaction Inst. USA Carnegie Mellon University Heinz School of Public Policy & Mgmt. Carnegie Mellon University School of Computer Science USA

A large number of papers have proposed cryptographic protocols for establishing secure group communication. These protocols allow a set of group members to exchange or establish keys to encrypt and authenticate messages within the group. At the same time, individuals outside of the group cannot eavesdrop on group communication or inject messages. There have even been usability studies, demonstrating an average user can successfully complete some of these protocols. However, group protocols are rarely used in the real world. In this work, we conduct a survey to help uncover why the general population ignores such mechanisms for group communication. We also try to determine what protocols would best match respondents' current expectations for group protocols and methods for establishing trust. Survey results indicate that a group protocol that leverages location-limited channels, PKI, or Web-of-Trust authenticated public keys and allows addition and deletion of members fulfills the majority of users' expectations.

关键词： Cryptographic protocols public key Collaborative work Internet public key cryptography computer security Application software public policy Usability Human computer interaction

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An international comparative analysis of sustainability transformation across seven universities

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International Journal of Sustainability in Higher Education 2008年第3期9卷 295-316页

作者： Ferrer-Balas, D. Adachi, J. Banas, S. Davidson, C.I. Hoshikoshi, A. Mishra, A. Motodoa, Y. Onga, M. Ostwald, M. Center for Sustainability Technical University of Catalonia Barcelona Spain Kyoto Sustainability Initiative Graduate School of Global Environmental Studies Kyoto University Kyoto Japan American Association for the Advancement of Science Center for Science Technology and Sustainability Washington DC United States Departments of Civil and Environmental Engineering and Engineering and Public Policy Carnegie Mellon University Pittsburgh PA United States Transdisciplinary Initiative for Global Sustainability (TIGS) Integrated Research System for Sustainability Science (IR3S) University of Tokyo Tokyo Japan Department of Policy Studies Faculty of Policy and Planning TERI University New Delhi India Sustainability Governance Project Creative Research Initiative Sousei Hokkaido University Hokkaido Japan Department of Civil Engineering University of Tokyo Tokyo Japan Centre for Climate Science and Policy Research Linköping University Linköping Sweden

Purpose - The purpose of this paper is to identify the key aspects of transformation of universities towards sustainability, such as the ideal characteristics of the "sustainable university", and the drivers and barriers in the transformation, by comparing the strategies of seven universities world-wide. Design/methodology/approach - A systems transformation analysis of seven case studies has been applied through a self-evaluation based on the tridimensional Framework-Level-Actors (FLA) method. Findings - The study shows that none of the three dimensions of change is predominant over the others. The main barrier to be overcome is the lack of incentive structure for promoting changes at the individual level. The main drivers for change are the presence of "connectors" with society, the existence of coordination bodies and projects, and the availability of funding, all of which are important for progress. Enhancing interdisciplinarity is a strategic objective at almost all of these universities, while transformative learning is less present. A common characteristic for most of the institutions is establishing and supporting networks of expertise within the universities. These universities show important strategic efforts and initiatives that drive and nucleate change for sustainable development, the result of a combination of drivers. Practical implications - The FLA-method has proved useful for being used at the level of comparing case-studies through a bird's-eye perspective. Originality/value - The paper demonstrates the application of a simple tool that gives a global perspective on transformational strategies used in seven cases world-wide in the search for commonalities and differences. © Emerald Group Publishing Limited.

关键词： Discipline Higher education Sustainable development Systems theory Transformational leadership

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Moisture Absorption Phenomena in Green Composite Printed Circuit Board Prototypes

Moisture Absorption Phenomena in Green Composite Printed Cir...

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Pulsed Power Conference, 2005 IEEE;San Francisco,CA,USA

作者： John D. Lincoln Andrew A. Shapiro Jean-Daniel M. Saphores Oladele A. Ogunseitan Department of Chemical Engineering and Materials Science University of California Irvine CA USA Department of Electrical Engineering and Computer Science University of California Irvine CA USA Departments of Civil and Environmental Engineering Economics and Planning Policy and Design University of California Irvine CA USA Public Health Program College of Health Sciences and the Program in Industrial Ecology Department of Environmental Health Science and Policy University of California Irvine CA USA

ISBN: (纸本)9781424422722

This research developed the moisture-resistance of printed circuit board (PCB) laminate prototypes based on the non-toxic composite materials made from epoxidized linseed oil, melamine polyphosphate, and flax fibers. One of the key issues associated with using renewable base materials in composites is their sensitivity to moisture. A characterization of the properties of the 'green' printed circuit boards developed in the present study showed that moisture absorption for untreated fiber laminates (4.87% vs. established limit <0.8% for FR4 boards over a 24 hour submersion period) compromised electrical resistance and decreased dielectric breakdown to an unacceptable level. A theoretical model was used to target methods for reducing moisture absorption. Based on this model, we found that reductions in fiber diffusivity and fiber volume fraction substantially reduce composite diffusivity. Through the use of chemical treatment, moisture absorption over a 24 hour time period was reduced from 4.87% to 1.15%, which improved electrical properties. At the end of this study, 15 of 18 PCB property requirements were met, while 3 moisture-critical property targets were narrowly missed.

关键词： Printed Circuit Board Design for Environment Green Composite Moisture Absorption Natural Fiber

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Meeting the EuP Directive: Life Cycle Assessment Information Sharing as Opportunity for Global Compliance

Meeting the EuP Directive: Life Cycle Assessment Information...

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IEEE International Symposium on Electronics and the Environment

作者： H. Scott Matthews Departments of Civil & Environmental Engineering / Engineering and Public Policy Green Design Institute Carnegie Mellon University Pittsburgh PA USA

ISBN: (纸本)142440861X

The EU's directive 2005/32/EC seeks to set eco-design standards for the life cycle of energy-using products (EuP). While not yet formally ratified like the WEEE and RoHS standards, this directive is expected to ride the same wave of momentum and go into effect in the next few years. WEEE and RoHS have gone beyond Europe and had similar application in other parts of the world, thus global EuP-like directives are also likely. If manufacturers want to continue to comply with this new wave of regulation, they will need to start exploring existing tools. A key need for compliance is the creation of global networks of shared environmental and energy profiles for products, which could be led by the electronics industry. This paper discusses developments in Life Cycle Assessment (LCA) over the last decade and how it can be a key tool in meeting EuP- like standards, currently planned to go into effect in 2007.

关键词： Manufacturing Electronic waste Europe Electronics industry Design engineering Power engineering and energy public policy Meeting planning Standards development Adders

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engineering energy services of the future by means of Dynamic Energy Control Protocols (DECPs)

Engineering energy services of the future by means of Dynami...

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IEEE International Conference on Systems, Man and Cybernetics

作者： Marija Ilic Faculty of Electrical and Computer Engineering Department and the Engineering Public Policy Department Carnegie Mellon University Pittsburgh PA USA

In this paper we conjecture that revolutionary advances in future energy services are needed and that these are only possible by means of information technology (IT). To support this claim, we first briefly describe the fundamental needs for changing the ways energy services have been provided, and possible consequences resulting from not adopting qualitatively new paradigms. We next make the case why managing energy services of the future to meet such needs will only be possible when pursuing a systematic deployment of IT-based mechanisms for processing, delivering and consuming energy. We stress open R&D questions to which basic answers are needed in order to rip benefits of IT. Notably, a multi-disciplinary approach to modeling and simulating a cyber-physical system (CPS) comprising the physical energy grids, and its support communications, sensing, and computing cyber layers is essential. Designing regulatory policies for facilitating penetration of IT at the value is also viewed as one of the key R&D challenges. Finally, we introduce our vision of an IT-framework in support of dynamic energy control protocols (DECPs) and illustrate potential benefits from implementing DECPs.

关键词： Power engineering and energy Protocols Research and development Internet telephony Photovoltaic systems Large-scale systems Information technology Energy management Stress Computational modeling

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Separability and Independence of Congestion and Reliability: Theory and Simulations

Separability and Independence of Congestion and Reliability:...

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IEEE General Meeting Power& Energy Society

作者： Seth Blumsack Marija Ilic Lester B. Lave Tepper School of Business Carnegie Mellon University Pittsburgh USA Electrical and Computer Engineering and Engineering and Public Policy Carnegie Mellon University Pittsburgh PA USA Tepper School of Business Carnegie Mellon University Pittsburgh PA USA

One policy aim under electric-industry restructuring has been to replace the centralized utility planning process (integrated resource planning) with regional planning for network investments, and decentralized decision-making for merchant investments. Through specific policies such as encouraging market-based merchant transmission and the proposed establishment of National Interest Transmission Corridors under the Energy policy Act of 2005, congestion and reliability have been treated as separable and independent system attributes. This paper brings together separate pieces of research in (S. Blumsack et al., 2006) to explore the proposition that transmission investments can be divided into those which relieve congestion and those which enhance system reliability. Using the DC power flow model with linear ATC, we derive some explicit necessary and sufficient analytical conditions under which the separability and independence assumptions hold. These include (i) the network is series-parallel; (ii) demand is completely price- inelastic; (iii) all customers value reliability identically; and (iv) the grid operator does not discriminate among customers when forced to physically ration consumption. Simulations using the IEEE 118-bus test system are presented which demonstrate the close dependence of reliability and congestion, except at very low levels of demand.

关键词： Reliability theory Niobium Investments Process planning Power system reliability Load flow Power demand Power system management Power generation economics Joining processes

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Optimizing sensor placements in water distribution systems using submodular function maximization

8th Annual Water Distribution Systems Analysis Symposium 200...

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8th Annual Water Distribution Systems Analysis Symposium 2006 2007年 109-109页

作者： Krause, Andreas Leskovec, Jure Isovitsch, Shannon Xu, Jianhua Guestrin, Carlos VanBriesen, Jeanne Small, Mitchell Fischbeck, Paul Computer Science Department Carnegie Mellon University 5000 Forbes Avenue Pittsburgh PA United States Department of Civil and Environmental Engineering Carnegie Mellon University 5000 Forbes Avenue Pittsburgh PA United States Department of Engineering and Public Policy Carnegie Mellon University 5000 Forbes Avenue Pittsburgh PA Department of Social and Decision Sciences Carnegie Mellon University 5000 Forbes Avenue Pittsburgh PA United States

Drinking water distribution networks represent complex systems. Water flow rates in a water distribution system vary with time, with periodic features that reflect temporal variations in water demand by consumers. The intentional introduction of a contaminant disrupts the system and could theoretically be detected by a sensor or network of sensors placed at nodes (pipe junctions, reservoirs, storage tanks, or even individual consumer taps) in the system. Determining the best locations for placement of these sensors represents a significant research question, because the system has multiple states, the number of possible intrusion points is large, and the likely high cost of these sensors limits the number that can realistically be deployed. The optimal placement of these sensors to minimize the effect of an introduced contaminant on the population is a critical issue. Sensor placement for intrusion detection exhibits an important diminishing returns property: adding a sensor to a sensor network improves the detection ability less than adding it to a subset of the sensor network. We prove that this submodularity property holds for the objective functions that we consider for placing sensors, and exploit it by applying algorithms for maximizing monotonic submodular functions. Unlike existing optimization algorithms for selecting sensor placements, our efficient optimization procedure has strong theoretical performance guarantees. In spite of the problem's complexity, our algorithm is guaranteed to always find a solution that is at least within 63% of the optimum, and will often find a (near-) optimal solution. This method is applied to two hypothetical distribution systems (129 nodes and 12,527 nodes) to determine optimal sensor placements for a sensor network of 5 or 20 sensors. Optimization was based on multiple criteria including: (1) minimizing time to detection, (2) minimizing population affected prior to detection, (3) minimizing expected demand for contaminated

关键词： Water distribution systems

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Toward the Value-Based Generation Investments and Utilization: Stratum Electricity Market

Toward the Value-Based Generation Investments and Utilizatio...

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Annual North-American Power Symposium

作者： Zhiyong Wu Marija Ilic Tsinghua University Beijing China Departments of Electrical and Computer Engineering and Engineering Public Policy Carnegie Mellon University USA

ISBN: (纸本)9789171785855

In this paper we model and analyze the dependence of electricity market outcomes on the market structures and rules. Market attributes such as electricity prices and their volatility, profits and revenues by the market participants and system cost are assessed. Of particular concerns are the effects of market structures on the long-term generation investments needed to meet long-term uncertain demand. The paper builds upon an earlier introduction of electricity market modeling resulting from the dynamics of fundamental market drivers, such as demand, supply and market clearing processes. This approach is employed to model and simulate the outcomes in the short- term spot markets, and compare these with the potential outcomes in a newly proposed stratum electricity market (SEM) structure comprising both spot and long-term sub-markets. The performance of the newly proposed SEM is illustrated using Monte Carlo simulations on a simple power system in which the only uncertainties come from the load forecasts and fuel prices.

关键词： Power generation Investments Electricity supply industry Uncertainty Fuels Power system modeling Power system simulation public policy Costs Load forecasting

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