Machine Learning is the study of methods for programming computers to learn. Computers are applied to a wide range of tasks, and for most of these it is relatively easy for programmers to design and implement the necessary software. However, there are many tasks for which this is difficult or impossible. These can be divided into four general categories. First, there are problems for which there exist no human experts. For example, in modern automated manufacturing facilities, there is a need to predict machine failures before they occur by analyzing sensor readings. Because the machines are new, there are no human experts who can be interviewed by a programmer to provide the knowledge necessary to build a computer system. A machine learning system can study recorded data and subsequent machine failures and learn prediction rules. Second, there are problems where human experts exist, but where they are unable to explain their expertise. This is the case in many perceptual tasks, such as speech recognition, hand-writing recognition, and natural language understanding. Virtually all humans exhibit expert-level abilities on these tasks, but none of them can describe the detailed steps that they follow as they perform them. Fortunately, humans can provide machines with examples of the inputs and correct outputs for these tasks, so machine learning algorithms can learn to map the inputs to the outputs. Third, there are problems where phenomena are changing rapidly. In finance, for example, people would like to predict the future behavior of the stock market, of consumer purchases, or of exchange rates. These behaviors change frequently, so that even if a programmer could construct a good predictive computer program, it would need to be rewritten frequently. A learning program can relieve the programmer of this burden by constantly modifying and tuning a set of learned prediction rules. Fourth, there are applications that need to be customized for each computer user separately. Consider, for example, a program to filter unwanted electronic mail messages. Different users will need different filters. It is unreasonable to expect each user to program his or her own rules, and it is infeasible to provide every user with a software engineer to keep the rules up-to-date. A machine learning system can learn which mail messages the user rejects and maintain the filtering rules automatically. Machine learning addresses many of the same research questions as the fields of statistics, data mining, and psychology, but with differences of emphasis. Statistics focuses on understanding the phenomena that have generated the data, often with the goal of testing different hypotheses about those phenomena. Data mining seeks to find patterns in the data that are understandable by people. Psychological studies of human learning aspire to understand the mechanisms underlying the various learning behaviors exhibited by people (concept learning, skill acquisition, strategy change, etc.).

Machine learning

The Compact Muon Solenoid (CMS) detector is described. The detector operates at the Large Hadron Collider (LHC) at CERN. It was conceived to study proton-proton (and lead-lead) collisions at a centre-of-mass energy of 14 TeV (5.5 TeV nucleon-nucleon) and at luminosities up to 10(34)cm(-2)s(-1) (10(27)cm(-2)s(-1)). At the core of the CMS detector sits a high-magnetic-field and large-bore superconducting solenoid surrounding an all-silicon pixel and strip tracker, a lead-tungstate scintillating-crystals electromagnetic calorimeter, and a brass-scintillator sampling hadron calorimeter. The iron yoke of the flux-return is instrumented with four stations of muon detectors covering most of the 4 pi solid angle. Forward sampling calorimeters extend the pseudo-rapidity coverage to high values (vertical bar eta vertical bar <= 5) assuring very good hermeticity. The overall dimensions of the CMS detector are a length of 21.6 m, a diameter of 14.6 m and a total weight of 12500 t.

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The CMS experiment at the CERN LHC

An Introduction to MultiAgent Systems.

The Smart Grid, regarded as the next generation power grid, uses two-way flows of electricity and information to create a widely distributed automated energy delivery network. In this article, we survey the literature till 2011 on the enabling technologies for the Smart Grid. We explore three major systems, namely the smart infrastructure system, the smart management system, and the smart protection system. We also propose possible future directions in each system. colorred{Specifically, for the smart infrastructure system, we explore the smart energy subsystem, the smart information subsystem, and the smart communication subsystem.} For the smart management system, we explore various management objectives, such as improving energy efficiency, profiling demand, maximizing utility, reducing cost, and controlling emission. We also explore various management methods to achieve these objectives. For the smart protection system, we explore various failure protection mechanisms which improve the reliability of the Smart Grid, and explore the security and privacy issues in the Smart Grid.

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Smart Grid — The New and Improved Power Grid: A Survey

Smart Grid - The New and Improved Power Grid:

http://www.nt.ntnu.no/users/skoge/prost/proceedings/ifac2014/media/files/0528.pdf

Cyber-Physical System Security and Impact Analysis

The increasing penetration of proactive agents in electric power distribution systems calls for mechanisms to coordinate their trading activities. The commonly employed centralized and distributed methods for supply-demand coordination are not only limited by hardware requirements but also restrictive for active participation of the market agents. This paper proposes a novel decentralized transactive coordination framework that allows participants to bid and clear transactions via a bilateral interaction process. The framework is based on 1) power consumption flexibility individually reported by demand agents using model-predictive control, 2) bilateral supply-side bidding individually determined by the supply agents using a Markowitz Portfolio Optimization model, and 3) individual simultaneous clearing of transactions by demand agents based on second-price sealed-bid auctions. The suppliers bid in the market to achieve desired returns while minimizing their risks. The demand agents harness their demand flexibility by competitively clearing the supplier bids. Unlike traditional approaches, the proposed framework does not require master nodes to orchestrate transactions and, therefore, facilitates massive participation of market agents. Simulation cases demonstrate that the proposed framework successfully performs the market function for bilateral transactions among thousands of proactive agents.

Decentralized Transactive Energy for Flexible Resources in Distribution Systems

This paper provides a self-healing strategy to deal with catastrophic events when the system vulner- ability analysis indicates that the system is approaching an extreme emergency state. In our approach, the system is divided into smaller islands with consideration of quick restoration. Then an intelligent adaptive load-shedding scheme based on the rate of frequency decline is applied. The proposed scheme is tested on a 179 buses 20 genera- tors sample system and shows very good performance. Due to the uncertainties in power systems, the load- shedding scheme needs to adjust its decision criteria in an auton omous manner. A Reinforcement Learning (RL) technique is discussed and a dynamic simulation with the intelligent load shedding control scheme is described to validate the RL technique.

An intelligent adaptive load shedding scheme

Cyber threats are serious concerns for power systems. For example, hackers may attack power control systems via interconnected enterprise networks. This paper proposes a risk assessment framework to enhance the resilience of power systems against cyber attacks. The duality element relative fuzzy evaluation method is employed to evaluate identified security vulnerabilities within cyber systems of power systems quantitatively. The attack graph is used to identify possible intrusion sce- narios that exploit multiple vulnerabilities. An intrusion response system (IRS) is developed to monitor the impact of intrusion scenarios on power system dynamics in real time. IRS calculates the conditional Lyapunov exponents (CLEs) on line based on the phasor measurement unit data. Power system stability is predicted through the val- ues of CLEs. Control actions based on CLEs will be suggested if power system instability is likely to happen. A generic wind farm control system is used for case study. The effectiveness of IRS is illustrated with the IEEE 39 bus system model.

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Risk assessment framework for power control systems with PMU-based intrusion response system

Current SCADA (Supervisory Control and Data Acquisition) system architecture increases the interconnectivity to/from other distributed networks and services. In addition, within the SCADA networks there are different types of sub-networks and protocols that are used to monitor and control industrial operations. This complex expansion increases the productivity of SCADA networks; however, it also increases security risks and threats. The state-of-the-art Intrusion Detection Systems (IDSs) are not capable enough of detecting anomalies and intrusions that may be aimed to disrupt the SCADA operations. This paper proposes a Distributed Intrusion Detection System (DIDS) based on a community collaboration between multiple agents of anomaly detectors to identify anomaly behaviors in SCADA networks. The proposed architecture for DIDS incorporates the SCADA network topology and connectivity constraints. In this paper, detailed architecture, components, and functions of DIDS are described and attack scenarios are developed to validate the effectiveness of the proposed methodology

Chen-Ching Liu

Papers

Cyber-Physical System Security and Impact Analysis

Decentralized Transactive Energy for Flexible Resources in Distribution Systems

An intelligent adaptive load shedding scheme

Risk assessment framework for power control systems with PMU-based intrusion response system

Detecting cyber intrusions in SCADA networks using multi-agent collaboration