Malicious attacks against power systems are investigated, in which an adversary controls a set of meters and is able to alter the measurements from those meters. Two regimes considered. The strong attack regime where sufficient number so that network state becomes unobservable by control center. For this regime, smallest attacked capable causing unobservability characterized using graph theoretic approach. By casting problem as one minimizing supermodular functional, identifying vulnerable...

Stability is an important constraint in power system operation. Often trial and error heuristics are used that can be costly imprecise. A new methodology eliminates the need for repeated simulation to determine a transiently secure operating point presented. The theoretical development straight-forward: dynamic equations converted numerically equivalent algebraic then integrated into standard OPF formulation. Implementation issues results discussed context of 162-bus system.

The problem of constructing malicious data attack smart grid state estimation is considered together with countermeasures that detect the presence such attacks. For adversary, using a graph theoretic approach, an efficient algorithm polynomial-time complexity obtained to find minimum size unobservable When does not exist due restrictions meter access, attacks are constructed minimize residue energy while guaranteeing certain level increase mean square error. control center, computationally...

The problem of system collapse or blackout characterized by a local severe voltage depression is generally believed to be associated with inadequate VAR support at key busses. authors discuss techniques for improving the security respect this index. effect adding capacitors are examined. They also present continuation technique that redistributes generation optimal operating condition minimum singular value index.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML"...

The deregulated electricity market calls for robust optimal power flow (OPF) tools that can provide a) deterministic convergence; b) accurate computation of nodal prices; c) support both smooth and nonsmooth costing a variety resources services, such as real energy, reactive voltages support, etc.; d) full active modeling large-scale systems; e) satisfactory worst-case performance meets the real-time dispatching requirement. Most prior research on OPF has focused issues in context regulated...

In order to design an efficient communication scheme and examine the efficiency of any networked control architecture in smart grid applications, we need characterize statistically its information source, namely power itself. Investigating statistical properties grids has immediate benefit providing a natural simulation platform, producing large number test cases with realistic topologies, scalable network size, electrical parameter settings. The second is that one can start analyzing...

Data attacks on state estimation modify part of system measurements such that the tempered cause incorrect estimates. Attack techniques proposed in literature often require detailed knowledge parameters. Such information is difficult to acquire practice. The subspace methods presented this paper, other hand, learn operating from and launch accordingly. Conditions for existence an unobservable attack are obtained under full partial measurement models. Using estimated subspace, two strategies...

Voltage collapses which have a period of slowly decreasing voltage followed by an accelerating collapse in are analyzed based on center manifold model. The essence this model is that the system dynamics after bifurcation captured trajectory. It computable allows prediction collapse. Both physical explanations and computational considerations presented. use static dynamic models clarified to explain demonstrated simple power model.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML"...

This paper describes the optimal power flow (OPF) architecture implemented in MATPOWER, an open-source Matlab system simulation package. It utilizes extensible that allows user to easily add new variables, constraints and costs standard OPF problem formulation while preserving structure needed use pre-compiled solvers. A software object is used encapsulate definition of formulation, manage corresponding named sets costs, handle all tedious index maintenance tasks. The design has advantage...

Journal Article Use of Azithromycin for the Treatment Campylobacter Enteritis in Travelers to Thailand, an Area Where Ciprofloxacin Resistance Is Prevalent Get access Robert A. Kuschner, Kuschner From Division Communicable Diseases and Immunology, Walter Reed Army Institute Research, Washington, D.C.; Surgeon's Office, III Marine Expeditionary Force, Okinawa, Japan; Armed Forces Research Medical Sciences, Bangkok, Thailand; Naval Unit 2, Jakarta, Indonesia Reprints or correspondence: Dr....

This paper proposes a method for choosing the best transmission system expansion plan considering probabilistic reliability criterion (/sub R/LOLE). The minimizes investment budget constructing new lines subject to criteria, which consider uncertainties of elements. Two criteria are used as constraints. One is R/LOLE/sub TS/) constraint, and other bus/nodal Bus/) constraint. proposed models problem an integer programming problem. It solves optimal strategy using branch bound that utilizes...

This work presents a stochastic optimization framework for operations and planning of an electricity network as managed by Independent System Operator. The objective is to maximize the total expected net benefits over horizon, incorporating costs consumption, generation, ancillary services, load-shedding, storage load-shifting. overall could be characterized secure, stochastic, combined unit commitment AC optimal power flow problem, solving state-dependent schedule pre-specified time...

Centrality measures are used in network science to rank the relative importance of nodes and edges a graph. Here we define new centrality for power grid structure that based on its functionality. We show analysis graph theory can be generalized with electrical parameters taken into account. In paper experiment proposed NYISO-2935 system IEEE 300-bus system. analyze distribution order identify important or branches which essential terms vulnerability. also present discuss number interesting...

Malicious attacks against power system state estimation are considered. It has been recently observed that if an adversary is able to manipulate the measurements taken at several meters in a system, it can sometimes change estimate control center way will never be detected by classical bad data detectors. However, cases when not perform this attack, was clear what might look like. An easily computable heuristic developed find adversarial all cases. This recovers undetectable attacks, but...

The problem of characterizing impacts data quality on real-time locational marginal price (LMP) is considered. Because the LMP computed from estimated network topology and system state, bad that cause errors in processing state estimation affect LMP. It shown power space partitioned into regions convex polytopes. Under different models, worst case are analyzed. Numerical simulations used to illustrate performance for IEEE-14 IEEE-118 networks.

Purpose According to the authors’ research, while top-level executives look forward potential of artificial intelligent systems in their firms, line managers are much more skeptical. This article advises on i8mplementation strategy. Design/methodology/approach Drawing findings from Accenture’s survey 1,770 14 countries and interviews with 37 senior responsible for digital transformation, authors have identified patterns managers’ attitudes offer strategies effective adoption new technology....

The short-term forecasting of real-time locational marginal price (LMP) and network congestion is considered from a system operator perspective. A new probabilistic technique proposed based on multiparametric programming formulation that partitions the uncertainty parameter space into critical regions which conditional probability distribution LMP/congestion obtained. method incorporates load/generation forecast, time varying operation constraints, contingency models. By shifting computation...

Roads can have negative impacts on wildlife through indirect effects such as fragmentation of habitat, or direct fatal collisions with vehicles. Wildlife deaths British roads number in the millions per year, so resulting carcasses represent a substantial carrion biomass available food for scavengers. By removing roadkill urban areas, scavengers perform valuable ecosystem service, but rapid removal these by could bias estimates wildlife. In order to evaluate scale and context scavenging, we...

Top business executives—“important people in big companies”—are both visible and inaccessible. This situation poses unique challenges for the sociologist interested learning about what executives think do. To go beyond caricature or public relations imagery, researchers must devise creative strategies getting access data. article offers some reflections on barriers to data how they can be surmounted, with specific attention focused importance of preparation—of researcher being researched.

Preface 1. Introduction Bridging Determinism and Choice The Power-Process Perspective History Matters Dissimilar Logics in an Organizational Context Choice, Change, Worldviews Understanding Technological Change Case Studies Research Methods Site Selection Reporting Findings Organization of the Book 2. Technology as a Power Tool: Aircraft Company Industrial 1: Flexible Machining System Choosing Between Technologies Symptoms Versus Causes Bringing Interests to Surface Within Finessing ROI...

Bluetooth is a novel promising local area wireless technology designed to enable voice and data communication among various electronic devices. We believe that networks will provide reliable, flexible cost-efficient telecommunication support for the post-deregulation electric power systems. Though not specified in version 1.0 of specification, by way multi-hop routing (characteristic ad hoc networks) within scatternet offer new exciting extension this technology. The topology such an ad-hoc...

Background Animal and human trypanosomiasis are constraints to both animal health in Sub-Saharan Africa, but there is little recent evidence as how these parasites circulate wild hosts natural ecosystems. The Luangwa Valley Zambia supports high densities of tsetse flies (Glossina species) recognised an historical sleeping sickness focus. objective this study was characterise the nature reservoir community for absence influence from domesticated hosts. Methodology/Principal Findings A...

Highlights some of the major conceptual and methodological issues involved in organisational buying behaviour. Aims to avoid pitfalls utilisation research regarding specified — at same time stimulating aimed resolution these issues. Reviews current status behaviour, follows this by identifying five potential groups users information on Goes focus research. Suggests new directions which, if implemented, could help advance relevance quality States that academic studies, directly concerned with...