Impact estimation using data flows over attack graphs

We propose a novel approach to estimating the impact of an attack using a data model and an impact model on top of an attack graph. The data model describes how data flows between nodes in the network -- how it is copied and processed by softwares and hosts -- while the impact model models how exploitation of vulnerabilities affects the data flows with respect to the confidentiality, integrity and availability of the data. In addition, by assigning a loss value to a compromised data set, we can estimate the cost of a successful attack. We show that our algorithm not only subsumes the simple impact estimation used in the literature but also improves it by explicitly modeling loss value dependencies between network nodes. With our model, the operator will be able to use less time when comparing different security patches to a network

Assessing Security Risk to a Network Using a Statistical Model of Attacker Community Competence

We propose a novel approach for statistical risk modeling of network attacks that lets an operator perform risk analysis using a data model and an impact model on top of an attack graph in combination with a statistical model of the attacker community exploitation skill. The data model describes how data flows between nodes in the network -- how it is copied and processed by softwares and hosts -- while the impact model models how exploitation of vulnerabilities affects the data flows with respect to the confidentiality, integrity and availability of the data. In addition, by assigning a loss value to a compromised data set, we can estimate the cost of a successful attack. The statistical model lets us incorporate real-time monitor data from a honeypot in the risk calculation. The exploitation skill distribution is inferred by first classifying each vulnerability into a required exploitation skill-level category, then mapping each skill-level into a distribution over the required exploitation skill, and last applying Bayesian inference over the attack data. The final security risk is thereafter computed by marginalizing over the exploitation skill

Personalized Decentralized Communication

Search engines, portals and topic-centered web sites are all attempts to create more or less personalized web-services. However, no single service can in general fulfill all needs of a particular user, so users have to search and maintain personal profiles at several locations. We propose an architecture where each person has his own information management environment where all personalization is made locally. Information is exchanged with other’s if it’s of mutual interest that the information is published or received. We assume that users are self-interested, but that there is some overlap in their interests. Our recent work has focused on decentralized dissemination of information, specifically what we call decentralized recommender systems. We are investigating the behavior of such systems and have also done some preliminary work on the users’ information environment

Case-based reasoning combined with statistics for diagnostics and prognosis

Many approaches used for diagnostics today are based on a precise model. This excludes diagnostics of many complex types of machinery that cannot be modelled and simulated easily or without great effort. Our aim is to show that by including human experience it is possible to diagnose complex machinery when there is no or limited models or simulations available. This also enables diagnostics in a dynamic application where conditions change and new cases are often added. In fact every new solved case increases the diagnostic power of the system. We present a number of successful projects where we have used feature extraction together with case-based reasoning to diagnose faults in industrial robots, welding, cutting machinery and we also present our latest project for diagnosing transmissions by combining Case-Based Reasoning (CBR) with statistics. We view the fault diagnosis process as three consecutive steps. In the first step, sensor fault signals from machines and/or input from human operators are collected. Then, the second step consists of extracting relevant fault features. In the final diagnosis/prognosis step, status and faults are identified and classified. We view prognosis as a special case of diagnosis where the prognosis module predicts a stream of future features

Värdegrundsarbete och livskunskap i skolan - Hur ser det ut? Går det att utveckla?

Syfte Vi vill undersöka hur man på ett konkret sätt arbetar med värdegrundsfrågor på en skola samt komma med teoretiska förslag på hur man kan arbeta med livskunskap i skolan som ett integrerat skolämne. Frågeställningar I vårt arbete avser vi behandla dessa frågeställningar: Hur arbetar skolan med värdegrundsfrågor? Vad anser elever och lärare på skolan om arbetet med värdegrundsfrågor? Hur kan man arbeta med livskunskap? Metod Vi har valt att intervjua tre lärare som undervisar i ämnet livskunskap. Detta för att ta reda på hur de ser på ämnet och vilka utvecklingsmöjligheter samt problem som lärarna ser med livskunskap. Intervjuerna gjordes enskilt och muntligt. Frågorna var öppet ställda där lärarna fick chansen att utveckla sina tankar kring undervisning i livskunskap. Dokumentationen skedde genom anteckningar. Under intervjutillfällena var vi båda närvarande. Vi valde också att intervjua tre elevgrupper med fyra elever i varje grupp där vi fokuserade på hur de upplevde undervisningen. Frågorna var även här öppet ställda och metoden som användes var fokusgrupper. Resultat Vi har undersökt en högstadieskola i Kungsbacka. Där har vi granskat ett pågående värdegrundsarbete. Vi kan konstatera att detta arbete är i början av en process där man har en hel del att utveckla för att få en så optimal utbildning i detta ämne som möjligt. Som det är nu så är kvaliteten på dessa lektioner mycket beroende av vilken lärare som håller lektionerna. Lärarna får ett stort individuellt ansvar för upplägget. Lärarna känner dock själva att de skulle vilja ha mer utbildning och ett större övningsförråd för att lektionerna skulle bli bättre och mer givande för eleverna. Både lärare och elever anser dock att det är bra att man har värdegrund på schemat och att det gör nytta för stämningen i klassen. De anser också att det är utvecklande för både elever och lärare att arbeta med detta ämne. Vi anser att det inte finns något facit för hur man ska arbeta med livskunskap men det finns ett antal saker att tänka på för att få så bra och givande lektione

Enhancing Web-Based Configuration with Recommendations and Cluster-Based Help

In a collaborative project with Tacton AB, we have investigated new ways of assisting the user in the process of on-line product configuration. A web-based prototype, RIND, was built for ephemeral users in the domain of PC configuration

Quantifying and estimating additive measures of interaction from case-control data

In this paper we develop a general framework for quantifying how binary risk factors jointly influence a binary outcome. Our key result is an additive expansion of odds ratios as a sum of marginal effects and interaction terms of varying order. These odds ratio expansions are used for estimating the excess odds ratio, attributable proportion and synergy index for a case-control dataset by means of maximum likelihood from a logistic regression model. The confidence intervals associated with these estimates of joint effects and interaction of risk factors rely on the delta method. Our methodology is illustrated with a large Nordic meta dataset for multiple sclerosis. It combines four studies, with a total of 6265 cases and 8401 controls. It has three risk factors (smoking and two genetic factors) and a number of other confounding variables.Comment: Published at http://dx.doi.org/10.15559/17-VMSTA77 in the Modern Stochastics: Theory and Applications (https://www.i-journals.org/vtxpp/VMSTA) by VTeX (http://www.vtex.lt/

A Diesel Engine Model for Dynamic Drive Cycle Simulations

The development and implementation of a diesel engine combustion system simulation model is described. The model is a crank angle based combustion model, which uses the conditions in the intake and exhaust manifolds together with the fuel injection signal from the engine control unit to estimate the in-cylinder pressure throughout a complete combustion cycle. The model is implemented in Matlab. Furthermore, a Simulink coupling has been developed and implemented such that the combustion model can be connected directly to a Simulink mean value model of an engine air system. The coupling makes the combustion model act like a continuous source and a continuous sink in a mean value model. The coupling makes it possible to continuously simulate an engine in steady-state or transient operation, while the combustion model produces estimated cylinder pressure traces for each combustion cycle. This makes it possible to estimate fuel consumption and to couple the model with emission models which use the cylinder pressure or the rate of heat release as input. The model is developed, calibrated and verified using measured data from a 2.4 liter Volvo diesel engine, equipped with a turbocharger, an exhaust gas recirculation system, and a common rail injection system. The combustion model estimates IMEPnet with a correlation factor of 0.995 for the used data. The simulation time is in the range between 1 and 25 milliseconds for one combustion cycle on a standard computer, depending on the implementation

Information Filtering with Collaborative Interface Agents

This report describes a distributed approach to social filtering based on the agent metaphor. Firstly, previous approaches are described, such as cognitive filtering and social filtering. Then a couple of previously implemented systems are presented and then a new system design is proposed. The main goal is to give the requirements and design of an agent-based system that recommends web-documents. The presented approach combines cognitive and social filtering to get the advantages from both techniques. Finally, a prototype implementation called WebCondor is described and results of testing the system are reported and discussed

High-Speed Vision and Force Feedback for Motion-Controlled Industrial Manipulators

Over the last decades, both force sensors and cameras have emerged as useful sensors for different applications in robotics. This thesis considers a number of dynamic visual tracking and control problems, as well as the integration of these techniques with contact force control. Different topics ranging from basic theory to system implementation and applications are treated. A new interface developed for external sensor control is presented, designed by making non-intrusive extensions to a standard industrial robot control system. The structure of these extensions are presented, the system properties are modeled and experimentally verified, and results from force-controlled stub grinding and deburring experiments are presented. A novel system for force-controlled drilling using a standard industrial robot is also demonstrated. The solution is based on the use of force feedback to control the contact forces and the sliding motions of the pressure foot, which would otherwise occur during the drilling phase. Basic methods for feature-based tracking and servoing are presented, together with an extension for constrained motion estimation based on a dual quaternion pose parametrization. A method for multi-camera real-time rigid body tracking with time constraints is also presented, based on an optimal selection of the measured features. The developed tracking methods are used as the basis for two different approaches to vision/force control, which are illustrated in experiments. Intensity-based techniques for tracking and vision-based control are also developed. A dynamic visual tracking technique based directly on the image intensity measurements is presented, together with new stability-based methods suitable for dynamic tracking and feedback problems. The stability-based methods outperform the previous methods in many situations, as shown in simulations and experiments