Breach Probability Research Articles

Investigation of the influence of temperature-speed mode on the parameters of secondary cooling of continuously casted billet from free-cutting steel

Practically the whole steel, including the free-cutting one, is casting by continuous casting machines (CCM). The technological parameters of the free-cutting steel continuous casting have their features, since the high content of Sulphur and phosphor in the free-cutting steel, necessary for its high machinability, increases the probability of fractures and emergency breach of metal. The purpose of the work was study of influence of temperature-speed mode of A12 free-cutting steel casting on cooling agent consumption in the secondary cooling zone of radial type billet CCM. The CCM mold was 900 long with supporting system on the mold frame of two rows of rollers. The secondary cooling (SC) zone comprised four zones of 340, 2360, 3460 and 3610 mm length. The cooling in the first zone is accomplished by water, in the others – by water-air mist. The study was carried out by application of mathematical simulation method to the process of billet secondary cooling, elaborated by V.N. Selivanov. The temperature of the free-cutting steel billet surface was calculated by zones of secondary cooling at various steel temperature in the tundish. The flow density and water consumption in various SC zones determined, necessary to reach the required variation of billet surface temperature. The dependence of total and specific water consumption for the billet cooling on the metal temperature in the CCM tundish determined.

Analysis of Y00 Protocol Under Quantum Generalization of a Fast Correlation Attack: Toward Information-Theoretic Security

In our previous work, it was demonstrated that the attacker could not pin-down the correct keys to start the Y00 protocol with a probability of one under the assistance of unlimitedly long known-plaintext attacks and optimal quantum measurements on the attacker’s quantum memory. However, there were several assumptions that the Y00 system utilized linear-feedback shift registers as pseudo-random-number generators, and a fast correlation attack was disabled by irregular mapping on the Y00 systems. This study generalizes such an attack to remove the assumptions of the previous work. The framework of the security analyses of this study reiterates two well-known results from the past: (1) Y00 systems would be cryptanalyzed when the system is not designed well; (2) the system is possibly information-theoretically secure when the system is designed well, although the attacker’s confidence in the correct key increases over time but the success probability of key recovery does not reach unity in finite time; (3) the breach probability of the shared keys increases with time. Hence, a key-refreshment procedure for the Y00 protocol is provided herein. Such security analyses are important not only in key refreshment but also in initial key agreement.

Copula-based modeling of earthen levee breach due to overtopping

The level of protection offered by an earthen levee is typically described in terms of flood water level that the levee is capable of containing. If a larger flood occurs, floodwaters exceed the height of the levee and flow over its crest. As the water passes over the top, it may erode the levee, worsening the flooding and potentially causing a breach. In order to determine the annual probability that an earthen levee breaches due to overtopping, multiple flood characteristics such as peak flood water level, or related peak flow discharge, and flood duration need to be characterized statistically by using multivariate statistics. In this study, critical conditions for levee failure are described by using a Clayton copula relating peak flow discharge to flood duration. The obtained model is tested over a real river site located along the Panaro River, in northern Italy, where a 52-year time series of hourly flow discharge and a normal flow rating curve are available. The developed model makes it possible to delimitate the levee failure region within the population of flood events and to statistically describe earthen levee breach due to overtopping. Breach probability is found to be underestimated when the statistical association between peak flow discharge and flood duration is neglected. The proposed copula-based model is therefore important to support the design and construction of earthen levees, and to identify the actions needed to save lives and property when a flood exceeding the levee design limit occurs.

Safe trajectory for an occipital condyle screw: A computer simulation study.

The purpose of this study was to evaluate the feasibility of posterior occipital condyle screw (OCS) placement analysis of the safe trajectory area for screw insertion. Computed tomographic angiography scans of patients (46 males and 27 females) with normal occipitocervical structures were obtained consecutively. Vertebral artery (VA)-occiput distance <4.0 mm was defined as "unfeasible" for OCS fixation, and occipital-atlas angulation was measured to assess the feasibility of screw placement. Next, the placement of 3.5 mm diameter OCS was simulated, the probability of breach of structures surrounding occipital condyles was calculated, and placement parameters were analyzed. OCS placement was feasible in 91.1% (133/146) of occipital condyles, and the feasible probability also presented a significant sex-related difference: The probability was higher for males than for females (95.7% vs. 83.3%, p < 0.05). The incidence of anatomical structures injured under screw placement limitation was 18.8% (VA), 81.2% (hypoglossal canal), 59.4% (occipital-atlas joint), and 40.6% (occiput bone surface). There were no significant differences between the left and right condyles in relation to the measured parameters (p > 0.05). The screw range of motion was significantly smaller in females than in males (p < 0.05). The feasibility of OCS placement and OCS range of motion were significantly greater in the kyphosis group (>5°) than in the other two groups (p < 0.05). OCS placement is a feasible technique for occipital-cervical fusion. The male group and occipitocervical region kyphosis group had a wider available space for OCS placement. Tangent angulation may be useful for the accurate and safe placement of an OCS.

Improved Methods for Estimating Flood Depth Exceedances Within Storm Surge Protection Systems.

Contemporary studies conducted by the U.S. Army Corps of Engineers estimate probability distributions of flooding on the interior of ring levee systems by estimating surge exceedances at points along levee system boundaries, calculating overtopping volumes generated by this surface, then passing the resulting volumes of water through a drainage model to calculate interior flood depths. This approach may not accurately represent the exceedance probability of flood depths within the system interior; a storm producing 100-year surge at one point is unlikely to simultaneously produce 100-year surge levels everywhere around the system exterior. A conceptually preferred approach estimates surge and waves associated with a large set of storms. Each storm is run through the interior model separately, and the resulting flood depths are weighted by a parameterized likelihood of each synthetic storm. This results in an empirical distribution of flood depths accounting for geospatial variation in any individual storm's characteristics. This method can also better account for the probability of levee breaches or other system failures. The two methods can produce different estimates of flood depth exceedances and damage when applied to storm surge flooding in coastal Louisiana. Even differences in flood depth exceedances of less than 0.2 m can still produce large differences in projected damage. This article identifies and discusses differences in estimated flood depths and damage produced by each method within multiple Louisiana protection systems. The novel coupled dynamics approach represents a step toward enabling risk-based design standards.

Decision support for the optimal allocation of security controls

We present constrained optimization models that could be used in a decision support system for configuring security solutions for an information systems infrastructure. We begin with a deterministic model that uses security breach probabilities as parameters. Since security breach data is not easily available, breach probabilities are often estimated via surveys, which could lead to estimation errors. To develop robust solutions in the presence of estimation errors, we then present a stochastic optimization model that handles uncertainties in breach probability estimations. Our model solutions incorporate quantifiable security risk and business impact as the models are detailed enough to capture various categories of security attacks, and different levels of security protection and loss values for data and applications. We demonstrate the utility of our models by proposing security solutions for a realistic IT infrastructure using breach probability estimates derived from surveys.

Toward Encrypted Video Tampering Detection and Localization Based on POB Number System Over Cloud

The unlimited growth in the amount of multimedia content has shifted the global infrastructure to the cloud-based multimedia hosting. However, the high probability of security breaches of the content is increasing demand for secure solutions toward this end. One such feasible solution is to encrypt the content to unreadable form before outsourcing to the cloud-based servers. In this paper, the media information, specifically the video content is distributed into multiple random shares based on the permutation ordered binary number system. The information remains fully concealed without any leakage at the cloud servers. Even if the attacks endanger the integrity of the information, the proposed scheme is enriched with the capability of chalking out accurately the altered pixels. These tampered regions are subsequently reflected in the reconstructed video frames obtained at authentic entity end possessing the secret keys required to build back the original content. Moreover, the proposed scheme is capable of detecting temporal attacks on the video frames by employing sequence-based authentication bits. The robustness of the proposed scheme has been validated under different attack scenarios and the scheme is found to be performing satisfactorily well.

A Privacy-Enhanced Friending Approach for Users on Multiple Online Social Networks

Online social network users share their information in different social sites to establish connections with individuals with whom they want to be a friend. While users share all their information to connect to other individuals, they need to hide the information that can bring about privacy risks for them. As user participation in social networking sites rises, the possibility of sharing information with unknown users increases, and the probability of privacy breaches for the user mounts. This work addresses the challenges of sharing information in a safe manner with unknown individuals. Currently, there are a number of available methods for preserving privacy in order to friending (the act of adding someone as a friend), but they only consider a single source of data and are more focused on users’ security rather than privacy. Consequently, a privacy-preserving friending mechanism should be considered for information shared in multiple online social network sites. In this paper, we propose a new privacy-preserving friending method that helps users decide what to share with other individuals with the reduced risk of being exploited or re-identified. In this regard, the first step is to calculate the sensitivity score for individuals using Bernstein’s polynomial theorem to understand what sort of information can influence a user’s privacy. Next, a new model is applied to anonymise the data of users who participate in multiple social networks. Anonymisation helps to understand to what extent a piece of information can be shared, which allows information sharing with reduced risks in privacy. Evaluation indicates that measuring the sensitivity of information besides anonymisation provides a more accurate outcome for the purpose of friending, in a computationally efficient manner.

A game-theoretic analysis of information security investment for multiple firms in a network

The application of Internet of Things promotes the cooperation among firms, and it also introduces some information security issues. Due to the vulnerability of the communication network, firms need to invest in information security technologies to protect their confidential information. In this paper, considering the multiple-step propagation of a security breach in a fully connected network, an information security investment game among n firms is investigated. We make meticulous theoretic and experimental analyses on both the Nash equilibrium solution and the optimal solution. The results show that a larger network size (n) or a larger one-step propagation probability (q) has a negative effect on the Nash equilibrium investment. The optimal investment does not necessarily increase in n or q, and its variation trend depends on the concrete conditions. A compensation mechanism is proposed to encourage firms to coordinate their strategies and invest a higher amount equal to the optimal investment when they make decisions individually. At last, our model is extended by considering another direct breach probability function and another network structure, respectively. We find that a higher connection density of the network will result in a greater expected cost for each firm.

Optimal Level and Allocation of Cybersecurity Spending: Model and Formula

This paper presents mathematical models for cyber breach probability as function of security spending in protecting a firm’s ICT systems. We derive optimal level of security investment as percentage of value-at-risk. We show that the upper bound of optimal investment can be 1/e, 1/√2π or other percentages of value-at-risk, depending on the cyber breach probability model. We apply the models to derive optimal security budget allocation for protecting ICT systems with multiple areas of vulnerability and multiple data assets. Our analysis highlights the importance of security measures to cover the full spectrum of areas of vulnerability; neglecting one area of vulnerability can render the security investment ineffective and wasteful. Moreover, optimal economic value can be achieved by differential treatment of a firm’s high-value data assets.

Multilateral Contracts in Information Security Outsourcing

Coordinating the efforts of contractual parties in information security outsourcing is challenging given that a managed security service provider (MSSP) and its contractual partners cannot perfectly observe or verify each other's investment. This study examines the use of multilateral contracts in addressing the double moral hazard problem for managed security services. We present a comprehensive investigation of multilateral contracts, and analyze the influence of externalities and breach probabilities on contingent payments. The results show that a normalized externality, the ratio between a firm's externality and its investment efficiency, dictates the levels of contingent payments in multilateral contracts. We further demonstrate the flexibility of designing multilateral contracts, and discuss three contract types: the equal-refund contract, the externality contract, and the risk-free contract. Each contract type brings different benefits to the contractual parties and can be chosen based on their security management preferences. At last, we show how to extend these contract types when the number of firms increases.

Stability evaluation and prediction of the Dongla reactivated ancient landslide as well as emergency mitigation for the Dongla Bridge

The Dongla Bridge, Muli County, China, is a key access road between counties in Sichuan Province and the only traffic facility for an important 500-kV electricity substation which provides power to nearby counties. In June 2011, during the bridge construction, an unknown landslide, subsequently named the Dongla Ancient Landslide (DAL), was encountered. Local reactivation of a portion of the DAL, termed the Dongla Reactivated Landslide (DRL), was indicated by evident ground deformation at the Dongla Bridge. In spite of this, transportation of some heavy electrical equipment to the substation was scheduled on 9 May 2013. So, to guarantee the stability and security of the bridge became a primary emergency task. Detailed field investigations of the landslide occurrence, monitoring and emergency mitigation construction were carried out in the period between 2011 and 2014. This resulted in a temporary stabilization of the revived landslide and ensured the timely transportation of the heavy electrical equipment. It is thought that the revival mechanism of the DRL is creep, translational sliding, and was mainly triggered by artificial slope-cutting, but also influenced by precipitation, river erosion, and man-made activities in the form of small-scale mining operations. Following complete failure of the DRL, the probability of landslide-dam and dam breach is proved to be small by risk analyses. This paper can provide an insight into the problems associated with the interaction between the human structures and landslide instabilities.

IT Governance, Security Outsourcing, and Cybersecurity Breaches: Evidence from the U.S. Higher Education

Prior research on information security management often considers information security as an operational decision instead of a strategic decision, and there is lack of empirical research that uses archival data to examine cybersecurity breaches. We study how two important strategic decisions with regard to information systems -- IT governance, and the outsourcing of information security -- affect the likelihood of cybersecurity breaches by using a sample of 505 U.S. higher education institutions over a 4-year period. We find that a university with centralized IT decision making is associated with fewer cybersecurity breaches. By our estimate, a one standard deviation increase in IT centralization is associated with a reduction in the probability of a cybersecurity breach by 3.5%. Interestingly, the effect of centralized IT governance is contingent on the complexity of a university’s computing environment -- schools with sophisticated IT infrastructure benefit more from centralized governance. In addition, we find that correcting for the self-selection bias, universities that opt for outsourcing their information security have a lower likelihood of suffering from a cybersecurity breach. We discuss the implications for research and practices.

An economic model to evaluate information security investment of risk-taking small and medium enterprises

This paper analyzes information security investment decisions made by risk taking small and medium enterprises (SMEs) using the expected utility approach. It then compares these decisions to ones made by a risk neutral firm. We find that risk takers are inclined to prioritize an information set's vulnerability over its value when making investment decisions. We also find that a risk taking firm may invest a larger amount in protecting a set than the risk neutral firm when the effectiveness of the investment in lowering breach probability is low. Finally, we show that for a group of information sets of equal value and varying vulnerabilities, the risk neutral decision maker will diversify security investment to a greater extent than the risk taker. As a result, the risk taker will invest a larger amount than the risk neutral firm would when protecting the high risk sets in the group. The results provide guidance to information security vendors when tailoring products to suit small businesses.

Relation between Financial Flexibility and Probability of Default: KMV Model

Background/Objectives: Investment sources are allocated to economic activities through financial markets. One important topic is studying and evaluation of credit risks that is breach probability for reimbursement of granted facilities by customers. Methods/Statistical Analysis: This research evaluated the effects of financial flexibility independent variable on the probability of default dependent variable. This was investigated by gathering data from 101 companies receiving bank facilities from 2009 to 2013. To measure credit risk of companies, KMV Model has been used. The study hypotheses tested using combinational data, and for data analyzing and evaluating multi-variable regression model and study’s hypotheses test, we used E-views software. Findings: This research identifies some of the effective factors related to financial flexibility, as one of the modern financial patterns and strategies, affecting probability of default. The results show that there is a reverse and significant relation between financial flexibility and default probability. Also, there is a reverse and significant linear relation between flexibility and default probability of companies with high and low financial leverages, too with small and large sizes. Thus, relation rate varies in different levels of firm sizes and financial leverages, which indicates the effect of company size and financial leverage variables on relations between independent and dependent variables. Application/Improvements: Regarding to the results, it is recommended that banks andfinancial institutions and companies that sell credits notice financial flexibility, financial leverage, company sizes, and the effects of these variables on debt default when granting facilities.

Privacy Enhancing Technologies (PETs) and Investment Strategies for a Data Market

This paper analyses cases where data collectors adopt privacy enhancing technologies (PETs) for a data market, and investigates investment strategies for privacy protection technologies. This paper shows the firm has an incentive to invest in privacy enhancing technologies if consumers feel there is a psychological privacy cost. This paper also discusses firm's investment strategies on privacy, and shows that a firm will invest more on privacy protection as the influence of privacy awareness groups and privacy costs increase, and a firm will not invest in privacy protection when privacy breach probability is deemed to be low.

Economics of Information Security Investment Integrated with IDS and Attacker’s Behavior

ROSI (Return On Security Investment) has attracted a great deal of attention in recent years. By inheriting Gordon and Loeb 2002 security breach probability function, we present an adaptive economics model of investment in information security integrating dynamic characteristics of outside threat probability and detective mechanism, and deduce some guidelines for optimal investment amount.

Canal breach risk assessment for improved asset management

Advances in inundation modelling software, computer hardware and national data sets mean that it is now practical to use full solutions of the two-dimensional (2D) shallow water equations (SWE) to undertake national-scale modelling of breach inundation. Such modelling enables much improved asset management activities, which lead to reduced risk to life, lower risk of damage to properties and a much better targeting of investment by asset owners. This paper describes how a 2D SWE inundation modelling system was designed and applied to the UK Canal and River Trust canal system as part of a quantitative high-level risk assessment framework. The framework includes a new approach for estimating breach probability and hydrographs in the canal system for potential embankment and culvert failures. An innovative automated model build-and-run process using Isis 2D software was applied to model inundation in urban areas. Predicted likely loss of life and property damage outputs were used to generate a risk chart to prioritise asset inspection and maintenance.

Inundation risk for embanked rivers

Abstract. The Flood Frequency Analysis (FFA) concentrates on probability distribution of peak flows of flood hydrographs. However, examination of floods that haunted and devastated the large parts of Poland lead us to revision of the views on the assessment of flood risk of Polish rivers. It turned out that flooding is caused not only by the overflow of the levee crest but also due to the prolonged exposure to high water on levees structure causing dangerous leaks and breaches that threaten their total destruction. This is because the levees are weakened by long-lasting water pressure and as a matter of fact their damage usually occurs after the culmination has passed the affected location. The probability of inundation is the total of probabilities of exceeding embankment crest by flood peak and the probability of washout of levees. Therefore, in addition to the maximum flow one should also consider the duration of high waters in a river channel. In the paper the new two-component model of flood dynamics: "Duration of high waters–Discharge Threshold–Probability of non-exceedance" (DqF), with the methodology of its parameter estimation was proposed as a completion to the classical FFA methods. Such a model can estimate the duration of stages (flows) of an assumed magnitude with a given probability of exceedance. The model combined with the technical evaluation of the probability of levee breaches due to the duration (d) of flow above alarm stage gives the annual probability of inundation caused by the embankment breaking. The results of theoretical investigation were illustrated by a practical example of the model implementation to the series of daily flow of the Vistula River at Szczucin. Regardless of promising results, the method of risk assessment due to prolonged exposure of levees to high water is still in its infancy despite its great cognitive potential and practical importance. Therefore, we would like to point out the need for and usefulness of the DqF model as complementary to the analysis of the flood peak flows, as in classical FFA. The presented two-component model combined with the routine flood frequency model constitutes a new direction in FFA for embanked rivers

Impact scenario models for probabilistic risk-based design for ship–ship collision

A number of authors have proposed probabilistic risk based ship design for ship–ship collision, conditional to the local trading area of a vessel. The probability of collision and consequences are determined based on the traffic conditions in which a vessel is expected to operate. This paper investigates the adequacy of currently available models for impact scenarios, i.e. models linking the traffic conditions to the conditions at the moment of collision. An exploratory statistical model is presented to establish such a link. A probabilistic risk based design case study is performed for a fleet of RoPax vessels trading on a specified route in the Gulf of Finland. The available impact scenario models from the literature are compared with the developed probabilistic evasive maneuvering model. The results show that the impact scenario models have a very significant influence to the calculated hull breach probabilities. No well-justified impact scenario models are presently available and also the presented probabilistic evasive maneuvering model is burdened with uncertainty. Hence, to move toward a probabilistic risk based ship design paradigm for ship–ship collision in a local trading area, more focus and research is needed to establish a credible link.