Deception in Finitely Repeated Security Games

Allocating resources to defend targets from attack is often complicated by uncertainty about the attacker’s capabilities, objectives, or other underlying characteristics. In a repeated interaction setting, the defender can collect attack data over time to reduce this uncertainty and learn an effective defense. However, a clever attacker can manipulate the attack data to mislead the defender, influencing the learning process toward its own benefit. We investigate strategic deception on the part of an attacker with private type information, who interacts repeatedly with a defender. We present a detailed computation and analysis of both players’ optimal strategies given the attacker may play deceptively. Computational experiments illuminate conditions conducive to strategic deception, and quantify benefits to the attacker. By taking into account the attacker’s deception capacity, the defender can significantly mitigate loss from misleading attack actions.

Codensity and stone spaces

We present a detailed computation of two codensity monads associated to two canonical functors – the inclusion functor ofFinSetintoTopand the inclusion functor of the category of the powers of the Sierpiński space intoTop. We show that the categories of algebras of the two monads are the categories of Stone spaces and of sober spaces, respectively. A new motivation for defining these classes of spaces is therefore obtained.

Modelling East Asian Calendars in an Open Source Authority Database

This paper discusses issues concerning the creation of conversion tables for East Asian (Chinese, Japanese, Korean) and European calendars and describes the development of an open source calendar database as part of the history of converting East Asian calendars. East Asian calendars encode both astronomical and political cycles. As a result, date conversion must in practice rely on complex look-up tables and cannot be done merely algorithmically. We provide a detailed overview of the history of such conversion tables and find that the modelling of these tables into the digital follows a trend of increasingly detailed computation of chronological time. The Buddhist Studies Time Authority Database was designed to allow computational conversion of the Chinese, the Japanese and the Korean Calendar, between each other, as well as with the Gregorian, proleptic Gregorian and Julian calendar. It relies on the Julian Day Number (JDN) as common referent for all conversions.

Transient fields produced by a cylindrical electron beam flowing through a plasma

The out-of-equilibrium situation in which an initially sharp-edged cylindrical electron beam, that could, e.g., model electrons flowing within a wire, is injected into a plasma is considered. A detailed computation of the subsequently produced magnetic field is presented. The control parameter of the problem is shown to be the ratio of the beam radius to the electron skin depth. Two alternative ways to address analytically the problem are considered: one uses the usual Laplace transform approach, the other one involves Riemann's method in which causality conditions manifest through some integrals of triple products of Bessel functions.

Studying the Expansion Uniformity of Intravascular Stents by the Effect of Laser Cutting Error

Laser cutting error has large influence on the beam width of intravascular stents. Minor random variation in beam width of stents may significantly impact the expansion uniformity. In this paper, the relevant factors that may affect the beam width during the manufacture are investigated. Based on the randomization model, the pattern how the factors affect expansion uniformity is explored, and the method for calculating uniformity index is proposed. A detailed computation is made on the width randomization for the two expansion elements. The results show that with the increase of the value range of beam width, probability of uniformity index decreases gradually; the strengthening factor has large effect on the expansion uniformity. The method is meaningful for studying how the processing error affects expansion uniformity.

A Methodology for Blast Furnase Hearth Wear Analysis

The wear of a blast furnace hearth and the hearth inner profile are highly dependent on the liquid iron flow pattern, refractory temperatures, and temperature distributions at the hot face (the interface between the liquid iron and refractory or the skull). A 3-D CFD hearth model has been developed for predict the hearth erosion and its inner profile. The detailed computation results show that the hot face temperature is location dependant. Based on these discoveries, a new methodology along with new algorithms is established to calculate the hearth erosion and its inner profile. The methodology is to estimate the hearth primary inner profile based on 1-D heat transfer, and to compute the hot face temperature using the 3-D CFD hearth model according to the 1-D pre-estimated and re-estimated profiles. After the hot face temperatures are converged, the hot face positions are refined by a new algorithm, which is based on the difference between the calculated and measured results. The finalized CFD prediction temperatures are in good agreement with the experimental results except at or near the corner and taphole regions. In this paper, the detailed methodology and the new algorithm are presented along with the examples of hearth erosion and inner profile predictions.