Yet another optimisation article

The author addresses the question: how do we achieve a fast program? For many programmers, performance is something you pay continuous attention to as you program. Every time you write a fragment of code, you consider the performance implications and code the program to maximize performance. Some performance work comes from architectural decisions, some from more tactical optimization activity. The author considers a specific set of steps for program optimization     

Yet another cybersecurity risk assessment framework

IT systems pervade our society more and more, and we become heavily dependent on them. At the same time, these systems are increasingly targeted in cyberattacks, making us vulnerable. Enterprise and cybersecurity responsibles face the problem of defining techniques that raise the level of security. They need to decide which mechanism provides the most efficient defense with limited resources. Basically, the risks need to be assessed to determine the best cost-to-benefit ratio. One way to achieve this is through threat modeling; however, threat modeling is not commonly used in the enterprise IT risk domain. Furthermore, the existing threat modeling methods have shortcomings. This paper introduces a metamodel-based approach named Yet Another Cybersecurity Risk Assessment Framework (Yacraf). Yacraf aims to enable comprehensive risk assessment for organizations with more decision support. The paper includes a risk calculation formalization and also an example showing how an organization can use and benefit from Yacraf.

     

UK bank fraud gang busted

Six fraudsters have been sent down for a total of 15 and a half years, after using the Internet for social engineering purposes to swindle three UK banks out of £350 000.     

Yet another storage technique for lr parsing tables

A submatrix storage scheme for sparse matrices is presented which has been found useful for storing LR parsing tables. It is not the most compact representation but it is easy to use and of order (1) in speed of access. The method is compared with the two most popular methods of storing LR parsing tables which use ‘linear lists’ and ‘row displacement’. Results of using the submatrix method to store the parsing tables for the Pascal language are included.     

Yet another approach to understanding news event evolution

World Wide Web - With information explosion on the Internet, only returning ranked documents by search engines cannot satisfy people’s requirements on news events understanding. A more...     

Yet another algorithm which can generate topography map

This paper presents an algorithm to form a topographic map resembling to the self-organizing map. The idea stems on defining an energy function which reveals the local correlation between neighboring neurons. The larger the value of the energy function, the higher the correlation of the neighborhood neurons. On this account, the proposed algorithm is defined as the gradient ascent of this energy function. Simulations on two-dimensional maps are illustrated.     

Yet another application of a binomial recurrence order statistics

We investigate the moments of the maximum of a set of i.i.d geometric random variables. Computationally, the exact formula for the moments (which does not seem to be available in the literature) is inhibited by the presence of an alternating sum. A recursive expression for the moments is shown to be superior. However, the recursion can be both computationally intensive as well as subject to large round-off error when the set of random variables is large, due to the presence of factorial terms. To get around this difficulty we develop accurate asymptotic expressions for the moments and verify our results numerically.     

Yet another improvement over the Mu–Varadharajan e-voting protocol

In this paper we present a fully functional RSA/DSA-based e-voting protocol for online elections that corrects and improves a scheme previously proposed by Lin- Hwang-Chang [I. Lin, M. Hwang, C. Chang, Security enhancement for anonymous secure e-voting over a network, Comput. Stand. Interfaces 25 (2) (2003) 131–139.]. We found that Lin-Hwang-Chang's scheme and a recent modification of it by Hwang-Wen-Hwang [S. Hwang, H. Wen, T. Hwang, On the security enhancement for anonymous secure e-voting over computer network, Comput. Stand. Interfaces 27 (2) (2005) 163–168.] have an important weakness. Moreover, the scheme proposed by Yang-Lin-Yang [C. Yang, C. Lin, H. Yang, Improved anonymous secure e-voting over a network, Information and Security 15 (2) (2004) 185–191.] also suffers from this same problem. We describe in detail our findings and propose a new scheme to overcome the weakness we found in these schemes effectively. Finally, we describe the implementation details of our protocol and present its preliminary performance evaluation.     

基于密集子图的银行电信诈骗检测方法

目前银行对电信诈骗的标记数据积累少，人工标记数据的代价大，导致电信诈骗检测的有监督学习方法可使用的标记数据不足。针对这个问题，提出一种基于密集子图的无监督学习方法用于电信诈骗的检测。首先，通过在账户-资源（IP地址和MAC地址统称为资源）网络搜索可疑度较高的子图来识别欺诈账户；然后，设计了一种符合电信诈骗特性的子图可疑度量；最后，提出一种磁盘驻留、线性内存消耗且有理论保障的可疑子图搜索算法。在两组模拟数据集上，所提方法的F1-score分别达到0.921和0.861，高于CrossSpot、fBox和EvilCohort算法，与M-Zoom算法的0.899和0.898相近，但是所提方法的平均运行时间和内存消耗峰值均小于M-Zoom算法；在真实数据集上，所提方法的F1-score达到0.550，高于fBox和EvilCohort算法，与M-Zoom算法的0.529相近。实验结果表明，所提方法能较好地应用于现阶段的银行反电信诈骗业务，且非常适合于实际应用中的大规模数据集。     

Yet another generation of LALR parsers for regular right part grammars

In this paper we introduce two methods for building LALR parsers for regular right part grammars (RRPGs). Both methods build a parser directly from a grammar, require no extra state or data structure, and can deal with all LALR RRPGs. The first method is quite simple. For almost all LALR RRPGs, including the majority of grammars with stacking conflicts, parsing actions are similar to those of LALR parsers for usual context free grammars. No extra action is required to recognize a handle in this case. For other LALR RRPGs, the right hand side of a production is checked to recognize a handle. The second method does not require checking of the right hand side of a production to recognize a handle. Instead, it records the number of conflicts in LR items and in the stack. Unlike previous methods, our method needs no extra data structure. Received: 23 September 1998 / 16 March 2001     

Yet another proof of the cascade decomposition theorem for finite automata

We give here a short proof that each finite automaton can be built as a cascade of permutation automata and identity-reset automata.This paper was presented at the Conference on the Algebraic Theory of Machines, Languages and Semigroups, 29 August–8 September 1966, at Asilomar, California, organized by the Krohn-Rhodes Research Institute.     

Yet another tutorial of disturbance observer: robust stabilization and recovery of nominal performance

This paper presents a tutorial-style review on the recent results about the disturbance observer (DOB) in view of robust stabilization and recovery of the nominal performance. The analysis is based on the case when the bandwidth of Q-filter is large, and it is explained in a pedagogical manner that, even in the presence of plant uncertainties and disturbances, the behavior of real uncertain plant can be made almost similar to that of disturbance-free nominal system both in the transient and in the steady-state. The conventional DOB is interpreted in a new perspective, and its restrictions and extensions are discussed.