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Data mining as a tool in privacy-preserving data publishing

ABSTRACT

Many databases contain data about individuals that are valuable for research, marketing, and decision making. Sharing or publishing data about individuals is however prone to privacy attacks, breaches, and disclosures. The concern here is about individuals’ privacy-keeping the sensitive information about individuals private to them. Data mining in this setting has been shown to be a powerful tool to breach privacy and make disclosures. In contrast, data mining can be also used in practice to aid data owners in their decision on how to share and publish their databases. We present and discuss the role and uses of data mining in these scenarios and also briefly discuss other approaches to private data analysis.

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Self-Spectre, Write-Execute and the Hidden State

Abstract

The recent Meltdown and Spectre vulnerabilities have highlighted a very present and real threat in the on-chip memory cache units which can ultimately provide a hidden state, albeit only readable via memory timing instructions [Kocher, P.—Genkin, D.— Gruss, D.— Haas, W.—Hamburg, M.—Lipp, M.–Mangard, S.—Prescher, T.—Schwarz, M.—Yarom, Y.: Spectre attacks: Exploiting speculative execution, CoRR, abs/1801.01203, 2018]. Yet the exploits, although having some complexity and slowness, are demonstrably reliable on nearly all processors produced for the last two decades.

Moving out from looking at this strictly as a means of reading protected memory, as the large microprocessor companies move to close this security vulnerability, an interesting question arises. Could the inherent design of the processor give the ability to hide arbitrary calculations in this speculative and parallel side channel? Without even using protected memory and exploiting the vulnerability, as has been the focus, there could very well be a whole class of techniques which exploit the side-channel. It could be done in a way which would be largely un-preventable behavior as the technology would start to become self-defeating or require a more complicated and expensive on-chip cache memory system to properly post-speculatively clean itself. And the ability to train the branch predictor to incorrectly speculatively behave is almost certain given hardware limitations, andthusprovidesexactly this pathway.

A novel approach looks at just how much computation can be done speculatively with a result store via indirect reads and available through the memory cache. A multi-threaded approach can allow a multi-stage computation pipeline where each computation is passed to a read-out thread and then to the next computation thread [Swanson, S.—McDowell, L. K.—Swift, M. M.—Eggers, S. J.–Levy H. M.: An evaluation of speculative instruction execution on simultaneous multithreaded processors, ACM Trans. Comput. Syst. 21 (2003), 314–340].

Through channels like this, an application can surreptitiously make arbitrary calculations, or even leak data without any standard tracing tools being capable of monitoring the subtle changes. Like a variation of the famous physics Heisenberg uncertainty principle, even a tool capable of reading the cache states would not only be incredibly inefficient, but thereby tamper with and modify the state. Tools like in-circuit emulators, or specially designed cache emulators would be needed to unmask the speculative reads, and it is further difficult to visualize with a linear time-line.

Specifically, the AES and RSA algorithms will be studied with respect to these ideas, looking at success rates for various calculation batches with speculative execution, while having a summary view to see the rather severe performance penalties for using such methods.

Either approaches could provide for strong white-box cryptography when considering a binary, non-source code form. In terms of white-box methods, both could be significantly challenging to locate or deduce the inner workings of the code. Further, both methods can easily surreptitiously leak or hide data within shared memory in a seemingly innocuous manner.

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Tabu Cryptanalysis of VMPC Stream Cipher

REFERENCES [1] ANTAL, E.—ELIÁŠ, M.: Evolutionary computation in cryptanalysis of classical ciphers , Tatra Mt. Math. Publ. 70 (2017), 179–197. [2] BHATEJA, A. K.—BHATEJA, A.—CHAUDHURY, S.—SAXENA, P. K.: Cryptanalysis of Vigenère cipher using Cuckoo search , Appl. Soft Comput. 26 (2015), 315–324. [3] DWORAK, K.—BORYCZKA, U.: Genetic algorithm as optimization tool for differential cryptanalysis of DES6 . In: Computational Collective Intelligence: 9th International Conference, ICCCI 2017, Nicosia, Cyprus, September 27-29, 2017, Proceedings

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Cryptanalysis of the Columnar Transposition Using Meta-Heuristics

REFERENCES [1] ANTAL, E.: Modern Cryptanalysis of Classical Ciphers . PhD. Thesis, STU in Bratislave, 2017. (In Slovak) [2] ANTAL, E.—ELIÁŠ, M.: Evolutionary Computation in cryptanalysis of classical ciphers , Tatra Mt. Math. Publ. 70 (2017), 179–197. [3] ANTAL, E.—GROŠEK, O.—HORAK, P.: On a mnemonic construction of permutations , J. Math Cryptology. 11 (2017), no. 1, 45–53. [4] BANKS, M. J.: A Search-Based Tool for the Automated Cryptanalysis of Classical Ciphers . The University of York, Department of Computer Science, May, 2008

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Evaluation of the Patients’ Satisfaction with Psychiatric Health Care Services with an Adapted PIPEQ-OS Tool

Abstract

Until now, the assessment of health care services provided by psychiatric institutions in Latvia has not been carried out and questionnaires to provide assessment from the patient’s perspective have not been adapted. For this study, a questionnaire that has been validated and successfully employed for several years in Norway was chosen to assess patients’ experience and in a psychiatric inpatient setting. The aim of the study was to determine patients’ satisfaction with the quality of mental health care services in Latvia in the subacute inpatient psychiatric ward in Rīga, adapting during this process the PIPEQ-OS (Psychiatric Inpatient Patient Experience Questionnaire) tool in Latvia. The pilot quantitative study was conducted from June 2016 till February 2017. In the study, an anonymous patient self-assessment questionnaire PIPEQ-OS containing 21 questions was used. During the adaptation process, the questionnaire was translated from English into Latvian and Russian and backwards. The quality and compliance of the translation was subsequently tested in cognitive interviews. During the study, 297 patients were discharged from the unit, and 231 of them completed the questionnaire. 12% of the completed questionnaires were not included in data processing due to being incorrectly filled in. Cognitive interviews with 20 patients were carried out; the average length of an interview was 15 minutes. Overall, the translation of the questionnaire proved to be relevant to the research theme. The subsequent factor analysis revealed three significant factors that reached the Cronbach’s alpha index of 0.7. Further studies using socio-demographic data and based on various inpatient units as well as the comparison of satisfaction indicators across different diagnostic groups are needed.

Open access
On the New Solutions of the Conformable Time Fractional Generalized Hirota-Satsuma Coupled KdV System

tool for solving certain classes of non-linear PDEs, Mathe- matical methods in the applied sciences, 28.17, (2005), 2031-2035 [20] W. Maliet, The tanh method: a tool for solving certain classes of nonlinear evolution and wave equations, Journal of Computational and Applied Mathematics, 164, (2004), 529-541 [21] S.J. Liao, Beyond Perturbation: Introduction to the Homotopy Analysis Method, Chapman and Hall/CRC Press, Boca Raton, 2003.

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From Multicriterial Data Analysis Up to the Exclusive Contract

.—KETTER, W.: Agentassisted supply chain management: Analysis and lessons learned , Decision Support Systems 57 (2014), no. 1, 274–284; https://www.sciencedirect.com/science/article/pii/S0167923613002340 [14] HAIR, J.—ANDERSON, R.—TATHAM, R.—BLACK, W.: Multivariate Data Analysis . Saddle River, Prentice Hall, New Jersey, 1995. [15] IMERI, S.—SHAHZAD, K.—TAKALA, J.—LIU, Y.—SILLANPÄÄ, I.—ALI, T.: Evaluation and selection process of suppliers through analytical framework: An empirical evidence of evaluation tool , Management and Production Engineering Review

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The sharp version of a strongly starlikeness condition

Abstract

In this paper we give the best form of a strongly starlikeness condition. Some consequences of this result are deduced. The basic tool of the research is the method of differential subordinations.

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Generalized CreditRisk+ model and applications

Abstract

In the paper we give a mathematical overview of the CreditRisk+ model as a tool used for calculating credit risk in a portfolio of debts and suggest some other applications of the same method of analysis.

Open access
On two-scale convergence and periodic unfolding

Abstract

Two-scale convergence is an important tool in homogenization theory. The contribution deals with various primary and adjoint (based on unfolding) approaches to the two-scale convergence and their pro-and-con.

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