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2023-02-02
Tian, Yingchi, Xiao, Shiwu.  2022.  Parameter sensitivity analysis and adjustment for subsynchronous oscillation stability of doubly-fed wind farms with static var generator. 2022 7th International Conference on Intelligent Computing and Signal Processing (ICSP). :215–219.
The interaction between the transmission system of doubly-fed wind farms and the power grid and the stability of the system have always been widely concerned at home and abroad. In recent years, wind farms have basically installed static var generator (SVG) to improve voltage stability. Therefore, this paper mainly studies the subsynchronous oscillation (SSO) problem in the grid-connected grid-connected doubly-fed wind farm with static var generators. Firstly based on impedance analysis, the sequence impedance model of the doubly-fed induction generator and the static var generator is established by the method. Then, based on the stability criterion of Bode plot and time domain simulation, the influence of the access of the static var generator on the SSO of the system is analyzed. Finally, the sensitivity analysis of the main parameters of the doubly-fed induction generator and the static var generator is carried out. The results show that the highest sensitivity is the proportional gain parameter of the doubly-fed induction generator current inner loop, and its value should be reduced to reduce the risk of SSO of the system.
2022-09-20
Abuah, Chike, Silence, Alex, Darais, David, Near, Joseph P..  2021.  DDUO: General-Purpose Dynamic Analysis for Differential Privacy. 2021 IEEE 34th Computer Security Foundations Symposium (CSF). :1—15.
Differential privacy enables general statistical analysis of data with formal guarantees of privacy protection at the individual level. Tools that assist data analysts with utilizing differential privacy have frequently taken the form of programming languages and libraries. However, many existing programming languages designed for compositional verification of differential privacy impose significant burden on the programmer (in the form of complex type annotations). Supplementary library support for privacy analysis built on top of existing general-purpose languages has been more usable, but incapable of pervasive end-to-end enforcement of sensitivity analysis and privacy composition. We introduce DDuo, a dynamic analysis for enforcing differential privacy. DDuo is usable by non-experts: its analysis is automatic and it requires no additional type annotations. DDuo can be implemented as a library for existing programming languages; we present a reference implementation in Python which features moderate runtime overheads on realistic workloads. We include support for several data types, distance metrics and operations which are commonly used in modern machine learning programs. We also provide initial support for tracking the sensitivity of data transformations in popular Python libraries for data analysis. We formalize the novel core of the DDuo system and prove it sound for sensitivity analysis via a logical relation for metric preservation. We also illustrate DDuo's usability and flexibility through various case studies which implement state-of-the-art machine learning algorithms.
2022-07-29
Saxena, Nikhil, Narayanan, Ram Venkat, Meka, Juneet Kumar, Vemuri, Ranga.  2021.  SRTLock: A Sensitivity Resilient Two-Tier Logic Encryption Scheme. 2021 IEEE International Symposium on Smart Electronic Systems (iSES). :389—394.
Logic encryption is a method to improve hardware security by inserting key gates on carefully selected signals in a logic design. Various logic encryption schemes have been proposed in the past decade. Many attack methods to thwart these logic locking schemes have also emerged. The satisfiability (SAT) attack can recover correct keys for many logic obfuscation methods. Recently proposed sensitivity analysis attack can decrypt stripped functionality based logic encryption schemes. This article presents a new encryption scheme named SRTLock, which is resilient against both attacks. SRTLock method first generates 0-injection circuits and encrypts the functionality of these nodes with the key inputs. In the next step, these values are used to control the sensitivity of the functionally stripped output for specific input patterns. The resultant locked circuit is resilient against the SAT and sensitivity analysis attacks. Experimental results demonstrating this on several attacks using standard benchmark circuits are presented.
2021-12-21
Zhang, Fengqing, Jiang, Xiaoning.  2021.  The Zero Trust Security Platform for Data Trusteeship. 2021 4th International Conference on Advanced Electronic Materials, Computers and Software Engineering (AEMCSE). :1014–1017.
Cloud storage is a low-cost and convenient storage method, but the nature of cloud storage determines the existence of security risks for data uploaded by users. In order to ensure the security of users' data in third-party cloud platforms, a zero trust security platform for data trusteeship is proposed. The platform introduces the concept of zero trust, which meets the needs of users to upload sensitive data to untrusted third-party cloud platforms by implementing multiple functional modules such as sensitivity analysis service, cipher index service, attribute encryption service.
2021-01-28
Santos, W., Sousa, G., Prata, P., Ferrão, M. E..  2020.  Data Anonymization: K-anonymity Sensitivity Analysis. 2020 15th Iberian Conference on Information Systems and Technologies (CISTI). :1—6.

These days the digitization process is everywhere, spreading also across central governments and local authorities. It is hoped that, using open government data for scientific research purposes, the public good and social justice might be enhanced. Taking into account the European General Data Protection Regulation recently adopted, the big challenge in Portugal and other European countries, is how to provide the right balance between personal data privacy and data value for research. This work presents a sensitivity study of data anonymization procedure applied to a real open government data available from the Brazilian higher education evaluation system. The ARX k-anonymization algorithm, with and without generalization of some research value variables, was performed. The analysis of the amount of data / information lost and the risk of re-identification suggest that the anonymization process may lead to the under-representation of minorities and sociodemographic disadvantaged groups. It will enable scientists to improve the balance among risk, data usability, and contributions for the public good policies and practices.

2020-02-17
Leite, Leonardo H. M., do Couto Boaventura, Wallace, de Errico, Luciano, Machado Alessi, Pedro.  2019.  Self-Healing in Distribution Grids Supported by Photovoltaic Dispersed Generation in a Voltage Regulation Perspective. 2019 IEEE PES Innovative Smart Grid Technologies Conference - Latin America (ISGT Latin America). :1–6.
Distributed Generation Photovoltaic Systems -DGPV - connected to the power distribution grid through electronic inverters can contribute, in an aggregate scenario, to the performance of several power system control functions, notably in self-healing and voltage regulation along a distribution feeder. This paper proposes the use of an optimization method for voltage regulation, focused on reactive power injection control, based on a comprehensive architecture model that coordinates multiple photovoltaic distributed sources to support grid reconfiguration after self-healing action. A sensitivity analysis regarding the performance of voltage regulation, based on a co-simulation of PSCAD and MatLab, shows the effectiveness of using dispersed generation sources to assist grid reconfiguration after disturbances caused by severe faults.
2018-09-12
Chhokra, Ajay, Kulkarni, Amogh, Hasan, Saqib, Dubey, Abhishek, Mahadevan, Nagabhushan, Karsai, Gabor.  2017.  A Systematic Approach of Identifying Optimal Load Control Actions for Arresting Cascading Failures in Power Systems. Proceedings of the 2Nd Workshop on Cyber-Physical Security and Resilience in Smart Grids. :41–46.
Cascading outages in power networks cause blackouts which lead to huge economic and social consequences. The traditional form of load shedding is avoidable in many cases by identifying optimal load control actions. However, if there is a change in the system topology (adding or removing loads, lines etc), the calculations have to be performed again. This paper addresses this problem by providing a workflow that 1) generates system models from IEEE CDF specifications, 2) identifies a collection of blackout causing contingencies, 3) dynamically sets up an optimization problem, and 4) generates a table of mitigation strategies in terms of minimal load curtailment. We demonstrate the applicability of our proposed methodology by finding load curtailment actions for N-k contingencies (k = 1, 2, 3) in IEEE 14 Bus system.
2018-07-06
Zhang, F., Chan, P. P. K., Tang, T. Q..  2015.  L-GEM based robust learning against poisoning attack. 2015 International Conference on Wavelet Analysis and Pattern Recognition (ICWAPR). :175–178.

Poisoning attack in which an adversary misleads the learning process by manipulating its training set significantly affect the performance of classifiers in security applications. This paper proposed a robust learning method which reduces the influences of attack samples on learning. The sensitivity, defined as the fluctuation of the output with small perturbation of the input, in Localized Generalization Error Model (L-GEM) is measured for each training sample. The classifier's output on attack samples may be sensitive and inaccurate since these samples are different from other untainted samples. An import score is assigned to each sample according to its localized generalization error bound. The classifier is trained using a new training set obtained by resampling the samples according to their importance scores. RBFNN is applied as the classifier in experimental evaluation. The proposed model outperforms than the traditional one under the well-known label flip poisoning attacks including nearest-first and farthest-first flips attack.

2017-12-04
Balluff, M., Naumoski, H., Hameyer, K..  2016.  Sensitivity analysis on tolerance induced torque fluctuation of a synchronous machine. 2016 6th International Electric Drives Production Conference (EDPC). :128–134.

The manufacturing process of electrical machines influences the geometric dimensions and material properties, e.g. the yoke thickness. These influences occur by statistical variation as manufacturing tolerances. The effect of these tolerances and their potential impact on the mechanical torque output is not fully studied up to now. This paper conducts a sensitivity analysis for geometric and material parameters. For the general approach these parameters are varied uniformly in a range of 10 %. Two dimensional finite element analysis is used to simulate the influences at three characteristic operating points. The studied object is an internal permanent magnet machine in the 100 kW range used for hybrid drive applications. The results show a significant dependency on the rotational speed. The general validity is studied by using boundary condition variations and two further machine designs. This procedure offers the comparison of matching qualitative results for small quantitative deviations. For detecting the impact of the manufacturing process realistic tolerance ranges are used. This investigation identifies the airgap and magnet remanence induction as the main parameters for potential torque fluctuation.

2017-03-07
Alimolaei, S..  2015.  An intelligent system for user behavior detection in Internet Banking. 2015 4th Iranian Joint Congress on Fuzzy and Intelligent Systems (CFIS). :1–5.

Security and making trust is the first step toward development in both real and virtual societies. Internet-based development is inevitable. Increasing penetration of technology in the internet banking and its effectiveness in contributing to banking profitability and prosperity requires that satisfied customers turn into loyal customers. Currently, a large number of cyber attacks have been focused on online banking systems, and these attacks are considered as a significant security threat. Banks or customers might become the victim of the most complicated financial crime, namely internet fraud. This study has developed an intelligent system that enables detecting the user's abnormal behavior in online banking. Since the user's behavior is associated with uncertainty, the system has been developed based on the fuzzy theory, This enables it to identify user behaviors and categorize suspicious behaviors with various levels of intensity. The performance of the fuzzy expert system has been evaluated using an receiver operating characteristic curve, which provides the accuracy of 94%. This expert system is optimistic to be used for improving e-banking services security and quality.

2016-11-15
2015-05-06
Musgrove, J., Cukic, B., Cortellessa, V..  2014.  Proactive Model-Based Performance Analysis and Security Tradeoffs in a Complex System. High-Assurance Systems Engineering (HASE), 2014 IEEE 15th International Symposium on. :211-215.

Application domains in which early performance evaluation is needed are becoming more complex. In addition to traditional measures of complexity due, for example, to the number of components, their interactions, complicated control coordination and schemes, emerging applications may require adaptive response and reconfiguration the impact of externally observable (security) parameters. In this paper we introduce an approach for effective modeling and analysis of performance and security tradeoffs. The approach identifies a suitable allocation of resources that meet performance requirements, while maximizing measurable security effects. We demonstrate this approach through the analysis of performance sensitivity of a Border Inspection Management System (BIMS) with changing security mechanisms (e.g. biometric system parameters for passenger identification). The final result is a model-based approach that allows us to take decisions about BIMS performance and security mechanisms on the basis of rates of traveler arrivals and traveler identification security guarantees. We describe the experience gained when applying this approach to daily flight arrival schedule of a real airport.

2015-05-05
Visala, K., Keating, A., Khan, R.H..  2014.  Models and tools for the high-level simulation of a name-based interdomain routing architecture. Computer Communications Workshops (INFOCOM WKSHPS), 2014 IEEE Conference on. :55-60.

The deployment and operation of global network architectures can exhibit complex, dynamic behavior and the comprehensive validation of their properties, without actually building and running the systems, can only be achieved with the help of simulations. Packet-level models are not feasible in the Internet scale, but we are still interested in the phenomena that emerge when the systems are run in their intended environment. We argue for the high-level simulation methodology and introduce a simulation environment based on aggregate models built on state-of-the-art datasets available while respecting invariants observed in measurements. The models developed are aimed at studying a clean slate name-based interdomain routing architecture and provide an abundance of parameters for sensitivity analysis and a modular design with a balanced level of detail in different aspects of the model. In addition to introducing several reusable models for traffic, topology, and deployment, we report our experiences in using the high-level simulation approach and potential pitfalls related to it.
 

2015-04-30
El Masri, A., Wechsler, H., Likarish, P., Kang, B.B..  2014.  Identifying users with application-specific command streams. Privacy, Security and Trust (PST), 2014 Twelfth Annual International Conference on. :232-238.

This paper proposes and describes an active authentication model based on user profiles built from user-issued commands when interacting with GUI-based application. Previous behavioral models derived from user issued commands were limited to analyzing the user's interaction with the *Nix (Linux or Unix) command shell program. Human-computer interaction (HCI) research has explored the idea of building users profiles based on their behavioral patterns when interacting with such graphical interfaces. It did so by analyzing the user's keystroke and/or mouse dynamics. However, none had explored the idea of creating profiles by capturing users' usage characteristics when interacting with a specific application beyond how a user strikes the keyboard or moves the mouse across the screen. We obtain and utilize a dataset of user command streams collected from working with Microsoft (MS) Word to serve as a test bed. User profiles are first built using MS Word commands and identification takes place using machine learning algorithms. Best performance in terms of both accuracy and Area under the Curve (AUC) for Receiver Operating Characteristic (ROC) curve is reported using Random Forests (RF) and AdaBoost with random forests.