Resilience Against Sensor Deception Attacks at the Supervisory Control Layer of Cyber-Physical Systems: A Discrete Event Systems Approach

Cyber-Physical Systems (CPS) are already ubiquitous in our society and include medical devices, (semi-)autonomous vehicles, and smart grids. However, their security aspects were only recently incorporated into their design process, mainly in response to catastrophic incidents caused by cyber-attacks on CPS. The Stuxnet attack that successfully damaged a nuclear facility, the Maroochy water breach that released millions of gallons of untreated water, the assault on power plants in Brazil that disrupted the distribution of energy in many cities, and the intrusion demonstration that stopped the engine of a 2014 Jeep Cherokee in the middle of a highway are examples of well-publicized cyber-attacks on CPS. There is now a critical need to provide techniques for analyzing the behavior of CPS while under attack and to synthesize attack-resilient CPS. In this dissertation, we address CPS under the influence of an important class of attacks called sensor deception attacks, in which an attacker hijacks sensor readings to inflict damage to CPS. The formalism of regular languages and their finite-state automata representations is used to capture the dynamics of CPS and their attackers, thereby allowing us to leverage the theory of supervisory control of discrete event systems to pose our investigations. First, we focus on developing a supervisory control framework under sensor deception attacks. We focus on two questions: (1) Can we automatically find sensor deception attacks that damage a given CPS? and (2) Can we design a secure-by-construction CPS against sensor deception attacks? Answering these two questions is the main contribution of this dissertation. In the first part of the dissertation, using techniques from the fields of graph games and Markov decision processes, we develop algorithms for synthesizing sensor deception attacks in both qualitative and quantitative settings. Graph games provide the means of synthesizing sensor deception attacks that might damage the given CPS. In a second step, equipped with stochastic information about the CPS, we can leverage Markov decision processes to synthesize attacks with the highest likelihood of damage. In the second part of the dissertation, we tackle the problem of designing secure-by-construction CPS. We provide two different methodologies to design such CPS, in which there exists a trade-off between flexibility on selecting different designs and computational complexity of the methods. The first method is developed based on supervisory control theory, and it provides a computationally efficient way of designing secure CPS. Alternatively, a graph-game method is presented as a second solution for this investigated problem. The graph-game method grants flexible selection of the CPS at the cost of computational complexity. The first method finds one robust supervisor, whereas the second method provides a structure in which all robust supervisors are included. Overall, this dissertation provides a comprehensive set of algorithmic techniques to analyze and mitigate sensor deception attacks at the supervisory layer of cyber-physical control systems.PHDElectrical and Computer EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/166117/1/romulo_1.pd

Need of dental prosthesis in older people and the offer of specialized care in the unified health system, Brazil

Objective: To analyze the offer of dental prosthesis by Centers of Dental Specialties (CEO) considering the need by individuals aged 65-74 years in state capitals and other regions of the country. Material and Methods: The study was conducted with data from the external evaluation of the Improving Access and Quality Program (AVE/PMAQ CEO) and with data from the SBBRASIL 2010 project. AVE / PMAQ CEO is an evaluative investigation using a cross-sectional research design, performed in all CEOs of Brazil, totaling 932 services evaluated. The analysis of data and distribution of CEOs that offered dental prosthesis was described by maps, using TabWin (DATASUS) and quantitative description of the following variables: need for total and partial dentures, CEO, Regional Prosthodontic Laboratories (RLDP), average monthly number of delivered prostheses and the proportion of capitals with RLDP, number of CEOs, RLDP and prostheses delivered per 100,000 inhabitants in state capitals and other regions. Results: Of the 5,570 municipalities in the country, 780 have CEO, mainly located on municipalities with larger populations. Most CEOs were located in the northeastern (38.3%) and southeastern regions of Brazil (36.2%) with the northern and mid-western regions presenting the lowest absolute number of units. Low offer of prostheses was observed, considering the high need of dentures, as well as an unequal distribution among Brazilian regions. A high percentage of older adults aged 65-74 years require total (74.6%) or partial (99.8%) prosthetic rehabilitation, more critical situation is observed in the northern and northeastern regions. Conclusion: The provision of dental services in CEOs is still limited and unevenly distributed, especially for PPR, compromising the universality and integrality of oral health care

Investigating Robustness in Cyber-Physical Systems: Specification-Centric Analysis in the face of System Deviations

The adoption of cyber-physical systems (CPS) is on the rise in complex physical environments, encompassing domains such as autonomous vehicles, the Internet of Things (IoT), and smart cities. A critical attribute of CPS is robustness, denoting its capacity to operate safely despite potential disruptions and uncertainties in the operating environment. This paper proposes a novel specification-based robustness, which characterizes the effectiveness of a controller in meeting a specified system requirement, articulated through Signal Temporal Logic (STL) while accounting for possible deviations in the system. This paper also proposes the robustness falsification problem based on the definition, which involves identifying minor deviations capable of violating the specified requirement. We present an innovative two-layer simulation-based analysis framework designed to identify subtle robustness violations. To assess our methodology, we devise a series of benchmark problems wherein system parameters can be adjusted to emulate various forms of uncertainties and disturbances. Initial evaluations indicate that our falsification approach proficiently identifies robustness violations, providing valuable insights for comparing robustness between conventional and reinforcement learning (RL)-based controllersComment: 12 page

Physical activity level and physical performance in the 6-minute walk test in women with fibromyalgia

AbstractIntroductionFibromyalgia (FM) is a chronic pain condition that causes impaired functional capacity, possibly through the adoption of sedentary behaviour. However, little is known regarding physical activity level and its relationship with physical performance in women with FM.ObjectivesTo compare physical activity level, assessed using the International Physical Activity Questionnaire (IPAQ), and physical performance, measured using the six-minute walk test (6MWT), in women with and without FM and to examine the possible relationships between physical activity level and physical performance in both groups.MethodsThe study included 30 women diagnosed with FM (patients) and 28 healthy women (controls) who answered the IPAQ and performed the 6MWT.ResultsPatients and controls self-reported similar physical activity level, considering both the total score and all IPAQ subcomponents (P>0.05). However, the FM patients had worse physical performance in the 6MWT (patients, 441.8±84.1 m vs. controls, 523.9±80.3 m; P<0.01). There were no relationships between the distance walked in the 6MWT and the IPAQ variables for the control group. However, the distance walked by patients in the test showed a significant correlation (P<0.05) with the total score and the subcomponents transport, household activities, and physical activities of moderate intensity in the IPAQ.ConclusionsWomen with FM had physical activity levels similar to women without FM but exhibited worse physical performance. This functional impairment may be related to the lifestyle adopted because there was a relationship between physical activity level and physical performance in those patients

Consumo de álcool em adolescentes de uma escola da rede publica de ensino do município de Ponta Grossa (PR)

Analisar o alcoolismo em adolescentes de uma escola da rede publica de ensino. Participaram do estudo 63 estudantes de escola da rede publica de ensino do município de Ponta Grossa (PR) (39 do sexo feminino e 24 do sexo masculino). O consumo de álcool foi mensurado pelo AUDIT e a consistência interna atraves do coeficiente Alfa de Cronbach. Para analise do consumo de álcool recorreu-se a estatística descritiva e o teste de Qui-Quadrado para verificar as possíveis associates do álcool ao sexo. Os resultados demonstram que o consumo de álcool foi de baixo risco e não foram encontradas associates entre o alcoolismo e o sexo para esta pesquisa

Investigation of 15q11-q13, 16p11.2 and 22q13 CNVs in Autism Spectrum Disorder Brazilian Individuals with and without Epilepsy

Copy number variations (CNVs) are an important cause of ASD and those located at 15q11-q13, 16p11.2 and 22q13 have been reported as the most frequent. These CNVs exhibit variable clinical expressivity and those at 15q11-q13 and 16p11.2 also show incomplete penetrance. In the present work, through multiplex ligation-dependent probe amplification (MLPA) analysis of 531 ethnically admixed ASD-affected Brazilian individuals, we found that the combined prevalence of the 15q11-q13, 16p11.2 and 22q13 CNVs is 2.1% (11/531). Parental origin could be determined in 8 of the affected individuals, and revealed that 4 of the CNVs represent de novo events. Based on CNV prediction analysis from genome-wide SNP arrays, the size of those CNVs ranged from 206 kb to 2.27 Mb and those at 15q11-q13 were limited to the 15q13.3 region. In addition, this analysis also revealed 6 additional CNVs in 5 out of 11 affected individuals. Finally, we observed that the combined prevalence of CNVs at 15q13.3 and 22q13 in ASD-affected individuals with epilepsy (6.4%) was higher than that in ASD-affected individuals without epilepsy (1.3%; p<0.014). Therefore, our data show that the prevalence of CNVs at 15q13.3, 16p11.2 and 22q13 in Brazilian ASD-affected individuals is comparable to that estimated for ASD-affected individuals of pure or predominant European ancestry. Also, it suggests that the likelihood of a greater number of positive MLPA results might be found for the 15q13.3 and 22q13 regions by prioritizing ASD-affected individuals with epilepsy.Support was provided by FAPESP-INCT - grant number: 2008/57899-7; FAPESP-CEPID - grant number: 2013/08028-1; CNPq [http://www.fapesp.br/]. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript