Improving RO PUF design using frequency distribution characteristics

A Physical Unclonable Function (PUF) can be used to provide authentication of devices by producing die-unique responses. In PUFs based on ring oscillators (ROs) the responses are derived from the oscillation frequencies of the ROs. However, RO PUFs can be vulnerable to attack due to the frequency distribution characteristics of the RO arrays. In this letter, in order to improve the design of RO PUFs for FPGA devices, the frequencies of RO arrays implemented on a large number of FPGA chips are statistically analyzed. Three RO frequency distribution (ROFD) characteristics, which can be used to improve the design of RO PUFs are observed and discussed.

RO PUF Design in FPGAs with new comparison strategies

A Physical Unclonable Function (PUF) can be used to provide authentication of devices by producing die-unique responses. In PUFs based on ring oscillators (ROs), the responses are derived from the oscillation frequencies of the ROs. However, RO PUFs can be vulnerable to attack due to the frequency distribution characteristics of the RO arrays. In this paper, in order to improve the design of RO PUFs for FPGA devices, the frequencies of RO arrays implemented on a large number of FPGA chips are statistically analyzed. Three RO frequency distribution (ROFD) characteristics are observed and discussed. Based on these ROFD characteristics, two RO comparison strategies are proposed that can be used to improve the design of RO PUFs. It is found that the symmetrical RO comparison strategy has the highest entropy density.

Ecological and economic consequences of hypoxia: Topic 2 Report for the Integrated Assessment on Hypoxia in the Gulf of Mexico

In this report we have attempted to evaluate the ecological and economic consequences of hypoxia in the northern Gulf of Mexico. Although our initial approach was to rely on published accounts, we quickly realized that the body of published literature deahng with hypoxia was limited, and we would have to conduct our own exploratory analysis of existing Gulf data, or rely on published accounts from other systems to infer possible or potential effects of hypoxia. For the economic analysis, we developed a conceptual model of how hypoxia-related impacts could affect fisheries. Our model included both supply and demand components. The supply model had two components: (1) a physical production function for fish or shrimp, and (2) the cost of fishing. If hypoxia causes the cost of a unit of fishing effort to change, then this will result in a shift in supply. The demand model considered how hypoxia might affect the quality of landed fish or shrimp. In particular, the market value per pound is lower for small shrimp than for large shrimp. Given the limitations of the ecological assessment, the shallow continental shelf area affected by hypoxia does show signs of hypoxia-related stress. While current ecological conditions are a response to a variety of stressors, the effects of hypoxia are most obvious in the benthos that experience mortality, elimination of larger long-lived species, and a shifting of productivity to nonhypoxic periods (energy pulsing). What is not known is whether hypoxia leads to higher productivity during productive periods, or simply to a reduction of productivity during oxygen-stressed periods. The economic assessment based on fisheries data, however, failed to detect effects attributable to hypoxia. Overall, fisheries landings statistics for at least the last few decades have been relatively constant. The failure to identify clear hypoxic effects in the fisheries statistics does not necessarily mean that they are absent. There are several possibilities: (1) hypoxic effects are small relative to the overall variability in the data sets evaluated; (2) the data and the power of the analyses are not adequate; and (3) currently there are no hypoxic effects on fisheries. Lack of identified hypoxic effects in available fisheries data does not imply that effects would not occur should conditions worsen. Experience with other hypoxic zones around the globe shows that both ecological and fisheries effects become progressively more severe as hypoxia increases. Several large systems around the globe have suffered serious ecological and economic consequences from seasonal summertime hypoxia; most notable are the Kattegat and Black Sea. The consequences range from localized loss of catch and recruitment failure to complete system-wide loss of fishery species. If experiences in other systems are applicable to the Gulf of Mexico, then in the face of worsening hypoxic conditions, at some point fisheries and other species will decline, perhaps precipitously.

A unique and robust single slice FPGA identification generator

In this paper, a new field-programmable gate array (FPGA) identification generator circuit is introduced based on physically unclonable function (PUF) technology. The new identification generator is able to convert flip-flop delay path variations to unique n-bit digital identifiers (IDs), while requiring only a single slice per ID bit by using 1-bit ID cells formed as hard-macros. An exemplary 128-bit identification generator is implemented on ten Xilinx Spartan-6 FPGA devices. Experimental results show an uniqueness of 48.52%, and reliability of 92.41% over a 25°C to 70°C temperature range and 10% fluctuation in supply voltage

Implementation Experiences from Smart Grid Security Applications and Outlook on Future Research

Experiences from smart grid cyber-security incidents in the past decade have raised questions on the applicability and effectiveness of security measures and protection mechanisms applied to the grid. In this chapter we focus on the security measures applied under real circumstances in today’s smart grid systems. Beginning from real world example implementations, we first review cyber-security facts that affected the electrical grid, from US blackout incidents, to the Dragonfly cyber-espionage campaign currently focusing on US and European energy firms. Provided a real world setting, we give information related to energy management of a smart grid looking also in the optimization techniques that power control engineers perform into the grid components. We examine the application of various security tools in smart grid systems, such as intrusion detection systems, smart meter authentication and key management using Physical Unclonable Functions, security analytics and resilient control algorithms. Furthermore we present evaluation use cases of security tools applied on smart grid infrastructure test-beds that could be proved important prior to their application in the real grid, describing a smart grid intrusion detection system application and security analytics results. Anticipated experimental results from the use-cases and conclusions about the successful transitions of security measures to real world smart grid operations will be presented at the end of this chapter.

PUF-based secure checker protocol for Networked RFID Systems

Radio Frequency Identification (RFID) system is anemerging technology for automating object identification. TheNetworked RFID System (NRS) is a component of a distributedobject identification network which facilitates automated supplychain management. It also makes the Internet of Things (IoT)concept a reality. To increase the business feasibility of NRSimplementation, the system should be able to ensure the visibilityand traceability of the object throughout the chain using achecker protocol. By doing so, the protocol will check thegenuineness of the object and the genuineness of the object’sprevious travel path on-site. While doing so, the protocol needs toensure the security requirement of the system. To this end, wepropose a secure checker protocol for NRS which will use a PUF(Physically Unclonable Function) and simple cryptographicprimitives. The protocol provides security (protect privacy of thepartners, injection of fake objects, non-repudiation, andunclonability), visibility and traceability for NRS. It is alsosuitable for passive tags.

Secure object tracking protocol for networked RFID systems

Networked systems have adapted Radio Frequency identification technology (RFID) to automate their business process. The Networked RFID Systems (NRS) has some unique characteristics which raise new privacy and security concerns for organizations and their NRS systems. The businesses are always having new realization of business needs using NRS. One of the most recent business realization of NRS implementation on large scale distributed systems (such as Internet of Things (IoT), supply chain) is to ensure visibility and traceability of the object throughout the chain. However, this requires assurance of security and privacy to ensure lawful business operation. In this paper, we are proposing a secure tracker protocol that will ensure not only visibility and traceability of the object but also genuineness of the object and its travel path on-site. The proposed protocol is using Physically Unclonable Function (PUF), Diffie-Hellman algorithm and simple cryptographic primitives to protect privacy of the partners, injection of fake objects, non-repudiation, and unclonability. The tag only performs a simple mathematical computation (such as combination, PUF and division) that makes the proposed protocol suitable to passive tags. To verify our security claims, we performed experiment on Security Protocol Description Language (SPDL) model of the proposed protocol using automated claim verification tool Scyther. Our experiment not only verified our claims but also helped us to eliminate possible attacks identified by Scyther.

Secure object tracking protocol for the internet of things

In this paper, we propose a secure object tracking protocol to ensure the visibility and traceability of an object along the travel path to support the Internet of Things (IoT). The proposed protocol is based on radio frequency identification system for global unique identification of IoT objects. For ensuring secure object tracking, lightweight cryptographic primitives and physically unclonable function are used by the proposed protocol in tags. We evaluated the proposed protocol both quantitatively and qualitatively. In our experiment, we modeled the protocol using security protocol description language (SPDL) and simulated SPDL model using automated claim verification tool Scyther. The results show that the proposed protocol is more secure and requires less computation compared to existing similar protocols.

Repercussões psico-sociais da síndrome dos ovários policísticos: estudo quali-quantitativo

BACKGROUND: Polycystic ovary syndrame (PCOS) has been shown to cause a reduction in quality of life. Little is known on the psychosocial aspects associated with PCOS, especially on women s own experiences regarding the syndrome. Therefore, the aim of this study was to analyze the psychosocial impact of PCOS by measuring the health-related quality of life and exploring the women s own experiences of PCOS. METHODS: A two-phase model of combination of quantitative and qualitative research approaches was conducted, a crass-sectional survey to pravide quantitative data on the quality of life and a qualitative approach to understand the women s experience in relation to the PC OS sympt?ms. For the first phase, 109 women with PC OS and 104 healthy contrais were evaluated with the 36-item short-form health survey (SF-36). Additionally, semi-structured interviews (n=30) were conducted to facilitate in-depth exploration of PC OS women s experience. RESUL TS: PCOS patients showed significant reductions in almost ali SF-36 domains of quality of life when compared with healthy contrais (physical function 76.5:!:20.5 and 84.6:!:15.9, respectively; physical rale function 56.4:!:43.3 and 72.6:!:33.3; general health 55.2:!:21.0 and 62.5:!:17.2; vitality 49.6:!:21.3 and 55.3:!:21.3; social function 55.3:!:32.4 and 66.2:!:26.7; emotional rale function 34.2:!:39.7 and 52.9:!:38.2; mental health 50.6:!:22.8 and 59.2:!:20.2). Thematic analysis revealed reports of feeling abnormal , sadness, afraid and anxiety. These feelings were related to four symptoms commonly experienced by women with PCOS: excess hair grawth; irregular or absent menstruation, infertility and obesity. CONCLUSIONS: Polycystic ovary syndrame impacts women both physically and psychosocially. Owing to this, women with PCOS need not only medical treatment for. the reproductive, esthetic and metabolic repercussions, but also the care of a multidisciplinary team, since PCOS is not just a physical condition, but also an important psychosocial problem that affects various aspects of a woman s life

Início de ativação muscular de estabilizadores primários e a capacidade física para avaliar estabilização lombo-pélvica

Introduction: Due to the high incidence of low back pain without apparent cause, different approaches to evaluate the lumbar instability has been proposed, such as surface electromyography to determine pre-activation and the ability of lumbar stabilization through functional physical assessment. In this context, the objective of this study was to evaluate the early activation of the primary stabilizing muscles in subjects without low back pain, with different physical abilities function (CFF). Method: Study participants were 20 subjects with 19.8 ± 1.4 years, 55.7 ± 8.8 kilos, 1.66 ± 0.08 m, of both sexes. The subjects underwent six Tests Physical Function (TFF) and the Test of Fast Moving Flexion Arm (TMRFB) to capture the electromyographic activity of the lumbar multifidus muscles (LM) and internal oblique - lower fibers (HI). Were assigned weights for each functional test and the result of the physical capacity of the final functional subject ranged from 0 to 100%. In the analysis of TMRB was considered the onset time of activation between the ML and HI. Results: Regarding TFF 2 (10%) subjects were considered to have normal physical capacity, 6 (30%) with good physical ability and 12 (60%) with regular physical capacity or poor. As for TMRFB average values of initiation of muscle activation in 75% of subjects were within the limits to characterize the condition of pre-muscle activation. Conclusion:The results obtained in the TFF were low compared with the CFF of asymptomatic subjects evaluated. This fact does not mean that the condition of stabilization of the subject is appropriate. However, the results obtained in the electromyographic examination to suggest that 25% of asymptomatic subjects tested did not have a proper condition of lumbar stabilization.

Efeitos de um programa de exercício físico na capacidade funcional de idosos institucionalizados no Lar da 3ª idade Beiral: projeto de intervenção

Mestrado em Fisioterapia

Physical function and health-related quality of life of older adults undergoing hospital rehabilitation : how strong is the association?

The purpose of this research is to report preliminary empirical evidence regarding the association between common physical performance measures and health-related quality of life (HRQoL) of hospitalized older adults recovering from illness and injury. Frequently, these patients do not return to premorbid levels of independence and physical ability. Rehabilitation for this population often focuses on improving physical functioning and mobility with the intention of maximizing their HRQoL for discharge and thereafter. For this reason, longitudinal use of physical performance measures as an indicator of improvement in physical functioning (and thus HRQoL) is common. Although this is a logical approach, there have been mixed results from previous investigations into the association between common measures of physical function and HRQoL amongst other adult patient populations.1,2 There has been no previous investigation reporting the association between HRQoL and a variety of common physical performance measures in hospitalized older adults.

Impaired physical function associated with childhood obesity: How should we intervene?

- Background This study examined relationships between adiposity, physical functioning and physical activity. - Methods Obese (N=107) and healthy-weight (N=132) children aged 10-13 years underwent assessments of percent body fat (%BF, dual energy X-ray absorptiometry), knee extensor strength (KE, isokinetic dynamometry), cardiorespiratory fitness (CRF, peak oxygen uptake by cycle ergometry), physical health-related quality of life (HRQOL), worst pain intensity and walking capacity [six-minute walk (6MWT)]. Structural equation modelling was used to assess relationships between variables. - Results Moderate relationships were observed between %BF and 6MWT, KE strength corrected for mass and CRF relative to mass (r -.36 to -.69, P≤.007). Weak relationships were found between: %BF and physical HRQOL (r -.27, P=.008); CRF relative to mass and physical HRQOL (r -.24, P=.003); physical activity and 6MWT (r .17, P=.004). Squared multiple correlations showed that 29.6% variance in physical HRQOL was explained by %BF, pain and CRF relative to mass, while 28% variance in 6MWT was explained by %BF and physical activity. - Conclusions It appears that children with a higher body fat percentage have poorer KE strength, CRF and overall physical functioning. Reducing percent fat appears to be the best target to improve functioning. However, a combined approach to intervention, targeting reductions in body fat percentage, pain and improvements in physical activity and CRF may assist physical functioning.