From the Publisher:
Real-Time Systems is both a valuable reference for professionals and an advanced text for Computer Science and Computer Engineering students. 

Real world real-time applications based on research and practice

State-of-the-art algorithms and methods for validation

Methods for end-to-end scheduling and resource management

More than 100 illustrations to enhance understanding

Comprehensive treatment of the technology known as RMA (rate-monotonic analysis) methods

A supplemental Companion Website www.prenhall.com/liu

http://user.it.uu.se/~yi/courses/rts/dvp-rts-08/notes/Course-INFO.pdf

Real-Time Systems

BACKGROUND: Removing dental plaque may play a key role maintaining oral health. There is conflicting evidence for the relative merits of manual and powered toothbrushing in achieving this. This is an update of a Cochrane review first published in 2003, and previously updated in 2005. OBJECTIVES: To compare manual and powered toothbrushes in everyday use, by people of any age, in relation to the removal of plaque, the health of the gingivae, staining and calculus, dependability, adverse effects and cost. SEARCH METHODS: We searched the following electronic databases: the Cochrane Oral Health Group's Trials Register (to 23 January 2014), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2014, Issue 1), MEDLINE via OVID (1946 to 23 January 2014), EMBASE via OVID (1980 to 23 January 2014) and CINAHL via EBSCO (1980 to 23 January 2014). We searched the US National Institutes of Health Trials Register and the WHO Clinical Trials Registry Platform for ongoing trials. No restrictions were placed on the language or date of publication when searching the electronic databases. SELECTION CRITERIA: Randomised controlled trials of at least four weeks of unsupervised powered toothbrushing versus manual toothbrushing for oral health in children and adults. DATA COLLECTION AND ANALYSIS: We used standard methodological procedures expected by The Cochrane Collaboration. Random-effects models were used provided there were four or more studies included in the meta-analysis, otherwise fixed-effect models were used. Data were classed as short term (one to three months) and long term (greater than three months). MAIN RESULTS: Fifty-six trials met the inclusion criteria; 51 trials involving 4624 participants provided data for meta-analysis. Five trials were at low risk of bias, five at high and 46 at unclear risk of bias.There is moderate quality evidence that powered toothbrushes provide a statistically significant benefit compared with manual toothbrushes with regard to the reduction of plaque in both the short term (standardised mean difference (SMD) -0.50 (95% confidence interval (CI) -0.70 to -0.31); 40 trials, n = 2871) and long term (SMD -0.47 (95% CI -0.82 to -0.11; 14 trials, n = 978). These results correspond to an 11% reduction in plaque for the Quigley Hein index (Turesky) in the short term and 21% reduction long term. Both meta-analyses showed high levels of heterogeneity (I(2) = 83% and 86% respectively) that was not explained by the different powered toothbrush type subgroups.With regard to gingivitis, there is moderate quality evidence that powered toothbrushes again provide a statistically significant benefit when compared with manual toothbrushes both in the short term (SMD -0.43 (95% CI -0.60 to -0.25); 44 trials, n = 3345) and long term (SMD -0.21 (95% CI -0.31 to -0.12); 16 trials, n = 1645). This corresponds to a 6% and 11% reduction in gingivitis for the L�e and Silness index respectively. Both meta-analyses showed high levels of heterogeneity (I(2) = 82% and 51% respectively) that was not explained by the different powered toothbrush type subgroups.The number of trials for each type of powered toothbrush varied: side to side (10 trials), counter oscillation (five trials), rotation oscillation (27 trials), circular (two trials), ultrasonic (seven trials), ionic (four trials) and unknown (five trials). The greatest body of evidence was for rotation oscillation brushes which demonstrated a statistically significant reduction in plaque and gingivitis at both time points. AUTHORS' CONCLUSIONS: Powered toothbrushes reduce plaque and gingivitis more than manual toothbrushing in the short and long term. The clinical importance of these findings remains unclear. Observation of methodological guidelines and greater standardisation of design would benefit both future trials and meta-analyses.Cost, reliability and side effects were inconsistently reported. Any reported side effects were localised and only temporary.

Powered versus manual toothbrushing for oral health.

The Internet-of-Things (IoT) is the future of the Internet, where everything will be connected. Studies have revealed that fog/edge computing-based services will play a major role in extending the cloud by carrying out intermediary services at the edge of the network. Fog/edge computing-based IoT’s (FECIoT) distributed architecture enhances service provisioning along the Cloud-to-Things continuum, thereby making it suitable for mission-critical applications. Furthermore, the proximity of fog/edge devices to where the data is produced makes it stand-out in terms of resource allocation, service delivery, and privacy. From the business perspective, FECIoT will lead to a boom and spring up of small-to-medium-sized enterprises, thereby encouraging inclusion for all. To this end, we present a comprehensive survey on state-of-the-art IoT literature over the period 2008–2018 and propose the FECIoT framework which covers the enabling technologies, services, and open research issues. A tutorial approach is employed, progressing from basic to more advanced concepts within the IoT domain. Lastly, we show how FECIoT can be deployed in real-life cyber-physical systems, such as the intelligent transportation system, smart grid, smart health-care, smart homes, and smart environment.

Fog/Edge Computing-Based IoT (FECIoT): Architecture, Applications, and Research Issues

Background
Dental sealants were introduced in the 1960s to help prevent dental caries, mainly in the pits and fissures of occlusal tooth surfaces. Sealants act to prevent bacteria growth that can lead to dental decay. Evidence suggests that fissure sealants are effective in preventing caries in children and adolescents compared to no sealants. Effectiveness may, however, be related to caries incidence level of the population. This is an update of a review published in 2004, 2008 and 2013.

Objectives
To compare the effects of different types of fissure sealants in preventing caries in occlusal surfaces of permanent teeth in children and adolescents.

Search methods
Cochrane Oral Health’s Information Specialist searched: Cochrane Oral Health’s Trials Register (to 3 August 2016), the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library, 2016, Issue 7), MEDLINE Ovid (1946 to 3 August 2016), and Embase Ovid (1980 to 3 August 2016). We searched ClinicalTrials.gov and the World Health Organization International Clinical Trials Registry Platform for ongoing trials to 3 August 2016. No restrictions were placed on language or date of publication.

Selection criteria
Randomised controlled trials (RCTs) comparing sealants with no sealant or a different type of sealant material for preventing caries of occlusal surfaces of premolar or molar teeth in children and adolescents aged up to 20 years. Studies required at least 12 months follow-up. We excluded studies that compared compomers to resins/composites.

Data collection and analysis
Two review authors independently screened search results, extracted data and assessed risk of bias of included studies. We presented outcomes for caries or no caries on occlusal surfaces of permanent molar teeth as odds ratio (OR) or risk ratio (RR). We used mean difference (MD) for mean caries increment. All measures were presented with 95% confidence intervals (CI). We conducted meta-analyses using a random-effects model for comparisons where there were more than three trials; otherwise we used the fixed-effect model. We used GRADE methods to assess evidence quality.

Main results
We included 38 trials that involved a total of 7924 children; seven trials were new for this update (1693 participants). Fifteen trials evaluated the effects of resin-based sealant versus no sealant (3620 participants in 14 studies plus 575 tooth pairs in one study); three trials with evaluated glass ionomer sealant versus no sealant (905 participants); and 24 trials evaluated one type of sealant versus another (4146 participants). Children were aged from 5 to 16 years. Trials rarely reported background exposure to fluoride of trial participants or baseline caries prevalence.

Resin-based sealant versus no sealant: second-, third- and fourth-generation resin-based sealants prevented caries in first permanent molars in children aged 5 to 10 years (at 24 months follow-up: OR 0.12, 95% CI 0.08 to 0.19, 7 trials (5 published in the 1970s; 2 in the 2010s), 1548 children randomised, 1322 children evaluated; moderate-quality evidence). If we were to assume that 16% of the control tooth surfaces were decayed during 24 months of follow-up (160 carious teeth per 1000), then applying a resin-based sealant would reduce the proportion of carious surfaces to 5.2% (95% CI 3.13% to 7.37%). Similarly, assuming that 40% of control tooth surfaces were decayed (400 carious teeth per 1000), then applying a resin-based sealant would reduce the proportion of carious surfaces to 6.25% (95% CI 3.84% to 9.63%). If 70% of control tooth surfaces were decayed, there would be 19% decayed surfaces in the sealant group (95% CI 12.3% to 27.2%). This caries-preventive effect was maintained at longer follow-up but evidence quality and quantity was reduced (e.g. at 48 to 54 months of follow-up: OR 0.21, 95% CI 0.16 to 0.28, 4 trials, 482 children evaluated; RR 0.24, 95% CI 0.12 to 0.45, 203 children evaluated). Although studies were generally well conducted, we assessed blinding of outcome assessment for caries at high risk of bias for all trials (blinding of outcome assessment is not possible in sealant studies because outcome assessors can see and identify sealant).

Glass ionomer sealant versus no sealant: was evaluated by three studies. Results at 24 months were inconclusive (very low-quality evidence).

One sealant versus another sealant: the relative effectiveness of different types of sealants is unknown (very low-quality evidence). We included 24 trials that directly compared two different sealant materials. Comparisons varied in terms of types of sealant assessed, outcome measures chosen and duration of follow-up.

Adverse events: only four trials assessed adverse events. No adverse events were reported.

Authors' conclusions
Resin-based sealants applied on occlusal surfaces of permanent molars are effective for preventing caries in children and adolescents. Our review found moderate-quality evidence that resin-based sealants reduced caries by between 11% and 51% compared to no sealant, when measured at 24 months. Similar benefit was seen at timepoints up to 48 months; after longer follow-up, the quantity and quality of evidence was reduced. There was insufficient evidence to judge the effectiveness of glass ionomer sealant or the relative effectiveness of different types of sealants. Information on adverse effects was limited but none occurred where this was reported. Further research with long follow-up is needed.

Pit and fissure sealants for preventing dental decay in permanent teeth

The development process of complex systems needs to take in account differents domains and aspects. SysML (Systems Modeling Language) is a new modeling language that allows a system description with various integrated diagrams (as structure, behavior and requirements diagrams), but SysML lacks formality for the requirement verification. The aim of this paper is to propose an approach to verify complex systems using SysML as a language which describes the system structure and requirements. Petri nets and temporal logic LTL are used respectively to formalize the system behavior and requirements. The benefit of such formalization is to allow an automatic formal verification. In order to demonstrate this methodology, it will be used a factory automation system, modeled by SysML and Petri nets, and verified by the TINA toolbox.

/pdf/introducing-the-modeling-and-verification-process-in-sysml-2yb5zjszxt.pdf

Introducing the modeling and verification process in SysML

The aim of this study was to estimate the independent effects of biofilm accumulation and eruption stage on the occurrence of active caries lesions on occlusal surfaces of permanent molars. The sample consisted of 298 schoolchildren (6–15 years) who were examined by a calibrated examiner at a dental unit, using artificial light, a dental mirror and a WHO probe. The occurrence of visible biofilm on occlusal surfaces and the eruption stage of each permanent molar were recorded. After professional prophylaxis and air drying, the occlusal surfaces were classified as sound, caries-inactive or caries-active. To evaluate the association of eruption stage and biofilm accumulation with active caries lesions, a logistic regression model was used. Since data were clustered, odds ratios were obtained using generalized estimating equations with a logistic link function. 1,779 permanent molars were examined. All eruption stages were associated with active caries lesions. After adjustment for biofilm accumulation and type of molar, molars with occlusal surfaces partially exposed to the oral cavity were 63.6 times more susceptible to caries activity than molars with full occlusion (95% CI = 22.0–183.7). After adjustment for eruption stage and type of molar, teeth with a high degree of biofilm accumulation were 14.5 times more susceptible to caries activity than those without visible biofilm accumulation (95% CI = 6.5–32.4). No association between active caries and hardly detectable biofilm was found in this population. The present study found that the eruption stage of permanent molars is strongly associated with active caries lesions, adjusted for biofilm accumulation and type of molar.

Influence of eruption stage and biofilm accumulation on occlusal caries in permanent molars: a generalized estimating equations logistic approach.

The mobile agent technology is an important research area in the scope of code mobility. As part of an agent mission objective, it may exist the necessity of meeting an end-to-end deadline, although with some flexibility about the itinerary the agent should follow. The objective of this paper is to define an execution model for mobile agents that include timing constraints. We also show some simple heuristics that are able to guide these agents in the itinerary definition, considering the existence of an end-to-end deadline for the mission.

/pdf/dynamic-determination-of-the-itinerary-of-mobile-agents-with-4kpeixou1i.pdf

Dynamic determination of the itinerary of mobile agents with timing constraints

CORBA is an emerging middleware infrastructure with open standardization that is receiving a good acceptance since it allows easier programming of distributed objects. CORBA is being extended through the specification of interfaces and necessary abstractions to support applications with real time constraints. These new abstractions will enable a variety of programming models for real time applications. The paper presents an adaptive programming model for distributed real time applications using CORBA concepts. The model combines the time polymorphic invocation technique with the (m,k)-firm guarantee.

/pdf/an-adaptive-scheduling-approach-in-real-time-corba-3sloodg7ki.pdf

An adaptive scheduling approach in real-time CORBA

The Internet of Things is a new paradigm where smart embedded devices and systems are connected to the Internet. In this context, Wireless Sensor Networks (WSN) are becoming an important alternative for sensing and actuating critical applications like industrial automation, remote patient monitoring and domotics. The IEEE 802.15.4 protocol has been adopted as a standard for WSN and the 6LoWPAN protocol has been proposed to overcome the challenges of integrating WSN and Internet protocols. In this paper, the mechanisms of header compression and fragmentation of IPv6 datagrams proposed in the 6LoWPAN standard were evaluated through field experiments using a gateway prototype and IEEE 802.15.4 nodes.

R.S. de Oliveira

Papers

Introducing the modeling and verification process in SysML

Influence of eruption stage and biofilm accumulation on occlusal caries in permanent molars: a generalized estimating equations logistic approach.

Dynamic determination of the itinerary of mobile agents with timing constraints

An adaptive scheduling approach in real-time CORBA

Integration of Wireless Sensor Networks to the Internet of Things Using a 6LoWPAN Gateway