Dissertations / Theses: 'Safety functions'

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El-Basyouny, Karim. "New techniques for developing safety performance functions." Thesis, University of British Columbia, 2011. http://hdl.handle.net/2429/31254.

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While motorized travel provides many benefits, it can also do serious harm in the form of road-related collisions. The problem affects millions of human lives and costs billions of dollars in economic and social impacts every year. The problem could be addressed thorough several approaches with engineering initiatives being recognized as the most sustainable and cost effective. However, the success of the engineering approaches in reducing collision occurrences hinges upon the existence of reliable methods that provide accurate estimates of road safety. Currently, Safety Performance Functions (SPFs) are considered by many as the main tool in estimating the safety levels associated with different road entities. Therefore, the research in this thesis focuses on addressing key issues related to the development of SPFs for i) collision data analysis and ii) collision intervention analysis. Some of the key issues addressed include: 1) adding spatial effects to SPFs thereby recognizing the evident spatial nature of road collisions, 2) fitting hierarchical models to allow inference to be made on more than one level, 3) recognizing the multivariate nature of collisions as most data are available by collision type or severity and modeling the data as such, 4) identifying and accounting for outliers in the development of SPFs, 5) developing a novel evaluation methodology to estimate the effectiveness of safety countermeasures when subject to data limitations, and 6) compare different tools for investigating the safety change in treated sites due to the implementation of safety countermeasures. The applications of the various models have been demonstrated using several collision datasets and/or safety programs. The results provide strong evidence for (i) incorporating spatial effects in SPFs, (ii) clustering road segments or intersections into homogeneous groups (e.g., corridors, zones, districts, municipalities, etc.) and incorporating random cluster parameters in SPFs, (iii) developing robust multivariate models with multiple covariates for modeling collisions by severity and/or type concurrently, and (iv) the effectiveness of the proposed full Bayes safety assessment methods that account for several theoretical and practical issues concurrently. In addition to the improvement in goodness of fit, the proposed models have also improved inference and precision of expected collision frequency.

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Nguyen, Thien Duy. "Modeling of Safety Functions in Quantitative Risk Analysis." Thesis, Norges Teknisk-Naturvitenskaplige Universitet, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-21097.

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Quantitative risk analysis in the offshore industry is mandated by the Norwegian legislation. A literature survey is carried out, related to the current legislation from the Norwegian Petroleum Safety Authority (PSA) and supporting NORSOK standards. Process accidents on offshore installations, operating on the Norwegian continental shelf are emphasized. A risk picture is the synthesis of a risk assessment, describing the risk level. Requirements to the risk picture are discussed, and associated risk measures are presented. The risk measures represent the quantitative parts of a risk picture and the measures are evaluated against risk acceptance criteria. The evaluation can be performed with a mechanistic approach, or more flexibly by using the as low as reasonably practicable principle.Uncertainty is an important aspect that many quantitative risk analyses treat too briefly. Assumptions are always made in risk analyses, and uncertainty therefore becomes an important issue. To put it on the agenda, an introduction to the topic is given. The main purpose of a risk analysis is to support decision-making and the analysts should keep that in mind when performing the analysis. The field of quantitative risk analysis has received some criticisms, but some of it is unjust. To understand why, the scope of the quantitative risk analysis must be understood. Risk can be considered both from a strategic (long-term) and an operational (day-to-day) perspective. For quantitative risk analyses, a probabilistic view is used, dealing with probabilities and expected values. Strategic decision-making fits with this approach, but renders a day-to-day basis decision-making unsuitable. In addition, quantitative risk analysis copes with several types of hazards, with a long time span. The resources needed to handle all the hazards on an operational level of detail would be tremendous.Several methods can be used when performing a quantitative risk analysis. The approach used by Scandpower is explored in detail. The main method currently used is event tree analysis. This method has some challenges. A problem addressed is the treatment of dependencies, both within and between event trees. The answer is related to how RiskSpectrum, a fault and event tree software, calculates the end event frequencies. A second problem is the treatment of human reliability, and how it can be implemented in the event tree analyses.Large investments have been used on fire protection systems, to mitigate the consequences of process accidents. The thesis endeavors to study the importance of these safety systems. The emphasis is how the systems’ reliability is modeled and treated in a quantitative risk analysis. To investigate the effects of the safety systems on the risk measures, three quantitative risk analyses are explored in detail. This was executed by using sensitivity analyses. The sensitivity analyses are performed by altering the failure probabilities to the far ends. Astonishing results arisen. An attempt has been made to understand the mechanisms leading to the results. Possible explanations are discussed, and the three most important are outlined.An input to the quantitative risk analyses is reliability data of the safety systems, but there can be nonconformity between the data. Vendor data seems to be too optimistic related to the field performance. Possible explanations are discussed in the thesis.A best practice is presented, formed as an extended conclusion. Topics considered are:-Challenges when modeling the event trees-How to include vulnerability of the safety systems-Uncertainties with the effect of deluge-Human factors-Dependencies

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Ahmed, Mohamed. "Multi-Level Safety Performance Functions for High Speed Facilities." Doctoral diss., University of Central Florida, 2012. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/5091.

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High speed facilities are considered the backbone of any successful transportation system; Interstates, freeways, and expressways carry the majority of daily trips on the transportation network. Although these types of roads are relatively considered the safest among other types of roads, they still experience many crashes, many of which are severe, which not only affect human lives but also can have tremendous economical and social impacts. These facts signify the necessity of enhancing the safety of these high speed facilities to ensure better and efficient operation. Safety problems could be assessed through several approaches that can help in mitigating the crash risk on long and short term basis. Therefore, the main focus of the research in this dissertation is to provide a framework of risk assessment to promote safety and enhance mobility on freeways and expressways. Multi-level Safety Performance Functions (SPFs) were developed at the aggregate level using historical crash data and the corresponding exposure and risk factors to identify and rank sites with promise (hot-spots). Additionally, SPFs were developed at the disaggregate level utilizing real-time weather data collected from meteorological stations located at the freeway section as well as traffic flow parameters collected from different detection systems such as Automatic Vehicle Identification (AVI) and Remote Traffic Microwave Sensors (RTMS). These disaggregate SPFs can identify real-time risks due to turbulent traffic conditions and their interactions with other risk factors. In this study, two main datasets were obtained from two different regions. Those datasets comprise historical crash data, roadway geometrical characteristics, aggregate weather and traffic parameters as well as real-time weather and traffic data. At the aggregate level, Bayesian hierarchical models with spatial and random effects were compared to Poisson models to examine the safety effects of roadway geometrics on crash occurrence along freeway sections that feature mountainous terrain and adverse weather. At the disaggregate level; a main framework of a proactive safety management system using traffic data collected from AVI and RTMS, real-time weather and geometrical characteristics was provided. Different statistical techniques were implemented. These techniques ranged from classical frequentist classification approaches to explain the relationship between an event (crash) occurring at a given time and a set of risk factors in real time to other more advanced models. Bayesian statistics with updating approach to update beliefs about the behavior of the parameter with prior knowledge in order to achieve more reliable estimation was implemented. Also a relatively recent and promising Machine Learning technique (Stochastic Gradient Boosting) was utilized to calibrate several models utilizing different datasets collected from mixed detection systems as well as real-time meteorological stations. The results from this study suggest that both levels of analyses are important, the aggregate level helps in providing good understanding of different safety problems, and developing policies and countermeasures to reduce the number of crashes in total. At the disaggregate level, real-time safety functions help toward more proactive traffic management system that will not only enhance the performance of the high speed facilities and the whole traffic network but also provide safer mobility for people and goods. In general, the proposed multi-level analyses are useful in providing roadway authorities with detailed information on where countermeasures must be implemented and when resources should be devoted. The study also proves that traffic data collected from different detection systems could be a useful asset that should be utilized appropriately not only to alleviate traffic congestion but also to mitigate increased safety risks. The overall proposed framework can maximize the benefit of the existing archived data for freeway authorities as well as for road users.
ID: 031988164; System requirements: World Wide Web browser and PDF reader.; Mode of access: World Wide Web.; Thesis (Ph.D.)--University of Central Florida, 2012.; Includes bibliographical references.
Ph.D.
Doctorate
Civil, Environmental, and Construction Engineering
Engineering and Computer Science
Civil Engineering

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Lu, Jinyan. "Development of Safety Performance Functions for SafetyAnalyst Applications in Florida." FIU Digital Commons, 2013. http://digitalcommons.fiu.edu/etd/880.

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In 2010, the American Association of State Highway and Transportation Officials (AASHTO) released a safety analysis software system known as SafetyAnalyst. SafetyAnalyst implements the empirical Bayes (EB) method, which requires the use of Safety Performance Functions (SPFs). The system is equipped with a set of national default SPFs, and the software calibrates the default SPFs to represent the agency’s safety performance. However, it is recommended that agencies generate agency-specific SPFs whenever possible. Many investigators support the view that the agency-specific SPFs represent the agency data better than the national default SPFs calibrated to agency data. Furthermore, it is believed that the crash trends in Florida are different from the states whose data were used to develop the national default SPFs. In this dissertation, Florida-specific SPFs were developed using the 2008 Roadway Characteristics Inventory (RCI) data and crash and traffic data from 2007-2010 for both total and fatal and injury (FI) crashes. The data were randomly divided into two sets, one for calibration (70% of the data) and another for validation (30% of the data). The negative binomial (NB) model was used to develop the Florida-specific SPFs for each of the subtypes of roadway segments, intersections and ramps, using the calibration data. Statistical goodness-of-fit tests were performed on the calibrated models, which were then validated using the validation data set. The results were compared in order to assess the transferability of the Florida-specific SPF models. The default SafetyAnalyst SPFs were calibrated to Florida data by adjusting the national default SPFs with local calibration factors. The performance of the Florida-specific SPFs and SafetyAnalyst default SPFs calibrated to Florida data were then compared using a number of methods, including visual plots and statistical goodness-of-fit tests. The plots of SPFs against the observed crash data were used to compare the prediction performance of the two models. Three goodness-of-fit tests, represented by the mean absolute deviance (MAD), the mean square prediction error (MSPE), and Freeman-Tukey R2 (R2FT), were also used for comparison in order to identify the better-fitting model. The results showed that Florida-specific SPFs yielded better prediction performance than the national default SPFs calibrated to Florida data. The performance of Florida-specific SPFs was further compared with that of the full SPFs, which include both traffic and geometric variables, in two major applications of SPFs, i.e., crash prediction and identification of high crash locations. The results showed that both SPF models yielded very similar performance in both applications. These empirical results support the use of the flow-only SPF models adopted in SafetyAnalyst, which require much less effort to develop compared to full SPFs.

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Green, Eric R. "SEGMENTATION STRATEGIES FOR ROAD SAFETY ANALYSIS." UKnowledge, 2018. https://uknowledge.uky.edu/ce_etds/62.

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This dissertation addresses the relationship between roadway segment length and roadway attributes and their relationship to the efficacy of Safety Performance Function (SPF) models. This research focuses on three aspects of segmentation: segment length, roadway attributes, and combinations of the two. First, it is shown that choice of average roadway segment length can result in markedly different priority lists. This leads to an investigation of the effect of segment length on the development of SPFs and identifies average lengths that produce the best-fitting SPF. Secondly, roadway attributes are filtered to test the effect that homogeneity has on SPF development. Lastly, a combination of segment length and attributes are examined in the same context. In the process of conducting this research a tool was developed that provides objective goodness-of-fit measures as well as visual depictions of the model. This information can be used to avoid things like omitted variable bias by allowing the user to include other variables or filter the database. This dissertation also discusses and offers examples of ways to improve the models by employing alternate model forms. This research revealed that SPF development is sensitive to a variety of factors related to segment length and attributes. It is clear that strict base condition filters based on the most predominant roadway attributes provide the best models. The preferred functional form was shown to be dependent on the segmentation approach (fixed versus variable length). Overall, an important step in SPF development process is evaluation and comparison to determine the ideal length and attributes for the network being analyzed (about 2 miles or 3.2 km for Kentucky parkways). As such, a framework is provided to help safety professionals employ the findings from this research.

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Aziz, Syeda Rubaiyat. "Calibration of the Highway Safety Manual and development of new safety performance functions for rural multilane highways in Kansas." Diss., Kansas State University, 2016. http://hdl.handle.net/2097/32564.

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Doctor of Philosophy
Civil Engineering
Sunanda Dissanayake
Rural roads account for 90.3% of the 140,476 total centerline miles of roadways in Kansas. In recent years, rural fatal crashes have accounted for about 66% of all fatal crashes. The Highway Safety Manual (HSM) provides models and methodologies for analyzing the safety of various types of highways. Predictive methods in the HSM were developed based on national trends and data from few states throughout the United States. However, these methodologies are of limited use if they are not calibrated for individual jurisdictions or local conditions. The objective of this study was to analyze the HSM calibration procedures for rural multilane segments and intersections in Kansas. The HSM categorizes rural multilane segments as four-lane divided (4D) and four-lane undivided (4U) segments and rural multilane intersections as three-legged intersections with minor-road stop control (3ST), four-legged intersections with minor-road stop control (4ST), and four-leg signalized intersections (4SG). The number of predicted crashes at each segment was obtained according to the HSM calibration process. Results from calibration of rural segments indicated that the HSM overpredicts fatal and injury crashes by 50% and 65% and underpredicts total crashes by 48% and 64% on rural 4D and 4U segments, respectively. The HSM-given safety performance function (SPF) regression coefficients were then modified to capture variation in crash prediction. The adjusted models for 4D and 4U multilane segments indicated significant improvement in crash prediction for rural Kansas. Furthermore, Kansas-specific safety performance functions (SPF)s were developed following the HSM recommendations. In order to develop Kansas-specific SPF, Negative Binomial regression was applied to obtain the most suitable model. Several additional variables were considered and tested in the new SPFs, followed by model validation on various sets of locations. The Kansas-specific SPFs are capable of more accurately predicting total and fatal and injury crashes on multilane segments compared to the HSM and the modified HSM models. In addition to multilane segments, rural intersections on multilane highways were also calibrated according to the HSM methodology. Using crash modification factors for corresponding variables, SPFs were adjusted to obtain final predicted crash frequency at intersections. Obtained calibration factors indicated that the HSM is capable of predicting crashes at intersections at satisfactory level. Findings of this study can be used for improving safety of rural multilane highways.

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Stette, Sondre Bjørn. "Safety Functions in Different Operational Modes and IEC 61508 in the Hydropower Industry." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for produksjons- og kvalitetsteknikk, 2013. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-22369.

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Technical systems that comprise at least one electrical, electronic, or programmable electronic device and perform safety functions are called safety instrumented systems. Safety instrumented systems are used to reduce the risk related to hazardous events that may result in undesired consequences to humans, the environment, and assets, and the reliability of such systems is therefore important. The international standard IEC 61508 can be used to ensure safe and reliable safety instrumented systems, and it applies to all types of safety instrumented systems. Based on IEC 61508, the process industry and the machinery industry have developed their own versions called IEC 61511 and IEC 62061, respectively. IEC 61508 includes requirements for all activities necessary for achieving reliable safety instrumented systems throughout their whole lifecycle, and the standard introduces concepts and terminology that can be challenging to understand. Some basic concepts and terminology in IEC 61508 are clarified in this master thesis. A safety function, performed by a safety instrumented system, may be demanded from seldom to continuously. IEC 61508 distinguishes between safety functions that are demanded less frequent and more frequent than once per year, and these two modes of operation are called low-demand and high-demand, respectively. Furthermore, the standard requires that different reliability measures are used for demonstrating the reliability of the safety instrumented systems performing low-demand and high-demand safety functions. In two examples, the two reliability measures are used, and the calculated results show that there is an inconsistency with the classification of safety functions in IEC 61508. This inconsistency is, however, not experienced with the classification in IEC 61511, and the approach in IEC 61511 seems better. Other differences between low-demand and high-demand safety functions are not well explained in IEC 61508. Because IEC 61511 considers mainly low-demand safety functions and IEC 62061 considers only high-demand safety functions, specific requirements in these two standards are compared to reveal possible differences between low-demand and high-demand. It is concluded that there are essentially no differences between the compared requirements. Based on the event, loss of control, in an accident scenario, it is proposed a new approach for classifying safety functions. A definition of loss of control is suggested and it distinguishes between safety control functions and safety protection functions. These two functions are further related to two additional events in an accident scenario, and a model that illustrates the proposed classification in relation to the three events in an accident scenario is developed. The proposed classification is neither based on frequency of demands nor does it prescribe use of a specific reliability measure, and the classification is thus different from the classification in IEC 61508. The proposed classification is more similar to the classification in IEC 61511. Safety instrumented systems are used in the hydropower industry, but IEC 61508 is essentially not yet applied. The Machinery Directive requires machine manufacturers to meet the essential health and safety requirements, and some of these requirements can, for safety instrumented systems in machines, be met by complying with IEC 62061. Because IEC 62061 is based on IEC 61508, this is a relationship between IEC 61508 and the hydropower industry. From the perspective of a typical company operating hydropower plants in the Norwegian hydropower industry, some benefits and challenges related to implementation and use of IEC 61508 are discussed. IEC 61508 provides a rigorous, risk-based approach for achieving reliable safety instrumented systems and many of the concepts in the standard could be very useful in the hydropower industry. However, the standard is comprehensive and extensive resources and competence are prerequisites for successful implementation and use. It is concluded that IEC 61508 may not be what the hydropower industry needs, but a joint project for developing a unified approach for ensuring reliable safety instrumented systems may be a better option.

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Appel, Matt Andrew. "Security Control Mechanism for Safety Critical Functions Operating on Automotive Controller Area Network." The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1587645195243586.

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Frtunikj, Jelena [Verfasser]. "Safety Framework and Platform for Functions of Future Automotive E/E Systems / Jelena Frtunikj." München : Verlag Dr. Hut, 2016. http://d-nb.info/111333617X/34.

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Faden, Abdulrahman Khalid. "Development of Safety Performance Functions For Two-Lane Rural Highways in the State of Ohio." University of Dayton / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1591976280554876.

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Schönemann, Valerij [Verfasser], Hermann [Akademischer Betreuer] Winner, and Uwe [Akademischer Betreuer] Klingauf. "Safety Requirements and Distribution of Functions for Automated Valet Parking / Valerij Schönemann ; Hermann Winner, Uwe Klingauf." Darmstadt : Universitäts- und Landesbibliothek Darmstadt, 2019. http://d-nb.info/1200548086/34.

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Björklund, Fredrik, and Elin Karlström. "Enabling Testing of Lateral Active Safety Functions in a Multi-rate Hardware in the Loop Environment." Thesis, Linköpings universitet, Fordonssystem, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-139076.

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As the development of vehicles moves towards shorter development time, new ways of verifying the vehicle performance is needed in order to begin the verification process at an earlier stage. A great extent of this development regards active safety, which is a collection name for systems that help both avoid accidents and minimize the effects of a collision, e.g brake assist and steering control systems. Development of these active safety functions requires extensive testing and verification in order to guarantee the performance of the functions in different situations. One way of testing these functions is to include them in a Hardware in the Loop simulation, where the involved hardware from the real vehicle are included in the simulation loop. This master thesis investigates the possibility to test lateral active safety functions in a hardware in the loop simulation environment consisting of multiple subsystems working on different frequencies. The subsystems are all dependent of the output from other subsystems, forming an algebraic loop between them. Simulation using multiple hardware and subsystems working on different frequencies introduces latency in the simulation. The effect of the latency is investigated and proposed solutions are presented. In order to enable testing of lateral active safety functions, a steering model which enables the servo motor to steer the vehicle is integrated in the simulation environment and validated.

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Brimley, Bradford Keith. "Calibration of the Highway Safety Manual Safety Performance Function and Development of Jurisdiction-Specific Models for Rural Two-Lane Two-Way Roads in Utah." BYU ScholarsArchive, 2011. https://scholarsarchive.byu.edu/etd/2611.

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This thesis documents the results of the calibration of the Highway Safety Manual (HSM) safety performance function (SPF) for rural two-lane two-way roadway segments in Utah and the development of new SPFs using negative binomial and hierarchical Bayesian modeling techniques. SPFs estimate the safety of a roadway entity, such as a segment or intersection, in terms of number of crashes. The new SPFs were developed for comparison to the calibrated HSM SPF. This research was performed for the Utah Department of Transportation (UDOT).The study area was the state of Utah. Crash data from 2005-2007 on 157 selected study segments provided a 3-year observed crash frequency to obtain a calibration factor for the HSM SPF and develop new SPFs. The calibration factor for the HSM SPF for rural two-lane two-way roads in Utah is 1.16. This indicates that the HSM underpredicts the number of crashes on rural two-lane two-way roads in Utah by sixteen percent. The new SPFs were developed from the same data that were collected for the HSM calibration, with the addition of new data variables that were hypothesized to have a significant effect on crash frequencies. Negative binomial regression was used to develop four new SPFs, and one additional SPF was developed using hierarchical (or full) Bayesian techniques. The empirical Bayes (EB) method can be applied with each negative binomial SPF because the models include an overdispersion parameter used with the EB method. The hierarchical Bayesian technique is a newer, more mathematically-intense method that accounts for high levels of uncertainty often present in crash modeling. Because the hierarchical Bayesian SPF produces a density function of a predicted crash frequency, a comparison of this density function with an observed crash frequency can help identify segments with significant safety concerns. Each SPF has its own strengths and weaknesses, which include its data requirements and predicting capability. This thesis recommends that UDOT use Equation 5-11 (a new negative binomial SPF) for predicting crashes, because it predicts crashes with reasonable accuracy while requiring much less data than other models. The hierarchical Bayesian process should be used for evaluating observed crash frequencies to identify segments that may benefit from roadway safety improvements.

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Demireva, Petya D. "The Relationship of Executive Functions to Performance in a Driving Simulator in Healthy Older Adults." Ohio University / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1386333334.

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Devarasetty, Prem Chand. "SAFETY IMPROVEMENTS ON MULTILANE ARTERIALS A BEFORE AND AFTER EVALUATION USING THE EMPIRICAL BAYES METHOD." Master's thesis, Orlando, Fla. : University of Central Florida, 2009. http://purl.fcla.edu/fcla/etd/CFE0002723.

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Knecht, Casey Scott. "Crash Prediction Modeling for Curved Segments of Rural Two-Lane Two-Way Highways in Utah." BYU ScholarsArchive, 2014. https://scholarsarchive.byu.edu/etd/4352.

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This thesis contains the results of the development of crash prediction models for curved segments of rural two-lane two-way highways in the state of Utah. The modeling effort included the calibration of the predictive model found in the Highway Safety Manual (HSM) as well as the development of Utah-specific models developed using negative binomial regression. The data for these models came from randomly sampled curved segments in Utah, with crash data coming from years 2008-2012. The total number of randomly sampled curved segments was 1,495. The HSM predictive model for rural two-lane two-way highways consists of a safety performance function (SPF), crash modification factors (CMFs), and a jurisdiction-specific calibration factor. For this research, two sample periods were used: a three-year period from 2010 to 2012 and a five-year period from 2008 to 2012. The calibration factor for the HSM predictive model was determined to be 1.50 for the three-year period and 1.60 for the five-year period. These factors are to be used in conjunction with the HSM SPF and all applicable CMFs. A negative binomial model was used to develop Utah-specific crash prediction models based on both the three-year and five-year sample periods. A backward stepwise regression technique was used to isolate the variables that would significantly affect highway safety. The independent variables used for negative binomial regression included the same set of variables used in the HSM predictive model along with other variables such as speed limit and truck traffic that were considered to have a significant effect on potential crash occurrence. The significant variables at the 95 percent confidence level were found to be average annual daily traffic, segment length, total truck percentage, and curve radius. The main benefit of the Utah-specific crash prediction models is that they provide a reasonable level of accuracy for crash prediction yet only require four variables, thus requiring much less effort in data collection compared to using the HSM predictive model.

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Kimmitt, Jonathan R. R. "A type-safe apparatus executing higher order functions in conjunction with hardware error tolerance." Thesis, Anglia Ruskin University, 2015. http://arro.anglia.ac.uk/581958/.

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The increasing commoditization of computers in modern society has exceeded the pace of associated developments in reliability. Although theoretical computer science has advanced greatly in the last thirty years, many of the best techniques have yet to find their way into embedded computers, and their failure can have a great potential for disrupting society. This dissertation presents some approaches to improve computer reliability using software and hardware techniques, and makes the following claims for novelty: innovative development of a toolchain and libraries to support extraction from dependent type checking in a theorem prover; conceptual design and deployment in reconfigurable hardware; an extension of static type-safety to hardware description language and FPGA level; elimination of legacy C code from the target and toolchain; a novel hardware error detection scheme is described and compared with conventional triple modular redundancy. The elimination of any user control of memory management promotes robustness against buffer overruns, and consequently prevents vulnerability to common Trojan techniques. The methodology identifies type punning as a key weakness of commonly encountered embedded languages such as C, in particular the extreme difficulty of determining if an array access is in bounds, or if dynamic memory has been properly allocated and released. A method of eliminating dependence on type-unsafe libraries is presented, in conjunction with code that has optionally been proved correct according to user-defined criteria. An appropriately defined subset of OCaml is chosen with support for the Coq theorem prover in mind, and then evaluated with a custom backend that supports behavioural Verilog, as well as a fixed execution unit and associated control store. Results are presented for this alternative platform for reliable embedded systems development that may be used in future industrial flows. To provide assurance of correct operation, the proven software needs to be executed in an environment where errors are checked and corrected in conjunction with appropriate exception processing in the event of an uncorrectable error. Therefore, the present author’s previously published error detection scheme based on dual-rail logic and self-checking checkers is further developed and compared with traditional N-modular redundancy.

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Löbl, David [Verfasser], Florian [Akademischer Betreuer] Holzapfel, Manfred [Gutachter] Hajek, and Florian [Gutachter] Holzapfel. "A Total Capability Approach for the Development of Safety-Critical Functions / David Löbl ; Gutachter: Manfred Hajek, Florian Holzapfel ; Betreuer: Florian Holzapfel." München : Universitätsbibliothek der TU München, 2018. http://d-nb.info/1163728675/34.

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McCarthy, Ross James. "Reducing Highway Crashes with Network-Level Continuous Friction Measurements." Diss., Virginia Tech, 2019. http://hdl.handle.net/10919/103702.

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When a vehicle changes speed or direction, the interaction between the contacting surfaces of the tire and the pavement form frictional forces. The pavement's contribution to tire-pavement friction is referred to as skid resistance and is provided by pavement microtexture and macrotexture. The amount of skid resistance depreciates over time due to the polishing action of traffic, and for this reason, the skid resistance should be monitored with friction testing equipment. The equipment use one of four test methods to measure network-level friction: ASTM E 274 locked-wheel, ASTM E 2340 fixed-slip technique, ASTM E 1859 variable-slip technique, and sideways-force coefficient (SFC) technique. The fixed-slip, variable-slip, and SFC techniques are used in continuous friction measurement equipment (CFME). In the United States, skid resistance is traditionally measured with a locked-wheel skid trailer (LWST) equipped with either a ASTM E 501 ribbed or a ASTM E 524 smooth 'no tread' tire. Since the LWST fully-locks the test wheel to measure friction, it is only capable of spot testing tangent sections of roadway. By contrast, the remaining three test methods never lock their test wheels and, therefore, they can collect friction measurements continuously on all types of roadway, including curves and t-intersections. For this reason, highway agencies in the U.S. are interested in transitioning from using a LWST to using one of three continuous methods. This dissertation explores the use of continuous friction measurements, collected with a Sideways-force Coefficient Routine Investigation Machine (SCRIM), in a systemic highway safety management approach to reduce crashes that result in fatalities, injuries, and property damage only. The dissertation presents four manuscripts. In the first manuscript, orthogonal regression is used to develop models for converting between friction measurements with a SCRIM and LWST with both a ribbed and smooth tire. The results indicated that the LWST smooth tire measured friction with greater sensitivity to changes in macrotexture than the SCRIM and LWST ribbed tire. The SCRIM also had greater correlation to the LWST ribbed tire than the LWST smooth tire. The second investigation establishes the relationship between friction measured with a SCRIM and the risk of crashes on dry and wet pavement surfaces. The results of this showed that increasing friction decreases both dry and wet pavement crashes; however, friction was found to have greater impact in wet conditions. Due to the negative relationship between friction and crashes, eventually there will be a point where further losses in friction can result in a rapid increase in crash risk. This point can be identified with a friction threshold known as an investigatory level. When measured friction is at or below the investigatory level, an in- and out-of-field investigation is required to determine whether a countermeasure is necessary to improve safety. The third manuscript proposes a statistical regression approach for determining investigatory levels. Since this approach relies on statistical regression, the results are objective and should be the same for any analyst reviewing the same data. The investigatory levels can be used in a systemic approach that identifies locations where crashes can be reduced based on a benefit-cost analysis of surface treatments. Last, the forth manuscript demonstrates a benefit-cost analysis that selects surface treatments based on crash reductions predicted with continuous friction measurements.
Doctor of Philosophy
When a vehicle changes speed or direction, the tires slide over the pavement surface, creating friction that produces the traction that is necessary for the vehicle to change speed or direction. Friction can diminish when water, dust, and other contaminants are present, or over time due to traffic. Over time, the loss in friction causes the risk of a crash to increase. However, this relationship is non-linear, and therefore, eventually there will be a point where further losses in friction can cause a rapid increase in crash risk. For this reason, the pavement friction is monitored with equipment that slides a rubber tire with known properties over a pavement surface. Since friction is lowest when the pavement is wet, the equipment applies a film of water to the surface directly in front of the sliding tire. There are different types of equipment used to measure friction. The physical designs of the equipment and their method of testing may be different. For example, some devices measure friction by sliding a wheel that is angled away from the path of the vehicle, while others slide a wheel that is aligned with the vehicle but reduced in speed compared to the vehicle. The factors that make the equipment different can affect the quantity of friction that is measured, as well as the timing between each consecutive measurement. The advantages that some equipment offers can entice highway agencies to transition from a pre-existing system to a more advantageous system. Before transitioning, the measurements from the two types of equipment should be compared directly to determine their correlation. Statistical regression can also be used to develop models for converting the measurements from the new equipment to the units of the current, which can help engineers interpret the measurements, and to integrate them into an existing database. The presence of water on a pavement surface can result in a temporary loss of friction that can increase the risk of a crash beyond the normal, dry pavement state. This does not guarantee that dry pavements have sufficient friction as is suggested in most literature. In this dissertation, the relationship between friction and the risk of a crash on dry and wet pavements are evaluated together. The results show that increasing friction can decrease the crash risk on both dry and wet pavement surfaces. The amount of friction that is needed to maintain low crash risk is not the same for every section of road. Locations such as approaches to curves or intersections can increase the risk of a crash, and for that reason, some sections of roadway require more friction than others. Minimum levels of friction called investigatory levels can be established to trigger an in- and out-of-field investigation to determine whether improving friction can improve safety when the measured friction is at or below a specific value. This dissertation proposes a methodology for determining the investigatory levels of friction for different sections of roadway using a statistical regression approach. The investigatory levels are then used to identify locations where pavement surface treatments can reduce crashes based on a benefit-cost analysis. Last, the ability of a surface treatment to reduce crashes is evaluated using another statistical regression approach that predicts changes in crash risk using friction measurements. Since there are several treatment options, a treatment is selected based on estimated cost and benefit.

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Hållström, Mattias. "EDL(s) Electronic Driving License(s) : To increase traffic safety and improve other functions vital to society by implementing and deploying an electronic driving license (EDL) framework." Thesis, Umeå universitet, Institutionen för datavetenskap, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-102495.

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Researcher Fred Goldberg closed a report by expressing, "It is now up to the politicians to create a safer traffic environment by utilizing new technology for the benefit of society" (Goldberg, 1995). And as he stated prior to that quote, a technique is available to prevent unlawful driving, to effectively reduce drunken driving and, among other things, to reduce theft of cars. This report presents the available technology and design that make it possible to incorporate an electronic driving license (EDL) framework into everyday life. This report will focus on how such technology could be used to prevent drivers from driving without valid driving licenses and to improve traffic safety in numerous other ways. The report presents the existing laws and regulations that govern the area of usage and describes how such legal aspects affect the design and deployment of an EDL framework. The presented legislation is extracted primarily from the European Union in general, and as a national example, Swedish legislation is often used. Moreover, the report will present technology that could be used to implement an EDL framework using examples of implementations and design, including license verification and an EDL. The implementation and deployment of an EDL framework could result in privacy concerns, and such aspects are discussed in a chapter where it is stated that security and privacy issues must be considered, as the potential for misuse is great. The level of privacy must be analysed in relation to the lifesaving potential of such a framework.

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Montgomery, Daniel J. "Conceptual data model for administrative functions of a typical naval ship, to include : Drug and Alcohol Program Advisor, Watch Quarter and Station Bill, Safety, Medical, and Security." Thesis, Monterey, California. Naval Postgraduate School, 1991. http://hdl.handle.net/10945/26431.

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Peng, Yong. "In-depth accident investigation of pedestrian impact dynamics and development of head injury risk functions." Thesis, Strasbourg, 2012. http://www.theses.fr/2012STRAD024.

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Les piétons comptent parmi les usagers de la route les plus vulnérables dans la mesure où ils ne bénéficient d'aucune protection en cas d'impact avec un véhicule automobile. Plus de 1,17 millions de personnes sont tués sur la route de part le monde dont environ 65% ce piétons. Les blessures de la tête, souvent fatales, concernent environ 30 % des blessures enregistrées. Ces blessures conduisent à des incapacités de longue durée avec un coût sociétal et économique immense. Il est par conséquent essentiel de comprendre aussi bien les mécanismes d'accidents que les mécanismes de blessure de la tête afin d'intervenir sur la conception de la face avant des véhicules automobile. Dans ce contexte l'objet de la présente thèse est d'analyser la répons dynamique du piton en cas d'accident et ce contribuer au développement de critères de blessure de la tête. Dans le but d'étudier l'influence de la position du piéton, de la géométrie de la face avant du véhicule et de sa vitesse initiale sur la cinématique du piéton et les conditions d'impact de la tête, une simulation multi-corps a été mise en place. Les résultats de ces simulations donnent la vitesse et l'angle d'impact de la tête et la position de l'impact sur le véhicule. Cette analyse paramètrique a été conduite sur cinq types de véhicules et pour un modèle humain adulte et enfant de 6 ans et a permis de consolider les connaissances sur la conditions d'impact de la tête en comparaison avec les tests normatifs en vigueur.[...]
Pedestrians are regarded as an extremely vulnerable and high-risk group of road users since they are unprotected in vehicle impacts. More than 1.17 million people throughout the world are killed in road traffic accidents each year. Where, about 65% of deaths involve pedestrians. The head injuries in vehicle-pedestrian collisions accounted for about 30% of all reported injuries on different body regions, which often resulted in a fatal consequence. Such injuries can result in disabilities and long-term sequence, which lead to significant social costs. It is therefore important to study the characteristics of pedestrian accidents and understand the head injury mechanism of the pedestrian so as to improve vehicle design for pedestrian protection. The aim of this study is to investigate pedestrian dynamic response and develop head injury risk functions.In order to investigate the effect of pedestrian gait, vehicle front geometry and impact velocity on the dynamic responses of the head, the multi-body dynamic (MBD) models were used to simulate the head responses in vehicle to pedestrian collisions with different vehicle types in terms of head impact point measured with Wrap Around Distance (WAD), head relative velocity and impact angle. A simulation matrix is established using five vehicle types, and two mathematical models of the pedestrians represented a 50th male adult and a 6 year old child as well as seven pedestrian gaits based on typical postures in pedestrian accidents. In order to simulate a large range of impact conditions, four vehicle velocities (30 km/h, 40 km/h, 50 km/h and 60 km/h) are considered for each pedestrian position and vehicle type.A total of 43 passenger car versus pedestrian accidents were selected from In-depth Investigation of Vehicle Accidents in Changsha, China (IVAC) and German In-Depth Accident Study (GIDAS) database for simulation study. According to real-world accident investigation, accident reconstructions were conducted using multi-body system (MBS) pedestrian and car models under MADYMO simulation environment to calculate head impact conditions, in terms of head impact velocity, head position and head orientation. In order to study kinematics of adult pedestrian, relationship curves: head impact time, throw distance, head impact velocity and vehicle impact velocity, were computed and logistic regression models: head impact velocity, resultant angular velocity, HIC value, head contact force and head injuries, were developed based on the results from accident reconstructions.The automobile windshield, with which pedestrians come into frequent contact, has been identified as one of the main contact sources for pedestrian head injuries. In order to investigate the mechanical behavior of windshield laminated glass in the caseof pedestrian head impact, windshield FE models were set up using different combination for the modeling of glass and PVB, with various connection types and two mesh sizes (5 mm and 10 mm). Each windshield model was impacted with a standard adult headform impactor in an LS-DYNA simulation environment, and the results were compared with the experimental data reported in the literatures.In order to assess head injury risks of adult pedestrians, accident reconstructions were carried out by using Hybrid III head model based on the real-world pedestrian accidents. The impact conditions were obtained from the MBS simulation, including head impact velocity, head position and head orientation. They were used to set the initial conditions in a simulation of a Hybrid III FE head model striking a windshield FE model. Logistic regression models, Skull Fracture Correlate (SFC), head linear acceleration, Head Impact Power (HIP), HIC value, resultant angular acceleration and head injuries, were developed to study brain injury risk.{...]

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Plocek, Jaroslav. "Řízení jednoúčelového obráběcího stroje." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2015. http://www.nusl.cz/ntk/nusl-232092.

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The master thesis treats the design of control system of special purpose machine tool. The first part analyzes and compares two possible variants of control system which use either a CNC control system Sinumerik or motion control system Simotion. Only the variant with the Simotion control system is subsequently examined in detail: its hardware configuration, the selection of components and partly also the software solution. The thesis further deals with the safety of the realized control system and of the whole machine. There are described general safety requirements of machinery based on harmonized European standards and their specific application in the design of safety functions and the safety circuits of solved machine tool.

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Vaišvilienė, Jolanta. "Greitosios medicinos pagalbos pasirengimo veikti ekstremalių situacijų atvejais tyrimas." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2014. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2014~D_20140618_233423-53499.

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Darbo tikslas. Įvertinti greitosios medicinos pagalbos pasirengimą ekstremalių situacijų atvejais. Darbo uždaviniai: 1. Įvertinti VšĮ Kėdainių PSPC GMP skyriaus pasirengimą veikti ekstremalių situacijų atvejais kitų panašias paslaugas teikiančių įstaigų kontekste. 2. Įvertinti VšĮ Kėdainių PSPC GMP skyriaus pasirengimo veiklai ES atveju pokyčius 2013-2014m., įdiegus pasirengimo veiklai ir planavimo ES metodiką. 3. Ištirti įstaigos operatyvumo rodiklių pokyčius įdiegus naują GMP kvietimo valdymo sistemą. 4. Įstaigos patirties veikti ekstremaliose situacijose analizė. Darbo metodika: GMP įstaigų vadovų struktūrizuota apklausa. Tiesioginis Kėdainių GMP pasirengimo veikti ekstremaliose situacijose vertinimas. Įstaigos operatyvumo rodiklių pokyčių analizė. Kėdainių GMP skyriaus darbuotojų, dalyvavusių teikiant pagalbą masinių nelaimių atvejais struktūrizuotas interviu. Rezultatai: Tyrime dalyvavusių įstaigų bendrasis saugumo indeksas skirtingų dydžių GMP tarpe pasiskirstė tolygiai. Daugumos vadovų nuomone, jų įstaigų bendrasis saugumo indeksas yra pakankamas (72 proc. – 91proc.). VšĮ Kėdainių PSPC, GMP skyriuje, vertinant 2013 – 2014m. pasirengimo veiklai ES atveju, įvyko teigiami pokyčiai. Bendras saugomo indeksas nuo 0,78 išaugo iki 0,93. Įdiegus GMP iškvietimų ir pajėgų valdymo sistemą, operatyvumo rodikliai tapo tikslesni. Lyginant 2012m. ir 2013m. iškvietimų, neatitinkančių minimalių laiko kriterijų, skaičius mieste padidėjo nuo 3,9 iki 5,3 proc. (p=0,002). 2013m. pirmajame... [toliau žr. visą tekstą]
Aim of the study: to assess disaster preparedness of health care institutions providing emergency medical services (EMS). Objectives: 1. To assess disaster preparedness of Kėdainiai EMS in context of other similar institutions. 2. To evaluate changes of disaster preparedness of Kedainiai EMS after implementation of guidelines for disaster preparedness and planning in 2013-2014. 3. To evaluate changes of operative performance indicators after implementation of the new dispatch and ambulances’ management system in Kedainiai EMS. 4. To analyze experience of Kėdainiai EMS in recent disasters. Methods:Structured interview of EMS institutions managers. Direct measurement of Kėdainiai EMS preparedness to respond in emergency situations. Analysis of changes of operative performance indicators. Structured interview of Kėdainiai EMS staff who had experience in recent disasters. Results: In opinion of the majority of managers, their institutions safety index is sufficient (72% - 91%). There were positive changes in disaster preparedness in Kedainiai EMS in 2013-2014: Overall safety index increased from 0,78 to 0,93. Operative performance indicators became more accurate after installation of dispatch and ambulance management system. Proportion of calls, when ambulance response time that does not meet minimum arrival time requirements, increased from 3.9% to 5.3% in the year 2012 – 2013 (p=0,002). In the first quarter of 2013 right after installation of the system, this performance... [to full text]

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Shastry, Akshay Kumar. "Functional Safety Assessment in Autonomous Vehicles." Thesis, Virginia Tech, 2018. http://hdl.handle.net/10919/83483.

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Autonomous vehicles (AVs) are a class of safety-critical systems that are capable of decision-making and operate with little or no human intervention. For such complex systems designed to function in diverse operational domains such as rain, snow, freeway, urban roads, etc., system safety is paramount. Management of the system's safety throughout its life-cycle, from the conceptualization stage to the end of the lifecycle, is of primary importance. We describe a revision of functional safety standard ISO 26262 to support autonomous vehicles and the underlying electronic/electrical control architecture. There is a need to modify the Automotive Safety Integrity Levels (ASILs) defined in the ISO 26262 as "Controllability", a factor in determining an ASIL, is no longer applicable; the driver is no longer in a position to control the vehicle. The vehicle has taken over the responsibility of evaluating the environment and determines its next course of action to complete its current mission. These decisions have a tremendous impact on the overall safety of the system during a hazardous event and can be the difference between a successful journey and a traffic incident. To better enable the designers of such systems, we introduce a new method to assess the functional safety and derive safety goals, which are the top level safety requirement. We present a new metric-Risk Mitigation Factor to assess the decision making capability of the vehicle and to replace controllability in the ASIL definition. The case study presented highlights the advantages of using the introduced metric in defining safety goals for the autonomous vehicle.
Master of Science

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26

Sandom, Carl William. "Situational awareness and interactive system safety analysis." Thesis, Brunel University, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.289899.

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Beatriz, Ricardo Filipe Martins. "Safety function analysis in an industrial production process." Master's thesis, Faculdade de Ciências e Tecnologia, 2012. http://hdl.handle.net/10362/8075.

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Dissertação para obtenção do Grau de Mestre em Engenharia e Gestão Industrial
Aim: The purpose of this work was to identify and assess safety features on a production line of paper manufacturer called Renova. The assessment includes technical as well as organisational factors. The study was carried out through the evaluation of safety functions (SF), either present or absent in the system analyzed. Methods: The methodology applied was the SFA (Safety Function Analysis), which was developed by Harms-Ringdahl in 2001 and was updated further, in 2011 (draft version). The analytical framework was applied in two processes (raw material loading and transversal cut of log) of a production line (Line H4) of Renova. Results: In the first process analyzed (raw material loading), 47 safety functions (SF) were identified and evaluated, whereas 36 SF were assessed in the second case (transversal cut of log). The evaluation has shown that most of the SF considered are in good condition and being well monitored, therefore they do not need any improvements. In contrast, this work has also identified a number of safety functions that need essential improvements. Conclusions: As a consequence of this SFA analysis, the author proposes a number of specific recommendations to improve safety and the system’s performance in general. Since Renova is a manufacturer of paper products, fire safety is of paramount importance and one of the most relevant recommendations is perhaps the implementation of thermo graphic tests to identify possible hot spots that may originate a fire.

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Fischer, Eric, André Sitte, Jürgen Weber, Erhard Bergmann, and la Motte Markus de. "Performance of an electro-hydraulic active steering system." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-199643.

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Hydrostatic steering systems are used in construction and agricultural machines alike. Because of their high power density, hydraulic drives are qualified for the use in vehicles with high steering loads. Conventional hydrostatic steering systems are limited in terms of steering comfort and driver assistance. For realisation of appropriate steering functions, electro-hydraulic solutions are necessary. This paper provides an overview on existing implementations and introduces a novel steering system. The presented active steering system with independent meter-in and meter-out valves fills the gap between existing active steering systems and steer-by-wire solutions. An appropriate control and safety concept provides advanced steering functions for on-road usage without the fully redundant structure of steer-by-wire systems.

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Šindelek, Milan. "CIP Safety." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2016. http://www.nusl.cz/ntk/nusl-240916.

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This master’s thesis deals with the security machinery using available technologies. It contains a description to assess and reduce the risk of machine design of security measures and their application. In each section are provides descriptions of the standards, using the CIP Safety communication technology, design and implementation security measures of machine at two demonstration learning tasks.

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Wu, Guofan. "Safety-critical Geometric Control Design with Application to Aerial Transportation." Research Showcase @ CMU, 2017. http://repository.cmu.edu/dissertations/1108.

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Safety constraints are ubiquitous in many robotic applications. For instance, aerial robots such as quadrotors or hexcoptors need to realize fast collision-free flight, and bipedal robots have to choose their discrete footholds properly to gain the desired friction and pressure contact forces. In this thesis, we address the safety critical control problem for fully-actuated and under-actuated mechanical systems. Since many mechanical systems evolve on nonlinear manifolds, we extend the concept of Control Barrier Function to a new concept called geometric Control Barrier Function which is specifically designed to handle safety constraints on manifolds. This type of Control Barrier Function stems from geometric control techniques and has a coordinate free and compact representation. In a similar fashion, we also extend the concept of Control Lyapunov Function to the concept of geometric Control Lyapunov Function to realize tracking on the manifolds. Based on these new geometric versions of CLF and CBF, we propose a general control design method for fully-actuated systems with both state and input constraints. In this CBF-CLF-QP control design, the control input is computed based on a state-dependent Quadratic Programming (QP) where the safety constraints are strictly enforced using geometric CBF but the tracking constraint is imposed through a type of relaxation. Through this type of relaxation, the controller could still keep the system state safe even in the cases when the reference is unsafe during some time period. For a single quadrotor, we propose the concept of augmented Control Barrier Function specifically to let it avoid external obstacles. Using this augmented CBF, we could still utilize the idea of CBF-CLF-QP controller in a sequential QP control design framework to let this quadrotor remain safe during the flight. In meantime, we also apply the geometric control techniques to the aerial transportation problem where a payload is carried by multiple quadrotors through cable suspension. This type of transportation method allows multiple quadrotors to share the payload weight, but introduces internal safety constraints at the same time. By employing both linear and nonlinear techniques, we are able to carry the payload pose to follow a pre-defined reference trajectory.

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Zhang, Jiyu. "Model-Based Fault Diagnosis For Automotive Functional Safety." The Ohio State University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=osu1480665190516692.

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Keniausytė, Inga. "Darbuotojų saugos ir sveikatos tarnybų veiklos vertinimas Lietuvos energetikos sektoriaus įmonėse." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2014. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2010~D_20140625_190301-16339.

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Darbo jėgą sudaro apie 45 % pasaulio gyventojų. Profesinės traumos, su darbu susijusios ligos turi didelę reikšmę darbuotojų sveikatai. Ligos, kurios nesusijusios su darbu, gali taip pat turėti įtakos darbo našumui. Darbuotojų saugos ir sveikatos tarnybos plačiai pripažįstamos kaip esminis sveikesnės ir saugesnės darbo aplinkos kūrimo elementas. Darbo tikslas – įvertinti Darbuotojų saugos ir sveikatos tarnybų veiklą Lietuvos energetikos sektoriaus įmonėse. Darbo tikslui pasiekti buvo iškelti šie uždaviniai: įvertinti Lietuvos Darbuotojų saugos ir sveikatos tarnybų funkcijų atitikimą TDO 161 (ILO 161) konvencijai; nustatyti vykdomas Lietuvos energetikos sektoriaus įmonių Darbuotojų saugos ir sveikatos tarnybų funkcijas; įvertinti Lietuvos energetikos sektoriaus įmonių Darbuotojų saugos ir sveikatos žmogiškųjų resursų atitikimą Lietuvos Respublikos teisės aktams. Lietuvos DSS tarnybų funkcijų atitikimas TDO 161 konvencijai buvo vertinamas pagal 11 funkcijų, reglamentuotų konvencijoje. DSS tarnybų funkcijos ir žmogiškieji resursai nustatyti atlikus anketinė apklausą, kuri atlikta 2009 m. lapkričio – gruodžio mėnesiais. Naudota anketa sudaryta remiantis Pasaulinės sveikatos organizacijos rekomendacijomis: „Regioninės rekomendacijos: Sveikos darbo vietos plėtra“ ir „Pagrindinės profesinės sveikatos tarnybos“. Tyrimo metu atlikus anketinę apklausą ištirta 14 (53,8 proc.) energetikos sektoriaus DSS tarnybų. Lietuvos DSS tarnybų funkcijų atitikimas parodė, kad šių tarnybų veiklos... [toliau žr. visą tekstą]
Labour force is constituted of some 45 per cent of the world population. Occupational injuries, as well as work related diseases have a lot of influence on health of the labour force. Diseases, which are not related to work, may also have an impact on efficiency of work. Occupational health and safety (OHS) services are widely recognized as the essential element of healthier and more secure labour environment. The aim of the work is to evaluate activities of OHS services in energy sector companies in Lithuania. The following tasks were raised in order to achieve the aim: to assess the conformity of functions performed by Lithuanian OHS services with ILO Convention No. 161; to identify functions of OHS services in energy sector companies in Lithuania; to identify and evaluate the conformity of human resources of OHS services in energy sector companies in Lithuania with the legislation of the Republic of Lithuania. Conformity of functions of Lithuanian OHS services with ILO Convention No. 161 was assessed on the basis of 11 functions regulated in the Convention. Functions and human resources of the Occupational health and safety services were detected having performed a questionnaire survey in November – December 2009. Questionnaire was drawn up following the guidelines of the World Health Organization (WHO): Regional Guidelines for the Development of Healthy Workplaces and Basic Occupational Health Services. During the research a questionnaire survey was performed, which... [to full text]

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Xu, Jia Cheng. "Evaluation of Thoracic Injury Risk of Heavy Goods Vehicle Occupants during Steering Wheel Rim Impacts to Different Rib Levels." Thesis, KTH, Medicinteknik och hälsosystem, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-266357.

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The interior of heavy goods vehicles (HGVs) differs from passenger cars. Both the steering wheel and the occupant are positioned differently in a HGV and increases the risk of steering wheel rim impacts. Such impact scenarios are relatively unexplored compared to passenger car safety studies that are more prevalent within the field of injury biomechanics. The idea with using human body models (HBMs) is to complement current crash test dummies with biomechanical data. Furthermore, the biofidelity of a crash dummy for loading similar to a steering wheel rimimpact is relatively unstudied and especially to different rib levels. Therefore, the aim with this thesis was to evaluate HGV occupant thoracic response between THUMS v4.0 and Hybrid III (H3) during steering wheel rim impacts with respect to different rib levels (level 1-2, 3-4, 6-7, 7-8, 9-10) with regards to ribs, aorta, liver, and spleen. To the author’s best knowledge, use of local injury risk functions for thoracic injuries is fairly rare compared to the predominant usage of global injury criteria that mainly predicts the most commonthoracic injury risk, i.e. rib fractures. Therefore, local injury criteria using experimental test datahave been developed for the ribs and the organs. The measured parameters were chest deflectionand steering wheel to thorax contact force on a global level, whilst 1st principal Green-Lagrangestrains was assessed for the rib and the organ injury risk. The material models for the liver and the spleen were remodelled using an Ogden material model based on experimental stress-strain data to account for hyperelasticity. Rate-dependency was included by iteration of viscoelastic parameters. The contact modelling of the organs was changed from a sliding contact to a tied contact to minimize unrealistic contact separations during impact. The results support previous findings that H3 needs additional instrumentation to accurately register chest deflection for rib levels beyond its current range, namely at ribs 1-2, 7-8, and 9-10. For THUMS, the chest deflection were within reasonable values for the applied velocities, but there were no definite injury risk. Fact is, the global injury criteria might overpredict the AIS3 injury risk (rib fractures) for rib level 1-2, 7-8, and 9-10. The rib strains could not be correlated with the measured chest deflections. This was explained by the unique localized loading characterized by pure steering wheel rim impact that mainly affected the sternum and the rib cartilage while minimizing rib deformation. The organ strains indicate some risk of rupture where the spleen deforms the most at rib levels 3-4 and 6-7, and the liver and the aorta at rib levels 6-7 and 7-8. This study provides a framework for complementing H3 with THUMS for HGV occupant safety with emphasis on the importance of using local injury criteria for functional injury prediction, i.e. prediction of injury risk using parameters directly related to rib fracture or organ rupture. Local injury criteria are thus a powerful safety assessment tool as it is independent on exterior loading such as airbag, steering wheel hub, or seat belt loading. It was noticed that global injury criteria with very localized impacts such as rim impacts have not been studied and will affect rib fracture risk differently than what has been studied using airbag or seat belt restraints. However, improvements are needed to accurately predict thoracic injury risk at a material level by finding more data for the local injury risk functions. Conclusively, it is clear that Hybrid III has insufficient instrumentation and is in need of upgrades to register chest deflections at multiple rib levels. Furthermore, the following are needed: better understanding of global injury criteria specific for HGV occupant safety evaluation, more data for age-dependent (ribs) and rate-dependent (organs) injury risk functions, a tiebreak contact with tangential sliding for better organ kinematics during impacts, and improving the biofidelity of the material models using data from tissue level experiments.
Förarmiljön i lastbilar gentemot personbilar är annorlunda, i detta kontext med avseende på främst ratt- och förarposition som ökar risken för islag med rattkransen för lastbilsförare. Sådana islag är relativt outforskat jämfört med passiv säkerhet för personbilar inom skadebiomekaniken. Tanken bakom användning av humanmodeller är att komplettera nuvarande krockdockor med biomekanisk information. Dessutom är biofideliteten hos en krockdocka vid rattislag relativt okänt, speciellt vid olika revbensnivåer. Därför är målet med detta examensarbete att undersöka thoraxresponsen hos en lastbilsförare genom att använda THUMS v4.0 och Hybrid III (H3) under rattislag med avseende på revbensnivåer (nivå 1-2, 3-4, 6-7, 7-8, och 9-10) och revben, aorta, lever, och mjälte. Enligt författaren verkar användning av lokala riskfunktioner för thoraxskador relativt ostuderat jämfört med den övervägande användningen av globala riskfunktioner som huvudsakligen förutser den mest vanligt förekommande thoraxskadan, nämligen revbensfrakturer. Därför har lokala riskfunktioner skapats för revben och organ, baserat på experimentell data. Uppmätta parametrar var bröstinträngning och kontaktkraft mellan ratt och thorax på global nivå, medan första Green-Lagrange huvudtöjningen användes för att evaluera skaderisken för revben och organ. Materialmodeller för lever och mjälte ommodellerades baserat på experimentell spänning-töjningsdata med Ogdens materialmodell för att ta hänsyn till hyperelasticitet. Töjningshastighetsberoendet inkluderades genom att iterera fram viskoelastiska parametrar. Kontaktmodellering av organ gjordes genom att ändra från glidande kontakt till en låsande kontakt för att minimera orealistisk kontaktseparation under islagsfallen. Resultaten stödjer tidigare studier där H3 visat sig behöva ytterligare givare för att noggrannt kunna registrera bröstinträngning vid olika revbensnivåer bortom dess nuvarande räckvidd, nämligen vid revben 1-2, 7-8, och 9-10. Uppmätt bröstinträngning i THUMS var rimliga för hastighetsfallen men gav inte någon definitiv risk för skada. Faktum är att de globala riskfunktionerna kan överskatta AIS3 risken vid revben 1-2, 7-8, och 9-10. Revbenstöjningarna kunde inte korreleras med bröstinträngningarna. Detta kunde förklaras genom de unika lastfallen som karakteriseras av rena rattislag som främst påverkar sternum och revbensbrosk som i sin tur minimerar deformation av revben. Organtöjningarna indikerar på någon risk för ruptur där mjälten deformerar som mest vid revben 3-4 och 6-7, medan för både levern och aortan sker det vid revben 6-7 och 7-8. Denna studie presenterar ett sätt att komplettera H3 med THUMS inom passiv säkerhet för lastbilsförare med fokus på lokala riskfunktioner för funktionell skadeprediktering dvs. prediktering av skaderisken med hjälp av parametrar som är direkt relaterat till revbensfraktur eller organruptur. Lokala riskfunktioner utgör en kraftfull säkerhetsbedömning som är oberoende av externa lastfall som t.ex. airbag, rattcentrum, eller bälteslast. I denna studie noterades det att de globala riskkriterierna inte har undersökts med väldigt lokala islag som rattislagen utgör och kommer därför att påverka risken för revbensfraktur annorlunda gentemot vad som har studerat, t.ex. airbag eller bältelast. Däremot behövs det mer data för de lokala riskkriterierna för att kunna prediktera thoraxskaderisken med ökad noggrannhet. Avslutningsvis, det är tydligt att Hybrid III har otillräckligt med givare och behöver förbättras för att kunna registrera bröstinträngning vid flera revbensnivåer. Vidare behövs följande: bättre förståelse för globala riskfunktioner anpassat inom passiv säkerhet för lastbilsförare, mer data för åldersberoende (revben) och töjningshastighetsberoende (organ) riskfunktioner, en ”tiebreak” kontakt med tangientiell glidning för bättre organkinematik, och ökad biofidelitet av materialmodeller genom att använda data från vävnadsexperiment.

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Drlík, Michal. "Metodika vývoje a validace softwaru pro bezpečnostní části řídících systémů v divadelní technice." Doctoral thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2019. http://www.nusl.cz/ntk/nusl-409080.

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This thesis describes what the theatre is and what types of machinery can be found there. Then the issue of stage technical machinery is presented into the czech context, respectively into the Europian legislation with the emphasis on the technical norms usage, which are necessary to fulfil in order to reach this aim. In the next part of the thesis is made the analysis of control systems, which are used in the stage technics with the emphasis on the functionality of these control systems, since this functionality determines number and range of possible danger and dangerous events, later on. These dangerous situations are named and specified in detail, thereby their existence, importance and necessity of solution is being emphasized. There is also a possible solution outlined that these dangerous events can be solved in many cases by using of these programmable systems relating to the safety, thereby safety functions realized by these functions. Then the single steps are described into V-model with appropriate documents of these V-model steps. Outcome of this thesis will be suggested model of method and its development and software validation for programmable and control systems in theatre technology.

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Andersson, Robin, and Robert Timalm. "Development and simulation of a safety bracket for a safety system." Thesis, Tekniska Högskolan, Jönköping University, JTH, Industriell produktutveckling, produktion och design, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-49324.

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This thesis report aims to help the client developing their new product. The new product to be developed is a safety bracket for a safety system. The safety bracket connects different parts which create the safety system and it should be able to withstand impacts from moving objects. The client has a set of requirements that needs to be addressed during the product development process. One of the most important requirements that must be fulfilled is the given impact energy that the safety bracket must withstand. The methodology used during this thesis work is the product development processes (PDP). The product development process is used to find concepts that have the potential to answer the research questions and to fulfil the requirements. Some methods used in the product development process are brainstorming, brainwriting and combining working principles. The concepts were evaluated with a combination of Pugh´s matrix and weighting matrix. The three best concepts were selected for further development and tested with FEA simulation with Abaqus CAE. The impact simulation gave indications if the concepts could handle the impact energy and if they could fulfil the requirements. All three concepts could withstand the impact energy based on the simulations and most of the requirements could be fulfilled. The concepts with thinner profile walls had a reduction in stress and an increase in impact duration, where the kinetic energy is distributed throughout the impact. A protective shell helps with the reduction of stress and the energy absorption during the impact simulation.

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Düsing, Christa, and David Prust. "Supplementary failure mode and effect analysis (FMEA) for safety application standards DIN EN ISO 13849 safety function-fmea." Technische Universität Dresden, 2020. https://tud.qucosa.de/id/qucosa%3A71272.

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In the automotive industry, the Safety Function-FMEA according to ISO 26262 and its application to functional safety relevant systems is a well-established process in the form of Automotive Safety Integrity Levels (ASILs). These represent the failure mitigation that must be applied to ensure an acceptable residual risk of malfunctioning behaviour. The DIN EN ISO 13849 (ISO 13849) already describes a process to reduce risks for machines which starts with a Hazard And Risk Analysis (HARA) as described in DIN EN ISO 12100 and concludes with the Safety Requirements Specification (SRS). The SRS is a functional and technical safety concept defining requirements and guidelines to make sure the design conforms to defined safety goals. ISO 13849 lists important faults and failures for various technologies. The defined Safety Functions (SFs) can be classified in corresponding categories that lead to the particular hardware/system structure. This applies to mechatronic systems consisting of at least one sensor, one control unit and one actuator to monitor the system and effect a response in case of failure. Compared to the methods described in ISO 13849, the Safety Function-FMEA allows systematic identification of additional failures resulting from combinations of effects, rather than only listing the main failure causes. Based on the complexity of the machines it is highly recommended to perform a Safety Function-FMEA as a complementary method to assess and improve the overall safety of machinery.

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Zvolánková, Kateřina. "Zlepšení podnikových procesů zajišťování bezpečnosti produktů." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2020. http://www.nusl.cz/ntk/nusl-417961.

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The diploma thesis devotes to the process of ensuring functional safety of products in Bosch Rexroth Brno, which deals with industrial hydraulic systems. The first part introduces the basic legislative regulations concerning product safety and describes selected standards relevant to this thesis. The second part focuses on Bosch Rexroth and the current state in the field of ensuring functional safety of their products. It also includes a description of the functional safety solution of a specific project – a hydraulic try-out press. At the end of the thesis, improvements to the process of ensuring functional safety in response to the identified shortcomings are proposed.

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Björkman, Peter. "Probabilistic Safety Assessment using Quantitative Analysis Techniques : Application in the Heavy Automotive Industry." Thesis, Uppsala universitet, Institutionen för informationsteknologi, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-163262.

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Safety is considered as one of the most important areas in future research and development within the automotive industry. New functionality, such as driver support and active/passive safety systems are examples where development mainly focuses on safety. At the same time, the trend is towards more complex systems, increased software dependence and an increasing amount of sensors and actuators, resulting in a higher risk associated with software and hardware failures. In the area of functional safety, standards such as ISO 26262 assess safety mainly focusing on qualitative assessment techniques, whereas usage of quantitative techniques is a growing area in academic research. This thesis considers the field functional safety, with the emphasis on how hardware and software failure probabilities can be used to quantitatively assess safety of a system/function. More specifically, this thesis presents a method for quantitative safety assessment using Bayesian networks for probabilistic modeling. Since the safety standard ISO 26262 is becoming common in the automotive industry, the developed method is adjusted to use information gathered when implementing this standard. Continuing the discussion about safety, a method for modeling faults and failures using Markov models is presented. These models connect to the previous developed Bayesian network and complete the quantitative safety assessment. Furthermore, the potential for implementing the discussed models in the Modelica language is investigated, aiming to find out if models such as these could be useful in practice to simplify design work, in order to meet future safety goals.

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Böhlander, Marcus. "Design and Safety Analysis ofEmergency Brake System forAutonomous Formula Car : In Reference to Functional Safety ISO 26262." Thesis, KTH, Fordonsdynamik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-243285.

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The engineering competition Formula Student has introduced a Driverless Vehicle (DV)class, which requires the students to develop a car that can autonomously make its wayaround a cone track. To ensure the safety of such a vehicle, an Emergency Brake System(EBS) is required. The EBS shall ensure transition to safe state for detection of a singlefailure mode. This thesis work covers the design of the EBS for KTH Formula Student(KTH FS).Due to the safety critical character of this system, the software part of the EBS, calledEBS Supervisor, has been analyzed in accordance with the safety standard ISO 26262 tosee if an improved safety could be achieved. The analysis has been perform according toPart 3: Concept phase of ISO 26262 with an item definition, Hazard Analysis and RiskAssessment (HARA), Functional Safety Concept (FSC) and Technical Safety Concept(TSC).The result of the analysis showed that the EBS Supervisor requires extensive redundanciesin order to follow ISO 26262. This includes an additional CPU as well as signal checksof inputs and outputs. Due to limited resources in terms of money and time within theKTH FS team, these redundancies will not be implemented. The process of working withthe safety standard did however inspire an increased safety mindset.
Ingenjörstävlingen Formula Student har introducerat en förarlös tävlingsklass (eng:Driverless Vehicle) som innebär att studenterna ska utveckla en bil som autonomt kan tasig runt en konbana. För att försäkra sig om säkerheten för ett sådant fordon krävs ettnödbromssystem (eng: Emergency Brake System (EBS)). EBS:en skall försäkra att enövergång till ett säkert tillstånd sker då ett singulärt fel upptäcks. Det här examensarbetetbehandlar designen av EBS:en för KTH Formula Student.På grund av den säkerhetskritiska karaktären hos detta system har mjukvarudelen avEBS:en, kallad EBS Supervisor, blivit analyserad utifrån säkerhetsstandarden ISO 26262för att se om en förbättrad säkerhet kunde uppnås. Analysen har blivit genomfördenligt Del 3: Konceptfas av ISO 26262 med item definition, Hazard Analysis and RiskAssessment, Functional Safety Concept och Technical Safety Concept.Resultatet av analysen visade att EBS Supervisor kräver omfattande redundanser föratt uppfylla ISO 26262. Detta inkluderar en extra CPU såväl som kontroller av inochutsignaler. På grund av begränsade resurser i form av pengar och tid inom KTHFS, valdes dessa redundanser att inte implementeras. Processen av att arbeta medsäkerhetsstandarden har dock inspirerat ett ökat säkerhetstänk.

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Li, Tianpei. "Fault Diagnosis for Functional Safety in Electrified and Automated Vehicles." The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1587583790925718.

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Piper, Thorsten [Verfasser], Neeraj [Akademischer Betreuer] Suri, and Roman [Akademischer Betreuer] Obermaisser. "Assessing and Enhancing Functional Safety Mechanisms for Safety-Critical Software Systems / Thorsten Piper. Betreuer: Neeraj Suri ; Roman Obermaisser." Darmstadt : Universitäts- und Landesbibliothek Darmstadt, 2015. http://d-nb.info/1111113556/34.

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Šimoník, Martin. "Funkční bezpečnost snímačů tlaku BD SENSORS, s.r.o." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2015. http://www.nusl.cz/ntk/nusl-221099.

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This master thesis examines the functional safety of the pressure sensor XMP i which is produced by BD SENSORS Company. The aim of this thesis is the demonstration of compliance of the pressure sensor XMP I with functional safety integrity level SIL3 requirements. The thesis is divided into three parts. The first part deals with the concept of functional safety, defines the basic concepts of functional safety, compares the approaches of functional safety according to selected standards and provides a general procedure for the functional safety determination. The second part deal with technical systems reliability defines reliability indicators and describes selected types of reliability analysis used in practice, especially the FMEA/FMECA analysis. Third part deals with the reliability analysis of the sensor XMP i and with evaluation of results.

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Wang, Rui. "Confidence in safety argument - An assessment framework based on belief function theory." Thesis, Toulouse, INSA, 2018. http://www.theses.fr/2018ISAT0013/document.

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Les arguments de sécurité sont couramment utilisés pour montrer que des efforts suffisants ont été faits pour atteindre les objectifs de sécurité. Ainsi, la sécurité du système est souvent justifiée par l'évaluation des arguments de sécurité. L'évaluation de tels arguments repose généralement sur l’avis d’experts sans s’appuyer sur des outils ou des méthodes dédiés. Ceci pose des questions sur la validité des résultats. Dans cette thèse, une approche quantitative est proposée, basé sur la théorie de Dempster-Shafer (théorie D-S) pour évaluer notre confiance dans les arguments de sécurité. Cette approche gère le problème à travers les aspects suivants: 1) Définition formelle de la confiance dans les arguments basée sur la théorie D-S; 2) Développement de règles d'agrégation des paramètres de confiance; 3) Proposition d'un cadre d'évaluation quantitatif des arguments de sécurité. Une application dans le domaine ferroviaire conduit à l'estimation des paramètres du cadre par une enquête auprès d'experts en sécurité
Safety arguments, also called Safety Cases, are commonly used to present that adequate efforts have been made to achieve the safety goals. Thus, the system safety is often justified through assessing the safety arguments. The assessment of such arguments is usually implemented by experts without any dedicated tool or method. This leads to a questionable validity of the results. In this thesis, a quantitative framework is proposed based on Dempster-Shafer theory (D-S theory) to assess our confidence in Safety Cases. This framework manages the issue in following aspects: 1) Formal definition of confidence in arguments based on D-S theory; 2) Development of confidence aggregation rules; 3) Proposition of a quantitative assessment framework of safety arguments. An application in railway domain realises the parameter estimation of the framework by a survey with safety experts

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Ortman, Victor, and Petter Gradin. "Development of a Collision Avoidance Truck System from a Functional Safety Perspective." Thesis, Linköpings universitet, Institutionen för systemteknik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-71854.

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ISO 26262 is a functional safety standard under development at the time of this thesis. It is an adaptation of the functional safety standard IEC 61508, aimed at development of automotive electrical/electronic systems. The version of ISO-26262 that was used and discussed in this thesis is the final draft released in January 2011. In this thesis, a subset of ISO-26262 is applied in the development of a safety critical driver assistance system for a Scania vehicle. The parts of ISO-26262 that are treated are Part 3: Concept phase, Part 4: Product development at the system level and Part 5: Product development at the hardware level. Throughout the thesis we evaluate ISO-26262 and report our experience of working with it. The driver assistance system under development, which ISO-26262 is applied to, is Collision Avoidance by Steering, a system that aims to avoid or mitigate rear-end collisions with vehicles in front by automatic steering of the vehicle.

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Sternudd, Patrik. "Unambiguous Requirements in Functional Safety and ISO 26262: Dream or Reality?" Thesis, Uppsala universitet, Institutionen för informationsteknologi, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-164883.

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Oscarsson, Joakim. "Functional Safety in Co-operative Driving using Systems-Theoretic Process Analysis." Thesis, KTH, Maskinkonstruktion (Inst.), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-201094.

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Kooperativ körning är fenomenet av uppkopplade väg fordon som utbyter information för att uppnå säkrare och mer effektiva trafiksituationer. Det är en invecklad kontext som ger nya synvinklar på området funktionell säkerhet. Det kan automatiseras, och då autonoma fordon är beroende av pålitlig information för att kunna fatta beslut, så uppstår frågan med tillit till datamottagen genom kooperativa körningskanaler. Även bortsatt från området datasäkerhet, finns fortfarande en risk att brister i andra fordon kan orsaka att inkommande kommunikationssignaler ej blir trovärdiga. I det här examensarbetet visas att antaganden om nivån av tillförlitlighet till data från externa fordon kan ha en signifikant påverkan på den slutgiltiga arkitekturen. Det visas också att det varken att fullt lita på, eller att inte alls lita på data mottagen genom kooperativa körningskanaler, är optimalt när hänsyn tas till säkerhet, nyttjande av kommunikationsmöjligheter och kostnader. På grund av komplexiteten i kooperativ körning utförs analyserna med den nya och tillsynes lovande metoden System-teoretisk process analys (STPA). För tillfället är det praxis inom fordonsindustrin att för funktionell säkerhet rätta sig till standarden ISO 26262, som inte ger någon naturlig väg att implementera STPA. Därför presenterar detta examensarbete en utvecklingsprocess som nyttjar fördelarna med STPA och rättar sig efter ISO 26262 standarden. STPA har störst potential under produktutveckling vid system design, men även andra användningsområden har identifierats. STPA är en modern, generell analysmetod som aldrig tidigare används i kontexten kooperativ körning. Därför inleder detta examensarbete med att validera dess tillämpbarhet i denna specifika kontext. Utvärderingen utförs genom en studie av ett verkligt fall, kopplat till KTHs deltagande i Grand Cooperative Driving Challenge - en tävling av i-GAME, menat att snabba på implementeringen av kooperativ körning i Europa. Metodens validitet i kontexten styrks av fler än en analytiker, utvecklingsteamet för kooperativ körning på KTH, en klients godkännande av resultat, samt av akademisk granskning.
Co-operative driving is the phenomenon of connected road vehicles exchanging information to achieve safer and more efficient traffic. It is a convoluted context, which gives the topic of functional safety new complex angles. It can be automated, and as autonomous vehicles are dependent on reliable information for decision making, the issue of trusting data received over co-operation communication channels is raised. Disregarding the topic of security, there is still the possibility of failures in external vehicles causing incoming transmissions to be untrustworthy. In this thesis, it is shown that premises regarding levels of external trust can have significant impacts on the final architecture. It is also shown that neither fully trusting, nor not trusting data received over co-operation communication channels is the best option, when considering safety, usage of communication potential and cost. Because of the complexity of co-operative driving, the analyses are performed using the new and promising method of Systems-Theoretic process analyses (STPA). The current best practice of automotive functional safety is to comply with the domain specific ISO 26262 standard, which does not provide a natural way of implementing STPA. Therefore, this thesis also presents a development process which utilises the benefits of STPA, while complying to the ISO 26262 standard. STPA has the greatest potential during the product development at system level, though other uses have also been identified. STPA is a generic analysis method, which has previously not been used in the context of cooperative driving. This thesis therefor begins by validating the applicability of STPA in this specific context. The evaluation is performed using a real world case study connected to KTH’s participation in the Grand Cooperative Driving Challenge - a competition by i-GAME to speed up the implementation of co-operative driving in Europe. The validity of the method when applied to this context is strengthened by multiple analysts, the KTH co-operative driving development team, client approval of results and academic reviews.

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Kamtekar, Darshana M. "Implementation of functional safety in a robotic manufacturing cell using IEC 61508 standard and Siemens technology /." Online version of thesis, 2009. http://hdl.handle.net/1850/11174.

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Gibbons, Joshua Daniel. "Intersection Safety Analysis Methodology for Utah Roadways." BYU ScholarsArchive, 2018. https://scholarsarchive.byu.edu/etd/6838.

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Roadway safety continues to be a priority for the Utah Department of Transportation (UDOT) Traffic and Safety Division. UDOT has participated in and managed several research projects in recent years to determine the roadway segments of highest safety concern in the state. This research has provided UDOT with more tools to assist in safety project prioritization. Researchers in Department of Civil and Environmental Engineering at Brigham Young University (BYU) have worked with UDOT and the Statistics Department at BYU to create two network screening statistical tools called the Utah Crash Prediction Model (UCPM) and the Utah Crash Severity Model (UCSM) to analyze roadway segment safety. The Roadway Safety Analysis Methodology (RSAM) was developed as a process to run these segment models. Because a significant portion of crashes occur at intersections, there is a need to analyze roadway safety specifically at intersections. This research focuses on the development of the Utah Intersection Crash Prediction Model (UICPM) and the Intersection Safety Analysis Methodology (ISAM). The UICPM is a Bayesian generalized linear model that determines crash distributions for each intersection based on roadway characteristics and historical crash data. The observed number of crashes at each intersection is compared with the crash distribution, and a percentile value is calculated as the probability that the number of crashes occurring at an intersection in a particular year is less than or equal to the average annual number of crashes. A high percentile value indicates that more crashes were observed than expected and the intersection is a hot spot and should be considered for safety improvements. All intersections are ranked at the state, UDOT Region, and county levels based on the percentile value, the higher ranks having higher percentile values. The ISAM is the three-step process that was developed to execute the UICPM. The first step is to prepare the model input by formatting and combining the roadway characteristics and crash data files. Crashes are assigned to intersections if they fall with the functional area of an intersection. Due to data limitations, the ISAM is currently being used only for intersections of at least two state routes. It is anticipated that, as more data are made available, the ISAM will function properly for intersections of non-state routes as well. The second step is to execute the UICPM using the R GUI tool and R software. The third step is to create a two-page Intersection Safety Analysis Report (ISAR) for intersections of interest and maps of the state, UDOT Regions, and counties with the model results. Parts of the ISARs are auto-generated and the rest is entered manually by an analyst. The two-page ISARs will be used by UDOT Regions to prioritize intersection safety projects in their respective areas.

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Sadiq, Mazhar. "Modeling the Non-functional Requirements in the Context of Usability, Performance, Safety and Security." Thesis, Blekinge Tekniska Högskola, Avdelningen för programvarusystem, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-3246.

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Requirement engineering is the most significant part of the software development life cycle. Until now great emphasis has been put on the maturity of the functional requirements. But with the passage of time it reveals that the success of software development does not only pertain to the functional requirements rather non-functional requirements should also be taken into consideration. Among the non-functional requirements usability, performance, safety and security are considered important. Further it reveals that there exist so many modeling and testing techniques for functional requirements but the area of non-functional requirements is still deprived off. This is mainly due to difficulty, diversity in nature and hard to express for being domain-specific. Hence emphasis is put to the development of these models or testing techniques. While developing these models or testing techniques it is found that all the four areas of usability, performance, safety and security are not only closely related but rather depend on one another up to some extent. This meant that they all should be tackled while keeping into consideration of the related from among them. For the purpose it seemed necessary to collect in one artefact all the available modeling and testing techniques related to the four core areas of non-functional requirements may be collected and compared. This work at first provides an understanding of the problem domain while describing aspects of the non-functional requirements. Then possibly the available related models or testing techniques are collected and discussed. Finally in the last they are compared with respect to diversified aspects.

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Woltjer, Rogier. "Functional Modeling of Constraint Management in Aviation Safety and Command and Control." Doctoral thesis, Linköping : Department of of Computer and Information Science, Linköping University, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-17639.

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Dissertations / Theses on the topic 'Safety functions'

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