A Human Situation Awareness Support System to Avoid Technological Disasters

In many complex technological systems, accidents have primarily been attributed to human error. In the majority of these accidents the human operators were striving against significant challenges. They have to face data overload, the challenge of working with a complex system and the stressful task of understanding what is going on in the situation. Therefore, to design and implement complex technological systems where the information flow is quite high, and poor decisions may lead to serious consequences, Situation Awareness (SA) should be appropriately considered. A level 1 SA is highly supported in these systems through the various heterogeneous sensors and signal-processing methods but, for levels 2 and 3 there is still a need for concepts and methods. This work develops a system called the Human Situation Awareness Support System (HSASS) that supports the safety operators in an ever increasing amount of available risky status and alert information. The proposed system includes a new dynamic situation assessment method based on risk, which has the ability to support the operators understanding of the current state of the system, predict the near future, and suggest appropriate actions. The proposed system does not control the course of action and allows the human to act at his/her discretion in specific contexts

The effect of educational interventions based on synectics and 5E patterns on students' academic performance in geometry

Background and Objectives: Educating creative people is one of the important goals of educational systems. Undoubtedly, using educational models appropriate to educational content provides a suitable platform for achieving this goal. Innovative and 5 E patterns lead to increasing student creativity. In the innovation model, the student tries to look at the problem with a new perspective and turn it into a familiar problem by analogy and simile. In the 5E inclusive model, the student discovers relationships, solutions, and concepts through participation in a variety of activities. The aim of the present study was to investigate the effect of educational interventions based on innovation and 5E patterns on the academic performance of 9th grade students’ geometry. Methods: The research method was quasi-experimental in which pre-test, post-test design with control group was used. From the statistical population of 9th grade female students of Tehran public high schools, 3 classes, each class included 30 students as a sample, were selected by convenience sampling method. Then two classes were randomly selected as experimental groups of innovation and 5E and one class as control group. Data collection instruments included researcher-made performance tests tailored to innovation models and 5E, while the reliability and validity of these tests were assessed only for group 5E and the results were generalized for innovation groups and 5E. In order to collect the data, at the first phase, performance pre-tests based on the basic geometric concepts were administrated for innovation, 5E and control groups. Then, the content based on innovation and 5E patterns and the traditional method for innovation, 5E and control groups were implemented by the researcher in 8 sessions for 60 minutes in five consecutive weeks. Finally, the researcher-made post-test based on the geometric concepts was run for innovation, 5E and control groups. To analyze the data descriptive statistics (including mean and standard deviation) and inferential statistics containing Kolmogrov Smirnov (to check the normality of the data) and the ANOVA were used by SPSS statistical software. Findings: The results of the research in the descriptive statistics section showed that the mean difference between the pretest tests of the performance tests of the innovation groups with 2.73 and 5E with 3.16 compared to the control group with 0.42 showed significant differences. Also in the inferential statistics section, the results of the ANOVA test for pretests of the innovation, 5E and control groups indicated that the academic level of the students of innovation, 5E and control groups was the same. (0.05 <0.963). The results of the ANOVA test for post-tests of innovation, 5E, and control groups showed that 5E and innovation had a positive effect on the performance of 9th grade students in geometry. (0.00 <0.05). Conclusion: The use of innovation models and 5E led to students’ performance, so the educational system should emphasize the use of the methods that aim to increase interaction and cooperation between students. Therefore, it is suggested that the necessary training should be introduced in the curriculum of teacher training in order to get acquainted with and apply active teaching methods such as Baybi. Also, the content of textbooks should be organized based on active teaching methods, so that these methods can be taught and implemented in teaching materials. This research has been accompanied by limitations that may affect the generalizability of the research findings. Because it is not possible for the researcher to control disturbing variables such as intelligence and gender, these variables have some effect on the results. Also, due to time and space constraints and the issue of necessary permissions, this study was conducted only among 9th grade female students. Naturally, increasing the sample will lead to more accurate results.   ===================================================================================== COPYRIGHTS  ©2020 The author(s). This is an open access article distributed under the terms of the Creative Commons Attribution (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, as long as the original authors and source are cited. No permission is required from the authors or the publishers.  ====================================================================================

Formal Safety Assessment of a Marine Seismic Survey Vessel Operation, Incorporating Risk Matrix and Fault Tree Analysis

In maritime safety research, risk is assessed usually within the framework of formal safety assessment (FSA), which provides a formal and systematic methodology to improve the safety of lives, assets, and the environment. A bespoke application of FSA to mitigate accidents in marine seismic surveying is put forward in this paper, with the aim of improving the safety of seismic vessel operations, within the context of developing an economically viable strategy. The work herein takes a close look at the hazards in North Sea offshore seismic surveying, in order to identify critical risk factors, leading to marine seismic survey accidents. The risk factors leading to undesirable events are analysed both qualitatively and quantitatively. A risk matrix is introduced to screen the identified undesirable events. Further to the screening, Fault Tree Analysis (FTA) is presented to investigate and analyse the most critical risks of seismic survey operation, taking into account the lack of historical data. The obtained results show that man overboard (MOB) event is a major risk factor in marine seismic survey operation; lack of training on safe work practice, slippery deck as a result of rain, snow or water splash, sea state affecting human judgement, and poor communication are identified as the critical risk contributors to the MOB event. Consequently, the risk control options are focused on the critical risk contributors for decision-making. Lastly, suggestions for the introduction and development of the FSA methodology are highlighted for safer marine and offshore operations in general

Dynamic risk assessment using accident precursor data and Bayesian theory

To improve the safety of a process system, engineers use different methods to identify the potential hazards. Chemical processes involve handling of hazardous chemicals, which on release may potentially cause catastrophic consequences in terms of assets lost, human fatalities or injuries and loss of public confidence in the company. In spite of using endless end-of-the-pipe safety systems, tragic accidents such as BP Texas City refinery still occur. One of the main reasons of such rare but catastrophic event occurrences is lack of effective monitoring and modeling approaches that provide early warnings and help to prevent such events. Other reasons such as lack of criteria and/or assessment parameters and measures for detection of abnormal events may also have an important contribution. -- One of the most popular methods used in the industry today is quantitative risk assessment (QRA) which quantifies the risk associated with a particular process activity by determining the likelihood of occurrence of an unwanted event and the consequences involved. One of QRA's major disadvantages is its inability to update risk during the life of a process. As the process/system operates, abnormal events will result in incidents and near misses. These events are often called accident precursors. A conventional QRA process is unable to use the accident precursor information to revise the risk profile. -- Dynamic failure assessment is a new approach in process safety management, which enables the real time failure analysis of a process. Dynamic failure assessment has been used in the past by nuclear industries for accident likelihood estimation using accident precursors. Recently it has been successfully applied to process units to revise failure probabilities using incident and near miss data. In dynamic risk assessment, an extension of dynamic failure assessment, Bayesian and joint probability theories are used to develop a predictive failure model for a given process. As the process/system operates and generates incidents and near misses, the accident occurrence probability is predicted using accident precursors and later multiplied with consequences to quantify real time risk. -- In this thesis the dynamic risk assessment methodology is discussed in detail. First, potential accident scenarios are identified and represented in terms of an event tree, next, using the event tree and available failure data end state probabilities are estimated. Subsequently, using the available accident precursor data, safety system failure likelihood and event tree end state probabilities are revised. Finally, the updated probabilities are used in revising the risk profile of the process system. -- Application of this tool is demonstrated by two case studies. The first case study is the process facility of an offshore oil and gas platform where the risk profiles of process units are determined over time. In the second case study dynamic risk assessment is applied to the BP Texas City refinery in order to demonstrate the predictive abilities of the tool. Dynamic risk assessment demonstrates the importance of a learning and predictive tool in risk assessment by verifying significant changes in system failure frequency in comparison with the conventional QRA approach

Reliability analysis of spillway gate systems

The goal of this research is to develop a methodology to accurately determine the reliability of spillway gate systems particularly for spillways that experience harsh environmental conditions and prolonged periods of dormancy. The significance of this study lies in the fact that spillways are rarely in use and remain inactive for most of their service life. Components of emergency spillway gate systems spend the majority of their service life in a dormant state and are activated only during emergencies such as floods or load rejection or on a regular basis for inspection and testing. Also, most spillways are located in remote areas and are subjected to severe environmental conditions which can cause early degradation of components. Furthermore, components of old spillway gate systems are often custom made with no readily available spare parts and little information on the reliability of existing components. These characteristics are very different from those of the equipment used in an industrial setting making it difficult for traditional methods to deliver accurate estimates on the reliability of such systems. Therefore, the development of a methodology that is customized to such conditions and incorporates unique parameters and state-of-the-art reliability techniques can contribute greatly to the dam industry by ensuring the safe operation of spillway systems on demand. The first step in this approach is geared towards system modeling in which a reliability model is developed for the spillway gate system taking into account all components, their relative interactions, latent failures due to dormancy, environmental conditions and type and frequency of inspections and tests. The next step is to develop a quantitative approach to update the availability of the spillway gate system based on real time conditions after each inspection. In this step, a Condition Indexing (CI) approach is combined with dormant availability analysis to evaluate the changes in the state of the system in real time using CI data obtained at each inspection. This approach provides a tool for dam owners to convert qualitative and descriptive results obtained from inspections to an index used as a comparative measure to detect real time changes in the availability of spillway gate systems. Next, inspection and testing procedures of spillway gate systems are investigated to evaluate the effect of different types and frequencies on the reliability of various types of components and the entire system. Lastly, the optimum inspection and testing strategy is determined, minimizing system costs including costs related to inspection and testing and the consequences of failure while at the same time maintaining the availability of the spillway gate system above a predefined limit. Genetic algorithm and Creeping Random Search are used to solve this optimization problem. Using these methods the optimum interval for each type of test is determined and the minimum system cost is calculated based on the optimum intervals.This methodology is used to develop a software application that incorporates all of the above steps into a user friendly program. This software application has been developed for availability analysis of spillway systems and allows users to model complex systems, add inspection, tests and component replacement options to the system, determine the availability of the system as a function of service life and identify the optimum inspection and testing period based on unavailability limits and costs of inspections/tests vs. consequence of failure. This program can be used as a tool by dam owners to accurately determine the availability of custom spillways and to select optimal inspection and testing plans that contribute most to increase the availability of the system.Le but de cette recherche est de développer une méthodologie pour déterminer avec précision la fiabilité des évacuateurs de barrages en particulier pour les évacuateurs qui sont exposés à des conditions environnementales extrêmes et sont sujets à de longues périodes d'inactivité. L'importance de cette étude réside dans le fait que les évacuateurs sont rarement utilisés et demeurent inactifs pendant la majeure partie de leur durée de vie. Les composants des évacuateurs d'urgence passent la majorité de leur durée de vie dans un état de dormance et ne sont activés que lors de situations d'urgence telles que les inondations ou le rejet de la charge ou sur une base régulière pour l'inspection et des tests. En plus, la plupart des évacuateurs sont situés dans des régions avec accès limité et sont soumis à des conditions environnementales extrêmes qui peuvent causer une dégradation rapide des composants. En outre, les composants de vieux évacuateurs sont souvent fabriqués sur mesure, sans pièces de rechange facilement disponibles et peu d'informations sont disponibles sur leur fiabilité. Ces caractéristiques sont très différentes de celles des équipements utilisés dans un milieu industriel ce qui rend difficile l'application des méthodes d'analyse conventionnelles pour estimer la fiabilité de ces systèmes. Par conséquent, le développement d'une méthodologie qui est adaptée à ces conditions peut grandement contribuer à améliorer la sécurité de fonctionnement des évacuateurs sur demande.Cette étude vise à élaborer des procédures d'analyse de fiabilité qui considèrent les différentes fonctions et caractéristiques d'un évacuateur, y compris tous les composants électriques, mécaniques et structuraux. L'un des principaux défis dans cette évaluation est d'obtenir des estimations réalistes de la fiabilité de chaque composant. La première étape de cette approche est la modélisation du système en tenant compte de tous les composants, de leurs interactions, des défaillances latentes en période d'inactivité, des conditions environnementales, du type et de la fréquence des inspections et des essais. Une approche quantitative a été développée afin de mettre à jour la disponibilité des évacuateurs en fonction de l'état des composants suite à une inspection. Dans cette approche, une évaluation du niveau de fiabilité des composants est obtenue en fonction d'un diagnostic basé sur des observations qualitatives et quantitatives recueillies lors des inspections. Le modèle utilise cette information et intègre un modèle de détérioration afin de prédire la disponibilité des évacuateurs.Finalement, les procédures d'inspection et d'essais sur les évacuateurs sont étudiées pour évaluer leur effet sur la fiabilité en fonction de leurs caractéristiques, de leur efficacité et de leur fréquence pour les différents types de composants et l'ensemble du système. Enfin, une stratégie optimale pour les inspections et les essais est déterminée en minimisant une fonction de coûts qui intègre les coûts liés aux essais et inspections et les conséquences d'une défaillance et en respectant une norme minimale de fiabilité. Les algorithmes d'optimisation basés sur algorithme génétique et la recherche aléatoire sont utilisés pour résoudre ce problème. En utilisant ces méthodes, les fréquences optimales sont déterminées pour chaque type d'essai.Cette méthode est utilisée pour développer un logiciel qui intègre toutes les étapes ci-dessus. Ce logiciel a été développé spécifiquement pour l'analyse de la disponibilité des évacuateurs en utilisant la programmation orientée par objet et permet aux utilisateurs de modéliser des systèmes complexes, ajouter les inspections, les essais et les options de remplacement de composants du système, déterminer la disponibilité du système en fonction de la durée de vie, et identifier les fréquences d'inspection et d'essai optimales

Dynamic risk assessment using failure assessment and Bayesian theory

To ensure the safety of a process system, engineers use different methods to identify the potential hazards that may cause severe consequences. One of the most popular methods used is quantitative risk assessment (QRA) which quantifies the risk associated with a particular process activity. One of QRA's major disadvantages is its inability to update risk during the life of a process. As the process operates, abnormal events will result in incidents and near misses. These events are often called accident precursors. A conventional QRA process is unable to use the accident precursor information to revise the risk profile. To overcome this, a methodology has been proposed based on the work of Meel and Seider (2006). Similar to Meel and Seider (2006) work, this methodology uses Bayesian theory to update the likelihood of the event occurrence and also failure probability of the safety system. In this paper the proposed methodology is outlined and its application is demonstrated using a simple case study. First, potential accident scenarios are identified and represented in terms of an event tree, next, using the event tree and available failure data end-state probabilities are estimated. Subsequently, using the available accident precursor data, safety system failure likelihood and event tree end-state probabilities are revised. The methodology has been simulated using deterministic (point value) as well as probabilistic approach. This Methodology is applied to a case study demonstrating a storage tank containing highly hazardous chemicals. The comparison between conventional QRA and the results from dynamic failure assessment approach shows the significant deviation in system failure frequency throughout the life time of the process unit

The Impact of Bybee and Synectics Models on Creativity, Creative Problem-solving, and Students’ Performance in Geometry

The present study aimed to investigate the effect of Bybee and Synectics on creativity, creative problem-solving, and performance of ninth-grade students in geometry. The research method was quasi-experimental with pre-test, post-test, and control group. From the entire population of the ninth-grade female students of public high schools in Tehran, three intact classrooms were selected by the cluster sampling method, each consisting of 30 students. Then, two classes were randomly assigned to two experimental groups and one control group. In addition, research instruments included Abedi’s creativity test, Basadur’s problem-solving creative test, and a researcher-made geometry test .In order to collect data, at first, pre-tests of performance, creativity and creative solution were performed on the subjects. After performing the patterns in the groups, post-tests of performance, creativity and creative solution were performed on the subjects. Finally, descriptive (the mean and standard deviation) and inferential ANCOVA statistics were used to analyze the data by SPSS software. The findings indicated that using the patterns of Bybee and Synectics on students’ creativity, creative problem-solving, and performance in geometry were significantly more influential compared to traditional teaching methods .The use of educational patterns appropriate to the educational content will lead to the training of creative people

A Study on the Role of Drama in Learning Mathematics

Present educational systems needs modern strategies for teaching and learning. Mathematics education has to change for students in elementary schools. One of the modern strategies, it is drama activities. The drama is as empirical aspect of learning. The student may learn from what they are doing in drama. They are so active instead having a passive shape in drama, in fact, students are learning, finding experiences and new paths from drama as well. The students could find its capabilities, recommendations and strength-weakness points through the different drama. This study is looking to investigate the role of drama so that have a better understanding of mathematical concepts in Zahedan's girly elementary students (2011-12). This research is used on 36 three grade students through quasi-experiment method. The emerging results clearly showed that using drama in mathematics education has been better results against the traditional teaching. Then it seems that cited method is suitable for elementary students to learn mathematical concepts