H. Carter, Alexander Chan, Christopher Vinegar, J. Rupert
There is no debating the importance of data for artificial intelligence. The behavior of data-driven machine learning models is determined by the data set, or as the old adage states: “garbage in, garbage out (GIGO).” While the machine learning community is still debating which techniques are necessary and sufficient to assess the adequacy of data sets, they agree some techniques are necessary. In general, most of the techniques being considered focus on evaluating the volumes of attributes. Those attributes are evaluated with respect to anticipated counts of attributes without considering the safety concerns associated with those attributes. This paper explores those techniques to identify instances of too little data and incorrect attributes. Those techniques are important; however, for safety critical applications, the assurance analyst also needs to understand the safety impact of not having specific attributes present in the machine learning data sets. To provide that information, this paper proposes a new technique the authors call data hazard analysis. The data hazard analysis provides an approach to qualitatively analyze the training data set to reduce the risk associated with the GIGO.
{"title":"Proposing the Use of Hazard Analysis for Machine Learning Data Sets","authors":"H. Carter, Alexander Chan, Christopher Vinegar, J. Rupert","doi":"10.56094/jss.v58i2.253","DOIUrl":"https://doi.org/10.56094/jss.v58i2.253","url":null,"abstract":"There is no debating the importance of data for artificial intelligence. The behavior of data-driven machine learning models is determined by the data set, or as the old adage states: “garbage in, garbage out (GIGO).” While the machine learning community is still debating which techniques are necessary and sufficient to assess the adequacy of data sets, they agree some techniques are necessary. In general, most of the techniques being considered focus on evaluating the volumes of attributes. Those attributes are evaluated with respect to anticipated counts of attributes without considering the safety concerns associated with those attributes. This paper explores those techniques to identify instances of too little data and incorrect attributes. Those techniques are important; however, for safety critical applications, the assurance analyst also needs to understand the safety impact of not having specific attributes present in the machine learning data sets. To provide that information, this paper proposes a new technique the authors call data hazard analysis. The data hazard analysis provides an approach to qualitatively analyze the training data set to reduce the risk associated with the GIGO.","PeriodicalId":250838,"journal":{"name":"Journal of System Safety","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114954885","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Dustin S. Birch, Erika E. Miller, Thomas H. Bradley
Human Reliability Analysis (HRA) has found application within a diverse set of engineering domains, but the methods used to apply HRA are often complicated, time-consuming, costly to apply, specific to particular (i.e., nuclear) applications, and are not suitable for direct comparison amongst themselves. This paper proposes a Human Factors Hazard Model (HFHM), which builds an HRA method from the tools of Fault Tree Analysis (FTA), Event Tree Analysis (ETA), and a novel model of considering serial Human Error Probability (HEP) more relevant to psychomotor-intensive industrial and commercial applications such as manufacturing, teleoperation, and vehicle operation. The HEP approach uses Performance Shaping Factors (PSFs) relevant to human behavior, as well as specific characteristics unique to a system architecture and its corresponding operational behavior. The HFHM tool is intended to establish a common analysis approach, to simplify and automate the modeling of the likelihood of a mishap due to a human-system interaction during a hazard event. The HFHM is executed commercial software tools (MS Excel and SysML) such that trade and sensitivity studies can be conducted and iterated automatically. The results generated by the HFHM can be used to guide risk assessment, safety requirements generation and management, design options, and safety controls within the system design architecting process. Verification and evaluation of the HFHM through simulation and subject matter expert evaluation illustrate the value of the HFHM as a tool for HRA and system safety analysis in a set of key industrial applications.
{"title":"Human Reliability Analysis using a Human Factors Hazard Model","authors":"Dustin S. Birch, Erika E. Miller, Thomas H. Bradley","doi":"10.56094/jss.v58i2.251","DOIUrl":"https://doi.org/10.56094/jss.v58i2.251","url":null,"abstract":"Human Reliability Analysis (HRA) has found application within a diverse set of engineering domains, but the methods used to apply HRA are often complicated, time-consuming, costly to apply, specific to particular (i.e., nuclear) applications, and are not suitable for direct comparison amongst themselves. \u0000This paper proposes a Human Factors Hazard Model (HFHM), which builds an HRA method from the tools of Fault Tree Analysis (FTA), Event Tree Analysis (ETA), and a novel model of considering serial Human Error Probability (HEP) more relevant to psychomotor-intensive industrial and commercial applications such as manufacturing, teleoperation, and vehicle operation. The HEP approach uses Performance Shaping Factors (PSFs) relevant to human behavior, as well as specific characteristics unique to a system architecture and its corresponding operational behavior. The HFHM tool is intended to establish a common analysis approach, to simplify and automate the modeling of the likelihood of a mishap due to a human-system interaction during a hazard event. \u0000The HFHM is executed commercial software tools (MS Excel and SysML) such that trade and sensitivity studies can be conducted and iterated automatically. The results generated by the HFHM can be used to guide risk assessment, safety requirements generation and management, design options, and safety controls within the system design architecting process. Verification and evaluation of the HFHM through simulation and subject matter expert evaluation illustrate the value of the HFHM as a tool for HRA and system safety analysis in a set of key industrial applications.","PeriodicalId":250838,"journal":{"name":"Journal of System Safety","volume":"49 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131593747","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The ISO 26262: Functional Safety – Road Vehicles Standard has been the de-facto automotive functional safety standard since it was first released in 2011. With the introduction of complex driving automation systems, new standardization efforts to deal with safety of these systems have been initiated to address emerging gaps such as the human/automation roles and responsibilities in the presence/absence of the driver/user, the impact of the technological limitations and the verification and validation needs of automation systems to name a few. This paper highlights some of these gaps and introduces some of the latest developments in automotive safety standardization for driving automation systems.
{"title":"Review of the Latest Developments in Automotive Safety Standardization for Driving Automation Systems","authors":"R. Debouk","doi":"10.56094/jss.v58i2.252","DOIUrl":"https://doi.org/10.56094/jss.v58i2.252","url":null,"abstract":"The ISO 26262: Functional Safety – Road Vehicles Standard has been the de-facto automotive functional safety standard since it was first released in 2011. With the introduction of complex driving automation systems, new standardization efforts to deal with safety of these systems have been initiated to address emerging gaps such as the human/automation roles and responsibilities in the presence/absence of the driver/user, the impact of the technological limitations and the verification and validation needs of automation systems to name a few. This paper highlights some of these gaps and introduces some of the latest developments in automotive safety standardization for driving automation systems.","PeriodicalId":250838,"journal":{"name":"Journal of System Safety","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121985565","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Over many decades System Safety has evolved from a more re-active nature - learning from failures and improving – not really suitable for high consequence enterprises - to today’s more pro-active form. This is now based on better fundamental understanding, better assessment processes, better standards, more comprehensive analysis tools with better audit and regulation procedures. However, unlike ‘set educational subjects’ such as engineering, science, technology and mathematics, there are less opportunities for formal System Safety education and training in academia and elsewhere, even though system safety impacts on all aspects of life. One hopes that this will continue to be rectified. This leads us directly to the importance and value of this book, which gives a complete insight into the nature of what System Safety is all about, including its approaches, methodologies and tools, and which provides guidance on the successful application of a comprehensive, pro-active approach for ensuring safe system design.
{"title":"System Safety Bookshelf","authors":"Malcolm Jones","doi":"10.56094/jss.v58i1.214","DOIUrl":"https://doi.org/10.56094/jss.v58i1.214","url":null,"abstract":"Over many decades System Safety has evolved from a more re-active nature - learning from failures and improving – not really suitable for high consequence enterprises - to today’s more pro-active form. This is now based on better fundamental understanding, better assessment processes, better standards, more comprehensive analysis tools with better audit and regulation procedures. However, unlike ‘set educational subjects’ such as engineering, science, technology and mathematics, there are less opportunities for formal System Safety education and training in academia and elsewhere, even though system safety impacts on all aspects of life. One hopes that this will continue to be rectified. This leads us directly to the importance and value of this book, which gives a complete insight into the nature of what System Safety is all about, including its approaches, methodologies and tools, and which provides guidance on the successful application of a comprehensive, pro-active approach for ensuring safe system design.","PeriodicalId":250838,"journal":{"name":"Journal of System Safety","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123839227","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
As the space industry continues to innovate and new paradigms arise to challenge the status quo, human spaceflight is now perceived as safer and more accessible than ever before. This has led to a new line of thinking in which crewed launch vehicles should be reusable and reliable like commercial airplanes, forgoing the need for an abort system. This paper will counter that line of thought with an analysis of the spectrum of coverage historical crew abort systems provided during launch and use historical data from launch rate successes and failures to glean insight into what reliability in the human spaceflight industry can expect when designing the vehicles of the future. This historical launch vehicle reliability will then be compared to system safety standards used in the commercial aviation industry to understand if future designs truly need a crew abort system. Through this analysis, the rationale for why these crew abort systems have historically been used can be better understood.
{"title":"Difficulties with Replacing Crew Launch Abort Systems with Designed Reliability","authors":"S. Ryan","doi":"10.56094/jss.v58i1.216","DOIUrl":"https://doi.org/10.56094/jss.v58i1.216","url":null,"abstract":"As the space industry continues to innovate and new paradigms arise to challenge the status quo, human spaceflight is now perceived as safer and more accessible than ever before. This has led to a new line of thinking in which crewed launch vehicles should be reusable and reliable like commercial airplanes, forgoing the need for an abort system. This paper will counter that line of thought with an analysis of the spectrum of coverage historical crew abort systems provided during launch and use historical data from launch rate successes and failures to glean insight into what reliability in the human spaceflight industry can expect when designing the vehicles of the future. This historical launch vehicle reliability will then be compared to system safety standards used in the commercial aviation industry to understand if future designs truly need a crew abort system. Through this analysis, the rationale for why these crew abort systems have historically been used can be better understood.","PeriodicalId":250838,"journal":{"name":"Journal of System Safety","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133152628","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
One of the most prominent challenges in safety risk management of medical devices is the Benefit-Risk Analysis. This paper proposes a methodology to quantify benefits, thereby creating more consistency, and explainability in the evaluation of benefits and the benefit/risk ratio. Leveraging the guidance from the FDA, we define four Dimensions for appraising benefits. The product of the rankings of a benefit in all four Dimensions is used as a quantitative measure of a benefit. The quantitative score for the overall benefit of a medical device would be the sum of the scores of the individual benefits.
{"title":"Quantification of Benefits for Medical Devices","authors":"B. Elahi","doi":"10.56094/jss.v58i1.217","DOIUrl":"https://doi.org/10.56094/jss.v58i1.217","url":null,"abstract":"One of the most prominent challenges in safety risk management of medical devices is the Benefit-Risk Analysis. This paper proposes a methodology to quantify benefits, thereby creating more consistency, and explainability in the evaluation of benefits and the benefit/risk ratio. \u0000Leveraging the guidance from the FDA, we define four Dimensions for appraising benefits. The product of the rankings of a benefit in all four Dimensions is used as a quantitative measure of a benefit. \u0000The quantitative score for the overall benefit of a medical device would be the sum of the scores of the individual benefits.","PeriodicalId":250838,"journal":{"name":"Journal of System Safety","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124353656","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Simon Diemert, John Goodenough, Jeffrey J. Joyce, C. Weinstock
An assurance case for a critical system is valid for that system at a particular point in time, such as when the system is delivered to a certification authority for review. The argument is structured around evidence that exists at that point in time. However, modern assurance cases are rarely one-off exercises. More information might become available (e.g., field data) that could strengthen (or weaken) the validity of the case. This paper proposes the notion of incremental assurance wherein the assurance case structure includes both the currently available evidence and a plan for incrementally increasing confidence in the system as additional or higher quality evidence becomes available. Such evidence is needed to further reduce doubts engineers or reviewers might have. This paper formalizes the idea of incremental assurance through an argumentation pattern. The concept of incremental assurance is demonstrated by applying the pattern to part of a safety assurance case for an air traffic control system.
{"title":"Incremental Assurance Through Eliminative Argumentation","authors":"Simon Diemert, John Goodenough, Jeffrey J. Joyce, C. Weinstock","doi":"10.56094/jss.v58i1.215","DOIUrl":"https://doi.org/10.56094/jss.v58i1.215","url":null,"abstract":"An assurance case for a critical system is valid for that system at a particular point in time, such as when the system is delivered to a certification authority for review. The argument is structured around evidence that exists at that point in time. However, modern assurance cases are rarely one-off exercises. More information might become available (e.g., field data) that could strengthen (or weaken) the validity of the case. This paper proposes the notion of incremental assurance wherein the assurance case structure includes both the currently available evidence and a plan for incrementally increasing confidence in the system as additional or higher quality evidence becomes available. Such evidence is needed to further reduce doubts engineers or reviewers might have. This paper formalizes the idea of incremental assurance through an argumentation pattern. The concept of incremental assurance is demonstrated by applying the pattern to part of a safety assurance case for an air traffic control system.","PeriodicalId":250838,"journal":{"name":"Journal of System Safety","volume":"66 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116666855","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Software Control Category (SCC) denotes the degree of control autonomy, command and control authority, and redundant fault tolerance software has over hazardous system functions of safety-critical systems. The use of SCC for determining the software contribution to system risks is a unique feature of the MIL-STD-882E System Safety Standard. A lower SCC designation means that the software system has a greater control autonomy over hazardous system functions, whereas SCC 1 means complete autonomous control. Software with greater control autonomy over hazardous system functions require greater effort to assure reliability and safety. Correct assessment of the SCC level of hazardous system functions is crucial for optimizing the safety property of a system developed under budget, schedule, and resource constraints. Beyond the categorical definitions provided by the MIL-STD-882E Standard, there is little information on conducting an SCC assessment. To close this knowledge gap, we present an SCC assessment method. Our paper will describe in detail the process and rules for assessing SCC. For illustration, we apply our method to assess the SCC of several safety-significant functions of an automobile’s brake-assist system.
软件控制类别(Software Control Category, SCC)表示对安全关键系统的危险系统功能的控制自主性、指挥控制权限和冗余容错软件的程度。使用SCC来确定软件对系统风险的贡献是MIL-STD-882E系统安全标准的一个独特功能。较低的SCC标识意味着软件系统对危险系统功能具有更大的控制自主权，而SCC 1意味着完全自主控制。对危险系统功能具有更大控制自主权的软件需要更大的努力来确保可靠性和安全性。正确评估危险系统功能的SCC水平对于优化在预算、进度和资源限制下开发的系统的安全性能至关重要。除了MIL-STD-882E标准提供的分类定义之外，很少有关于进行SCC评估的信息。为了缩小这一知识差距，我们提出了一种SCC评估方法。本文将详细介绍SCC的评估过程和规则。为了说明，我们应用我们的方法来评估汽车制动辅助系统的几个安全重要功能的SCC。
{"title":"Assessing the Software Control Autonomy of System Functions in Safety-Critical Systems","authors":"V. Tran, V. Tran, L. Tran","doi":"10.56094/jss.v57i3.206","DOIUrl":"https://doi.org/10.56094/jss.v57i3.206","url":null,"abstract":"Software Control Category (SCC) denotes the degree of control autonomy, command and control authority, and redundant fault tolerance software has over hazardous system functions of safety-critical systems. The use of SCC for determining the software contribution to system risks is a unique feature of the MIL-STD-882E System Safety Standard. A lower SCC designation means that the software system has a greater control autonomy over hazardous system functions, whereas SCC 1 means complete autonomous control. Software with greater control autonomy over hazardous system functions require greater effort to assure reliability and safety. Correct assessment of the SCC level of hazardous system functions is crucial for optimizing the safety property of a system developed under budget, schedule, and resource constraints. Beyond the categorical definitions provided by the MIL-STD-882E Standard, there is little information on conducting an SCC assessment. To close this knowledge gap, we present an SCC assessment method. Our paper will describe in detail the process and rules for assessing SCC. For illustration, we apply our method to assess the SCC of several safety-significant functions of an automobile’s brake-assist system.","PeriodicalId":250838,"journal":{"name":"Journal of System Safety","volume":"69 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126680709","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We are currently confronted with the existential challenge of global warning. Because of its nature it is a challenge that confronts the entire globe both in terms of contributing factors and bearing the consequences. In both aspects there is an inevitable balance of responsibilities and consequences. In the former, some national entities are bigger contributors to the problem than others and in a similar manner some global areas suffer relatively more significant negative consequences. Another major challenge has been that of generating a better scientific understanding of the relationships between greenhouse gas emission, global warming, and the resulting environmental consequences. The remaining challenges that follow are how best to prevent or minimise greenhouse gas emissions, how to store them safety and how to mitigate the potential negative consequences. These are now global level responsibilities. At first sight this appears to be a problem restricted to big science, technology, and engineering alone in terms of finding more acceptable forms of energy production, as a counter to our current dependence on fossil fuels and that it might not be an area where system safety can play a prominent part. However, this is not the case, and this paper explores the system safety application possibilities, because all new developments require to be implemented in a safe manner.
{"title":"Global Warming and System Safety","authors":"Malcolm Jones","doi":"10.56094/jss.v57i3.205","DOIUrl":"https://doi.org/10.56094/jss.v57i3.205","url":null,"abstract":"We are currently confronted with the existential challenge of global warning. Because of its nature it is a challenge that confronts the entire globe both in terms of contributing factors and bearing the consequences. In both aspects there is an inevitable balance of responsibilities and consequences. In the former, some national entities are bigger contributors to the problem than others and in a similar manner some global areas suffer relatively more significant negative consequences. Another major challenge has been that of generating a better scientific understanding of the relationships between greenhouse gas emission, global warming, and the resulting environmental consequences. The remaining challenges that follow are how best to prevent or minimise greenhouse gas emissions, how to store them safety and how to mitigate the potential negative consequences. These are now global level responsibilities. At first sight this appears to be a problem restricted to big science, technology, and engineering alone in terms of finding more acceptable forms of energy production, as a counter to our current dependence on fossil fuels and that it might not be an area where system safety can play a prominent part. However, this is not the case, and this paper explores the system safety application possibilities, because all new developments require to be implemented in a safe manner.","PeriodicalId":250838,"journal":{"name":"Journal of System Safety","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130091092","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nothing is harder than to realize when you are living through history. For most of us, each day is pretty much like another. There is nothing historically remarkable about that. Occasionally, however, our lives are punctuated by events, both natural and man-made, that are apocalyptic and often (but not always) beyond our control – natural disasters, war, pestilence, and famine. These are the events that the historian must recognize. At this time, it is the COVID-19 pandemic that demands to be recorded by “his-story” so that posterity will know what we did right, and what we did wrong. This author has taken up the challenge of producing accurate, unbiased, comprehensive, technical annals of the global coronavirus pandemic that began in 2019. “The Delta Variant” is the third publication in this series. We are now near the end of the third year of the pandemic (summer/fall 2021). As predicted by this author, it has been a draconian year. Last year’s peak in the number of active cases was not a global maximum for the pandemic in the U.S., since this year the number of active cases has already surpassed it. Without knowing where the global maximum lies, no accurate predictions can be made about the magnitude and duration of this modern plague. The “Delta Variant” (δ-variant) of COVID-19 has greatly complicated efforts to combat the virus. The “anti-vaxxer” movement, uncontrolled migration of people into and within the U.S, and the relaxation of safety measures during the late spring and early summer in the U.S. also contributed difficulties. All of these problems were foreseen by the author and were discussed in the second paper (“Vaccine Safety”) of this series on the COVID pandemic. However, our biggest problem in the U.S. was an over confidence born of a natural summertime trough in the daily infection rate. We wanted to believe the infection was past, so we ignored the experience of India, and our administrators fueled our hopes with their words and actions. We believed because we wanted to believe – except for this author. So, what went wrong? What is a δ-variant, and why is it so dangerous? That will be the topic of this publication.
{"title":"Delta Variant","authors":"R. Zito","doi":"10.56094/jss.v57i3.204","DOIUrl":"https://doi.org/10.56094/jss.v57i3.204","url":null,"abstract":"Nothing is harder than to realize when you are living through history. For most of us, each day is pretty much like another. There is nothing historically remarkable about that. Occasionally, however, our lives are punctuated by events, both natural and man-made, that are apocalyptic and often (but not always) beyond our control – natural disasters, war, pestilence, and famine. These are the events that the historian must recognize. At this time, it is the COVID-19 pandemic that demands to be recorded by “his-story” so that posterity will know what we did right, and what we did wrong. This author has taken up the challenge of producing accurate, unbiased, comprehensive, technical annals of the global coronavirus pandemic that began in 2019. “The Delta Variant” is the third publication in this series. We are now near the end of the third year of the pandemic (summer/fall 2021). As predicted by this author, it has been a draconian year. Last year’s peak in the number of active cases was not a global maximum for the pandemic in the U.S., since this year the number of active cases has already surpassed it. Without knowing where the global maximum lies, no accurate predictions can be made about the magnitude and duration of this modern plague. The “Delta Variant” (δ-variant) of COVID-19 has greatly complicated efforts to combat the virus. The “anti-vaxxer” movement, uncontrolled migration of people into and within the U.S, and the relaxation of safety measures during the late spring and early summer in the U.S. also contributed difficulties. All of these problems were foreseen by the author and were discussed in the second paper (“Vaccine Safety”) of this series on the COVID pandemic. However, our biggest problem in the U.S. was an over confidence born of a natural summertime trough in the daily infection rate. We wanted to believe the infection was past, so we ignored the experience of India, and our administrators fueled our hopes with their words and actions. We believed because we wanted to believe – except for this author. So, what went wrong? What is a δ-variant, and why is it so dangerous? That will be the topic of this publication.","PeriodicalId":250838,"journal":{"name":"Journal of System Safety","volume":"70 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116975156","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：