[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"detail-sidebar-cat-0-en-105":3,"doc-seo-272828-105":59,"doc-detail-272828-en":130},{"code":4,"msg":5,"data":6},0,"success",[7,13,18,23,28,33,38,43,48,51,55],{"id":8,"doc_module":4,"doc_module_name":9,"category_name":10,"show_sort_weight":11,"slug":12},1,"Document","Story & Novel",90,"story-novel",{"id":14,"doc_module":4,"doc_module_name":9,"category_name":15,"show_sort_weight":16,"slug":17},2,"Literature",80,"literature",{"id":19,"doc_module":4,"doc_module_name":9,"category_name":20,"show_sort_weight":21,"slug":22},4,"Exam",70,"exam",{"id":24,"doc_module":4,"doc_module_name":9,"category_name":25,"show_sort_weight":26,"slug":27},5,"Comic",60,"comic",{"id":29,"doc_module":4,"doc_module_name":9,"category_name":30,"show_sort_weight":31,"slug":32},6,"Technology",50,"technology",{"id":34,"doc_module":4,"doc_module_name":9,"category_name":35,"show_sort_weight":36,"slug":37},7,"Healthcare",40,"healthcare",{"id":39,"doc_module":4,"doc_module_name":9,"category_name":40,"show_sort_weight":41,"slug":42},8,"Research & Report",30,"research-report",{"id":44,"doc_module":4,"doc_module_name":9,"category_name":45,"show_sort_weight":46,"slug":47},9,"Religion & Spirituality",20,"religion-spirituality",{"id":46,"doc_module":4,"doc_module_name":9,"category_name":49,"show_sort_weight":46,"slug":50},"World Cup","world-cup",{"id":52,"doc_module":4,"doc_module_name":9,"category_name":53,"show_sort_weight":52,"slug":54},10,"Lifestyle","lifestyle",{"id":56,"doc_module":4,"doc_module_name":9,"category_name":57,"show_sort_weight":24,"slug":58},19,"General","general",{"code":4,"msg":60,"data":61},"ok",{"site_id":62,"language":63,"slug":64,"title":65,"keywords":66,"description":67,"schema_data":68,"social_meta":123,"head_meta":125,"extra_data":127,"updated_unix":129},105,"en","a-formal-basis-for-safety-case-patterns","A Formal Basis for Safety Case Patterns","","This paper formalizes safety case patterns to enable reliable reuse of argument structures for reasoning about safety. Existing pattern practices use informal, descriptive non-executable specifications, limiting automated instantiation, composition, and manipulation while hindering standardization and tool interoperability. The work provides a formal definition, formal semantics for patterns, and a generic data model and instantiation algorithm. It demonstrates these contributions via the requirements breakdown pattern.",{"@graph":69,"@context":122},[70,84,105],{"@type":71,"itemListElement":72},"BreadcrumbList",[73,77,79,82],{"item":74,"name":75,"@type":76,"position":8},"https://docshare.wps.com","Home","ListItem",{"item":78,"name":9,"@type":76,"position":14},"https://docshare.wps.com/document/",{"item":80,"name":40,"@type":76,"position":81},"https://docshare.wps.com/document/research-report/",3,{"item":83,"name":65,"@type":76,"position":19},"https://docshare.wps.com/document/a-formal-basis-for-safety-case-patterns/272828/",{"url":83,"name":65,"@type":85,"image":86,"author":91,"headline":65,"publisher":94,"fileFormat":97,"inLanguage":63,"description":67,"dateModified":98,"datePublished":99,"encodingFormat":97,"isAccessibleForFree":100,"interactionStatistic":101},"DigitalDocument",{"url":87,"@type":88,"width":89,"height":90},"https://docshare.wps.com/thumbnails/a-formal-basis-for-safety-case-patterns/272828.png","ImageObject",300,407,{"name":92,"@type":93},"Dipper","Person",{"url":74,"name":95,"@type":96},"DocShare","Organization","application/pdf","2026-10-27","2026-09-15",true,{"@type":102,"interactionType":103,"userInteractionCount":52},"InteractionCounter",{"@type":104},"ViewAction",{"@type":106,"mainEntity":107},"FAQPage",[108,114,118],{"name":109,"@type":110,"acceptedAnswer":111},"What problem does the paper address about current safety case pattern practice?","Question",{"text":112,"@type":113},"Current practice relies on informal, non-executable specifications that mainly support replication and manual substitution, which is labor intensive, hard to scale, and limits standardization and tool interoperability.","Answer",{"name":115,"@type":110,"acceptedAnswer":116},"What are the main contributions of the paper?",{"text":117,"@type":113},"It provides (i) a formal definition for safety case patterns, (ii) formal semantics for patterns in terms of concrete instantiations, and (iii) a generic data model and algorithm for pattern instantiation.",{"name":119,"@type":110,"acceptedAnswer":120},"How does the paper illustrate its approach?",{"text":121,"@type":113},"By applying the formalism to a new pattern, the requirements breakdown pattern, building on the authors’ previous work.","https://schema.org",{"og:url":83,"og:type":124,"og:title":65,"og:site_name":95,"og:description":67},"article",{"robots":126,"canonical":83},"index,follow",{"doc_id":128,"site_id":62},272828,1789467780,{"code":4,"msg":5,"data":131},{"doc_id":128,"user_id":132,"nickname":92,"user_avatar":133,"doc_module":4,"category_id":39,"category_name":40,"doc_title":65,"doc_description":67,"doc_content":134,"file_id":135,"file_url":136,"file_type":137,"file_size":138,"view_count":52,"is_deleted":4,"is_public":8,"is_downloadable":8,"audit_status":8,"page_count":139,"language":140,"language_code":63,"site_id":62,"html_lang":63,"table_of_contents":141,"faqs":142,"seo_title":143,"seo_description":67,"update_tm":129,"read_time":41,"preview_page_count":4},1374404997633,"https://ap-avatar.wpscdn.com/davatar_a8503ba1806abce46bf441b54a3ca4cd","A Formal Basis for Safety Case Patterns  \nEwen Denney and Ganesh Pai  \nSGT / NASA Ames Research Center  \nMoffett Field, CA 94035, USA  \n{ewen .denney,[ganesh.pai](ganesh.pai}@nasa.gov)[}](ganesh.pai}@nasa.gov)[@nasa.gov](ganesh.pai}@nasa.gov)  \nAbstract. By capturing common structures of successful arguments, safety case patterns provide an approach for reusing strategies for reasoning about safety. In the current state of the practice, patterns exist as descriptive specifications withinformal semantics, which not only offer little opportunity for more sophisticated usage such as automated instantiation, composition and manipulation, but also impede standardization efforts and tool interoperability. To address these concerns, this paper gives (i) a formal definition for safety case patterns, clarifying both restrictions on the usage of multiplicity and well-founded recursion in structural abstraction, (ii) formal semantics to patterns, and (iii) a generic data model and algorithm for pattern instantiation. We illustrate our contributions by application to a new pattern, the requirements breakdown pattern, which builds upon our previous work.  \nKeywords: Safety cases, Safety case patterns, Formal methods, Automation.  \n1 Introduction  \nSafety case patterns are intended to capture repeatedly used structures of successful (i.e., correct, comprehensive and convincing) arguments, within a safety case [11] . In effect, they provide a re-usable approach to safety argumentation by serving as a means to capture expertise, so-called tricks of the trade, i.e., known best practices, successful certification approaches, and solutions that have evolved over time. The existing notion of a pattern 1 is an extended argument structure, often specified graphically using the Goal Structuring Notation (GSN) [8], which abstractly captures the reasoning linking certain (types of) claims to the available (types of) evidence, and is accompanied by a clear prescription and proscription of its usage.  \nIn current practice, patterns have informal semantics and, in general, they are given as descriptive non-executable specifications. Specifically, in existing tools, pattern-based reuse does not go beyond simple replication of a pattern argument structure, and manual replacement of its abstract elements with their concrete instances. Such usage isnot only effort intensive but also unlikely to scale well. Algorithmically instantiating patterns is a natural solution to address this deficiency. However, to our knowledge, existing tools provide little to no such functionality, in part, because of the lack of a formal basis. The latter additionally impedes standardization and tool interoperability.  \n1 In the rest of the paper we will simply use “pattern” instead of “safety case pattern”.  \nF. Bitsch, J. Guiochet, and M. Kaniche (Eds.): SAFECOMP 2013, LNCS 8153, pp. 21–32, 2013 .  \n􀀂c Springer-Verlag Berlin Heidelberg 2013  \n22 E. Denney and G. Pai  \nThis paper extends the state of the art in safety case research though the following contributions: we give a formalization for argument structures elaborating on the nuances and ambiguities that arise when using the available GSN abstractions [8] for pattern specification. In particular, we clarify restrictions on the usage of multiplicity and extend the basic concepts to include a notion of well-founded recursion. Next, we give a formal semantics to patterns in terms of their (set of) concrete instantiations. We specify a generic data model and pattern instantiation algorithm, and illustrate their application to a new pattern: the requirements breakdown pattern, which builds upon our previous work [3],[6] . Specifically, both generalize and replace their previous incarnations [3] that mainly operated on requirements and hazard tables.  \n2 Background  \nCurrently [10],[11], a pattern specification mainly contains:  \n– Name: the identifying label of the pattern giving the key principle of its argument.  \n– Intent: that which ","cbCaikQhrg3HIVe2","https://ap.wps.com/l/cbCaikQhrg3HIVe2","pdf",448601,12,"English","# Introduction\n## Background","[{\"question\":\"What problem does the paper address about current safety case pattern practice?\",\"answer\":\"Current practice relies on informal, non-executable specifications that mainly support replication and manual substitution, which is labor intensive, hard to scale, and limits standardization and tool interoperability.\"},{\"question\":\"What are the main contributions of the paper?\",\"answer\":\"It provides (i) a formal definition for safety case patterns, (ii) formal semantics for patterns in terms of concrete instantiations, and (iii) a generic data model and algorithm for pattern instantiation.\"},{\"question\":\"How does the paper illustrate its approach?\",\"answer\":\"By applying the formalism to a new pattern, the requirements breakdown pattern, building on the authors’ previous work.\"}]","A Formal Basis for Safety Case Patterns | PDF"]