Log. Methods Comput. Sci.最新文献_第7页

Conformance Relations and Hyperproperties for Doping Detection in Time and Space 时间和空间掺杂检测的一致性关系和超性质

Log. Methods Comput. Sci. Pub Date : 2020-12-07 DOI: 10.46298/lmcs-18(1:14)2022

Sebastian Biewer, Rayna Dimitrova, M. Fries, Maciej Gazda, Thomas S. Heinze, H. Hermanns, M. Mousavi

引用次数: 3

Coalgebraic Semantics for Probabilistic Logic Programming 概率逻辑规划的共代数语义

Log. Methods Comput. Sci. Pub Date : 2020-12-07 DOI: 10.23638/LMCS-17(2:2)2021

Tao Gu, F. Zanasi

引用次数: 2

Pushdown Automata and Context-Free Grammars in Bisimulation Semantics 双模拟语义中的下推自动机和上下文无关语法

Log. Methods Comput. Sci. Pub Date : 2020-12-07 DOI: 10.46298/lmcs-19(1:15)2023

J. Baeten, C. Carissimo, B. Luttik

引用次数: 1

Specification and Verification of Timing Properties in Interoperable Medical Systems 互操作医疗系统中时序特性的规范与验证

Log. Methods Comput. Sci. Pub Date : 2020-12-07 DOI: 10.46298/lmcs-18(2:13)2022

Mahsa Zarneshan, F. Ghassemi, E. Khamespanah, M. Sirjani, J. Hatcliff

{"title":"Specification and Verification of Timing Properties in Interoperable Medical Systems","authors":"Mahsa Zarneshan, F. Ghassemi, E. Khamespanah, M. Sirjani, J. Hatcliff","doi":"10.46298/lmcs-18(2:13)2022","DOIUrl":"https://doi.org/10.46298/lmcs-18(2:13)2022","url":null,"abstract":"To support the dynamic composition of various devices/apps into a medical system at point-of-care, a set of communication patterns to describe the communication needs of devices has been proposed. To address timing requirements, each pattern breaks common timing properties into finer ones that can be enforced locally by the components. Common timing requirements for the underlying communication substrate are derived from these local properties. The local properties of devices are assured by the vendors at the development time. Although organizations procure devices that are compatible in terms of their local properties and middleware, they may not operate as desired. The latency of the organization network interacts with the local properties of devices. To validate the interaction among the timing properties of components and the network, we formally specify such systems in Timed Rebeca. We use model checking to verify the derived timing requirements of the communication substrate in terms of the network and device models. We provide a set of templates as a guideline to specify medical systems in terms of the formal model of patterns. A composite medical system using several devices is subject to state-space explosion. We extend the reduction technique of Timed Rebeca based on the static properties of patterns. We prove that our reduction is sound and show the applicability of our approach in reducing the state space by modeling two clinical scenarios made of several instances of patterns.","PeriodicalId":314387,"journal":{"name":"Log. Methods Comput. Sci.","volume":"31 9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-12-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125705612","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}

引用次数: 0

Survey on Parameterized Verification with Threshold Automata and the Byzantine Model Checker 阈值自动机和拜占庭模型检查器的参数化验证研究

Log. Methods Comput. Sci. Pub Date : 2020-11-30 DOI: 10.46298/lmcs-19(1:5)2023

I. Konnov, Marijana Lazi'c, Ilina Stoilkovska, Josef Widder

{"title":"Survey on Parameterized Verification with Threshold Automata and the Byzantine Model Checker","authors":"I. Konnov, Marijana Lazi'c, Ilina Stoilkovska, Josef Widder","doi":"10.46298/lmcs-19(1:5)2023","DOIUrl":"https://doi.org/10.46298/lmcs-19(1:5)2023","url":null,"abstract":"Threshold guards are a basic primitive of many fault-tolerant algorithms that\u0000solve classical problems in distributed computing, such as reliable broadcast,\u0000two-phase commit, and consensus. Moreover, threshold guards can be found in\u0000recent blockchain algorithms such as, e.g., Tendermint consensus. In this\u0000article, we give an overview of techniques for automated verification of\u0000threshold-guarded fault-tolerant distributed algorithms, implemented in the\u0000Byzantine Model Checker (ByMC). These threshold-guarded algorithms have the\u0000following features: (1) up to $t$ of processes may crash or behave Byzantine;\u0000(2) the correct processes count messages and make progress when they receive\u0000sufficiently many messages, e.g., at least $t+1$; (3) the number $n$ of\u0000processes in the system is a parameter, as well as the number $t$ of faults;\u0000and (4) the parameters are restricted by a resilience condition, e.g., $n >\u00003t$. Traditionally, these algorithms were implemented in distributed systems\u0000with up to ten participating processes. Nowadays, they are implemented in\u0000distributed systems that involve hundreds or thousands of processes. To make\u0000sure that these algorithms are still correct for that scale, it is imperative\u0000to verify them for all possible values of the parameters.","PeriodicalId":314387,"journal":{"name":"Log. Methods Comput. Sci.","volume":"64 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122897176","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}

引用次数: 1

A new operational representation of dependencies in Event Structures 事件结构中依赖性的新操作表示

Log. Methods Comput. Sci. Pub Date : 2020-11-30 DOI: 10.46298/lmcs-17(4:16)2021

G. Pinna

引用次数: 0

Verifying liquidity of recursive Bitcoin contracts 验证递归比特币合约的流动性

Log. Methods Comput. Sci. Pub Date : 2020-11-28 DOI: 10.46298/lmcs-18(1:22)2022

Massimo Bartoletti, Stefano Lande, Maurizio Murgia, R. Zunino

{"title":"Verifying liquidity of recursive Bitcoin contracts","authors":"Massimo Bartoletti, Stefano Lande, Maurizio Murgia, R. Zunino","doi":"10.46298/lmcs-18(1:22)2022","DOIUrl":"https://doi.org/10.46298/lmcs-18(1:22)2022","url":null,"abstract":"Smart contracts - computer protocols that regulate the exchange of\u0000crypto-assets in trustless environments - have become popular with the spread\u0000of blockchain technologies. A landmark security property of smart contracts is\u0000liquidity: in a non-liquid contract, it may happen that some assets remain\u0000frozen, i.e. not redeemable by anyone. The relevance of this issue is witnessed\u0000by recent liquidity attacks to Ethereum, which have frozen hundreds of USD\u0000millions. We address the problem of verifying liquidity on BitML, a DSL for\u0000smart contracts with a secure compiler to Bitcoin, featuring primitives for\u0000currency transfers, contract renegotiation and consensual recursion. Our main\u0000result is a verification technique for liquidity. We first transform the\u0000infinite-state semantics of BitML into a finite-state one, which focusses on\u0000the behaviour of a chosen set of contracts, abstracting from the moves of the\u0000context. With respect to the chosen contracts, this abstraction is sound, i.e.\u0000if the abstracted contract is liquid, then also the concrete one is such. We\u0000then verify liquidity by model-checking the finite-state abstraction. We\u0000implement a toolchain that automatically verifies liquidity of BitML contracts\u0000and compiles them to Bitcoin, and we assess it through a benchmark of\u0000representative contracts.","PeriodicalId":314387,"journal":{"name":"Log. Methods Comput. Sci.","volume":"101 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116324048","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}

引用次数: 3

A theory of transaction parallelism in blockchains 区块链中的事务并行理论

Log. Methods Comput. Sci. Pub Date : 2020-11-27 DOI: 10.46298/lmcs-17(4:10)2021

Massimo Bartoletti, Letterio Galletta, Maurizio Murgia

{"title":"A theory of transaction parallelism in blockchains","authors":"Massimo Bartoletti, Letterio Galletta, Maurizio Murgia","doi":"10.46298/lmcs-17(4:10)2021","DOIUrl":"https://doi.org/10.46298/lmcs-17(4:10)2021","url":null,"abstract":"Decentralized blockchain platforms have enabled the secure exchange of\u0000crypto-assets without the intermediation of trusted authorities. To this\u0000purpose, these platforms rely on a peer-to-peer network of byzantine nodes,\u0000which collaboratively maintain an append-only ledger of transactions, called\u0000blockchain. Transactions represent the actions required by users, e.g. the\u0000transfer of some units of crypto-currency to another user, or the execution of\u0000a smart contract which distributes crypto-assets according to its internal\u0000logic. Part of the nodes of the peer-to-peer network compete to append\u0000transactions to the blockchain. To do so, they group the transactions sent by\u0000users into blocks, and update their view of the blockchain state by executing\u0000these transactions in the chosen order. Once a block of transactions is\u0000appended to the blockchain, the other nodes validate it, re-executing the\u0000transactions in the same order. The serial execution of transactions does not\u0000take advantage of the multi-core architecture of modern processors, so\u0000contributing to limit the throughput. In this paper we develop a theory of\u0000transaction parallelism for blockchains, which is based on static analysis of\u0000transactions and smart contracts. We illustrate how blockchain nodes can use\u0000our theory to parallelize the execution of transactions. Initial experiments on\u0000Ethereum show that our technique can improve the performance of nodes.","PeriodicalId":314387,"journal":{"name":"Log. Methods Comput. Sci.","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126735310","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}

引用次数: 3

Strongly Normalizing Higher-Order Relational Queries 强规范化高阶关系查询

Log. Methods Comput. Sci. Pub Date : 2020-11-26 DOI: 10.46298/lmcs-18(3:23)2022

W. Ricciotti, J. Cheney

引用次数: 7

Characterization and Derivation of Heard-Of Predicates for Asynchronous Message-Passing Models 异步消息传递模型中听说谓词的表征和派生

Log. Methods Comput. Sci. Pub Date : 2020-11-25 DOI: 10.46298/lmcs-17(3:26)2021

A. Shimi, A. Hurault, P. Quéinnec

{"title":"Characterization and Derivation of Heard-Of Predicates for Asynchronous Message-Passing Models","authors":"A. Shimi, A. Hurault, P. Quéinnec","doi":"10.46298/lmcs-17(3:26)2021","DOIUrl":"https://doi.org/10.46298/lmcs-17(3:26)2021","url":null,"abstract":"In distributed computing, multiple processes interact to solve a problem\u0000together. The main model of interaction is the message-passing model, where\u0000processes communicate by exchanging messages. Nevertheless, there are several\u0000models varying along important dimensions: degree of synchrony, kinds of\u0000faults, number of faults... This variety is compounded by the lack of a general\u0000formalism in which to abstract these models. One way to bring order is to\u0000constrain these models to communicate in rounds. This is the setting of the\u0000Heard-Of model, which captures many models through predicates on the messages\u0000sent in a round and received on time. Yet, it is not easy to define the\u0000predicate that captures a given operational model. The question is even harder\u0000for the asynchronous case, as unbounded message delay means the implementation\u0000of rounds must depend on details of the model. This paper shows that\u0000characterising asynchronous models by heard-of predicates is indeed meaningful.\u0000This characterization relies on delivered predicates, an intermediate\u0000abstraction between the informal operational model and the heard-of predicates.\u0000Our approach splits the problem into two steps: first extract the delivered\u0000model capturing the informal model, and then characterize the heard-of\u0000predicates that are generated by this delivered model. For the first part, we\u0000provide examples of delivered predicates, and an approach to derive more. It\u0000uses the intuition that complex models are a composition of simpler models. We\u0000define operations like union, succession or repetition that make it easier to\u0000derive complex delivered predicates from simple ones while retaining\u0000expressivity. For the second part, we formalize and study strategies for when\u0000to change rounds. Intuitively, the characterizing predicate of a model is the\u0000one generated by a strategy that waits for as much messages as possible,\u0000without blocking forever.","PeriodicalId":314387,"journal":{"name":"Log. Methods Comput. Sci.","volume":"61 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127036199","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}

引用次数: 0