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关键词： Authentication   Cryptography   Protocols   Entropy   Resource management   Standards   Authentication   cryptographic protocols   communication system security  

摘要： Most of the existing works on securing the CAN bus are using the limited data-field of CAN frames to embed a cryptographic payload. Only very few works have suggested the use of the identifier field since identifiers are critical for the arbitration procedure and changing them at random would interfere with message priorities. To preserve priority on the bus, in this work we use an ordered CMAC buffer. In this way, we can authenticate the identifiers of CAN frames and check that the sender is a legitimate node while arbitration on the bus remains unaltered. Moreover, we determine that for real-world scenarios the achieved security level is very close to the length of the ID field despite the constraints from ordering. This procedure easily circumvents replay attacks and fuzz testing on the bus, which were exploited by many recent works. We prove the feasibility of our approach by testing practical implementations on automotive-grade microcontrollers and CAN-bus traffic allocations from a high-end vehicle. The computational requirements are some of the lowest achievable for securing CAN, with a dozen CMAC-AES computations being sufficient for extracting a table of one hundred identifiers.

关键词： 条形码   数字信息   数字对象唯一标识符   网址   互联网信息   DOI   唯一标识   信息标注  

摘要： 数字对象唯一标识符(digital object identifier,DOI)是对包括互联网信息在内的数字信息进行标识的一种工具。在传统的出版物中,书刊、磁带、光盘都有国际标准编号(ISBN、ISSN、ISCN)及其条形码,作为出版物的唯一标识。这些标识使出版物得到有效的管理,便于读者查找和利用。而网上的文档一旦变更了网址便无从追索。数字信息标注DOI如同出版物的条形码,是一个永久和唯一的标识号。

关键词： 数字对象唯一标识符   中华医学会系列杂志   DOI   条形码   数字信息   互联网信息   唯一标识   ISSN  

摘要： 数字对象唯一标识符(digital objeet identifier,DOI)是对包括互联网信息在内的数字信息进行标识的一种工具。在传统的出版物中,书刊、磁带、光盘都有国际标准编号(ISBN、ISSN、ISCN)及其条形码,作为出版物的唯一标识。这些标识使出版物得到有效的管理,便于读者查找和利用。而网上的文档一旦变更了网址便无从追索。数字信息标注DOI如同出版物的条形码,是一个永久和唯一的标识号。

关键词： 数字对象   标注规则   杂志内容   网络链接   网络传播权   知识产权   资源数字化   标识符  

摘要： 根据中华医学会杂志社有关通知要求,为更好的提升杂志内容资源数字化传播效能,保护数字资源在网络链接中的知识产权和网络传播权,实现对数字对象的持续追踪和阅读数据的有效统计,自2020年(第38卷)3期,我刊D0I号标注规则进行修订。

关键词： 1RM   screening   football   softball   volleyball  

摘要： Case, MJ, Knudson, DV, and Downey, DL. Barbell squat relative strength as an identifier for lower extremity injury in collegiate athletes. J Strength Cond Res 34(5): 1249-1253, 2020-The aim of the study was to determine the efficacy of using the relative strength level of Division I athletes in One repetition maximum (1RM) barbell back squat as an identifier of seasonal lower extremity (LE) injury. One repetition maximum back squat (kg) and reported LE injuries were retrospectively collected for Division I male football (n = 46), female volleyball and softball athletes (n = 25). Maximum preseason relative (body mass normalized) back squat strength values were compared with 2 analyses of variance (p < 0.05) between injured and uninjured male (football) and female athletes (softball & volleyball). Relative back squat strength was significantly lower in injured athletes than uninjured athletes in both men (F = 6.03, p = 0.02) and women (F = 4.68, p = 0.04) with a moderate to large effect size (g = 0.86-0.85). These data indicate the potential of 1RM back squat relative strength serving as one tool in multi-factor preseason screening for LE injury risk in these sports. Male athletes with relative squat strength below 2.2 and female athletes below 1.6 in these sports could be more susceptible to LE injury over a season. Strength professionals should consider using body mass normalized 1RM back squats as a screening tool for seasonal LE injury risk in college athletes.

关键词： Safety   Authorization   Computational modeling   Analytical models   Task analysis   Security   access control   usage control   authorization   and safety analysis  

摘要： Safety analysis is a fundamental problem in authorization models. Safety decidable models provide theoretical foundations for decentralized security administration. Attributes of objects are central to usage control authorization models. It has previously been shown that inclusion of a single infinite attribute leads to undecidable safety, even without any creation of objects. Therefore unrestricted inclusion of infinite attributes is not possible in a safety decidable model. On the other hand, it has recently been shown that the safety problem for the pre-authorization usage control sub-model with finite attribute domains, called PreUCON(A)(finite), is decidable even with unbounded object creation. A major limitation of finite attributes is the inability to link objects through attribute values in presence of unbounded object creation (since attributes that reference other objects must be infinite in this case). It would be desirable to have safety-decidable attribute-based models which include both finite and infinite attributes (necessarily with some restrictions). This paper develops a pre-authorization usage control sub-model, called PreUCON(A)(id), with attribute domains solely comprised of infinite object identifiers with considerable restrictions on how these attributes can be updated. Safety decidability for PreUCON(A)(id) is proved by defining the notion of omega-equivalent usage configurations, and showing that the reachable set of omega-equivalent usage configurations is computable and can be used to answer safety questions. The utility of such models in practice is illustrated by means of an example. The paper further shows that addition of even a single finite domain attribute to PreUCON(A)(id) results in undecidable safety. These results indicate that combining finite and infinite attributes in a safety decidable model is a challenging task, which will likely require carefully crafted restrictions on updates to these attributes. The formulation of suc

摘要： The study of words as a mathematical object is a deep and rich field of study. Algebra, Combinatorics, Theoretical Computer Science etc., are major disciplines, which are fully using this study. Combinatorial properties (via Codes, Free Hulls, Infinite Words), and algebraic properties of words are presented in this Thesis. The free semigroup on a set (alphabet) X and finite presentation of semigroups have a central place in the algebraic study of words. The last part of the Thesis is devoted to the study of identities in the alphabet X = {x, y} for a class of monoids. The characterization of such identities are given gradually; some elementary identities are established at the beginning. Using the canonical form of a word, mainly triples of positive integers are those that determine all these identities.

摘要： Unfortunately, the original version of the article [1] contained an error. A typo in the main equation (Eq. 1) has been introduced during the production process. The operator " = " in Eq. 1 "log(θ) =  α + u…" was missing.

关键词： Substance use disorder   recovery   self-identification   stigma   bias  

摘要： Recent studies associate identifiers, such as "alcoholic/addict", with stigma, discrimination, and service deficits. Yet, little is known about why and how self-identifiers are chosen. This study analyzed qualitative responses from individuals (N = 42) in recovery from substance use disorders (SUDs) concerning their use of "alcoholic/addict" or "person with a SUD". Evaluative structure and generative theories were developed via latent content analysis and grounded theory. Secondary analysis evidenced four thematic constructs: contextual significance, flexibility/rigidity, leveraging identity to counteract stigma, and indications of identity integration/disintegration. Some individuals indicated the contextual utility of certain identifiers, regardless of associated stigma and bias.

关键词： 国际标准关联标识符   知识资源   知识元   关联标识  

摘要： 国际标准关联标识符(ISLI)标准已经在新闻出版领域取得快速普及与应用。作为信息资源与用户的枢纽中心,图书馆领域与新闻出版业存在天然的联系,了解ISLI标准在新闻出版等领域的实施情况,有利于加速ISLI标准在图书馆行业的应用。文章在梳理ISLI标准的概念、编码体系、实践应用等的基础上,提出优化图书馆数字资源管理系统以支持ISLI编码的识别与管理,积极制定适合于图书馆知识资源和知识元关联的行业标准ISLI/LIB,进行基于ISLI/LIB的知识资源回溯关联、知识元关联服务以及注册中心的构建等应用对策,为用户提供更加精、准、深、专的知识资源和知识服务。