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Global navigation satellite systems (GNSSs) provide accurate positioning and timing services in a large gamut of sectors, including financial institutions, Industry 4.0, and Internet of things (IoT). Any industrial system involving multiple devices interacting and/or coordinating their functionalities needs accurate, dependable, and trustworthy time synchronization, which can be obtained by using authenticated GNSS signals. However, GNSS vulnerabilities to time-spoofing attacks may cause security issues for their applications. Galileo is currently developing new services aimed at providing increased security and robustness against attacks, such as the open service navigation message authentication (OS-NMA) and commercial authentication service (CAS). In this paper, we propose a robust and secure timing protocol that is independent of external time sources, and solely relies on assisted commercial authentication service (ACAS) and OS-NMA features. We analyze the performance of the proposed timing protocol and discuss its security level in relation to malicious attacks. Lastly, experimental tests were conducted to validate the proposed protocol. [ABSTRACT FROM AUTHOR]

The use of Computer Algebra Systems (CAS) in years 9 and 10 classrooms as a tool to support learning or in preparation for senior secondary mathematics is controversial. This paper presents an analysis of the positive and negative aspects of using CAS identified in the literature related to these year levels, along with the perceptions of 12 experienced secondary teachers who were working with years 9 and 10 students. The literature review shows that CAS is valued for calculation and manipulation capabilities, the option of alternative representations, the opportunity for systematic exploration and for prompting rich discussion. However, the technical overhead, initial workload for the teacher and unresolved questions about the perceived relative contribution of machine and by-hand work to learning currently pose obstacles to teaching with CAS in the middle secondary years. The teachers who contributed data to this study perceived that using CAS in their teaching is, on balance, worth the effort. However, they believed that CAS is of most benefit to their high ability students and may present an obstacle to their low ability students’ learning of mathematics. [ABSTRACT FROM AUTHOR]

This paper presents a semiotic analysis of the (often claimed) potential of computer algebra systems (CAS) for enabling mathematical activity on a conceptual level higher than usual. Theoretical points are illustrated by examples from a development project in the context of a first year university course on calculus. We also discuss how they may be used in `a posteriori' didactical analysis and in didactical engineering. [ABSTRACT FROM AUTHOR]

Purpose - For decades, archivists have been appraising, preserving, and providing access to digital records by using archival theories and methods developed for paper records. However, production and consumption of digital records are informed by social and industrial trends and by computer and data methods that show little or no connection to archival methods. The purpose of this chapter is to reexamine the theories and methods that dominate records practices. The authors believe that this situation calls for a formal articulation of a new transdiscipline, which they call computational archival science (CAS). Design/Methodology/Approach - After making a case for CAS, the authors present motivating case studies: (1) evolutionary prototyping and computational linguistics; (2) graph analytics, digital humanities, and archival representation; (3) computational finding aids; (4) digital curation; (5) public engagement with (archival) content; (6) authenticity; (7) confluences between archival theory and computational methods: cyberinfrastructure and the records continuum; and (8) spatial and temporal analytics. Findings - Each case study includes suggestions for incorporating CAS into Master of Library Science (MLS) education in order to better address the needs of today's MLS graduates looking to employ "traditional" archival principles in conjunction with computational methods. A CAS agenda will require transdisciplinary iSchools and extensive hands-on experience working with cyberinfrastructure to implement archival functions. Originality/Value - We expect that archival practice will benefit from the development of new tools and techniques that support records and archives professionals in managing and preserving records at scale and that, conversely, computational science will benefit from the consideration and application of archival principles. [ABSTRACT FROM AUTHOR]

Different Engineering applications require dealing with improper integral on unbounded domains (improper integrals of the first kind). The classical way for solving these integrals is by means of elementary Calculus (antiderivatives and limit computations) or using numerical approaches. In both situations different problems can arise. For example: the non-existence of antiderivative, the corresponding limit does not exist or integrals depending on parameters which complicate the use of numerical approaches. In order to solve this situation, Advanced Calculus techniques, such as Laplace or Fourier Transforms and the Residue Theorem can be applied. A brief review of the corresponding theoretical frame is included in this paper. Computer Algebra Systems ( Cas ) are pieces of software that allow symbolic computations. Nowadays, there are many Cas in the market with an increasing level of sophistication which make them a very powerful tool in Engineering. In this paper, a brief review on the history of Cas evolution is introduced. In this work, some Advanced Calculus techniques for computing improper integrals of the first kind which cannot be solved with standard procedures are described. These techniques could be easily integrated in almost every Cas . However, we have detected some lacks of these techniques in many widely used Cas . In this paper, some tests involving improper integrals have been developed. These tests have been used to check the capabilities of some Cas and the results have provided a classification of the Cas with respect to this field. One of the main contributions in this work is the generation of different rules to compute improper integrals of the first kind. The rules have been classified in specific rules (those coming from the tests) and general rules (those coming from theoretical frames and generalizations of the specific rules). These rules are easy to include in a Cas increasing the facilities of the Cas in the field of improper integral computation. [ABSTRACT FROM AUTHOR]

In this paper our experience in application of CAS Maple for modelling and solving counting problems as well as for solving recurrence equations is represented. Some procedures for calculating combinations with repetition and variations with repetition in case of authorized number on appearance of elements are given. The result is a list of the allowed number of appearances of the element in the polynomial involved in the generating function. Some conclusions have been visualized. The represented approaches correspond to the Curriculum of the Bachelor Degree Program in Applied Mathematics and Informatics at TU-Sofia and are based on methodological principles and the educational tradition in our country. [ABSTRACT FROM AUTHOR]

The development of organizational information systems over a long period of time, often result in the creation and use of multiple independent information systems within the organization, which are on the other side mostly set in heterogeneous IT structure. By setting up these systems in this information structure, as one of the most important processes in the integration of systems in the foreground is outlined the process for authenticating users who have access to information. Given the complexity of this process in a heterogeneous information environment, within the paper we make a conceptual overview of key aspects for the design and application of the system for authentication. [ABSTRACT FROM AUTHOR]

This paper shows how a historically constructed long-distance hiking trail can have various and discordant meanings. It draws on archival and promotional material, interviews and ethnographic fieldwork and examines the original Cathar Trail agenda and hikers' contemporary practice of the trail in the South of France. This cultural heritage trail was created in the 1980s and based on historical narratives and heritage sites. Hikers, however, redefined the Cathar Trail through their motivations, trip organisation and style of travel. Their journeys generated a trail at odds with the initial Trail agenda which sought to encourage hikers to engage in time travel. In sum, then, the paper demonstrates that the meaning of a trail for the hikers is formed through their experience of journeying rather than a cultural heritage agenda. [ABSTRACT FROM AUTHOR]

Copyright of Borealis: An International Journal of Hispanic Linguistics is the property of Nordic Council for Reindeer Husbandry Research and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

IEEE Security & Privacy met with several interesting speakers at the 23rd ACM Conference on Computer and Communications Security (CCS), held 24-28 October 2016 in Vienna. IEEE S&P is highlighting these interviews in its Spotlight department. This issue features MIT Lincoln Laboratory's Hamed Okhravi, cryptographer and cryptanalyst Bart Preneel of KU Leuven, and former assistant director for US federal cybersecurity Gregory Shannon. They discuss issues ranging from moving-target defenses to Certificate Authorities to education and government regulation and strategies. [ABSTRACT FROM PUBLISHER]

The work presented in this paper deals with the accuracy of the sensitivity derivatives of aerodynamic cost functions obtained by using an adjoint method. The accuracy of these gradients is evaluated by comparison with gradients computed via finite-differences in a straight-forward manner. The advantages of the use of an adjoint method become extremely clear since the computational effort incurred in the calculation of a complete gradient with respect to an arbitrary number of variables is independent of the number of variables and the only cost involved is the calculation of one flow solution and one adjoint solution, where the adjoint equation is a linear equation and, hence, of reduced complexity. In order to focus on the design and optimization procedure, we limit our study to one of the simplest flows: a subsonic potential flow over an airfoil section. First, for a generic objective function, we present a tool to automatically compute the gradient expression through adjoint techniques based on MAPLE, one of the most powerful computer algebra system (CAS). Second, exploiting the linearity of the governing equation, an adjoint solver is implemented based on the classical Douglas-Neumann panel method. The use of the solver is illustrated for a sample design calculation. [ABSTRACT FROM AUTHOR]

• The distribution characteristics of CaS in the radial direction of the hearth were analyzed. • The formation mechanism and migration process of CaS in the hearth were analyzed. • The interface reaction between slag and coke is the main source of CaS formation in the furnace hearth. As the main occurrence form of sulfur element in blast furnace hearth, high content of CaS within the blast furnace hearth have a certain impact on low-carbon smelting of blast furnace. In this paper, the micro-morphology and distribution of CaS in the hearth area are studied by scanning electron microscopy and industrial CT, and the formation process of CaS in the deadman is clarified by drilling core samples of residual iron in the hearth of 3200 m3 blast furnace in China. The research results indicate that CaS in the hearth is mainly formed by slag-coke interface reaction and slag-iron interface reaction. Based on an analysis of the relative difficulty of these two pathways, it was observed that CaS is more readily generated through the slag-coke interface reaction. Based on the analysis of the difficulty of the two generation paths, it is found that CaS in the blast furnace hearth is more easily generated through slag coke interface reaction. The CaS particles generated in the hearth take the slag as the growth matrix, and with the flow of slag and iron and the renewal of the deadman coke, they are finally enriched and precipitated in the edge area of the deadman in the form of agglomerates. Based on the formation mechanism of CaS in the hearth, it is analyzed that the formation of CaS aggregates in the hearth is mainly affected by three factors: sulfur load, slag basicity and hearth temperature. This study provides a certain theoretical reference and guidance for steel enterprises aiming to reduce fuel consumption and achieve green production practices. [ABSTRACT FROM AUTHOR]

Organizations are increasingly looking to trusted data to drive their decision making process. Trusted data has a clear, defined and consistent quality which meets the expectations of the user. Data infrastructures which produce trusted data and provide organizations with the capability to make the right decisions at the right time are socio-technical networks, consisting of technical infrastructures and actor networks, and as such they are often complex and adaptive. Critical issues, challenges, and dilemmas can be identified while looking at data infrastructures as a socio-technical systems. This paper explores conditions and factors for effective and sustainable development of data infrastructures in organizations and suggests that the inherent complexity of data infrastructures requires a multi-faceted way of data governance. Several predefined components of data infrastructures which contain the behavior of agents through various coordination mechanisms have been developed to model the effect of data governance on data infrastructures. These components can be further customized to model an empirical situation more closely. Finally, the paper suggests institutionalization of data governance within an organization as a unifying concept towards the effectiveness and sustainability of data infrastructures, recognizing their inherent complexities. The approach is illustrated with a case study in the asset management domain. [ABSTRACT FROM AUTHOR]

Copyright of Studies in Contrastive Grammar / Studii de Gramatica Contrastiva is the property of Universitatea din Pitesti and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Prilozi za Istrazivanje Hrvatske Filozofske Bastine is the property of Institut za Filosofiju and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This article addresses the sustainability of using digital technologies in mathematics education. The paper emphasizes the need to understand how we can improve mathematics learning processes and the role of technology in these processes. Technology encompasses various fields such as science, manufacturing, services, and transportation, covering a wide range from machines to methods. The use of technology in mathematics education should also be evaluated within this scope. The article examines how digital technologies are used in mathematics classes and how this usage affects students’ mathematics learning processes. Technological advancements, ranging from graphic calculators to web-based applications, have transformed mathematics instruction. However, it is an important question whether technology is used only to access answers more quickly or to improve how mathematics is learned. Especially when there are numerous equations and programming languages in mathematics classes, the limitations of material presentation must be considered. Additionally, this research highlights the importance of using platforms for implementing online learning policies.

This paper aims to display the most significant feature of Proust's thinking of time consisting in a specific connection between the time as a concrete lived quality and the extra-temporal qualitative difference or essence. The time in its most concrete realizations, as Proust makes it clear, is always a particular kind of „emanation” of the extra-temporal reality, which is likewise the final goal of the quest of the hero and the source of the creative process manifested in the novel. This nontemporal essence itself however remains hidden up to the very end of the novel. [ABSTRACT FROM AUTHOR]

In the 21st century, innovations have become an unquestioned sine qua non of everyday life. Our living conditions change rapidly, often without predictability, security, or critical reflexion. These changes easily turn into a form of political and social control of innovation-induced ruptures, keeping people on constant alert and making them abandon recently acquired practices for new ones. It can be argued that they represent a form of psychological coercion. Moreover, the growing pace of life-as-innovation, together with misguided assumptions and conclusions about life itself in the diversity of its local variations, produces new forms of inequality and misery among many societies around the globe. In the present paper, I explore how time, innovation, and values relate to each other in both academic life and life in general. I argue for prioritising well-informed reflexive works in the social sciences and the humanities against the pressures of time and frequently unfounded innovations. [ABSTRACT FROM AUTHOR]

Climatic changes significantly impact forest ecosystems, inevitably affecting forestry and forest-related industry. Considering that most forests are actively managed, there is a need to define the future risks and set a strategy for forestry and silviculture in a changing world. This review provides insight into the new challenges and opportunities forest management and silviculture face in the coming decades. There is sound recognition of risk factors expected from climate change, yet great uncertainty exists in the predictions of the response of forests to new conditions. Additionally, the stakeholders' interests in the goods and services offered by forests are changing, and this also needs to be taken into account in future forest management. Undoubtedly, the goal of future forestry and silviculture in the 21st century will be primarily to ensure the continuity and sustainability of the forest. Sustainable use of goods and ecosystem services from forests will be directly related to the continuity and sustainability of the forest in the future. Adaptive forest management aims to promote the adaptive capacity of forests to new conditions resulting from climate change. If adaptation efforts are effective, adaptive forest management should be a kind of risk management. There is no one-fits-all strategy for adaptation to uncertain future conditions. Silviculture in the 21st century is expected to be more conducive to adapting forests to changes. Operational silvicultural activities should focus on ensuring the resilience and adaptation of forests to future environmental conditions. Modern silviculture offers activities that fall within the scope of contemporary close-to-nature silviculture practices. However, some of the currently applied practices will require review and modification to be applicable under new conditions. This review also identifies the need to fill knowledge gaps in order to develop more effective and flexible adaptation strategies to foster sustainable forest development and, thus, sustainable forestry. [ABSTRACT FROM AUTHOR]

Sports managers and coaches are the core element of an environment focused on the win or lose ideology, characterised as it is by insecurity and volatility. They are one of the central figures in the world of sport, but there is not enough attention in relation to their status, their role and responsibility. Similarly, the relationship that binds them to their club has to be object of legal studies, in light of the peculiarities of the industry and of their function. This paper aims at providing an analysis of the theme of Coach and Manager Contracts, to highlights which are the main features of the relationship that exists between the coach and his club, and understand what might differentiate this from other type of relationship in the world of sport. The most important element to be addressed in this context is related to the termination of the contract of employment between the manager and the team. In considering the duties and responsibilities of the parties, as expressed in the contract or regulated in other forms, the paper will give account of the trends developed in this context and the main reasons for concern. The study will look at the regulations and the practices that are in place in several European and International Legal System, as well as the relevant case law which has been drawn from national Courts and Arbitration Tribunals, and International Tribunals such as the CAS. The objective is to offer an analysis of the topic in the context of a broad international framework, that will possibly highlight common tendencies, reasons for concern and future developments in this area. [ABSTRACT FROM AUTHOR]

Some challenges to increasing actuarial science program size through recruiting broadly among potential students are identified. Possible solutions depend on the structures and culture of the school. Up to three student cohorts may result from partition of potential students by the levels of academic progress before program entry: students entering college for the first time, undergraduate transfers, and baccalaureate degree holders. Serving full-time students from these diverse academic levels—and also part-time students who may be from any of the cohorts—involves adaptations such as added recruiting methods, modified curriculum sequencing, extra one-on-one advising, and adjusted professional development activities. As a starting point for faculty dialogue, this paper presents some data and gives references and discussion points. [ABSTRACT FROM PUBLISHER]

This paper addresses approaches to handle System Engineering and Integration (SE&I) activities associated with complex adaptive systems (CAS). In this paper we will talk about two major initiatives within advanced SEI capabilities that address risk driven engineering and integration challenges posed from a CAS like environment. The first initiative is based on the use of an advanced Conops development and modelling approach implemented through a CONOPS Simulator concept. Next initiative outlines advanced applications of Reference Architectures (RA's) as it relates to system design activities within a CAS environment. These initiatives are applied as the foundation for a risk adverse design within CAS Enterprises. [ABSTRACT FROM AUTHOR]

Copyright of Avaliação Psicológica is the property of Instituto Brasileiro de Avaliacao Psicologica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Filozofski Vestnik is the property of Scientific Research Centre of Slovenian Academy of Sciences & Arts and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Systems engineers have always been concerned with the problems surrounding complex systems. An evolutionary class of complex systems called Complex Adaptive Systems (CAS) is even more relevant today as we struggle to understand and cope with the often undesirable emergence effects of some of these systems, evidenced by recurring financial and sociopolitical crises. A key characteristic of CAS is a large, diverse, and sometimes unknown set of interactions both internally and across the system boundary. For the purpose of managing this complexity we present in this paper the concept that a principles orientation as compared to rules orientation of a complex system is an important and useful characteristic in need of further study. The US financial system is used as a CAS exemplar in support of this inquiry. ©2012 Wiley Periodicals, Inc. Syst Eng 15 [ABSTRACT FROM AUTHOR]

Copyright of ESSACHESS is the property of ESSACHESS and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Universitatis Palackianae Olomucensis. Gymnica is the property of Palacky University in Olomouc and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Filozofski Vestnik is the property of Scientific Research Centre of Slovenian Academy of Sciences & Arts and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Accuracy in navigated surgery depends on placement and registration of stable reference markers close to the anatomic region of interest. Navigation in small and complex anatomic regions, such as the scaphoid, is challenging due to difficulties in placing a stable reference marker. In the current paper, we describe the use of a customized wrist-positioning device “Scaph-splint” with a built-in reference marker that facilitates navigated scaphoid screw insertion in combination with a 3D imaging device. Initial cadaveric feasibility study Five fresh-frozen cadaveric upper extremity specimens were utilized. Each specimen was secured onto the “Scaph-splint” with the wrist in about 90° of extension. Using a 3D fluoroscope, a series of images were taken of the carpal bones and reconstructed in axial, sagittal, and coronal planes. Navigated planning and guidance of scaphoid drilling and screw placement was performed. Next, a repeat 3D scan was taken to analyze the drill canal. The accuracy of navigated scaphoid drilling, drilling trials, and any penetration of the scaphoid outside of the planned drill trajectory were evaluated. A grading scheme was used to assess the drilling accuracy: Grade 1 <1 mm deviation, Grade 2 <2 mm deviation, Grade 3 <3 mm. Scaphoid drilling was confirmed to be completely accurate (Grade 1) in two specimens, highly accurate (Grade 2) in two specimens, and accurate (Grade 3) in one specimen. No specimen required a repeat drilling of the scaphoid. In one specimen, the proximal scaphoid pole was perforated by the drill. No registration failures or loosening of the reference marker occurred. The use of the “Scaph-splint” enabled stabilization of the hand and wrist, thus adequately fixing the reference marker in relation to scaphoid for optimal navigation and screw placement without the need to directly penetrate the scaphoid with a reference marker. The use of 3D fluoroscopy further increased the accuracy and precision of scaphoid screw placement. [ABSTRACT FROM AUTHOR]

In this paper, attitudes toward the computer of three different samples created according to educational levels were studied. In the paper, scales belonging to Nickell and Pinto were used as Computer Attitude Scale. Internal consistency, stability and validity of the CAS measurement instrument were also tested and discussed. The findings indicate that the CAS demonstrates acceptable construct validity, reliability and stability over time, as well as an ability to predict computer usage. It was decided to divide the CAS items into three subscales in terms of their content, and attitudes were compared in terms of different samples. University graduates like scholars, teachers, and civil servants who constituted sample I, were found to have the lowest positive attitude towards the computer, as well as the lowest negative attitude. It was found out that the people with the highest positive attitude were secondary and higher school students who constituted sample III. [ABSTRACT FROM AUTHOR]