1,496 research outputs found
KALwEN: A New Practical and Interoperable Key Management Scheme for Body Sensor Networks
Key management is the pillar of a security architecture. Body sensor networks(BSNs) pose several challenges -- some inherited from wireless sensor networks(WSNs), some unique to themselves -- that require a new key management scheme to be tailor-made. The challenge is taken on, and the result is KALwEN, a new lightweight scheme that combines the best-suited cryptographic techniques in a seamless framework. KALwEN is user-friendly in the sense that it requires no expert knowledge of a user, and instead only requires a user to follow a simple set of instructions when bootstrapping or extending a network. One of KALwEN's key features is that it allows sensor devices from different manufacturers, which expectedly do not have any pre-shared secret, to establish secure communications with each other. KALwEN is decentralized, such that it does not rely on the availability of a local processing unit (LPU). KALwEN supports global broadcast, local broadcast and neighbor-to-neighbor unicast, while preserving past key secrecry and future key secrecy. The fact that the cryptographic protocols of KALwEN have been formally verified also makes a convincing case
Nonmonotonic Trust Management for P2P Applications
Community decisions about access control in virtual communities are
non-monotonic in nature. This means that they cannot be expressed in current,
monotonic trust management languages such as the family of Role Based Trust
Management languages (RT). To solve this problem we propose RT-, which adds a
restricted form of negation to the standard RT language, thus admitting a
controlled form of non-monotonicity. The semantics of RT- is discussed and
presented in terms of the well-founded semantics for Logic Programs. Finally we
discuss how chain discovery can be accomplished for RT-.Comment: This paper appears in the proceedings of the 1st International
Workshop on Security and Trust Management (STM 2005). To appear in ENTC
Benchmarking Implementations of Functional Languages with ``Pseudoknot'', a Float-Intensive Benchmark
Over 25 implementations of different functional languages are benchmarked using the same program, a floatingpoint intensive application taken from molecular biology. The principal aspects studied are compile time and execution time for the various implementations that were benchmarked. An important consideration is how the program can be modified and tuned to obtain maximal performance on each language implementation.\ud
With few exceptions, the compilers take a significant amount of time to compile this program, though most compilers were faster than the then current GNU C compiler (GCC version 2.5.8). Compilers that generate C or Lisp are often slower than those that generate native code directly: the cost of compiling the intermediate form is normally a large fraction of the total compilation time.\ud
There is no clear distinction between the runtime performance of eager and lazy implementations when appropriate annotations are used: lazy implementations have clearly come of age when it comes to implementing largely strict applications, such as the Pseudoknot program. The speed of C can be approached by some implemtations, but to achieve this performance, special measures such as strictness annotations are required by non-strict implementations.\ud
The benchmark results have to be interpreted with care. Firstly, a benchmark based on a single program cannot cover a wide spectrum of 'typical' applications.j Secondly, the compilers vary in the kind and level of optimisations offered, so the effort required to obtain an optimal version of the program is similarly varied
Introduction
Within library and information science (LIS), the study of information behavior has traditionally focused on documentary sources of information and to some degree information that is shared through interaction.1 Such an emphasis reflects the origins of the whole field in the study of the information behavior of users of libraries and other institutions that provide access to encoded forms of knowledge. Yet the centrality of embodied experience in all aspects of human life makes the relative neglect of the body in information behavior studies surprising and potentially problematic, as a number of authors have suggested (Cox, Griffin, and Hartel 2017; Lueg 2014, 2015; Lloyd 2009, 2010, 2014; Olsson, 2010, 2016). This special double issue of Library Trends on “Information and the Body” brings together researchers interested in embodied information, including in how we receive information through the senses, what the body “knows,” and the way the body is a sign that can be interpreted by others
A programming and a modelling perspective on the evaluation of Java card implementations
Java Card Technology has provided a huge step forward in programming smart cards: from assembler to using a high level Object Oriented language. However, the authors have found some differences between the current Java Card version (2.1) and main stream Java that may restrict the benefits of using Java achievable in smartcard programming. In particular, efforts towards evaluating Java Card implementations at a high level of assurance may be hampered by the presence of these differences as well as by the complexity of the Java Card VM and API. The goal of the present paper is to detail the differences from a programming and a modelling point of view
Thinking Outside the Box Turtle: Public Perceptions of an Imperiled Species
Eastern box turtles (Terrapene carolina carolina) experience negative impacts from human activities. Collection for the pet trade or mortalities caused by lawn mowers and vehicles are detrimental to populations, which have experienced rapid decline in Indiana. Understanding perceptions and attitudes held about species can help outreach. This study aims to observe how perceptions and fear response differ between a) genders, b) contact with box turtles, and c) conservation group membership. Mail surveys were administered to 1,378 residents of the Blue River Watershed in Southern Indiana. Respondents rated box turtles on 11 semantic differential pairs and reported their agreement towards a series of Likert-scale questions that measured conservation and fear related attitudes. While fear response was relatively low across groups, women had had a significantly higher fear response (1.71 out of 5) than men (1.53). Women had higher agreement that box turtles are important to the Blue River ecosystem (4.08 vs. 3.77). Respondents who had encountered a box turtle associated box turtles with positive phrases and had higher agreement to ecosystem importance (3.94 vs. 3.39). Members of conservation groups had significantly higher agreement to ecosystem importance (4.25) and approval of government spending on box turtle conservation (3.31) compared to non-members (3.81 and 2.94). There was no correlation between level of fear response and recognition of ecosystem importance. Exposure to box turtles can be a mechanism of instilling positive perceptions of the species. Outreach may not need to address “fearful” perceptions of this species for individuals to still value box turtle conservation
Novel African trypanocidal agents: membrane rigidifying peptides
The bloodstream developmental forms of pathogenic African trypanosomes are uniquely susceptible to killing by small hydrophobic peptides. Trypanocidal activity is conferred by peptide hydrophobicity and charge distribution and results from increased rigidity of the plasma membrane. Structural analysis of lipid-associated peptide suggests a mechanism of phospholipid clamping in which an internal hydrophobic bulge anchors the peptide in the membrane and positively charged moieties at the termini coordinate phosphates of the polar lipid headgroups. This mechanism reveals a necessary phenotype in bloodstream form African trypanosomes, high membrane fluidity, and we suggest that targeting the plasma membrane lipid bilayer as a whole may be a novel strategy for the development of new pharmaceutical agents. Additionally, the peptides we have described may be valuable tools for probing the biosynthetic machinery responsible for the unique composition and characteristics of African trypanosome plasma membranes
The case for emotional intelligence in organizational research
Since its popularization by Goleman (1995), the concept of emotional intelligence has been the subject of ongoing controversy, so it is understandable that the model we proposed, which includes emotional intelligence as a moderator variable, would attract its share of criticism
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