Secure synthesis and activation of protocol translation agents

Protocol heterogeneity is pervasive and is a major obstacle to effective integration of services in large systems. However, standardization is not a complete answer. Standardized protocols must be general to prevent a proliferation of standards, and can therefore become complex and inefficient. Specialized protocols can be simple and efficient, since they can ignore situations that are precluded by application characteristics. One solution is to maintain agents for translating between protocols. However, n protocol types would require agents, since an agent must exist for a source - destination pair. A better solution is to create agents as needed. This paper examines the issues in the creation and management of protocol translation agents. We focus on the design of Nestor, an environment for synthesizing and managing RPC protocol translation agents. We provide rationale for the translation mechanism and the synthesis environment, with specific emphasis on the security issues arising in Nestor. Nestor has been implemented and manages heterogeneous RPC agents generated using the Cicero protocol construction language and the URPC toolkit.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/49229/2/ds7402.pd

Pharmacology of MDMA- and Amphetamine-Like New Psychoactive Substances

New psychoactive substances (NPS) with amphetamine-, aminoindan-, and benzofuran basic chemical structures have recently emerged for recreational drug use. Detailed information about their psychotropic effects and health risks is often limited. At the same time, it emerged that the pharmacological profiles of these NPS resemble those of amphetamine or 3,4-methylenedioxymethamphetamine (MDMA). Amphetamine-like NPS induce psychostimulation and euphoria mediated predominantly by norepinephrine (NE) and dopamine (DA) transporter (NET and DAT) inhibition and transporter-mediated release of NE and DA, thus showing a more catecholamine-selective profile. MDMA-like NPS frequently induce well-being, empathy, and prosocial effects and have only moderate psychostimulant properties. These MDMA-like substances primarily act by inhibiting the serotonin (5-HT) transporter (SERT) and NET, also inducing 5-HT and NE release. Monoamine receptor interactions vary considerably among amphetamine- and MDMA-like NPS. Clinically, amphetamine- and MDMA-like NPS can induce sympathomimetic toxicity. The aim of this chapter is to review the state of knowledge regarding these substances with a focus on the description of the in vitro pharmacology of selected amphetamine- and MDMA-like NPS. In addition, it is aimed to provide links between pharmacological profiles and in vivo effects and toxicity, which leads to the conclusion that abuse liability for amphetamine-like NPS may be higher than for MDMA-like NPS, but that the risk for developing the life-threatening serotonin syndrome may be increased for MDMA-like NPS

A normalized LMS algorithm : Mean and second moment weight behavior

L'ALGORITHME LMS a filtre adaptif exige une connaissance a priori du niveau de pouvoir d'entrée pour choisir le gain d'algorithme, paramètre μ, pour la stabilité'et la focalisation. Puisque le niveau de pouvoir d'entrée' est habitvellement une des invonnves_statistiques, if est normalement evalve d'après les données antérievros ou de'but du processus d'adaptation. Il est ensuite supposé que l'évaluation est parfsite dans toute analyses ulte Rieure du comportement de 1' algorithme LMS. Dans cet' article, les effets de l'estimation du niveou de pouvoir sont incorporés dans des données dépendantes u qui apparaissent explicitment dans l'algorithme. On estime le comportement moyen et variable de l'algorithme normalisé en prenant en compte la dépendante statistique explicite de μ sur les données d'entrée. Le comportement moyen de l'algorithme est prouvé converger vers le poids wiener. Les effets de fluctuation des poids de l'algorithme sont également étudiés. Une équation a_constant coefficient matriciel est dérivée' d'après les fluctuations de poids du poids wiener. L'équation est résolve poiur une matrice de covariance_ o données blanches et poru l'ALE ovec une fréquence unique dons un état stable pour p. Des expressions pouir l'erreur de movais ojustement sont oussi' présentées. Il est prouvé que dans le cas de le matrice de covariance o données blonches la mise en moyenné d'un e chantillon d'a peu prés dux données produit des degredations negligeobles comparé e 1' algorithme LMS Dons l'application de l'ALE, les fluctuations de poids de l'etot-stable sont prouvées ehe dépendantes modalement, étant plus grondes à la fréquence de l'énergie obsorbée

Practical Considerations for Non-Blocking Concurrent Objects

An important class of concurrent objects are those that are non-blocking, that is, whose operations are not contained within mutually exclusive critical sections. A non-blocking object can beaccessed by many threads at a time, yet update protocols based on atomic Compare-And-Swap operations can be used to guarantee the object's consistency. In this paper we take a practical look at the Compare-And-Swap operation in the context of contemporary bus-based shared memory multiprocessors, although our results generalize to distributed shared memory multiprocessors. We first describe an operating system-based solution that permits the construction of a non-blocking Compare-And-Swap function on architectures that only support more primitive atomic primitives such as Test-And-Set or Atomic Exchange. We then evaluate several locking strategies that can be used to synthesize a Compare-And-Swap operation, and show that the common techniques for reducing synchronization overhead in the presence of cont..

Mobisaic

Mobisaic is a World Wide Web information system designed to serve users in a mobile wireless computing environment. Mobisaic extends the Web by allowing documents to both refer and react to potentially changing contextual information, such as one's current location in the wireless network. Mobisaic relies on client-side processing of HyperText Markup Language documents that support two new concepts: Dynamic Uniform Resource Locators (URLs) and Active Documents. A dynamic URL is one whose results depend upon the state of the user's mobile context at the time it is resolved. An active document automatically updates its contents in response to changes in a user's mobile context. This paper describes the design of Mobisaic, the mechanism it uses for representing a user's mobile context, and the extensions made to the syntax and function of Uniform Resource Locators and HyperText Markup Language documents to support mobility. Mobisaic: An Information System for a Mobile Wireless Computing..