We present a new construction of divisible e-cash that makes use of 1) a new generation method of the binary tree of keys; 2) a new way of using bounded accumulators. The transaction data sent to the merchant has a constant number of bits while spending a monetary value 2. Moreover, the spending protocol does not require complex zero-knowledge proofs of knowledge such as proofs about double dis...

In this paper we are interested in privacy preserving discretionary access control (DAC) for outsourced storage such as increasingly popular cloud storage services. Our main goal is to enable clients, who outsource data items, to delegate permissions (read, write, delete) to other clients such that clients are able to unlinkably and anonymously perform operations on outsourced data items when h...

The addition of two or more floating-point numbers is fundamental to numerical computations. This paper describes an efficient “distillation” style algorithm which produces a precise sum by exploiting the natural accuracy of compensated cancellation. The algorithm is applicable to all sets of data but is particularly appropriate for ill-conditioned data, where standard methods fail due to the a...

Cox and Shiffrin (2012) introduced a dynamic model of recognition memory that was capable of making simultaneous predictions for accuracy and mean response time. The present paper extends that work by investigating the assumptions underlying the model’s decision process, in particular those pertaining to the process by which features are sampled at test and the processes by which evidence for a...

Consider a constraint on a sequence of variables functionally determining a result variable that is unchanged under reversal of the sequence. Most such constraints have a compact encoding via an automaton augmented with accumulators, but it is unknown how to maintain domain consistency efficiently for most of them. Using such an automaton for such a constraint, we derive an implied constraint b...

Autonomous working systems are used in maritime research in different fields of application already for decades. Often it is not possible to keep a permanent connection with a cable. This stems from the depth of missions up to 6000 meters, difficult reachable locations or mission periods of several months. Generally, the power supply of such systems can be guaranteed with accumulators only. Alt...

We conducted a clinical audit by observing 55 vaccinators in schools in the governorate of Monastir in 2014. We used a set of criteria by referring to the national immunization programme. The cold chain was respected in most cases. Accumulators, the collector of syringes and needles, cotton balls soaked in alcohol and emergency box were available in 85.5%, 76.4%, 98.2% and 41.8% of cases respec...

We propose a digital signature scheme for dynamic coalitions. Particularly, we enable members to join and leave. Our scheme does not need trusted or oblivious third parties (TTPs or OTPs). In this distributed scheme there is a changing secret group key dependent on the members in the group. Each member’s secret key remains the same for all group compositions. The downside of this approach is th...

The pollution of aquatic ecosystems is an issue facing many countries all over the world and may result in issues such as eutrophication coastal zones. Managing this a real challenge. current study focuses on investigation identification environmental characteristics, including sediments, waters, seaweed, seven eutrophicated locations along Mediterranean coast Alexandria (Egypt). Different ecol...