Synchronous Multiparty Session Types

AbstractSynchronous communication is useful to model multiparty sessions where control for timing events and strong sequentially order of messages are essential to the problem specification. This paper continues the work on multiparty session types initiated by Honda et al. [Honda, K., N. Yoshida and M. Carbone, Multiparty asynchronous session types, in: G. C. Necula and P. Wadler, editors, POPL (2008), pp. 273–284] for synchronous communications. It provides a more relaxed syntax of the calculus, multicasting, higher-order communication via multipolarity labels and a clear definition of delegation in global types. The linearity property defines when a channel can be used in two different communications without creating a race condition and the type system checks if all the processes of a session implement the communication behavior specified in the global type. The type system of the calculus is proved to be sound with respect to the operational semantics and coherent with respect to the global types

Parameterised Multiparty Session Types

For many application-level distributed protocols and parallel algorithms, the set of participants, the number of messages or the interaction structure are only known at run-time. This paper proposes a dependent type theory for multiparty sessions which can statically guarantee type-safe, deadlock-free multiparty interactions among processes whose specifications are parameterised by indices. We use the primitive recursion operator from G\"odel's System T to express a wide range of communication patterns while keeping type checking decidable. To type individual distributed processes, a parameterised global type is projected onto a generic generator which represents a class of all possible end-point types. We prove the termination of the type-checking algorithm in the full system with both multiparty session types and recursive types. We illustrate our type theory through non-trivial programming and verification examples taken from parallel algorithms and Web services usecases.Comment: LMCS 201

Computerization of analogue data of earthquakes in Albania

This paper deals with computerization of the analogue data on the seismicityin Albania by developing a database. Since ancient time Albania has beenpermanently affected by earthquakes, even though their magnitude has not beenmaximal. Albania is considered to be in the group of European countries withhigher number of earthquakes per time unit. The release of the earthquake energyhas mostly happened through micro-earthquakes (M<3.0), weak earthquakes(3.0<M<5.5) and the ones of middle magnitude (5.5<M<7.0). Earthquakes with amagnitude of 7.0 have been very rare, the intensity at the epicentre being 10. Theseismic hazard can be determined by applying both deterministic and probabilisticmethods. This paper deals with the probabilistic method which uses the statisticaldistribution in a region based on the earthquakes having occurred in the past. Such amethod provides evaluations of probabilities for various intensity levels. Thedatabase to be prepared will serve to digitize the parameters that describe theseismic activity in Albania. It will use the existing material which has been recordedby the analogue seismological network of Albania. The information whichaccompanies the earthquakes includes, date and exact time, geographic coordinates,depth to the focus/hypocenter, magnitude (Richter), intensity and epicentre. Thedatabase allows the data to be edited and searching in accordance with the user's needs. It will determine the earthquake characteristics for a certain administrativeunit, characteristics according to the magnitude, classifying them as micro-earthquakes,weak and mid-intensity ones, or according to coordinates, focus depth,intensity etc. The database will be accompanied with reports which will reflect these ismicity for the entire Albania for a certain period of time, the earthquakedistribution according to the magnitude, the earthquake frequency graphs etc. It willalso serve as a basis for additional new information and its linkage with othersoftware of the system. This database will contribute to have a better judgment onthe seismic activity in Albania and expectations on future events

Bottom up effects of nutrients and water on black vine weevil Otiorhynchus sulcatus (Coleoptera: Curculionidae) and Heuchera micrantha "Palace Purple" (Saxifragacea)

This thesis investigated: a) the effect of fertilization and water regimes on chemistry and growth of Heuchera micrantha and the effect of plant quality on black vine weevil performance b) the effect of black vine weevil larvae on Heuchera micrantha growth and c) the effect of fertilization on tolerance of Heuchera micrantha plants to different densities of black vine weevil. I found a positive effect of nitrogen fertilization and water on plant chemistry and growth. Leaf nitrogen, carbon: nitrogen ratio, and phenols were strongly affected by nitrogen fertilization. Fertilization had no effect on adult and larval survivorship, ovipositional period or feeding preference of black vine weevil adult. Larvae had a strong effect on top and root biomass and this effect increased with increasing levels of fertilizer when water was not limited. Fertilizer did not increase tolerance of Heuchera micrantha to adults or larvae of black vine weevil