Colored Petri nets offer a compact and user friendly representation of the traditional Place/Transition (P/T) nets and colored nets with finite color ranges can be unfolded into the underlying P/T nets, however, at the expense of an exponential explosion in size. We present two novel techniques based on static analysis in order to reduce the size of unfolded colored nets. The first method identifies colors that behave equivalently and groups them into equivalence classes, potentially reducing the number of used colors. The second method overapproximates the sets of colors that can appear in places and excludes colors that can never be present in a given place. Both methods are complementary and the combined approach allows us to significantly reduce the size of multiple colored Petri nets from the Model Checking Contest benchmark. We compare the performance of our unfolder with state-of-the-art techniques implemented in the tools MCC, Spike and ITS-Tools, and while our approach is competitive w.r.t. unfolding time, it also outperforms the existing approaches both in the size of unfolded nets as well as in the number of answered model checking queries from the 2021 Model Checking Contest.

Traditionally, the development workflow of Arrow-head applications is based on the usage of source code skeletons. This makes it difficult to update applications when the skeletons are changed, for example to fix security vulnerabilities or add new functionality. In fact, to update an application the developer has to either recreate the application on the new skeleton version or recreate the skeleton changes on the previous version of the application. Instead, we propose a client library, which allows the developers to create Arrowhead applications by referring to a library. Not only does this allow the Arrowhead Consortium to update the library without requiring changes to applications, it also eases the creation of new Arrowhead applications, reduces code duplication and increases readability. This paper describes the design and the structure of this client library, provides insights on how to employ the library in applications, and surveys a few sample applications that use the library.

Floor heating systems are important components of nowadays home-automation setups. The control of a floor heating system is a nontrivial task and the present solutions essentially implement variants of a simple bang-bang controller that opens for a hot water circulation in a room if its current temperature is below the user defined target temperature, otherwise it closes for the heating in the room. The disadvantage is that the heat exchange among the rooms, outside weather conditions, weather forecast and other factors are not considered. We propose a novel model-driven approach for intelligent floor heating control based on a chain of tools that allow us to gather the sensor readings from the actual hardware and use the state-of-the-art controller synthesis tool UPPAAL Stratego in order to synthesise abstract control strategies that are then executed on the real hardware platform provided by the company Seluxit. We have built a scaled demonstrator of the system and the experimental results document a 38% to 52 % increase in user satisfaction, moreover with additional energy savings between 2% to 12%.

A smart house is a complex system, and configuring it to act as desired is difficult and error prone. In this paper we extend a previously developed framework based on timed automata for designing safe and reliable home automation scenarios to make it easier to use. To do so we abstract it with an Event-Condition-Action language to create intelligent scenarios, and constraints that prevent scenarios with undesirable behaviours to be applied. This language is itself abstracted by a graphical user interface that enables the creation of scenarios by manipulating graphical blocks representing elements of the language. We have designed and implemented a prototype system to test our approach, and we report on a qualitative user study that was conducted.

Secure multiparty protocols have been proposed to enable noncolluding parties to cooperate without a trusted server. Even though such protocols prevent information disclosure other than the objective function, they are quite costly in computation and communication. The high overhead motivates parties to estimate the utility that can be achieved as a result of the protocol beforehand. In this paper, we propose a look-ahead approach, specifically for secure multiparty protocols to achieve distributed k-anonymity, which helps parties to decide if the utility benefit from the protocol is within an acceptable range before initiating the protocol. The look-ahead operation is highly localized and its accuracy depends on the amount of information the parties are willing to share. Experimental results show the effectiveness of the proposed methods.