Cyber-Physical Systems (CPS) are large interconnected softwareintensive systems that influence, by sensing and actuating, the physical world. Examples are traffic management and power grids. One of the trends we observe is the need to endow such systems with the "smart" capabilities, typically in the form of selfawareness and self-adaptation, along with the traditional qualities of safety and dependability. These requirements combined with specifics of the domain of smart CPS -- such as large scale, the role of end-users, uncertainty, and open-endedness -- render traditional software engineering (SE) techniques not directly applicable; making systematic SE of smart CPS a challenging task. This paper reports on the results of the First International Workshop on Software Engineering of Smart Cyber-Physical Systems (SEsCPS 2015), where participants discussed characteristics, challenges and opportunities of SE for smart CPS, with the aim to outline an agenda for future research in this important area.

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Bell C o m m u n i c a t i o n s Research331 N e w m a n Springs R o a d R e d B a n k , NJ 07728-7020 (201) 758-4065Abstract.The throughput/delay performance of certain type of Spread-Spectrum Random-Access (SSRA) networks employing directional antennas is considered. The use of directional antennas in the receiving sites to improve the network performance is presented and analyzed. The basic idea is to reduce the contention of the users (transmitters), by dividing the coverage area into different regions; at the receiving site, a single directional antenna is aimed at one region, so t h a t transmissions from different regions do not interfere with each other. In addition to the reduction of the multiuser interference, the directional antennas allow for different classifications, in different regions, of the users according to their physical and link level parameters.Numerical results for performance comparison with the case of receivers using omnidirectional antennas are also included. 1.Introduction.Since the time when the ALOHA network [Abra70], the first operational example of multiple-access radio for d a t a communications, was realized, much work has been done on improving its throughput/delay [KlLa75] performance. The introduction of spread-spectrum [IEEE77], [IEEE82], as a modulation and access tool in these networks [KaGr78], motivated mostly by military applications, and its impact on the throughput/delay performance of SSRA networks has received wide attention in the last decade (see [DaGr80], [RaycBl], [Hui84] and references therein). Different methods for improvement on the network performance have been considered [Toba87], [IEEE85]. In general, throughput/delay performance improvement can be achieved by means of Forward Error Correction (FEC) coding, and sometimes spreading, [PoSi87], [Rayc81], [Purs87], variations in the access parameters [HaVa82], [Haje82], [MeKa85] or a combination of the above along with power level diversity [PoKe87].Most of the published research in this area addressed simple topologies, which resulted in throughput/delay expressions which were obtained in a fairly straightforward manner.In [PoSi87], throughput/delay performance evaluation for more complex topologies has been performed, still under some assumptions. Always the users were assumed t o be sharing a common channel by employing omnidirectional antennas both in the transmitting and the receiving sites. More recently, [LaLe88a], [LaLe88b], a method which makes use of directional antennas in a mobile radio environment was proposed, for unspread, uncoded, noiseless slotted ALOHA-type networks.In this paper, we examine the impact which receivers with directional antennas have on the performance of SSRA networks. In particular, we consider monohop networks, subject t o AWGN, where each physical receiver employs multiple directional antennas and has multicode receiving capability. In [PoSi87], a convenient analytic model for a certain class of "local" or "monohop" was introduced. Using this model as a starting point, w...

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