Expanded glass particles (EGP) have been used to manufacture Al syntactic foams using a simple vacuum casting method. Clamping of the casting in the stainless steel mould was observed when preheating the mould to >400°C, causing damage to the EGP, resulting in a weaker foam but with the significant advantage of eliminating the yield drop, improving the energy absorption characteristics. The same effect in castings that were not clamped (for mould preheats < 400°C) could be achieved by quenching in liquid nitrogen. These "low strength" syntactic metal foams are a costeffective alternative to metal foams and porous metals (in terms of specific strength, stiffness and energy absorption) rather than "conventional" syntactic foams which contain smaller, stronger, hollow microspheres.

Despite the relative maturity of the Internet, the computer networks of today are still susceptible to attack. The necessary distributed nature of networks for wide area connectivity has traditionally led to high cost and complexity in designing and implementing secure networks. With the introduction of Software Defined Networks (SDN) and Network Functions Virtualisation (NFV), there are opportunities for efficient network threat detection and protection. SDN's global view provides a means of monitoring and defence across the entire network. However, current SDN-based security systems are limited by a centralised framework that introduces significant control plane overhead, leading to the saturation of vital control links. In this paper, we introduce TENNISON, a novel distributed SDN security framework that combines the efficiency of SDN control and monitoring with the resilience and scalability of a distributed system. TENNISON offers effective and proportionate monitoring and remediation, compatibility with widely-available networking hardware, support for legacy networks, and a modular and extensible distributed design. We demonstrate the effectiveness and capabilities of the TENNISON framework through the use of four attack scenarios. These highlight multiple levels of monitoring, rapid detection and remediation, and provide a unique insight into the impact of multiple controllers on network attack detection at scale.

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In this presentation we will discuss the performance and limitations of our 220 channel video rate passive millimeter wave imaging system based on a distributed aperture with optical upconversion architecture. We will cover our efforts to reduce the cost, size, weight, and power (CSWaP) requirements of our next generation imager. To this end, we have developed custom integrated circuit silicon-germanium (SiGe) low noise amplifiers that have been designed to efficiently couple with our high performance lithium niobate upconversion modules. We have also developed millimeter wave packaging and components in multilayer liquid crystal polymer (LCP) substrates which greatly improve the manufacturability of the upconversion modules. These structures include antennas, substrate integrated waveguides, filters, and substrates for InP and SiGe mmW amplifiers.

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