Emerging resistively switching devices are thought to enable ultradense passive nanocrossbar arrays for use as random access memories (ReRAM) by the end of the decade, both for embedded and mass storage applications. Moreover, ReRAMs offer inherent logic‐in‐memory (LIM) capabilities due to the nonvolatility of the devices and therefore great potential to reduce the communication between memory and calculation unit by alleviating the so‐called von Neumann bottleneck. A single bipolar resistive switching device is capable of performing 14 of 16 two input logic functions in the logic concept presented by Linn et al. (“CRS‐logic”). In this paper, five types of selectorless devices are considered to validate this CRS‐logic concept is experimentally by means of the IMP and AND logic operations. As reference device a TaO x ‐based ReRAM cell is considered, which is compared to three more advanced device configurations consisting either of a threshold supported resistive switch (TS‐ReRAM), a complementary switching device (CS), or a complementary resistive switch (CRS). It is shown that all of these devices offer the desired LIM behavior. Moreover, the feasibility of XOR and XNOR operations using a modified logic concept is applied for both CS and CRS devices and the pros and cons are discussed.

As part of a European collaborative project, four high-speed compressors were tested to investigate the generic features of stall inception in aero-engine type compressors. Tests were run over the full speed range to identify the design and operating parameters that influence the stalling process. A study of data analysis techniques was also conducted in the hope of establishing early warning of stall. The work presented here is intended to relate the physical happenings in the compressor to the signals that would be received by an active stall control system. The measurements show a surprising range of stall-related disturbances and suggest that spike-type stall inception is a feature of low-speed operation while modal activity is clearest in the midspeed range. High-frequency disturbances were detected at both ends of the speed range and nonrotating stall, a new phenomenon, was detected in three out of the four compressors. The variety of the stalling patterns, and the ineffectiveness of the stall warning procedures, suggests that the ultimate goal of a flightworthy active control system remains some way off.

Rapid growth of future information technology depends on energy‐efficient computation and ultra‐high density data storage. Non‐volatile redox‐based resistive switching memory (ReRAM) devices offer logic‐in‐memory capabilities and can redefine the von Neumann computer architecture. Especially complementary resistive switches (CRSs) enable the integration of highly dense passive nano‐crossbar arrays in 4F2 structure (F is the minimum feature size) without the need of selector devices. To reduce fabrication complexity further, single ReRAM device in complementary switching (CS) mode is a viable option. Here, the implementation of in‐memory‐adders using Pt|HfO2|Hf|Pt‐based CS devices, which are integrated into 1 × n passive crossbar arrays, is reported. First, the feasibility of all CRS‐logic functions with these CS devices is shown, which offer high‐endurance (109 cycles) under pulse conditions. Afterward, two multi‐bit crossbar adders, the Toggle‐Cell Adder and the Pre‐Calculation Adder, are experimentally demonstrated under pulse conditions realizing addition and subtraction operations. These results prove the functional efficiency of the crossbar adder approach, paving the path for highly advanced ReRAM‐based computing‐in‐memory architectures.

Ionic transport greatly influences the switching kinetics of filamentary resistive switching memories and depends strongly on temperature and electric fields. To separate the impact of both parameters on the switching kinetics and to further deepen the understanding of the influence of local Joule heating, a nanometer‐sized heating structure is employed. It consists of a 100 nm wide Pt electrode which, due to Joule heating, serves as heating source upon an electrical stimulus. These self‐heating properties are underlined by a 3D finite elements simulation model, which confirms a temperature increase of almost 500 K. Experimental electrical pulse measurements indicate that for this temperature a steady state is achieved in less than 100 ns. By employing this heating structure, kinetic measurements of a Pt/Ta2O5/Ta cell are performed at different temperatures and reveal that significantly decreased SET times are obtained with increasing temperature. This effect is accompanied by an increasing slope of the current prior to the SET event. The experimental results are further confirmed by predictions of an analytical model based on ionic conduction.

Engine/intake compatibility covers the mutual dependencies between the aircraft intake and the gas turbine. Flow physical effects in both the intake and/or the gas turbine can reduce stability margins of the propulsion system dramatically, possibly resulting in unstable performance or engine flameout. Besides exhibiting optimal performance it is of utmost importance that stable propulsion operation in the whole flight envelope of a jet aircraft is ensured. In this chapter, the sources of possible intake flow distortions will be described. The state of the art for the quantification of intake flow distortion by the use of distortion parameters is presented together with possible methods for measuring the data for the calculation of these parameters. Existing experience and current research efforts with the aim of reducing flow distortion in intakes are highlighted.