Forward and Reverse Converters and Moduli Set Selection in Signed-Digit?Residue?Number?Systems

This paper presents an investigation into using a combination of two alternative digital number representations; the residue number system (RNS) and the signed-digit (SD) number representation in digital arithmetic circuits. The combined number system is called RNS/SD for short. Since the performance of RNS/SD arithmetic circuits depends on the choice of the moduli set (a set of pairwise prime numbers), the purpose of this work is to compare RNS/SD number systems based on different sets. Five specific moduli sets of different lengths are selected. Moduli-set-specific forward and reverse RNS/SD converters are introduced for each of these sets. A generic conversion technique for moduli sets consisting of any number of elements is also presented. Finite impulse response (FIR) filters are used as reference designs in order to evaluate the performance of RNS/SD processing. The designs are evaluated with respect to delay and circuit area in a commercial 0.13 μm CMOS process. For the case of FIR filters it is shown that generic moduli sets with five or six moduli results in designs with the best area × delay products.

Adhesion and Mechanical Properties of PNIPAM Microgel Films and Their Potential Use as Switchable Cell Culture Substrates

Thermoresponsive poly(N‐isopropylacrylamide) (PNIPAM) microgel films are shown to allow controlled detachment of adsorbed cells via temperature stimuli. Cell response occurs on the timescale of several minutes, is reversible, and allows for harvesting of cells in a mild fashion. The fact that microgels are attached non‐covalently allows using them on a broad variety of (charged) surfaces and is a major advantage as compared to approaches relying on covalent attachment of active films. In the following, the microgels’ physico‐chemical parameters in the adsorbed state and their changes upon temperature variation are studied in order to gain a deeper understanding of the involved phenomena. By means of atomic force microscopy (AFM), the water content, mechanical properties, and adhesion forces of the microgel films are studied as a function of temperature. The analysis shows that these properties change drastically when crossing the critical temperature of the polymer film, which is the basis of the fast cell response upon temperature changes. Furthermore, nanoscale mechanical analysis shows that the films posses a nanoscopic gradient in mechanical properties.     

Experimental validation of the linear drive train for a total artificial heart system

In industrialized countries cardiovascular diseases are the major cause of death. Beside heart transplants, which are a limited option due to the limited number of available human donor hearts, Total Artificial Hearts (TAHs) are the only therapy available for some patients with terminal heart diseases. For various reasons a total implantable artificial heart is desirable, but also sets restrictions in terms of weight and dimensions due to the limited space in the human thorax. Therefore a precise requirement profile is needed for the drive design to provide sufficient force for the blood pump and to avoid oversizing of the drive and to prevent blood damage by overheating.     

An overview of state of the art and research in the fields of sensible, latent and thermo-chemical thermal energy storage

Due to the increase in volatile renewable power and heat generation (wind or solar), thermal energy storage (TES) has obtained growing importance and interest. The technology can be distinguished into three main types: sensible, latent and thermochemical storage. Apart from low and medium temperature heat applications, high temperature TES also is an attractive means to store power in the form of heat (before the thermodynamic transformation process). Thermochemical storage allows for long duration seasonal storage of energy.     

Performance analysis of partially coherent SSD systems

The performance analysis of a system employing co-ordinate interleaving and constellation rotation, over Nakagami-m fading channels, in the presence of phase noise as well as additive white Gaussian noise, is presented. An upper bound for the average probability of bit error for M-ary phase shift keying is derived. It is shown that the derived upper bound is tight for high signal-to-noise ratios and in the presence of phase noise the optimum rotation angle does not change. Furthermore, it is shown that a system employing co-ordinate interleaving and constellation rotation is more robust against phase estimation errors.     

Reliability of gate dielectrics and metal–insulator–metal capacitors

In this review paper reliability characterisation methods of SiO₂ as gate dielectric and metal–insulator–metal capacitors with various dielectrics are discussed. It includes the test structure design, the stress and measurement sequences, the raw data analysis and the extrapolation models of measured time to breakdown to lifetimes at operating conditions and targeted product failure rates. For each topic various references are given where further details are described. Especially pitfalls of approaches and problem areas are highlighted.     

Outdoor scene image segmentation based on background recognition and perceptual organization

In this paper, we propose a novel outdoor scene image segmentation algorithm based on background recognition and perceptual organization. We recognize the background objects such as the sky, the ground, and vegetation based on the color and texture information. For the structurally challenging objects, which usually consist of multiple constituent parts, we developed a perceptual organization model that can capture the nonaccidental structural relationships among the constituent parts of the structured objects and, hence, group them together accordingly without depending on a priori knowledge of the specific objects. Our experimental results show that our proposed method outperformed two state-of-the-art image segmentation approaches on two challenging outdoor databases (Gould data set and Berkeley segmentation data set) and achieved accurate segmentation quality on various outdoor natural scene environments.     

Fabrication of Anticounterfeiting Nanocomposites with Multiple Security Features via Integration of a Photoresponsive Polymer and Upconverting Nanoparticles

Anticounterfeiting materials are used to distinguish real banknotes, products, and documents from counterfeits, fakes, or unauthorized replicas. However, conventional anticounterfeiting materials generally exhibit a single anticounterfeiting function, resulting in a low level of security. Herein, a novel anticounterfeiting nanocomposite is demonstrated with numerous prominent security features. The nanocomposite is fabricated by doping upconverting nanoparticles (UCNPs) in a photoresponsive azobenzene-containing polymer (azopolymer). Because of the cis–trans photoisomerization of the azopolymer, the nanocomposite exhibits photoinduced reversible color changes suitable for anticounterfeiting applications. Additionally, the hard nanocomposite can be converted to a rubber-like soft solid by light irradiation. Imprinted microstructures are fabricated on the photosoftened nanocomposite, which result in photonic colors. Moreover, polarization-dependent structures are fabricated on the nanocomposite via photoinduced orientation for encryption. Importantly, UCNPs in the nanocomposite emit visible light upon excitation by near-infrared light, enabling the observation of various anticounterfeiting structures with high contrast. An advantage of the anticounterfeiting nanocomposite is that the security features can be observed by the naked eye for quick discrimination and can be analyzed using laboratory equipment for higher accuracy. The anticounterfeiting nanocomposite is easily processed on paper, glass, and plastic, which demonstrates its potential anticounterfeiting functions for banknotes, wines, and medicines.     

Weak Locking Capacity of Quantum Channels Can be Much Larger Than Private Capacity

We show that it is possible for the so-called weak locking capacity of a quantum channel (Guha et al. in Phys Rev X 4:011016, 2014) to be much larger than its private capacity. Both reflect different ways of capturing the notion of reliable communication via a quantum system while leaking almost no information to an eavesdropper; the difference is that the latter imposes an intrinsically quantum security criterion whereas the former requires only a weaker, classical condition. The channels for which this separation is most straightforward to establish are the complementary channels of classical-quantum (cq-)channels and, hence, a subclass of Hadamard channels. We also prove that certain symmetric channels (related to photon number splitting) have positive weak locking capacity in the presence of a vanishingly small pre-shared secret, whereas their private capacity is zero. These findings are powerful illustrations of the difference between two apparently natural notions of privacy in quantum systems, relevant also to quantum key distribution: the older, naïve one based on accessible information, contrasting with the new, composable one embracing the quantum nature of the eavesdropper’s information. Assuming an additivity conjecture for constrained minimum output Rényi entropies, the techniques of the first part demonstrate a single-letter formula for the weak locking capacity of complements to cq-channels, coinciding with a general upper bound of Guha et al. for these channels. Furthermore, still assuming this additivity conjecture, this upper bound is given an operational interpretation for general channels as the maximum weak locking capacity of the channel activated by a suitable noiseless channel.