RADE: resource-efficient supervised anomaly detection using decision tree-based ensemble methods

Machine Learning - The capability to perform anomaly detection in a resource-constrained setting, such as an edge device or a loaded server, is of increasing need due to emerging on-premises...     

Suppressing meta-holographic artifacts by laser coherence tuning

A metasurface hologram combines fine spatial resolution and large viewing angles with a planar form factor and compact size. However, it suffers coherent artifa...     

Interfacial Characterization of Epoxy-bonded Maraging Steel

Adhesion phenomena involving polymer-metal interfaces have become a central subject for research and technological development, especially in view of adhesive bonding of metallic components in primary load-bearing structures. Since adhesion implies that some sort of chemical and/or physical interactions take place between the metal adherend and the polymeric adhesive, a great deal of attention has been devoted to identification and characterization of such interactions and to the development of techniques to study them. Among the most widely used methods for interfacial studies are: ESCA (Electron Spectroscopy for Chemical Analysis), AES (Auger Electron Spectroscopy), SIMS (Secondary Ion Mass Spectroscopy), IR spectroscopy, optical microscopy, and electron microscopy.     

Several basic and practical aspects related to electrochemical deionization of water

We examine water desalination processes based on the electrosorption of ions onto activated carbon electrodes (capacitive deionization, CDI). A flow‐by operation mode was used (solutions flows within channels in the separator, parallel to the electrodes) in both continuous and stopped flow experiments. The different response of solutions containing more than 5000 ppm NaCl and dilute solutions (e.g., 1000 ppm NaCl) to the applied potential is discussed. The electrical current transients on potential steps were faster by two orders of magnitude than the resulting concentration transients due to the dynamics of these deionization processes and the properties of the cells used herein. Guidelines for the practical development of capacitive water deionization processes are discussed herein. It is assumed that for brackish water containing several thousands ppms of NaCl, CDI may be advantageous over competitive methods (e.g., reverse osmosis). © 2009 American Institute of Chemical Engineers AIChE J, 2010     

The effect of working memory capacity limitations on the intuitive assessment of correlation: Amplification, attenuation, or both?

This article challenges Yaakov Kareev's (1995a, 2000) argument regarding the positive bias of intuitive correlation estimates due to working memory capacity limitations and its adaptive value (see record 1995-39555-001 and record 2000-15248-009). The authors show that, under narrow window theory's primacy effect assumption, there is a considerable between-individual variability of the effects of capacity limitations on the intuitive assessment of correlation, in terms of both sign and magnitude: Limited capacity acts as an amplifier for some individuals and as a silencer for others. Furthermore, the average amount of attenuation exceeds the average amount of amplification, and the more so, the smaller the capacity. Implications regarding the applicability and contribution of the bias notion in this context and the evaluation of the adaptive value of capacity limitations are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Accurate discovery of co-derivative documents via duplicate text detection

Documents are co-derivative if they share content: for two documents to be co-derived, some portion of one must be derived from the other, or some portion of both must be derived from a third document. An existing technique for concurrently detecting all co-derivatives in a collection is document fingerprinting, which matches documents based on the hash values of selected document subsequences, or chunks. Fingerprinting is hampered by an inability to accurately isolate information that is useful in identifying co-derivatives. In this paper we present spex, a novel hash-based algorithm for extracting duplicated chunks from a document collection. We discuss how information about shared chunks can be used for efficiently and reliably identifying co-derivative clusters, and describe deco, a prototype package that combines the spex algorithm with other optimisations and compressed indexing to produce a flexible and scalable co-derivative discovery system. Our experiments with multi-gigabyte document collections demonstrate the effectiveness of the approach.     

Bug Attacks

In this paper we present a new kind of cryptanalytic attack which utilizes bugs in the hardware implementation of computer instructions. The best-known example of such a bug is the Intel division bug, which resulted in slightly inaccurate results for extremely rare inputs. Whereas in most applications such bugs can be viewed as a minor nuisance, we show that in the case of RSA (even when protected by OAEP), Pohlig–Hellman and ElGamal encryption such bugs can be a security disaster: decrypting ciphertexts on any computer which multiplies even one pair of numbers incorrectly can lead to full leakage of the secret key, sometimes with a single well-chosen ciphertext. As shown by recent revelation of top secret NSA documents by Edward Snowden, intentional hardware modifications is a method that was used by the USA to weaken the security of commercial equipment sent to targeted organizations.     

Silicon-Rich Higher Manganese Silicides for Thermoelectric Applications

Thermoelectrics are widely explored as a renewable and environmentally friendly method for converting waste heat to electrical power. Higher manganese silicides (HMS) have been identified as promising, nontoxic, inexpensive, p-type materials for thermoelectric applications. To mass-produce practical thermoelectric converters, an inexpensive, effective, and simple production method should be applied for these materials. In the frame of the current research, HMS have been synthesized using furnace melting followed by powdering and spark plasma sintering. Highly dense samples were obtained and measured for their thermoelectric properties. The samples were also characterized using x-ray diffraction, scanning electron microscopy, and Hall-effect measurements. Homogeneous samples were obtained with small inclusions of Si, reaching a figure of merit of about 0.6 at 450°C.     

Avoiding the approach trap: A response bias theory of the emotional Stroop effect.

In the laboratory, people classify the color of emotion-laden words slower than they do that of neutral words, the emotional Stroop effect. Outside the laboratory, people react to features of emotion-laden stimuli or threatening stimuli faster than they do to those of neutral stimuli. A possible resolution to the conundrum implicates the counternatural response demands imposed in the laboratory that do not, as a rule, provide for avoidance in the face of threat. In 2 experiments we show that when such an option is provided in the laboratory, the response latencies follow those observed in real life. These results challenge the dominant attention theory offered for the emotional Stroop effect because this theory is indifferent to the vital approach–avoidance distinction. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A Comparison Between the Mechanical and Thermoelectric Properties of Three Highly Efficient p-Type GeTe-Rich Compositions: TAGS-80, TAGS-85, and 3% Bi2Te3-Doped Ge0.87Pb0.13Te

Since the 1960s, the TAGS system, namely (GeTe) _x (AgSbTe₂)_1?x , with two specific compositions x = 0.8 and 0.85, known as TAGS-80 and TAGS-85, respectively, was identified as containing highly efficient p-type thermoelectric materials. Recently, another highly efficient p-type GeTe-rich composition, namely 3% Bi₂Te₃-doped Ge_0.87Pb_0.13Te, achieving thermoelectric properties comparable to TAGS-based solid solutions, was also reported. Since all of these compositions were obtained by different manufacturing approaches, a comparison between the transport and mechanical properties of these alloys, prepared by the same manufacturing techniques, is required to identify the advantages and disadvantages of these compositions for practical thermoelectric applications. In the current research, the thermoelectric and mechanical properties of three highly efficient GeTe-rich alloys, TAGS-80, TAGS-85, and 3% Bi₂Te₃-doped Ge_0.87Pb_0.13Te, following hot pressing, were investigated and compared. Maximal ZT values of ～1.75, ～1.4, and ～1.6 at 500°C were found for these compositions, respectively. Improvement of the mechanical properties was observed by increasing the GeTe content. The influence of the GeTe relative amount on the transport and mechanical properties was interpreted by means of the phase-transition temperatures from the low-temperature rhombohedral to the high-temperature cubic phases.