Accurate anomaly detection through parallelism

In this article we discuss the design and implementation of a real-time parallel anomaly detection system. The key idea is to use multiple existing anomaly detection algorithms in parallel on thousands of network traffic subclasses, which not only enables us to detect hidden anomalies but also to increase the accuracy of the system. The main challenge then is the management and aggregation of the vast amount of data generated. We propose a novel aggregation process that uses the internal continuous anomaly metrics used by the algorithms to output a single system-wide anomaly metric. The evaluation on real-world attack traces shows a lower false positive rate and false negative rate than any individual anomaly detection algorithm.     

A 640-Mb/s 2048-bit programmable LDPC decoder chip

A 14.3-mm/sup 2/ code-programmable and code-rate tunable decoder chip for 2048-bit low-density parity-check (LDPC) codes is presented. The chip implements the turbo-decoding message-passing (TDMP) algorithm for architecture-aware (AA-)LDPC codes which has a faster convergence rate and hence a throughput advantage over the standard decoding algorithm. It employs a reduced complexity message computation mechanism free of lookup tables, and features a programmable network for message interleaving based on the code structure. The chip decodes any mix of 2048-bit rate-1/2 (3,6)-regular AA-LDPC codes in standard mode by programming the network, and attains a throughput of 640 Mb/s at 125 MHz for 10 TDMP-decoding iterations. In augmented mode, the code rate can be tuned up to 14/16 in steps of 1/16 by augmenting the code. The chip is fabricated in 0.18-/spl mu/m six-metal-layer CMOS technology, operates at a peak clock frequency of 125 MHz at 1.8 V (nominal), and dissipates an average power of 787 mW.     

An MLSE Receiver for Electronic Dispersion Compensation of OC-192 Fiber Links

A maximum-likelihood sequence estimation (MLSE) receiver is fabricated to combat dispersion/intersymbol interference (chromatic and polarization mode), noise (optical and electrical), and nonlinearities (e.g., fiber, receiver photodiode, or laser) in OC-192 metro and long-haul links. The MLSE receiver includes a variable gain amplifier with 40-dB gain range and 7.5-GHz 3-dB bandwidth, a 12.5-Gb/s 4-bit analog-to-digital converter, a dispersion-tolerant phase-locked loop, a 1:8 demultiplexer, and a digital equalizer implementing the MLSE algorithm. The MLSE receiver achieves more than 50% reach extension at signal-to-noise levels of interest as compared to conventional clock data recovery systems     

Mixed Copper/Copper‐Oxide Anchored Mesoporous Fullerene Nanohybrids as Superior Electrocatalysts toward Oxygen Reduction Reaction

Developing a highly active, stable, and efficient non‐noble metal‐free functional electrocatalyst to supplant the benchmark Pt/C‐based catalysts in practical fuel cell applications remains a stupendous challenge. A rational strategy is developed to directly anchor highly active and dispersed copper (Cu) nanospecies on mesoporous fullerenes (referred to as Cu‐MFC₆₀) toward enhancing oxygen reduction reaction (ORR) electrocatalysis. The preparation of Cu‐MFC₆₀ involves i) the synthesis of ordered MFC₆₀ via the prevalent nanohard templating technique and ii) the postfunctionalization of MFC₆₀ with finely distributed Cu nanospecies through incipient wet impregnation. The concurrence of Cu and cuprous oxide nanoparticles in the as‐developed Cu‐MFC₆₀ samples through relevant material characterizations is affirmed. The optimized ORR catalyst, Cu(15%)‐MFC₆₀, exhibits superior electrocatalytic ORR characteristics with an onset potential of 0.860 vs reversible hydrogen electrode, diffusion‐limiting current density (?5.183 mA cm^?2), improved stability, and tolerance to methanol crossover along with a high selectivity (four‐electron transfer). This enhanced ORR performance can be attributed to the rapid mass transfer and abundant active sites owing to the synergistic coupling effects arising from the mixed copper nanospecies and the fullerene framework.     

Stairway to Stereoisomers: Engineering Short- and Medium-Chain Ketoreductases To Produce Chiral Alcohols

The short- and medium-chain dehydrogenase/reductase superfamilies are responsible for most chiral alcohol production in laboratories and industries. In nature, they participate in diverse roles such as detoxification, housekeeping, secondary metabolite production, and catalysis of several chemicals with commercial and environmental significance. As a result, they are used in industries to create biopolymers, active pharmaceutical intermediates (APIs), and are also used as components of modular enzymes like polyketide synthases for fabricating bioactive molecules. Consequently, random, semi-rational and rational engineering have helped transform these enzymes into product-oriented efficient catalysts. The rise of newer synthetic chemicals and their enantiopure counterparts has proved challenging, and engineering them has been the subject of numerous studies. However, they are frequently limited to the synthesis of a single chiral alcohol. The study attempts to defragment and describe hotspots of engineering short- and medium-chain dehydrogenases/reductases for the production of chiral synthons.     

Algorithms Transformation Techniques for Low-Power Wireless VLSI Systems Design

This paper presents an overview of algorithmtransformation techniques and discusses their role inthe development of hardware-efficient and low-power VLSIalgorithms and architectures for communication systems. Algorithm transformation techniquessuch as retiming, look-ahead and relaxed pipelining,parallel processing, folding, unfolding, and strengthreduction are described. These techniques are applied statically (i.e., during the system designphase) and hence are referred to as static algorithmtransformations (SATs). SAT techniques alter thestructural and functional properties of a givenalgorithm so as to be able to jointly optimizeperformance measures in the algorithmic (signal-to-noiseratio [SNR] and bit error rate [BER]) and VLSI (powerdissipation, area and throughput) domains. Next, a new class of algorithm transformations referred toas dynamic algorithm transformations (DAT) is presented.These transformations exploit the nonstationarity in theinput signal environment to determine and assign minimum computational requirements foran algorithm in real time. Both SAT and DAT techniquesare poised to play a critical role in the development oflow-power wireless VLSI systems given the trend toward increasing digital signal processing inthese systems.     

A voltage overscaled low-power digital filter IC

In this brief, we present an integrated circuit implementation of a low-power digital filter in 0.35-/spl mu/m 3.3-V CMOS process. The low-power technique combines voltage overscaling (VOS) and algorithmic noise tolerance (ANT) to push the limits of energy efficiency beyond that achievable by voltage scaling alone. VOS refers to scaling the supply voltage beyond the limit imposed by the throughput constraints. ANT is an algorithmic level error-control technique that is employed to restore the algorithmic performance degradation in terms of output signal-to-noise ratio (SNR) caused by VOS. Measured results indicate 40%-67% reduction in energy dissipation over optimally voltage-scaled systems with less than 1-dB loss in SNR for a wide range of filter bandwidths (0.05f/sub s/-0.25f/sub s/, where f/sub s/ is the sampling frequency).     

A pipelined adaptive NEXT canceller

A near-end crosstalk (NEXT) canceller using a fine-grain pipelined architecture is presented. The performance of the proposed pipelined NEXT canceller is demonstrated in the 125 Mb/s twisted-pair distributed data interface and 155.52 Mb/s asynchronous transfer mode local area network applications. In addition, we analyze the computational complexity of the proposed pipelined NEXT canceller. It is shown that this architecture can be clocked at a rate that is 107 times faster than the serial architecture with a maximum loss of 2.0 dB in signal-to-noise ratio (SNR)     

e-Science, caGrid, and Translational Biomedical Research

Translational research projects target a wide variety of diseases, test many different kinds of biomedical hypotheses, and employ a large assortment of experimental methodologies. Diverse data, complex execution environments, and demanding security and reliability requirements make the implementation of these projects extremely challenging and require novel e-Science technologies.     

Inhibition effects of some Schiff’s bases on the corrosion of mild steel in hydrochloric acid solution

The corrosion inhibition effect of 4-{[(1Z)-(2-chloroquinolin-3-yl)methylene]amino} phenol (CAP), N-[(1Z)-(2-chloroquinolin-yl)methylene]-N-(4-methoxyphenyl)amine (CMPA) and N-[(1E)-(2-chloroquinolin-3-yl)methylene]-N-(4-nitrophenyl)amine (CNPA) on mild steel in 1.0 M HCl has been investigated using mass loss, polarization and electrochemical impedance techniques at 300 K. The inhibition efficiencies increased with increase in inhibitors concentration. Polarization studies showed that the inhibitors are of predominantly cathodic character. Among the three compounds studied, CAP exhibited the best performance giving more than 97% IE. Some samples of mild steel were examined by SEM. All the inhibitors were found to adsorb on the mild steel surface according to the Langmuir adsorption isotherm.