gebhart/patrepeval huggingface dataset:
Approximate best linear unbiased channel estimation for frequency selective multipath channels with long delay spreads (2004)

We provide an iterative and a non-iterative channel impulse response (CIR) estimation algorithm for communication systems which utilize a periodically transmitted training sequence within a continuous stream of information symbols. The iterative procedure calculates the (semi-blind) best linear unbiased estimate (BLUE) of the CIR. The non-iterative version is an approximation to the BLUE CIR estimate, achieving almost similar performance, with much lower complexity. We first provide a formulation of the received data and correlation processing with the adjacent symbol correlation taken into account, and we then present the connections of the correlation based CIR estimation scheme to the ordinary least squares CIR estimation, and the BLUE CIR estimation. Simulation results are provided to demonstrate the performance of the novel algorithms for 8-VSB ATSC digital TV systems.
New route classification method for networks with static routing (2007)

The paper describes new method for routing classification of the packets in the networks with static routing. Static routing is mostly used in the stable and well-controlled networks, which are sensitive to the additional complexity introduced by the dynamic routing schemes. For example, it is a straightforward choice for the embedded networks on terminal. The available solutions for the static routing require full-size or longest prefix-based aggregated routing table, which is inefficient taking into account static nature of the performed routing decisions. The standard approach is based on the full implementation of the route lookup procedure, which for every packet performs search for the longest prefix match in the routing table. As a result, it increases implementation complexity of the network end points and switches, requires high speed memory for storing routing tables, and leads to an additional processing delay and energy consumption for each transmitted packet. This work is based on the observation that clever planning of the networks with static routing allows applying new principles of route lookup. As a consequence it allows significantly reduce complexity of the packet classification and forwarding procedures and minimize amount of consumed resources. Complexity reduction of the packets classification and forwarding procedures allows simplifying implementation of the networking part of the protocol stack, which results in reduction of the device components cost, decrease of the power and memory consumption, as well as the packet processing delay. The paper contains a description of the proposed route classification method and discusses its applicability for broad range of networks with static routing.
Ex-situ training of dense memristor crossbar for neuromorphic applications (2015)

This study proposes a technique for programming a dense memristor crossbar array without isolation transistors (0T1M) in order to achieve ex-situ training of a neural network. Programming memristors to a specific resistance level requires an iterative process needing the reading of individual memristor resistances due to memristor device stochasticity. This paper presents a circuit to read individual resistances from a 0T1M crossbar and a method to map neuron synaptic weights into a novel neural circuit to enable ex-situ training. The results show that we are able to train the resistances in a 0T1M crossbar and that the 0T1M system is about 93% smaller in area than 1T1M systems.
Overview of recent results from the triggered plasma opening switch experiment (2004)

Summary form only given. The Triggered Plasma Opening Switch (TPOS) at Sandia National Laboratories is a unique device that exploits the high conductance and zero tensile strength of plasma. The purpose of the TPOS is to take the initial /spl sim/.8 MA (/spl sim/250 ns rise time) storage inductor current and deliver /spl sim/.5 MA, with a rise time of approximately 10 ns, to a load of about 5-10 /spl Omega/. Advantages of this configuration include low current jitter, power gain, low resistive voltage drop, and minimization of trigger input power as the result of using stages. First, plasma is introduced into the TPOS's A-K gap from plasma flash board sources. Current then flows through the plasma effectively shorting the A-K gap. Next, the switch is triggered when a pulse (50-150 ns rise time) is sent through a magnetic field coil. The energized coil gives rise to an axial magnetic field that pushes the plasma away from the cathode via the j/spl times/B force. (Clearly, this assumes that the magnetic field does not substantially penetrate the plasma, and that the plasma is azimuthally uniform.) Finally, the device triggers another similar stage in series with the first thus creating power amplification. The two stage design is novel, and this experiment is the first to implement magnetically triggered stages. In order for the switch to open correctly the plasma must travel sufficiently far away from the cathode. The plasma travels at the Alfven speed which is proportional to the magnetic field strength and inversely proportional to the density and mass of the plasma. Small percentages of water and oxygen exist, but the plasma is assumed to be dominantly composed of carbon. Therefore, since the mass and magnetic field are known, it is possible to infer the density by observing the opening speed. This is accomplished by measuring the plasmas location combined with the knowledge of the time dependent inductance and electron current. Specifically, if one assumes an axial field of /spl sim/1T, and an Alfven speed of approximately 1/spl times/10/sup 5/ to 1/spl times/10/sup 6/ m/s, this equates to a density of roughly 4/spl times/10/sup 21/ to 4/spl times/10/sup 19/ m/sup -3/. If the density is much higher, the switch may not open properly since the plasma's velocity is not sufficient to traverse the gap in the allotted time. Careful study of these characteristics is being carried out via side apparatus and magnetic field calculations. Hopefully, analysis leads to an ample characterization of the switch and ultimately a better understanding of the manner in which the two stages function.
Holographic laser scanners using generalized zone plates (1982)

Aberration properties in holographic zone plates for use in laser scanners are investigated. A generalized holographic zone plate is proposed. To generate the zone plate hologram, holographic optical product operations between plural coherent spherical waves, are applied. When spherical waves, N in number, are applied, aberration can be corrected in a scan length magnification equal to or less than N(2). Experimentally, a remarkable aberration correction effect for this hologram generation method is demonstrated for over 50-cm scan length. The configuration and features are described for the developed point-of-sale (POS) scanner employing generalized zone plate holograms.
Toward 3D-guided prostate biopsy target optimization: an estimation of tumor sampling probabilities (2014)

Magnetic resonance imaging (MRI)-targeted, 3D transrectal ultrasound (TRUS)-guided “fusion” prostate biopsy aims to reduce the ~23% false negative rate of clinical 2D TRUS-guided sextant biopsy. Although it has been reported to double the positive yield, MRI-targeted biopsy still yields false negatives. Therefore, we propose optimization of biopsy targeting to meet the clinician’s desired tumor sampling probability, optimizing needle targets within each tumor and accounting for uncertainties due to guidance system errors, image registration errors, and irregular tumor shapes. We obtained multiparametric MRI and 3D TRUS images from 49 patients. A radiologist and radiology resident contoured 81 suspicious regions, yielding 3D surfaces that were registered to 3D TRUS. We estimated the probability, P, of obtaining a tumor sample with a single biopsy. Given an RMS needle delivery error of 3.5 mm for a contemporary fusion biopsy system, P ≥ 95% for 21 out of 81 tumors when the point of optimal sampling probability was targeted. Therefore, more than one biopsy core must be taken from 74% of the tumors to achieve P ≥ 95% for a biopsy system with an error of 3.5 mm. Our experiments indicated that the effect of error along the needle axis on the percentage of core involvement (and thus the measured tumor burden) was mitigated by the 18 mm core length.
Field test of classical symmetric encryption with continuous variables quantum key distribution (2012)

We report on the design and performance of a point-to-point classical symmetric encryption link with fast key renewal provided by a Continuous Variable Quantum Key Distribution (CVQKD) system. Our system was operational and able to encrypt point-to-point communications during more than six months, from the end of July 2010 until the beginning of February 2011. This field test was the first demonstration of the reliability of a CVQKD system over a long period of time in a server room environment. This strengthens the potential of CVQKD for information technology security infrastructure deployments.
Infrared-visualized air turbulence (1990)

An IR-absorbing tracer gas when viewed against a warm background with an infrared short wave-band camera appropriately filtered can be used for detecting and recording the air turbulence caused by objects in laminar air streams in cleanroom environments. Air flow turbulence patterns in wind tunnels and from product prototypes have also been sucessfully recorded.
Identification of an Emergent Porcine Circovirus-2 in Vaccinated Pigs from a Brazilian Farm during a Postweaning Multisystemic Wasting Syndrome Outbreak (2014)

ABSTRACT Three porcine circovirus-2 strains were isolated from pigs on a Brazilian farm during an outbreak, indicating a vaccine failure. They present identical genomic sequences, with high identities to other isolates that were also related to vaccination failures, supporting the recent theory about an antigen drift being associated with vaccine failures throughout the world.
Aerosol scattering and absorption modulation transfer function (1993)

Recent experimental measurements of overall atmospheric modulation transfer function (MTF) indicate significant difference between the turbulence and overall atmospheric MTFs, except often at midday when turbulence is strong. We suggest here a physical explanation for those results which essentially relates to what we call a practical instrumentation-based atmospheric aerosol MTF which is a modification of the classical aerosol MTF theory. It is shown that system field-of-view and dynamic range affect strongly aerosol and overall atmospheric MTFs. It is often necessary to choose between MTF and SNR depending upon dynamic range requirements. Also, a new approach regarding aerosol absorption is presented. It is shown that aerosol-absorbed irradiance is spatial frequency dependent and enhances the degradation in image quality arising from received scattered light. This is most relevant for thermal imaging. An analytically corrected model for the aerosol MTF is presented which is relevant for imaging. An important conclusion is that the aerosol MTF is often the dominant part in the actual overall atmospheric MTF all across the optical spectral region.
An innovative deep space application of GPS technology for formation flying spacecraft (1996)

This paper describes the Autonomous Formation Flying Sensor (AFF) concept for extremely precise autonomous relative position and attitude determination for formations of satellites or spacecraft where real-time or near-real-time knowledge of relative position and attitude are required. Its technology is built around commercially available receivers widely used in Global Positioning System (GPS) ground applications and recently flight-tested in space. This sensor, however, does not actually require any observations of GPS satellite data for precise spacecraft-to-spacecraft position and attitude measurements. Thus, the AFF could be used in deep space or in Earth orbit, with or without GPS satellite data. Studies indicated that the AFF can provide a relative range measurement accuracy of 1 cm, along with a relative attitude measurement accuracy of 1 arcminute over formation distances of 1 m to 1300 km.
Chemistry of cephalosporin antibiotics. 28. Preparation and biological activity of 3-(substituted)vinyl cephalosporins (1975)

3-(Substituted)vinylcephem nuclei have been prepared by the reaction of 3-formylcephem derivatives with stabilized phosphoranes. Appropriate synthetic steps allowed preparation of a series of 3-ethoxycarbonylvinyl- and 3-carboxyvinylcephem derivatives bearing a variety of 7-acylamino functions. The phenoxyacetyl and thiopheneacetyl derivatives of the 3-cyanovinylcephem nucleus were also prepared. Although general gram-positive activity was comparable to cephalothin in many cases, against penicillin G resistant Staphylococcus aureus, the new cephalosporins were of low effectiveness. The 3-(substituted)vinyl cephalosporins had good activity against a number of gram-negative organisms. In some cases, this activity was excellent. The N-acetyl analogs had surprisingly good activity relative to N-acetyl-7-ACA. The phenylmalonoyl side-chain derivatives were shown to have an unusual antibacterial spectrum expansion (relative to previously known cephalosporins) to include activity against Serratia marcescens and Pseudomonas aeruginosa.
A Doubly Salient Doubly Excited Variable Reluctance Motor (1995)

A new variable reluctance motor is introduced to help solve the energy circulation problems which exist during commutation in conventional variable reluctance motors (VRM's). The new motor design enables the energy stored in the magnetic field to be retained and utilized within the motor, instead of being returned to the source. The operating principles of the motor and associated converters are presented. The analysis shows that by employing both short pitch and full pitch windings, this new motor can eliminate the two problems without extra conductors in the slots. As a result, the new motor has the following important performance advantages over conventional VRM's: (1) It allows a significant improvement in the turn-off process and therefore allows higher speed capacity; (2) it has higher output with the same or higher efficiency with the same output because of the improvement on the turn-off performance and due to the utilization of the trapped energy; (3) the machine can have a higher output with the same power converter because of the improvement of the energy conversion ratio.
Learning to recognize Abnormalities in Chest X-Rays with Location-Aware\n Dense Networks (2018)

Chest X-ray is the most common medical imaging exam used to assess multiple\npathologies. Automated algorithms and tools have the potential to support the\nreading workflow, improve efficiency, and reduce reading errors. With the\navailability of large scale data sets, several methods have been proposed to\nclassify pathologies on chest X-ray images. However, most methods report\nperformance based on random image based splitting, ignoring the high\nprobability of the same patient appearing in both training and test set. In\naddition, most methods fail to explicitly incorporate the spatial information\nof abnormalities or utilize the high resolution images. We propose a novel\napproach based on location aware Dense Networks (DNetLoc), whereby we\nincorporate both high-resolution image data and spatial information for\nabnormality classification. We evaluate our method on the largest data set\nreported in the community, containing a total of 86,876 patients and 297,541\nchest X-ray images. We achieve (i) the best average AUC score for published\ntraining and test splits on the single benchmarking data set (ChestX-Ray14),\nand (ii) improved AUC scores when the pathology location information is\nexplicitly used. To foster future research we demonstrate the limitations of\nthe current benchmarking setup and provide new reference patient-wise splits\nfor the used data sets. This could support consistent and meaningful\nbenchmarking of future methods on the largest publicly available data sets.\n
Evaluation of Frequency Domain Analysis of a Multiwavelength Photoacoustic Signal for Differentiating Malignant From Benign and Normal Prostates (2016)

Preliminary results of our ex vivo human prostate study suggest that spectral parameters obtained by performing frequency domain analysis of photoacoustic signals can be used to differentiate between malignant and nonmalignant prostate.
A gridded electron gun for a sheet beam klystron (2004)

This paper describes the development of an electron gun for a sheet beam klystron. Initially intended for accelerator applications, the gun can operate at a higher perveance than one with a cylindrically symmetric beam. Results of 2D and 3D simulations are discussed.
Measuring hearing-aid performance with complex signals. (1992)

New test procedures are being developed for hearing aids based on the response to complex test signals. The tests are motivated by the need to better describe the response of a hearing aid to a speechlike stimulus, since conventional measurements, such as pure-tone sweeps, are often inadequate in showing the behavior that will occur under conditions of actual use. The hearing-aid response typically includes both linear and nonlinear behavior, and both need to be described. Measurement techniques that will be discussed include the use of speech-shaped noise to measure frequency response, the use of bias tones to help determine the frequency response of a nonlinear device such as an automatic gain-control (AGC) circuit, the use of coherence to measure nonlinear distortion, and the use of recorded speech to measure the effects of adaptive signal-processing circuits.
The use of underwater hyperspectral imaging deployed on remotely operated vehicles - methods and applications (2016)

Currently a new underwater hyperspectral imager (UHI) have been deployed on Remotely Operated Vehicles (ROV) for a more automated identification, mapping and monitoring of bio-geo-chemical objects of interest (OOI). Sea floor maps based on UHI can be used to classify 001 based on specific optical fingerprints providing spectral upwelling radiance or reflectance with up to 1 nm spectral resolution in the visible range for each image pixel. Different habitats comprising soft bottom, deep and cold water coral reefs, sponge habitats, pipeline monitoring and kelp forest maps are examples for UHI-based mapping. Characterising material surface on man-made objects such as corrosion on pipelines and subsea structures and archaeological objects are other examples. The overall image quality and identification success of OOI can be optimized if movements of the ROV is controlled by a dynamic position (DP) system and corresponding speed, altitude, pitch, roll and yaw control. Likewise, illumination control is important to provide proper light intensity, spectral composition and illumination evenness of OOI to enhance data quality. The benefits of using UHI for seafloor habitat mapping can be evaluated by four categories of resolution. These are A) spatial resolution (image pixel size), B) spectral resolution (1-10 nm, 400-800 nm), C) radiometric resolution (dynamic range, bits per pixel), and D) temporal resolution for time-series and monitoring. These categories of resolution are discussed with respect to OOI identification and mapping using different case examples.
Coding for Scalable Blockchains via Dynamic Distributed Storage (2021)

Blockchains store transaction data in the form of a distributed ledger where each node in the network stores a current copy of the sequence of transactions as a hash chain. This requirement of storing the entire ledger incurs a high storage cost that grows undesirably large for high transaction rates and large networks. In this work we use secret key sharing, private key encryption, and distributed storage to design a coding scheme such that each node stores only a part of each transaction, thereby reducing the cold storage cost to a fraction of its original cost. In addition, the storage code ensures the security of the storage from active adversaries that may aim to corrupt prior transactions by altering copies of the ledger. We further employ a dynamic zone allocation algorithm that spreads the node allocation and data distribution across transactions. Under this coding scheme we show that we can also improve the integrity of the transaction data in the network over current schemes.
A Cyclic Ion Mobility-Mass Spectrometry System (2019)

Improvements in the performance and availability of commercial instrumentation have made ion mobility-mass spectrometry (IM-MS) an increasingly popular approach for the structural analysis of ionic species as well as for separation of complex mixtures. Here, a new research instrument is presented which enables complex experiments, extending the current scope of IM technology. The instrument is based on a Waters SYNAPT G2-S i IM-MS platform, with the IM separation region modified to accept a cyclic ion mobility (cIM) device. The cIM region consists of a 98 cm path length, closed-loop traveling wave (TW)-enabled IM separator positioned orthogonally to the main ion optical axis. A key part of this geometry and its flexibility is the interface between the ion optical axis and the cIM, where a planar array of electrodes provides control over the TW direction and subsequent ion motion. On either side of the array, there are ion guides used for injection, ejection, storage, and activation of ions. In addition to single and multipass separations around the cIM, providing selectable mobility resolution, the instrument design and control software enable a range of "multifunction" experiments such as mobility selection, activation, storage, IMS <sup>n</sup>, and importantly custom combinations of these functions. Here, the design and performance of the cIM-MS instrument is highlighted, with a mobility resolving power of approximately 750 demonstrated for 100 passes around the cIM device using a reverse sequence peptide pair. The multifunction capabilities are demonstrated through analysis of three isomeric pentasaccharide species and the small protein ubiquitin.
Customized Metabolomics Database for the Analysis of NMR <sup>1</sup>H–<sup>1</sup>H TOCSY and <sup>13</sup>C–<sup>1</sup>H HSQC-TOCSY Spectra of Complex Mixtures (2014)

A customized metabolomics NMR database, termed (1)H((13)C)-TOCCATA, is introduced, which contains complete (1)H and (13)C chemical shift information on individual spin systems and isomeric states of common metabolites. Since this information directly corresponds to cross sections of 2D (1)H-(1)H TOCSY and 2D (13)C-(1)H HSQC-TOCSY spectra, it allows the straightforward and unambiguous identification of metabolites of complex metabolic mixtures at (13)C natural abundance from these types of experiments. The (1)H((13)C)-TOCCATA database, which is complementary to the previously introduced TOCCATA database for the analysis of uniformly (13)C-labeled compounds, currently contains 455 metabolites, and it can be used through a publicly accessible web portal. We demonstrate its performance by applying it to 2D (1)H-(1)H TOCSY and 2D (13)C-(1)H HSQC-TOCSY spectra of a cell lysate from E. coli, which yields a substantial improvement over other databases, as well as 1D NMR-based approaches, in the number of compounds that can be correctly identified with high confidence.
Cultivated Corneal Endothelial Cell Sheet Transplantation in a Primate Model (2007)

A model of cultivated corneal endothelial transplantation for corneal endothelial dysfunction was established in primates whose corneal endothelial cells have less proliferative capacity in vivo. Our results suggest that this is a useful model for long-term observation in advance of the future clinical application of cultivated corneal endothelial transplantation.