gebhart/patrepeval huggingface dataset:
Double-Differential-Fed, Dual-Polarized Patch Antenna With 90 dB Interport RF Isolation for a 2.4 GHz In-Band Full-Duplex Transceiver (2017)

This letter presents a 2.4 GHz, dual-polarized microstrip patch antenna with extremely high interport isolation for a shared antenna architecture-based in-band full-duplex transceiver. The presented antenna configuration is based on four-ports linearly polarized single radiating element with differential feeding for both transmit (T <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</sub> ) and receive (R <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</sub> ) operation. The double-differential feeding using two identical 3 dB/180° ring hybrid couplers with nice amplitude and phase balance effectively suppresses the interport RF leakage to achieve very high isolation. The prototype of the proposed antenna architecture is implemented using a 1.6 mm thick general-purpose FR-4 substrate. The implemented antenna provides more than 90 and 80dB interport RF isolation for 20 and 40 MHz bandwidths, respectively, in addition to more than 98 dB port-to-port peak isolation when measured inside an anechoic chamber. To the best of our knowledge, this is the highest amount of RF isolation reported for a single dual-polarized patch antenna.
An automated segmentation method for three-dimensional carotid ultrasound images (2001)

We have developed an automated segmentation method for three-dimensional vascular ultrasound images. The method consists of two steps: an automated initial contour identification, followed by application of a geometrically deformable model (GDM). The formation of the initial contours requires the input of a single seed point by the user, and was shown to be insensitive to the placement of the seed within a structure. The GDM minimizes contour energy, providing a smoothed final result. It requires only three simple parameters, all with easily selectable values. The algorithm is fast, performing segmentation on a 336 x 352 x 200 volume in 25 s when running on a 100 MHz 9500 Power Macintosh prototype. The segmentation algorithm was tested on stenosed vessel phantoms with known geometry, and the segmentation of the cross-sectional areas was found to be within 3% of the true area. The algorithm was also applied to two sets of patient carotid images, one acquired with a mechanical scanner and the other with a freehand scanning system, with good results on both.
Quantum Cryptography for Secure Communications to Low-Earth Orbit Satellites (1999)

This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at Los Alamos National Laboratory (LANL). Quantum cryptography is an emerging technology in which two parties may simultaneously generate shared, secret cryptographic key material using the transmission of quantum states of light. The security of these transmissions is based on the inviolability of the laws of quantum mechanics. An adversary can neither successfully tap the quantum transmissions, nor evade detection. Key material is built up using the transmission of a single-photon per bit. We have developed an experimental quantum cryptography system based on the transmission of non-orthogonal single-photon polarization states to generate shared key material over line-of-sight optical links. Our results provide strong evidence that cryptographic key material could be generated on demand between a ground station and a satellite (or between two satellites), allowing a satellite to be securely re-keyed on in orbit.
Design of potent, cyclic peptide bradykinin receptor antagonists from conformationally constrained linear peptides (1993)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTDesign of potent, cyclic peptide bradykinin receptor antagonists from conformationally constrained linear peptidesSarvajit Chakravarty, Deidre Wilkins, and Donald J. KyleCite this: J. Med. Chem. 1993, 36, 17, 2569–2571Publication Date (Print):August 1, 1993Publication History Published online1 May 2002Published inissue 1 August 1993https://pubs.acs.org/doi/10.1021/jm00069a016https://doi.org/10.1021/jm00069a016research-articleACS PublicationsRequest reuse permissionsArticle Views135Altmetric-Citations28LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts
Critical assessment of operational path analysis: mathematical problems of transmissibility estimation (2008)

Classical transfer path analysis (TPA) is a widely used and reliable method for tackling noise and vibration problems. But due to its complexity and time-consuming measurement procedure there is an ongoing research for simpler and faster methods. One such method, most often referred to as operational path analysis (OPA), was presented two years ago and has quickly gained popularity in the NVH field for its speed and ease of use. To estimate path contributions transmissibilities are calculated from the measured operational reference and target accelerations and sound pressures. This new method is now critically examined and compared to a reliable classical TPA measurement. The results of this examination reveal three significant weaknesses. This paper focuses on the problems related to the estimation of transmissibilities which mostly arise from the limited amount of orders present in the signal and the coherence between inputs. It is shown that despite the advantages of the method, it is not applicable in many situations and has to be used with care for it can easily give misleading results.
Synthesis and Characterization of Environmentally Benign Nontoxic Pigments: RE2Mo2O9 (RE = La or Pr) (2005)

Abstract New inorganic pigments based on rare earth molybdenum mixed oxides: RE2Mo2O9 (RE = La or Pr) have been synthesized with a goal of preparing environmentally secure colorants. Characterizations using XRD, UV–vis spectroscopy, and CIE 1976 color coordinates assessment reveals the formation of compounds displaying colors: white for La2Mo2O9 and yellow-green for Pr2Mo2O9. The prepared pigments consisting of nontoxic elements and further found to be thermally and chemically stable.
Spatial misregistration in hyperspectral cameras: lab characterization and impact on data quality in real-world images (2020)

Hyperspectral cameras capture images where every pixel contains spectral information of the corresponding small area of the depicted scene. Spatial misregistration—differences in spatial sampling between different spectral channels—is one of the key quality parameters of these cameras, because it may have a large impact on the accuracy of the captured spectra. Spatial misregistration unifies various factors, such as differences in the position of the optical point spread function (PSF) in different spectral channels, differences in PSF size, and differences in PSF shape. Ideally, there should be no difference in spatial sampling across the spectral channels, but in any real camera, all these factors are present to some degree. Our work shows the magnitude of the spectral errors caused by these spatial misregistration factors of different magnitudes and in various combinations when acquiring hyperspectral images of real scenes. The spectral errors are calculated in Virtual Camera software where high-resolution airborne images of real-world scenes and several PSFs of different hyperspectral cameras are used as the input. The misregistration factors are simulated. Two different methods for quantifying spatial misregistration in the lab are also tested and compared using the correlation with the errors in the real-world scenes as the criterion. The results are used to suggest the best camera characterization approach that would adequately predict spatial misregistration errors and allow reliable comparison of different hyperspectral cameras to each other.
Integrated rare-Earth doped mode-locked lasers on a CMOS platform (2018)

Mode-locked lasers provide extremely low jitter optical pulse trains for a number of applications ranging from sampling of RF-signals and optical frequency combs to microwave and optical signal synthesis. Integrated versions have the advantage of high reliability, low cost and compact. Here, we describe a fully integrated mode-locked laser architecture on a CMOS platform that utilizes rare-earth doped gain media, double-chirped waveguide gratings for dispersion compensation and nonlinear Michelson Interferometers for generating an artificial saturable absorber to implement additive pulse mode locking on chip. First results of devices at 1.9 μm using thulium doped aluminum-oxide glass and operating in the Q-switched mode locking regime are presented.
Tailorable integrated optofluidic filters for biomolecular detection (2011)

Spectral filtering is an essential component of biophotonic methods such as fluorescence and Raman spectroscopy. Predominantly utilized in bulk microscopy, filters require efficient and selective transmission or removal of signals at one or more wavelength bands. However, towards highly sensitive and fully self-contained lab-on-chip systems, the integration of spectral filters is an essential step. In this work, a novel optofluidic solution is presented in which a liquid-core optical waveguide both transports sample analytes and acts as an efficient filter for advanced spectroscopy. To this end, the wavelength dependent nature of interference-based antiresonant reflecting optical waveguide technology is exploited. An extinction of 37 dB, a narrow rejection band of only 2.5 nm and a free spectral range of 76 nm using three specifically designed dielectric layers are demonstrated. These parameters result in an 18.4-fold increase in the signal-to-noise ratio for on-chip fluorescence detection. In addition, liquid-core waveguide filters with three operating wavelengths were designed for Förster resonance energy transfer detection and demonstrated using doubly labeled oligonucleotides. Incorporation of high-performance spectral processing illustrates the power of the optofluidic concept where fluidic channels also perform optical functions to create innovative and highly integrated lab-on-chip devices.
Ductile Fire-Resistive Material for Enhanced Fire Safety Under Multi-Hazards - A Feasibility Study (2014)

Multi-hazards, such as earthquake and/or impact followed by fire, represent major challenges for fire protection of steel structures. Spray-applied, fire-resistive material (SFRM) is one of the most widely used passive fire protection materials in North America. However, SFRM is inherently brittle and tends to dislodge or delaminate under extreme loading conditions (earthquakes or impacts) and even under normal service conditions such as wind-induced building movement. Such loss of fire protection material puts a steel structure in great danger under fire loading. As an alternative to conventional brittle cementitious materials, engineered cementitious composites (ECC) is a family of high-performance, fiber-reinforced, cementitious composites. ECC typically exhibits strain-hardening behavior with very high tensile ductility (3-5%) under static and high rate loading. In this paper, a new type of fire-resistive material that combines the desirable thermal insulation property of SFRM and the enhanced ductility of ECC is proposed as an alternative material to current SFRM. Two preliminary mixture designs are presented. The thermal conductivity of the new fire-resistive ECC is measured in accordance with ASTM E2584 and is shown to be similar or lower than a conventional SFRM within the same density range. The proposed material achieves tensile strength up to 3 MPa and tensile strain capacity as high as 2.9%, significantly higher than those of conventional SFRM. Fire-resistive ECC with enhanced mechanical performance is expected to improve the overall fire safety of steel structure under multi-hazards.
Nanofibrous Microfiltration Membrane Based on Cellulose Nanowhiskers (2011)

A multilayered nanofibrous microfiltration (MF) membrane system with high flux, low pressure drop, and high retention capability against both bacteria and bacteriophages (a virus model) was developed by impregnating ultrafine cellulose nanowhiskers (diameter about 5 nm) into an electrospun polyacrylonitrile (PAN) nanofibrous scaffold (fiber diameter about 150 nm) supported by a poly(ethylene terephthalate) (PET) nonwoven substrate (fiber diameter about 20 μm). The cellulose nanowhiskers were anchored on the PAN nanofiber surface, forming a cross-linked nanostructured mesh with very high surface-to-volume ratio and a negatively charged surface. The mean pore size and pore size distribution of this MF system could be adjusted by the loading of cellulose nanowhiskers, where the resulting membrane not only possessed good mechanical properties but also high surface charge density confirmed by the conductivity titration and zeta potential measurements. The results indicated that a test cellulose nanowhisker-based MF membrane exhibited 16 times higher adsorption capacity against a positively charged dye over a commercial nitrocellulose-based MF membrane. This experimental membrane also showed full retention capability against bacteria, for example, E. coli and B. diminuta (log reduction value (LRV) larger than 6) and decent retention against bacteriophage MS2 (LRV larger than 2).
Solid-Phase Synthesis of the Bicyclic Peptide OL-CTOP Containing Two Disulfide Bridges, and an Assessment of Its In Vivo μ-Opioid Receptor Antagonism after Nasal Administration (2023)

New strategies facilitate the design of cyclic peptides which can penetrate the brain. We have designed a bicyclic peptide, OL-CTOP, composed of the sequences of a selective μ-opioid receptor antagonist, CTOP (f-<i>cyclo</i>(CYwOTX)T) (X = penicillamine, Pen; O = ornithine) and odorranalectin, OL (YASPK-<i>cyclo</i>(CFRYPNGVLAC)T), optimized its solid-phase synthesis and demonstrated its ability for nose-to-brain delivery and in vivo activity. The differences in reactivity of Cys and Pen thiol groups protected with trityl and/or acetamidomethyl protecting groups toward I<sub>2</sub> in different solvents were exploited for selective disulfide bond formation on the solid phase. Both the single step and the sequential strategy applied to macrocyclization reactions generated the desired OL-CTOP, with the sequential strategy yielding a large quantity and better purity of crude OL-CTOP. Importantly, intranasally (i.n.s.) administered OL-CTOP dose-dependently antagonized the analgesic effect of morphine administered to mice through the intracerebroventricular route and prevented morphine-induced respiratory depression. In summary, the results demonstrate the feasibility of our solid-phase synthetic strategy for the preparation of the OL-CTOP bicyclic peptide containing two disulfide bonds and reveal the potential of odorranalectin for further modifications and the targeted delivery to the brain.
Optical Phased Array with Electromechanical Phase Shifters (2019)

We propose a chip-scale optical phased array (OPA) enabling steering along two orthogonal angles using integrated electromechanical optical phase shifters. Initial experimental results from fabricated silicon nitride OPAs are presented.
Evaluation of algorithms for segmentation of the prostate boundary from 3D ultrasound images (2004)

We evaluated three algorithms for prostate boundary segmentation from 3D ultrasound images. In the parallel segmentation method, the 3D image was sliced into parallel, contiguous 2D images, whereas in the rotational method, the image was sliced in a rotational manner. Using either method, four points were selected on a central slice and used to initiate a 2D deformable model. The segmented contour was propagated to adjacent slices until the entire prostate was segmented. In the volume-based method, the 3D image was segmented directly without slicing it. Each segmentation algorithm was applied to four 3D images, and the results were compared to manual segmentation. Average volume errors of -8.58%, -1.95% and -5.01% were estimated for the parallel, rotational and volume-based methods, respectively. Approximately 20% of the slices required editing in the parallel method, whereas 13% required editing in the rotational method. Although only one surface segmented using the volume-based method needed editing, manual editing was difficult in 3D. Segmentation times, including editing, ranged from 42 to 82 seconds for the parallel method, from 27 to 52 seconds for the rotational method, and up to 55 seconds for the volume-based method. Based on these results, we recommend the rotational segmentation method.
Unveiling the Biometric Potential of Finger-Based ECG Signals (2011)

The ECG signal has been shown to contain relevant information for human identification. Even though results validate the potential of these signals, data acquisition methods and apparatus explored so far compromise user acceptability, requiring the acquisition of ECG at the chest. In this paper, we propose a finger-based ECG biometric system, that uses signals collected at the fingers, through a minimally intrusive 1-lead ECG setup recurring to Ag/AgCl electrodes without gel as interface with the skin. The collected signal is significantly more noisy than the ECG acquired at the chest, motivating the application of feature extraction and signal processing techniques to the problem. Time domain ECG signal processing is performed, which comprises the usual steps of filtering, peak detection, heartbeat waveform segmentation, and amplitude normalization, plus an additional step of time normalization. Through a simple minimum distance criterion between the test patterns and the enrollment database, results have revealed this to be a promising technique for biometric applications.
<sup>1</sup>H Nuclear Magnetic Resonance Metabolomics Analysis Identifies Novel Urinary Biomarkers for Lung Function (2010)

Chronic obstructive pulmonary disease (COPD), characterized by chronic airflow limitation, is a serious public health concern. In this study, we used proton nuclear magnetic resonance ((1)H NMR) spectroscopy to identify and quantify metabolites associated with lung function in COPD. Plasma and urine were collected from 197 adults with COPD and from 195 without COPD. Samples were assayed using a 600 MHz NMR spectrometer, and the resulting spectra were analyzed against quantitative spirometric measures of lung function. After correcting for false discoveries and adjusting for covariates (sex, age, smoking) several spectral regions in urine were found to be significantly associated with baseline lung function. These regions correspond to the metabolites trigonelline, hippurate and formate. Concentrations of each metabolite, standardized to urinary creatinine, were associated with baseline lung function (minimum p-value = 0.0002 for trigonelline). No significant associations were found with plasma metabolites. Urinary hippurate and formate are often related to gut microflora. This could suggest that the microbiome varies between individuals with different lung function. Alternatively, the associated metabolites may reflect lifestyle differences affecting overall health. Our results will require replication and validation, but demonstrate the utility of NMR metabolomics as a screening tool for identifying novel biomarkers of pulmonary outcomes.
Measuring-while-drilling method and system having a digital motor control (1979)

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Studies on the Application of Liquid Aromatic Secondary Amines as Chain Extenders and Reactive Carriers for Other Amine or Hydroxyl-Containing Polyurethane Curatives (1986)

Aromatic amines generally react rapidly with aromatic isocyanates. This reaction can be slowed to a controllable rate through the use of secondary amines. This paper demonstrates the versatility of secondary diamines as curatives for toluene diisocyanate (TDI) and diphenyl methane diisocyanate (MDI) based prepolymers. Types of polyols included in the study are polyesters such as polyethylene adipate (PEA) and polycaprolactone (PCP) and polyethers such as poly(oxytetramethylene) glycol (PTMG) and poly(oxypropylene) glycol (PPG).
A self-tuning controller for high-performance scanning tunneling microscopy (2017)

The loop gain in feedback control system of a Scanning Tunneling Microscope (STM) is proportional to a quantum mechanical property of the STM tip and sample, known as the Local Barrier Height (LBH). Variations in LBH can negatively affect the stability of feedback loop and increase the risk of tip-sample crash. In this paper, we propose a method for online estimation of the LBH and accordingly tuning the gains of a proportional-integral (PI) controller. Experimental results confirm enhanced stability of the STM with the tuning algorithm in effect.
Singular spectrum analysis applied to ultrasonic imaging of brachytherapy seeds (2006)

Singular spectrum analysis (SSA) shows promise for reliably imaging radioactive seeds implanted in the prostate gland. Brachytherapy using small titanium-shelled radioactive seeds is proving to be a well-accepted means of treating prostate cancer. Unfortunately, implantation using needles inserted transperineally causes gland movement, and the resulting distortion may cause seed misplacement and dosimetry errors. If actual seed locations can be determined during the brachytherapy procedure, then dosimetry errors can be corrected immediately in the operating room. SSA utilizes pairs of eigenvalues derived from the autocorrelation matrix of envelope-detected radiofrequency echo signals to identify seed-specific signal repetitions. The power spectrum associated with a repetition signal is computed to derive a P-value indicative of the likelihood of the presence of a seed at the location of that repetitive signal. Simulations to assess performance as a function of different levels of white and speckle noise and the presence of signals at repetition periods not associated with seeds. Experiments in an ideal scattering environment were performed, using seeds implanted in beef. Results show an encouraging potential of SSA for seed detection and imaging, and illustrate the basic trade-off considerations for optimization of SSA for clinical applications. [Work supported by NIH Grant R01 CA098465.]
Modular MT with a learned bilingual dictionary (2002)

The MT system described in this paper combines hand-built analysis and generation components with automatically learned example-based transfer patterns. Up to now, the transfer component used a traditional bilingual dictionary to seed the transfer pattern learning process and to provide fallback translations at runtime. This paper describes an improvement to the system by which the bilingual dictionary used for these purposes is instead learned automatically from aligned bilingual corpora, making the system's transfer knowledge entirely derivable from corpora. We show that this system with a fully automated transfer process performs better than the system with a hand-crafted bilingual dictionary. More importantly, this has enabled us to create in less than one day a new language pair, French-Spanish, which, for a technical domain, surpasses the quality bar of the commercial system chosen for comparison.