gebhart/patrepeval huggingface dataset:
A new photodiode readout scheme for high resolution scintillation crystal arrays (2002)

We are exploring the possibility of using PIN photodiodes to readout the scintillation crystals used in positron emission tomography (PET) detector designs. Solid state photodetectors typically have a lower signal to noise ratio than photomultiplier tubes (PMTs). However, they have the advantage of compactness, and, thus, scintillation crystal readout schemes not available to PMTs because of their size and geometry limitations, are readily available to photodiodes. With current PET detector designs, only a small fraction of the available scintillation light created from 511 keV gamma ray interactions within the crystal is collected. Scintillation light collection studies were performed for several crystal geometries and surface treatments using both simulations and measurements. In this report, we present a feasible photodiode readout scheme that allows greater than 90% of the available scintillation light created in either BGO or LSO scintillation crystals to be collected by the photodetector. This improvement in light collection with the photodiode readout somewhat compensates for its lower inherent signal to noise ratios and makes it feasible for use in PET. In addition, a coincident timing spectrum resolution of 3.5 ns FWHM was measured using small crystals of LSO, one coupled to a photodiode, the other to a PMT.
Abstract MP12: The AA2-Ratio: A Novel Screening Test for Primary Aldosteronism in Hypertensive Patients (2015)

Primary aldosteronism (PA) is severe form of hypertension characterized by a strongly increased aldosterone secretion mediated by adenomas or other forms of adrenal hyper-activity. Once detected, PA can be usually cured by either surgical intervention or by appropriate pharmacologic treatments. This is also reflected in clinical guidelines of Endocrine Societies in Europe and the US, suggesting extensive PA screening activities among resistant hypertensive patients. The incidence of PA among hypertensive patients varies strongly between different studies, which is in part caused by the complex state-of-the-art testing procedure that unfortunately is far away from being a versatile PA screening tool. Despite strong limitations regarding selectivity, sensitivity and the interference with multiple anti-hypertensive drugs, the aldosterone-renin-ratio (ARR) is widely used for PA case detection. However, there is still a strong demand for accurate and reliable and patient friendly PA case detection. The use of novel and more accurate technologies for quantification of aldosterone and renin activity might help to improve the power of the ARR as a diagnostic tool for PA. However, there is a big need for a versatile PA screening assay that doesn’t interfere with anti-hypertensive treatments and therefore allows the clear identification of PA patients without complex corrections and adaptions being necessary and without increasing the patient’s cardiovascular risk in the course of the diagnostic process. The Aldosterone-to-Angiotensin-II-Ratio (AA2-Ratio) is a novel mass-spectrometry based high-throughput test for PA that combines the plasma levels of aldosterone and physiologically active angiotensin II into a diagnostic ratio. The test performance is superior to the ARR in terms of the diagnostic window and method accuracy. The AA2-Ratio does not interfere with standard anti-hypertensive drugs including ACE inhibitors. First data obtained in a proof-of-concept study investigating PA positive and negative patients proved the AA2-Ratio to be a powerful and cost-effective diagnostic tool for the diagnosis of PA in clinical practice.
Segmented channel routing (1990)

Routing channels in a field-programmable gate array contain predefined wiring segments of various lengths. These may be connected to the pins of the gates or joined end-to-end to form longer segments by programmable switches. The segmented channel routing problem is formulated, and polynomial time algorithms are given for certain special cases. The general problem is NP-complete, but it can be adequately solved in practice. Experiments indicate that a segmented channel with judiciously chosen segment lengths may near the efficiency of a conventional channel.
Clipping and Filtering-Based PAPR Reduction Method for Precoded OFDM-MIMO Signals (2010)

This paper presents a new peak-to-average power ratio (PAPR) reduction method based on clipping and filtering for precoded orthogonal frequency division multiplexing (OFDM)-multiple-input multiple-output (MIMO) transmission. While the conventional clipping and filtering method adds roughly the same interference power to each of the transmission streams, the proposed method restricts the interference power applied to the streams that experience good channel conditions. Since the sum capacity is dominated by the capacity of the streams that experience good channel conditions and the interference caused by the PAPR reduction process severely degrades the achievable capacity of these streams, the proposed method can significantly improve the achievable sum capacity compared to the conventional clipping and filtering method for a given PAPR. Simulation results demonstrate the capacity gain when using the proposed method compared to that when using the conventional method.
Energy-efficient floating-point arithmetic for software-defined radio architectures (2011)

The lack of hardware support for floating-point arithmetic in low-power software-defined radio architectures can significantly increase their software design time due to a time-consuming process of converting floating-point code to fixed-point code. Moreover, emerging wireless communication protocols involve several matrix based algorithms that are extremely sensitive to round-off errors in computations. Using fixed-point arithmetic for these algorithms can significantly impact the accuracy of algorithm results and may incur additional energy overhead due to the extra instructions required for fixed-point arithmetic. In this paper, we demonstrate that supporting floating-point arithmetic in hardware can deliver nearly 30% higher performance and energy efficiency than supporting only fixed-point arithmetic for key kernels of modern wireless communication protocols. The improvements can be further enhanced by our proposed high-throughput floating-point fused-multiply-add unit. Applying our proposed fused-multiply-add unit to key kernels improves performance of the baseline floating-point unit by as much as 60%, while reducing energy consumption by 30% and area by 33%. Although our approach may cause execution stalls depending on data, we show the performance impact of these stalls is negligible. We also employ dynamic range-based dynamic voltage and frequency scaling to further reduce the energy consumption of the processor by 25% for the same worst-case performance as the baseline floating-point implementation.
Solvent free synthesis of carboxylate–alumoxane nanoparticles using mechanical shear (2004)

Carboxylate-substituted alumina nanoparticles are produced solvent free using a Rheomixer. The general nature of this method has been demonstrated for L-lysine-, stearate-, and p-hydroxybenzoate-derived materials. The reaction rate and particle size are controlled by a combination of temperature and shear rate. The nanoparticles are spectroscopically equivalent to those reported from aqueous syntheses, however, the average particle size can be decreased and the particle size distribution narrowed depending on the reaction conditions.
Active attentional sampling for speed-up of background subtraction (2012)

In this paper, we present an active sampling method to speed up conventional pixel-wise background subtraction algorithms. The proposed active sampling strategy is designed to focus on attentional region such as foreground regions. The attentional region is estimated by detection results of previous frame in a recursive probabilistic way. For the estimation of the attentional region, we propose a foreground probability map based on temporal, spatial, and frequency properties of foregrounds. By using this foreground probability map, active attentional sampling scheme is developed to make a minimal sampling mask covering almost foregrounds. The effectiveness of the proposed active sampling method is shown through various experiments. The proposed masking method successfully speeds up pixel-wise background subtraction methods approximately 6.6 times without deteriorating detection performance. Also realtime detection with Full HD video is successfully achieved through various conventional background subtraction algorithms.
A high-brightness accelerator-based EUV source for metrology applications (2018)

One of the challenges of actinic metrology tools for EUV lithography is the availability of light sources with high brightness, stability, and availability. In particular, actinic patterned mask inspection on EUV reticles is considered an essential tool for the EUV lithography ecosystem and it requires an EUV source of high brightness. We present the design of a compact and accelerator-based light source producing EUV radiation with high-brightness for actinic metrology applications in the semiconductor industry. Our design is based on the well-established components and design principles. The specifications required for actinic mask inspection is achieved using a short period undulator and 430 MeV electron energy. The concentric design of storage and booster rings enables stable operation with a relatively small footprint. This study shows the commercial viability of a compact and high-brightness EUV source with high stability and reliability and demonstrates its feasibility for actinic metrology applications.
An Algorithm for Estimating Acceleration Magnitude and Impact Location Using Multiple Nonorthogonal Single-Axis Accelerometers (2004)

Accelerations of the head are the likely cause of concussion injury, but identifying the specific etiology of concussion has been difficult due to the lack of a valid animal or computer model. Contact sports, in which concussions are a rising health care concern, offer a unique research laboratory environment. However, measuring head acceleration in the field has many challenges including the need for large population sampling because of the relatively low incidence of concussions. We report a novel approach for calculating linear acceleration that can be incorporated into a head-mounted system for on-field use during contact sports. The advantages of this approach include the use of single-axis linear accelerometers, which reduce costs, and a nonorthogonal arrangement of the accelerometers, which simplifies the design criteria for a head-mounted and helmet compatible system. The purpose of this study was to describe the algorithm and evaluate its accuracy for measuring linear acceleration magnitude and impact location using computer simulation and experimental tests with various accelerometer configurations. A 10% error in magnitude and a 10 deg error in impact location were achieved using as few as six single-axis accelerometers mounted on a hemispherical headform.
3D imaging of surfaces and cells by numerical reconstruction of wavefronts in digital holography applied to transmission and reflection microscopy (2003)

We report on a numerical method for the reconstruction of wavefronts in digital holographic microscopy (DHM). It yields simultaneous amplitude and quantitative phase contrast imaging by acquiring a single hologram. The reconstruction method computes the propagation of the complex optical wavefront diffracted by the object and is used to determine the refractive index and/or shape of the object with accuracies in the nanometer range along the optical axis. The technique comprises the recording of a digital hologram of the specimen by means of a standard CCD camera at the exit of a Mach-Zehnder or Michelson type interferometer and an adjustment procedure to determine precisely the reconstruction parameters. The quantitative nature of the reconstructed phase distribution has been demonstrated by an application to surface profilometry where step height differences of a few nanometers have been measured. Another application takes place in biology for transmission phase-contrast imaging of living cells in culture with resolution reaching 30 nanometers in height.
Impedance element and band rejection filter using the same (1981)

Views Icon Views Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Icon Share Twitter Facebook Reddit LinkedIn Tools Icon Tools Reprints and Permissions Cite Icon Cite Search Site Citation Yahei Koyamada, Fujio Ishihara; Impedance element and band rejection filter using the same. J. Acoust. Soc. Am. 1 February 1981; 69 (2): 619. https://doi.org/10.1121/1.385429 Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentAcoustical Society of AmericaThe Journal of the Acoustical Society of America Search Advanced Search |Citation Search
Implementation of a new scanning method for high-resolution fluorescence tomography using thermo-sensitive fluorescent agents (2015)

Conventional fluorescence tomography provides images of the distribution of fluorescent agents within highly scattering media, but suffers from poor spatial resolution. Previously, we introduced a new method termed "temperature-modulated fluorescence tomography" (TM-FT) that generates fluorescence images with high spatial resolution. TM-FT first uses focused ultrasound to locate the distribution of temperature-sensitive fluorescence probes. Afterward, this a priori information is utilized to improve the performance of the inverse solver for conventional fluorescence tomography and reveal quantitatively accurate fluorophore concentration maps. However, the disadvantage of this novel method is the long data acquisition time as the ultrasound beam was scanned in a step-and-shoot mode. In this Letter, we present a new, fast scanning method that reduces the imaging time 40 fold. By continuously scanning the ultrasound beam over a 50 mm by 25 mm field-of-view, high-resolution fluorescence images are obtained in less than 29 min, which is critical for in vivo small animal imaging.
Engineered SERS Substrates with Multiscale Signal Enhancement: Nanoparticle Cluster Arrays (2009)

Defined nanoparticle cluster arrays (NCAs) with total lateral dimensions of up to 25.4 microm x 25.4 microm have been fabricated on top of a 10 nm thin gold film using template-guided self-assembly. This approach provides precise control of the structural parameters in the arrays, allowing a systematic variation of the average number of nanoparticles in the clusters (n) and the edge-to-edge separation (Lambda) between 1 < n < 20 and 50 nm < or = Lambda < or = 1000 nm, respectively. Investigations of the Rayleigh scattering spectra and surface-enhanced Raman scattering (SERS) signal intensities as a function of n and Lambda reveal direct near-field coupling between the particles within individual clusters, whose strength increases with the cluster size (n) until it saturates at around n = 4. Our analysis shows that strong near-field interactions between individual clusters significantly affect the SERS signal enhancement for edge-to-edge separations Lambda < 200 nm. The observed dependencies of the Raman signals on n and Lambda indicate that NCAs support a multiscale signal enhancement which originates from simultaneous inter- and intracluster coupling and |E|-field enhancement. The NCAs provide strong and reproducible SERS signals not only from small molecules but also from whole bacterial cells, which enabled a rapid spectral discrimination between three tested bacteria species: Escherichia coli, Bacillus cereus, and Staphylococcus aureus.
Rendering Deformable Surface Reflectance Fields (2004)

Animation of photorealistic computer graphics models is an important goal for many applications. Image-based modeling has emerged as a promising approach to capture and visualize real-world objects. Animating image-based models, however, is still a largely unsolved problem. In this paper, we extend a popular image-based representation called surface reflectance field to animate and render deformable real-world objects under arbitrary illumination. Deforming the surface reflectance field is achieved by modifying the underlying impostor geometry. We augment the impostor by a local parameterization that allows the correct evaluation of acquired reflectance images, preserving the original light model on the deformed surface. We present a deferred shading scheme to handle the increased amount of data involved in shading the deformable surface reflectance field. We show animations of various objects that were acquired with 3D photography.
Thermal Treatment of Crude Algae Oils Prepared Under Hydrothermal Extraction Conditions (2012)

We demonstrate that removal of oxygen and metals from crude algae oils produced by hydrothermal treatment processes is possible by thermal means alone and without the use of catalysts or hydrogen. Thermal treatment can reduce the total amounts of acids in the crude algae oil and thus decrease the total acidity of the oil. Thermal treatment also reduces the boiling point range of crude algae oils, making them more volatile and less viscous, benefitting shipping and upgrading. Trace metals are significantly reduced as the thermal treatment temperature increases. The results obtained in this study are consistent with existing theories of the formation of petroleum crude oils and create a link between the upgrading of crude algae oils and the mechanisms involved in the formation of conventional fossil fuels. The results and possible pathways of the reaction mechanisms are presented.
Performance of high‐power III‐nitride light emitting diodes (2008)

Abstract The performance of III‐nitride based high‐power light emitting diodes (LEDs) is reviewed. Direct color high‐power LEDs with 1 × 1 mm 2 chip size in commercial LUXEON ® Rebel packages are shown to exhibit external quantum efficiencies at a drive current of 350 mA ranging from ∼60% at a peak wavelength of ∼420 nm to ∼27% at ∼525 nm. The short wavelength blue LED emits ∼615 mW at 350 mA and >2 W at 1.5 A. The green LED emits ∼110 lm at 350 mA and ∼270 lm at 1.5 A. Phosphor‐conversion white LEDs (1 × 1 mm 2 chip size) are demonstrated that emit ∼126 lm of white light when driven at 350 mA and 381 lm when driven at 1.5 A (Correlated Color Temperature, CCT ∼ 4700 K). In a similar LED that employs a double heterostructure (DH) insign instead of a multi‐quantum well (MQW) active region, the luminous flux increases to 435 lm (CCT ∼ 5000 K) at 1.5 A drive current. Also discussed are experimental techniques that enable the separation of internal quantum efficiency and extraction efficiency. One technique derives the internal quantum efficiency from temperature and excitation‐dependent photoluminescence measurements. A second technique relies on variable‐temperature electroluminescence measurements and enables the estimation of the extraction efficiency. Both techniques are shown to yield consistent results and indicate that the internal quantum efficiency of short wavelength blue ( λ ∼ 420 nm) high‐power LEDs is as high as 71% even at a drive current of 350 mA. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Cancer immunotherapy by intratumoral injection of α-gal glycolipids. (2012)

Intratumoral injection of α-gal glycolipids is feasible and safe for inducing a protective anti-tumor immune response.
Molecular Addition Compounds. 10. Borane Adducts with <i>N</i>,<i>N</i>-Dialkylanilines for Hydroboration (1998)

Borane adducts with selected N,N-dialkylanilines have been prepared and examined as hydroborating agents. The adduct H3B:NPhPri2 is a solid, considered less desirable than liquid adducts as hydroborating agents. Fortunately, the adducts H3B:NPhBuiMe, H3B:NPhPriMe, H3B:NPhPriEt, and H3B:NPhPriPrn are liquids above 0 °C, hydroborating 1-octene in tetrahydrofuran in less than 1 h at room temperature. Convenient procedures are described for generating gaseous diborane quantitatively, either by thermal dissociation of the borane−N,N-diisopropylaniline adduct or by the reaction of a 2.00 M solution of sodium borohydride in triglyme with a 5.40 M solution of boron trifluoride in triglyme.
3D photonic structure for plug-and-play fiber to waveguide coupling (2018)

We show a 3D photonic structure for passive high alignment tolerance fiber to waveguide coupling. We measured a coupling efficiency of 2.5dB+/−0.4dB from fiber to a polymeric waveguide for fiber misalignments within a 17µm diameter.
Digital Memory Characteristics of Aromatic Polyimides Based on Pyridine and Its Derivatives (2018)

Soluble aromatic polyimides and polyvinyls were prepared by incorporating pyridine moiety and its derivatives in the backbone and the side groups, respectively: 6F-Py-<i>i</i> polymers based on the polyimide backbone (6F-Py-1 to 6F-Py-7) and PVPy-<i>i</i> polymers based on the polyvinyl backbone (PVPy-1 to PVPy-4). All polymers were found to be amorphous. The 6F-Py-<i>i</i> polymers were thermally stable up to 511-545 °C; the PVPy-<i>i</i> polymers were stable up to 362-376 °C. Their glass transitions, thin film densities, molecular orbitals, and band gaps were determined. The electrical devices fabricated with the polymers in an electrode/polymer/electrode structure revealed p-type unipolar write-once-read-many times (namely, permanent) or dynamic random access memory or dielectric behavior, depending on the substituents of the pyridine unit and the film thicknesses. In particular, such digital memory characteristics were found to originate from the pyridine moieties possessing a high charge affinity in the polymers. However, the pyridine moieties were found to still need at least two or more aromatic substituents to get enough power to stabilize charges via utilizing the resonance effects provided by the substituents. Overall, this study demonstrated that the pyridine unit conjugated with two or more aromatic substituents is a very useful component to design and synthesize digital memory materials based on thermally stable polyimides and other high performance polymers. The 6F-Py-<i>i</i> polymers have potential for the low-cost mass production of high-performance programmable unipolar permanent memory devices with very low power consumption.
A fast dynamic range compression with local contrast preservation algorithm for low dynamic range image enhancement (2012)

This paper presents a new fast dynamic range compression format with a local-contrast-preservation (FDRCLCP) algorithm to efficiently resolve low dynamic range (LDR) image enhancement problem for natural color images. The proposed FDRCLCP algorithm can combine with any continuously differentiable intensity transfer function to achieve LDR image enhancement. In combination with the FDRCLCP algorithm, a new intensity-transfer function that achieves satisfactory dynamic-range compression while preventing over enhancement in dark regions of the image is proposed. Experimental results validate that the proposed method provides better visual representation in comparison with two existing methods.
From del.icio.us to x.qui.site (2008)

We present X.QUI.SITE, a scalable system for managing recommendations for social tagging sites like del.icio.us. seamlessly incorporates various user behaviors into the recommendations and aims to recommend not only items of interest, but also other relevant information like interesting people and/or topics. Explanations are also provided so that users can obtain a better understanding of the recommendations and decide which recommendations to pursue further. We discuss the technical challenges involved in characterizing different user behaviors and in efficiently computing recommendation explanations.