gebhart/patrepeval huggingface dataset:
Processes for Large Scale Photonic Integrated Circuits (1989)

The Silicon integrated circuit (IC) industry had evolved during the last 35 years by introducing and refining several important Silicon based processes (such as I2L, NMOS, CMOS etc). A process is comprised of a set of processing steps (e.g. Photolithography (Plit), etching, implantation etc.) which are executed in a precise order and under rigidly controlled conditions. The individual devices differ only by the set of Plit masks that are being used on a particular wafer. Our goal here is to develop a process, in the same sense, for large scale photonic integrated circuits (PIC's). Some of the building elements are; a. lasers. b. optical amplifiers. c. grating filters. d. passive waveguides. e. waveguide branches and passive couplers. f. directional couplers g. optical switches. h. optical modulators. i. waveguide detectors.
Effects of alpha-ketoisocaproate on adrenocorticotropin-induced suppression of lymphocyte function in sheep. (1991)

Previous studies of the amino acid analogue, alpha-ketoisocaproate (KIC), indicate that it can stimulate lymphocyte blastogenesis and antibody responses of sheep. To determine whether KIC could overcome the effects of adrenocorticotropic hormone (ACTH)-induced lymphocyte suppression, 24 lambs were fed a control diet, a diet supplemented with 0.05% KIC, or a diet supplemented with 0.05% of the parent amino acid leucine. Immune status was monitored by determining lymphocyte blastogenic responsiveness to phytohemagglutinin-P (PHA), concanavalin A (conA), and pokeweed mitogen (PWM) and percentages of T-cell subsets in the blood, using monoclonal antibodies and a flow cytometer. Serum cortisol, insulin, and glucagon concentrations also were determined. After 60 days of consuming the respective diet, lambs were administered either saline solution or ACTH (100 IU) twice daily for 3 consecutive days. Administration of ACTH increased serum cortisol and insulin concentrations; however, no effects were seen for serum glucagon concentration. Compared with saline administration, ACTH administration significantly (P less than 0.05) suppressed mitogen-stimulated lymphocyte blastogenesis by approximately 50%, regardless of the mitogen used, and significantly (P less than 0.01) decreased the percentage of circulating T lymphocytes and decreased (P less than 0.01) the ratio of T4 to T8 cells. Lambs fed KIC had greater PHA- and conA-stimulated blastogenic responses and significantly (P less than 0.05) increased ratio of T4 to T8 cells in the blood, compared with lambs fed the leucine-supplemented diet or the control diet and given corresponding injections. These data indicate that ACTH decreased in vitro lymphocyte blastogenesis and altered the subset ratios of blood lymphocytes in sheep. These changes were partially prevented by feeding KIC.
Demonstration of high-performance 10.16 μm quantum cascade distributed feedback lasers fabricated without epitaxial regrowth (1999)

We present measurement results on high-power low threshold quantum cascade distributed feedback lasers emitting infrared radiation at 10.16 μm. A lateral current injection scheme allowed the use of a strongly coupled surface grating without metal coverage and epitaxial regrowth. Although this design resulted in a simplified processing, the fabrication of high performance devices was demonstrated. The laser emitted 230 mW of pulsed power at 85 K, and 80 mW at room temperature. Threshold current densities of 1.85 kA/cm2 at 85 K and 5.4 kA/cm2 at room temperature were observed. Since the spectrum showed single mode behavior for all temperatures and power levels of the operating range, this device will be ideal for optical sensor applications.
Coset coding to extend the lifetime of memory (2013)

Some recent memory technologies, including phase change memory (PCM), have lifetime reliabilities that are affected by write operations. We propose the use of coset coding to extend the lifetimes of these memories. The key idea of coset coding is that it performs a one-to-many mapping from each dataword to a coset of vectors, and having multiple possible vectors provides the flexibility to choose the vector to write that optimizes lifetime. Our technique, FlipMin, uses coset coding and, for each write, selects the vector that minimizes the number of bits that must flip. We also show how FlipMin can be synergistically combined with the ability to tolerate bit erasures. Thus, our techniques help to prevent bits from wearing out and can then tolerate those bits that do wear out.
Procedures for Tuning a Multiresonator Photonic Filter (2007)

Two procedures have been devised for tuning a photonic filter that comprises multiple whispering-gallery mode (WGM) disk resonators. As used here, tuning signifies locking the filter to a specific laser frequency and configuring the filter to obtain a desired high-order transfer function. The main problem in tuning such a filter is how to select the correct relative loading of the resonators to realize a prescribed filter function. The first of the two procedures solves this problem. As temperature gradients develop during operation, the spectra of individual resonators tend to drift, primarily because of the thermorefractive effect. Thus, there arises the additional problem of how to adjust the tuning during operation to maintain the desired transfer function. The second of the two procedures solves this problem. To implement the procedures, it is necessary to incorporate the resonators into an apparatus like that of Figure 1. In this apparatus, the spectrum of each resonator can be adjusted individually, via the electro-optical effect, by adjusting a bias voltage applied to that resonator. In addition, the positions of the coupling prisms and resonators can be adjusted to increase or reduce the gaps between them, thereby reducing or increasing, respectively, the optical coupling between them. The optical power (Pi) in resonator i is monitored by use of a tracking photodiode. Another tracking diode monitors the power reflected from the input terminal (Pr), and still others monitor the input power (Pin) and output power (Po). The readings of these photodiodes are used to guide the tuning adjustments described in this paper.
Successive Transmit Beamforming Algorithms for Multiple-Antenna OFDM Systems (2007)

In this paper, we focus on the design and evaluation of new transmit beamforming algorithms for the multiple-input single-output (MISO) orthogonal frequency division multiplexing (OFDM) systems. The OFDM technique is very effective in combating frequency selective fading since it converts the broadband channel into several parallel flat fading channels. However, to implement transmit beamforming, the channel state information on each individual subcarrier has to be conveyed from the receiver to transmitter. In order to reduce the channel feedback requirement in the OFDM system, we take the time and frequency domain correlations of the channel fading into consideration. Based on our successive beamforming (SBF) technique, we develop several classes of feedback algorithms for the OFDM systems. These new algorithms use the knowledge from the previous frame or neighboring subcarrier to aid the beamforming codebook design for the current subcarrier. Through numerical simulations, we demonstrate that the proposed SBF algorithms require very little channel feedback, yet they provide better performance than that of the other existing OFDM beamformers
Semirational Directed Evolution of Loop Regions in Aspergillus japonicus β-Fructofuranosidase for Improved Fructooligosaccharide Production (2015)

The Aspergillus japonicus β-fructofuranosidase catalyzes the industrially important biotransformation of sucrose to fructooligosaccharides. Operating at high substrate loading and temperatures between 50 and 60°C, the enzyme activity is negatively influenced by glucose product inhibition and thermal instability. To address these limitations, the solvent-exposed loop regions of the β-fructofuranosidase were engineered using a combined crystal structure- and evolutionary-guided approach. This semirational approach yielded a functionally enriched first-round library of 36 single-amino-acid-substitution variants with 58% retaining activity, and of these, 71% displayed improved activities compared to the parent. The substitutions yielding the five most improved variants subsequently were exhaustively combined and evaluated. A four-substitution combination variant was identified as the most improved and reduced the time to completion of an efficient industrial-like reaction by 22%. Characterization of the top five combination variants by isothermal denaturation assays indicated that these variants displayed improved thermostability, with the most thermostable variant displaying a 5.7°C increased melting temperature. The variants displayed uniquely altered, concentration-dependent substrate and product binding as determined by differential scanning fluorimetry. The altered catalytic activity was evidenced by increased specific activities of all five variants, with the most improved variant doubling that of the parent. Variant homology modeling and computational analyses were used to rationalize the effects of amino acid changes lacking direct interaction with substrates. Data indicated that targeting substitutions to loop regions resulted in improved enzyme thermostability, specific activity, and relief from product inhibition.
Thermochemical generation of CS for CO chemical lasers (1976)

The development of a thermochemical technique for generating large quantities of carbon monosulfide (CS) is reported. The CS is produced from the thermal dissociation of carbon disulfide (CS/sub 2/) in a cyanogen-oxygen-CS/sub 2/ combustor operating at 1 atm and temperatures in excess of 2500 K. The CS is extracted from the combustor through a Mach 4 supersonic nozzle. The supersonic flow stream was sampled and then analyzed with a quadrupole mass spectrometer, and the data were compared with the results of an equilibrium calculation. Ratios for CS/CS/sub 2/ greater than two were measured. Such ratios are sufficient to fuel a CO chemical laser directly with CS.
Joint Optimization of Transform Coefficients for Hierarchical B Picture Coding in H.264/AVC (2007)

Coding of video sequences using hierarchical B pictures in the joint scalable video model (JSVM) for the scalability amendment of H.264/AVC has the benefit of improved rate distortion efficiency relative to other known temporal decomposition structures, besides providing temporal scalability. In the operational encoder control of the JSVM, the inter-picture dependencies within a hierarchical B picture structure are considered using a heuristic, where pictures that are more frequently used for motion compensation are coded with higher fidelity compared to pictures that are less often used for motion compensation. In this paper, we describe an approach where the dependencies introduced by motion compensation are also considered when selecting transform coefficient values. Our experimental results using an H.264/AVC conforming encoder show bit rate reductions of up to 10% compared to the quantization method used by JSVM.
A versatile polyacrylamide gel electrophoresis based sulfotransferase assay (2010)

The versatility of the current method comes from the ability that SDS-PAGE can separate proteins and small molecules according to different parameters. While mobilities of proteins during SDS-PAGE are inversely related to their sizes, mobilities of small molecules are positively related to their charge/mass ratios. The predicted relative mobility of a product to PAPS is a good indicator of whether a sulfotransferase can be assayed with SDS-PAGE. Because phosphorylation is most similar to sulfation in chemistry, the method is likely to be applicable to kinases as well.
Reservoir Simulation of Hydrogen Sulfide Production During a Steam-Assisted-Gravity-Drainage Process by Use of a New Sulfur-Based Compositional Kinetic Model (2016)

Summary Steam injection is commonly used as a thermal enhanced-oil-recovery (EOR) method because of its efficiency for recovering hydrocarbons, especially from heavy-oil and bitumen reservoirs. Reservoir models simulating this process describe the thermal effect of the steam injection, but generally neglect the chemical reactions induced by the steam injection and occurring in the reservoir. In particular, these reactions can lead to the generation and production of the highly toxic and corrosive acid gas hydrogen sulfide (H2S). The overall objective of this paper is to quantitatively describe the chemical aquathermolysis reactions that occur in oil-sands reservoirs undergoing steam injections and to provide oil companies with a numerical model for reservoir simulators to forecast the H2S-production risks. For that purpose, a new sulfur-based compositional kinetic model has been developed to reproduce the aquathermolysis reactions in the context of reservoir modeling. It is derived from results gathered on an Athabasca oil sand from previous laboratory aquathermolysis experiments. In particular, the proposed reactions model accounts for the formation of H2S issued from sulfur-rich heavy oils or bitumen, and predicts the modification of the resulting oil saturate, aromatic, resin, and asphaltene (SARA) composition vs. time. One strength of this model is that it is easily calibrated against laboratory-scale experiments conducted on an oil-sand sample. Another strength is that its calibration is performed while respecting the constraints imposed by the experimental data and the theoretical principles. In addition, in this study no calibration was needed at reservoir scale against field-production data. In the paper, the model is first validated with laboratory-scale simulations. The thermokinetic modeling is then coupled with a 2D reservoir simulation of a generic steam-assisted gravity drainage (SAGD) process applied on a generic Athabasca oil-sand reservoir. This formulation allows investigating the H2S generation at reservoir scale and quantifying its production. The H2S- to bitumen-production ratio against time computed by the reservoir simulation is found to be consistent with production data from SAGD operations in Athabasca, endorsing the proposed methodology.
Performance of a high-frequency thermoacoustic refrigerator (2001)

A thermoacoustic refrigerator pumped at an acoustic frequency of 4.4 kHz has been investigated for optimal geometric configuration for heat pumping. The device consists of a piezoelectric driver with a random stack in a wave cylindrical resonator with air at 1 atm as the working fluid. The temperature difference between the heat exchangers, at each end of the stack, has been studied as a function of acoustic intensity, stack position, stack length, and stack surface area. Results show that with sound levels of 160 dB the C.O.P. can be optimized to be around 3. Such performance strongly depends on the stack length with a compromise between effective stack area and quality factor of the resonator. Results will also be presented on the efficiency of the driver as a function of load.
<title>High-density recording on phase-change optical disks</title> (1995)

Current status of high density recording on phase change optical disks is summarized. More than 4.1 Mbits/mm<SUP>2</SUP> density of direct overwriting on phase change disks was achieved using red (680 nm) high power (35mW) LDs, large NA (0.6) optics, thin (t0.6 mm) substrates, mark-edge recording with write compensation, and land-groove recording technologies.
Interoperability of Line Differential Protection (2021)

Line differential protection is used for a long time to protect overhead lines and cables in transmission and distribution systems. The basic principle of line differential protection is Kirchhoff's current law. Due to this principle line differential protection is strictly selective to clear faults on the protected line.To apply Kirchhoff's current law a line differential protection needs the currents from both ends of the protected line. The currents from the local end can be measured directly by means of current transformers, connected to the line differential protection device. The remote end currents however cannot be measured directly by the local line differential protection device. In general, the remote end currents are measured by a line differential protection device of same type and afterwards sent via communication link.Due to bandwidth restrictions of the communication link, differences in pre-processing of the measured values and other device specific implementations there is no interoperability of line differential protection. In general line differential protection requires both devices to be from the same manufacturer. Often the same device type or even the same firmware version is required. Today there is no interoperability for line differential protection. In case one substation gets an update of the line differential protection, the remote substation needs an update of the related line differential protection too.This paper describes an actual case how interoperability was achieved for line differential protection of different protection platforms of one manufacturer. The problems and limitations for this use case are explained in detail.In addition to this the paper suggests an implementation of line differential protection based on sampled measured values and GOOSE according to IEC61850 and IEC61869. With this approach, the communication interface between the line differential protection devices becomes interoperable. More flexible solutions are found to be possible. For instance, a line differential scheme might consist of only one line differential relay, receiving sampled measured values from a merging unit located at the remote end. The trip command for the remote end might be transferred back via GOOSE to the merging unit located at the remote end. For redundancy even two different line differential protection relays could be used feeding each other with the sampled measured values from the remote end.
High-quality AlN grown on Si(111) by gas-source molecular-beam epitaxy with ammonia (1999)

Hexagonal AlN layers were grown on Si(111) by gas-source molecular-beam epitaxy with ammonia. The transition between the (7×7) and (1×1) silicon surface reconstructions, at 1100 K, was used for in situ calibration of the substrate temperature. The initial deposition of Al, at 1130–1190 K, produced an effective nucleation layer for the growth of AlN. The Al layer also reduced islands of SiNx that might be formed due to background NH3 on the silicon surface prior to the onset of epitaxial growth. The transition to two-dimensional growth mode, under optimum conditions, was obtained after the initial AlN thickness of ∼7 nm.
A new broadband circularly polarized dielectric resonator antenna (2002)

Open dielectric resonators (DRs) have been increasingly studied as antenna elements in recent years. They offer advantages such as small size, mechanical simplicity, no conduction loss, easy coupling to most transmission lines, ability to obtain different radiation characteristics using different modes of the DR, etc. Further, desired impedance bandwidth (in the range of about 1%-20%) can be obtained by the suitable choice of DR shape and permittivity. Of various possible shapes, a rectangular shaped DR antenna (DRA) provides advantages over other shapes, such as cylindrical and spherical. It is known that three TE/sub 111/ modes (TE/sub 111//sup x/,TE/sub 111//sup y/ and TE/sub 111//sup z/) of a rectangular shaped DRA radiate like x, y and z directed magnetic dipoles respectively. Given the advantages of DRAs, a circularly polarized (CP) element may provide useful benefits over other existing designs. In this paper, we report the development of a new rectangular CP DRA with a single slot or probe feed. The circular polarization is obtained by the excitation of two nearly degenerate orthogonal magnetic dipole modes. Measured results show that the antenna has a low axial ratio (AR) over a wide frequency band and has a wide beamwidth. The antenna element is easy to design and construct, and the dimensional tolerances are not stringent. The slot fed antenna is also compatible with MIC's and MMIC's and should be therefore useful in high frequency applications. Theoretical development, design and experimental results on DRAs of various permittivities (/spl epsiv//sub r/=10.8, 20 and 40) with both slot and probe feed are presented.
Quantum optic techniques for diagnostics of a gradient magnetometer atom interferometer (2009)

In this article, we highlight some of the problems inherent in fielding an atom interferometer sensor, specifically an atom interferometer gradient magnetometer of the type recently proposed [Davis, J.P.; Narducci, F.A. J. Mod. Opt. 2008, 55, 3173–3185]. In particular, we focus on the problems created by stray magnetic fields. We review some of the quantum optic techniques to measure local magnetic fields for the purpose of nulling them. We also present our implementation of a technique to non-destructively measure the temperature of an atom cloud. We highlight our implementation of these techniques and present our measurements.
Benzimidazole Ribonucleosides: Design, Synthesis, and Antiviral Activity of Certain 2-(Alkylthio)- and 2-(Benzylthio)-5,6-dichloro-1-(.beta.-D-ribofuranosyl)benzimidazoles (1994)

Several 2-alkylthio- and 2-benzylthio derivatives of 5,6-dichloro-1-(beta-D-ribofuranosyl)benzimidazole (DRB) have been designed and synthesized from 5,6-dichloro-1-(beta-D-ribofuranosyl)-benzimidazole-2-thione. All compounds were evaluated for activity against human cytomegalovirus (HCMV) and/or herpes simplex virus type-1 (HSV-1). Three different cytotoxicity assays were used to determine if the compounds were toxic to uninfected cells. Most of the 2-alkylthio compounds were either inactive against HCMV and HSV-1 or were active only at concentrations at or near those which produced toxicity in uninfected cells. The best separation between activity against HCMV and cytotoxicity was observed with the 2-benzylthio analog 7. This prompted us to synthesize the substituted 2-benzylthio analogs 11-23 using a Topliss Tree approach. None of these compounds were more active than compound 7; most of the analogs were weakly active against both HCMV and HSV-1, but the activity was not separated from cytotoxicity. On the basis of both antiviral and cytotoxicity data, compound 7 was the best compound in the series. It was more active against HCMV than DRB (the 2-unsubstituted analog), acyclovir, and foscarnet, but it was less active than ganciclovir.
WEBCAP (2005)

A staggering number of multimedia applications are being introduced every day. Yet, the inordinate delays encountered in retrieving multimedia documents make it difficult to use the Web for real-time applications such as educational broadcasting, video conferencing, and multimedia streaming. The problem of delivering multimedia documents in time while placing the least demands on the client, network and server resources is a challenging optimization problem. The WEBCAP is ongoing project that explores applying capacity planning techniques to manage or tune the Web resources (client, network, server) for optimal or near optimal performance, subject to minimizing the retrieval cost while satisfying the real-time constraints and available resources. The WEBCAP project consists of four software modules: object extractor, object representer, object scheduler, and system tuner. The four modules are connected serially with 3 feedback-loops. In this paper, we focus on how to extract objects from multimedia document and how to represent them as object and operation flow graphs while maintaining precedence relations among the objects.