gebhart/patrepeval huggingface dataset:
Scattering loss characteristics of selenide-based chalcogenide glass optical fibers (1992)

Scattering loss characteristics of Ge-Se binary chalcogenide glass optical fibers are investigated. It is found that there is a strong correlation between the wavelength-independent scattering loss and the absorption caused by H2O impurities. Therefore, the amount of H2O impurity mainly determines the wavelength-independent loss of these optical fibers. After removing the H2O impurity and adjusting the fabrication conditions, the transmission loss is less than 1 dB/m over a wide infrared wavelength region of 2–8.5 μm, except for a small peak at 4.5 μm.
Production of solar-grade silicon from purified metallurgical silicon (1976)

The long-term goal of this work is to produce silicon of solar-grade quality at 3 x 10 to the 6th kg/y for less than $10/kg by, or before 1986. The approach is to improve and expand upon the technology used today to commercially produce metallurgical-grade silicon (MG-Si). This is currently being accomplished by using purer raw materials in the arc furnace process for producing MG-Si, by upgrading the furnace itself, and by unidirectionally solidifying the molten silicon exiting the furnace. Solar cells fabricated from partially purified MG-Si have shown average AM0 efficiencies in the range of 9-11%. Since further MG-Si purification yet remains possible, fabrication of cells of considerably higher conversion efficiency is deemed feasible.
Transport and Retention of Aqueous Dispersions of Paramagnetic Nanoparticles in Reservoir Rocks (2010)

Abstract Paramagnetic nanoparticles have potential applications for enhanced oil recovery (by imposing an external field to control the behavior of injected fluids) and especially for evaluating oil saturations and other properties of an EOR target formation (by imposing a magnetic field near the wellbore after injecting fluid and measuring the response). However, the first requirement for these applications is the ability to place the particles a desired distance from the injection well. This means the particles should exhibit little retention in sedimentary rock and minimal formation damage. The ability to predict and control the degree of retention will be valuable for designing field trials and applications of such particles. We evaluate the transport of surface-treated paramagnetic iron-oxide nanoparticles in sedimentary rocks by injecting aqueous dispersions of the particles into core plugs of different lithologies. The nanoparticle loading ranges from concentrated (10 wt %) to dilute (0.1 wt %). The dispersions are prepared with a range of ionic strengths and pH. Several different surface treatments yield stable dispersions of these particles, but provide very different transport characteristics. Effluent concentration histories are measured for particles that undergo little retention. The results are interpreted in terms of surface charges, zeta potential, and van der Waals interaction between particles and rock. Our experiments indicate paramagnetic nanoparticles stabilized with small negatively-charged citrate ligands can significantly reduce retention in sedimentary rocks and incur little reduction in permeability. Little retention (&lt;5 % of particles injected over several pore volumes) can be achieved even at very large injected concentration (10 wt %). Citrate-stabilized dispersions were stable even at high salinity (3 wt% NaCl) and the citrate provided electrostatic repulsion between particles and the negatively-charged sandstone and carbonate lithologies tested here. On the other hand polyvinylpyrrolidone (PVP), tetramethylammonium hydroxide (TMAOH) and oleic acid bilayer coatings also stabilized particle dispersions, but the attraction between polymer and rock surface led to high or near-total retention of injected particles.
Towards an optimal beamforming algorithm for physical layer multicasting (2011)

The increasing popularity of applications involving group communications in wireless networks has led to the need for efficient multicasting solutions. The ability of smart antennas to beamform and hence improve the signal quality at the clients has made them especially attractive for multicasting applications. Unfortunately, the problem of multicast beamforming design is a non-convex optimization problem for which only suboptimal solutions has been proposed in the literature. In this work, we uncover a hidden convexity of the problem under certain channel conditions which happens frequently for practical systems with Rayleigh fading channel model. We propose a solution based on this observation which consists of two steps: (1) we solve the dual problem and check for a uniqueness condition; if satisfied, we show that the duality gap is zero and the solution of the primal problem is obtained based on the solution of the dual problem; (2) if the uniqueness condition is not satisfied, we use a gradient descent based approach. Our evaluations reveal that the proposed algorithm significantly improves the multicast performance over state-of-the-art solutions. Simulation results show that in most scenarios of interest the algorithm converges within a required limit in the first step with high probability. We also obtain the performance bounds for the primal problem based on the dual formulation.
New paradigm in IC package interconnections by reworkable nano-interconnects (2004)

We propose new IC packaging technologies that have the potential to bring about disruptive innovations in interconnect pitch, best electrical and mechanical properties, low-cost and chip size. Current approaches for chip to package interconnections are limited in terms of either pitch or electrical-mechanical trade-off properties. For example, lead free solder interconnects fail mechanically as the pitch is brought down from current 200 micron pitch to 20 micron. Compliant leads, on the other hand, solve mechanical reliability but at the expense of electrical performance. Solution-derived materials for reworkable nano-interconnects can be a viable technology to meet these two challenges. Nano-grained electroplated copper is chosen as the primary interconnect material. Compliancy was addressed by tuning the process to electroplate high-aspect-ratio structures. Reworkability was addressed by a thin, liquid lead-free solder interface between the interconnect and the package. Two approaches, sol-gel and electroless plating were used in this work to deposit these liquid interface films of lead free solders of the order of 50-300 nm. In the sol-gel process, metal-organic polymer solutions were heat-treated in a reducing atmosphere at 300/spl deg/C to form lead-free solders (Sn-Ag-Cu). In the other approach, lead-free alloy films were deposited from aqueous plating solutions consisting of suitable metal salts and reducing agents. This process was done at temperatures of 45/spl deg/C. The lead-free solder composition was controlled by altering the plating bath formulation. Lead-free solder films formed from both the above approaches were demonstrated to bond copper pads. Solution-derived nano-solder technology is an attractive low-cost method for bump-less nano-interconnects and other applications such as MEMS hermetic packaging and compliant interconnect bonding.
A two moments RC delay metric for performance optimization (2001)

For performance optimization tasks such as floorplanning, placement, buffer insertion, wire sizing, and global routing, the Elmore RC delay metric [3] remains popular due to its simple closed form expression, fast computation speed, and fidelity with respect to simulation. More accurate delay computation methods are typically either CPU intensive or difficult to implement. To bridge this gap between accuracy and simplicity, we propose the D2M RC delay metric, which is virtually as simple and fast as the Elmore metric but is bounded above by the Elmore delay, yet it rarely is more than a few percent below the actual delay. Consequently, the metric behaves like the Elmore metric in that it generally overestimates delay, but with consistently less error. Further, the metric is extremely accurate at the far end of RC lines.
The Development and Application of a Novel Safety-Catch Linker for BOC-Based Assembly of Libraries of Cyclic Peptides<sup>,</sup><sup>1</sup> (2001)

Cyclic peptides are appealing targets in the drug-discovery process. Unfortunately, there currently exist no robust solid-phase strategies that allow the synthesis of large arrays of discrete cyclic peptides. Existing strategies are complicated, when synthesizing large libraries, by the extensive workup that is required to extract the cyclic product from the deprotection/cleavage mixture. To overcome this, we have developed a new safety-catch linker. The safety-catch concept described here involves the use of a protected catechol derivative in which one of the hydroxyls is masked with a benzyl group during peptide synthesis, thus making the linker deactivated to aminolysis. This masked derivative of the linker allows BOC solid-phase peptide assembly of the linear precursor. Prior to cyclization, the linker is activated and the linear peptide deprotected using conditions commonly employed (TFMSA), resulting in deprotected peptide attached to the activated form of the linker. Scavengers and deprotection adducts are removed by simple washing and filtration. Upon neutralization of the N-terminal amine, cyclization with concomitant cleavage from the resin yields the cyclic peptide in DMF solution. Workup is simple solvent removal. To exemplify this strategy, several cyclic peptides were synthesized targeted toward the somatostatin and integrin receptors. From this initial study and to show the strength of this method, we were able to synthesize a cyclic-peptide library containing over 400 members. This linker technology provides a new solid-phase avenue to access large arrays of cyclic peptides.
Temperature‐controlled Rate Responsive Pacing with the Aid of an Optimized Algorithm (1987)

On the basis of earlier studies of the behavior of the central venous blood temperature at rest and during exercise, we have developed an algorithm for the rate control of cardiac pacemakers. The central venous blood temperature serves as the control variable for the pacing rate. Control is effected via two different characteristic lines that relate pacing rate and temperature. A rest characteristic line relates absolute temperature values to heart rate and exercise lines relate relative changes in temperature to heart rate changes. The rest characteristic corresponds to conditions of slow temperature fluctations (e.g., fever and temperature changes due to circardian rhythm) and has a slope of 15 to 20 bpm per centigrade degree of temperature change. Starting at this rest characteristic, there are exercise characteristic lines that have a much greater slope and serve to regulate the pacing rate under exercise conditions. The two characteristics are distinguished via the temperature change per unit of time. In addition, a return characteristic connects the rest and exercise characteristics. This algorithm allows for optimized rate adaption of physiological cardiac pacemakers by central venous blood temperature. Clinical studies with the implanted device (Intermedics Nova MR) prove the correct function and beneficial effect of this algorithm in patients' everyday life.
Near real-time modeling of global ionospheric vertical total electron content using hourly IGS data (2020)

The International GNSS Service (IGS) has been providing reliable Global Ionospheric Maps (GIMs) since 1998. The Ionosphere Associate Analysis Centers (IAACs) model the global ionospheric Total Electron Content (TEC) and generate the daily GIM products within the context of the IGS. However, the rapid and final daily GIM products have a latency of at least one day and one week or so, respectively. This limits the value of GIM products in real-time GNSS applications. We propose and develop an approach for near real-time modeling of global ionospheric TEC by using the hourly IGS data. We perform an experiment in a real operating environment to generate near real-time GIM (named BUHG) products for more than two years. Final daily GIM products, Precise Point Positioning (PPP) based VTEC resources, and JASON-3 Vertical TEC (VTEC) measurements are collected for testing the performance of BUHG. The results show that the performance of BUHG is very close to that of the daily GIM products. Also, there is good agreement between BUHG and PPP-derived VTEC as well as with JASON-3 VTEC. It is possible that BUHG would be further improved with an increase in available hourly GNSS data.
Line-up (2010)

Modular development of concurrent applications requires thread-safe components that behave correctly when called concurrently by multiple client threads. This paper focuses on linearizability, a specific formalization of thread safety, where all operations of a concurrent component appear to take effect instantaneously at some point between their call and return. The key insight of this paper is that if a component is intended to be deterministic, then it is possible to build an automatic linearizability checker by systematically enumerating the sequential behaviors of the component and then checking if each its concurrent behavior is equivalent to some sequential behavior. We develop this insight into a tool called Line-Up, the first complete and automatic checker for deterministic linearizability . It is complete, because any reported violation proves that the implementation is not linearizable with respect to any sequential deterministic specification. It is automatic, requiring no manual abstraction, no manual specification of semantics or commit points, no manually written test suites, no access to source code. We evaluate Line-Up by analyzing 13 classes with a total of 90 methods in two versions of the .NET Framework 4.0. The violations of deterministic linearizability reported by Line-Up exposed seven errors in the implementation that were fixed by the development team.
AlN Combined Overtone Resonators for the 5G mmWave Spectrum (2019)

This work presents a new acoustic MEMS resonator technology, dubbed Aluminum Nitride (AlN) Combined Overtone Resonator (COR), capable of addressing the filter requirements for the 5G mmWave spectrum in the 6-40GHz range. The COR exploits the multimodal excitation of two higher-order Lamb waves (2nd and 3rd order Asymmetrical Lamb Waves) in a suspended thin-film AlN plate to transduce a 2-dimensional vibration mode with high electromechanical coupling coefficient kt2 (up to 1.9%) and quality factor Q >1100 at twice the frequency of a fundamental thickness-extensional mode in the same structure. Analytical and finite-element method (FEM) models are developed to describe the working principle of the COR technology and predict the achievable kt2, Q and lithographic frequency tunability. An 8.8 GHz COR prototype was fabricated showing a high kt2~0.3% (using a simple top-electrode-only configuration with a 2-mask process) and a groundbreaking Q~1100 which is the highest ever achieved among piezoelectric resonators above 6 GHz. The f-Q product ~1x10e13 is the highest among all demonstrated piezoelectric resonators with metallic coverage >50%. Additionally, the capability of the COR technology to deliver contiguous filters with bandwidths between 355 and 592 MHz (aggregated BW>2GHz) in the mmWave spectrum, with relaxed lithographic requirements, is demonstrated by FEM.
Effective Antisense Gene Regulation via Noncationic, Polyethylene Glycol Brushes (2016)

Negatively charged nucleic acids are often complexed with polycationic transfection agents before delivery. Herein, we demonstrate that a noncationic, biocompatible polymer, polyethylene glycol, can be used as a transfection vector by forming a brush polymer-DNA conjugate. The brush architecture provides embedded DNA strands with enhanced nuclease stability and improved cell uptake. Because of the biologically benign nature of the polymer component, no cytotoxicity was observed. This approach has the potential to address several long-lasting challenges in oligonucleotide therapeutics.
Low Latency Live Video Streaming over HTTP 2.0 (2014)

Hypertext Transfer Protocol (HTTP) has been widely adopted as a scalable and efficient protocol for streaming video content over the Internet. HTTP streaming clients receive a manifest file, download the referred video segments over HTTP, and play them back seamlessly emulating video streaming. This introduces at least one segment duration latency making HTTP streaming unsuitable for live video streaming use cases that require low latencies. The straightforward solution to lower live latency that reduces segment duration leads to an explosion in the number of HTTP requests, as well as inefficient deployment of assets in HTTP caches. To solve this problem, we develop a low latency live video streaming technique over HTTP 2.0. In particular, we employ the new server push feature in HTTP 2.0 to stream the live video actively from the web server to the client, as soon as the video segments become available. We implement this server push based low latency mechanism in a MPEG Dynamic Adaptive Streaming over HTTP (DASH) prototype. Our experimental results indicate performance gains in live latency using the server push scheme. More importantly, by leveraging the server push feature in HTTP 2.0, we are able to avoid the request explosion problem while lowering latency by reducing the segment duration.
Identification of Determinants of Inverse Agonism in a Constitutively Active Parathyroid Hormone/Parathyroid Hormone-related Peptide Receptor by Photoaffinity Cross-linking and Mutational Analysis (2001)

We have investigated receptor structural components responsible for ligand-dependent inverse agonism in a constitutively active mutant of the human parathyroid hormone (PTH)/parathyroid hormone-related peptide (PTHrP) receptor type 1 (hP1R). This mutant receptor, hP1R-H223R (hP1R(CAM-HR)), was originally identified in Jansen's chondrodysplasia and is altered in transmembrane domain (TM) 2. We utilized the PTHrP analog, [Bpa(2),Ile(5),Trp(23),Tyr(36)]PTHrP-(1-36)-amide (Bpa(2)-PTHrP-(1-36)), which has valine 2 replaced by p-benzoyl-l-phenylalanine (Bpa); this substitution renders the peptide a photoreactive inverse agonist at hP1R(CAM-HR). This analog cross-linked to hP1R(CAM-HR) at two contiguous receptor regions as follows: the principal cross-link site (site A) was between receptor residues Pro(415)-Met(441), spanning the TM6/extracellular loop three boundary; the second cross-link site (site B) was within the TM4/TM5 region. Within the site A interval, substitution of Met(425) to Leu converted Bpa(2)-PTHrP-(1-36) from an inverse agonist to a weak partial agonist; this conversion was accompanied by a relative shift of cross-linking from site A to site B. The functional effect of the M425L mutation was specific for Bpa(2)-containing analogs, as inverse agonism of Bpa(2)-PTH-(1-34) was similarly eliminated, whereas inverse agonism of [Leu(11),d-Trp(12)]PTHrP-(5-36) was not affected. Overall, our data indicate that interactions between residue 2 of the ligand and the extracellular end of TM6 of the hP1R play an important role in modulating the conversion between active and inactive receptor states.
Minimum Lp-norm two-dimensional phase unwrapping (1996)

We develop an algorithm for the minimum Lp-norm solution to the two-dimensional phase unwrapping problem. Rather than its being a mathematically intractable problem, we show that the governing equations are equivalent to those that describe weighted least-squares phase unwrapping. The only exception is that the weights are data dependent. In addition, we show that the minimum Lp-norm solution is obtained by embedding the transform-based methods for unweighted and weighted least squares within a simple iterative structure. The data-dependent weights are generated within the algorithm and need not be supplied explicitly by the user. Interesting and useful solutions to many phase unwrapping problems can be obtained when p< 2. Specifically, the minimum L0-norm solution requires the solution phase gradients to equal the input data phase gradients in as many places as possible. This concept provides an interesting link to branch-cut unwrapping methods, where none existed previously.
Three-level two-stage decoupled active NPC converter with Si IGBT and SiC MOSFET (2017)

This paper presents the operation principle and benefits of a novel power converter topology named three-level two-stage decoupled Active Neutral Point Clamped Converter (3L-TDANPC), which is implemented based on a hybrid utilization of Si IGBTs and SiC MOSFETs. The 3L-TDANPC converter can achieve high efficiency with limited number of SiC MOSFET modules while keeping balanced distribution among the switching devices, which helps manage the converter power ratings. In addition, in this 3L-TDANPC converter, the SiC MOSFET has a potential to ride through short circuit fault because of Si IGBT. The key challenges that are associated with system resonant current is investigated and the methods to damp such current are proposed and explained in detail. The simulation and double pulse test results based on a 1-MW 3L-TDANPC converter prototype confirm the expected benefits of this proposed converter and the effectiveness of the proposed resonant current damping methods.
NUMA-aware reader-writer locks (2013)

Non-Uniform Memory Access (NUMA) architectures are gaining importance in mainstream computing systems due to the rapid growth of multi-core multi-chip machines. Extracting the best possible performance from these new machines will require us to revisit the design of the concurrent algorithms and synchronization primitives which form the building blocks of many of today's applications. This paper revisits one such critical synchronization primitive -- the reader-writer lock.
Diagnosis of application server performance problems via thread level pattern analysis (2011)

Task level breakdown provides high level information for operation performance bottleneck analysis. Creating a task level breakdown requires prior knowledge of the application server program logic and can be very time consuming. In this paper, we present yShark, a profiling tool which generates a task level breakdown chart automatically without prior knowledge. With thread level pattern analysis, performance bottlenecks can be easily located. We illustrate the innovative features of this tool with two real-world application case studies. First, we show how performance bottlenecks from modules both within and external to the system can be easily identified by the tool; second, we present a pattern detection and pattern matching algorithm to detect duplicate sequential tasks that can be run in parallel. We also show how this tool can be useful in VMware vCloud Director production environments due to the minimal profiling overhead.