gebhart/patrepeval huggingface dataset:
Force and Stiffness Backstepping-Sliding Mode Controller for Pneumatic Cylinders (2014)

In most applications that involve human-robot interactions, such as prosthetics, orthotics, rehabilitation, and locomotion, compliant actuators with variable stiffness can be used to improve safety and comfort of the device. Another advantage of the stiffness control is minimizing the energy consumption by adjusting the stiffness of the actuator to the natural stiffness of the controlled system. This paper introduces a new backstepping-sliding mode force-stiffness controller for pneumatic cylinders. The global ultimate-bounded stability of the closed-loop system was proven by the Lyapunov method. Based on a detailed mathematical model of the pneumatic system that includes the dynamics of the valves, the algorithm was proven able to track the desired force and stiffness independently without chattering. Validating experiments using a real-time platform were performed for a pneumatic cylinder suitable for wearable robotics applications. The performance of the proposed algorithm was compared with the performance of a previously reported pneumatic force-stiffness sliding mode controller.
Burner Development and Operability Issues Associated with Steady Flowing Syngas Fired Combustors (2008)

This article addresses the impact of syngas fuel composition on combustor blowout, flashback, dynamic stability, and autoignition in premixed, steady flowing combustion systems. These are critical issues to be considered and balanced against emissions considerations in the development and operation of premixed combustors. Starting with blowout, the percentage of hydrogen in the fuel is suggested to be the most significant fuel parameter, which is more fundamentally related to the hydrogen flame's resistance to stretch induced extinction. Turning to flashback next, it is shown that multiple flashback mechanisms are present in swirling flows, and the key thermophysical properties of a syngas mixture that influence its flashback proclivity depend upon which flashback mechanism is considered. Flashback due to turbulent flame propagation in the core flow and the interaction of heat release with pulsations are less critical, whereas flame propagation in boundary layers and flashback due to the interaction of the heat release with vortex breakdown dynamics are most significant. Then, combustion instability is considered. The key flame parameter impacting the conditions under which instabilities occur is the spatial distribution of the flame. As such, fuel composition influences dynamics through impacts upon flame speed and the flame stabilization point. Furthermore, certain syngas fuel compositions are not more inherently stable than others – rather, each mixture has particular islands in the parameter space of, e.g., velocity and fuel/air ratio, at which instabilities occur. Changes in fuel composition move these islands around but do not necessarily eliminate or introduce instabilities. Relative to autoignition, measurements indicate that the ignition delay time exceeds typical premixer residence times, though by a substantially less margin than suggested by the calculations. Recent experiment work suggest that current detailed kinetic mechanisms developed for hydrogen/carbon monoxide ignition overestimate the ignition delay time, indicating the need for additional kinetic work in the low temperature, high pressure regime.
MS <sup>3</sup> using the collision cell of a tandem mass spectrometer system (2002)

We report the feasibility of multistage fragmentation in combination with a fast background subtraction method, yielding the equivalent of MS3. The first quadrupole selects an ion of interest, and the ion is axially accelerated into Q2 to generate fragment ions. Subsequent stages of mass selection and fragmentation are obtained by quadrupolar resonant excitation within the Q2 collision cell. The fragments are analyzed downstream by either a resolving quadrupole or a time-of-flight (TOF) mass spectrometer, and multistage spectra are obtained by subtraction (MS(n) - MS(n-1)) for n = 3 or 4. We discuss the characterization of this method, including product ion arrival times, fragmentation efficiencies, and ion selectivity. We report accurate TOF mass spectra of background-subtracted MS3 for protonated molecules reserpine (m/z 609), bosentan (m/z 1552), and taxol (m/z 854).
Multidetector CT assessment of partial anomalous pulmonary venous return in association with sinus venosus type atrial septal defect. (2014)

Sinus venosus defects account for 15% of all atrial septal defects. They are frequently associated with partial anomalous pulmonary venous drainage of the right superior pulmonary vein into the superior vena cava (SVC). These defects require surgical correction and accurate pre-operative imaging assessment is critical. We present a case of sinus venosus atrial septal defect in which multidetector computed tomography (MDCT) angiography identified separate sites of pulmonary venous return.
Treatment of disseminated ovarian cancer using nonviral interleukin‐12 gene therapy delivered intraperitoneally (2009)

Taken together, these results suggest that pmIL-12/PPC may be an effective strategy for inhibiting progression of disseminated ovarian cancer and may offer a new option for treatment of advanced disease that can be used to complement standard therapies.
Active regulation of receptor ratios controls integration of quorum‐sensing signals in <i>Vibrio harveyi</i> (2011)

Quorum sensing is a chemical signaling mechanism used by bacteria to communicate and orchestrate group behaviors. Multiple feedback loops exist in the quorum-sensing circuit of the model bacterium Vibrio harveyi. Using fluorescence microscopy of individual cells, we assayed the activity of the quorum-sensing circuit, with a focus on defining the functions of the feedback loops. We quantitatively investigated the signaling input-output relation both in cells with all feedback loops present as well as in mutants with specific feedback loops disrupted. We found that one of the feedback loops regulates receptor ratios to control the integration of multiple signals. Together, the feedback loops affect the input-output dynamic range of signal transmission and the noise in the output. We conclude that V. harveyi employs multiple feedback loops to simultaneously control quorum-sensing signal integration and to ensure signal transmission fidelity.
Efficiency of conversion of laser radiation into electrical energy (1987)

It was found that the emission currents created by the interaction of two consecutive pulses with a target in vacuum can be increased if the energy carried by the first pulse is an order of magnitude less than that of the main pulse. The dependence of the current on the laser radiation energy is reported.
Stochastic Integration Filter (2013)

The technical note deals with state estimation of nonlinear stochastic dynamic systems. Traditional filters providing local estimates of the state, such as the extended Kalman filter, unscented Kalman filter, or the cubature Kalman filter, are based on computationally efficient but approximate integral evaluations. On the other hand, the Monte Carlo based Kalman filter takes an advantage of asymptotically exact integral evaluations but at the expense of substantial computational demands. The aim of the technical note is to propose a new local filter that utilises stochastic integration methods providing the asymptotically exact integral evaluation with computational complexity similar to the traditional filters. The technical note will demonstrate that the unscented and cubature Kalman filters are special cases of the proposed stochastic integration filter. The proposed filter is illustrated by a numerical example.
Mass production of volume holographic optical elements (vHOEs) using Bayfol<sup>®</sup> HX photopolymer film in a roll-to-roll copy process (2017)

Volume Holographic Optical Elements (vHOEs) gained wide attention as optical combiners for the use in augmented and virtual reality (AR and VR, respectively) consumer electronics and automotive head-up display applications. The unique characteristics of these diffractive grating structures – being lightweight, thin and flat – make them perfectly suitable for use in integrated optical components like spectacle lenses and car windshields. While being transparent in Off-Bragg condition, they provide full color capability and adjustable diffraction efficiency. The instant developing photopolymer Bayfol&reg; HX film provides an ideal technology platform to optimize the performance of vHOEs in a wide range of applications. Important for any commercialization are simple and robust mass production schemes. In this paper, we present an efficient and easy to control one-beam recording scheme to copy a so-called master vHOE in a step-and-repeat process. In this contact-copy scheme, Bayfol&reg; HX film is laminated to a master stack before being exposed by a scanning laser line. Subsequently, the film is delaminated in a controlled fashion and bleached. We explain working principles of the one-beam copy concept and discuss the mechanical construction of the installed vHOE replication line. Moreover, we treat aspects like master design, effects of vibration and suppression of noise gratings. Furthermore, digital vHOEs are introduced as master holograms. They enable new ways of optical design and paths to large scale vHOEs.
Integrated photonics in the future: Silicon, plasmonics or something else? (2010)

In anticipation of a possible future breakthrough in developing metamaterials with at least a factor of 10 lower losses we analyze in this paper different resonant and nonresonant structures and the achievable performance. One example is waveguides made from arrays of near resonantly operated near-field coupled metal nanoparticles in the shape of e.g. spheres, which have attracted some attention. Nanoarray waveguides, based on silver nanoparticles are, however, very lossy, see e.g.
Improving the STEM Spatial Resolution Limit (2018)

An abstract is not available for this content so a preview has been provided. As you have access to this content, a full PDF is available via the 'Save PDF' action button.
DETECTION OF ILLICIT DRUGS AND DRUG PRECURSORS WITH CANTILEVER-ENHANCED PHOTOACOUSTIC SPECTROSCOPY (2014)

In this study, cantilever-enhanced photoacoustic spectroscopy (CEPAS) was applied in different drug detection schemes. The study was divided into two different applications: trace detection of vaporized drugs and drug precursors in the gas-phase, and detection of cocaine abuse in hair. The main focus, however, was the study of hair samples. In the gas-phase, methyl benzoate, a hydrolysis product of cocaine hydrochloride, and benzyl methyl ketone (BMK), a precursor of amphetamine and methamphetamine were investigated. In the solid-phase, hair samples from cocaine overdose patients were measured and compared to a drug-free reference group. As hair consists mostly of long fibrous proteins generally called keratin, proteins from fingernails and saliva were also studied for comparison.&#13;\n&#13;\nDifferent measurement setups were applied in this study. Gas measurements were carried out using quantum cascade lasers (QLC) as a source in the photoacoustic detection. Also, an external cavity (EC) design was used for a broader tuning range. Detection limits of 3.4 particles per billion (ppb) for methyl benzoate and 26 ppb for BMK in 0.9 s were achieved with the EC-QCL PAS setup. The achieved detection limits are sufficient for realistic drug detection applications.&#13;\n&#13;\nThe measurements from drug overdose patients were carried out using Fourier transform infrared (FTIR) PAS. The drug-containing hair samples and drug-free samples were both measured with the FTIR-PAS setup, and the measured spectra were analyzed statistically with principal component analysis (PCA). The two groups were separated by their spectra with PCA and proper spectral pre-processing. To improve the method, ECQCL measurements of the hair samples, and studies using photoacoustic microsampling techniques, were performed. High quality, high-resolution spectra with a broad tuning range were recorded from a single hair fiber. This broad tuning range of an EC-QCL has not previously been used in the photoacoustic spectroscopy of solids. However, no drug detection studies were performed with the EC-QCL solid-phase setup.
ChemInform Abstract: Collisionally Activated Dissociation of Some Bulky Substituted Pyridinium Cations. Part 2. Substituent Effect on Appearance Potential (1992)

Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Evaluation of possible drug–drug interaction between gadoxetic acid and erythromycin as an inhibitor of organic anion transporting peptides (OATP) (2011)

Coadministration of erythromycin has no effect on gadoxetic acid enhanced liver MR imaging.
Discontinuous Fiber-Reinforced Composites (2020)

You have accessDiscontinuous Fiber-Reinforced CompositesMar 2020Discontinuous Fiber-Reinforced CompositesUmesh N. Gandhi, Sebastian Goris, Tim A. Osswald, Yu-Yang SongUmesh N. Gandhi, Sebastian Goris, Tim A. Osswald, Yu-Yang Songhttps://doi.org/10.3139/9781569906958.fmSectionsAboutPDF ToolsAdd to FavoritesDownload CitationTrack CitationsCopy LTI LinkPDF key 'share (en)' returned an object instead of string.FacebookTwitterEmailLinkedIn next chapter FiguresReferencesRelatedDetails 2020Pages: I-XIVPrint ISBN: 978-1-56990-694-1eISBN: 978-1-56990-695-8 Copyright & PermissionsCopyright by Carl Hanser Verlag GmbH & Co. KGPDF downloadLoading ...
Power Scaling of SM Fiber Lasers toward 10kW (2009)

The physical and engineering challenges in scaling fiber lasers toward 10kW include 1) avoiding non-linear thresholds, particularly SRS, 2) obtaining sufficient pump brightness, and 3) overcoming thermal issues. The methods to overcome these barriers are reviewed and results &gt;6kW SM are provided. Article not available.
<i>Bacillus subtilis</i> Esterase (BS2) and its Double Mutant Have Different Selectivity in the Removal of Carboxyl Protecting Groups (2009)

Abstract An esterase from Bacillus subtilis (BS2) and its double mutant E188W/M193C quickly hydrolyze n ‐butyl, n ‐propyl, methoxyethyl and allyl esters. The wild‐type BS2 preferentially removes such esters from the γ‐position of glutamate diesters, while the engineered enzyme has a reversed selectivity removing esters from the α‐position of glutamate diesters. Automated docking and molecular dynamic simulations were performed to understand the molecular reason for the different regioselectivity.
Tenfibgen-DMAT Nanocapsule Delivers CK2 Inhibitor DMAT to Prostate Cancer Xenograft Tumors Causing Inhibition of Cell Proliferation. (2014)

CK2 is a master regulator protein kinase which demonstrates heightened expression in diverse cancer types and is considered a promising target for therapy. Given its ubiquitous expression and potent influence on cell survival, cancer cell-directed targeting of the CK2 signal is an important factor for development of an anti-CK2 therapeutic. We previously reported on the malignant cell specificity and effect on CK2 signaling of a tenfibgen (TBG) based nanocapsule for delivery of the CK2 small molecule inhibitor 2-dimethylamino-4,5,6,7-tetrabromo-1<i>H</i>-benzimidazole (DMAT) in cultured prostate cancer cells. Here we tested the ability of TBG-DMAT to affect the growth of prostate xenograft tumors in mice. Our results show that treatment of PC3-LN4 xenograft tumors with TBG-DMAT caused loss of proliferative Ki-67 signal as well as Nuclear Factor-kappa B (NF-κB) expression in the tumors. Further, the TBG-DMAT nanocapsule was detected in tumors and not in liver or testis. In conclusion, TBG-based nanocapsule delivery of anti-CK2 small molecule drugs holds significant promise for treatment of prostate cancer.
&lt;title&gt;New ultrathin 3D integration technique: technological and thermal investigations&lt;/title&gt; (2000)

A new vertical chip integration is proposed, based on the UTCS concept. It consists in stacking thinned chips on top of a silicon substrate. Lateral and vertical metal interconnections and the thinned chips are embedded in BCB layers. This wafer scale integration technique is presented. Thermal behavior of such stacked structure is also discussed.
Superconductivity of overdoped cuprates: the modern face of the ancestral two-electron exchange (2003)

The single-site two-electron exchange amplitude J_sd between the Cu 4s and Cu 3d_{x^2-y^2} states is found to be the pairing mechanism of high-T_c overdoped cuprates. The noninteracting part of the Hamiltonian spans the copper Cu 4s, Cu 3d_{x^2-y^2} and oxygen O 2p_x and O 2p_y states. Within the standard BCS treatment an explicit expression for the momentum dependence of the gap Delta_p is derived and shown to fit the angle-resolved photoemission spectroscopy (ARPES) data. The basic thermodynamic and electrodynamic properties of the model (specific heat C(T), London penetration depth lambda(T)) are analytically derived. These are directly applicable to cuprates without complicating structural accessories (chains, double CuO_2 planes, etc.). We advocate that the pairing mechanism of overdoped and underdoped cuprates is the same, as T_c displays smooth doping dependence. Thus, a long-standing puzzle in physics is possibly solved.
Automatic Summarization of Conversational Multi-Party Speech (2006)

Document summarization has proven to be a desirable component in many information management systems, complementing core information retrieval and browsing functionalities. The use of document summarization techniques is especially important with speech documents such as meeting transcriptions, since they are particularly difficult to navigate. As opposed to their written counterparts, spoken documents lack structural elements like title, headers, and paragraphs that can ease the task of the information seeker. Document summarization can reduce the overhead of navigating large collections of speech data. For example, summarization techniques can be used to extract or highlight relevant passages in a full transcription. Alternatively, similar techniques might be used to generate short text substitutes, or abstracts, that capture the “aboutness” of the meeting, while discarding disfluencies and other unimportant elements.
Adsorbed Xenon Propellant Storage: Are Nanoporous Materials Worth the Weight? (2021)

Xenon is used as a propellant for spacecraft. Conventionally, xenon is compressed to high pressures (75-300 bar) for bulk storage onboard the spacecraft. An adsorbed xenon storage system based on nanoporous materials (NPMs) could, potentially, (i) reduce the storage pressures, (ii) allow for thinner-walled and lighter pressure vessels, and (iii) if the NPM itself is sufficiently light, reduce the overall mass of the storage system and thus of the payload of the rocket launch.&lt;br&gt;&lt;br&gt;To investigate, we develop a simple mathematical model of an adsorbed xenon storage system by coupling a mechanical model for the pressure vessel and a thermodynamic model for the density of xenon adsorbed in the NPM. From the model, we derive the optimal storage pressure, tailored to each NPM, with the objective of minimizing the mass of the storage materials (walls of the pressure vessel + NPM) required to store the xenon. The model enables us to: (i) rank NPMs for adsorbed xenon propellant storage, (ii) compare adsorbed storage to the baseline of bulk storage, and (iii) understand what properties of NPMs are desirable for adsorbed xenon propellant storage.&lt;br&gt;&lt;br&gt;We use the model to evaluate several NPMs, mostly metal-organic frameworks (MOFs), for adsorbed xenon propellant storage at room temperature, using experimental xenon adsorption data as input. We find Ni-MOF-74 and MOF-505 outperform the traditional adsorbent, activated carbon. However, we find each optimized adsorbed xenon storage system is heavier than the optimized bulk storage system, owing dominantly to the large mass of the NPM itself. Our model suggests that, for a NPM to provide a lighter adsorbed xenon storage system compared to bulk storage, the saturation loading of xenon in the adsorbent must exceed ca. 94 mmol Xe/g adsorbent.
Bilevel programming for analysis of low-complexity control of linear systems with constraints (2009)

In this paper we use bilevel programming to find the maximum difference between a reference controller and a low-complexity controller in terms of the infinity-norm difference of their control laws. A nominal MPC for linear systems with constraints, and a robust MPC for linear systems with bounded additive noise are considered as reference controllers. For possible low-complexity controllers we discuss partial enumeration (PE), Voronoi/closest point, triangulation, linear controller with saturation, and others. A small difference in the norm between a low-complexity controller and a robust MPC may be used to guarantee closed-loop stability of the low-complexity controller and indicate that the behaviour or performance of the low-complexity controller will be similar to that of the reference one. We further discuss how bilevel programming may be used for closed-loop analysis of model reduction.
Provenance in Databases: Why, How, and Where (2007)

In September 2008, Google News promoted an undated article about United Airlines' near bankruptcy in 2002. In the ensuing panic, the share price of United Airlines dropped by around 75% in a few hours. This problem was due in part to the fact that the article lacked provenance that readers could have used to determine that it was out of date. In an increasingly networked world, understanding of provenance is essential for establishing trust in data stored in databases and exchanged among Web sites. It is also critical to the process of making key business, scientific, and governmental decisions. Modern database systems are capable of producing answers efficiently. However, they are generally lacking capabilities to explain provenance such as why and how the answers were produced, or where the data in the result came from. In recent years, different notions of provenance for database queries have been studied by the authors and a growing community of researchers in databases and scientific computation. Provenance in Databases reviews research over the past ten years on why, how, and where provenance, clarifies the relationships among these notions of provenance, and describes some of their applications in confidence computation, view maintenance and update, debugging, and annotation propagation. Provenance in Databases is intended for engineers and researchers who would like to familiarize themselves with the foundations, as well as the many challenges in the field of database provenance.
Local structure of temperature and pH-sensitive colloidal microgels (2015)

The temperature dependence of the local intra-particle structure of colloidal microgel particles, composed of interpenetrated polymer networks, has been investigated by small-angle neutron scattering at different pH and concentrations, in the range (299÷315) K, where a volume phase transition from a swollen to a shrunken state takes place. Data are well described by a theoretical model that takes into account the presence of both interpenetrated polymer networks and cross-linkers. Two different behaviors are found across the volume phase transition. At neutral pH and T ≈ 307 K, a sharp change of the local structure from a water rich open inhomogeneous interpenetrated polymer network to a homogeneous porous solid-like structure after expelling water is observed. Differently, at acidic pH, the local structure changes almost continuously. These findings demonstrate that a fine control of the pH of the system allows to tune the sharpness of the volume-phase transition.