gebhart/patrepeval huggingface dataset:
A review of soft-switched DC-AC converters (1998)

Soft-switching techniques have recently been applied in the design of DC-AC power converters, in order to achieve better performance, higher efficiency and higher power density. A substantial number of new topologies for different applications has been developed, however the amount of work that has been done in this field is not widely known. This paper is an attempt to classify the soft-switched DC-AC topologies in a simple and generic way. The topology classifications are based on the location of the resonant network (load, inverter bridge, and bus), the characteristic of switching waveforms (zero-voltage switching or zero-current switching), and the type of resonance (series or parallel), operating principles, performance, and design limitations are discussed. Some possible industrial applications of soft-switched DC-AC power converters are also addressed.
Acute voltage, charge, and energy thresholds as functions of electrode size for electrical stimulation of the canine heart (1979)

This paper analyses the relationships between electrode size and charge, voltage, and energy thresholds in acute animal experiments. Cathodal stimuli of 1 ms duration are applied to canine hearts by using epicardial disc electrodes. Threshold charge in constant current and in constant voltage stimulation proves to be proportional to the electrode radius (a) to the power 1.5 for a greater than 0.4 mm and to be independent of electrode size for a less than 0.2 mm. Voltage and energy thresholds are proportional to square root a and a2 respectively for a greater than 1 mm. Voltage thresholds show a minimum at a radius of about 0.5 mm, energy thresholds at about 0.3 mm. These results are explained by using two principles. The first is that the charge applied to the heart determines the response of the tissue to a stimulus and the second, that electrode impedance may be described by an RC-series circuit in these experiments. The resistance in this circuit is inversely proportional to electrode radius, in agreement with calculation of the electric field around the electrode. Electrode capacity depends linearly on electrode surface area. Stimulation is most efficient under the circumstances mentioned above for an electrode radius of about 0.3 mm.
Deep-Reinforcement-Learning-Based Autonomous Voltage Control for Power Grid Operations (2019)

In this letter, a novel autonomous control framework “Grid Mind” is proposed for the secure operation of power grids based on cutting-edge artificial intelligence (AI) technologies. The proposed platform provides a data-driven, model-free and closed-loop control agent trained using deep reinforcement learning (DRL) algorithms by interacting with massive simulations and/or real environment of a power grid. The proposed agent learns from scratch to master the power grid voltage control problem purely from data. It can make autonomous voltage control (AVC) strategies to support grid operators in making effective and timely control actions, according to the current system conditions detected by real-time measurements from supervisory control and data acquisition (SCADA) or phasor measurement units (PMUs). Two state-of-the-art DRL algorithms, namely deep Q-network (DQN) and deep deterministic policy gradient (DDPG), are proposed to formulate the AVC problem with performance compared. Case studies on a realistic 200-bus test system demonstrate the effectiveness and promising performance of the proposed framework.
Total Synthesis of (+-)-17β-Hydroxy-Δ<sup>9(10)</sup>-des-A-androsten-5-one [(+-)-2,3,3a,4,5,7,8,9,9aβ,9bα-Decahydro-3β-hydroxy-3aβ6-dimethyl-1H-benz[e]inden-7-one] (1967)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTTotal Synthesis of (+-)-17β-Hydroxy-Δ9(10)-des-A-androsten-5-one [(+-)-2,3,3a,4,5,7,8,9,9aβ,9bα-Decahydro-3β-hydroxy-3aβ6-dimethyl-1H-benz[e]inden-7-one]Zoltan Hajos, Robert Micheli, David Parrish, and Eugene OlivetoCite this: J. Org. Chem. 1967, 32, 10, 3008–3010Publication Date (Print):October 1, 1967Publication History Published online12 August 2003Published inissue 1 October 1967https://pubs.acs.org/doi/10.1021/jo01285a601https://doi.org/10.1021/jo01285a601research-articleACS PublicationsRequest reuse permissionsArticle Views783Altmetric-Citations3LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts
<i>ScyFlow</i>: an environment for the visual specification and execution of scientific workflows (2005)

Abstract With the advent of Grid technologies, scientists and engineers are building more complex applications to utilize distributed Grid resources. Core Grid services provide a path for accessing and utilizing these resources in a secure and seamless fashion. However, what the scientists need is an environment that will allow them to specify their application runs at a high organizational level, and then will support efficient execution across any given set or sets of distributed resources. We have been designing and implementing ScyFlow , a dual‐interface architecture, both Graphical User Interface (GUI) and Application Programming Interface (API), that addresses this problem. The scientist/user specifies the application tasks along with the necessary control and data flow, and then monitors and manages the execution of the resulting workflow across the distributed resources. In this paper, we utilize two scenarios to provide the details of the two modules of the project, the visual editor and the runtime workflow engine. Published in 2005 by John Wiley & Sons, Ltd.
Evidence for unlimited capacity processing of simple features in visual cortex (2017)

Performance in many visual tasks is impaired when observers attempt to divide spatial attention across multiple visual field locations. Correspondingly, neuronal response magnitudes in visual cortex are often reduced during divided compared with focused spatial attention. This suggests that early visual cortex is the site of capacity limits, where finite processing resources must be divided among attended stimuli. However, behavioral research demonstrates that not all visual tasks suffer such capacity limits: The costs of divided attention are minimal when the task and stimulus are simple, such as when searching for a target defined by orientation or contrast. To date, however, every neuroimaging study of divided attention has used more complex tasks and found large reductions in response magnitude. We bridged that gap by using functional magnetic resonance imaging to measure responses in the human visual cortex during simple feature detection. The first experiment used a visual search task: Observers detected a low-contrast Gabor patch within one or four potentially relevant locations. The second experiment used a dual-task design, in which observers made independent judgments of Gabor presence in patches of dynamic noise at two locations. In both experiments, blood-oxygen level-dependent (BOLD) signals in the retinotopic cortex were significantly lower for ignored than attended stimuli. However, when observers divided attention between multiple stimuli, BOLD signals were not reliably reduced and behavioral performance was unimpaired. These results suggest that processing of simple features in early visual cortex has unlimited capacity.
Establishment of bone marrow and hematopoietic niches in vivo by reversion of chondrocyte differentiation of human bone marrow stromal cells (2014)

Human bone marrow stromal cells (BMSCs, also known as bone marrow-derived "mesenchymal stem cells") can establish the hematopoietic microenvironment within heterotopic ossicles generated by transplantation at non-skeletal sites. Here we show that non-mineralized cartilage pellets formed by hBMSCs ex vivo generate complete ossicles upon heterotopic transplantation in the absence of exogenous scaffolds. These ossicles display a remarkable degree of architectural fidelity, showing that an exogenous conductive scaffold is not an absolute requirement for bone formation by transplanted BMSCs. Marrow cavities within the ossicles include erythroid, myeloid and granulopoietic lineages, clonogenic hematopoietic progenitors and phenotypic HSCs, indicating that complete stem cell niches and hematopoiesis are established. hBMSCs (CD146(+) adventitial reticular cells) are established in the heterotopic chimeric bone marrow through a unique process of endochondral bone marrow formation, distinct from physiological endochondral bone formation. In this process, chondrocytes remain viable and proliferate within the pellet, are released from cartilage, and convert into bone marrow stromal cells. Once explanted in secondary culture, these cells retain phenotype and properties of skeletal stem cells ("MSCs"), including the ability to form secondary cartilage pellets and secondary ossicles upon serial transplantation. Ex vivo, hBMSCs initially induced to form cartilage pellets can be reestablished in adherent culture and can modulate gene expression between cartilage and stromal cell phenotypes. These data show that so-called "cartilage differentiation" of BMSCs in vitro is a reversible phenomenon, which is actually reverted, in vivo, to the effect of generating stromal cells supporting the homing of hematopoietic stem cells and progenitors.
Exponential energy harvesting through repetitive reconfigurations of a system of capacitors (2018)

Abstract In conventional energy harvesting systems, energy can be extracted from a fixed-level source at a constant rate at best. The resulting growth of harvested energy is bound by a linear function. Here we show that exponential energy harvesting can be achieved in a system of reconfigurable energy storage elements. The exponential extraction results from the positive feedback of the system potential energy due to repetitive system reconfigurations. The concept is studied theoretically and validated with results from systems of droplet capacitors. A device with three 300 μL mercury drops can generate an exponentially growing voltage that reaches 168 V within a few cycles of a low-level and low-frequency mechanical excitation. The same device with water drops can generate a similarly growing voltage that reaches 56 V. This concept holds potential in DC power generation and may be applied in other energy domains.
On Molecular Structure and Physical Properties of Thermotropic Liquid Crystals (1969)

Abstract Some models for the molecular structures of liquid crystals including a ferroelectric liquid are discussed. It is shown that a smectic liquid with a layered structure, in which the preferred orientation of the molecular axis is inclined against the layers, has some similarities with a nematic liquid. Such a tilted smectic liquid may also have a twisted modification corresponding to a twisted nematic or cholesteric liquid crystal. Attention is drawn to an optically isotropic texture of a cholesteric liquid. A proposal is made for its molecular structure in which a fairly regular, lattice-like arrangement of alignment singularities is assumed. Twist waves in nematic liquids are regarded and numerical estimations are made for their wave velocity and damping in p-azoxyanisole. It is concluded that the damping is too strong for an observation of such waves.
Ecosystem for Engineering Design Learning: A Comparative Analysis (2017)

Design is a human activity that encompasses a broad array of tasks. In engineering design, individual efforts can be aggregated into teams to maximize collective progress. Effective teamwork, however, requires extensive management, organization and communication. Furthermore, modern challenges encompass complicated multi-disciplinary problems with faster schedules, fewer resources, and greater demands. Design, as a process, can be dissected into characteristic phases. Within each phase, design solutions are gradually developed. Technological tools have prioritized the structured analyses of the detail and final design phases and have proven to be powerful multipliers for effective design efforts. It has long been the case, however, that major commitments of intangible resources are made as a result of efforts in the less emphasized earlier phases. These commitments and lack of modern toolsets for requirement development and conceptual design activities materialize as major sources of design pitfalls, both in industry and on student design projects. This paper presents a digital Ecosystem for Engineering Design Learning as a comprehensive, yet flexible, framework for capstone design teams. The digital Ecosystem has been developed as a feasible technology to bolster student information management, teamwork, communication, and proficiency in fundamental design principles, and as a technology capable of alleviating rework and process-related productivity interruptions. Its primary innovation, for capstone applications, is the ability to assess design work automatically against the design process, as well as against ABET compliant learning objectives, and provide prompt advisories in case of design oversights. The digital Ecosystem is compared to tools for project management, team communication, and requirement management.
Gray-scale character image recognition based on fuzzy DCT transform features (2002)

We propose a method for recognizing gray-scale text images with noise and of extraordinary low resolution. First, a fuzzy classification of pixels in the gray-scale character images is applied to form the fuzzy attributed pixel graph using integral ratio techniques. Second, a DCT transform is applied on this fuzzy graph and parts of the frequency domain components are selected and compressed to produce the features for recognition. By using the modified quadratic discriminant function in the classifier, we achieve satisfactory recognition results with the average recognition rate of 96.82% on 15 pixel/spl times/15 pixel character images and at the speed of over 30 characters/s.
Three-Phase Controlled Expansion Superalloys with Oxidation Resistance (1992)

Due to their low coefficients of thermal expansion, lNCOLOY@ alloys 903, 907 and 909 have contributed to improved efficiency in many aircraft engines designed since the mid '70's. The application of these Cr-free superalloys was, however, limited by inadequate oxygen environment resistance. The alloys were susceptible to both general oxidation and SAGBO (Stress Accelerated Grain Boundary Oxygen) embrittlement. Until just recently development efforts had focused on improving SAGBO resistance, but had ignored general oxidation resistance. This paper reviews the status of a major, ongoing alloy research program on a new, low CTE superalloy system with improved environmental resistance. While early experiments confirmed that Al-containing alloys were extremely prone to SAGBO (as were alloys 903 with 1% Al and the intermetallic NisAI), continued research led to the unexpected discovery of a dramatic improvement in SAGBO resistance as Al exceeded 5% ,* This improvement was associated with the appearance of an Al-rich BCC phase (B). The resulting development of this three-phase (r-r'--@) alloy system is described, and numerous metallurgical challenges are addressed. The system's phase balance and properties are shown to be strongly dependent on the matrix elements as well as Al. Solutions to B phase anisotropy include control of Al and thermomechanical processing (TMP). An unexpected instability at "intermediate" temperatures (45O"C-650C) is correlated with Fe, Ti and Nb content.
Flexible Organic Electroluminescent Devices Based on Fluorine-Containing Colorless Polyimide Substrates (2002)

A fluorine-containing polyimide (PI) has been used as a substrate for a flexible organic electroluminescent device. An indium tin oxide (ITO) thin film on the PI substrate is shown to yield a high performance for the device, comparable to that of devices with conventional ITO-coated glass substrates. The Figure shows a photograph of the working device under a flexing load.
Formation of random copolymers (1966)

Abstract Assumptions in the derivation of the copolymerization equation, experimental errors in its application, and recent developments in quantitative correlations of reactivity data in free radical polymerizations are considered. Fewer monomers are susceptible to cationic or anionic polymerizations and differences in reactivity among these monomers are so large that practical possibilities of making copolymers by ionic reactions are limited. Numerous experimental variables complicate assembly and correlation of experimental data on ionic copolymerizations and the present status of such efforts is summarized. Similar considerations apply also, often to a greater degree, to copolymerizations by transition metal and metal oxide catalysts. Some simple expressions for monomer distributions in copolymers are given.
The behavioral response of mice to gaps in noise depends on its spectral components and its bandwidth (2005)

The purpose of these experiments was to determine whether detecting brief decrements in noise level ("gaps") varies with the spectral content and bandwidth of noise in mice as it does in humans. The behavioral effect of gaps was quantified by their inhibiting a subsequent acoustic startle reflex. Gap durations from 1 to 29 ms were presented in five adjacent 1-octave noise bands and one 5-octave band, their range being 2 kHz to 64 kHz. Gaps ended 60 ms before the startle stimulus (experiment 1) or at startle onset (experiment 2). Asymptotic inhibition was greater for higher-frequency 1-octave bands and highest for the 5-octave band in both experiments, but time constants were related to frequency only in experiment 1. For the lowest band (2-4 kHz) neither noise decrements (experiment 1 and 2) nor increments (experiment 3) had any behavioral consequence, but this band was effective when presented as a pulse in quiet (experiment 4). The lowest frequencies in the most effective 1-octave band were one octave above the spectral region where mice have their best absolute thresholds. These effects are similar to those obtained in humans, and reveal a special contribution of wide band, high-frequency stimulation to temporal acuity.
A Pilot Trial of GM-CSF and MDX-H210 in Patients with erbB-2-Positive Advanced Malignancies (1999)

MDX-H210 is a chemically, cross-linked, half-humanized bispecific antibody composed of F(ab') fragment from monoclonal antibody (mAb) H22 that binds to the high-affinity receptor Fc gamma RI and F(ab') of mAb 520C9 that recognizes the erbB-2 (HER2/neu) oncoprotein. In a previous trial, the murine bispecific, MDX-210 at a dose of 7 mg/m2, was well tolerated and activated monocytes and macrophages in vivo in doses as low as 0.35 mg/m2. In our multidose trial, granulocyte-macrophage colony-stimulating factor, which increases and activates potential effector cells, was given on days 1-4 at 250 micrograms/m2 s.c. and MDX-H210 was given on day 4 weekly for 4 consecutive weeks. Thirteen patients were treated at dose levels of 1, 3.5, 7, 10, 15, and 20 mg/m2 without dose-limiting toxicity. Fever, chills, and rigors occurred during and up to 2 h postinfusion and correlated with the time to peak levels of tumor necrosis factor-alpha (median 88.2 pg/ml; range 15.6-887 pg/ml) and interleukin-6 (median 371 pg/ml; range 175-2,149 pg/ml). By the fourth consecutive week of treatment the side effects and cytokine levels decreased significantly. Human antibispecific antibody (HABA) levels were increased by 200- to 500-fold above pretreatment levels in 5 of 11 evaluable patients after 3 weeks of treatment. The monocyte and granulocyte population increased on days 4 and 11 (median 44%; range 18-68% and 42%; 19-71%), respectively, for monocytes and (60%; 43-75% and 74%; 54-82%) on days 4 and 11 for granulocytes. There was a significant decrease in the monocyte populations immediately after MDX-H210 administration (median decrease 73%; range 42-94%) and (52%; 12-72%) on days 4 and 11, respectively. Ten patients completed 4 weeks of treatment. One patient had a 48% reduction in an index lesions and six patients had stable disease at the time of evaluation. Three patients progressed before the fourth week. The therapy was generally well tolerated with toxicity, primarily, limited to the days of treatment.
Gas Sensing Properties of Semiconducting Metal Oxide Thin Films (2012)

Gas sensors based on semiconducting metal oxide nanostructures are expected to exhibit better sensing properties like sensitivity and selectivity, than gas sensors based on other materials. Majority of the semiconducting materials possess n-type conduction and it is due to the presence of bulk oxygen vacancies. The sensitivity of the semiconducting material depends on the surface reaction between the chemisorbed oxygen and the reducing gases. Optimized indium zinc oxide thin films deposited at room temperature by electron beam evaporation technique were engaged as sensing elements for the detection of ethanol in this present study.
Structural origin of magnetic biased field in NiMn/NiFe exchange coupled films (1996)

The factors which determine the strength of the magnetic biased field in NiMn/NiFe exchange biased system have been examined. It was found that a strong NiFe (111) texture and columnar growth are essential to obtaining a high exchange field as they facilitate epitaxy between the NiFe and NiMn layers. The application of an amorphous Ta nucleation layer and substrate biasing during NiFe deposition have been found to promote these structures. Fcc NiMn replicates the (111) texture through epitaxial growth on NiFe according to a cube on cube orientation relationship. Upon annealing, atomic ordering takes place in the NiMn layer and gives rise to an exchange biased field. However, a fully L10 ordered structure cannot be achieved at the NiMn/NiFe interface due to the stabilizing effect of fcc NiFe. Away from the interface, the transformation proceeds and the ordered tetragonal unit cell creates a lattice strain within the NiMn film. This strain is relieved by twinning within the NiMn grains of the film. The strength of the exchange field has been found to be closely associated with the density of twins and their proximity to the NiMn/NiFe interface.
A satellite based system for managing crisis scenarios: The E-SPONDER perspective (2010)

This paper presents the work that is currently performed in the E-SPONDER (FP7-242411) project. E-SPONDER is a project co-funded by the European Commission under its Security Program. E-SPONDER is a suite of real-time data-centric technologies that will provide information and communication support to first responders which act during normal and abnormal events (crises). It will investigate the use of interoperable communications that will facilitate the uninterruptible link between the first responders at the operations theatre and the crisis managers at the Emergency Operations Center. To achieve that, a novel architecture is introduced that brings satellite communications in the spotlight of effective first response work. The paper demonstrates the way satellite communications will be integrated to the E-SPONDER system in order to ensure always-on communications and data exchange.