gebhart/patrepeval huggingface dataset:
Design and Analysis of an Intentional Mistuning Experiment Reducing Flutter Susceptibility and Minimizing Forced Response of a Jet Engine Fan (2017)

Recent demands for a reduction of specific fuel consumption of jet engines have been opposed by increasing propulsive efficiency with higher bypass ratios and increased engine sizes. At the same time the challenge for the engine development is to design safe and efficient fan blades of high aspect ratios. Since the fan is the very first rotor stage, it experiences significant distortions in the incoming flow depending on the operating conditions. Flow distortions do not only lead to a performance and stall margin loss but also to remarkable low engine order (LEO) excitation responsible for forced vibrations of fundamental modes. Additionally, fans of jet engines typically suffer from stall flutter, which can be additionally amplified by reflections of acoustic pressure waves at the intake. Stall flutter appears before approaching the stall line on the fan’s characteristic and limits its stable operating range. Despite the fact that this “flutter bite” usually affects only a very narrow speed range, it reduces the overall margin of safe operation significantly. With increasing aspect ratios of ultra-high bypass ratio jet engines the flutter susceptibility will probably increase further and emphasizes the importance of considering aeromechanical analyses early in the design phase of future fans. This paper aims at proving that intentional mistuning is able to remove the flutter bite of modern jet engine fans without raising issues due to heavily increased forced vibrations induced by LEO excitation. Whereas intentional mistuning is an established technology in mitigating flutter, it is also known to amplify the forced response. However, recent investigations considering aeroelastic coupling revealed that under specific circumstances mistuning can also reduce the forced response due to engine order excitation. In order to allow a direct comparison and to limit costs as well as effort at the same time, the intentional mistuning is introduced in a non-destructive way by applying heavy paint to the blades. Its impact on the blade’s natural frequencies is estimated via finite element models with an additional paint layer. In parallel, this procedure is experimentally verified with painted fan blades in the laboratory. A validated SNM (subset of nominal system modes) representation of the fan is used as a computational model to characterize its mistuned vibration behavior. Its validation is done by comparing mistuned mode shape envelopes and frequencies of an experimental modal analysis at rest with those obtained by the updated computational model. In order to find a mistuning pattern minimizing the forced response of mode 1 and 2 at the same time and satisfying stability and imbalance constraints, a multi-objective optimization has been carried out. Finally, the beneficial properties of the optimized mistuning pattern are verified in a rig test of the painted rotor.
Voltage shifts and imprint in ferroelectric capacitors (1995)

Voltage offsets in the polarization-voltage characteristics of Pb(Zr,Ti)O3 capacitors can be induced by either thermal or optical processes. The thermally (optically) induced voltage shift occurs by heating (illuminating) the sample under remanence or a saturating bias. Generally speaking, the thermally induced voltage shifts are greater than those obtained optically; this is attributed to the role of oxygen vacancy-related defect dipoles throughout the film. We find that the inclusion of a dopant element that occupies a portion of the Ti(Zr) sites and has an oxidation state greater than +4 reduces the thermally induced voltage shifts observed in the capacitors. This may result because these particular dopants reduce the oxygen vacancy density and, hence, the defect-dipole contribution to the voltage shift.
[Clinical, diagnostic and therapeutic problems in the postthrombotic syndrome. Our experience]. (1990)

An analysis is presented, of the experience acquired in the II-nd Surgical Clinic of Cluj-Napoca in connection with 150 cases of postthrombotic syndrome followed and treated over the last 5 years (1983-1987). Considerations are made concerning terminology, and evaluation of diagnostic and therapeutic means applied. The post-thrombotic syndrome develops in a variable interval after the thrombophlebitis (months and even years). A series of factors prevent of enhance the development of the syndrome (98% diagnostic errors and therapeutic failures). Phlebography is mandatory in cases where surgery is considered. Noninvasive explorations (Doppler, plethysmography) limit the use of phlebography. The most efficient treatment is prophylaxis (consisting in the prophylaxis and the correct treatment of thromboembolic disease). The usual treatment is mainly medical and conservative (59.4%). Surgery is carried out in cases where the superficial, the communicating and the deep venous systems are involved.
Thermal Fatigue Life Estimation and Fracture Mechanics Studies of Multilayered MEMS Structures Using a Sub-Domain Approach (2012)

This paper is concerned with the application of a Physics of Failure (PoF) methodology to assessing the reliability of Micro-Electro-Mechanical-System (MEMS) switches. Numerical simulations, based on the finite element method (FEM) using a sub-domain approach, were performed to examine the damage onset (e.g. yielding) due to temperature variations and to simulated the crack propagation different kind of loading conditions and, in particular, thermal fatigue. In this work remeshing techniques were employed in order to understand the evolution of initial flaws due, for instance, to manufacturing processes or originated after thermal fatigue.
Enhancing Data Transmission Reliability with Multipath Multicast Rate Allocation (2011)

In this paper, a multipath routing scheme is pro- posed for data transmission in a packet-switched network to improve the reliability of data delivery to multicast destinations, and to reduce network congestion. A multi-objective optimization model is presented that utilizes FEC (Forward Error Correction) across multiple multicast trees for transmitting packets toward the destinations. This model assigns the transmission rates over multicast trees so that the probability of irrecoverable loss for each destination and also the link congestion are minimized. We propose a genetic algorithm based on SPEA (Strength Pareto Evolutionary Algorithm) in order to approximate Pareto optimal solutions of this rate allocation problem with a non- dominated solution set. Numerical results show that splitting data packets between multiple trees increases reliability and decreases network congestion when compared with the results obtained for transmitting data packets over a single tree. Index Terms—Forward Error Correction (FEC), load bal- ancing, multicast communication, multipath routing, Quality of Service
ESD reliability and protection schemes in SOI CMOS output buffers (1995)

The electrostatic discharge (ESD) protection capability of SOI CMOS output buffers has been studied with Human Body Model (HBM) stresses. Experimental results show that the ESD voltage sustained by SOI CMOS buffers is only about half the voltage sustained by the bulk NMOS buffers. ESD discharge current in a SOI CMOS buffer is found to be absorbed by the NMOSFET alone. Also, SOI circuits display more serious reliability problem in handling negative ESD discharge current during bi-directional stresses. Most of the methods developed for bulk technology to improve ESD performance have minimal effects on SOI. A new Through Oxide Buffer ESD protection scheme is proposed as an alternative for SOI ESD protection. In order to improve ESD reliability, ESD protection circuitries can be fabricated on the SOI substrate instead of the top silicon thin film, after selectively etching through the buried oxide. This scheme also allows ESD protection strategies developed for bulk technology to be directly transferred to SOI substrate.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
A New Slot-Count Selection Algorithm for RFID Protocol (2007)

EPCglobal RFID generation-2 (Gen-2) protocol [1] has been proposed for ultra-high frequency (UHF) passive tags and is being deployed. Gen-2 proposes a slotted random anti-collision algorithm, including an adaptive slot-count (Q) selection algorithm. The integer-valued parameter Q in Gen-2 plays a critical role in tag collision resolution. This adaptive algorithm dynamically adjusts value of Q based on the type of replies from tags. However, it modifies the value of Q the same way whether there is a "collided reply" or "no reply". This approach could lead to a slow tag identification speed, since it does not recognize the differences in duration between the "collided reply" and "no reply". This paper proposes a new slot-count selection algorithm which changes the parameter Q with different amounts depending on whether the reader receives a "collided reply" or there is "no reply" by a pre-specified waiting time. It is demonstrated, through analysis and simulations, that the new proposed algorithm achieves significantly faster tag identification speed compared to that of the existing Gen-2 adaptive Q algorithm.
Soft Condensed Matter (2002)

Abstract The physics of soft condensed matter is probably one of the most 'fashionable' areas in the physical sciences today. This book offers a coherent and clear introduction to the properties and behaviour of soft matter. It begins with a treatment of the general underlying principles: the relation of the structure and dynamics of solids and liquids to intermolecular forces, the thermodynamics and kinetics of phase transitions, and the principles of self-assembly. Then the specific properties of colloids, polymers, liquid crystals and self-assembling amphiphilic systems are treated within this framework. A concluding chapter illustrates how principles of soft matter physics can be used to understand properties of biological systems. The focus on the essentials and the straightforward approach make the book suitable for students with either a theoretical or an experimental bias. The level is appropriate for final year undergraduates and beginning graduate students in physics, chemistry, materials science, and chemical engineering.
Block Polymers Derived from Poly(ethylene Oxide) and Hydroxy-Terminated Polybutadiene (1979)

Abstract Block polymers of AB, BAB, and ABA type, derived from preformed poly(ethylene oxide) (PEO) of different molecular weight and hydroxy-terminated polybutadiene (HTPB) were prepared. Poly(ethylene oxide-b-butadiene) and poly(butadiene-b-ethylene oxide-b-butadiene) were prepared by reaction of PEO, which was previously endcapped with TDI, with HTPB at a 1:1 or 1:2 reactants molar ratio. Poly(ethylene-oxide-b-butadiene-b-ethylene oxide) were prepared by reaction of isocyanate-endcapped HTPB with PEO at a molar ratio of reactants of 2:1. High reaction yields were obtained. Correlation between tensile properties and water absorption with block polymer composition was found.
450 Mbit/s optical frequency-division-multiplexing transmission with an 11 GHz channel spacing (1985)

A 450 Mbit/s 13 km optical frequency-division-multiplexing transmission with an 11 GHz channel spacing was demonstrated at 1.5 μm wavelength to confirm the feasibility of a laser-diode frequency-stabilising circuit and a narrow-channel-spaced optical demultiplexer.
Fluorescence resonance energy transfer between two quantum dots with immunocomplexes of antigen and antibody as a bridge (2006)

In this study, 573 nm quantum dots (QDs)-rabbit IgG-goat anti-rabbit IgG-638 nm QDs immunocomplexes were prepared, utilizing antigen-antibody interaction. 573 nm-emitting QDs were conjugated to antigen (rabbit IgG) and 638 nm-emitting QDs were conjugated to antibody (goat anti-rabbit IgG) via electrostatic/hydrophilic self-assembly, respectively. The mutual affinity of the antigen and antibody brought two kinds of QDs close enough to result in fluorescence resonance energy transfer (FRET) between them; the luminescence emission of 573 nm QDs was quenched, while that of 638 nm QDs was enhanced. The luminescence emission of 573 nm QDs could be recovered when the immunocomplexes were exposed to the unlabelled rabbit IgG antigen. The FRET efficiency (E) and the distance between the donor and the acceptor were calculated.
Core Flood Study of a New Emulsified Acid with Reservoir Cores (2012)

Abstract The main objective of well stimulation has been to create wormholes or fractures in order to bypass the damaged zone and enhance the permeability in the near-wellbore area. Regular HCl was the main stimulation fluid. However, at high temperatures, both reaction and corrosion rates become very high and regular HCl loses its advantages. There are many alternatives for regular HCl; emulsified acid is one of the available alternatives for regular HCl. In the present work, an emulsified acid system was used formulated using a cationic surfactant. This system was tested using reservoir cores obtained from a carbonate reservoir. The core samples were analyzed using CAT scan to study the presences of vugs or channels, and to determine the presence of anhydrite. Small samples of the cores were analyzed using the SEM technique. A series of core flood tests were conducted using 15 wt% HCl emulsified acid systems formulated using 1.0 vol% emulsifier. The acid volume fraction was 0.7, and all experiments were performed at temperature of 220°F. The acid injection rate ranged from 1.0 to 10 cm3/min. After acid treatment is accomplished, the cores were CAT scanned to study the number and distribution of wormholes. Samples of the effluent fluid were collected during the core flooding experiment. These collected samples were analyzed using the ICP, to determine the calcium and magnesium concentrations. The CAT scan of the cores obtained from a carbonate reservoir showed a great heterogeneity. The static test for solubility of rocks in regular 15 wt% HCl, indicated that the rocks has a high solubility in acid and the need to use an effective retarded acid system. From the coreflood study, there is an optimum injection rate for an emulsified acid system when it was tested reservoir cores, and it was found to be in the range from 5 to 7 cm3/min. The emulsified acid system can be used effectively, with no face dissolution, at low and high injection rates. For high permeability cores, the final permeability enhancement (ratio of final to initial permeability) increased with increasing the injection rate.
Mercury uptake in various cationic forms of several zeolites (1967)

The sorption of mercury has been measured at temperatures above 200° in the sodium, lead, mercury, and silver ion-exchanged forms of the near-faujasite, zeolite X, and in the silver forms of zeolite A, chabazite, and gmelinite. In Na- and Pb-X the sorption of the vapour is very slight and obeys Henry's law, the isosteric heats being, respectively, –8·3 and –9·1 kcal. per g.-atom of mercury. Accordingly the sorption heats from liquid mercury are endothermic.In the mercury and silver zeolites on the other hand sorption occurred copiously. Over the initial stages in mercury-X, sorption followed Langmuir's isotherm with a heat of about –12 kcal. per g.-atom, and with reduction of some of the Hg++ to Hg2++. This stage was followed by further substantial uptake, to give a step-wise adsorption branch and a desorption branch which formed a closed hysteresis loop. The adsorption was associated with a sequence of specific colour changes.In the silver-X the copious sorption gave type IV isotherms in Brunauer's classification. The first stage appeared to be a reduction of Ag+ to Ag with formation of Hg++, but this was followed by an uptake of mercury in association with the silver atoms sufficient to fill the intracrystalline free volume of zeolite X. Desorption branches showed some hysteresis, associated with a small irreversible weight increase which increased with each sorption–desorption cycle. This was traced to a slow drift of silver atoms to the surface of the zeolite, yielding silver crystals. Zeolite A sorbed mercury to give a small hysteresis loop, adsorption but not desorption being a curve of type IV. Chabazite and gmelinite gave curves only of type I and, like the other silver zeolites, exhibited some irreversibility.
Advances of 3- to 10-W average-power diode-pumped lasers (1993)

Current results for diode pumped solid state lasers are driven by advances in diode laser technology. Diode arrays in the 10 - 20 watt range are now available in useful formats which allow coupling into side- and end-pumped laser configurations. Side-pumped designs have traditionally produced higher output power at the expense of mode quality. End-pumped devices, on the other hand, have shown high mode quality but have been limited in their output power or pulse energy. Results are given which demonstrate new end-pumped laser coupling and cavity configurations which allow both high mode quality and increased power output.
Rapid, microtubule-dependent fluctuations of the cell margin (1997)

Using data automatically acquired by microinterferometry from large numbers of chick fibroblasts, we have detected rapid microfluctuations in the rates of protrusion and retraction of the cell margin which were strongly suppressed by colcemid, nocodazole and taxol. Fluctuations in the rate of retraction of the margin were about twice as powerful as fluctuations in the rate of protrusion. High-frequency fluctuations were also apparent in the cell track and in measures of cell spreading, shape and speed. These rapid fluctuations were also all suppressed by colcemid and nocodazole, sometimes by doses insufficient to disrupt the majority of microtubules. Taxol on the other hand did not suppress fluctuations in direction of the cell track nor fluctuations in the spreading of the cells but it was very effective at suppressing variations in protrusion and retraction and in cell speed and shape. We discovered that much slower, larger-scale variations in protrusion, retraction, spreading, shape and speed resulted from the accumulation of these rapid, microtubule-dependent fluctuations of the cell margin. These large-scale variations in cell behaviour were also suppressed by the same drug treatments that were effective in suppressing the corresponding high-frequency fluctuations. We speculate that a function of microtubules is to enhance the fibroblast's responses to its environment by causing microfluctuations of the cell's margin which give rise to large-scale variations in cell behaviour.
UV-VIS spectra of small iron particles (1994)

UV-VIS absorption spectra of ultrafine iron particles obtained in microemulsions were measured from 290 nm up to 550 nm. There was observed the existence of three bands and a band shift towards a higher energy region by 0.1-0.2 eV compared with that of bulk iron. This energy shift can be interpreted in terms of a quantum size effect. The electron-hole effective mass is evaluated to be 0.20 times the mass of a bare electron.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Aspects Hindering the Development and Survival of Small and Medium-Sized Enterprises in Pakistan: Stability Perspective (2021)

This article intends to explore aspects that are hindering the development and survival of small and medium-sized enterprises (SMEs) in Pakistan. A survey was developed to collect statistics from 226 SME owners and staff in selected Punjab Provinces in Pakistan. Some statistical approaches accompanied the results of the survey to examine the elements hindering the development of SMEs in Pakistan. The results of the research indicate that the expected constraints, including lack of management knowledge, corruption, decaying infrastructure, absence of financial funds, and inadequate earnings are hindering SME development and survival in Pakistan. Considering the elements hindering the development will help legislators, federal and local concerns, NGOs, shareholders, policymakers, and others to create well-structured policies and plans that will aggressively promote the efficiency and stability of SMEs in Pakistan. The significance of this research derives from the reality that few studies have been conducted about the development and survival of SMEs in Pakistan with a stability perspective.
Spontaneous Calcium Oscillations Control c-fosTranscription via the Serum Response Element in Neuroendocrine Cells (2002)

In excitable cells the localization of Ca2+ signals plays a central role in the cellular response, especially in the control of gene transcription. To study the effect of localized Ca2+ signals on the transcriptional activation of the c-fos oncogene, we stably expressed various c-fos beta-lactamase reporter constructs in pituitary AtT20 cells. A significant, but heterogenous expression of c-fos beta-lactamase was observed in unstimulated cells, and a further increase was observed using KCl depolarization, epidermal growth factor (EGF), pituitary adenylate cyclase-activating polypeptide (PACAP), and serum. The KCl response was almost abolished by a nuclear Ca2+ clamp, indicating that a rise in nuclear Ca2+ is required. In contrast, the basal expression was not affected by the nuclear Ca2+ clamp, but it was strongly reduced by nifedipine, a specific antagonist of l-type Ca2+ channels. Spontaneous Ca2+ oscillations, blocked by nifedipine, were observed in the cytosol but did not propagate to the nucleus, suggesting that a rise in cytosolic Ca2+ is sufficient for basal c-fos expression. Inactivation of the c-fos promoter cAMP/Ca2+ response element (CRE) had no effect on basal or stimulated expression, whereas inactivation of the serum response element (SRE) had the same marked inhibitory effect as nifedipine. These experiments suggest that in AtT20 cells spontaneous Ca2+ oscillations maintain a basal c-fos transcription through the serum response element. Further induction of c-fos expression by depolarization requires a nuclear Ca2+ increase.
AIDS Vaccine Research: Promising Protein (1986)

Research results with a viral antigen have raised hopes for the development of a vaccine against acquired immunodeficiency syndrome (AIDS). The antigen a protein from the outer coat or envelope of the AIDS retrovirus triggered an immune response when injected into animals and the antibodies made by the animals neutralized AIDS virus in the test tube. So far antibody formation has been induced in goats rabbits mice and guinea pigs. Antibodies with at least a slight ability to neutralize the AIDS virus in vitro have been found in the blood of some AIDS patients and pre-AIDS patients. The next step is to induce antibody formation in chimpanzees who unlike the other animals tested are vulnerable to the AIDS virus. Even if gp120 is found to protect chimpanzees against AIDS potential questions remain. Of greatest concern is the variability of the virus. It is unclear whether an antigen that comes from 1 viral strain and confers immunity against it will give protection against another strain. Although gp120 is 1 of the most variable of the viral proteins there are stretches within it that remain unchanged throughout the different strains. If the conserved regions are important in producing neutralizing antibodies gp120 from any strain might elicit antibodies that recognize the protein of any other strain. The earliest possible testing of an AIDS vaccine would be in 1988. The current research is being conducted at Duke University and the National Cancer Institute in the US.