Academic literature on the topic 'QMA DMA'

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Journal articles on the topic "QMA DMA"

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Xu, Jiahui, Guichen Li, Ruiyang Bi, Haoyu Rong, and Changlun Sun. "Explanation on the Abnormal Behavior during the Nanoindentation Holding Stages by Amplifying Oscillation." Advances in Civil Engineering 2022 (January 18, 2022): 1–11. http://dx.doi.org/10.1155/2022/8886965.

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Recently, the holding states of nanoindentation experiments have been widely used to analyze the time-dependent deformations of various rocks, and the dynamic mechanical analysis (DMA) method seems to be more applicable than the quasi-static mechanical analysis (QMA) method when the influence of creep deformation on mechanical properties of rocks was analyzed. However, the former method causes an abnormal behavior during the creep holding stages that was not clearly interpreted.2 Consequently, in this study, by amplifying the oscillation of the DMA method, the mechanical mechanism of this phenomenon was explained. Experimental results confirm that the rheological deformation of rocks consists of the creep deformation (depth increasing) and the elastic aftereffect deformation (depth decreasing) during the creep time with small oscillation; once the elastic aftereffect deformation exceeds the creep deformation, the abnormal behavior can be observed. Besides, some other abnormal behaviors might be found for other rock materials when the DMA method with different oscillations is used, which illustrates the complexity and limitation of applying this method. Thus, the QMA method was recommended to investigate the above questions in future studies.
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Schweighardt, Attila, and Balázs Vehovszky. "Comparison of different methods for dynamic characterization of porous-elastic materials." INTER-NOISE and NOISE-CON Congress and Conference Proceedings 268, no. 4 (November 30, 2023): 4848–58. http://dx.doi.org/10.3397/in_2023_0688.

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Acoustical simulation of porous-elastic materials requires several properties to be characterized, one of them is the dynamic mechanical behavior of the structure. For this goal, quasi-static mechanical analysis (QMA) is the generally used method executed in the ca. 20-60 Hz frequency range, resulting constant (averaged) mechanical properties. Polymer-based materials, however, are well-known from their time- and frequency-dependent behavior. This implies the need for having frequency-dependent data in a wider frequency range, but the error induced by the fluid motion inside the pores increases with frequency. For that reason, dynamic mechanical analysis (DMA) together with frequency-temperature superposition method was chosen to analyze the possibility of extending the evaluable frequency range. Different measurement setups and strategies were tested and evaluated to minimize the errors coming from machine resonances and other influencing factors, and results were compared to those obtained from the classical QMA measurements. It was finally proven, that with thoroughly chosen technique, DMA can give high quality results for porous-elastic materials as well, in a remarkably wide frequency range.
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Lin, Lu Bin, Qing Yun Yu, Zhuo Qun Gu, Xiao Ze Jiang, and Mei Fang Zhu. "Reduction-Degradable Shell Cross-Linked Micelle with pH-Responsive Cores Prepared via Click Chemistry." Materials Science Forum 848 (March 2016): 527–31. http://dx.doi.org/10.4028/www.scientific.net/msf.848.527.

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A well-defined poly [(ethylene glycol)-block-2-(dimethylamino) ethyl methacrylate-block-2-(diethylamino) methacrylate] (PEG-b-DMA-b-DEA) triblock copolymer was synthesized via atom transfer radical polymerization (ATRP) by successively polymerization of DMA and DEA monomers using a PEG-based macroinitiator, and obtained copolymer was then converted to be PEG-b-P(DMA-co-QDMA)-b-PDEA copolymer with “clickable” moieties in the middle block by the quaternization with propargyl bromide. Those copolymers prepared were characterized by proton Nuclear Magnetic Resonance (1H NMR) and Gel Permeation Chromatography (GPC), and its self-assembly behavior and subsequently fixation with bis-(azidoethyl) disulfide via click chemistry resulting reduction-sensitive shell-cross-linked (SCL) micelle in purely aqueous solution were investigated by Transmission Electron Microscopy (TEM) and Dynamic Light Scattering (DLS). The results show the micellar structure could be effectively cross-linked via click chemistry and also be dissociated at reduction condition, which may realize it's potential application as novel drug delivery carriers.
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Turgeman Dahan, Noy, Jean-Jacques Vatine, Irit Weissman-Fogel, Hana Karpin, Sharon Shmuely, and Tami Bar-Shalita. "Quantitative Dynamic Allodynograph—A Standardized Measure for Testing Dynamic Mechanical Allodynia in Chronic Limb Pain." Sensors 23, no. 18 (September 18, 2023): 7949. http://dx.doi.org/10.3390/s23187949.

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Background: Dynamic mechanical allodynia (DMA) is both a symptom and a central sensitization sign, yet no standardized method for quantifying the DMA area has been reported. This study aimed to establish psychometric properties for Quantitative Dynamic Allodynography (QDA), a newly developed protocol measuring the DMA area as a percentage of the body surface. Methods: Seventy-eight patients aged 18–65 diagnosed with chronic complex regional pain syndrome (CRPS) participated in this study. Test–retest reliability was conducted twice, one week apart (N = 20), and inter-rater (N = 3) reliability was conducted on 10 participants. Disease severity (CRPS Severity Score, CSS), pain intensity (VAS), and quality of life (SF-36) measures were utilized to test construct validity. Results: High inter-rater reliability (intraclass correlation coefficient (ICC) = 0.96, p < 0.001) and test–retest reliability (r = 0.98, p < 0.001) were found. Furthermore, the QDA score was found to be correlated with the CSS (r = 0.47, p < 0.001), VAS (r = 0.37, p < 0.001), and the SF-36 physical health total (r = −0.47, p < 0.001) scores. Conclusion: The QDA is the first developed reliable and valid protocol for measuring DMA in a clinical setting and may be used as a diagnostic and prognostic measure in clinics and in research, advancing the pain precision medicine approach.
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Zhu, Shu Yu, Zhong Li Niu, Xiao Ting Zhang, Dan Yue Wang, Jia Ming Xu, Bin Sun, Mei Fang Zhu, and Xiao Ze Jiang. "Doxorubicin Loading Capacity of Shell Cross-Linked Micelles with pH-Responsive Core as Anticancer Drug Delivery Nanocarriers." Materials Science Forum 898 (June 2017): 2366–72. http://dx.doi.org/10.4028/www.scientific.net/msf.898.2366.

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Detailed studies were performed to probe the effects of the cross-linking layer microstructure of pH-responsive shell cross-linked (SCL) micelles on the loading capacity of doxorubicin (DOX). Well-defined poly [(ethylene glycol)-block-2-(dimethylamino) ethyl methacrylate-block-2-(diethylamino) methacrylate] (PEG-b-P(DMA- co-QDMA)-b-PDEA) copolymer with “clickable” moieties in the middle block by the quaternization with propargyl bromide dissolved molecularly in acidic solution; micellization occurred at alkaline solution to form three-layer “onionlike” micelles constituting PDEA cores, P(DMA-co-QDMA) inner shells, and PEG coronas. Two types of cross-linker bearing azide group: 1,6-bisazidehexane and bis-(azidoethyl) disulfide were utilized to prepare the SCL micelles with different cross-linking layer microstructure via click chemistry at basic aqueous media. The results showed that two types of SCL micelles possessed excellent stability. In neutral solution, these SCL micelles still maintained structural integrity, and the average hydrodynamic diameter of SCL micelles 1 and SCL micelles 2 increased to 80 nm and 90 nm, respectively. In the acidic solution, due to the complete protonated of the PDEA core, the sizes of the two types of SCL micelles increased to 95 nm and 110 nm, respectively, which were favorable for the diffusion of the encapsulated drug in the core. Moreover, the cross-linking degree had no effect on the size of SCL micelles. The loading efficiency and loading content of the SCL micelles were significantly better than those of the uncross-linked micelles, and loading capacity did not vary with degree of cross-linking. However, the SCL micelles 1 demonstrated better loading capacity. This study could be a guidance for the future research on the effects of the cross-linking layer microstructure on controlled doxorubicin release.
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Zhu, Kai, Chongshi Gu, Jianchun Qiu, Wanxin Liu, Chunhui Fang, and Bo Li. "Determining the Optimal Placement of Sensors on a Concrete Arch Dam Using a Quantum Genetic Algorithm." Journal of Sensors 2016 (2016): 1–10. http://dx.doi.org/10.1155/2016/2567305.

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Structural modal identification has become increasingly important in health monitoring, fault diagnosis, vibration control, and dynamic analysis of engineering structures in recent years. Based on an analysis of traditional optimization algorithms, this paper proposes a novel sensor optimization criterion that combines the effective independence (EFI) method with the modal strain energy (MSE) method. Considering the complex structure and enormous degrees of freedom (DOFs) of modern concrete arch dam, a quantum genetic algorithm (QGA) is used to optimize the corresponding sensor network on the upstream surface of a dam. Finally, this study uses a specific concrete arch dam as an example and determines the optimal sensor placement using the proposed method. By comparing the results with the traditional optimization methods, the proposed method is shown to maximize the spatial intersection angle among the modal vectors of sensor network and can effectively resist ambient perturbations, which will make the identified modal parameters more precise.
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Fitriansyah, Sani Nurlaela, Rika Hartati, and Irda Fidrianny. "Effect of Different Solvent on Phytochemical Content, Tyrosinase Inhibition and Antioxidant Activities of Campolay (Pouteria campechiana kunth. [Baehni.])." Open Access Macedonian Journal of Medical Sciences 10, A (January 18, 2022): 158–63. http://dx.doi.org/10.3889/oamjms.2022.8204.

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BACKGROUND: Pouteria campechiana leaves are reported to have phenol and flavonoid compounds. Phenolic and flavonoid compounds can act as tyrosinase inhibitor and antioxidant. AIM: The purpose of this study was to compare phytochemical content, tyrosinase inhibition, antioxidant activities, and determine of marker compound from P. campechiana leaves extract with different polarities solvent. METHODS: In addition, the content of marker compound from P. campechaina leaves extract was determined by HPLC. RESULTS: The highest total phenolic content (TPC) 7.83 GAE/100 g extract, IC50 of tyrosinase 171.512 ± 1.352 and IC50 of DPPH 0.968 ± 0.008 was given by ethanolic extract (DE). Meanwhile ethyl acetate extract (DEA) had the highest of total flavonoid content 2.544 ± 0.554 QEA/100 g extract. The TPC correlated with tyrosinase inhibitory activity and antioxidant activity. CONCLUSION: Quercitrin was as marker compound from P. campechiana leaves extract, and quercitrin content in the DEA of P. campechiana leaves was 3.539%, while in the DE was 0.153%.
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Zhu, Kai, Chongshi Gu, Jianchun Qiu, and Hao Li. "The Analysis of the Concrete Gravity Dam’s Foundation Uplift Pressure under the Function of Typhoon." Mathematical Problems in Engineering 2016 (2016): 1–9. http://dx.doi.org/10.1155/2016/2834192.

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How to evaluate the seepage safety status of the concrete gravity dam under the function of short-period heavy rainfall and the possible historical extreme reservoir water level during typhoon is an important issue considering the dam safety-monitoring. Based on analysis of the monitoring series of the foundation uplift pressure, this paper assumed the influential process of antecedent reservoir water level and rainfall as a process of normal distribution and introduced the mutation factor to reflect the uprush feature of uplift pressure under the function of high-influential typhoon. Moreover, the corresponding hysteresis days and influential days of the model are optimized with quantum genetic algorithm (QGA) to raise the fitting and prediction accuracy. It is verified that the new statistical model for fitting can obtain higher multiple correlation coefficient (0.972) compared with the traditional statistical model (0.925) and could also perfectly predict the uprush feature of the pressure during the typhoon, which is of certain theoretical and practical application value in the future.
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Schneider, Bruna Celestino, Janaína Vieira dos Santos Motta, Ludmila Correa Muniz, Renata Moraes Bielemann, Samanta Winck Madruga, Silvana Paiva Orlandi, Denise Petrucci Gigante, and Maria Cecília Formoso Assunção. "Desenho de um questionário de frequência alimentar digital autoaplicado para avaliar o consumo alimentar de adolescentes e adultos jovens: coortes de nascimentos de Pelotas, Rio Grande do Sul." Revista Brasileira de Epidemiologia 19, no. 2 (June 2016): 419–32. http://dx.doi.org/10.1590/1980-5497201600020017.

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RESUMO: Objetivo: Artigo metodológico com o objetivo de descrever a construção de um questionário de frequência alimentar (QFA) digital autoaplicado, desenvolvido para as coortes de nascimentos de Pelotas de 1982 e 1993. Métodos: O instrumento foi criado com base em QFAs anteriormente utilizados nas duas coortes em acompanhamentos nos anos de 2004 e 2008. O QFA foi elaborado incluindo 88 alimentos e/ou preparações cujas frequências foram agrupadas em categorias desde o valor mínimo de consumo de nunca ou < 1 vez/mês até o máximo de ≥ 5 vezes/dia. As opções fechadas relativas à porção foram construídas considerando recordatórios de 24 horas (R24Hs) anteriormente aplicados à subamostra da coorte de 1993. Três alternativas de porção foram construídas: igual, menos ou mais. A porção igual foi descrita com base no percentil 50 do consumo de cada alimento, obtido a partir das distribuições das porções constantes nos R24H. Fotos das porções relativas ao percentil 50 de cada alimento foram também incluídas ao formato do programa. Resultados: Esse QFA digital incluiu alimentos e preparações que atendem aos objetivos das pesquisas atuais. A aparência do programa foi atrativa à equipe de trabalho e também aos participantes do estudo. O tempo médio de aplicação de 12 minutos e a facilidade de preenchimento possibilitaram que vários participantes respondessem às questões ao mesmo tempo. Além disso, o instrumento dispensou a necessidade de entrevistador e a dupla entrada de dados em programa específico. Conclusão: Recomenda-se o uso dessa mesma estratégia em outros estudos, adaptando-a aos diferentes contextos e situações.
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Abd-Al Wahhab, Iman, Sarmad Nory Gany, and Hussein Abdul Kadhim. "Assessment of RBCs membrane protective activity of citicoline and eicosapentanoic- decosahexanoic acid in osmotic fragility model." AL-QADISIYAH MEDICAL JOURNAL 10, no. 18 (July 26, 2017): 118–21. http://dx.doi.org/10.28922/qmj.2014.10.18.118-121.

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Different organic compounds possess a good membranes stabilizing effects that protect cells like erythrocytes from strains exerted by change in medium osmolarity . These changes in tonicity could predispose RBCs for hemolysis . This disorder could be assessed by osmotic fragility test . From those compounds that widen osmotic fragility test values are citicoline (membrane phospholipids precursor) and polyunsaturated fatty acids EPA-DHA. Assessment of these compounds on osmotic fragility test revealed that both of citicoline and EPA-DHA will protect RBCs from hemolysis for a wider range than values of the control blank. Although these effects were statistically not significant on considering statistical correlation test, however, the differences were important on considering t test for the range of saline concentration between 0.4-0.5 at P<0.05 . From the overall results, both citicoline and pufa induced a significant change in statbility of RBCs membrane upon exposure of osmotic effects in the saline concentration between 0.4-0.5. Further evaluation of citicoline and EPA- DHA effects may be necessary before recommending the use these compounds in protection against hemolytic diseases.
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Dissertations / Theses on the topic "QMA DMA"

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Wilkinson, Alexandre. "Characterization and modelling of porous automotive engine encapsulation materials for external acoustics." Electronic Thesis or Diss., Compiègne, 2024. http://www.theses.fr/2024COMP2806.

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L’encapsulage de moteurs automobiles par des écrans poreux est une solution technologique qui sert à réduire le bruit qu’ils rayonnent dans l’environnement. L’utilisation actuelle de ces écrans repose principalement sur leur capacité à absorber le son lorsqu’ils sont placés à distance du moteur dans son compartiment, mais une nouvelle configuration qui les place directement au contact du moteur apporte plusieurs avantages. Ceci permet notamment un gain de masse et de matière première, mais modifie significativement leur comportement acoustique. En particulier, la température du moteur, la précontrainte appliquée, et la proportion de contact entre le moteur et l’écran pilotent le comportement acoustique du système. Cette thèse a pour objectif de caractériser les matériaux poreux d’encapsulage et d’étudier leur comportement acoustique dans leur nouvelle configuration au contact d’une surface rayonnante représentant le moteur. Ce travail s’inscrit dans un projet industriel appeléSEMPAE (Simulation de l’Encapsulage Moteur Pour l’Acoustique Externe, de 2020 à 2024), mené en collaboration entre le groupe Trèves, équipementier automobile, le groupe Renault, constructeur automobile, le groupe ESI, éditeur de logiciel, et le laboratoire de recherche Roberval de l’UTC. Dans un premier temps, plusieurs matériaux d’encapsulage, dont des mousses polymères et des matériaux fibreux, sont caractérisés pour obtenir leurs propriétés et alimenter une modélisation poroélastique. Les diverses méthodes de caractérisation sont comparées entre elles et appliquées. Une attention particulière est portée à la caractérisation des propriétés mécaniques, pour lesquelles il reste à ce jour beaucoup d’incertitudes. Ensuite, la raideur d’une mousse en mélamine comprimée par une surface rigide est étudiée. Sa relaxation au cours du temps est observée et modélisée, mettant en lumière la rhéologie complexe des matériaux poreux. Sa non-linéarité en fonction de la déformation est prise en compte, permettant de comprendre l’interaction entre la non-linéarité intrinsèque du matériau et la non-linéarité due à la forme d’un échantillon à géométrie pyramidale. Puisque la raideur de compression d’une aspérité composée d’un matériau poreux peut être modélisée, la raideur de contact d’un matériau poreux à surface rugueuse peut être prédite.La dernière partie porte sur la réduction de la puissance acoustique rayonnée par une plaque recouverte d’un écran constitué d’une couche poreuse et d’une masse lourde. Le comportement masse-ressort de l’écran permet une réduction significative de la puissance rayonnée au-delà de la résonance du système. L’expérience montre qu’en réduisant la surface de contact entre l’écran et la plaque, la résonance se déplace vers les basses fréquences, améliorant donc l’isolation acoustique de l’écran. Le contact partiel est créé expérimentalement en rainurant les écrans et peut être modélisé par la méthode des matrices de transfert en parallèle
The encapsulation of car engines by porous screens is a technology that reduces the noise they radiate into their environment. Currently, their use relies mostly on their ability to absorb sound when placed inside the engine compartment, at a distance from the engine, but a new configuration that positions them directly in contact with the engine offers several advantages. Notably, this allows a reduction in mass and raw materials needed, but significantly alters their acoustic behaviour. In particular, the engine temperature, applied preload, and the amount of contact between the engine and the screen influence the acoustic behaviour of the system. This thesis aims to characterize the porous encapsulation materials and study their acoustic behaviour in their new configuration, in contact with a radiating surface representing the engine. This work is part of an industrial project called SEMPAE (Simulation of engine encapsulation for external acoustics, from 2020 to 2024), which is a collaboration between Trèves Group, an automotive equipment supplier, Renault Group, anautomotive manufacturer, ESI Group, a software publisher, and the Roberval research laboratory at UTC. First, various encapsulation materials, including polymer foams and fibrous materials, are characterized to obtain their properties that serve as input for poroelastic models. Various characterization methods are compared and applied. Special attention is given to the characterization of mechanical properties, for which there are still many uncertainties. Next, the stiffness of melamine foam compressed against a rigid surface is studied. Its relaxation over time is observed and modelled, highlighting the complex rheology of porous materials. Its nonlinearity as a function of strain is accounted for, revealing the interaction between the intrinsic nonlinearity of the material and the shape nonlinearity of a sample with a pyramidal geometry. Since the compression stiffness of an asperity made from a porous material can be modelled, the contact stiffness of a porous material with a rough surface can be predicted. Finally, the reduction of the acoustic power radiated by a plate covered with a screen consisting of a porous layer and a heavy sheet is studied. The mass-spring behaviour of the screen significantly reduces the radiated power beyond the resonance of the system. Experimental results reveal that by reducing the contact ratio between the screen and the plate, the resonance is shifted towards lower frequencies, which improves the acoustic insulation of the covering. Partial contact is created experimentally by cutting grooves into the screens, and is modelled using the parallel transfer matrix method
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Bag, Firat. "Numerical Simulation Of The Cinarcik Dam Failure On The Orhaneli River." Master's thesis, METU, 2005. http://etd.lib.metu.edu.tr/upload/12605843/index.pdf.

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This thesis analyzes the probable outcome of the fictitious failure of a dam under a set of pre-defined scenarios, within the framework of a case study, the case subject being the Cinarcik Dam located within Bursa Province of Turkey. The failure of the dam is not analyzed neither structural nor hydraulic-wise but is assumed to be triggered when certain critical criteria are exceeded. Hence, the analyses focus on the aftermath of the failure and strive to anticipate the level of inundation downstream of the dam itself. For the purpose of the analyses, the FLDWAV software developed by the National Weather Service of USA is used to spatially and temporally predict the flow profiles, water surface elevations and discharges occurring downstream of the Ç
inarcik Dam under the defined set of scenarios. Based on these analyses, indicative inundation maps and settlements under risk will be identified, and the thesis study will further address some available pre-event measures that may be taken in advance.
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Cetinkaya, Mehmet Akin. "Balkusan Dam And Hepp: Investigation Of Better Alternatives To Eiei Formulation." Master's thesis, METU, 2013. http://etd.lib.metu.edu.tr/upload/12615522/index.pdf.

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Due to the economic and social growth of Turkey, there is a rapid increase in energy demand. Turkey does not have sufficient natural gas and petroleum reserves
however, it has large hydropower potential. Hydropower is the most widely used form of renewable energy. To generate electricity between elevations 1500 m and 450 m on Balkusan Creek, General Directorate of Electrical Power Resources Survey and Development Administration (EIEI) conducted a feasibility study for a hydroelectric power plant (HEPP) composed of a rock-fill dam in 1999. In 2009, this formulation was not only revised but also constructed by Hidromark Company. The Hidromark-formulation consists of a roller compacted concrete dam and two diversion weirs. The aim of this study is to find a more beneficial alternative to the previous formulations. In order to avoid dam body and expropriation costs the Alternative-formulation composed of a run-of-river HEPP is developed. In the economic analysis, HEPPs are assumed to have two equal sized turbines and net benefits of different formulations are compared. Additionally, energy generation calculations are carried out for two turbines with different installed capacities only for the Alternative-formulation in order to investigate impact of turbine size on energy generation.
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Doluweera, D. G. Sumith Pradeepa. "Effect of Weak Inhomogeneities in High Temperature Superconductivity." University of Cincinnati / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1227215152.

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D'Alberto, Jacopo. "Study of a 2D Bose-Fermi mixture with quantum Monte Carlo methods." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021. http://amslaurea.unibo.it/24393/.

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Ultracold gases are an exceptionally versatile platform to test novel physical concepts. Thanks to the development of new experimental techniques, they have greatly advanced our understanding of the physics of many-body systems and allowed precision measurements of fundamental constants. Bose-Fermi mixtures can then be introduced in this context. This novel quantum many-body system is essentially an ultracold gas made up by both bosons and fermions, where tunable attractive or repulsive interactions between the components can be introduced. At T = 0 and for weak interactions the bosons condense while the fermions behave as a Fermi liquid. In particular, a recent system of interest is given by two-dimensional Bose-Fermi mixtures with both Bose-Fermi and Bose-Bose repulsive interactions. In the present work, a Quantum Monte Carlo study is conducted, for a fixed value of boson concentration, at zero-temperature from the weak to the strong Bose-Fermi coupling limit. Variational Monte Carlo and Fixed-Node Diffusion Monte Carlo are applied using an optimized Jastrow-Slater wavefunction, extending previous methodology developed for the three-dimensional case. The results are then compared with perturbative predictions, showing very good agreement in the weak coupling region. Variational Monte Carlo agrees with the analytic predictions only for extremely weak coupling, while Diffusion Monte Carlo proves necessary to recover good agreement over the whole perturbative regime. For stronger couplings, our simulations indicate the tendency of the mixture to form bosonic clusters. This finding would definitively deserve further investigation, which is postponed to future works.
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Niu, Yi Shuai. "Programmation DC et DCA en optimisation combinatoire et optimisation polynomiale via les techniques de SDP : codes et simulations numériques." Phd thesis, INSA de Rouen, 2010. http://tel.archives-ouvertes.fr/tel-00557911.

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L'objectif de cette thèse porte sur des recherches théoriques et algorithmiques d'optimisation locale et globale via les techniques de programmation DC & DCA, Séparation et Evaluation (SE) ainsi que les techniques de relaxation DC/SDP, pour résoudre plusieurs types de problèmes d'optimisation non convexe (notamment en Optimisation Combinatoire et Optimisation Polynomiale). La thèse comporte quatre parties :La première partie présente les outils fondamentaux et les techniques essentielles en programmation DC & l'Algorithme DC (DCA), ainsi que les techniques de relaxation SDP, et les méthodes de séparation et évaluation (SE).Dans la deuxième partie, nous nous intéressons à la résolution de problèmes de programmation quadratique et linéaire mixte en variables entières. Nous proposons de nouvelles approches locales et globales basées sur DCA, SE et SDP. L'implémentation de logiciel et des simulations numériques sont aussi étudiées.La troisième partie explore des approches de la programmation DC & DCA en les combinant aux techniques SE et SDP pour la résolution locale et globale de programmes polynomiaux. Le programme polynomial avec des fonctions polynomiales homogènes et son application à la gestion de portefeuille avec moments d'ordre supérieur en optimisation financière ont été discutés de manière approfondie dans cette partie.Enfin, nous étudions dans la dernière partie un programme d'optimisation sous contraintes de type matrices semi-définies via nos approches de la programmation DC. Nous nous consacrons à la résolution du problème de réalisabilité des contraintes BMI et QMI en contrôle optimal.L'ensemble de ces travaux a été implémenté avec MATLAB, C/C++ ... nous permettant de confirmer l'utilisation pratique et d'enrichir nos travaux de recherche.
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Iglhaut, Daniel Linß Gerhard. "Abgleich und Optimierung der bestehenden QM-Prozesse eines INA-Standorts in China mit den Soll-QM-Prozessen der Schaeffler Gruppe auf Basis VDA 6.3 /." 2006. http://www.gbv.de/dms/ilmenau/abs/51204810Xiglha.txt.

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Books on the topic "QMA DMA"

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Catherine, Plaisant, ed. Designing the user interface: Strategies for effective human-computer interaction. 4th ed. Boston: Pearson/Addison Wesley, 2005.

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Tafolla. El Dia Qua El Ermadillo Vio Su Sombra. Houghton Mifflin School, 1992.

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Figueiredo, Carla Pedrosa de, Isabel Lausanne Fontgalland, and César Martins De Oliveira. Direito, economia e sociedade. Editora Amplla, 2022. http://dx.doi.org/10.51859/amplla.des310.1122-0.

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O Direito, a Economia e a Sociedade seguem a ideia de interdisciplinaridade que permitirá ao leitor passear pelas ciências jurídicas, econômicas e sociais com vistas à compreender em cada capítulo instalado, uma visão de mundo acerca das mais variadas temáticas abordadas que alçam o indivíduo, na cruciante verdade. O interesse é condição “sine qua non” para que o leitor vise ampliar seus conhecimentos na seara do direito penal e processual penal, ao ponto de despertar a razão da ciência do Direito, percambiando deveras com a Economia no sentido de compreender quão emergente são as necessidades humanas as quais se encontram pautadas na garantia de direitos fundamentais e essenciais que ensejam a qualidade de vida de todos os membros do tecido social sem distinção. O diálogo científico em abordagens multidisciplinares apoia um desejo de arcabouço cientifico que remete ao leitor, visões de mundo que despertarão o desejo em conhecer as ciências afins que dragam um olhar holístico e realístico do contexto jurídico, social e ético.
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Hibbert, D. Brynn. Quality Assurance in the Analytical Chemistry Laboratory. Oxford University Press, 2007. http://dx.doi.org/10.1093/oso/9780195162127.001.0001.

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Analytical chemical results touch everyones lives can we eat the food? do I have a disease? did the defendant leave his DNA at the crime scene? should I invest in that gold mine? When a chemist measures something how do we know that the result is appropriate? What is fit for purpose in the context of analytical chemistry? Many manufacturing and service companies have embraced traditional statistical approaches to quality assurance, and these have been adopted by analytical chemistry laboratories. However the right chemical answer is never known, so there is not a direct parallel with the manufacture of ball bearings which can be measured and assessed. The customer of the analytical services relies on the quality assurance and quality control procedures adopted by the laboratory. It is the totality of the QA effort, perhaps first brought together in this text, that gives the customer confidence in the result. QA in the Analytical Chemistry Laboratory takes the reader through all aspects of QA, from the statistical basics and quality control tools to becoming accredited to international standards. The latest understanding of concepts such as measurement uncertainty and metrological traceability are explained for a working chemist or her client. How to design experiments to optimize an analytical process is included, together with the necessary statistics to analyze the results. All numerical manipulation and examples are given as Microsoft Excel spreadsheets that can be implemented on any personal computer. Different kinds of interlaboratory studies are explained, and how a laboratory is judged in proficiency testing schemes is described. Accreditation to ISO 17025 or OECD GLP is nearly obligatory for laboratories of any pretension to quality. Here the reader will find an introduction to the requirements and philosophy of accreditation. Whether completing a degree course in chemistry or working in a busy analytical laboratory, this book is a single source for an introduction into quality assurance.
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Designing the user interface: Strategies for effective human-computer-interaction. 3rd ed. Reading, Mass: Addison Wesley Longman, 1998.

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Designing the User Interface: Strategies for Effective Human-Computer Interaction. Pearson Higher Education & Professional Group, 2017.

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Designing the user interface: Strategies for effective human-computer interaction. Reading, Mass: Addison-Wesley, 1987.

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Designing the User Interface: Strategies for Effective Human-Computer Interaction. Pearson, 2016.

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Book chapters on the topic "QMA DMA"

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Valaei, Naser, Sajad Rezaei, Ree C. Ho, and Fevzi Okumus. "Beyond Structural Equation Modelling in Tourism Research: Fuzzy Set/Qualitative Comparative Analysis (fs/QCA) and Data Envelopment Analysis (DEA)." In Quantitative Tourism Research in Asia, 297–309. Singapore: Springer Singapore, 2018. http://dx.doi.org/10.1007/978-981-13-2463-5_14.

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Barros, Ana Tereza Duarte Lima de. "A ARMADILHA DA DEMOCRACIA DIRETA: UMA ANÁLISE QUALITATIVA DOS PODERES LEGISLATIVOS DO PRESIDENTE NA AMÉRICA DO SUL." In Ciências Humanas, Política e Sociedade, 125–36. Bookerfield Editora, 2021. http://dx.doi.org/10.53268/bkf21060309.

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Como instrumentos da democracia direta estariam associados a um menor nível de democracia? Venezuela, Bolívia e Equador promulgaram novas constituições que previram a ampla incorporação de instrumentos da democracia direta. O presente trabalho propõe que o referendo, quando convocado pelo presidente, serve para que o líder possa apelar diretamente às massas, sem qualquer intermediação legislativa, uma das principais características do populismo. Através da ferramenta Qualitative Comparative Analysis – QCA é feita uma análise qualitativa dos poderes legislativos do presidente na América do Sul. Conclui-se que o poder presidencial de convocar referendos está associado a um menor nível democrático. Dia 30 de novembro de 2008, utilizando-se do poder de referendo, o então presidente da Venezuela Hugo Chávez, convocou os cidadãos para decidirem a respeito da possibilidade de reeleição por tempo indefinido para o cargo de chefe do Executivo. Dia 15 de fevereiro de 2009, com 54,86% dos votos a favor e 45,1% contra, Chávez conseguiu aprovar a reforma constitucional que habilitou a reeleição de maneira indefinida.
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Rather, Ishfaq Ahmad, and Rashid Ali. "Recent Extensions of IDA-based Sensing Protocols." In Indicator Displacement Assays (IDAs): An Innovative Molecular Sensing Approach, 119–42. BENTHAM SCIENCE PUBLISHERS, 2024. http://dx.doi.org/10.2174/9789815165913124010007.

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With the advancement of supramolecular chemistry in the realm of sensing, researchers across the globe have developed various evolutionary extensions of IDAs from time to time. These comprise enantioselective indicator displacement assays (eIDAs), intramolecular indicator displacement assays (I-IDAs), indicator catalyst displacement assays (ICDA), reaction-based indicator displacement assays (R-IDAs), mechanically controlled indicator displacement assays (MC-IDAs), allosteric indicator displacement assays (A-IDAs), catalytic chemosensing assay (CCA), dimer dye assembly assay (DDA), and quencher displacement assay (QDA). All these evolutionary extensions of IDAs have been discussed in detail from concept to applications along with the possible future outcomes. The authors are of the viewpoint that this chapter will develop a better understanding of the researchers worldwide in the context of the advancement of IDAs.&nbsp;<br>
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"Quality Control." In DNA Fingerprinting, edited by Lorne t. Kirby. Oxford University Press, 1993. http://dx.doi.org/10.1093/oso/9780716770015.003.0012.

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Quality control (QC) is one aspect of quality assurance (QA). Quality assurance also includes (1) periodic laboratory audits by external specialists, (2) keeping upto-date clearly-written protocols, (3) preparation of QA reports, (4) troubleshooting, (5) equipment maintenance and calibration, (6) methodology development, (7) personnel training, (8) continuing education, and (9) laboratory safety. To be assured of ongoing quality performance, laboratory accreditation is mandatory. The above aspects have been discussed throughout this text; however, because DMA profiling often involves legal considerations, details of QC are presented in this chapter. An extremely important report, Guidelines for a Quality Assurance Program for DNA Restriction Fragment Length Polymorphism Analysis, prepared by the Quality Assurance Subcommittee of TWGDAM, is included in Appendix I (Mudd 1989). Quality control, narrowly defined, is directly concerned with the accuracy and precision of laboratory results for specimens of verified origin. Implicit in this definition is assurance that correct and accurate population allele frequencies are used in probability calculations. The expert witness representing the laboratory must ensure that (1) the correct specimen is analyzed, (2) the DNA is not significantly degraded, (3) the specimens are not significantly contaminated with extraneous DNA, (4) the analysis procedure is well-controlled, (5) result interpretation is correct, and (6) no deviations from the authorized laboratory protocol have occurred. The expert witness in DNA profiling should be a meticulous analyst with a solid grasp of genetic and biochemical principles combined with considerable experience in recombinant DNA processes. A reasonable understanding of the concepts and application of statistical techniques, especially probability, is a definite asset. The ability to articulate the results of an analysis and to respond under cross examination to in-depth questions concerning principles, techniques, and chain of custody is mandatory. (See Wetli 1989 for a general overview on appearing as an expert witness.) A set of objective QC criteria must be established and followed to ensure that neither false negative nor false positive DNA profile match results are released from a service laboratory.
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Gowricharn, Ruben. "Leefcultuur en burgerschap: De Nederlandse Hindostanen als casus." In Geleefd Burgerschap: Van eenheidsdwang naar ruimte voor verschil en vitaliteit, 28–46. Uitgeverij SWP, 2012. http://dx.doi.org/10.36254/978-90-8850-334-4.03.

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In de herfst van 1996 werd Nederland opgeschrikt door een schoolincident. Het was diwali, een Hindoefeest waarbij stukjes watten in aardekommetjes (dia’s genaamd) gevuld met ghee worden aangestoken. Qua symboliek is het diwalifeest, waarin de overwinning van het licht (het goede) op de duisternis (het kwade) wordt gevierd, vergelijkbaar met het kerstfeest. Kinderen van een basisschool hadden zich in een schemerige klas om een lichtpuntje in een dia verzameld, terwijl een Hindoe leerling uitleg gaf hoe het feest thuis werd gevierd en wat het allemaal voor hen betekende. Een bestuurslid van de school had moeite met wat hij noemde ‘de verering van geesten’. Hij eiste een verbod tegen de viering van het feest en maatregelen tegen de directie. Hij kreeg niet het hele bestuur mee. Ook het personeel van de school verzette zich. Het incident escaleerde tot een rel van nationale proporties en eindigde in het aftreden van het bestuurslid (Trouw, 20 november 1996).
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O. Brovarets’, Ol’ha, Kostiantyn S. Tsiupa, and Dmytro M. Hovorun. "Where Quantum Biochemistry Meets Structural Bioinformatics: Excited Conformationally-Tautomeric States of the Classical A·T DNA Base Pair." In DNA - Damages and Repair Mechanisms. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.94565.

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This Chapter summarizes recent quantum-chemical (QM) investigations of the novel conformational and tautomeric states on the potential energy hypersurface of the classical A·T/A·U nucleobase pairs. For the first time, it was observed 28 local minima for each base pair excluding enantiomers - planar, non-planar base pairs and structures with wobble geometry. Considered excited conformationally-tautomeric states of the classical A·T DNA base pair have been revealed in the Nucleic Acid Database by structural bioinformatics. These data shed light on the biological significance of the unusual A·T/A·U nucleobase pairs for the functioning of the nucleic acids at the quantum level.
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Moraes, Patrícia Milani de, Bruna de Lima Pereira, Ludmyla Toller Cocco, and Luciamare Perinetti Alves Martins. "AVALIAÇÃO DOS EFEITOS DA VITAMINA C SOBRE A DEFESA ANTIOXIDANTE ENZIMÁTICA NA FASE AGUDA DA DOENÇA DE CHAGAS EM CAMUNDONGOS EXPERIMENTALMENTE INFECTADOS COM A CEPA QM2 DE Trypanosoma cruzi." In As Ciências Biológicas e da Saúde na Contemporaneidade 2, 71–83. Atena Editora, 2019. http://dx.doi.org/10.22533/at.ed.1661928038.

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Conference papers on the topic "QMA DMA"

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Prohaska, Stevan, Aleksandra Ilić, and Pavla Pekarova. "ASSESSMENT OF STATISTICAL SIGNIFICANCE OF HISTORIC DANUBE FLOODS." In XXVII Conference of the Danubian Countries on Hydrological Forecasting and Hydrological Bases of Water Management. Nika-Tsentr, 2020. http://dx.doi.org/10.15407/uhmi.conference.01.05.

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Data on historic floods along the Danube River exist since the year 1012. In the Middle Ages, floods were estimated based on historical documents, including original handwritten notes, newspaper articles, chronicles, formal letters, books, maps and photographs. From 1500 until the beginning of organized water regime observations, floods were hydraulically reconstructed based on water marks on old buildings in cities along the Danube (Passau, Melk, Emmersdorf an der Donau, Spilz, Schonbuhen and Bratislava). The paper presents a procedure for assessing the statistical significance of registered historic floods using a comprehensive method for defining theoretical flood hydrographs at hydrological stations. The approach is based on correlation analysis of two basic flood hydrograph parameters – maximum hydrograph ordinate (peak) and flood wave volume. The PROIL model is used to define the probability of simultaneous occurrence of these parameters. It defines the exceedance probability of two random variables, in the specific case two hydrograph parameters of the form: P{Qmax more equal to qmax,p)∩(Wmax more equal to wmax,p)} = P (1) where: Qmax – maximum hydrograph ordinate (peak); qmax,p – maximum discharge of the probability of occurrence p; Wmax – maximum hydrograph volume; wmax,p – maximum flood wave volume of the probability of occurrence p; P – exceedance probability. Spatial positions of the lines of exceedance of two flood hydrograph parameters and the empirical points of the corresponding parameters of the considered historic flood in the correlation field Qmax - Wmax, allow direct assessment of the exceedance probability of a historic flood, or its statistical significance. The proposed procedure was applied in practice to assess the statistical significance of the biggest floods registered along the Danube in the sector from its mouth to the Djerdap 1 Dam. The linear trend in the time-series of maximum annual flows at a representative hydrological station and the frequency of historic floods in the considered sector of the Danube are discussed at the end of the paper.
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Silva, Leticia Canali da, Gustavo Fernandes Mafra, Amanda Marcondes Pires, Alice Ribeiro Faccio, Henrique Moretti Greco, and Isaac Romani. "Prevalência da mutação causadora da Paralisia Periódica Hipercalêmica em equinos da raça Quarto de milha na região centro norte do Paraná." In II Congresso Internacional Interdisciplinar da Uningá. Editora Uningá, 2023. http://dx.doi.org/10.46311/ed.un.20221018178.

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A Paralisia Periódica Hipercalêmica (HYPP) é uma doença causada pela mutação no gene SCN4A resultando em fraqueza muscular, contrações involuntárias e hipercalemia, podendo levar a óbito. O objetivo do estudo foi avaliar a prevalência da mutação causadora da HYPP na região centro norte do Paraná em equinos QM das modalidades de laço e três tambores. Após a coleta de pelo da cauda de 52 animais, as amostras foram encaminhadas para extração, quantificação, amplificação por primers específicos do gene SCN4A e sequenciamento em laboratório terceirizado. Os resultados revelaram que nenhum dos animais apresentou a mutação causadora do HYPP.
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FLAVIA DOS SANTOS, ANA, ABNER DE SIERVO, and EDSON PEDRO CECÍLIO JUNIOR. "Desenho e Construção de uma micro balança a quartzo (QMB) transferível em ultra alto vácuo." In XXIV Congresso de Iniciação Científica da UNICAMP - 2016. Campinas - SP, Brazil: Galoa, 2016. http://dx.doi.org/10.19146/pibic-2016-51164.

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Raschke, Scott A., Gregory S. Paxson, and Edward Raptosh. "George B. Stevenson Dam Rehabilitation—The Importance of Uncertainty and Confidence Evaluation in Quantitative Risk Assessments (QRA) Using Risk-Informed Decision Making (RIDM) Process." In Eighth International Conference on Case Histories in Geotechnical Engineering. Reston, VA: American Society of Civil Engineers, 2019. http://dx.doi.org/10.1061/9780784482155.014.

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Souza, Simone Raimondi de, Giulia Modesto Guimaraes de Mattos Moura, Rafaela Carvalho Rodrigues, Giulia Rodrigues Castro de Lima, and Lilian Cristina Caldeira Thomé. "Integralidade do atendimento à gestante de alto risco — um desafio para unidades de saúde públicas e privadas: relato de caso." In 47º Congresso da SGORJ e Trocando Ideias XXVI. Zeppelini Editorial e Comunicação, 2023. http://dx.doi.org/10.5327/jbg-2965-3711-2023133s1080.

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Introdução: A promoção da maternidade segura é uma meta de todo profissional de saúde. Gestações de alto risco requerem atenção especial às condições clínicas que podem agravar, interferindo no bom desenvolvimento materno-fetal. Nessas situações, a interlocução entre os diversos serviços dentro das unidades hospitalares se torna condição sine qua non para que, ao final, os desfechos sejam satisfatórios. Relato de caso: M.B.R.N., 33 anos, técnica de enfermagem, diabética tipo 1, infecção do trato urinário, 3 gestações, 1 parto vaginal e 1 cesárea, idade gestacional: 33 semanas e 6 dias, assintomática, é encaminhada à maternidade pela Clínica da Família por pressão arterial (PA) elevada, com 6 consultas de pré-natal. No exame físico na admissão: PA: 150 × 110 mmHg, eucárdica, eupneica, afebril, glicemia capilar: 113 mg/dL, edema de membros inferiores, amputação das falanges e parte dos metatarsos do pé esquerdo em 2022 pós-traumatismo e microangiopatia diabética, coto de pé diabético infectado, com exsudato, secreção serosa e odor fétido. No exame obstétrico: dilatação uterina: 0, altura uterina: 32 cm, tônus uterino: normal, colo fechado, grosso e posterior. Apresentação cefálica alta, bolsa íntegra, batimento cardíaco fetal: 141 bpm, cardiotocografia: CAT1. No laboratório: VDRL-, HIV-, tipo sanguíneo O+, hemoglobina: 10 mg/dL, hematócrito: 30,9%, plaquetas: 375.000, leucócitos: 11.600, INR: 0,85, EAS: glicosúria, Spot: 1,6 (vasculopata), proteinúria: 3+/4+. Em uso de insulina NPH+ regular, mantida. Iniciada dexametasona para amadurecimento pulmonar fetal. Solicitado parecer da Cirurgia Vascular quanto à amputação e da Ortopedia quanto à osteomielite, tendo sido liberada por ambos os Serviços para seguir com a gestação, desde que apresentasse condição clínica estável. Feita otimização do tratamento para controle pressórico da pré-eclâmpsia (PE), glicêmico e, após discussão com a Comissão de Controle de Infecção Hospitalar, da infecção no coto, com cefuroxima 750 mg, clindamicina 900 mg e ciprofloxacino 400 mg, todos IV 8/8h. Após 7 dias de internação, houve descompensação glicêmica, sendo decidida a interrupção da gestação por via alta. O recém-nascido é do sexo feminino, pesando 2.200 g, medindo 45 cm, com Apgar 7/8, e apresentou intercorrência: circular triplo de cordão em região cervical com nó verdadeiro, necessitando de cuidados em unidade de terapia intensiva, sendo nutrida com leite materno ordenhado. Ao longo da internação, a paciente também foi assistida pelo Serviço de Cirurgia Plástica, que procedeu ao desbridamento da ferida no coto. Recebeu alta após 22 dias de internação, com pressão arterial e glicemia controladas, além de remissão da infecção. Comentários: O presente relato evidencia a importância do olhar clínico presente no cuidado obstétrico e a necessidade do trabalho multidisciplinar, a fim de buscar o equilíbrio do sistema complexo e adaptativo que é o corpo humano, sobretudo quando em estado gravídico. Os desfechos favoráveis do presente relato se devem primordialmente à sintonia entre as equipes e à dedicação humanizada prestada ao binômio mãe-bebê.
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Nash, Grant S., Jason C. Ross, Basant K. Parida, Abdullatif K. Zaouk, and Swamidas K. (John) Punwani. "Variable Directivity Acoustical Warning Device (AWD) as an Optimized Locomotive Horn." In ASME 2012 Rail Transportation Division Fall Technical Conference. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/rtdf2012-9438.

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It is estimated that up to 9.3 million people may be impacted by locomotive horn noise and up to 4.6 million of those may be severely impacted.1 In 2009, there were over 1,900 incidents, over 700 injuries, and over 240 fatalities at highway-rail grade crossings.2 Approximately 4,000 times per year, a train and highway vehicle collide at one of over 262,000 public and private highway-rail grade crossings in the United States. Compared to a collision between two highway vehicles, a collision with a train is eleven times more likely to result in a fatality, and five and a half times more likely to result in a disabling injury. Approximately half of all collisions occur at grade crossings that are not fully equipped with warning devices. Some of the drivers involved in these collisions may have been unaware of the approaching train.3 The National Academy of Engineering Committee on Technology for a Quieter America has indicated that the public would benefit if a train horn was more directional and has recommended that research and development be undertaken to better understand the effects on safety, with benefits to the public.4 As a part of an ongoing Federal Railroad Administration (FRA)-sponsored research and development effort, the authors have developed an Acoustical Warning Device (AWD) prototype with an overall goal of maximizing safety at a grade crossing and minimizing environmental noise pollution (at the wayside and in the cabin of a locomotive in reducing railroad worker occupational hazard noise exposure). An initial prototype was created that consisted of one acoustical element. An advanced prototype is currently being developed with three acoustical elements to provide variable directivity and steering capabilities through beamforming. A digitized horn signal has been created based on characteristics from an analog air-pressure locomotive horn. The initial AWD prototype has been analyzed for detectability and noise impact area and the directivity pattern of its sound emissions have been tested. The expected performance of the advanced three-unit prototype has been evaluated based on the test results of the initial prototype and acoustic simulation modeling. During development of the initial AW D prototype, spectrograms, polar directivity plots, frequency response plots, 1/3-octave band plots, and LAeq measurements of the AWD propagation were analyzed to ensure proper functionality of the AWD, in accordance with FRA and QinetiQ North America’s (QNA) specifications. Based on acoustic simulation modeling, the advanced AWD prototype is expected to generate sound up to 110 dBA at 100 feet forward of the locomotive. The AWD prototype is expected to improve detectability and reduced environmental noise exposure to the community and locomotive cabin.
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Reports on the topic "QMA DMA"

1

Weidert, J. R. DMS release 2 quality assurance (QA) plan. Office of Scientific and Technical Information (OSTI), January 1997. http://dx.doi.org/10.2172/328701.

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