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Articles de revues sur le sujet "U-LTS model"
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Ohkubo, M., G. Uehara, J. Beyer, M. Mimura, H. Tanaka, K. Ehara, S. Tanaka et al. « Standard measurement method for normal state resistance and critical current of resistively shunted Josephson junctions ». Superconductor Science and Technology 35, no 4 (14 février 2022) : 045002. http://dx.doi.org/10.1088/1361-6668/ac4f3b.
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Abstract An important parameter of Josephson junctions (JJs) is the product of normal state resistance (R n) and critical current (I c) for designing superconductor analogue devices or digital circuits. Determination of R n and I c from voltage–current (U–I) characteristic curves often faces difficulties; in particular I c is considerably reduced by intrinsic thermal or extrinsic electrical noises. Here, we propose a standard measurement method of R n and intrinsic critical current (I ci) for high-T c superconductor (HTS) grain boundary JJs operated in liquid nitrogen and low-T c superconductor (LTS) multilayer superconductor/normal-conductor/superconductor (SNS) JJs in liquid helium. The applicable condition of this method is that both HTS and LTS JJs have U–I curves compatible with resistively-shunted junction (RSJ) model. Both R n and I ci values are extracted by combining a geometric mean criterion to select a data set and a least-squares fitting method with the RSJ model, eliminating two distortion effects on U–I curves: noise-rounding and self-heating. The combined method ensures relative standard uncertainty values of 1.9% for R n and 8% for I ci or better, when the users follow the standard protocol. It is demonstrated that the combined method is valid for d-wave HTS JJs near 77 K, regardless of peculiarities such as 0–π junction transition in d-wave superconductors at lower temperatures, and s-wave LTS SNS JJs with a wide range of junction parameters. This work is the first step to facilitate standardization for superconductor electronics with JJs.
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Doucet, M. Y., T. R. Jones et A. W. Ford-Hutchinson. « Responses of equine trachealis and lung parenchyma to methacholine, histamine, serotonin, prostanoids, and leukotrienes in vitro ». Canadian Journal of Physiology and Pharmacology 68, no 3 (1 mars 1990) : 379–83. http://dx.doi.org/10.1139/y90-053.
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The responses of equine trachealis and lung parenchymal strips to a range of contractile agonists were studied. Equine trachealis responded to methacholine > histamine > serotonin as shown by the maximal responses but failed to respond to either leukotrienes (LT), prostaglandin F2α, or U-44069. Equine parenchymal strips showed considerable tonal activity and responded to LTD4[Formula: see text]LTC4 > U-44069 = LTE4 > methacholine [Formula: see text] histamine [Formula: see text] serotonin > prostaglandin F2α as determined through pD2 values. Neither the concentration response curve to LTD4 nor the intrinsic tonal activity of the preparations was modified by pretreatment with either atropine or indomethacin, although the maximal response to LTD4 was reversed by addition of the LTD4 receptor antagonist, MK-571. Thus arachidonic acid metabolites, including LTs, must be considered potential mediators of equine small airway disease, a potential model of human bronchial asthma.Key words: horse, leukotrienes, U-44069, trachea, lung parenchyma.
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He, Shuai, Yinghua Zhang, Zhian Huang, Ge Zhang et Yukun Gao. « Influence of Internal Structure and Composition on Head’s Local Thermal Sensation and Temperature Distribution ». Atmosphere 11, no 2 (21 février 2020) : 218. http://dx.doi.org/10.3390/atmos11020218.
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A personalized thermal environment is an effective way to ensure a good thermal sensation for individuals. Since local thermal sensation and temperature distribution are affected by individual physiological differences, it is necessary to study the effects of physiological parameters. The purpose of this study was to investigate the effects of internal structures and tissue composition on head temperature distribution and thermal sensation. A new mathematical model based on fuzzy logic control was established, the internal structure and tissue composition of the head were obtained by magnetic resonance imaging (MRI), and the local thermal sensation (LTS) index was used to evaluate the thermal sensation. Based on the mathematical model and the real physiological data, the head temperature and local sensation changes under different parameters were investigated, and the sensitivity of thermal sensation relative to the differences in tissue thickness was analyzed. The results show that skin tissue had the highest influence ( C s k i n = 0.0180 ) on head temperature, followed by muscle tissue ( C m u s c l e = 0.0127 ), and the influence of adipose tissue ( C f a t = 0.0097 ) was the lowest. LTS was most sensitive to skin thickness variation, with an average sensitivity coefficient of 1.58, while the muscle tissue had an average sensitivity coefficient of 0.2, and the sensitivity coefficient of fat was relatively small, at a value of 0.04.
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Telzerow, Eva, Dennis Görlich, Maja Rothenberg-Thurley, Maria Cristina Sauerland, Anna Sophia Moret, Friederike H. A. Mumm, Susanne Amler et al. « Quality of Life and Life Satisfaction in AML Long-Term Survivors : Primary Results of the AMLCG-Survivorship Study ». Blood 138, Supplement 1 (5 novembre 2021) : 2289. http://dx.doi.org/10.1182/blood-2021-147027.
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Abstract Introduction An increasing proportion of patients with Acute Myeloid Leukemia (AML) become long-term survivors. Somatic and psycho-social outcomes are therefore becoming increasingly important, but little is known about the long-term effects of the disease and its treatment. Methods We designed a comprehensive analysis of AML survivorship outcomes including psycho-social well-being and somatic health status and conducted a questionnaire-based study collecting data from AML long term survivors (AML-LTS) and their physicians. This report focuses on overall and health-related quality of life. Somatic, especially cardiovascular, morbidity in AML-LTS are reported separately (Moret et al.). The primary aim of this study was to compare quality of life (QoL, measured by the FACT-G questionnaire) and general and health-related life satisfaction (gLS/hLS, measured by the FLZ-M questionnaire) of AML-LTS with normative data of German adults who were not diagnosed with AML (Holzner et al. 2009; Daig et al. 2009). FLZ-M and FACT-G scores were standardized relative to the normal population mean and standard deviation, stratified by sex and age. These z-scores were then tested against the fixed value 0 (indicating no difference between AML-LTS and the general population) using Mann-Whitney U-tests. Our statistical design incorporated a sequentially rejective testing procedure to maintain the multiple testing significance level at 5%, using a graphical model as described by Bretz et al. (2009). Results 427 former AML patients who had been enrolled in AMLCG trials (AMLCG-1999, AMLCG-2004, AMLCG-2008) or the AMLCG patient registry, participated in this study between 5 and 18.6 years [y] after their initial AML diagnosis (median, 11.3y). Median age of AML-LTS was 61y (range 28y-93y), and 56% were female. Thirty-eight percent of participants had been treated with chemotherapy alone, while 62% received at least one allogeneic stem cell transplant (alloSCT). A relapse occurred in 24% of the participants. Unexpectedly, quality of life and general life satisfaction summary scores were significantly higher in AML-LTS (p<.001) compared to adults without the diagnosis of AML, although most differences on QoL subscales relative to the general population were small and very likely not clinically relevant. No statistical difference between AML-LTS and normal adults was found for health-related life satisfaction (hLS). Notably, a subgroup of participants (26%) reported poor physical well-being (PWB), indicated by a FACT PWB subscore more than one standard deviation (SD) below the age- and sex-matched general population value (Figure A). This resulted in poor overall QoL (i.e. >1 SD below normal) for 13% of the participants (Figure B). To identify factors potentially associated with poor overall QoL, we constructed a logistic regression model including pre-specified cofactors (age, sex, time since initial diagnosis, relapse and alloSCT) and additional covariables that associated with QoL in univariate analyses (Table C). We found that participants with younger age, male sex, lower educational level, shorter time since diagnosis and a altered financial situation reported significantly lower QoL. No influence was found for other characteristics including treatment (alloSCT vs. no alloSCT), previous relapse, or de novo vs. secondary or therapy-related AML. Discussion Unlike previous studies of AML survivorship, our large cohort included a diverse spectrum of patients regarding age, time since diagnosis, and treatment modalities, which allows for new insight into long-term quality of life. Our study establishes that overall QoL in AML long-term survivors is comparable to the general population. Improvement of QoL continues beyond five years post diagnosis. Importantly, disease- and treatment-related factors, such as prior relapse or status post allogeneic transplantation, are not associated with overall QoL. However, we were able to identify risk factors for worse QoL (younger age, male sex, alteration of the financial situation), delineating a subgroup of patients that may still have a need for targeted psycho-social interventions five or more years after an AML diagnosis. Figure 1 Figure 1. Disclosures Berdel: Philogen S.p.A.: Consultancy, Current equity holder in publicly-traded company, Honoraria, Membership on an entity's Board of Directors or advisory committees. Hiddemann: Janssen: Research Funding; Roche: Membership on an entity's Board of Directors or advisory committees, Research Funding. Metzeler: AbbVie: Honoraria; Astellas: Honoraria; Daiichi Sankyo: Honoraria; Novartis: Consultancy; Jazz Pharmaceuticals: Consultancy; Pfizer: Consultancy; Celgene/BMS: Consultancy, Honoraria, Research Funding.
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Bakhsham, Milad, Mahdi Hosseinpour, Masoumeh Ayeneh, Hossein Karimi et Parisa Parandavar. « Identifying and Analyzing the Application of the Internet of Things in Supply Pharmaceutical Chain Agility in post COVID -19 ». Journal of Health and Biomedical Informatics 10, no 1 (22 mai 2023) : 57–69. http://dx.doi.org/10.34172/jhbmi.2023.14.
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Introduction: The internet of Things has become more popular as a new technology since the advent of wire less technology , and attracted attention from supply chain management promoters. This study aimed to identify and analyze IoT applications in the pharmaceutical supply chain agility in the post -COVID -19 era Method: We first review previous studies in appl ications of IoT in pharmaceutical supply chain agility and identified the findings through qualitative content analysis. Then, the identified factors were given to 20 management and information technology experts to confirm and validat e. Results: The resu lts showed that IoT applications on the pharmaceutical supply chain agility in 9 components and 50 indicators. First of all, the most important factor is faster communication with other stakeholders (suppliers, manufacturers, distributors, and customers) u sing the IoT in the supply chain . Secondly, the use of IoT for drug production; manufacturers invest in technologies that lead to lower operating costs in the long term, because network devices and sensors do not make mistakes, do not need rest and trainin g, and do not take vacations. Therefore, they increase the agility of the production process and are a reliable and cost -effective alternative for productivity in production. Conclusion: The wide applications of the proposed model indicate the need to cons ider the use of the IoT in the pharmaceutical industry supply chain in order to improve overall supply chain performance and focus on supply chain agility.
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Reddy, S. Reddy Vamshidhar, et Sanjay Dhar Roy. « SBT (Sense Before Transmit) Based LTE Licenced Assisted Access for 5 GHz Unlicensed Spectrum ». Wireless Personal Communications 119, no 3 (3 mars 2021) : 2069–81. http://dx.doi.org/10.1007/s11277-021-08318-1.
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AbstractUtilization of unlicensed spectrum under licensed assisted access ensuring fair co-existence with Wi-Fi networks is a good solution to address immense usage of mobile data. Radio communication operation of LTE in unlicensed frequency band is referred as LTE-unlicensed (LTE-U) or LTE-licensed assisted access. In this paper, we consider a HGNW in which coverage area of Wireless-Fidelity (Wi-Fi)’s Access Point is integrated within the LTE-U small base station’s cellular network coverage area. To overcome the disadvantages of existing LTE-U technics like carrier sense adaptive transmission and listen before talk, we proposed a new methodology i.e., sense before transmit in this paper by adopting a transmit power control mechanisms using reciprocity theorem based on the channel state information to assign the secondary carriers in the uplink as well as in the downlink directions in the unlicensed spectrum to carry the traffic. In our proposal, LTE-U users are allowed to use the unlicensed spectrum provided that the interference produced at Wi-Fi users due to LTE-U activities is remained below a certain threshold. We evaluated the performance of proposed network model in terms of outage probability and achievable throughputs.
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Girmay, Merkebu, Vasilis Maglogiannis, Dries Naudts, Adnan Shahid et Ingrid Moerman. « Coexistence Scheme for Uncoordinated LTE and WiFi Networks Using Experience Replay Based Q-Learning ». Sensors 21, no 21 (21 octobre 2021) : 6977. http://dx.doi.org/10.3390/s21216977.
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Nowadays, broadband applications that use the licensed spectrum of the cellular network are growing fast. For this reason, Long-Term Evolution-Unlicensed (LTE-U) technology is expected to offload its traffic to the unlicensed spectrum. However, LTE-U transmissions have to coexist with the existing WiFi networks. Most existing coexistence schemes consider coordinated LTE-U and WiFi networks where there is a central coordinator that communicates traffic demand of the co-located networks. However, such a method of WiFi traffic estimation raises the complexity, traffic overhead, and reaction time of the coexistence schemes. In this article, we propose Experience Replay (ER) and Reward selective Experience Replay (RER) based Q-learning techniques as a solution for the coexistence of uncoordinated LTE-U and WiFi networks. In the proposed schemes, the LTE-U deploys a WiFi saturation sensing model to estimate the traffic demand of co-located WiFi networks. We also made a performance comparison between the proposed schemes and other rule-based and Q-learning based coexistence schemes implemented in non-coordinated LTE-U and WiFi networks. The simulation results show that the RER Q-learning scheme converges faster than the ER Q-learning scheme. The RER Q-learning scheme also gives 19.1% and 5.2% enhancement in aggregated throughput and 16.4% and 10.9% enhancement in fairness performance as compared to the rule-based and Q-learning coexistence schemes, respectively.
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Zhiqun, Hu, Lu Zhaoming, Lin Shangjuan, Wen Xiangming et Xu Hen. « Performance analysis of LTE-U coexistence network with WiFi using queueing model ». Journal of China Universities of Posts and Telecommunications 24, no 5 (octobre 2017) : 1–7. http://dx.doi.org/10.1016/s1005-8885(17)60227-9.
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Baswade, Anand M., Mohith Reddy, Antony Franklin A., Bheemarjuna Reddy Tamma et Vanlin Sathya. « Performance analysis of spatially distributed LTE-U/NR-U and Wi-Fi networks : An analytical model for coexistence study ». Journal of Network and Computer Applications 191 (octobre 2021) : 103157. http://dx.doi.org/10.1016/j.jnca.2021.103157.
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Przesmycki, Rafał, et Marek Bugaj. « Crescent Microstrip Antenna for LTE-U and 5G Systems ». Electronics 11, no 8 (9 avril 2022) : 1201. http://dx.doi.org/10.3390/electronics11081201.
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The field of wireless cellular network technology has seen a significant development in recent years, allowing the emergence of many new applications in addition to the traditional mobile phone calls. We are currently implementing the 5G system, which is replacing the previous cellular technologies on the market. Parallel to the development of cellular technologies, wireless local networks based on the IEEE 802.11× standards are rapidly spreading. The desire to use the advantages of both mobile telephony and wireless local networks has led to the idea of integrating the currently used communication systems in one device and requires a well-designed antenna, which should be given a lot of attention when designing the radio system. This article presents the proposed model of a two-band microstrip antenna for which the main assumption is its operating frequencies in the LTE-U (LTE-Unlicensed) band and one of the 5G system bands. The antenna dimensions and parameters have been calculated, simulated, and optimized using CST Microwave Studio software. The developed antenna has a compact structure with dimensions of (60 × 40 × 1.57) mm. The dielectric material RT Duroid 5880 with a dielectric constant εr = 2.2 and thickness h = 1.57 mm was used as a substrate for the antenna construction. The article presents an analysis of the results of simulation and measurements of selected electrical parameters and radiation characteristics of the proposed antenna. The antenna described in the article, working in 5G systems and LTE-U systems, is characterized by two operating bands with center frequencies equal to 3.52 GHz and 5.37 GHz, a low reflection coefficient (for resonances −31.54 dB and −23.16 dB), a gain value of 4.45 dBi, a wide frequency band of 3.0 GHz (68.18%), and a high energy efficiency in the range of 80–96.68%.
Thèses sur le sujet "U-LTS model"
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Jimenez, Reyes Jose. « Experimental and numerical contribution to the study of transformation induced plasticity (TRIP) ». Electronic Thesis or Diss., Normandie, 2024. http://www.theses.fr/2024NORMIR20.
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Ce travail a été réalisé dans le but d'apporter une contribution à l'étude de la plasticité induite par transformation (TRIP) à travers des analyses expérimentales et numériques. Pour ce faire, du point de vue expérimental, un programme expérimental original sur l'acier 35NCD16 observant les comportements des transformations austénite → martensite est réalisé sous différentes conditions de chargement. Les résultats indiquent que : (i) le TRIP n'a pas d'effet mémoire significatif, (ii) le matériau peut présenter une récupération de l'écrouissage pendant la transformation martensite → austénite, (iii) une dissymétrie entre les réponses du TRIP en tension et en compression a été observée, (iv) l'existence d'une contre-contrainte du TRIP a été révélée, (v) la quantité de TRIP final peut être considérée comme proportionnelle à la norme de la contrainte appliquée tant que cette dernière ne dépasse pas la limite d'élasticité, et (vi) une légère orientation physique a toutefois été observée lors de l'analyse microstructurale de notre matériau, ce qui pourrait suggérer une faible contribution du mécanisme de Magee dans le TRIP. Quant au côté numérique, les capacités prédictives du modèle Leblond – Taleb – Sidoroff (LTS) et de sa version actualisée (U – LTS) sont mises à l'épreuve en simulant les essais expérimentaux réalisés dans le cadre de cette étude. Nos résultats montrent que (i) le modèle LTS surestime les résultats expérimentaux, (ii) le modèle LTS ne parvient pas à décrire la dissymétrie entre les réponses TRIP en tension et en compression, (iii) en utilisant le modèle U – LTS, les résultats comparatifs montrent d'excellentes capacités à simuler la base de données expérimentale réalisée dans ce travail, en particulier par rapport au modèle LTS. Bien que nos résultats expérimentaux aient montré des résultats significatifs, en particulier lorsqu'ils sont comparés aux modèles observés dans notre étude, il est recommandé de poursuivre les recherches en prenant en compte d'autres aciers et d'autres transformationsThis thesis has been created with the objective of providing a contribution to the study of transformation induced plasticity (TRIP) via experimental and numerical analyses. To do so, from the experimental point of view, an original experimental program on 35NCD16 steel observing the behaviors of austenite → martensite transformations were performed under different loading conditions. The results indicate that: (i) TRIP does not hold any significant memory effect, (ii) the material may present recovery from strain hardening during the martensite → austenite transformation, (iii) a dissymmetry between the TRIP responses under tension and compression were observed, (iv) the existence of TRIP backstress was revealed, (v) the amount of final TRIP may be considered proportional to the norm of the applied stress as long as the latter does not exceed the yield stress, and (vi) a slight physical orientation has however been observed when carrying out microstructural analyses on our material, which could suggest a small contribution of the Magee mechanism in TRIP. As for the numerical side, the predictive capabilities of the Leblond – Taleb – Sidoroff (LTS) model, and its updated version (U – LTS) are put to the test by simulating the experimental tests performed for this study. Our results show that: (i) the LTS model overestimates the experimental results, (ii) the LTS model fails in describing the dissymmetry between the TRIP responses under tension and compression, (iii) when using the U – LTS model, the comparative results show excellent capabilities in simulating the experimental data base performed in this work, especially compared to the LTS model. While our experimental results showed significant results, especially when put up against to the models observed in our study, further research considering other steels and other transformations is recommended
Livres sur le sujet "U-LTS model"
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Cheng, Russell. Indeterminacy. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780198505044.003.0014.
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This chapter discusses models like the exponential regression model y = a[1− exp(− bx)] where if a = 0 then b is an indeterminate, non-identifiable parameter, as it vanishes from the model. The hypothesis test that H0 : a = 0 versus H1 : a ≠ 0 is then non-standard. The well-known Davies test is explained. This uses a portmanteau test statistic T that is a functional of Sn(b), L< b< U, where Sn(b) is a regular test statistic of the null hypothesis a = 0 versus the alternative a ≠ 0 with b fixed. The null distribution of T is not usually easy to obtain. One can instead just test if a = 0 using a GoF test or a lack-of-fit test with an alternative hypothesis not specified. In the exponential regression example, this means simply testing if the observations are solely pure error. This elementary approach is compared with the Davies approach.
Chapitres de livres sur le sujet "U-LTS model"
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Takabe, Hideaki. « Basic Properties of Plasma in Fluid Model ». Dans Springer Series in Plasma Science and Technology, 15–97. Cham : Springer International Publishing, 2024. http://dx.doi.org/10.1007/978-3-031-45473-8_2.
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AbstractIf the spatial variation of plasma is longer than the particle mean free path and the time variation is sufficiently longer than the plasma Coulomb collision time, the plasma can be approximated as being in local thermal equilibrium (LTE) at any point (t, r). Then the velocity distribution functions of the particles become Maxwellian. In addition, assuming Maxwellian is also a good assumption in many cases even for collisionless plasmas such as high-temperature fusion plasmas. In the fluid model of plasmas, The plasmas can be described in terms of five variables characterizing local Maxwellian: the density n(t, r), flow velocity vector u(t,r), and temperature T(t, r). So, the mathematics used in fluid physics is widely applicable to studying plasma phenomena.Although conventional fluids are neutral, plasma fluids of electrons and ions couple with electromagnetic fields. It is, therefore, necessary to solve Maxwell’s equations simultaneously. It is also possible to approximate electrons and ions as two different fluids or as a single fluid in case-by-case. This requires an insight into what kind of physics is important in our problem.After reviewing the basic equation of fluids, several fluid models for plasmas are shown. Especially, a variety of waves appears because of charged particle fluids are derived to know why waves are fundamental to knowing the plasma dynamics. The mathematical method to obtain the wave solutions as an initial value problem is explained as well as the meaning of the resultant dispersion relations.Magneto-hydrodynamic equations (MHD) are derived to explain the effects of the Biermann battery, magnetic dynamo, etc. The relationship of magnetic field and vortex flow is studied. Resistive MHD is derived including the Nernst effect, which becomes important for the magnetic field in strong electron heat flux.Finally, electromagnetic (EM) waves in magnetized plasmas are derived to see how to use for diagnostics in the laboratory and observation of wide range of electromagnetic waves from the Universe.
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Werschulz, Arthur G. « Example : a two-point boundary value problem ». Dans The Computational Complexity of Differential and Integral Equations, 6–22. Oxford University PressOxford, 1991. http://dx.doi.org/10.1093/oso/9780198535898.003.0002.
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Abstract We use a simple example of a two-point boundary value problem (Lu)(x) = -u"(x) + u(x) = f(x) u'(O) = u'(l) = 0. for O < X < 1, to illustrate major issues and concepts of information-based complexity. First, we must describe our problem more carefully. That is, we specify the problem formulation, permissible information, and a model of computation.
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« Cash Management ». Dans Decision and Prediction Analysis Powered With Operations Research, 209–21. IGI Global, 2024. http://dx.doi.org/10.4018/979-8-3693-4179-7.ch011.
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The Miller-Orr cash management model is presented. Every day, if the cash on hand exceeds an upper limit U, enough cash is transferred into a money market to decrease the cash level to a target T. If the cash on hand is below a minimum level M, enough cash is transferred out of the money market to bring the cash level up to the target T. The cash flow is normally distributed with a zero mean and a standard deviation of $10,000. The decision variables are U and T. Minimum level M is set to $15,000. The objective is to maximize the mean profit over the time horizon, where profit is interest on the money market minus the transaction's costs. The constraints are that M <= T <= U. T and U should be round numbers with discrete options on adjustable cells, using a step size of $100.
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V.M.S.N, Ch Pavan Kumar, H. D. Praveena, GRK Prasad et S. Harichandra Prasad. « LOW-PROFILE DUAL-BAND FILTERING PATCH ANTENNA FOR LTE AND ISM BAND APPLICATIONS ». Dans Futuristic Trends in Network & ; Communication Technologies Volume 3 Book 2, 19–26. Iterative International Publisher, Selfypage Developers Pvt Ltd, 2024. http://dx.doi.org/10.58532/v3bgnc2p1ch3.
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This paper introduces a compact dual-band filtering patch antenna element and demonstrates its suitability for two specific frequency bands: LTE (Long Term Evolution) in the L-band and ISM (Industrial, Scientific, and Medical) band in the S-band. The proposed design comprises two distinct U-shaped patches, with a smaller patch nested within a larger one. To achieve dual-band resonance, a multi-stub microstrip feed line is employed, allowing independent control of the resonant modes of both patches and the feed line. This flexibility enables precise tuning of the antenna's operating frequencies. In this study, we implement a low-profile dual-band antenna element operating at 1.9GHz (LTE band) and 2.4GHz (WLAN), which is subsequently simulated and validated using the FEKO Tool. It's worth noting that this design can be adapted for different frequency ranges and applied to various wireless communication applications.
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Silva, Cícero José da, Willames de Albuquerque Soares, Sérgio Mário Lins Galdino, Jornandes Dias da Silva et Juan Carlos Oliveira de Medeiros. « A look at the composition of linear transformations in the language of matrices, some types of matrices of order 2 represented geometrically in the R2 plane ». Dans Eyes on Health Sciences V.02. Seven Editora, 2024. http://dx.doi.org/10.56238/sevened2024.001-064.
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The purpose of this note is to present compositions of linear transformations in the language of matrices, as well as to present geometric interpretations for some particular cases of order 2 matrices such as reflections around the x and y axes, reflections around the origin, contraction, expansion or homothetic, horizontal and vertical shear, counterclockwise rotation, orthogonal projection of u = (x, y) on the line G : y = ax, a /= 0, as well as the reflection of the same vector around this same line. It is worth mentioning that your compositions in the language of matrices is a first model of computer graphics. Illustratively, for example, the expansion of factor k : Hk (x, y) = (kx, ky) or in the language of matrices, represents a computer zoom by zooming if k > 1 or contracting if 0 < k < 1.
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Boniface, Nelson, et Tatsuki Tsujimori. « New tectonic model and division of the Ubendian-Usagaran Belt, Tanzania : A review and in-situ dating of eclogites ». Dans Plate Tectonics, Ophiolites, and Societal Significance of Geology : A Celebration of the Career of Eldridge Moores. Geological Society of America, 2021. http://dx.doi.org/10.1130/2021.2552(08).
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ABSTRACT Records of high-pressure/low-temperature (HP-LT) metamorphic interfaces are not common in Precambrian orogens. It should be noted that the association of HP-LT metamorphic interfaces and strongly deformed ocean plate stratigraphy that form accretionary prisms between trenches and magmatic arcs are recognized as hallmark signatures of modern plate tectonics. In East Africa (Tanzania), the Paleoproterozoic Ubendian-Usagaran Belt records a HP-LT metamorphic interface that we consider as a centerpiece in reviewing the description of tectonic units of the Ubendian-Usagaran Belt and defining a new tectonic model. Our new U-Pb zircon age and the interpretations from existing data reveal an age between 1920 and 1890 Ma from the kyanite bearing eclogites. This establishment adds to the information of already known HP-LT metamorphic events at 2000 Ma, 1890–1860 Ma, and 590–520 Ma from the Ubendian-Usagaran Belt. Arc–back-arc signatures from eclogites imply that their mafic protoliths were probably eroded from arc basalt above a subduction zone and were channeled into a subduction zone as mélanges and got metamorphosed. The Ubendian-Usagaran events also record rifting, arc and back-arc magmatism, collisional, and hydrothermal events that preceded or followed HP-LT tectonic events. Our new tectonic subdivision of the Ubendian Belt is described as: (1) the western Ubendian Corridor, mainly composed of two Proterozoic suture zones (subduction at 2000, 1920–1890, Ma and 590–500 Ma) in the Ufipa and Nyika Terranes; (2) the central Ubendian Corridor, predominated by metamorphosed mafic-ultramafic rocks in the Ubende, Mbozi, and Upangwa Terranes that include the 1890–1860 Ma eclogites with mid-ocean ridge basalt affinity in the Ubende Terrane; and (3) the eastern Ubendian Corridor (the Katuma and Lupa Terranes), characterized by reworked Archean crust.
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Baird, Graham B., Fawna J. Korhonen et Kevin R. Chamberlain. « Pressure-temperature-deformation-time path for the Seve Nappe Complex, Kebnekaise Massif, Arctic Swedish Caledonides ». Dans New Developments in the Appalachian-Caledonian- Variscan Orogen. Geological Society of America, 2022. http://dx.doi.org/10.1130/2021.2554(12).
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ABSTRACT The Seve Nappe Complex in the Scandinavian Caledonides records a range of peak metamorphic conditions and timings. To better understand pressure-temperature-deformation-time differences throughout the complex and possible tectonic scenarios, metamorphosed mafic rocks within the Tarfala Valley of the Kebnekaise Massif (Sweden) were investigated using integrated petrologic and geochronologic techniques. Thermodynamic modeling of two samples using domainal and whole-rock compositions integrated with mineral chemistry, mineral textures, and titanite and zircon U-Pb geochronology constrained a portion of the pressure-temperature (P-T) path. Peak metamorphic conditions of 590–660 °C and 9.7–10.5 kbar were followed by near-isothermal decompression or a subsolidus clockwise P-T path. Amphibolite units in the valley record retrograde conditions at 450–550 °C at less than 7.5 kbar, although mineral modes and textures are most consistent with pressures <4 kbar. The majority of titanite growth occurred due to the introduction of hydrous fluids during cooling and following exhumation to midcrustal levels. U-Pb ages of retrograde titanite define a spread from ca. 480 to 449 Ma, and the oldest age is interpreted to constrain the timing of retrogression following exhumation. This interpretation is supported by a U-Pb zircon crystallization age of 481 ± 7 Ma for a metamorphosed intermediate to felsic synkinematic dike hosted in one of the amphibolite units. These results indicate that the Kebnekaise region records Early Ordovician deformation and metamorphism that was of lower grade compared to other Seve Nappe Complex locations to the south. The tectonic history of these rocks includes metamorphism and exhumation during the Cambrian–Ordovician pre-Scandian event, followed by thrusting of the Seve Nappe Complex and neighboring rocks onto Baltica during the Silurian Scandian orogeny.
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Köse, Oğuzhan, et Ramazan Ceylan. « Genç Futbolcuların, Aerobik ve Anaerobik Kapasiteleri Futbola Özgü Teknik Becerilerini Nasıl Etkiler ? » Dans Antrenman Biliminde Sürdürülebilirlik ve Nitel Araştırmalar. Özgür Yayınları, 2024. http://dx.doi.org/10.58830/ozgur.pub487.c2025.
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Bu araştırmanın amacı genç futbolcuların aerobik ve anaerobik kapasiteleri ve futbola özgü teknik becerilerinin incelenmesidir. Bu araştırmada nicel araştırma yöntemlerinden tarama modeli kullanıldı. Araştırmanın örneklem grubu Bayburt Özel İdare Spor Kulübü U-19 kategorisinde futbol oynayan 38 futbolcudan oluşturuldu. Futbolculardan antropometrik ölçümler (boy, kilo), anaerobik testler (dikey sıçrama testi, esneklik testi, illinois çeviklik testi, bacak kuvvet testi, yıldız denge testi), aerobik test (cooper testi) ve Mor-christian genel futbol yetenek testi (top sürme, şut ve pas isabeti) ölçümleri alındı. Araştırma sonucunda elde edilen ölçüm sonuçları SPSS 22 paket programına aktarılarak öncelikle normallik testi uygulandı. Yapılan ölçümlerde elde edilen verilerin ortalama ve standart sapma değerleri hesaplandı. Elde edilen sonuçlara göre veri dağılımının çarpıklık ve basıklık değerleri, Tabachnick ve Fidell (2013)’in bir verinin normal dağılıp dağılmadığının göstergesi olarak bildirdiği -1,5 ile + 1,5 arasında olduğu görüldü ve verilerin normal dağılım gösterdiği anlaşıldı. Normal dağılım gösteren bu veri setlerinin analizlerinde parametrik testlerden One Away Anova (Tek Yönlü Varyans Analizi) ve descriptives testleri yapıldı. Sporculara uygulanan testler sonucunda futbolcuların anaerobik testleri (çeviklik, esneklik, bacak kuvvet, dikey sıçrama ve yıldız denge) aerobik testi(dayanıklılık) futbola özgü becerilerin ve yeteneklerin (top sürme, şut ve pas isabeti) uygulanması üzerinde sırasıyla (p<,000-, p<,000-, p<,000) anlamlı farklılık olduğu bulgularına ulaşıldı. Çalışmanın sonucu olarak motor becerlerilerin (çeviklik, esneklik, kuvvet, dayanıklılık ve güç) futbola özgü teknik becerileri (top sürme, şut ve pas isabeti) olumlu yönde etkilediği düşünülmektedir.
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L.Sihler, Andrew. « Neuter r/n-Stems ». Dans New Comparative Grammar of Greek and Latin, 298–301. Oxford University PressNew York, NY, 1995. http://dx.doi.org/10.1093/oso/9780195083453.003.0062.
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Abstract In a number of IE languages we find neuter nouns which end in -r (in Inir. also -r;t, -r;k) in the nom./acc.sg., in some derivatives, and sometimes in the nom./acc.pl., but which build the other cases (and some derivatives) to a stem in -n-. Hence the term ‘r/ n-stems’. This mode of inflection is attested only very fragmentarily within the familiar IE languages, but the type is obviously both ancient and important. For one thing, the lexicon involved belongs to the most basic stramm of vocabulary -body parts and words like ‘water’, ‘fire’, ‘blood’, and ‘day’. For another, though any given language has only a handful of such items, there is little lexical agreement from language to language, so that even though the type is attested only in scraps, the sum of words pointing to r/ n-inflection is considerable. The original, unaltered, mode of inflection is scantily attested within the familiar IE languages: L femur, feminis ‘thigh’ (remodeled femoris also oc curs); U utur acc. ‘water’, une abl. < ‘udni or ‘udneH1; or Ved. fidhar nom./ acc. ‘udder’, fidhnas gen. Less obvious, though in fact relatively untampered-with, is the G type vowp, voarnc;- ‘water’ and 1rap, ij1raroc;- ‘liver’, in which the stem -ar- somehow continues “-1J- (288).
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« requirement of memory is large. So in this paper we propose an ae q p pu i r oe e a ce h bo a sf e de emo ty h es slli nr r d ie e r to o r en n c ni i s - struction of autocorrela (2) Nyquist sam pr u o le so isoe [ ] e [ ] a i , tp p i or oon cs t non w sn u struction p rop f os aaew he oani hh orrfebg ea s t si modnog oy n o ds tnhlceap eg oir fd . o rr - mance in th st t mm e wes i t t] a h ee p ] l , raota io ch nbfausnecdti on th wei th in d s ir uebc -t recon- plexity. In t mc ueie hn s o dr tauhm , Ct pilloA Fs t [ o i o8 a b lt e aw c s tr iicrcs pl a cg gie mu oon - eh d be y ha e constructed al u cty e o rI nNe at hqt oi s n fe u nh m c td p m io nC s , a[ i7Fn dm iisst ew bbn sh iii ge etn ae l detection is gtr e et d ac r ie n oo f en t pio e fa n s hen sig p n re nals, multi-c ae o r re i et t r sc n ig nl sdea la r i ’ sy gto . g n uI onrm be h e rt mio fe nats uf coub , ctC io AnF , ainsd obtain ai gog rr ef f r ac een do yynpp , eeaoo the length o lsy , m l pl dttir et ccef ir x ( er signal’s number ricP ) p g . Ie ian fe s u te C u rP m e se s t if fce su uinw ea aorrfrriiteehrresstaayU ne d rs i t e system model, OFDM signal is cy- ». Dans Network Security and Communication Engineering, 522–23. CRC Press, 2015. http://dx.doi.org/10.1201/b18660-134.
Texte intégralActes de conférences sur le sujet "U-LTS model"
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Lima, Henrique V., Abdallah S. Abdallah, Elivelton F. Bueno et Kleber V. Cardoso. « A Stochastic Programming Model for Resource Allocation in LTE-U Networks ». Dans 2018 IEEE Canadian Conference on Electrical & Computer Engineering (CCECE). IEEE, 2018. http://dx.doi.org/10.1109/ccece.2018.8447780.
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Jiang, Chen, Wenhao Wu et Zhi Ding. « The Design of Transport Block-Based ROHC U-Mode for LTE Multicast ». Dans GLOBECOM 2018 - 2018 IEEE Global Communications Conference. IEEE, 2018. http://dx.doi.org/10.1109/glocom.2018.8648067.
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ROTHBAUER, Rainer J., Gunther GRASBERGER, Zainal ABIDIN et Raimund A. ALMBAUER. « Reed Valve, Crankcase and Exhaust Models Coupled to 3D Fluid Domains for the Predictive CFD Simulation ». Dans Small Engine Technology Conference & Exposition. 10-2 Gobancho, Chiyoda-ku, Tokyo, Japan : Society of Automotive Engineers of Japan, 2007. http://dx.doi.org/10.4271/2007-32-0030.
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<div class="section abstract"><div class="htmlview paragraph">The development and optimization of two stroke engines, especially the development of internal mixture preparation and the combustion process, require effective and reliable simulation in order to shorten the development time and to reduce prototype and test bench costs. CFD (Computational Fluid Dynamics) is a state of the art tool to optimize and visualize the fluid processes, e.g. scavenging, in-cylinder charge motion, spray formation, mixture preparation or combustion. The drawback of full 3D CFD simulation is the required time for grid generation and calculation of the model, especially for the simulations in the early development phase or in the concept phase as the available time for simulation is limited. Additionally, two stroke specific models e.g. for the reed valve, are not available in commercial 3D CFD codes.</div><div class="htmlview paragraph">In previous investigations [SAE <a href="http://www.sae.org/technical/papers/2005-32-0099" target="_blank">2005-32-0099</a>] the strategies and the requirements for a predictive simulation have been discussed. Consequently, a new methodology which bases on the combination of 3-dimensional (3D) and 0/1-dimensional (0/1D) CFD simulation has been presented. This methodology uses a new multidimensional interface technology which has been discussed in [SAE <a href="http://www.sae.org/technical/papers/2006-32-0059" target="_blank">2006-32-0059</a>]. The new interfacing technology is able to handle 3D/3D, 3D/1D or 3D/0D connections. This allows the replacement of regions with typically high numbers of cells by fast-calculating 0D or 1D models in order to reduce the number of 3D cells and therewith computational time.</div><div class="htmlview paragraph">In the present paper these new models and their formulation and validation are presented in detail:</div><div class="htmlview paragraph"><u>Reed valve model:</u> Two different approaches for the simulation of the behavior of the reed petal are developed and compared. The first one describes the reed motion based on a spring - damping system for a single oscillating mass. The second model is based on a bending beam model using the superposition of Eigenmodes. These models are validated with measurements using a high-speed camera to determine the reed motion shape and lift. Accompanying 3D CFD simulations are used for the visualization of the pressure and mass flow distribution.</div><div class="htmlview paragraph"><u>Exhaust model:</u> For the simulation of the gas dynamics and the heat transfer in the exhaust, a 1D simulation tool using a 2<sup>nd</sup> order Total Variation Diminishing (TVD) solver is developed.</div><div class="htmlview paragraph"><u>Crank case model:</u> The crank case is described by a 0D model of a variable volume with wall heat flux.</div><div class="htmlview paragraph">The exhaust and the crank case models are validated by comparison to commercial 1D CFD codes.</div><div class="htmlview paragraph">The reed valve, the crank case and the exhaust model form a tool box for predictive two stroke engine simulation. This methodology allows adjusting the model in the development process according to the required flow details, accuracy and available simulation time.</div><div class="htmlview paragraph">The discussion about the impact of the tool box on the development work and the comparison to conventional methodology concludes the paper.</div></div>
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leng, Fei, et Ren He. « Compound Brake Control for Improved Ride Comfort for Dual-rotor In-wheel Motor Electric Vehicles ». Dans WCX SAE World Congress Experience. 400 Commonwealth Drive, Warrendale, PA, United States : SAE International, 2023. http://dx.doi.org/10.4271/2023-01-0526.
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<div class="section abstract"><div class="htmlview paragraph">Aiming at the problem of braking shock caused by the inconsistent response time of the inner motor (IM), the outer motor (OM) and the hydraulic brake when the regenerative braking mode of dual-rotor in-wheel motor (DRIWM) is switched, this paper proposes a U-shaped transition coordinated control strategy for the DRIWM. Ensure that the total braking torque can be smoothly transitioned when any one or more of the hydraulic braking torque, the braking torque of the IM and the braking torque of the OM enter/exit braking. The dynamic model of electric vehicle (EV) with DRIWMs is established, the division of braking mode is based on the principle of optimal DRIWM system efficiency, and the U-shaped transition coordinated controller of DRIWM is designed. Finally, two cases of switching the IM single braking mode to hydraulic braking mode and OM and hydraulic coordinated braking mode switching to compound braking mode are taken as examples to verify. The results show that, compared with the braking mode switching process without transition coordinated control, the U-shaped transition coordinated control strategy of the DRIWM proposed in this paper can make the DRIWM complete switching within 0.25s on the basis of the optimal system efficiency, which reduces the impact to 2 m/s<sup>3</sup> and ensures a smooth transition of the total braking torque when switching.</div></div>
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Xue, J. Q., J. P. Huang et J. G. Wei. « Influence of different debonding gap types on mechanical performance of axially loaded CFST stub columns ». Dans IABSE Congress, Nanjing 2022 : Bridges and Structures : Connection, Integration and Harmonisation. Zurich, Switzerland : International Association for Bridge and Structural Engineering (IABSE), 2022. http://dx.doi.org/10.2749/nanjing.2022.1600.
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<p>The mechanical performance of concrete-filled steel tubular (CFST) members could be affected by the debonding gaps between steel tubes and core concrete. In this paper, the finite element models (FEMs) of axially loaded CFST stub columns with different debonding gap types, i.e., circumferential debonding gap (CDG) or spherical-cap debonding gap (SDG), were implemented by ABAQUS. The accuracy of FEMs was verified by test results. The influence of different debonding gap types on the mechanical performance of axially loaded CFST stub columns with the same debonding cross- sectional area was compared by using FEMs. The results showed that compared with SDG, the influence of CDG on the ultimate load-bearing capacity (<i>N</i>u) was larger and on the failure mode was smaller. With an increase in CDG arc-length ratio (<i>R</i>CDG), the reduction coefficient of <i>N</i>u (<i>K</i>D) firstly increased and then decreased. With an increase in SDG ratio (<i>χ</i>SDG), the <i>K</i>D decreased. With an increase in <i>R</i>CDG or <i>χ</i>SDG, the <i>N</i>u decreased. All the debonding specimens showed inward buckling in steel tubes within the debonding range, while the outward lateral deflection towards the no- debonding range was also observed. With an increase in <i>R</i>CDG, the inward buckling of steel tubes was more severely to contact with the core concrete at the middle-height of columns, then an outward buckling was found. With an increase in <i>χ</i>SDG, the inward buckling of steel tubes become more significant, but the failure modes remained unchanged.</p>
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Nazari, Sobhan T., Feng Zhu, John Makrygiannis, Jimmy Zhang et Yu-Wei Wang. « Springback Control through Post-stretching Using Different Hybrid Bead Designs with Tonnage Consideration ». Dans WCX SAE World Congress Experience. 400 Commonwealth Drive, Warrendale, PA, United States : SAE International, 2024. http://dx.doi.org/10.4271/2024-01-2859.
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<div class="section abstract"><div class="htmlview paragraph">Multiple hybrid bead designs were investigated in this study to control the springback on DP780 samples using post-stretching technique. The performance of the four different hybrid bead designs was evaluated by measuring the minimum blank-lock tonnage required to control the springback during a U-channel stamping process. A finite element (FE) model of the U-channel stamping process was developed to simulate the process and predict the minimum blank-lock tonnage required for springback control using each of the hybrid bead designs. It is shown that the developed FE model predicts both the required minimum blank-lock tonnage for post-stretching, and the springback profile, with good accuracy.</div></div>
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Hauptman, J. G., H. I. Hassouna, J. A. Penner, T. G. Bell et T. E. Emerson. « ANTITHROMBIN-III SUPPLEMENTATION ATTENUATES DISSEMINATED INTRAVASCULAR COAGULATION IN THEE.COLI ENDOTOXEMIC DOG MODEL ». Dans XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1644890.
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We reported previously that disseminated intravascular coagulation (DIC) occurs early during E. coli endotoxemia in the rat, before the development of serious cardiovascular, metabolic or biochemical abnormalities, and that pretreatment with large doses of purified human antithrombin-III (AT-III; 250 U/kg) markedly attenuates DIC and increases survival (PC0.05). The present study was an extension ofan earlier one in which pretreatment of dogs with a low dose ofhuman AT-III (50 U/kg) provided borderline protection against DIC during endotoxemia. In the present study, mongrel dogs were anesthetized with sodium pentobarbital, continuously monitored over a 21 hour protocol and given full fluid support. Twenty-three dogs were given iv infusions of E. coli endotoxin (0.5mg/kg) at times zero and 15 hours. Of these, seven received iv infusions of purified human AT-III (250 U/kg) 30 minutes prior to endotoxin; 16 received no AT-III and served as controls. Comparing the AT-III treated with the control group, there was significantimprovement in the activated partial thromboplastin time and prothrombin time (P<0.05). Also, fibrinogenand fibrin degradation products were improved significantly in the AT-III treated group (P<0.05). Platelet counts decreased in both groups and there was no between group difference (P>0.05). There was no s i gni fi cant between group differences in other parameters (e.g. hemodynamic, acid-base, metabolic). These data are in agreement with earlier studies in the endotoxemic rat which show that ore occurs early in endotoxemia, that DIC occurs before the development of serious abnormalities in other systems and that AT-III supplementation significantly attenuates OIC. This study supports the hypothes1s that AT-III supplementation is efficacious in conditions of impending OIC such as gram-negative endotoxemia/septicemia.
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Padthe, Ashwani, Mark Lopez, Ondrej Juhasz, Emily Glover, Tom Berger et Eric Tobias. « Design, Modeling, and Flight Dynamics Analysis of Generic Lift-Offset Coaxial Rotor Configurations ». Dans Vertical Flight Society 78th Annual Forum & Technology Display. The Vertical Flight Society, 2022. http://dx.doi.org/10.4050/f-0078-2022-17580.
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Lift-offset coaxial compound rotorcraft designs have been proposed for the U. S. Army Future Vertical Lift (FVL) programs. Without a need for the tail rotor and equipped with a pusher-propeller, the coaxial compound configuration is capable of achieving high airspeeds and perform maneuvers not feasible for the conventional rotorcraft. To facilitate an independent assessment of the lift-offset coaxial configurations by the U. S. Army, two designs are presented in this paper. Physics-based flight dynamic models are developed using open source data and implemented into the HeliUM-A comprehensive analysis code. On-axis frequency responses from the models are validated against available flightdata showing good agreement. The models are trimmed for a range of vehicle airspeeds, pitch angles, and rotor speeds. Trends in trim controls, hub loads, and power consumption are studied. Linearized time-invariant (LTI) models are extracted from the nonlinear HeliUM-A models. The LTI models are used to study trends in system eigenvalues, stability and control derivatives. Vehicle flight dynamics are examined through frequency response plots at various flight conditions.
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Ju, Xiaochen, Xiaogang Liu, Zhibin Zeng et Xinxin Zhao. « Fatigue study on rib-to-deck welded joint considering weld penetration rate ». Dans IABSE Congress, New York, New York 2019 : The Evolving Metropolis. Zurich, Switzerland : International Association for Bridge and Structural Engineering (IABSE), 2019. http://dx.doi.org/10.2749/newyork.2019.0675.
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<p>The U-shaped rib-to-deck welded joint in orthotropic steel deck is a part with multiple fatigue cracks. The penetration rate which is the ratio of penetration depth to U-shaped rib thickness has an important influence on fatigue performance of partial joint penetration (PJP) welds. In this study, the influence of penetration rate on the fatigue performance of U-shaped rib-to-deck welded joints was studied. Firstly, the finite element model of U-shaped rib-to-deck welded joints with penetration rate of 65%, 75%, 85% and complete joint penetration (CJP) welds were established. The mechanical characteristics of different welding forms under typical loading conditions were analyzed. It was found that with the increase of penetration rate of PJP welds, the stress concentration at the weld root weakened. Then fatigue tests on specimens with different weld penetration rate were carried out. The fatigue cracks of CJP welds all started at the inner welding toe of the U-shaped rib. However, the fatigue cracks of PJP welds mainly started at the welding root of the unfused weld. Fatigue S-N curves for PJP and CJP were regressed, respectively, it could be found that the fatigue performance of CJP welds was superior to that of PJP welds.</p>
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Deng, Lu, An Zhang et Ran Cao. « Pixel-level Road Crack Detection and Segmentation Based on Deep Learning ». Dans IABSE Congress, Nanjing 2022 : Bridges and Structures : Connection, Integration and Harmonisation. Zurich, Switzerland : International Association for Bridge and Structural Engineering (IABSE), 2022. http://dx.doi.org/10.2749/nanjing.2022.1346.
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<p>This paper proposed an integrated framework for detecting and segmenting road cracks in complex backgrounds. Based on the latest real-time object detection algorithm, YOLOv5l6, a modified U-Net embedded Bottleneck and Attention mechanism modules was developed to segment crack pixels from the detected crack regions. Validation of the proposed approach was conducted based on a total of 150 images, which were taken from different backgrounds, angles, and distances. Based on the computation, the results derived from the YOLOv5l6-based crack detection had a mean average precision of 92%, and the mean intersection of the union of the modified U-Net was 87%, which is at least 11% higher than the original U-Net model. The results showed the integrated approach could be a potential basis for an automated road-condition evaluation scheme for road operation and maintenance.</p>
Rapports d'organisations sur le sujet "U-LTS model"
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Knight, R. D., B. A. Kjarsgaard, E G Potter et A. Plourde. Uranium, thorium, and potassium analyses using pXRF spectrometry. Natural Resources Canada/CMSS/Information Management, 2021. http://dx.doi.org/10.4095/328973.
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The application of portable XRF spectrometry (pXRF) for determining concentrations of uranium (U), thorium (Th) and potassium (K) was evaluated using a combination of 12 Certified Reference Materials, 17 Standard Reference Materials, and 25 rock samples collected from areas of known U occurrences or mineralization. Samples were analysed by pXRF in Soil, Mining Cu/Zn and Mining Ta/Hf modes. Resulting pXRF data were compared to published recommended values, obtained by total or near total digestion methods with ICP-MS and ICP-OES analysis. Results for pXRF show a linear relationship, for thorium, potassium, and uranium (&lt;5000 ppm U) as compared to the recommended concentrations. However, above 5000 ppm U, pXRF results show an exponential relationship with under reporting of pXRF concentrations compared to recommended values. Accuracy of the data can be improved by post-analysis correction using linear regression equations for potassium and thorium, and samples with &lt;5000 ppm uranium; an exponential correction curve is required at &gt;5000 ppm U. In addition, pXRF analyses of samples with high concentrations of uranium (e.g. &gt;1 wt.% U) significantly over-estimated potassium contents as compared to the published values, indicating interference between the two elements not calibrated by the manufacturer software.
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Neudecker, Denise, Amy Lovell et Patrick Talou. Producing ENDF/B-quality Evaluations of <sup>239</sup>Pu(n,f) and <sup>235</sup>U(n,f) Average Prompt Neutron Multiplicities using the CGMF Model. Office of Scientific and Technical Information (OSTI), octobre 2021. http://dx.doi.org/10.2172/1897963.
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