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921.
Seung-Jean Kim In-Joong Ha 《Automatic Control, IEEE Transactions on》1999,44(11):2086-2089
It is shown that the differential equation with discontinuous right-hand side, which describes the dynamic behavior of a mechanical system with friction, has a Caratheodory solution. This result supports theoretically the prior work on the control of mechanical systems with friction, which assumes the existence of Caratheodory solutions without proof 相似文献
922.
J.-M. André K. Le GuenP. Jonnard Y. Ménesguen 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2011,659(1):318-321
A detector system, called DUVEX, has been developed for the soft-x-ray and extreme ultraviolet domain. It consists of a YAG:Ce scintillator coupled to a photomultiplier module working under vacuum in counting mode. The design and the performances of this detector in terms of yield, absolute efficiency, response and noise are reported. Spectra in the soft x-ray range of different elements (W, Ag, Al, Mg, Cu, N, C and B) obtained in WDS mode using this detector are presented. DUVEX appears as a competitive detection tool in terms of cost and easiness of implementation. 相似文献
923.
Zhiyuan Chen Le Dinh Van Khoa Ee Na Teoh Amril Nazir Ettikan Kandasamy Karuppiah Kim Sim Lam 《Knowledge and Information Systems》2018,57(2):245-285
Money laundering has been affecting the global economy for many years. Large sums of money are laundered every year, posing a threat to the global economy and its security. Money laundering encompasses illegal activities that are used to make illegally acquired funds appear legal and legitimate. This paper aims to provide a comprehensive survey of machine learning algorithms and methods applied to detect suspicious transactions. In particular, solutions of anti-money laundering typologies, link analysis, behavioural modelling, risk scoring, anomaly detection, and geographic capability have been identified and analysed. Key steps of data preparation, data transformation, and data analytics techniques have been discussed; existing machine learning algorithms and methods described in the literature have been categorised, summarised, and compared. Finally, what techniques were lacking or under-addressed in the existing research has been elaborated with the purpose of pinpointing future research directions. 相似文献
924.
925.
A. Lawani J. Le Meur Dmitrii Tayurskii A. El Kaabouchi L. Nivanen B. Minisini F. Tsobnang M. Pezeril A. Le Méhauté Q. A. Wang 《Journal of Low Temperature Physics》2008,150(3-4):605-611
In the Bose-Einstein condensation of interacting atoms or molecules such as 87Rb, 23Na and 7Li, the theoretical understanding of the transition temperature is not always obvious due to the interactions or zero point
energy which cannot be exactly taken into account. The S-wave collision model fails sometimes to account for the condensation
temperatures. In this work, we look at the problem within the nonextensive statistics which is considered as a possible theory
describing interacting systems. The generalized energy U
q
and the particle number N
q
of boson gas are given in terms of the nonextensive parameter q. q>1 (q<1) implies repulsive (attractive) interaction with respect to the perfect gas. The generalized condensation temperature T
cq
is derived versus T
c
given by the perfect gas theory. Thanks to the observed condensation temperatures, we find q≈0.1 for 87Rb atomic gas, q≈0.95 for 7Li and q≈0.62 for 23Na. It is concluded that the effective interactions are essentially attractive for the three considered atoms, which is consistent
with the observed temperatures higher than those predicted by the conventional theory.
相似文献
926.
Alumina-based macro-porous ceramic foams were successfully coated with MCM-41 meso-porous materials using an in-situ one step hydrothermal synthesis. Low H2O/NaOH ratio in the starting mixture leads to a not uniform deposition of the meso-porous materials. Using higher H2O/NaOH ratio and two cycles of deposition, a CF with a continuous and thick layer of well-ordered MCM-41 material coating was produced. 相似文献
927.
大型长廊阻抗式调压室三维非线性数值分析 总被引:1,自引:0,他引:1
采用三维非线性有限元分析方法,结合泸定水电站调压室的开挖,模拟了大型长廊阻抗式调压室开挖和支护的施工过程。利用改进的锚杆单元模拟支护结构中锚杆的作用。分别从围岩稳定和衬砌结构的受力特性两个方面对调压室进行了分析,给出了围岩支护和结构设计的基本分析方法.可为类似工程提供借鉴。 相似文献
928.
C Sanz Y León J Troppmair UR Rapp I Varela-Nieto 《Canadian Metallurgical Quarterly》1999,18(2):429-437
Regulation of organogenesis involves a dynamic balance of the mechanisms regulating cell division, differentiation and death. Here we have investigated the pattern of expression of c-Raf kinase in the inner ear during early developmental stages and the consequences of manipulating c-Raf levels by misexpression of c-raf viral vectors in organotypic cultures of otic vesicle explants. We found that otic vesicles expressed c-Raf and its level remained constant during embryonic days 2 and 3 (E2-E3). c-Raf activity was increased in response to insulin like growth factor-I (IGF-I) and the activation by IGF-I of the c-Raf kinase pathway was a requirement to turn on cell proliferation in the otic vesicle. Overexpression of c-raf in E2.5 explants increased the proliferative response to low serum and IGF-I and blocked differentiation induced by retinoic acid. The increase in c-Raf levels also prevented nerve growth factor (NGF)-dependent induction of programmed cell death. Consistent with these results, the expression of a dominant negative c-Raf mutant potentiated retinoic acid action and decreased the rate of cell proliferation. We conclude that a strict control of c-Raf levels is essential for the co-ordination of the biological processes that operate simultaneously during early inner ear development. 相似文献
929.
G. Clotuche G. Le Goff A-C Mailleux J-L Deneubourg C. Detrain T. Hance 《Microscopy research and technique》2009,72(9):659-664
Tetranychus urticae (Acari: Tetranychidae) is a phytophagous mite that forms colonies of several thousand individuals. Like spiders, every individual produces abundant silk strands and is able to construct a common web for the entire colony. Despite the importance of this silk for the biology of this worldwide species, only one previous study suggested how to visualize it. To analyze the web structuration, we developed a simple technique to dye T. urticae'silk on both inert and living substrates. Fluorescent brightener 28 (FB) (Sigma F3543) diluted in different solvents at different concentrations regarding the substrate was used to observe single strands of silk. On glass lenses, a 0.5% dimethyl sulfoxide solution was used and on bean leaves, a 0.1% aqueous solution. A difference of silk deposit was observed depending the substrate: rectilinear threads on glass lenses and more sinuous ones on bean leaves. This visualizing technique will help to carry out future studies about the web architecture and silk used by T. urticae. It might also be useful for the study of other silk-spinning arthropods. Microsc. Res. Tech. 2009. © 2009 Wiley-Liss, Inc. 相似文献
930.
An Impulse-time Perturbation Approach for a Symmetric Extra-insensitive Input Shaper 总被引:1,自引:0,他引:1
Ha Chang-Wan Lee Dongwook Rew Keun-Ho Kim Kyung-Soo 《International Journal of Control, Automation and Systems》2018,16(3):1239-1246
International Journal of Control, Automation and Systems - In this study, symmetric perturbation extra-insensitive input shapers (SPEI-ISs) are proposed to enhance the robustness of the... 相似文献