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直升机传动系统的研制,需要大量试车台对其设计合理性进行试验验证。在满足传动系统试车台技术指标的基础上,采用分布式结构和C/S模式测控网络,设计了一种具有通用性的测控系统。详细阐述了测控系统工作原理和软硬件设计。该系统减少了试车台建设和适应性改造的周期和难度,增强试车台的灵活性和可维护性。系统已成功应用于多个传动系统试车台,且运行稳定可靠。 相似文献
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We show theoretically and confirm experimentally that frequency characteristics of the system of a diaphragm and a short-circuit plunger can be determined primarily by one of higher-order modes. Making salients and hollows whose numbers in the slot correspond to indices of this mode leads to a significant (by a factor of about 2) decrease in the resonance-curve width. 相似文献
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Deborah Fowler Garrett Lopp Dhiraj Bansal Ryan Schultz Matthew Brake Micah Shepherd 《声与振动》2018,52(3):12-17
Acoustoelastic coupling occurs when a hollow structure’s in-vacuo mode aligns with an acoustic mode of the internal cavity. The impact of this coupling on the total dynamic response of the structure can be quite severe depending on the similarity of the modal frequencies and shapes. Typically, acoustoelastic coupling is not a design feature, but rather an unintended result that must be remedied as modal tests of structures are often used to correlate or validate finite element models of the uncoupled structure. Here, however, a test structure is intentionally designed such that multiple structural and acoustic modes are well-aligned, resulting in a coupled system that allows for an experimental investigation. First, coupling in the system is identified using a measure termed the magnification factor. Next, the structural-acoustic interaction is measured. Modifications to the system demonstrate the dependency of the coupling on changes in the mode shape and frequency proximity. This includes an investigation of several practical techniques used to decouple the system by altering the internal acoustic cavity, as well as the structure itself. These results show that acoustic absorption material effectively decoupled the structure while structural modifications, in their current form, proved unsuccessful. Readily available acoustic absorptive material was effective in reducing the coupled effects while presumably adding negligible mass or stiffness to the structure. 相似文献
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Dynamical System Approach to a Coupled Dispersionless System: Localized and Periodic Traveling Waves
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Gambo Betchewe Kuetche Kamgang Victor Bouetou Bouetou Thomas Timoleon Crepin Kofane 《中国物理快报》2009,26(6):55-57
We investigate the dynamical behavior of a coupled dispersionless system describing a current-conducting string with infinite length within a magnetic field. Thus, following a dynamical system approach, we unwrap typical miscellaneous traveling waves including localized and periodic ones. Studying the relative stabilities of such structures through their energy densities, we find that under some boundary conditions, localized waves moving in positive directions are more stable than periodic waves which in contrast stand for the most stable traveling waves in another boundary condition situation. 相似文献
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LIU Chun-hao GUO Jin-jia YE Wang-quan LIU Qing-sheng LI Nan ZHENG Rong-er 《光谱学与光谱分析》2018,38(12):3753-3757
水下激光诱导击穿光谱技术(LIBS)和水下激光拉曼光谱技术(Raman)已在深海成功获得应用,这两种技术探测对象互补、器件类似,两者联合探测可更好的进行深海研究。针对此需求研发了一套LIBS-Raman光谱联合水下原位探测原理样机,整个系统集成于L790 mm×Φ270 mm的舱体内,在舱体前端有光学窗口和水密插头,舱体内部主要包括脉冲激光器、光谱仪、嵌入式计算机和供电转换装置,甲板控制终端通过水密电缆实现对系统的供电、控制和数据采集。该联合系统采用一台双波长脉冲激光器同时作为LIBS和拉曼光谱的激发光源,LIBS采用1 064 nm波长,拉曼光谱采用532 nm波长。双波长激光器发出的光束经分光镜分为两路,经过后向散射光路收集的两路信号分别进入两个小型光纤光谱仪进行分光探测,LIBS采用AvaSpec-ULS2048光谱仪,拉曼光谱采用QE 65000光谱仪。利用搭建的原理样机在青岛近海进行水下原位探测,在实验室开展了水中固体靶的探测,实验结果证明了LIBS-Raman联合光谱探测装置的可行性。下一步将优化系统并开展深海探测应用。 相似文献
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We reveal resonant reflection in a microstrip system with an iris and a short-circuit plunger for distances between the iris
and the plunger that are much less than the wavelength in the transmission line. It is shown that the studied system can be
used for design of novel microwave devices, including semiconductor ones, with controllable characteristics and decreased
sizes.
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Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 48, No. 5, pp. 402–405, May 2005. 相似文献
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An elementary method of conctructing a spinor from vectors satisfying constraint conditions is proposed. We consider orthonormal triad and tetrad as an orientable physical object and introduce parameter representations of them, in terms of the Euler angles and the pseudo-Euler angles. Having determined the transformation property of the parameters, we set up the spinor determining equation. This equation is solved. The solution (spinor) contains four arbitrary complex constants, in 3 + 1 dimensional space. Using the proposed method, we prove the spinor reconstruction theorem, i.e. the original Dirac spinor can be reconstructed from seven of the sixteen hermitian bilinear forms, except the overall phase factor (the gauge freedom of the 1st kind). The energy density of the spinor field is written in terms of currents and their space derivatives. 相似文献
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We investigate a few features of entanglement of two types of particles coupled through a nonlinear interaction. It is shown that the entanglement created by the nonlinear interaction can reflect nonlinearity of the system. Possible observation of our prediction in a double-well trapped Bose-Einstein condensate is discussed. 相似文献
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Using a measure for the divisibility of a dynamical map, we study the non-Markovian character of a quantum evolution of a spin-S system, which is in an external field and weakly coupled to a bosonic bath with a certain temperature. The finite-temperature dynamics of the open system is obtained by the time-convolutionless master equation in the secular approximation. Besides the influence of the environmental spectral density function, the external field and low temperatures can affect the quantum non-Markovianity. It is found out that the non-Markovian feature of a dynamical map of a high-dimensional spin system is noticeable in contrast to that of a low-dimension spin system. 相似文献
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ZHANG Xiao-Dan SHI Feng WANG Zhen 《理论物理通讯》2007,48(2):267-274
This article introduces a new chaotic system of three-dimensional quadratic autonomous ordinary differential equations, which can display different attractors with two unstable equilibrium points and four unstable equilibrium points respectively. Dynamical properties of this system are then studied. Furthermore, by applying the undetermined coefficient method, heteroclinic orbit of Shil'nikov's type in this system is found and the convergence of the series expansions of this heteroclinic orbit are proved in this article. The Shil'nikov's theorem guarantees that this system has Smale horseshoes and the horseshoe chaos. 相似文献
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Information transmission and storage have gained traction as unifying concepts to characterize biological systems and their chances of survival and evolution at multiple scales. Despite the potential for an information-based mathematical framework to offer new insights into life processes and ways to interact with and control them, the main legacy is that of Shannon’s, where a purely syntactic characterization of information scores systems on the basis of their maximum information efficiency. The latter metrics seem not entirely suitable for biological systems, where transmission and storage of different pieces of information (carrying different semantics) can result in different chances of survival. Based on an abstract mathematical model able to capture the parameters and behaviors of a population of single-celled organisms whose survival is correlated to information retrieval from the environment, this paper explores the aforementioned disconnect between classical information theory and biology. In this paper, we present a model, specified as a computational state machine, which is then utilized in a simulation framework constructed specifically to reveal emergence of a “subjective information”, i.e., trade-off between a living system’s capability to maximize the acquisition of information from the environment, and the maximization of its growth and survival over time. Simulations clearly show that a strategy that maximizes information efficiency results in a lower growth rate with respect to the strategy that gains less information but contains a higher meaning for survival. 相似文献
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《Journal of Nonlinear Mathematical Physics》2013,20(1-2):114-116
Abstract The Lie and Q-conditional invariance of one nonlinear system of PDEs of the third-order is searched. The ansatze have been built which reduce the PDEs system to ODEs. The classes of exact solutions of the given system are obtained. The relation between the Korteweg-de Vries equation and Harry-Dym equation has been established. 相似文献
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G.I. Menon 《Phase Transitions》2013,86(4-5):477-486
Recent progress in the understanding of the phase behaviour of disordered type-II superconductors is discussed in the context of three studies. The first describes a physically appealing picture of correlations in the "vortex glass" or "pinned liquid" phase in BSCCO; calculations based on this picture agree well with experimental data from muon-spin-rotation experiments. The second details a new proposal for the phase behaviour of disordered low-T c materials. In the third, a universal phase diagram for all disordered type-II superconductors is proposed. The attributes of this phase diagram are discussed briefly and the experimental, theoretical and simulational evidence in its favour summarized. 相似文献
18.
Using a measure for the divisibility of a dynamical map,we study the non-Markovian character of a quantum evolution of a spin-S system,which is in an external field and weakly coupled to a bosonic bath with a certain temperature.The finite-temperature dynamics of the open system is obtained by the time-convolutionless master equation in the secular approximation.Besides the influence of the environmental spectral density function,the external field and low temperatures can afect the quantum non-Markovianity.It is found out that the non-Markovian feature of a dynamical map of a high-dimensional spin system is noticeable in contrast to that of a low-dimension spin system. 相似文献
19.
We investigate the bistable properties and the entanglement in a two-mode cavity optomechanical system. Our results show that the bistable regime in terms of pumping amplitude can be adjusted by tuning the detunning. Although the two modes of the cavity interact with the same mechanical mode, there is no entanglement between them, while the two modes entangle with the mechanical mode seperately. 相似文献
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Wenyi Shao Yangyang Du Qi Yang Gangcheng Wang Chunfang Sun Kang Xue 《International Journal of Theoretical Physics》2017,56(3):643-651
In this paper, we construct a parameterized form of unitary \(\breve {R}_{123}(\theta _{1},\theta _{2},\varphi )\) matrix through the Yang-Baxterization method. Acting such matrix on three-qubit natural basis as a quantum gate, we can obtain a set of entangled states, which possess the same entanglement value depending on the parameters ?? 1 and ?? 2. Particularly, such entangled states can produce a set of maximally entangled bases Greenberger-Horne-Zeilinger (GHZ) states with respect to ?? 1 = ?? 2 = π/2. Choosing a useful Hamiltonian, one can study the evolution of the eigenstates and investigate the result of Berry phase. It is not difficult to find that the Berry phase for this new three-qubit system consistent with the solid angle on the Bloch sphere. 相似文献