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辽河辽宁段线性文化遗产景观体系构建

山西建筑 2025年第03期51卷 13-16+37页

作者：田佳宁王琳大连工业大学

辽河有着丰富的自然资源和璀璨的人文资源，深入挖掘辽河文化价值，促进文化遗产保护传承，推动辽河文化产业带建设是推动东北全面振兴的重要举措。从时间、空间双维度叠合的方法入手，通过定位、定区、定点的系统思路，逐级对辽河辽宁... 详细信息

辽河有着丰富的自然资源和璀璨的人文资源，深入挖掘辽河文化价值，促进文化遗产保护传承，推动辽河文化产业带建设是推动东北全面振兴的重要举措。从时间、空间双维度叠合的方法入手，通过定位、定区、定点的系统思路，逐级对辽河辽宁段的自然资源和人文资源进行重新整合，构建文化遗产景观体系，并提出具体建设策略，以期为辽河的保护与发展提供新的思路，也为相关的线性文化遗产等方面的研究提供研究思路与研究方法。

关键词：线性文化遗产景观体系构建辽河辽宁段遗产保护

Numerical investigation of low cycle fatigue life for channel wall nozzles

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航空动力学报 2018年第7期33卷 1553-1565页

作者： cheng cheng WANG Yibai LIU Yu lin Qingguo Research and Development Center Shanghai Institute of Space Propulsion Shanghai 201112 China Shanghai Engineering Research Center of Space Engine Shanghai 201112 China School of Astronautics Beijing University of Aeronautics and Astronautics

The thermal-structural response and low cycle fatigue life of a three-dimensional(3D)channel wall nozzle with regenerative cooling were numerically investigated by coupling the finite volume fluid-thermal method,nonlinear finite element thermal-structural analysis and local strain *** nozzle had a high area ratio(nozzle exit area divided by throat area)under cyclic working *** studies were carried out to evaluate the effects of channel structural parameters such as channel width,channel height,liner thickness and rib *** showed that the integrated effects of three-dimensional channel structure and load distribution caused serious strain,which mainly occurred at the intersectant regions of liner wall on the gas side and the symmetric planes of channel and *** cooling effect and channel structural strength were significantly improved as the channel width and height decreased,leading to substantial extension of the nozzle service *** the other hand,the successive decrease in liner thickness and rib width apparently increased the strain amplitude and residual strain of channel wall nozzle during cyclic work,significantly shortening the service *** present work is of value for design of the channel wall nozzle to prolong its cyclic service life.

关键词： liquid propellant rocket engine low cycle fatigue channel wall nozzle regenerative cooling nonlinear structural analysis finite element method

Penile rehabilitation with a vacuum erectile device in an animal model is related to an antihypoxic mechanism： blood gas evidence

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Asian Journal of Andrology 2013年第3期15卷 387-390页

作者： Hao-cheng lin Wen-Li Yang Jun-Lan Zhang Yu-tian Dai Run Wang Department of Urology Affiliated Drum Tower Hospital School of Medicine Nanjing University Nanjing 210008 China Division of Urology University of Texas Medical Schoo at Houston TX 77030 USA Division of Gastroenterology Hepatology & Nutrition Department of Internal Medicine University of Texas Medical School at Houston TX 77030 USA Department of Urology University of Texas MD Anderson Cancer Center Houston TX 77030 USA

Our previous study showed that vacuum erectile device （VED） therapy has improved erectile function in rats with bilateral cavernous nerve crush （BCNC） injuries. This study was designed to explore the mechanism of VED in penile rehabilitation by analyzing cavernous oxygen saturation （SO2） and to examine the effect of VED therapy on preventing penile shrinkage after BCNC. Thirty adult Sprague- Dawley rats were randomly assigned into three groups： group 1, sham surgery; group 2, BCNC; and group 3, BCNC＋VED. Penile length and diameter were measured on a weekly basis. After 4 weeks of therapy, the penile blood was extracted by three methods for blood gas analysis （BGA）： method 1, cavernous blood was aspirated at the flaccid state; method 2, cavernous blood was aspirated at the traction state; and method 3, cavernous blood was aspirated immediately after applying VED. SO2 values were tested by the blood gas analyzer. The results showed that VED therapy is effective in preventing penile shrinkage induced by BCNC （Penile shortening： BCNC group 1.9±1.1 mm; VED group 0.3±1.0 mm; P〈0.01. Penile diameter reduction： BCNC group 0.28±0.14 mm; VED group 0.04±0.14 mm; P〈0.01）. The mean SO2±s.d. values were increased by VED application （88.25%±4.94%） compared to the flaccid （76.53%±4.16%） or traction groups （78.93%±2.56%）（P〈0.05）. The calculated blood constructs in the corpus cavernosum right after VED application were 62% arterial and 38% venous blood. These findings suggest that VED therapy can effectively preserve penile size in rats with BCNC injury. The beneficial effect of VED therapy is related to antihypoxia by increasing cavernous blood SO2.

关键词： blood SO2 erectile dysfunction (ED) penile size vacuum therapy

Effects of mean shear on the vortex identification and the orientation statistics

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Theoretical & Applied Mechanics Letters 2023年第4期13卷 280-286页

作者： tianyi Bai cheng cheng lin Fu Department of Mechanical and Aerospace Engineering The Hong Kong University of Science and TechnologyHong Kong 999077China Department of Mathematics The Hong Kong University of Science and TechnologyHong Kong 999077China HKUST Shenzhen-Hong Kong Collaborative Innovation Research Institute Shenzhen 815057China

This work compares the threshold applied to the swirling strength as well as the vortex orientation statistics in the total and fluctuating velocity fields using direct numerical simulations of compressible and incompressible turbulent channel *** is concluded that the difference in the swirling strength for vortex identification is minimal in the logarithmic region such that these two situations share the same *** the vortex orientation,the inclination angle remains ***,as the wall-normal distance increases,a more and more obvious distinction is noticed for its orientation with respect to the spanwise(z)*** is mainly due to their intrinsic differences and attendant contrasting preference for the vortex identification,i.e.,vortices rotating in the−z direction for the total velocity field and in the z direction for the fluctuating *** observations function as a reasonable explanation for various remarks in previous studies.

关键词： Vortex Compressible wall-bounded turbulence Turbulence structure Channel flows

Coherent Control of a Simple Quantum System

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Chinese Physics Letters 1997年第6期14卷 417-420页

作者： lin Fu-cheng Shanghai Institute of Optics and Fine Mechanics Chinese Academy of SciencesShanghai 201800

The quantum dynamics of a three-level Vee-system can be controlled by using two single-mode cw *** dc component of the probability for finding a specific state in laser fields can be obtained by matching the intensities,phases and detunings of the lasers to relevant eigenvalues of the quantum *** selectivity of control does not depend strongly on the laser intensities but the absolute amount of the product does *** are generally three paths to reach such a dc component control and,at some points,two of them cross each other causing a near 100%*** stability of the process to the fluctuation of the experiment was analyzed.

关键词： tuning quantum Quantum

Microstructure evolution and corrosion behavior of Nb-alloyed cast heat-resistant steel during different aging treatments

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Journal of Iron and Steel Research International 2020年第12期27卷 1456-1465页

作者： Lv-dan Teng tian-tian Zhao Teng-fei cheng Yi-tao Yang School of Materials Science and Engineering Shanghai UniversityShanghai 200444China

The microstructure evolution of heat-resistant cast stainless steels aged at 600, 700, 800 and 900 ℃ for 2 h was investigated by scanning electron microscopy and X-ray diffraction. Potentiodynamic polarization curves were applied to study the effects of Nb addition and aging temperature on corrosion resistance. The results demonstrated that eutectoid decomposition of the ferritic phase (δ → σ + γ2) was observed at 700-900 ℃. The content of σ-phase first increased and then decreased in the steels, where the maximum content was obtained at 800 ℃, indicating that the highest hardness occurred at 800 ℃ accordingly. The hardness of Nb-containing steels was significantly higher than that of Nb-free steels. The corrosion resistance of heatresistant cast steels in various aging temperatures was different due to the formation of σ-phase. Both Cr-rich carbides and σ-phase were harmful to the corrosion resistance, while Cr-rich carbides were the main factor. Nb-containing heat-resistant cast steels exhibited superior corrosion resistance, as Cr-rich carbides were reduced and the corrosion products of Nb-rich slowed down the formation of steady-state pits.

关键词： Nb addition Aging temperature σ-phase Polarization Pitting corrosion

Force-position collaborative optimization of rope-driven snake manipulator for capturing non-cooperative space targets

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Chinese Journal of Aeronautics 2024年第9期37卷 369-384页

作者： Xiaofeng LI Jian tian cheng WEI Xibin CAO School of Astronautics Harbin Institute of TechnologyHarbin 150001China Beijing Instiuteof Spacecraft System Engineering China Academy of Space TechnolgyBeijing 100094Chia

With the rapid development of space activities,non-cooperative space targets increase swiftly,such as failed satellites and upper stages,threating normal spacecrafts *** there are some problems in the capture process,such as excessive collision and fast tumbling of targets,manipulator with redundant Degrees of Freedom(DOFs)can be used to improve the compliance and therefore solve these *** Rope-Driven Snake Manipulator(RDSM)is a combina-tion of hyper-redundant DOFs and better compliance,and therefore it is suitable for capturing *** this paper,a snake manipulator mechanism is designed,and the complete kinematic model and system dynamic model considering RDSM,target and contact is ***,to obtain the configuration of joint with hyper-redundant DOFs,an improved motion dexterity index is pro-posed as the joint motion optimization ***,the force-position collaborative optimization index is designed to adjust active stiffness,and the impedance control method based on the modified index is used to capture the space ***,the proposed force-position collaborative opti-mization method is verified by virtual prototype *** results demonstrate that based on the proposed method,the collision force is reduced by about 25%compared to normal impe-dance control,showing higher safety.

关键词： Capturing non-cooperative spacetargets Rope-driven snakemanipu-lator Force-position collaborative optimization Redundant degrees of free-dom Active stiffness adjustment

Number-phase quantization of a mesoscopic RLC circuit

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Chinese Physics B 2012年第2期21卷 114-116页

作者： Xu cheng-lin Department of Mathematics Yunnan Normal UniversityKunming 650092China

With the help of the time-dependent Lagrangian for a damped harmonic oscillator, the quantization of mesoscopic RLC circuit in the context of a number-phase quantization scheme is realized and the corresponding Hamiltonian operator is obtained. Then the evolution of the charge number and phase difference across the capacity are obtained. It is shown that the number-phase analysis is useful to tackle the quantization of some mesoscopic circuits and dynamical equations of the corresponding operators.

关键词： mesoscopic RLC circuit number-phase quantization Lagrangian function

Interaction of two in-line bubbles of equal size rising in viscous liquid

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Chinese Journal of Chemical Engineering 2020年第1期28卷 54-62页

作者： Zhen tian Xi Li Youwei cheng Lijun Wang College of Chemical and Biological Engineering Zhejiang UniversityHangzhou 310027China

The interaction of bubbles is the key to understand gas–liquid bubbling flow. Two-dimensional axis-symmetry computational fluid dynamics simulations on the interactive bubbles were performed with VOF method,which was validated by experimental work. It is testified that several different bubble interactive behaviors could be acquired under different conditions. Firstly, for large bubbles(d: 4, 6, 8, 10 mm), the trailing bubble rising velocity and aspect ratio have negative correlations with liquid viscosity and surface tension. The influences of viscosity and surface tension on leading bubble are negligible. Secondly, for smaller bubbles(d: 1, 2 mm), the results are complicated. The two bubbles tend to move together due to the attractive force by the wake and the potential repulsive force. Especially for high viscous or high surface tension liquid, the bubble pairs undergo several times acceleration and deceleration. In addition, bubble deformation plays an important role during bubble interaction which cannot be neglected.

关键词： Bubble column reactor Computational fluid dynamics Bubble interaction Bubble rise velocity Volume-of-fluid method Bubble aspect ratio