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可重构分布式天线和反射面辅助的集成传感和通信系统演绎

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延安职业技术学院学报 2024年第3期38卷 101-104页

作者：郭永新张琪延川调频转播台陕西延川717200

集成传感和通信系统(ISAC)是一种通过赋予无线通信传感能力来升级物理系统的解决方案,我们开发了一个可重构分布式天线和反射面(RDARS)辅助的集成传感和通信(ISAC)系统原型。该原型采用可编程元件,根据需求动态调整工作模式,优化信号传... 详细信息

集成传感和通信系统(ISAC)是一种通过赋予无线通信传感能力来升级物理系统的解决方案,我们开发了一个可重构分布式天线和反射面(RDARS)辅助的集成传感和通信(ISAC)系统原型。该原型采用可编程元件,根据需求动态调整工作模式,优化信号传输和传感性能。用户定位功能可靠,且不会对通信速率造成影响。系统可应用于室内导航、智能交通等领域,并展示了在6G系统中的潜在应用,为未来需要同时进行通信和传感的应用提供了重要的技术支持和创新思路。

关键词：可重构分布式天线反射面(RDARS) 集成传感和通信系统(ISAC) 定位

Lie Symmetrical Perturbation and Adiabatic Invariants of Generalized Hojman Type for Relativistic Birkhoffian Systems

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Communications in Theoretical Physics 2007年第1期47卷 25-30页

作者： LUO Shao-Kai guo yong-xin Institute of Mathematical Mechanics and Mathematical Physics Zhejiang Sci-Tech University Hangzhou 310018 China Depaxtment of Physics Liaoning University Shenyang 110036 China

For a relativistic Birkhoffian system, the Lie symmetrical perturbation and adiabatic invariants of generalized Bojman type are studied under general infinitesimal transformations. On the basis of the invariance of relativistic Birkhotfian equations under general infinitesimal transformations,Lie symmetrical transformations of the system are constructed, which only depend on the Birkhoffian variables. The exact invariants in the form of generalized Hojman conserved quantities led by the Lie symmetries of relativistic Birkhoffian system without perturbations are given. Based on the definition of higher-order adiabatic invariants of a mechanical system, the perturbation of Lie symmetries for relativistic Birkhoffian system with the action of small disturbance is investigated, and a new type of adiabatic invariants of the system is obtained. In the end of the paper, an example is given to illustrate the application of the results.

关键词： relativity BirkhofIian system Lie symmetrical perturbation exact invariant adiabatic invariant of generalized Hojman type

Routh Order Reduction Method of Relativistic Birkhoffian Systems

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Communications in Theoretical Physics 2007年第2期47卷 209-212页

作者： LUO Shao-Kai guo yong-xin Institute of Mathematical Mechanics and Mathematical Physics Zhejiang Sci-Tech University Hangzhou 310018 China Department of Physics Liaoning University Shenyang 110036 China

Routh order reduction method of the relativistic Birkhoffian equations is studied. For a relativistic Birkhoffian system, the cyclic integrals can be found by using the perfect differential method. Through these cyclic integrals, the order of the system can be reduced. If the relativistic Birkhoffian system has a cyclic integral, then the Birkhoffian equations can be reduced at least by two degrees and the Birkhoffian form can be kept. The relations among the relativistic Birkhoffian mechanics, the relativistic Hamiltonian mechanics, and the relativistic Lagrangian mechanics are discussed, and the Routh order reduction method of the relativistic Lagrangian system is obtained. And an example is given to illustrate the application of the result.

关键词： relativity Birkhoffian system Lagrangian system cyclic integral order reduction method

国内外麻醉深度脑电监测设备的现状与发展展望

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医疗卫生装备 2024年第6期45卷 105-112页

作者：任红郭永馨曹江北解放军总医院第一医学中心北京100039

介绍了国内外麻醉深度脑电监测设备的分类、原理及发展现状,分析了麻醉深度脑电监测设备的应用情况及其优缺点,指出了利用多模态监测技术和人工智能技术、提高患者舒适性和安全性、实现数据共享和跨学科合作等是麻醉深度脑电监测设备未... 详细信息

介绍了国内外麻醉深度脑电监测设备的分类、原理及发展现状,分析了麻醉深度脑电监测设备的应用情况及其优缺点,指出了利用多模态监测技术和人工智能技术、提高患者舒适性和安全性、实现数据共享和跨学科合作等是麻醉深度脑电监测设备未来的发展趋势。

关键词：麻醉深度脑电监测设备麻醉深度麻醉深度监测脑电图监测多模态监测

EXPERIMENTAL STUDY HYDRAULIC ROUGHNESS FOR KAN TIN MAIN DRAINAGE CHANNEI IN HONG KONG

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Journal of Hydrodynamics 2012年第5期24卷 776-784页

作者： WANG Tao YANG Kai-lin guo xing-lei XIE Sheng-zong FU Hui guo yong-xin State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower ResearchBeijing 100038China

The Kam Tin Main Drainage Channel （KTMDC） is an important river for the city drainage in Hong Kong. The roughness and its variations have an obvious effect on the flood control capacity and the flow capacity. So physical model tests are designed to study the KTMDC. Due to its complex channel structure, the tests are completed in two steps. In Step 1, the energy loss is measured along the main channel without inflows, with all inflows and outflows being sealed. In Step 2, all the inflow and outflow structures are measured, with the sealed inflows and outflows being opened on the basis of Step 1. In each step, two schemes are employed. One of the key issues is the choice of suitable materials to make the model＇s roughness similar to that of the prototype. According to the gravity similarity criterion, the 1：25 scale model is built, with the main channel made of Perspex. The facing slopes of the grasscrete and the stone masonry need to be roughened. A kind of the nylon net is selected to simulate the roughness of the stone masonry and the plastic lawn for the grasscrete facing slope. For the different structure reaches, the roughness coefficients are estimated based on the hydraulic theory. The rationality of the test results is verified in this study. The results of testing can provide a reliable basis for the renovation, the expansion, the optimization of this channel.

关键词： roughness hydraulic character channel facing slope grasscrete masonry

Conformal Invariance and Noether Conserved Quantities of First-Order Lagrange Systems

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Communications in Theoretical Physics 2008年第11期50卷 1065-1068页

作者： LIU Chang ZHU Na MEI Feng-Xiang guo yong-xin Department of Mechanics Faculty of Science Beijing Institute of Technology Beijing 100081 China College of Science Dalian Fisheries University Dalian 116023 China College of Physics Liaoning University Shenyang 110036 China

In this paper the conformal invariance by infinitesimal transformations of first-order Lagrange systems is discussed in detail. The necessary and sumeient conditions of conformal invariance by the action of infinitesimal transformations being Lie symmetry simultaneously are given. Then we get the conserved quantities of conformal invariance by the infinitesimal transformations. Finally an example is given to illustrate the application of the results.

关键词： first-order Lagrange systems infinitesimal transformations conformal invariance Noether conserved quantities

Incubation and development of corrosion in microstructures of low alloy steels under a thin liquid film of NaCl aqueous solution

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International Journal of Minerals,Metallurgy and Materials 2010年第6期17卷 748-755页

作者： Wen-hua Zhang Shan-wu Yang Jia guo Zhi-yong Liu xin-lai He School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

Electrochemical measurement, optical microscopy, and scanning electron microscopy were employed to investigate the corrosion behavior of some low alloy steels. The steels were held under a thin liquid film of 0.5wt% NaCl aqueous solution. It is found that the steels with the same chemical composition but different micmstructures exhibit obviously different corrosion behaviors. However, the corrosion behavior of the steels with different compositions but the same microstructnres may be similar in the present investigation. The corrosion rate of bainite is slower than that of ferrite and pearlite. The corrosion products of bainite are uniform and fine. The size of carbon-rich phases produces a great impact on the corrosion of the steels, whether in the initial stage or in the long tenn. It is easy to induce large pitting for carbon-rich phases with large size, which damages the compactness of the rust layer.

关键词： alloy steel microstructure atmospheric corrosion liquid films scanning electron microscope

Riemann-Cartan空间中的d’Alembert-Lagrange原理

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物理学报 2005年第12期54卷 5517-5520页

作者：王勇郭永新广东医学院基础学院东莞523808 辽宁大学物理系沈阳110036

将Kleinert提出的不可积映射推广为一阶线性映射.通过这种方法,将Riemann-Cartan空间嵌入到欧氏空间.在此基础上,将通常在欧氏空间中描述约束系统的d’Alembert-Lagrange原理推广到Riemann-Cartan空间的“无约束”表示.

关键词：一阶线性映射 Riemann-Cartan空间挠率 d'Alembert-Lagrange原理

Rim^(18)F-fluorodeoxyglucose uptake of hepatic cavernous hemangioma on positron emission tomography/computed tomography:A case report

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World Journal of Clinical Cases 2024年第13期12卷 2243-2247页

作者： yong-An Hu Ya-xin guo Qi-Feng Huang Department of Nuclear Medicine Jinhua Hospital of Zhejiang UniversityJinhua Municipal Central HospitalJinhua 321000Zhejiang ProvinceChina

BACKGROUND Peripheral FDG accumulation in a hepatic hemangioma presenting in a patient with prolonged fever is ***,clinicians should pay close attention to patients with hepatic *** SUMMARY A 54-year-old woman with a 4-wk history of daily fevers was admitted to our hospital.A whole body^(18)-Fluordesoxyglucose(PET-FDG)positron emission tomography/computed tomography(PET/CT)was performed to elucidate the source of the ***,whole body^(18)-FDG PET/CT raised the suspicion of a malignant lesion because of peripheral FDG accumulation(SUVmax 3.5 g/mL)higher than that of the normal liver parenchyma(SUVmax 1.6 g/mL)surrounding a hypoactive area,and no other abnormalities were ***,the patient underwent liver mass *** showed a hepatic cavernous hemangioma with fatty infiltration around the *** fever disappeared four days after surgery and the patient did not present any complications during *** Fatty infiltration in the peripheral parts of hepatic cavernous hemangioma may lead to subacute inflammation which further activate the Kupffer *** may cause prolonged fever and peripheral rim FDG accumulation on PET/CT.

关键词： ^(18)-Fluordesoxyglucose positron emission tomography/computed tomography Hepatocellular carcinoma Fever Fatty infiltration Case report