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白噪声海浪激励下船舶非线性横摇运动的概率分析(英文)

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船舶力学 2006年第3期10卷 17-25页

作者：谷家扬江苏科技大学船舶与海洋工程学院江苏镇江212003

应用求解FPK方程近似解的一种新理论研究白噪声激励下船舶非线性横摇运动的联合概率密度函数及稳定期望穿阈率。船舶随机横摇运动微分方程考虑到阻尼力与恢复力的非线性。新理论基于减少FPK方程的误差以获得参数化的联合概率密度函数。... 详细信息

应用求解FPK方程近似解的一种新理论研究白噪声激励下船舶非线性横摇运动的联合概率密度函数及稳定期望穿阈率。船舶随机横摇运动微分方程考虑到阻尼力与恢复力的非线性。新理论基于减少FPK方程的误差以获得参数化的联合概率密度函数。应用本理论易得一维积分表达的系统响应的概率特性,如联合概率密度函数及稳定期望穿阈率。近似解与精确解的比较结果表明:新理论在研究白噪声激励下船舶非线性横摇运动是非常有效的。

关键词： FPK方程白噪声联合概率密度函数稳定期望穿阈率非线性横摇运动

Wake Effects on A Hybrid Semi-Submersible Floating Wind Farm with Multiple Hub Heights

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China Ocean Engineering 2023年第1期37卷 101-114页

作者： XU Xiao-sen gu jia-yang LING Hong-jie YANG Pu-yi WANG Shuai-shuai XING Yi-han Oleg GAIDAI ZHANG Zhong-yu Marine Equipment and Technology Institute Jiangsu University of Science and TechnologyZhenjiang 212100China Department of Mechanical and Civil Engineering Florida Institute of TechnologyMelbourne 32901United States Department of Marine Technology Norwegian University of Science and TechnologyTrondheim 7491Norway Department of Mechanical and Structural Engineering and Materials Science University of StavangerStavanger 4021Norway College of Engineering Science and Technology Shanghai Ocean EngineeringShanghai 201306China

Wind farms generally consist of a single turbine installed with the same hub height. As the scale of turbines increases,wake interference between turbines becomes increasingly significant, especially for floating wind turbines(FWT).Some researchers find that wind farms with multiple hub heights could increase the annual energy production(AEP),while previous studies also indicate that wake meandering could increase fatigue loading. This study investigates the wake interaction within a hybrid floating wind farm with multiple hub heights. In this study, *** is employed to simulate a hybrid wind farm which consists of four semi-submersible FWTs(5MW and 15MW) with two different hub heights. Three typical wind speeds(below-rated, rated, and over-rated) are considered in this paper to investigate the wake meandering effects on the dynamics of two FWTs. Damage equivalent loads(DEL) of the turbine critical components are computed and analyzed for several arrangements determined by the different spacing of the four turbines. The result shows that the dynamic wake meandering significantly affects downstream turbines’ global loadings and load effects. Differences in DEL show that blade-root flapwise bending moments and mooring fairlead tensions are sensitive to the spacing of the turbines.

关键词： hybrid floating wind farm wake meandering multiple hub heights floating wind turbine FAST.Farm fatigue

一种新的路径积分法在船舶横摇概率计算中的应用(英文)

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船舶力学 2006年第6期10卷 43-52页

作者：谷家扬江苏科技大学船舶与海洋工程学院江苏镇江212003

基于Gauss-Legendre积分规则提出了一种新的路径积分法来计算随机横浪中船舶非线性横摇运动的概率密度分布,新的路径积分法能够得出精确的瞬态概率密度分布,包括系统响应尾部区域的概率分布,其对系统的可靠性分析是十分重要的。船舶随... 详细信息

基于Gauss-Legendre积分规则提出了一种新的路径积分法来计算随机横浪中船舶非线性横摇运动的概率密度分布,新的路径积分法能够得出精确的瞬态概率密度分布,包括系统响应尾部区域的概率分布,其对系统的可靠性分析是十分重要的。船舶随机横摇运动微分方程考虑到阻尼力与恢复力的非线性。数值模拟了联合概率密度函数随时间的演变,分析了外部激励强度对船舶稳态概率密度分布的影响。数值模拟的结果表明新的路径积分法对研究船舶非线性横摇运动概率密度分布是十分有效的。

关键词：路径积分法 FPK方程瞬态联合概率密度非线性横摇随机激励

Compact All-Fiber 102W Picosecond MOPA Laser with a Narrow Spectral Linewidth

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Chinese Physics Letters 2011年第11期28卷 121-123页

作者： WU Wen-Di REN Ting-Qi ZHOU Jun DU Song-Tao gu Xi-jia LOU Qi-Hong College of Physics and Engineering Qufu Normal UniversityQufu 273165 Shanghai Key Laboratory of All Solid-State Laser and Applied Techniques Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800 Department of Electrical and Computer Engineering Ryerson UniversityTorontoCanada

We report an all-fiber-based master oscillator power amplifier picosecond ytterbium-doped fiber laser with an average power of 102W and a spectral line width of 0.1 *** seed source is a compact single mode passively mode-locked fiber laser with an average power of 2.48 ***,the laser maximum average output power of 102W picosecond pulses is realized by a direct all-fiber amplifier structure in one *** experiment enables the optical-to-optical conversion efficiency to reach 61.4%,with the central wavelength of 1063.7nm.A significant feature of this experiment is the spectral line width of 0.1 *** spectrum has no broadening or nonlinear effects when the pump is strengthened.

关键词： amplifier fiber pump

Combining surgery with 125I brachytherapy for recurrent mediastinal dedifferentiated liposarcoma: A case report and review of literature

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World Journal of Clinical Cases 2020年第5期8卷 939-945页

作者： Hui-guo Chen Kai Zhang Wei-Bin Wu Yong-Hui Wu jian Zhang Li-jia gu Xiao-Jun Li Department of Cardiothoracic Surgery the Third Affiliated Hospital of Sun Yat-sen University

BACKGROUND Dedifferentiated liposarcoma in the mediastinum is an extremely rare malignant neoplasm.A few previous case reports indicate that surgical resection is the major treatment,but frequent recurrence occurs *** to its rarity,its clinical characteristics,optimal treatment and clinical outcomes remain ***,we report a case of multifocal recurrent dedifferentiated liposarcoma in the posterior mediastinum treated by combining surgery with 125I brachytherapy,and summarize its clinical features,treatment and *** SUMMARY A 75-year-old man was admitted to our hospital with a history of gradual dysphagia for one year and aggravated dysphagia for 3 ***-enhanced computed tomography(CT)revealed several large cystic-solid masses with lipomatous density,and calcification in the posterior-inferior *** patient received a wide excision by video-assisted thoracoscopic *** analysis confirmed the tumors were dedifferentiated *** tumor locally relapsed 24 mo later,and another operation was performed by video-assisted thoracoscopic *** months after the second surgery,the tumor recurred again,and the patient received CT-guided radioactive seeds 125I *** 8 mo,follow-up chest CT showed an enlarged ***,his condition exacerbated with severe dysphagia and dyspnea,and he died of respiratory failure in July *** We reviewed the literature,and suggest that surgical resection provides beneficial effects for dedifferentiated liposarcoma in the mediastinum,even in cases with local recurrence.125I brachytherapy may be beneficial for recurrent unresectable patients.

关键词： Dedifferentiated liposarcoma Mediastinal neoplasms Recurrence Reoperation 125I brachytherapy Case report

Characteristics of LDPE and Oriented Montmorillonite Nanocomposites Produced by Electric Field-inducement

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高电压技术 2013年第8期39卷 1947-1951页

作者： BAI Ge LIAO Ruijin YANG Lijun YUAN Yuan gu jia State Key Laboratory of Transmission & Distribution Equipments and Power System Safety and New Technology Chongqing University Chongqing 400030 China

In order to make montmorillonite (MMT) nanosheets disperse in low-density polyethylene (LDPE) with highly homogeneous orientation, alternating voltage is applied to molten LDPE with MMT nanosheets. The effect of electric field on the dispersion of MMT in the solidified LDPE is studied. X-ray diffraction (XRD) and scanning electron microscopy (SEM) analyses suggest that the MMT nano- sheets are aligned with high anisotropy to the electric field direction, which is perpendicular to the LDPE film plane. Differential scanning calorimetry (DSC) results reveal that the crystallization degree of the oriented LDPE/MMT composite increases. Moreover, through a broadband dielectric spectroscopy analyzer, it is found that MMT manifests a significantly influence in the dielectric property of the oriented composite: the dielectric constant and loss tangent of the composite both become larger. Analysis shows that the electric field-induced torque caused by the polarization of MMT flakes is the main force inducing the orientation of the MMT flakes.

关键词：纳米复合材料 LDPE薄膜电场方向介电特性蒙脱土低密度聚乙烯扫描电子显微镜差示扫描量热法

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中国乳品工业的结构和运行特点(上)

中国乳业 2014年第1期 28-31页

作者：顾佳升中国奶业协会乳品工业委员会

中国乳品工业是在资源紧缺的环境里萌芽和发展的,不仅产品结构具有特殊性,产业结构也具有特殊性。本文在回顾产业成型的历史过程的基础上,分析了中国乳品工业产品组合的单一性,以及若干运行特点,进一步指出了行业结构转型的必要性。

关键词：产业结构产业规划产品组合生产统计行业管理行业监督乳品工业

Numerical Simulations and Model Tests of the Mooring Characteristic of A Tension Leg Platform Under Random Waves

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China Ocean Engineering 2013年第5期27卷 563-578页

作者：谷家扬杨建民吕海宁 State Key Laboratory of Ocean Engineering Shanghai JiaoTong University School of Naval Architecture and Marine Engineering Jiangsu University of Scienceand Technology

Analyzing the dynamic response and calculating the tendon tension of the mooring system are necessary for the structural design of a tension leg platform （TLP）. The six-degree-of-freedom dynamic coupling responses and the mooring characteristics of TLP under random waves are studied by using a self-developed program. Results are verified by the 1：40 scaling factor model test conducted in the State Key Laboratory of Ocean Engineering at Shanghai jiaoTong University. The mean, range, and standard deviation of the numerical simulation and model test are compared. The influences of different sea states and wave approach angles on the dynamic response and tendon tension of the mooring system are investigated. The acceleration in the center and corner of the deck is forecasted.

关键词： TLP nonlinear stochastic waves model test coupled response

Metabonomic studies of pancreatic cancer response to radiotherapy in a mouse xenograft model using magnetic resonance spectroscopy and principal components analysis

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World Journal of Gastroenterology 2013年第26期19卷 4200-4208页

作者： Xin-Hong He Wen-Tao Li Ya-jia gu Bao-Feng Yang Hui-Wen Deng Yi-Hua Yu Wei-Jun Peng Department of Radiology Fudan University Shanghai Cancer Center Shanghai Key Laboratory of Functional Magnetic Resonance Imaging Physics Department East China Normal University

AIM: To investigate the metabolic profiles of xenograft pancreatic cancer before and after radiotherapy by high-resolution magic angle spinning proton magnetic resonance spectroscopy (HRMAS 1H NMR) combined with principal components analysis (PCA) and evaluate the radiotherapeutic effect. METHODS: The nude mouse xenograft model of human pancreatic cancer was established by injecting human pancreatic cancer cell SW1990 subcutaneously into the nude mice. When the tumors volume reached 800 mm3 , the mice received various radiation doses. Two weeks later, tumor tissue sections were prepared for running the NMR measurements. 1H NMR and PCA were used to determine the changes in the metabolic profiles of tumor tissues after radiotherapy. Metabolic profiles of normal pancreas, pancreatic tumor tissues, and radiationtreated pancreatic tumor tissues were compared. RESULTS: Compared with 1H NMR spectra of the normal nude mouse pancreas, the levels of choline, taurine, alanine, isoleucine, leucine, valine, lactate, and glutamic acid of the pancreatic cancer group were increased, whereas an opposite trend for phosphocholine, glycerophosphocholine, and betaine was observed. The ratio of phosphocholine to creatine, and glycerophosphocholine to creatine showed noticeable decrease in the pancreatic cancer group. After further evaluation of the tissue metabolic profile after treatment with three different radiation doses, no significant change in metabolites was observed in the 1H NMR spectra, while the inhibition of tumor growth was in proportion to the radiation doses. However, PCA results showed that the levels of choline and betaine were decreased with the increased radiation dose, and conversely, the level of acetic acid was dramatically increased. CONCLUSION: The combined methods were demonstrated to have the potential for allowing early diagnosis and assessment of pancreatic cancer response to radiotherapy.

关键词： High-resolution magic angle spinning proton magnetic resonance spectroscopy Principal components analysis Pancreatic cancer Radiotherapy