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蓄电池混合储能系统研究

上海船舶运输科学研究所学报 2024年第3期47卷 43-50页

作者：朱江南通中远海运船务工程有限公司江苏南通226006

锂离子电池系统成本高昂是阻碍其在电动设备中广泛使用的最大挑战之一。对某船采用的电池混合储能系统(Hybrid Energy Storage System,HESS)进行研究,分析电池混合对成本、系统效率和电池重量等3个关键指标的影响。该HESS的使用寿命设计... 详细信息

锂离子电池系统成本高昂是阻碍其在电动设备中广泛使用的最大挑战之一。对某船采用的电池混合储能系统(Hybrid Energy Storage System,HESS)进行研究,分析电池混合对成本、系统效率和电池重量等3个关键指标的影响。该HESS的使用寿命设计为10 a,采用镍钴锰酸锂和钛酸锂作为高能(High-Energy,HE)和高功率(High-Power,HP)电池单体。研究表明,与采用HP电池和HE电池的单一型电池储能系统相比,HESS的效率没有下降,成本能分别下降约28%和14%,总重量能减少30%以上。

关键词：电池系统成本混合储能系统海洋应用集装箱船

A Dataset of Global Ocean Surface Currents for 1999-2007 Derived from Argo Float Trajectories: A Comparison with Surface Drifter and TAO Measurements

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Atmospheric and Oceanic Science Letters 2009年第2期2卷 97-102页

作者： XIE Jiping zhu jiang ICCES Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China LAPC Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

A dataset of surface current vectors with error estimate from 1999 to 2007 is derived from the trajectories of the Array for Real-time Geostrophic Oceanography (Argo) drifting on surface over the global ocean. The error of the estimated surface currents is about 4.7 cm s-1 which is equivalent to the accuracy of the currents determined from the surface drifters. Geographically, the Argo-derived surface currents can fill many gaps left by the Global Drifter Program due to the greater number of floats, and can provide a complementary in situ observational system for monitoring global ocean surface currents. The surface currents from the Argo floats are compared with the surface drifter-derived currents and the Tropical Atmosphere Ocean program (TAO) measurements. The comparisons show good agreement for both the current amplitude and the direction of surface currents. Results indicate the feasibility of obtaining ocean surface currents from the Argo array and of combining the surface currents from Argo and the ocean surface drifters for in situ mapping of the global surface currents. The authors also make the dataset available to users of interest for many types of applications.

关键词： Argo浮标 DataSet 表面电流全球海洋测量浮法误差估计电流矢量

Relationship between real meridional volume transport and Sverdrup transport in the North Subtropical Pacific

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Chinese Science Bulletin 2006年第14期51卷 1757-1760页

作者： jiang Hua WANG Hui zhu jiang TAN Benkui Institute of Climate System Chinese Academy of Meteorological Sciences Beijing 100081 China Chinese Academy of Meteorological Sciences Beijing 100081 China Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Department of Atmospheric Science School of Physics Peking University Beijing 100871 China

The oceanic meridional volume trans-port (MVT) in the North Subtropical Pacific is calcu-lated directly from an observed velocity field (realMVT) and indirectly from wind stress based on Sver-drup balance, respectively. It is confirmed that theSverdrup MVT is a good approximation to the realMVT for the North Subtropical Pacific except in thewestern boundary region, where the difference isexpected because of frictional and nonlinear effects.The time evolution of the MVT derived from a revisedSverdrup balance, in which a time delay due to thepropagation of the first baroclinic Rossby wave isconsidered, is well correlated with that of the realMVT on decadal time scale, especially near thewestern boundary region. It is suggested that theSverdrup balance can be used to study not only themean climatology of the oceanic circulation, but alsothe time-dependent oceanic circulation of the NorthSubtropical Pacific when the Rossby wave propaga-tion is taken into account.

关键词：斯维尔德鲁普运输时延 MVT 亚热带太平洋

Two new least-squares mixed finite element procedures for convection-dominated Sobolev equations

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Applied Mathematics(A Journal of Chinese Universities) 2011年第4期26卷 401-411页

作者： ZHANG Jian-song YANG Dan-ping zhu jiang Department of Computational and Applied Mathematics China Universityof Petroleum Tsingdao 266555 China. Department of Mathematics East China Normal University Shanghai 200062 China. Laborat6rio Nacional de Computcao Cientifica 25651-075 Petropolis R J Brazil.

Two new convection-dominated are derived under the approximate solutions least-squares mixed finite element procedures are formulated for solving Sobolev equations. Optimal H（div;Ω）×H1（Ω） norms error estimates standard mixed finite spaces. Moreover, these two schemes provide the with first-order and second-order accuracy in time increment, respectively.

关键词： Least-square mixed finite element convection-dominated Sobolev equation convergence analysis.

Reputation-based secure spectrum situation fusion in distributed cognitive radio networks

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The Journal of China Universities of Posts and Telecommunications 2015年第3期22卷 110-117页

作者： Li Fangwei Liu Fan zhu jiang Nie Yifang School of Communication and Information Engineering Chongqing University of Posts and Telecommunications

In distributed cognitive radio （CR） network, the cooperative spectrum situation sensing based on consensus scheme may be disrupted by spectrum sensing data falsification （SSDF） attacks. In this paper, a secure spectrum situation fusion scheme based on reputation is proposed to counter attacks. The neighboring nodes of secondary users （SUs） get the corresponding dynamic trust value according to their behavior, which restrict the impact of the malicious behavior on the premise to ensure information interaction of normal nodes. Theoretical analysis and simulation results show that the consensus fusion scheme based on reputation has better performance than the existing algorithm which eliminates the neighboring node with the biggest deviation value from mean value. It demonstrates that the proposed scheme not only achieves better convergence properties but also has higher detection probability than the existing scheme in the process of spectrum situation fusion.

关键词： cognitive radio spectrum situation fusion secure consensus spectrum sensing data falsification （SSDF） attack

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固态发酵对麦麸物理化学性质的影响研究

粮油食品科技 2024年第1期32卷 44-49页

作者：张笃芹慎珠江谭斌国家粮食与物资储备局科学研究院粮油加工研究所北京100037 中原食品实验室河南漯河462300

利用酿酒酵母和植物乳杆菌对麦麸进行了单菌和混菌固态发酵,通过分析测定固态发酵对麦麸物理化学性质、膳食纤维含量和组成的影响及各指标之间的相关性,初步阐述了固态发酵改善麦麸营养及加工品质的可能原因,有利于拓展发酵麦麸在全谷... 详细信息

利用酿酒酵母和植物乳杆菌对麦麸进行了单菌和混菌固态发酵,通过分析测定固态发酵对麦麸物理化学性质、膳食纤维含量和组成的影响及各指标之间的相关性,初步阐述了固态发酵改善麦麸营养及加工品质的可能原因,有利于拓展发酵麦麸在全谷物食品加工产业的应用。结果显示,固态发酵麦麸的可溶性膳食纤维(SDF)和阿拉伯木聚糖含量分别提高了40.6%和15.2%;酿酒酵母和植物乳杆菌混菌固态发酵麦麸的持水能力和持油能力最高;固态发酵使麦麸的峰值变性温度(TP)、焓变和结晶度分别由195.35℃、3869.50J/g和15.86%显著降低至178.30℃、3276.67J/g和15.24%(P<0.05)。麦麸中SDF含量与结晶度、TP显著负相关,相关系数分别为–0.959 47、–0.950 7。固态发酵使麦麸由结构完整和紧凑转变为疏松和分散,植物细胞的清晰度和均匀性也明显下降。综上所述,固态发酵在微生物的代谢作用下降低了麦麸内部组织结构的致密性,不仅有利于功能活性成分的释放,还可显著改善其加工品质。

关键词：麦麸固态发酵膳食纤维物理化学性质相关性分析

The error source analysis of oil spill transport modeling: a case study

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Acta Oceanologica Sinica 2013年第10期32卷 41-47页

作者： LI Yan zhu jiang WANG Hui KUANG Xiaodi University of the Chinese Academy of Sciences Key Laboratory of Research on Marine Hazards Forecasting National Marine Environmental Forecasting CenterState Oceanic Administration Institute of Atmospheric Physics Chinese Academy of Sciences Marine Environmental Forecasting Division National Marine Environmental Forecasting CenterState Oceanic Administration

Numerical modeling is an important tool to study and predict the transport of oil spills. However, the accu- racy of numerical models is not always good enough to provide reliable information for oil spill transport. It is necessary to analyze and identify major error sources for the models. A case study was conducted to analyze error sources of a three-dimensional oil spill model that was used operationally for oil spill forecast- ing in the National Marine Environmental Forecasting Center （NMEFC）, the State Oceanic Administration, China. On June 4, 2011, oil from sea bed spilled into seawater in Penglai 19-3 region, the largest offshore oil field of China, and polluted an area of thousands of square kilometers in the Bohai Sea. Satellite remote sensing images were collected to locate oil slicks. By performing a series of model sensitivity experiments with different wind and current forcings and comparing the model results with the satellite images, it was identified that the major errors of the long-term simulation for oil spill transport were from the wind fields, and the wind-induced surface currents. An inverse model was developed to estimate the temporal variabil- ity of emission intensity at the oil spill source, which revealed the importance of the accuracy in oil spill source emission time function.

关键词： error source oil spill lagrangian random walk

基于外腔面发射激光器腔内三倍频的可调谐紫外激光器

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物理学报 2024年第8期73卷 115-122页

作者：成佳伍亚东晏日彭雪芳朱仁江王涛蒋丽丹佟存柱宋晏蓉张鹏重庆师范大学物理与电子工程学院重庆401331 中国科学院长春光学精密机械与物理研究所长春130033 北京工业大学理学部北京100124 重庆师范大学重庆国家应用数学中心重庆401331

紫外激光器具有频率高、波长短、单光子能量大以及空间分辨率高等特点,在精细加工、生命科学、光谱学等许多方面应用前景广阔.本文报道了一种基于外腔面发射激光器腔内三倍频的可调谐紫外激光器.该激光器采用了W型谐振腔,并插入双折射... 详细信息

紫外激光器具有频率高、波长短、单光子能量大以及空间分辨率高等特点,在精细加工、生命科学、光谱学等许多方面应用前景广阔.本文报道了一种基于外腔面发射激光器腔内三倍频的可调谐紫外激光器.该激光器采用了W型谐振腔,并插入双折射滤波片作为偏振和波长调谐元件,通过Ⅰ类相位匹配的LBO晶体对980 nm基频光进行倍频产生490 nm蓝光,再通过Ⅰ类相位匹配的BBO晶体对9.80 nm基频光和490 nm倍频光进行和频获得327 nm紫外输出.当LBO和BBO晶体的长度都为5 mm时,在环境温度为15℃,泵浦功率为47 W的条件下,实验输出的327 nm紫外激光功率达到538 mW.选择厚度为2 mm的双折射滤波片作为调谐元件,可获得的紫外激光器输出波长的连续调谐范围为8.6 nm.该紫外激光器同时显示了良好的光束质量和较好的功率稳定性.

关键词：可调谐外腔面发射激光器非线性频率变换三倍频

A Multivariate Empirical Orthogonal Function-Based Scheme for the Balanced Initial Ensemble Generation of an Ensemble Kalman Filter

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Atmospheric and Oceanic Science Letters 2010年第3期3卷 165-169页

作者： Zheng Fei zhu jiang International Center for Climate and Environment Science (ICCES) Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry (LAPC) Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

The initial ensemble perturbations for an ensemble data assimilation system are expected to reasonably sample model uncertainty at the time of analysis to further reduce analysis uncertainty. Therefore, the careful choice of an initial ensemble perturbation method that dynamically cycles ensemble perturbations is required for the optimal performance of the system. Based on the multivariate empirical orthogonal function (MEOF) method, a new ensemble initialization scheme is developed to generate balanced initial perturbations for the ensemble Kalman filter (EnKF) data assimilation, with a reasonable consideration of the physical relationships between different model variables. The scheme is applied in assimilation experiments with a global spectral atmospheric model and with real observations. The proposed perturbation method is compared to the commonly used method of spatially-correlated random perturbations. The comparisons show that the model uncertainties prior to the first analysis time, which are forecasted from the balanced ensemble initial fields, maintain a much more reasonable spread and a more accurate forecast error covariance than those from the randomly perturbed initial fields. The analysis results are further improved by the balanced ensemble initialization scheme due to more accurate background information. Also, a 20-day continuous assimilation experiment shows that the ensemble spreads for each model variable are still retained in reasonable ranges without considering additional perturbations or inflations during the assimilation cycles, while the ensemble spreads from the randomly perturbed initialization scheme decrease and collapse rapidly.

关键词： ensemble Kalman filter initial ensemble generation multivariate empirical orthogonal function