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Advances in Atmospheric Sciences 2018年第11期35卷 1362-1371页

作者： Xia LIU Qiang WANG Mu MU CAS Key Laboratory of Ocean Circulation and Waves Institute of OceanologyChinese Academy of SciencesQingdao 266071China University of Chinese Academy of Sciences Beijing 100049China Institute of Atmospheric Sciences Fudan UniversityShanghai 200433China Pilot National Laboratory for Marine Science and Technology(Qingdao) Qingdao 266237China Center for Ocean Mega-Science Chinese Academy of SciencesQingdao 266071China

Based on the high-resolution Regional Ocean Modeling System(ROMS) and the conditional nonlinear optimal perturbation(CNOP) method, this study explored the effects of optimal initial errors on the prediction of the Kuroshio large meander(LM) path, and the growth mechanism of optimal initial errors was revealed. For each LM event, two types of initial error(denoted as CNOP1 and CNOP2) were obtained. Their large amplitudes were found located mainly in the upper 2500 m in the upstream region of the LM, i.e., southeast of Kyushu. Furthermore, we analyzed the patterns and nonlinear evolution of the two types of CNOP. We found CNOP1 tends to strengthen the LM path through southwestward extension. Conversely,CNOP2 has almost the opposite pattern to CNOP1, and it tends to weaken the LM path through northeastward contraction.The growth mechanism of optimal initial errors was clarified through eddy-energetics analysis. The results indicated that energy from the background field is transferred to the error field because of barotropic and baroclinic instabilities. Thus, it is inferred that both barotropic and baroclinic processes play important roles in the growth of CNOP-type optimal initial errors.

关键词： Kuroshio large meander predictability ROMS optimal initial error growth

Antenna-in-package system integrated with meander line antenna based on LTCC technology

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Frontiers of Information Technology & Electronic Engineering 2016年第1期17卷 67-73页

作者： Gang DONG Wei XIONG Zhao-yao WU Yin-tang YANG School of Microelectronics Xidian University

We present an antenna-in-package system integrated with a meander line antenna based on low temperature co-fired ceramic(LTCC) technology. The proposed system employs a meander line patch antenna, a packaging layer, and a laminated multi-chip module(MCM) for integration of integrated circuit(IC) bare chips.A microstrip feed line is used to reduce the interaction between patch and package. To decrease electromagnetic coupling, a via hole structure is designed and analyzed. The meander line antenna achieved a bandwidth of 220 MHz with the center frequency at 2.4 GHz, a maximum gain of 2.2 d B, and a radiation efficiency about 90% over its operational frequency. The whole system, with a small size of 20.2 mm×6.1 mm×2.6 mm, can be easily realized by a standard LTCC process. This antenna-in-package system integrated with a meander line antenna was fabricated and the experimental results agreed with simulations well.

关键词： AntennaAn-package (AiP), meander line antenna, Multi-chip module (MCM), Low temperature co-fired ceramic (LTCC)

Assessing the oscillation of channel geometry and meander migration cardinality of Bhagirathi River,West Bengal,India

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Journal of Geographical Sciences 2019年第4期29卷 613-634页

作者： Rakhohori Bag Ismail Mondal Jatisankar Bandyopadhyay Department of Remote Sensing&GIS Vidyasagar UniversityMidnapore-721102India Department of Marine Science University of CalcuttaKolkata-700019India

Lateral migration of the Bhagirathi River temporally creates unavoidable geomorphic hazards in West Bengal,India.The Bhagirathi River flows SW for-67.30 km betwee n the confluenee point of Ajay and Jalangi rivers in East Burdwan and Nadia districts of West Bengal.The course of Bhagirathi is notably migration prone and cultivates problematic changes along its course over time.In the study,we have looked into its migration tendency and unpredictability for past 238 years and then predicted the lateral shifting of river centerline using temporal satellite imageries-Landsat-5(TM)of 1987(8,December),1995(28,January),2005(7,January)and LISS-IV satellite imagery(2017,5 January);SOI Toposheet-1968-1969(79A/2,79A/3,79A/6 and 79A/7)and RennelPs map of 1779.Other highlights are the quest of fluvial features,oxbow lakes,mid-channel bars,channel migration rate,meander geometry,channel sinuosity in different parts of river course and the parts that experience intensive bank erosion.The entire river course has been subdivided into three segments;viz.reaches A,B and C.Investigation displays that degree of sinuosity decreases from its anterior course(1968)to the existing course(2017).Reach-specific outputs display that reach B is highly sinuous(SI value 1.94 in 2017)and SI increases temporarily,whereas for reaches A and C it decreases with time.The rate of migration is higher in reach B than that in reaches C and A.The study displays a notably decreasing trend of migration in comparison with its previous lateral migration and shows that the migration nature over time is intensively inconsistent and unpredictable except very few portions of the river course.The nature of deposition within the river channel shows an unstable behavior during the entire period of the study.meander geometry depicts a rapid change of river course innate to meander bends and shows a higher rate of migration by meander loop cut-off rather than lateral migration that reflects the inconsistency,erosion vulnerability and unpredictable nature of migration.Th

关键词： channel geometry sinuosity index braiding index meander geometry radius of curvature bend tightness index linear regression GIS

Development of River meander Model

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Journal of Geographical Research 2020年第1期3卷 14-17页

作者： Levent Yilmaz Nisantasi University 1453 NeocampusCivil Engineering DepartmentHydraulic Division80626MaslakIstanbulTurkey

In the studies of open-channel flow with suspended sediments,used a constant of Von Karmanκin a model for velocity profile.The augmentation parameters have been added by various researchers in more recent development of the boundary-layer theory of meander development.In this research new parameters will be included because of the existence of the turbulent flow region in meandering channels because of boundary-layer theory.

关键词： meander Flow Model Boundary layer Sediment

A　three－dimensional　ocean　general　circulation　model　for　mesoscale　eddies──Ⅰ　meander　simulation　and　linear　growth　rate

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Acta Oceanologica Sinica 1996年第1期15卷 31-53页

作者： Wang Jia and Moto Ikeda Rosenstiel School of Marine and Atmospheric Science University of Miami 4600 Rickenbacker Causeway Miami FL 33149 United States Graduate School of Environmental Earth Science Hokkaido University Sapporo 060 Japan

A three-dimensional, primitive-equation model, Blumberg's ECOMSI (Estuarine and Coastal Ocean Model with a Semi-Implicit scheme), is modified and applied to the simulation of the ocean mesoscale eddies and unstable baroclinic waves across a density front in a channel. The model uses a semi-implicit scheme to remove the most stringent Courant-Friedriechs-Levy (CFL) constraint. We have modified this model by introducing a predictor-corrector scheme to remove the inertial instability due to the Euler forward scheme in time used in the ECOMSI. Instead, the neutral amplification of the eigenvalue is obtained for the inertial oscillation. Thus,the new version of the model (called the predictorcorrector or P-C version) is able to simulate the unstable baroclinic waves and ocean mesoscale eddies in a very low viscosity environment. meanders of a current with some similarity to mesoscale features are well reproduced. The unstable baroclinic waves are examined for flat, positive (same sense as isopycnal tilt) and negative bottoms. The growth rates with flat, gentle, medium, and steep slopes and with different wavelength (wave number) channels are discussed. A gentle positive slope significantly suppresses the meandering wave growth rate which slightly shifts to a lower wave number coml. Rosenstiel School of Marine and Atmospheric Science, University of Miami, 4600 Rickenbacker Causeway, Miami, Florida 33149, USA. Email: Jia. wang rsmas. miami. edu. 2. Graduate School of Environmental Earth Science, Hokkaido University, Sapporo. Japan 060. Email: mikeda eoas. hokudai. ac. jp. pared to the flat bottom. A gentle 11egative slope, however, favors the 'va\'e growth with foe maximum shifting towardsthe higher wave number. When the negative slope becomes steeper, the growth rate slgnlflcantly reduces correspondingly.

关键词： mesoscale and meander

Fine Characterization Method for Interlayers in Complex meander River Sandstone Reservoir: A Case Study of Um7 Sand of C Oilfield in Bohai Bay Area

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International Journal of Geosciences 2019年第4期10卷 405-418页

作者： Jingmin Guo Wei Wang Jie Tan Qin Peng Dong Zhang Bohai Oilfield Research Institute of CNOOC Ltd. Tianjin Branch Tianjin China

Taking the Um7 meandering river complex sandstone reservoir of Bohai Bay C oilfield as an example, the interlayer type is defined according to the interlayer lithology and sedimentary genesis, and the identification mode of different types of interlayer is established, and the interlayer comparison of the whole area is carried out by using this mode. The results show that the interlayer can be further defined as the stable distributed interlayer and the randomly distributed interlayer according to the morphology of the interlayer. The distribution characteristics of the two types of interlayers are characterized by the well-to-well comparison method and the data analysis method, and the three-dimensional characterization is carried out. The results more closely reflect the spatial distribution of the interlayer, but also are closer to the underground real situation.

关键词： meander River Reservoir Interlayer Fine Characterization Horizontal Well Development

THE KUROSHIO meander/SOUTHERN OSCILLATION CONNECTION AND DROUGHT/FLOOD CYCLES IN THE CHANGJIANG RIVER

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Chinese Journal of Oceanology and Limnology 1995年第3期13卷 223-225页

作者： M.F.Gerstell Dept. of Planetary Sciences California Inst. of Technology USA

In response to a suggestion that the large meander of the Kuroshio is a good predictor of droughtsin the Changjiang River Valley, it is argued that more recent inceptions of the meander lend statisticalweigh to the belief that the large meander is itself a consequence of E1 Nino, and hence of the SouthernOscillation. The meander usually lags. Thus, if the meander reliably predicts droughts, the Tahiti componentof the Southern Oscillation will usually give six months’ extra warning.

关键词： Kuroshio meander Southern Oscillation connection drought/flood cycles Changjiang River

An Inductor Model for Analyzing the Performance of Printed meander Line Antennas in Smart Structures

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Journal of Electromagnetic Analysis and Applications 2014年第9期6卷 244-252页

作者： Shih-Ming Yang Chih-Hsin Huang Department of Aeronautics and Astronautics National Cheng Kung University Taiwan

meander line antenna has been considered desirable on flight vehicles to reduce drag and minimize aerodynamic disturbance;however, the antenna design and performance analysis have made mostly by trial-and-error. An inductor model by simulating the meander line sections as electrical inductors and the interconnecting radiation elements as a quasi-monopole antenna is developed to analyze the antenna performance. Experimental verifications of the printed meander line antennas embedded in composite laminated substrates show that the inductor model is effective to design and analyze. Of the 4 antennas tested, the discrepancy of resonant frequency in simulation and experiment is within 4.6%.

关键词： Inductor Model meander Line Antenna Smart Structure

THE meander OF KUROSHIO AND OSCILLATION IN A COUPLED OCEAN-ATMOSPHERE MODEL

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Acta meteorologica Sinica 1993年第3期7卷 338-346页

作者：刘秦玉徐启春王志联秦曾灏 Institute of Physical Oceanography Ocean University of QingdaoQingdao 266003 Shanghai Typhoon Research Center Shanghai 200030

A numerical experiment of an asynchronous coupled ocean-atmosphere model has been described in this paper.A two-layer global atmosphere general circulation model(OSU/IAP-AGCM)and a two-layer North Pacific Ocean general circulation model(NPOGCM)developed by Liu et al.(1992)are used in numerical experiment.The sea surface temperature anomaly(SSTA)corresponding to the meander of the Kuroshio is treated as the initial perturbation in the Pacific Ocean and the abnormal phenomena caused by the disturbance and the interaction between atmosphere and ocean,have been studied. The numerical experiment showed that the SST anomaly in the North Pacific could induce a new 30—60 day oscillation through the coupling between atmosphere and ocean and the interaction between the meander of the Kuroshio and atmosphere circulation is a positive feedback process.

关键词： air-sea coupling Kuroshio meander positive feedback

可转换债券中一类两期双边障碍巴黎期权的定价

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工程数学学报 2013年第3期30卷 361-369页

作者：李静程希骏张青中国科学技术大学统计与金融系合肥230026

本文研究可转换债券中嵌入的一类路径相关期权定价问题.尽管偏微分方程数值解方法可以获得这类期权的价格,然而数值算法的收敛速度很慢.为了获得快速而有效的定价方法,本文将可转换债券中的期权简化为两期双边障碍巴黎期权,并给出了这... 详细信息

本文研究可转换债券中嵌入的一类路径相关期权定价问题.尽管偏微分方程数值解方法可以获得这类期权的价格,然而数值算法的收敛速度很慢.为了获得快速而有效的定价方法,本文将可转换债券中的期权简化为两期双边障碍巴黎期权,并给出了这类两期双边障碍巴黎期权的风险中性价格关于到期时刻的Laplace变换.基于Euler数值逆算法求解了数值例子,数值结果表明该数值算法快速、稳定和有效.

关键词：可转换债券巴黎期权 Brownian meander Laplace变换 Euler算法