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MEMS Inductor Consisting of Suspended Thick Crystalline Silicon Spiral with Copper Surface Coating
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作者 吴文刚 李轶 +4 位作者 黄风义 韩翔 张少勇 李志宏 郝一龙 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2006年第4期662-666,共5页
A novel MEMS inductor consisting of a planar single crystalline silicon spiral with a copper surface coating as the conductor is presented. Using a silicon-glass anodic bonding and deep etching formation-and-release p... A novel MEMS inductor consisting of a planar single crystalline silicon spiral with a copper surface coating as the conductor is presented. Using a silicon-glass anodic bonding and deep etching formation-and-release process,a 40μm-thick silicon spiral is formed, which is suspended on a glass substrate to eliminate substrate loss. The surfaces of the silicon spiral are coated with highly conformal copper by electroless plating to reduce the resis- tive loss in the conductor,with thin nickel film plated on the surface of the copper layer for final surface passivation. The fabricated inductor exhibits a self-resonance frequency higher than 15GHz,with a quality factor of about 40 and an inductance of over 5nil at 11.3GHz. Simulations based on a compact equivalent circuit model of the inductor and parameter extraction using a characteristic-function approach are carried out,and good agreement with measurements is obtained. 展开更多
关键词 MEMS inductor suspended spiral copper coating quality factor modeling and parameter extrac tion radio frequency
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Retrieval of chlorophyll a and suspended solid concen-trations by hyperspectral remote sensing in Taihu Lake,China 被引量:4
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作者 杨顶田 潘德炉 +3 位作者 张霄宇 张晓峰 何贤强 李淑菁 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2006年第4期428-434,共7页
Chlorophyll α(ch1-α) and suspended solid concentrations are two frequently used water quality parameters for monitoring a lake. Traditional measurement of ch1-α and suspended solids, requiring laborious laborator... Chlorophyll α(ch1-α) and suspended solid concentrations are two frequently used water quality parameters for monitoring a lake. Traditional measurement of ch1-α and suspended solids, requiring laborious laboratory work, which is often expensive and time consuming. Hyperspectral remote-sensing measurement provides a fast and easy tool for estimating water trophic status. In situ hyperspectral data on March 7-8, July 6-7, September 20 and December 7-8, 2004 and the corresponding water chemical data were used to regress the algorithm of water quality parameters. Results showed that the peak of water leaving radiance around 700 nm (R700) varied proportionally with ch1-α concentration, and moved to infrared when algal bloom occurred. The reflectance ratio of R702/R685 was well correlated with ch1-α when water surface in no algal bloom case and the correlation coefficient was better if absorption of phycocyanin was considered. The reflectance ratio R620/R531 was highly correlated to the concentration of suspended solids. The relationship between suspended solids and other band groups were also compared. Secchi disk depth could be calculated by non-linear correlation with suspended solids concentration. 展开更多
关键词 hyperspectral remote sensing chlorophyll a suspended solids Taihu Lake
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Impacts of internal waves on chlorophyll a distribution in the northern portion of the South China Sea 被引量:3
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作者 杨顶田 叶海彬 王桂芬 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2010年第5期1095-1101,共7页
Internal waves can bring nutrients to the upper level of water bodies and facilitate phytoplankton photosynthesis.Internal waves occur frequently in the northern portion of the South China Sea and inflict an important... Internal waves can bring nutrients to the upper level of water bodies and facilitate phytoplankton photosynthesis.Internal waves occur frequently in the northern portion of the South China Sea and inflict an important effect on chlorophyll a distribution.In this study,in-situ observation and satellite remote sensing data were used to study the effects of internal waves on chlorophyll a distribution.Based on the in-situ observations,lower chlorophyll a concentrations were present in the middle and bottom level in areas in which internal waves occur frequently,while the surface chlorophyll a distribution increased irregularly,and a small area with relatively higher chlorophyll a concentrations was observed in the area around the Dongsha Island.Satellite remote sensing showed that the chlorophyll a concentration increased in the area near Dongsha Island,where internal waves frequently occurred.The results of the increased chlorophyll a concentration in the surface water near Dongsha Island in the northern portion of the South China Sea indicated that internal waves could uplift phytoplankton and facilitate phytoplankton growth. 展开更多
关键词 internal waves chlorophyll a distribution northern South China Sea
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Short-and Long-Term Response of Phytoplankton to ENSO in Prydz Bay, Antarctica: Evidences from Field Measurements, Remote Sensing Data and Stratigraphic Biomarker Records 被引量:1
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作者 ZHAO Jun Hans-Ulrich Peter +5 位作者 ZHANG Haisheng HAN Zhengbing HU Chuanyu YU Peisong LU Bing Thomas S.Bianchi 《Journal of Ocean University of China》 SCIE CAS 2014年第3期437-444,共8页
The study provides one of the first lines of evidence showing linkages between Antarctic phytoplankton abundance and composition in response to ENSO, based on historical reconstruction of sediment biomarkers. In addit... The study provides one of the first lines of evidence showing linkages between Antarctic phytoplankton abundance and composition in response to ENSO, based on historical reconstruction of sediment biomarkers. In addition to sediment biomarkers, field measured and remote sensing data of phytoplankton abundance were also recorded from Prydz Bay, Eastern Antarctica. Com-munity structure of field measured phytoplankton showed significant El Ni?o/La Ni?a-related succession during 1990 to 2002. In general, the number of algae species decreased during El Ni?o and La Ni?a years compared to normal years. Austral summer monthly variation of remotely sensed chlorophyll-a (Chl-a), particulate organic carbon (POC), and sea surface temperature (SST) indicated that ENSO impacted the timing of phytoplankton blooms during 2007 to 2011. Phytoplankton blooms (indicated by Chl-a and POC) preceded the increases in SST during El Ni?o years, and lagged behind the SST increases during La Ni?a years. Stratigraphic record of marine sedimentary lipid (brassicasterol, dinosterol and alkenones) biomarkers inferred that the proportions of different algae (diatoms, dinoflagellates and haptophytes) changed significantly between El Ni?o and La Ni?a events. The relative proportion of diatoms increased, with that of dinoflagellates being decreased during El Ni?o years, while it was reversed during La Ni?a years. 展开更多
关键词 PHYTOPLANKTON ENSO remote sensing biomarker record Prydz Bay
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Lagrangian model of zooplankton dispersion:numerical schemes comparisons and parameter sensitivity tests 被引量:1
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作者 丘仲锋 Andrea M.DOGLIOLI +1 位作者 何宜军 Francois CARLOTTI 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2011年第2期438-445,共8页
This paper presents two comparisons or tests for a Lagrangian model of zooplankton dispersion:numerical schemes and time steps.Firstly,we compared three numerical schemes using idealized circulations.Results show that... This paper presents two comparisons or tests for a Lagrangian model of zooplankton dispersion:numerical schemes and time steps.Firstly,we compared three numerical schemes using idealized circulations.Results show that the precisions of the advanced Adams-Bashfold-Moulton(ABM) method and the Runge-Kutta(RK) method were in the same order and both were much higher than that of the Euler method.Furthermore,the advanced ABM method is more efficient than the RK method in computational memory requirements and time consumption.We therefore chose the advanced ABM method as the Lagrangian particle-tracking algorithm.Secondly,we performed a sensitivity test for time steps,using outputs of the hydrodynamic model,Symphonie.Results show that the time step choices depend on the fluid response time that is related to the spatial resolution of velocity fields.The method introduced by Oliveira et al.in 2002 is suitable for choosing time steps of Lagrangian particle-tracking models,at least when only considering advection. 展开更多
关键词 LAGRANGIAN numerical scheme time steps ZOOPLANKTON
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Remote Sensing Retrieval of Surface Suspended Sediment Concentration in the Yellow River Estuary 被引量:6
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作者 ZHAN Chao YU Junbao +4 位作者 WANG Qing LI Yunzhao ZHOU Di XING Qinghui CHU Xiaojing 《Chinese Geographical Science》 SCIE CSCD 2017年第6期934-947,共14页
Accurate assessment of surface suspended sediment concentration (SSSC) in estuary is essential to address several important issues: erosion, water pollution, human health risks, etc. In this study, an empirical cub... Accurate assessment of surface suspended sediment concentration (SSSC) in estuary is essential to address several important issues: erosion, water pollution, human health risks, etc. In this study, an empirical cubic retrieval model was developed for the retrieval of SSSC from Yellow River Estuary. Based on sediments and seawater collected from the Yellow River and southeastern Laizhou Bay, SSSC conditions were reproduced in the laboratory at increasing concentrations within a range common to field observations. Continu- ous spectrum measurements of the various SSSCs ranging from 1 to 5700 mg/1 were carried out using an AvaField-3 spectrometer. The results indicated the good correlation between water SSSC and spectral reflectance (Rrs) was obtained in the spectral range of 726-900 nm. At SSSC greater than 2700 mg/L, the 740-900 nm spectral range was less susceptible to the effects of spectral reflectance saturation and more suitable for retrieval of high sediment concentrations. The best correlations were obtained for the reflectance ratio of 820 nm to 490 nm. Informed by the correlation between Rrs and SSSC, a retrieval model was developed (R2 = 0.992). The novel cubic model, which used the ratio of a near-infrared (NIR) band (740-900 nm) to a visible band (400-600 nm) as factors, provided robust quantifica- tion of high SSSC water samples. Two high SSSC centers, with an order of 103 mg/1, were found in the inversion results around the abandoned Diaokou River mouth, the present Yellow River mouth to the abandoned Qingshuigou River mouth. There was little sedi- ment exchange between the two high SSSC centers due to the directions of the residual currents and vertical mixing. 展开更多
关键词 surface suspended sediment concentration (SSSC) water spectral reflectance cubic model quantitative remote sensinginversion Yellow River Estuary
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Study on the influence of the subsurface buoy's vibration on the vector sensor due to ocean current
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作者 师俊杰 Sun Dajun Lv Yunfei Lan Hualin Mei Jidan 《High Technology Letters》 EI CAS 2014年第3期223-229,共7页
Subsurface buoy systems,especially equipped with the vector sensor,have more and more extensive applications in military and civilian regions.However,their acoustic performances are constrained by the vibration result... Subsurface buoy systems,especially equipped with the vector sensor,have more and more extensive applications in military and civilian regions.However,their acoustic performances are constrained by the vibration resulting from the unavoidable ocean current in some degree.The influence of such vibrations is quantitatively analyzed by means of modeling the simplified models of two deployment configurations involving the positive buoyant buoy and neutral buoy system.The corresponding formulas are deduced respectively for the deployment configuration buoy systems in the motion state firstly.Then the simulation software is developed and some numerical simulations are put up via the Runge-Kutta method.The simulation results and theoretical analysis indicate that the neutral buoy will be an excellent design protocol in engineering application in comparison with the positive buoyant buoy. 展开更多
关键词 subsurface buoy system vector sensor ocean current neutral buoy
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Optical closure of parameterized bio-optical relationships
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作者 贺双颜 FISCHER Jürgen +1 位作者 SCHAALE Michael 贺明霞 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2014年第2期480-489,共10页
An optical closure study on bio-optical relationships was carried out using radiative transfer model matrix operator method developed by Freie Universitat Berlin. As a case study, the optical closure of bio-optical re... An optical closure study on bio-optical relationships was carried out using radiative transfer model matrix operator method developed by Freie Universitat Berlin. As a case study, the optical closure of bio-optical relationships empirically parameterized with in situ data for the East China Sea was examined. Remote-sensing reflectance (Rrs) was computed from the inherent optical properties predicted by these biooptical relationships and compared with published in situ data. It was found that the simulated Rrs was overestimated for turbid water. To achieve optical closure, bio-optical relationships for absorption and scattering coefficients for suspended particulate matter were adjusted. Furthermore, the results show that the Fournier and Forand phase functions obtained from the adjusted relationships perform better than the Petzold phase function. Therefore, before bio-optical relationships are used for a local sea area, the optical closure should be examined. 展开更多
关键词 optical closure ocean color remote sensing bio-optical relationship
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Simplified Echo-State-Network Based Services Awareness for High-Speed Passive Optical Network 被引量:1
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作者 Huifeng Bai Dongshan Wang Yanbin Song 《China Communications》 SCIE CSCD 2017年第6期13-21,共9页
With the challenge from services diversity grows greatly,the service-oriented supporting ability is required to current high-speed passive optical network(PON) .Aimed to enhance the quality of service(Qo S) brought by... With the challenge from services diversity grows greatly,the service-oriented supporting ability is required to current high-speed passive optical network(PON) .Aimed to enhance the quality of service(Qo S) brought by diversified-services,this paper proposes an Simplified Echo State Network(SESN) Based Services Awareness scheme in High-Speed PON(Passive Optical Network) .In this proposed scheme,the ring topology is adopted in the reservoir of SESN to reduce the complexity of original Echo State Network,and system dynamics equation is introduced to keep the accuracy of SESN.According to the network architecture of 10G-EPON,a SESN Master is running in the OLT and a number of SESN Agents work in ONUs.The SESN Master plays the main function of service-awareness from the total view of various kinds services in 10G-EPON system,by fully SESN training.Then,the reservoir information of well-trained SESN in OLT will be broadcasted to all ONUs and those SESN Agents working in ONUs are allowed to conducts independent service-awareness function.Thus,resources allocation and transport policy are both determined just only in ONUs.Simulation results show that the proposed mechanism is able to better supporting ability for multiple services. 展开更多
关键词 passive optical network servicesawareness simplified echo state network reservoir computation
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谢芳作品
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《艺术界》 2002年第4期119-119,共1页
《镜子系列·对话》
关键词 不明飞行物 “镜像” 矛盾状态 自我怀疑 “他者” “自我” 浮感 异质 默察 作品
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Automatic extraction of floating ice at Antarctic continental margin from remotely sensed imagery using object-based segmentation 被引量:3
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作者 ZHAO ZiYing LIU Zhen GONG Peng 《Science China Earth Sciences》 SCIE EI CAS 2012年第4期622-632,共11页
Information of Antarctic iceberg and sea ice are valuable to Antarctic ice melting patterns studies which are helpful to understand climate conditions and general trends of our planet.This paper presents an automatic ... Information of Antarctic iceberg and sea ice are valuable to Antarctic ice melting patterns studies which are helpful to understand climate conditions and general trends of our planet.This paper presents an automatic floating ice extraction method based on image segmentation technology using region growing.It effectively solves the over-segmentation and under-segmentation problems by merging the gray,contour,location and other information of each ice-object.A pixel-based extraction method is proposed to extract the small ices within 5 pixels.LANDSAT TM data,Chinese environment disaster satellite HJ1B data,and MODIS 1B data used to detect Floating ice at Antarctic continental margin respectively.The results showed that the extraction accuracies of the three kinds of data were all higher than 81 percent,while the accuracies of both TM data and HJ1B data were higher than 90%.Object-based information extraction methods can not only obtain the total area and number of floating ice objects in the whole region,but also provide precise details of single objects,including area,perimeter,contour,average brightness. 展开更多
关键词 ANTARCTIC ice extraction image segmentation OBJECT-ORIENTED
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Suspended-core Fibers for Sensing Applications
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作者 Orlando FRAZAO Ricardo M. SILVA +2 位作者 Marta S. FERREIRA Jose L. SANTOS Antonio B. LOBO RIBEIRO 《Photonic Sensors》 SCIE EI CAS 2012年第2期118-126,共9页
A brief review on suspended-core fibers for sensing applications is presented. A historical overview over the previous ten years about this special designed microstructure optical fiber is described. This fiber presen... A brief review on suspended-core fibers for sensing applications is presented. A historical overview over the previous ten years about this special designed microstructure optical fiber is described. This fiber presents attractive optical properties for chemical/biological or gas measurement, but it can be further explored for alternative sensing solutions, namely, in-fiber interferometers based on the suspended-core or suspended-multi-core fiber, for physical parameter monitoring. 展开更多
关键词 Optical fiber sensor suspended core fiber INTERFEROMETRY
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PERSISTENCE, EXTINCTION AND STABILITY FOR NONLINEAR PLANKTON ALLELOPATHY MODEL WITH DELAYED NEGATIVE FEEDBACKS
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作者 YAN-PING LIU ZHI-XUE LUO 《International Journal of Biomathematics》 2012年第2期157-196,共40页
By the techniques of comparison argument and Lyapunov-like functionals, some criteria about persistence and extinction of the species are obtained. And then, with the help of constructing Lyapunov functionals and some... By the techniques of comparison argument and Lyapunov-like functionals, some criteria about persistence and extinction of the species are obtained. And then, with the help of constructing Lyapunov functionals and some new analysis method, sufficient conditions, provided with the form of average value of a function, to guarantee the stability of the system are derived. Finally, some examples together with their numerical simulations show the feasibility of these main results. Our conclusions are different from many existing forms for nonlinear competitive systems. 展开更多
关键词 PERSISTENCE EXTINCTION STABILITY TOXICANT Lyapunov functional delay.
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