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基于树木生长形态的仿生计算算法 被引量:1
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作者 方旺盛 刘展 林慧英 《科技广场》 2015年第1期45-51,共7页
对树木生长过程和形态结构进行描述与抽象,用动态生长的生长树进行模拟,提出一种新的仿生算法:生长树算法。树木在生长过程中,趋光性促使枝叶寻求占据相对更有利的空间位置,朝向能获取更多光照的位置生长,此过程体现寻优原则。借用遗传... 对树木生长过程和形态结构进行描述与抽象,用动态生长的生长树进行模拟,提出一种新的仿生算法:生长树算法。树木在生长过程中,趋光性促使枝叶寻求占据相对更有利的空间位置,朝向能获取更多光照的位置生长,此过程体现寻优原则。借用遗传算法和蚁群算法的种群、个体评估等概念,借鉴信息素浓度机制,提出"光素浓度"衡量光照对生长树的叶枝节点的作用,叶枝节点个体不断探寻周围环境的光素浓度与外部环境进行信息交流,同时个体之间存在生长竞争关系,算法不断对个体进行评价、选择、生长,逐步个体的编码从而求得问题目标解。将算法应用于几个典型函数寻优,实验结果经与标准遗传算法进行对比,生长树算法具有迭代层数少、寻优速度快的优势。 展开更多
关键词 叶枝节点 光素浓度 生长树算法 植物生长 仿生算法 遗传算法
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The distribution and variation of elements in sediments off the Huanghe (Yellow) River mouth 被引量:3
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作者 乔淑卿 石学法 +4 位作者 高晶晶 刘焱光 杨刚 朱爱美 王昆山 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2013年第4期876-885,共10页
Surface sediment samples collected off the Huanghe (Yellow) River mouth during the period 2007-2009 were analyzed for major and trace element concentrations. Concentrations of 16 elements were measured using X-ray f... Surface sediment samples collected off the Huanghe (Yellow) River mouth during the period 2007-2009 were analyzed for major and trace element concentrations. Concentrations of 16 elements were measured using X-ray fluorescence spectrometry. Results demonstrate that sediment grain size is the dominant factor controlling the spatial variations of elemental concentrations. Correlation and cluster analyses allowed classification of the study area into four geochemical regions: Regions Ⅰ and Ⅲare characterized by high concentrations ofAl2O3, Fe2O3, MgO, Na2O, K2O, Cr, Cu, Mn, Ni, Pb, V, and Zn, and contain fine-grained sediments with mean grain size (Mz)〈22 μm; and; Regions Ⅱ and Ⅳcontain mostly coarse-grained sediments, and are characterized by high concentrations of SiO2, Na2O, and Zr. The sediment entering the sea from the Huanghe River and its tributaries is enriched in Ca. Thus, the Ca/Al ratio was used as an indicator of the proportion of sediments in the study area that originated from the Huanghe River. Ca/Al ratios decrease from Regions Ⅰ and Ⅱ(located in the nearshore zone of the Huanghe River delta) to Regions Ⅲand Ⅳ(distributed in the offshore zone of the northern Huanghe River delta, southern and southeastern Laizhou Bay area). 展开更多
关键词 Huanghe (Yellow) River Bohai Sea major and trace elements grain size heavy metals
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Comparison of inversion of Chlorophyll concentration in the Bohai Bay based on GOCI Data 被引量:1
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作者 ZHANG Xue ZHENG Xiao-shen 《Marine Science Bulletin》 CAS 2017年第2期62-74,共13页
Bohai bay has poor water circulation capacity and low self-purification capacity,and a large number of land-sourced pollutants are accepted every year.The estimation of chlorophyll concentration based on remote sensin... Bohai bay has poor water circulation capacity and low self-purification capacity,and a large number of land-sourced pollutants are accepted every year.The estimation of chlorophyll concentration based on remote sensing plays an important role in the study of marine red tide and the monitoring of water quality in the Bohai Bay.So it is necessary to select the best algorithm by comparing the performance of each algorithm.Choosing the best algorithm is helpful to improve the precision of chlorophyll concentration.Based on the in-situ measurement data of the Bohai Bay and the GOCI remote sensing reflectance data,the retrieval models of chlorophyll concentration were established in this paper by using the methods of fluorescence line height(FLH),OC3,blue-green band ratio and NIR-red band ratio.The above algorithms were evaluated by comparing the simulation results and the verification results.The results showed that there are obvious differences in the accuracy of different retrieval methods.The fitting and retrieval effect of FLH is the best and NIR-red band ratio is the worst,and the OC3is similar to the blue-green band ratio method. 展开更多
关键词 chlorophyll concentration GOCI fluorescence line height method Bohai Bay
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Photosynthetic Excitation Pressure Causes Violaxanthin De-epoxidation in Aging Cabbage (Brassica Oleracea L.) Leaves 被引量:1
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作者 Amarendra Narayan Misra Dariusz Latowski Kazimierz Strzalka 《Journal of Life Sciences》 2011年第3期182-191,共10页
The purpose of the present studies was analysis of the age induced changes in photochemical efficiency and xanthophyils cycle pigments of the primary cabbage (Brassica oleracea L. cv. Capitata f. alba) leaves. Photo... The purpose of the present studies was analysis of the age induced changes in photochemical efficiency and xanthophyils cycle pigments of the primary cabbage (Brassica oleracea L. cv. Capitata f. alba) leaves. Photochemical efficiency of photosystem Ⅱ (PS Ⅱ) was studied by a pulse amplitude modulated chlorophyll fluorescence apparatus, chlorophyll concentration was analysis spectrophotometrically and xanthophyll cycle pigments were estimated by high-pressure liquid chromatography (HPLC). Leaf senescence was accompanied with a decrease both in chlorophylls concentration, the photochemical efficiency and rate constant for PS Ⅱ photochemistry whereas non-photochemical parameters increased. Excitation pressure (1-qP) which is a measure of relative lumen acidification increased by 1.2x in aging leaves. The maximum quantum yield of PS Ⅱ showed no significant change. The level of de-epoxidised xanthophylls increased but the concentration of mono- and di-epoxy xanthophylls decreased in aging leaves. A linear relationship between the excitation pressure and the depoxidation state of the xanthophyll cycle pigments and lutein, during the onset of senescence suggests that excitation pressure can be used as a sensor for monitoring the onset of senescence as well for the de-epoxidation state of the xanthophylls responsible for non-photochemical quenching in stressed leaves. 展开更多
关键词 Cabbage (Brassica oleracea L.) violaxanthin cycle excitation pressure senescence photosynthetic parameters.
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Field Experiments of Multi-Channel Oceanographic Fluorescence Lidar for Oil Spill and Chlorophyll-a Detection 被引量:5
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作者 LI Xiaolong ZHAO Chaofang +1 位作者 MA Youjun LIU Zhishen 《Journal of Ocean University of China》 SCIE CAS 2014年第4期597-603,共7页
A Multi-channel Oceanographic Fluorescence Lidar(MOFL), with a UV excitation at 355 nm and multiple receiving channels at typical wavelengths of fluorescence from oil spills and chlorophyll-a(Chl-a), has been develope... A Multi-channel Oceanographic Fluorescence Lidar(MOFL), with a UV excitation at 355 nm and multiple receiving channels at typical wavelengths of fluorescence from oil spills and chlorophyll-a(Chl-a), has been developed using the Laser- induced Fluorescence(LIF) technique. The sketch of the MOFL system equipped with a compact multi-channel photomultiplier tube(MPMT) is introduced in the paper. The methods of differentiating the oil fluorescence from the background water fluorescence and evaluating the Chl-a concentration are described. Two field experiments were carried out to investigate the field performance of the system, i.e., an experiment in coastal areas for oil pollution detection and an experiment over the Yellow Sea for Chl-a monitoring. In the coastal experiment, several oil samples and other fluorescence substances were used to analyze the fluorescence spectral characteristics for oil identification, and to estimate the thickness of oil films at the water surface. The experiment shows that both the spectral shape of fluorescence induced from surface water and the intensity ratio of two channels(I495/I405) are essential to determine oil-spill occurrence. In the airborne experiment, MOFL was applied to measure relative Chl-a concentrations in the upper layer of the ocean. A comparison of relative Chl-a concentration measurements by MOFL and the Moderate Resolution Imaging Spectroradiometer(MODIS) indicates that the two datasets are in good agreement. The results show that the MOFL system is capable of monitoring oil spills and Chl-a in the upper layer of ocean water. 展开更多
关键词 oceanographic lidar oil spill marine environment fluorescence spectrum Raman scattering
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STUDY ON DETERMINATION OF TRACE Cu(Ⅱ) BY DDCT CHELATING RESIN PRECONCENTRATION AND THIN LAYER RESIN PHASE SPECTROPHOTOMETRY
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作者 LI Chunxiang YAN Yongsheng +1 位作者 SONG Huanyu WANG Yun 《Chinese Journal of Reactive Polymers》 2006年第2期161-166,共6页
A new method for determination of Cu(Ⅱ) by DDCT chelating resin preconcentration and thin layer resin phase spectrophotometry was developed. The method has a high sensitivity (ε455= 3.6×10^5L/mol·cm), ... A new method for determination of Cu(Ⅱ) by DDCT chelating resin preconcentration and thin layer resin phase spectrophotometry was developed. The method has a high sensitivity (ε455= 3.6×10^5L/mol·cm), which is 33 times higher than that of liquid phase spectrophotometry. It has a good selectivity (most coexisting ions could not influence determination) and an ideal precision [30μg Cu(Ⅱ), n=6, RSD= l.67%]. The content of Cu(Ⅱ) in water, high purity rare earth and its oxide was determined. The detection limit of Cu(Ⅱ) is 5.3μg/L , and the linear range is 0-7.2μg/ml. The result is satisfactory. 展开更多
关键词 Chelating resin PRECONCENTRATION Thin layer resin phase spectrophotometry TRACE Cu(Ⅱ)
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Underwater Optical Fiber Fluorescent System for Measuring Chlorophyll-a Concentration
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作者 WANG Li tian, YANG Ying, ZHENG Long jiang, WANG Yu tian (School of Electr. Eng., Yanshan University, Qinhuangdao 066004, CHN) 《Semiconductor Photonics and Technology》 CAS 2001年第4期225-229,共5页
Using optical fiber fluorescent technology,a new method for measuring alga concentration in water is presented. The system can realize on line measurement for alga concentration using He Ne laser as the light source. ... Using optical fiber fluorescent technology,a new method for measuring alga concentration in water is presented. The system can realize on line measurement for alga concentration using He Ne laser as the light source. It can also effectively detect weak signals. The system with a passive sensor head has such advantages as simple structure, high sensitivity and high accuracy. It has been demonstrated that this system can be used to monitor water quality and can also be used to survey some matter. 展开更多
关键词 Optical fiber fluorescence Chlorophyll a Detection of weak signal
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Geochemical Assessment of Heavy Metals in Surface Sediments: A Case Study of the Tema Port, Ghana
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作者 Elvis Nyarko Albert Fletcher Samuel Addo Bennet Atsu Kwame Foli Edem Mahu 《Journal of Shipping and Ocean Engineering》 2014年第3期79-92,共14页
Ten trace and heavy metals (Fe, Mn, Ni, Zn, Cu, Cd, As, Co, Cr and V) were analysed in sediments collected from nine stations at the Tema Port of Ghana, during the dry and wet seasons. Analysis of samples was done u... Ten trace and heavy metals (Fe, Mn, Ni, Zn, Cu, Cd, As, Co, Cr and V) were analysed in sediments collected from nine stations at the Tema Port of Ghana, during the dry and wet seasons. Analysis of samples was done using INAA (instrumental neutron activation analysis) for Mn, V, Cu, As and Cd, and AAS (atomic absorption spectrophotometry) for Fe, Cr, Zn, Ni and Co. The concentrations of metals in sediments followed the orders Fe 〉 V〉 Mn 〉 Cd 〉 Ni 〉 Zn 〉 Cu 〉As, for the dry season and Fe 〉 V 〉 Ni 〉 Cu 〉 Zn 〉 Mn 〉 Cd 〉As, for the wet season. Concentrations of Co and Cr were below detection limit, whiles Cu, Cd and Ni were found to be above the TELs (threshold effect levels) of NOAA's (National Oceanic and Atmospheric Administration's) SQuiRTs (screening quick reference tables) at most sites. Estimated enrichment factors for individual metals showed very high contamination of the port's sediments, with Cd occurring at all sites, and Cu, As, V and Ni occurring at some sites for both dry and wet seasons. Although sediments from the Tema Port were highly enriched with Cd, Cu, Ni and V above natural background levels, the overall PLI (pollution load index) per sampling station considering background values of the analysed elements indicated that metal pollution in the port's sediment is below 1, indicating relatively unpolluted sediment. 展开更多
关键词 Ghana INAA sediments Tema Port heavy metals
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Numerical Analysis of the Biogeochemical Parameters in the Bay of Bengal
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《Journal of Shipping and Ocean Engineering》 2016年第3期135-148,共14页
Oceanic nutrient cycling plays a key role in understanding how oceanic biogeochemical parameters respond in varying physical and anthropogenically controlled processes. OA (Objective Analysis) of monthly climatology... Oceanic nutrient cycling plays a key role in understanding how oceanic biogeochemical parameters respond in varying physical and anthropogenically controlled processes. OA (Objective Analysis) of monthly climatology of WOAI3 (World Ocean Atlas 13) nutrient data of 5 km resolution called Nutrient-Climo has been done in this paper for analyzing the nutrient-rich region in the BOB (Bay of Bengal) and the mechanisms of physical forces were examined using six years (2002-2007) global ocean monthly analysis datasets based on the SODA v2.0.4 (Simple Ocean Data Assimilation package). The upwelled zones established from the circulation pattern were well synchronized with the nitrate rich zones. The POC (particulate organic carbon) of 5 km resolution has been analyzed from MODIS (Moderate-resolution Imaging Spectroradiometer) data and Chl a (Chlorophyll a) concentration SeaWiFS (Sea-viewing Wide Field-of-view Sensor) data of 9 km resolution are used to predict the productive zones in the BOB. In this paper, we examined that Chl a concentration (above 0.5 mg/m3) is found during the post-monsoon followed by winter in the north-western, north-eastern coast and head BOB as the source of nutrients is also supplementary due to high input of litter and sediment associated nutrients that are released during estuarine transport. 展开更多
关键词 OA Nutrient-Climo Chl a POC MODIS ScaWiFS.
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Assessing the dynamics of chromophoric dissolved organic matter(CDOM) in the Yellow Sea and the East China Sea in autumn by EEMs-PARAFAC 被引量:8
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作者 YAN LiHong SU RongGuo +2 位作者 ZHANG ChuanSong SHI XiaoYong ZHU ChenJian 《Science China Chemistry》 SCIE EI CAS 2012年第12期2595-2609,共15页
In this study we have successfully characterized the fluorescent components of chromophoric dissolved organic matter(CDOM) in the Yellow Sea and the East China Sea in autumn using excitation-emission matrix fluorescen... In this study we have successfully characterized the fluorescent components of chromophoric dissolved organic matter(CDOM) in the Yellow Sea and the East China Sea in autumn using excitation-emission matrix fluorescence spectroscopy(EEMs) combined with parallel factor analysis(PARAFAC).PARAFAC aids the characterization of fluorescence CDOM by decomposing the fluorescence matrices into individual components.Four humic-like components(C1,C2,C3,and C4),one marine biological production component(C6),and two protein-like components(C5 and C7) were identified by PARAFAC.We researched the distributional patterns of fluorescence intensity,regression analyses between salinity,chlorophyll a concentration and fluorescence intensities of individual fluorophore,and regression analysis between salinity and fluorescence intensities percent of individual fluorophore.The results revealed that C2 and C4 showed conservative mixing behavior,while C1 and C3 possessed conservative mixing behavior in high salinity region and additional behavior in low and middle salinity region,which were considered to be derived from riverine and degradation of organic matter from resuspended and/or sinking particles and show non-conservative mixing behavior.In addition to riverine sources,the tryptophan-like C5 may receive widespread addition(likely from photo-degradation or biodegradation),while the most likely sources for the one marine humic-like C6 and tyrosine-like C7 were biological activity and microbial processing of plankton-derived CDOM,which were suggested to be of autochthonous origin and biologically labile.The application of EEM-PARAFAC modeling presents a unique opportunity to observe compositional changes,different mixing behavior and temporal variability in CDOM in the Yellow Sea and the East China Sea. 展开更多
关键词 chromophoric dissolved organic matter fluorescence excitation emission Matrix spectroscopy PARAFAC model the Yellow Sea the East China Sea Yangtze Estuary conservative mixing behavior non-conservative mixing behavior
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