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一种改进扩展卡尔曼滤波算法的GPS多径抑制应用 被引量:4
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作者 李基武 符强 +2 位作者 孙希延 黄仁义 刘迎 《测绘科学》 CSCD 北大核心 2018年第6期167-172,共6页
在用EKF算法消除微弱GPS卫星信号中的噪声,并估计出多径幅度与码相位时延的码跟踪环中,由于各种误差的存在,从而降低了环路的跟踪性能。针对这一问题,该文在EKF算法的基础上提出了一种LSEKF算法,该LSEKF算法用最小二乘估计的原理对EKF... 在用EKF算法消除微弱GPS卫星信号中的噪声,并估计出多径幅度与码相位时延的码跟踪环中,由于各种误差的存在,从而降低了环路的跟踪性能。针对这一问题,该文在EKF算法的基础上提出了一种LSEKF算法,该LSEKF算法用最小二乘估计的原理对EKF算法所用的采样观测点进行修正,构造出一组无偏、均方误差和最小与空间分布确定的新型采样观测点,用来进行后续的滤波估计。仿真结果表明,相比EKF算法,LSEKF算法拥有更高的伪码跟踪精度,而且收敛速度更快,跟踪门限也更低。 展开更多
关键词 最小二乘估计 扩展卡尔曼滤波 多径 非线性滤波 跟踪门限
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Application of Projection Pursuit Evaluation Model Based on Real-Coded Accelerating Genetic Algorithm in Evaluating Wetland Soil Quality Variations in the Sanjiang Plain, China 被引量:34
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作者 fuqiang XIEYONGGANG WEIZIMIN 《Pedosphere》 SCIE CAS CSCD 2003年第3期249-256,共8页
A new technique of dimension reduction named projection pursuit is applied to model and evaluatewetland soil quality variations in the Sanjiang Plain, Helongjiang Province, China. By adopting the im-proved real-coded ... A new technique of dimension reduction named projection pursuit is applied to model and evaluatewetland soil quality variations in the Sanjiang Plain, Helongjiang Province, China. By adopting the im-proved real-coded accelerating genetic algorithm (RAGA), the projection direction is optimized and multi-dimensional indexes are converted into low-dimensional space. Classification of wetland soils and evaluationof wetland soil quality variations are realized by pursuing optimum projection direction and projection func-tion value. Therefore, by adopting this new method, any possible human interference can be avoided andsound results can be achieved in researching quality changes and classification of wetland soils. 展开更多
关键词 EVALUATION projection pursuit evaluation model real-coded acceleratinggenetic algorithm soil quality variations
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Phosphorus removal by the multipond system sediments receiving agricultural drainage in a headstream watershed 被引量:5
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作者 fuqiang YINCheng-qing MAYun 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2005年第3期404-408,共5页
Wetland systems in headstream watersheds are important to control the nonpoint source pollutant phosphorus. Experiments were conducted using intact sediment-water columns obtained from the multipond system in Liuchahe... Wetland systems in headstream watersheds are important to control the nonpoint source pollutant phosphorus. Experiments were conducted using intact sediment-water columns obtained from the multipond system in Liuchahe watershed of Chaohu Lake to determine its capacity to retain P. It was found that pond sediments had strong P retention ability. For the Hill pond, Village pond and Rice pond, their retention coefficient(A) were 288.3, 279.2 and 260.8 L/m2, respectively. The equilibrium P concentration(EPC_w) were 0.016, 0.028 and 0.018 mg/L, respectively. The Hill pond indicated the highest P retention ability. P retained in the pond sediments indicated high stable degree. P removal from the overlying water column into the pond sediments followed a first-order kinetic model. Under the experimental hydrological conditions, the retention time had a positive correlation with the P loading. The multipond system could provide enough retention time to retain P in drainage runoffs. At the P levels evaluated, the sediments of the multipond system are effective sinks to retain P from nonpoint source runoffs. 展开更多
关键词 PHOSPHORUS POND SEDIMENT WATERSHED nonpoint source
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Applying Fuzzy Matter-Element Model Based on AHP to Evaluating Bids of Water Saving Irrigation Project 被引量:4
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作者 PANFeng fuqiang +1 位作者 LIANGChuan LIUDong 《Journal of Northeast Agricultural University(English Edition)》 CAS 2003年第2期147-151,共5页
Owing to overcoming the characteristics that there are many economic and technical indexes which are fuzzy and incompatibility to each other in evaluating investment project,a new method is proposed.The method is base... Owing to overcoming the characteristics that there are many economic and technical indexes which are fuzzy and incompatibility to each other in evaluating investment project,a new method is proposed.The method is based on the matter-element analysis and combined with the concepts of fuzzy mathematics,which is called the method of fuzzy matter-element analysis.It constructs the compound fuzzy matter element with the investment projects,evaluation factors and their fuzzy value.Through establishing the best subjection degree (fuzzy value),complex fuzzy matter element of relational coefficient and weight aggregation of fuzzy matter-element model,the writer achieves on optimum order of the investment projects according to the calculated relational degree and finds the best project.In this paper,the calculation of weight adopts the analytical hierarchy process method(AHP).Through the actual example,it shows that the model is simple and its calculation is reliable.It is very significant for the engineering evaluated bid and investment decision. 展开更多
关键词 fuzzy matter element water saving irrigation evaluating bid AHP relational degree
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Applying GM(1,1) to Forecasting the Dynamic Variation of Groundwater in Chuang Ye Farm 被引量:4
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作者 FUHong fuqiang XUYa-qin 《Journal of Northeast Agricultural University(English Edition)》 CAS 2003年第1期92-96,共5页
The area of well rice in the sanjiang Plain is incresing recently.At the same time,the groundwater resource has been wasted.Thus,the resource of groundwater is shortening.More and more area appears the phenomenon of ... The area of well rice in the sanjiang Plain is incresing recently.At the same time,the groundwater resource has been wasted.Thus,the resource of groundwater is shortening.More and more area appears the phenomenon of “hanger pump” and “funnel”.According to these problems the paper adopts Chuang Ye farm as the research base,through handle the data of groundwater,applying GM(1,1) to forecasting the dynamic variation of groundwater.The writer hopes to provide some references about using groundwater resource of the area in the future for readers. 展开更多
关键词 GM(1 1) GROUNDWATER forecasting Chuang Ye Farm
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三种甲状腺影像报告和数据系统临床应用评估 被引量:5
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作者 傅强 熊颖 +3 位作者 闫妍 宋可馨 刘昊 张紫杰 《中国医学装备》 2020年第6期33-37,共5页
目的:评估3种甲状腺影像报告和数据系统(TIRADS)的临床应用价值。方法:选取168例患者的257个甲状腺结节,根据美国放射学会(ACR)TIRADS(ACR-TIRADS)、欧洲甲状腺协会(EU)TIRADS(EU-TIRADS)和韩国甲状腺协会(KTA)/韩国甲状腺放射科学会(KS... 目的:评估3种甲状腺影像报告和数据系统(TIRADS)的临床应用价值。方法:选取168例患者的257个甲状腺结节,根据美国放射学会(ACR)TIRADS(ACR-TIRADS)、欧洲甲状腺协会(EU)TIRADS(EU-TIRADS)和韩国甲状腺协会(KTA)/韩国甲状腺放射科学会(KSThR)TIRADS(KTA/KSThR-TIRADS)的归类,构建受试者工作特征(ROC)曲线,评价并比较其诊断价值,计算不同风险分层诊断灵敏度、特异度、阳性预测值、阴性预测值及准确率。结果:患者的257个甲状腺结节中有7个结节无法纳入EU-TIRADS进行分类。3种风险分层均随着分类级别提高,恶性率呈增高趋势。ACR-TIRADS、EU-TIRADS和KTA/KSThR-TIRADS的ROC曲线下面积(AUC)分别为0.874、0.855和0.880。ACR-TIRADS与KTA/KSThR-TIRADS间诊断灵敏度无显著性差异,但均大于EU-TIRADS,差异有统计学意义(x^2=0.083,x^2=0.083;P<0.05),EU-TIRADS特异度及准确率高于ACR-TIRADS和KTA/KSThR-TIRADS,差异有统计学意义(xACR-TIRADS2=0.030,x^2=0.010;xKTA/KSThR-TIRADS2=0.033,x^2=0.010,P<0.05)。结论:3种风险分层对于鉴别甲状腺结节良恶性均有临床应用价值,其中ACR-TIRADS和KTA/KSThR-TIRADS灵敏度高,EU-TIRADS特异度及准确率高。 展开更多
关键词 超声检查 甲状腺结节 甲状腺影像报告和数据系统(TIRADS) 超声恶性风险分层
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威灵仙化学成分及其药理活性最新研究进展 被引量:125
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作者 付强 王萍 +5 位作者 杜宇凤 程小玲 唐婷婷 邱露 袁海梅 史社坡 《成都大学学报(自然科学版)》 2018年第2期113-119,共7页
威灵仙为毛茛科植物威灵仙、棉团铁线莲、东北铁线莲的干燥根及根茎,为治疗类风湿性关节炎常用药.化学成分研究表明威灵仙主要含有皂苷、黄酮、木脂素、酚类、生物碱等成分;药理研究表明威灵仙具有抗炎、镇痛、抗肿瘤、抗菌等活性.通过... 威灵仙为毛茛科植物威灵仙、棉团铁线莲、东北铁线莲的干燥根及根茎,为治疗类风湿性关节炎常用药.化学成分研究表明威灵仙主要含有皂苷、黄酮、木脂素、酚类、生物碱等成分;药理研究表明威灵仙具有抗炎、镇痛、抗肿瘤、抗菌等活性.通过文献调研,对威灵仙在近十多年来的化学成分和药理作用相关研究进行归纳整理,拟为威灵仙进一步开发和临床合理用药提供线索和依据. 展开更多
关键词 威灵仙 化学成分 三萜皂苷 黄酮 药理活性
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Study on Entropy Weight Coefficient Method and Application for Water Quality Evaluation 被引量:1
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作者 MENBao-hui fuqiang ZHAOXie-jing 《Journal of Northeast Agricultural University(English Edition)》 CAS 2004年第1期66-68,共3页
In order to evaluate the quality of water environment, the conception of entropy is applied in information science, and the entropy weight model is built to evaluate comprehensively water quality. The indexes weights ... In order to evaluate the quality of water environment, the conception of entropy is applied in information science, and the entropy weight model is built to evaluate comprehensively water quality. The indexes weights of water quality are determined by value of entropy. This kind of method is applied on evaluating water quality in the new water to be built. The result shows that the water quality in it which supply water is between grade Ⅲ and Ⅳ, and the result is similar to that of gray related method. 展开更多
关键词 entropy weight coefficient method water quality gray related method
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Benefit Evaluation Model of Small Watershed Control Based on Projection Pursuit
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作者 JINJu-liang fuqiang 《Journal of Northeast Agricultural University(English Edition)》 CAS 2001年第2期128-132,共5页
A projection pursuit model is presented in this paper for comprehensive evaluation of benefits of small watershed control.By using the model,small watershed control samples with many benefit evaluation indexes can be ... A projection pursuit model is presented in this paper for comprehensive evaluation of benefits of small watershed control.By using the model,small watershed control samples with many benefit evaluation indexes can be synthesized projective values with one dimension.The samples can be naturally evaluated according to the projective values.The parameters of the model is optimized by using real coding beased accelerating genetic aglrothm,which overcomes the shortcomings of large computation amount and difficulty of computer programming in traditional projection prusuit methods,and provides a new way for wide applications of projection pursuit technique to different evaluation problems in agricultural systems engineering. 展开更多
关键词 small watershed control benefit evaluation projection pursuit genetic algorithm
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Applying PP Model Based on RAGA in Water Environment Quality Evaluation
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作者 PANFeng fuqiang +1 位作者 LIANGChuan LIUDong 《Journal of Northeast Agricultural University(English Edition)》 CAS 2004年第2期171-175,共5页
Projection Pursuit (PP) model is a technique of falling high dimension. Real coding based on Accelerating Genetic Algorithm (RAGA) is a method of optimum. Through combining the PP model and RAGA, the paper applies the... Projection Pursuit (PP) model is a technique of falling high dimension. Real coding based on Accelerating Genetic Algorithm (RAGA) is a method of optimum. Through combining the PP model and RAGA, the paper applies the model in the water environment quality evaluation. The writer takes the water quality evaluated indexes of each sample as projection direction and turns high dimension data into low dimension projection value. Thus, the writer achieves on evaluating the grade of water samples and its optimum order. Based on this, the writer overcomes the jamming of weights calculated on fuzzy synthesize judge and gray system valuation. The paper can provide a new thought for water environment quality evaluation and other falling high dimension and optimum issue. 展开更多
关键词 RAGA PP model water environment quality evaluation
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A Computer Method of Steady Non-Uniform Gradually Varied Flow in Open Channel & in River
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作者 fuqiang ChenYuguo 《Journal of Northeast Agricultural University(English Edition)》 CAS 1999年第1期56-61,共6页
Most of water flow in open channel or in river belongs to steady non-uniform flow. The surface profiles are caused by changes of channel section. It is very important to analyze its computation. According to the regu... Most of water flow in open channel or in river belongs to steady non-uniform flow. The surface profiles are caused by changes of channel section. It is very important to analyze its computation. According to the regularity of its surface change, the suitable sectional dimensions of open channel or flood control work can be designed. Commonly, computation of non-uniform flow adopts the traditional methods by hand or by graphic method. The speed and precision of computation are restricted. In this paper, a software to calculate water surface profile is introduced. The software is put forward by using C++ .By means of interpolate method and dialogue between user and computer, we can calculate the water surface profile much more quickly and exactly. 展开更多
关键词 non-uniform flow water surface profile COMPUTER
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Effects of the Trade and Financial Governmental Policies on the Total Investment in Syria (1980-2010)
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作者 AlaaDayoub fuqiang 《Chinese Business Review》 2017年第3期109-125,共17页
This paper attempts to investigate the effects of several financial and trade policies on the total investment in Syria, over the period 1980-2010 (before the current war). The study employs Johansen co-integration ... This paper attempts to investigate the effects of several financial and trade policies on the total investment in Syria, over the period 1980-2010 (before the current war). The study employs Johansen co-integration test to check the presence of long-term relationship between explanatory and dependent variables. In addition, Vector Error Correction Model (VECM) further studies the causal relationship from dependent variable to independent variables. The Johansen co-integration test indicates a significant long-term relationship among the variables. Moreover, the Vector Error Correction Model also suggests the long run causality from the imports, exports, capital public expenditures, and subsidies to total investment. The study’s result indicates that the imports and the capital public expenditures played a significant role in supporting the total investment in the country before the war, while there was a negative role of exports in the total investment, and there was no impact of subsidies on the total investment. Before the war, foreign investment in Syria was over dominated by European Union. The paper proposes to diversify the target of investment flow to Syria, especially from China and the other BRICS countries that can take advantages from Syria and can support Syria economy after the war by the strategy of “One Road One Belt”. Theseresults may assist Syrian policy makers, after the war, to develop an economic plan that takes into account the effects of these policies to improve the total investment which will help Syria in rebuilding the economy. 展开更多
关键词 trade policy financial policy total investment investment climate
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RFLP and SSR mapping of a new gene for brown planthopper resistance introgressed from O.eichingeri into cultivated rice(O.sativa L.) 被引量:2
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作者 LINGuoqing YANHuihuang +2 位作者 fuqiang QIANQian ZHULihunag 《Chinese Rice Research Newsletter》 2000年第1期2-2,共1页
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The effect of 35℃ on the amino acid requirement of the brown planthopper,Nilaparvata lugens
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作者 fuqiang ZHANGZhitao +1 位作者 LAIFenxiang HUCui 《Chinese Rice Research Newsletter》 1999年第1期4-4,共1页
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RELATION BETWEEN COHERENT STRUCTURE AND SCALING LAW IN RAYLEIGH-BENARD CONVECTION BASED ON WAVELET TRANSFORMATION
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作者 fuqiang JIANGMin XIAKe-qing 《Journal of Hydrodynamics》 SCIE EI CSCD 2004年第4期436-441,共6页
In this paper, the Extended Self Similarity (ESS) was used to study thescaling exponent ξ(q) of temperature data in the Reyleigh-Benard convection and its variation withexperimental measuring locations. The results s... In this paper, the Extended Self Similarity (ESS) was used to study thescaling exponent ξ(q) of temperature data in the Reyleigh-Benard convection and its variation withexperimental measuring locations. The results show that ξ(q) varies with locations and agrees wellwith experimental data. And then the wavelet transformation is used to extract the coherentstructure, by means of the definition of a called non-coherent signal. we can understand theinfluence of coherent structure on ξ(q) and the relations between large scale vortex motions andsmall ones. 展开更多
关键词 scaling law coherent structure wavelet transformation rayleigh-benardconvection
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