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Impact of Delivery Mode on Morbidity in Preterm Infants with Very Low Birth Weights (<1500 Grams)
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作者 Manuela Colle José Mauro Madi +2 位作者 Luciano Selistre Gabriela Françoes Rostirolla Marcelo Costamilan Rombaldi 《Open Journal of Obstetrics and Gynecology》 2024年第10期1583-1590,共8页
The mode of delivery and gestational age for very-low-birth-weight (VLBW) preterm infants are not yet well established and are constant topics of debate. Objective: To analyze the impact of delivery mode on morbidity ... The mode of delivery and gestational age for very-low-birth-weight (VLBW) preterm infants are not yet well established and are constant topics of debate. Objective: To analyze the impact of delivery mode on morbidity in preterm infants weighing less than 1500 g. Results: Among 21,957 births, 81 were analyzed;53 were delivered vaginally, and 28 were delivered by cesarean section. The median maternal age, gestational age and body mass index among those delivered vaginally and by cesarean section were 20 years and 22.5 years, 27.6 weeks and 30.1 weeks, and 26.0 kg/m2 and 27.8 kg/m2, respectively. With respect to neonatal blood gas parameters, for those born vaginally and by cesarean section, the median pH was 7.32 and 7.24, the pCO2 was 41.5 mmHg and 51.1 mmHg, and the pO2 was 22.3 mmHg and 16 mmHg. The median fetal weight among those born by cesarean section and vaginally were 1180 g and 955 g, respectively. The median Apgar scores at the first and fifth minutes among those born by cesarean section and vaginally were 5.00 and 8.00 and 4.50 and 7.00, respectively. Conclusion: There was no significant difference between the results of vaginal and cesarean delivery for VLBW infants. Thus, further studies on this subject are needed. 展开更多
关键词 PREMATURITY Very Low Birth Weight Newborns Mode of Delivery EPIDEMIOLOGY MORBIDITY
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Assessing Criteria Weights by the Symmetry Point of Criterion (Novel SPC Method)–Application in the Efficiency Evaluation of the Mineral Deposit Multi-Criteria Partitioning Algorithm
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作者 Zoran Gligoric Milos Gligoric +2 位作者 Igor Miljanovic Suzana Lutovac Aleksandar Milutinovic 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第7期955-979,共25页
Information about the relative importance of each criterion or theweights of criteria can have a significant influence on the ultimate rank of alternatives.Accordingly,assessing the weights of criteria is a very impor... Information about the relative importance of each criterion or theweights of criteria can have a significant influence on the ultimate rank of alternatives.Accordingly,assessing the weights of criteria is a very important task in solving multi-criteria decision-making problems.Three methods are commonly used for assessing the weights of criteria:objective,subjective,and integrated methods.In this study,an objective approach is proposed to assess the weights of criteria,called SPCmethod(Symmetry Point of Criterion).This point enriches the criterion so that it is balanced and easy to implement in the process of the evaluation of its influence on decision-making.The SPC methodology is systematically presented and supported by detailed calculations related to an artificial example.To validate the developed method,we used our numerical example and calculated the weights of criteria by CRITIC,Entropy,Standard Deviation and MEREC methods.Comparative analysis between these methods and the SPC method reveals that the developedmethod is a very reliable objective way to determine the weights of criteria.Additionally,in this study,we proposed the application of SPCmethod to evaluate the efficiency of themulti-criteria partitioning algorithm.The main idea of the evaluation is based on the following fact:the greater the uniformity of the weights of criteria,the higher the efficiency of the partitioning algorithm.The research demonstrates that the SPC method can be applied to solving different multi-criteria problems. 展开更多
关键词 Multi-criteria decision-making weights of criteria symmetry point of criterion mineral deposit partitioning algorithm performance evaluation
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Inter-Provincial Transaction Model in Two-Level ElectricityMarket Considering Carbon Emission and Consumption Responsibility Weights
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作者 Chunlei Jiao HongyanHao +4 位作者 Ming Li Rifucairen Fu Yichun Liu Shunfu Lin Ronghui Liu 《Energy Engineering》 EI 2023年第10期2393-2416,共24页
In the context of the joint operation of China’s intra-provincial markets and inter-provincial trading,how to meet the load demand and energy consumption using inter-provincial renewable energy trading is a key probl... In the context of the joint operation of China’s intra-provincial markets and inter-provincial trading,how to meet the load demand and energy consumption using inter-provincial renewable energy trading is a key problem.The combined operation of intra-provincial and inter-provincial markets provides a new way for provincial power companies to optimize and clear the intra-provincial power market,complete the intra-provincial consumption responsibility weight index,and consume renewable energy across provinces and regions.This paper combines power generation and consumption within the province,uses inter-provincial renewable energy trading tomeet the load demand within the province and completes the index of intra-provincial consumption responsibility weights.The intra-provincial market trading and inter-provincial market clearing are respectively taken as the upper and lower levels of the model.Under the two-level electricity market operation framework,the upper-level model aims to minimize the expected total operating cost within the province considering the carbon emission cost and the weight of the consumption responsibility,while the lower-level model aims to minimize the inter-provincial renewable energy purchasing cost.Finally,the influence of inter-provincial transaction mechanism,risk aversion coefficient,voucher price,and responsibility weight on operating cost is analyzed.Simulation is used to verify that the proposed model can meet the requirements of the provincial load power consumption and the consumption responsibility weight index,and promote the consumption of renewable energy. 展开更多
关键词 Consumption responsibility weights electricity market carbon emission transactions between provinces
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Utilizing OSA-modified starch with various molecular weights for flavonoid extraction from"Quzhiqiao"(immature fruit of Citrus paradisi'Changshan Huyou')
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作者 Lu Wang Xuyi Zhou +3 位作者 Shengmin Lu Siew Young Quek Juzhao Liu Qi Cui 《Beverage Plant Research》 2023年第1期280-286,共7页
In order to investigate the extraction efficiency of flavonoids by octenyl succinic acid-modified starch(OSA-modified starch)with varying molecular weights,the immature fruit of Citrus paradisi'Changshan Huyou'... In order to investigate the extraction efficiency of flavonoids by octenyl succinic acid-modified starch(OSA-modified starch)with varying molecular weights,the immature fruit of Citrus paradisi'Changshan Huyou',commonly known as"Quzhiqiao",was used as the extraction target in this research.OSA-modified starch was successfully identified and refined,ensuring its molecular weight was appropriate and extraction was optimized.The experimental findings suggested that a concentration of 20 mg/mL of medium molecular weight gelatinized OSA-modified starch was optimal for extracting flavonoids from"Quzhiqiao"using an ultrasound-assisted method(1,000 W,40 min).Additionally,the ratio of the mass of"Quzhiqiao"to the volume of gelatinized OSA-modified starch employed in this process was determined to be 15 mg/mL.The findings from the in vitro antioxidant studies indicated significant variations in the antioxidant activities of the extract solutions of OSA-modified starches with varying molecular weights.These differences can potentially be attributed to substantial variations in the extract solutions composition. 展开更多
关键词 weights STARCH modified
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Structural characterizations andα-glucosidase inhibitory activities of four Lepidium meyenii polysaccharides with different molecular weights
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作者 Luan Wen Zhou-Wei Wu +3 位作者 Li-Wu Lin Abdulbaset Al-Romaima Xing-Rong Peng Ming-Hua Qiu 《Natural Products and Bioprospecting》 CSCD 2023年第1期568-576,共9页
Four polysaccharides(MCPa,MCPb,MCPc,MCPd)were obtained from Lepidium meyenii Walp.Their structures were characterized by chemical and instrumental methods including total sugar,uronic acid and protein content determi-... Four polysaccharides(MCPa,MCPb,MCPc,MCPd)were obtained from Lepidium meyenii Walp.Their structures were characterized by chemical and instrumental methods including total sugar,uronic acid and protein content determi-nation,UV,IR and NMR spectroscopy,as well as monosaccharide composition determination and methylation analy-ses.Four polysaccharides were a group of glucans with different molecular weights ranging from 3.12 to 14.4 kDa,and shared a similar backbone chain consisting of(1→4)-glucose linkages with branches attached to C-3 and C-6.Furthermore,bioactivity assay showed that MCPs had concentration-dependent inhibitory activity onα-glucosidase.MCPb(Mw=10.1 kDa)and MCPc(Mw=5.62 kDa)with moderate molecular weights exhibited higher inhibitory activ-ity compared with MCPa and MCPd. 展开更多
关键词 Lepidium meyenii POLYSACCHARIDE Molecular weight Structural characterization α-Glucosidase inhibition
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Unsupervised Functional Data Clustering Based on Adaptive Weights
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作者 Yutong Gao Shuang Chen 《Open Journal of Statistics》 2023年第2期212-221,共10页
In recent years, functional data has been widely used in finance, medicine, biology and other fields. The current clustering analysis can solve the problems in finite-dimensional space, but it is difficult to be direc... In recent years, functional data has been widely used in finance, medicine, biology and other fields. The current clustering analysis can solve the problems in finite-dimensional space, but it is difficult to be directly used for the clustering of functional data. In this paper, we propose a new unsupervised clustering algorithm based on adaptive weights. In the absence of initialization parameter, we use entropy-type penalty terms and fuzzy partition matrix to find the optimal number of clusters. At the same time, we introduce a measure based on adaptive weights to reflect the difference in information content between different clustering metrics. Simulation experiments show that the proposed algorithm has higher purity than some algorithms. 展开更多
关键词 Functional Data Unsupervised Learning Clustering Functional Principal Component Analysis Adaptive Weight
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NEW SHADOWED C-MEANS CLUSTERING WITH FEATURE WEIGHTS 被引量:2
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作者 王丽娜 王建东 姜坚 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2012年第3期273-283,共11页
Partition-based clustering with weighted feature is developed in the framework of shadowed sets. The objects in the core and boundary regions, generated by shadowed sets-based clustering, have different impact on the ... Partition-based clustering with weighted feature is developed in the framework of shadowed sets. The objects in the core and boundary regions, generated by shadowed sets-based clustering, have different impact on the prototype of each cluster. By integrating feature weights, a formula for weight calculation is introduced to the clustering algorithm. The selection of weight exponent is crucial for good result and the weights are updated iteratively with each partition of clusters. The convergence of the weighted algorithms is given, and the feasible cluster validity indices of data mining application are utilized. Experimental results on both synthetic and real-life numerical data with different feature weights demonstrate that the weighted algorithm is better than the other unweighted algorithms. 展开更多
关键词 fuzzy C-means shadowed sets shadowed C-means feature weights cluster validity index
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Some OWA operator weights determination methods with RIM quantifier
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作者 刘新旺 《Journal of Southeast University(English Edition)》 EI CAS 2007年第S1期76-82,共7页
Based on the quantifier guided method,an ordered weighted averaging(OWA)weights generating method under given orness level with regular increasing monotone(RIM)quantifiers is proposed.Then the RIM quantifier based OWA... Based on the quantifier guided method,an ordered weighted averaging(OWA)weights generating method under given orness level with regular increasing monotone(RIM)quantifiers is proposed.Then the RIM quantifier based OWA weights generating method is modified to make the generated weights be monotonic,which can be used to express the decision maker's consistent preference information.Finally,both of these weights generating methods are extended to their generic forms,so that they can generate the OWA weights for any ordinary elements set with any given aggregated value. 展开更多
关键词 ordered weighted averaging operator orness measure aggregation weights
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On Turán type inequality with doubling weights and A weights
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作者 虞旦盛 韦宝荣 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第7期764-768,共5页
Let Hn be the set of real algebraic polynomials of degree n, whose zeros all lie in the interval [-1,1]. The well known Turán type inequalities tell us that forf(x)∈Hn, it holds ‖f'‖≥C√n‖f‖. This note d... Let Hn be the set of real algebraic polynomials of degree n, whose zeros all lie in the interval [-1,1]. The well known Turán type inequalities tell us that forf(x)∈Hn, it holds ‖f'‖≥C√n‖f‖. This note deals with the weighted Turán type inequalities with the weights having inner singularities under L^p norm for 0〈p≤∞. Our results essentially extend the result of Wang and Zhou (2002), and the method used in this paper is simpler and more direct than that of Wang and Zhou (2002). The results and methods have their own values in approximation theory and computation. 展开更多
关键词 Turán type inequality Doubling weights A weights
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Spatial assessment for groundwater quality based on GIS and improved fuzzy comprehensive assessment with entropy weights 被引量:4
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作者 Jingwei Hou 《Chinese Journal of Population,Resources and Environment》 2013年第2期135-141,共7页
The objective of the research is to evaluate spatial groundwater quality based on improved fuzzy comprehensive assessment model with entropy weights(FCAEW)in geographical information system(GIS)environment.This paper ... The objective of the research is to evaluate spatial groundwater quality based on improved fuzzy comprehensive assessment model with entropy weights(FCAEW)in geographical information system(GIS)environment.This paper explores the method of comprehensive evaluation of groundwater and sets up an evaluation model applying GIS and FCAEW.Groundwater samples were collected and analyzed from 29 wells in Zhenping County,China.Six parameters were chosen including chloride,sulfate,total hardness,nitrate,fluoride and color.Better spatial interpolation methods for evaluated parameters are found out and selected according to the minimum cross-validation errors from the interpolation methods.FCAEW model was carried out with the help of GIS which makes the evaluating process simpler and easier and more automatically,effectively,efficiently and intelligently.The result embodies the feasibility and effectiveness of FCAEW in GIS when compared with other comprehensive evaluation methods. 展开更多
关键词 GEOGRAPHICAL information system(GIS) fuzzy comprehensive assessment(FCA) ENTROPY weights quality evaluation GROUNDWATER
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Linear goal programming approach to obtaining the weights of intuitionistic fuzzy ordered weighted averaging operator 被引量:3
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作者 Yejun Xu Chao Huang +1 位作者 Qingli Da Xinwang Liu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第6期990-994,共5页
The multiple attribute decision making problems are studied, in which the information about attribute weights is partly known and the attribute values take the form of intuitionistic fuzzy numbers. The operational law... The multiple attribute decision making problems are studied, in which the information about attribute weights is partly known and the attribute values take the form of intuitionistic fuzzy numbers. The operational laws of intuitionistic fuzzy numbers are introduced, and the score function and accuracy function are presented to compare the intuitionistic fuzzy numbers. The intuitionistic fuzzy ordered weighted averaging (IFOWA) operator which is an extension of the well-known ordered weighted averaging (OWA) operator is investigated to aggregate the intuitionistic fuzzy information. In order to determine the weights of intuitionistic fuzzy ordered weighted averaging operator, a linear goal programming procedure is proposed for learning the weights from data. Finally, an example is illustrated to verify the effectiveness and practicability of the developed method. 展开更多
关键词 intuitionistic fuzzy set intuitionistic fuzzy ordered weighted averaging(IFOWA) operator linear goal programming weights multiple attribute decision making(MADM).
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Self-determinate evaluation method based on condition of weights non-dictatorial rate 被引量:3
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作者 Zhang Danning Yi Pingtao Guo Yajun 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第2期310-320,共11页
The condition of weightes non-dictatorship is extended and a comprehensive evaluae method emboding self-determinate which is combined with competitive view optimization principles is built. The basic process includes ... The condition of weightes non-dictatorship is extended and a comprehensive evaluae method emboding self-determinate which is combined with competitive view optimization principles is built. The basic process includes simulating the model of economic man's self-benefit bahaviors, taking the place of experts to evaluate, bringing in the model of minimizing the sum of included angles to integrate the information of multiple objects and put the objects in order finally. The method has the advangtages of less dependendence on the subjective information, plenty of information, fair process and simple caculating. Finally, an application example is given to illustrate the effectiveness of the proposed method. 展开更多
关键词 condition of weights non-dictatorial rate principle of competitive view optimization self-determinate evaluation comprehensive evaluation
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Using Fuzzy Theory and Variable Weights for Water Quality Evaluation in Poyang Lake, China 被引量:16
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作者 LI Bing YANG Guishan +3 位作者 WAN Rongrong ZHANG Lu ZHANG Yanhui DAI Xue 《Chinese Geographical Science》 SCIE CSCD 2017年第1期39-51,共13页
Achieving water purity in Poyang Lake has become a major concern in recent years, thus appropriate evaluation of spatial and temporal water quality variations has become essential. Variations in 11 water quality param... Achieving water purity in Poyang Lake has become a major concern in recent years, thus appropriate evaluation of spatial and temporal water quality variations has become essential. Variations in 11 water quality parameters from 15 sampling sites in Poyang Lake were investigated from 2009 to 2012. An integrative fuzzy variable evaluation(IFVE) model based on fuzzy theory and variable weights was developed to measure variations in water quality. Results showed that: 1) only chlorophyll-a concentration and Secchi depth differed significantly among the 15 sampling sites(P < 0.01), whereas the 11 water quality parameters under investigation differed significantly throughout the seasons(P < 0.01). The annual variations of all water quality variables except for temperature, electrical conductivity, suspended solids and total phosphorus were considerable(P < 0.05). 2) The IFVE model was reasonable and flexible in evaluating water quality status and any possible ′bucket effect′. The model fully considered the influences of extremely poor indices on overall water quality. 3) A spatial analysis indicated that anthropogenic activities(particularly industrial sewage and dredging) and lake bed topography might directly affect water quality in Poyang Lake. Meanwhile, hydrological status and sewage discharged into the lake might be responsible for seasonal water quality variations. 展开更多
关键词 fuzzy theory bucket effect variable weights water quality Poyang Lake
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GIS Predictive Model for Producing Hydrothermal Gold Potential Map Using Weights of Evidence Approach in Gengma Region, Sanjiang District, China 被引量:3
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作者 Bassam F Al Bassam 《Journal of China University of Geosciences》 SCIE CSCD 2003年第3期283-292,共10页
Gengma region, Sanjiang district is known to have some large-scale gold deposits. GIS predictive model for hydrothermal gold potential was carried out in this region using weights of evidence modeling technique. Datas... Gengma region, Sanjiang district is known to have some large-scale gold deposits. GIS predictive model for hydrothermal gold potential was carried out in this region using weights of evidence modeling technique. Datasets used include large-scale hydrothermal gold deposit records, geological, geophysical and remote sensing imagery. Based on the geological and mineral characteristics of areas with known gold occurrences in Sanjiang, several geological features were thought to be indicative of areas with potential for the occurrence of hydrothermal gold deposits. Indicative features were extracted from geoexploration datasets for use as input in the predictive model. The features include host rock lithology, geologic structures, wallrock alteration and associated (volcanic-plutonic) igneous rocks. To determine which of the indicative geological features are important spatial predictors of area with potential for gold deposits, spatial analysis was done through the modeling method. The input maps were buffered and the optimum distance of spatial association for each geological feature was determined by calculating the contrast and studentized contrast. Five feature maps were converted to binary predictor patterns and used as evidential layers for predictive modeling. The binary patterns were integrated in two combinations, each of which consists of four patterns in order to avoid over prediction due to the effect of duplicate features in the two structural evidences. The two produced potential maps define almost similar favorable zones. Areas of intersections between these zones in the two potential maps placed the highest predictive favorable zones in the region. 展开更多
关键词 geographic information system weights of evidence mineral resource prediction Sanjiang district
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Approach to obtaining weights of uncertain ordered weighted geometric averaging operator 被引量:1
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作者 许叶军 达庆利 《Journal of Southeast University(English Edition)》 EI CAS 2008年第1期110-113,共4页
The ordered weighted geometric averaging(OWGA) operator is extended to accommodate uncertain conditions where all input arguments take the forms of interval numbers. First, a possibility degree formula for the compa... The ordered weighted geometric averaging(OWGA) operator is extended to accommodate uncertain conditions where all input arguments take the forms of interval numbers. First, a possibility degree formula for the comparison between interval numbers is introduced. It is proved that the introduced formula is equivalent to the existing formulae, and also some desired properties of the possibility degree is presented. Secondly, the uncertain OWGA operator is investigated in which the associated weighting parameters cannot be specified, but value ranges can be obtained and the associated aggregated values of an uncertain OWGA operator are known. A linear objective-programming model is established; by solving this model, the associated weights vector of an uncertain OWGA operator can be determined, and also the estimated aggregated values of the alternatives can be obtained. Then the alternatives can be ranked by the comparison of the estimated aggregated values using the possibility degree formula. Finally, a numerical example is given to show the feasibility and effectiveness of the developed method. 展开更多
关键词 interval numbers uncertain ordered weighted geometric averaging operator possibility degree
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The statistical observation localized equivalent-weights particle filter in a simple nonlinear model 被引量:2
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作者 Yuxin Zhao Shuo Yang +4 位作者 Renfeng Jia Di Zhou Xiong Deng Chang Liu Xinrong Wu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2022年第2期80-90,共11页
This paper presents an improved approach based on the equivalent-weights particle filter(EWPF)that uses the proposal density to effectively improve the traditional particle filter.The proposed approach uses historical... This paper presents an improved approach based on the equivalent-weights particle filter(EWPF)that uses the proposal density to effectively improve the traditional particle filter.The proposed approach uses historical data to calculate statistical observations instead of the future observations used in the EWPF’s proposal density and draws on the localization scheme used in the localized PF(LPF)to construct the localized EWPF.The new approach is called the statistical observation localized EWPF(LEWPF-Sobs);it uses statistical observations that are better adapted to the requirements of real-time assimilation and the localization function is used to calculate weights to reduce the effect of missing observations on the weights.This approach not only retains the advantages of the EWPF,but also improves the assimilation quality when using sparse observations.Numerical experiments performed with the Lorenz 96 model show that the statistical observation EWPF is better than the EWPF and EAKF when the model uses standard distribution observations.Comparisons of the statistical observation localized EWPF and LPF reveal the advantages of the new method,with fewer particles giving better results.In particular,the new improved filter performs better than the traditional algorithms when the observation network contains densely spaced measurements associated with model state nonlinearities. 展开更多
关键词 data assimilation particle filter equivalent weights particle filter localization methods
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An Active Anti-Jamming Approach for Frequency Diverse Array Radar with Adaptive Weights 被引量:2
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作者 Yibin Liu Chunyang Wang +1 位作者 Guimei Zheng Jian Gong 《Journal of Beijing Institute of Technology》 EI CAS 2021年第4期403-411,共9页
Due to the rapid development of electronic countermeasures(ECMs),the corresponding means of electronic counter countermeasures(ECCMs)are urgently needed.In this paper,an act-ive anti-jamming method based on frequency ... Due to the rapid development of electronic countermeasures(ECMs),the corresponding means of electronic counter countermeasures(ECCMs)are urgently needed.In this paper,an act-ive anti-jamming method based on frequency diverse array radar is proposed.By deriving the closed form of the phase center in a uniform line array FDA,we establish a model of the FDA signal based on adaptive weights and derive the effect of active anti-jamming in this regime.The pro-posed active anti-jamming method makes it difficult for jammers to detect or locate our radar.Fur-thermore,the effectiveness of the two frequency increment schemes in terms of anti-jamming is ana-lyzed by comparing the deviation of phase center.Finally,the simulation results verify the effective-ness and superiority of the proposed method. 展开更多
关键词 frequency diverse array(FDA) active anti-jamming adaptive weights phase center deviation
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EXPLICIT SOLUTIONS OF THE OPTIMUM WEIGHTS OF LAYERED NEURAL NETWORKS 被引量:1
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作者 尤肖虎 《Journal of Southeast University(English Edition)》 EI CAS 1992年第1期39-45,共7页
It is shown in this paper that if the hidden layer units take a sinusoidalactivation function,the optimum weights of the three-layer feedforward neural networkcan be explicitly solved by relating the layered neural ne... It is shown in this paper that if the hidden layer units take a sinusoidalactivation function,the optimum weights of the three-layer feedforward neural networkcan be explicitly solved by relating the layered neural network with a truncated Fourier se-ries expansion.Based on this result,two approaches are presented of which one is suited tothe case that the detailed statistical information is available or can be easily estimated.An-other is of data-adaptive type,which can be treated as a solution of standardleast-squares.The later is best suited to realtime processing and slowly time-varying ap-plications since it can be straightforwardly implemented by the traditional LMS or RLSadaptive algorithms.It is also shown that for both the approaches,the resulting networksown an ability of forming arbitrary mappings.By using the present approaches,theconventional training procedure,which is usually very time-consuming,can be avoided. 展开更多
关键词 neurel NETWORKS adaptive FILTERING optimization methods/backpropagation ncurcl NETWORKS OPTIMUM weights
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Degenerations of rational Bézier surface with weights in the form of exponential function 被引量:1
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作者 ZHANG Yue ZHU Chun-gang GUO Qing-jie 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2017年第2期164-182,共19页
Rational Bezier surface is a widely used surface fitting tool in CAD. When all the weights of a rational B@zier surface go to infinity in the form of power function, the limit of surface is the regular control surface... Rational Bezier surface is a widely used surface fitting tool in CAD. When all the weights of a rational B@zier surface go to infinity in the form of power function, the limit of surface is the regular control surface induced by some lifting function, which is called toric degenerations of rational Bezier surfaces. In this paper, we study on the degenerations of the rational Bezier surface with weights in the exponential function and indicate the difference of our result and the work of Garcia-Puente et al. Through the transformation of weights in the form of exponential function and power function, the regular control surface of rational Bezier surface with weights in the exponential function is defined, which is just the limit of the surface. Compared with the power function, the exponential function approaches infinity faster, which leads to surface with the weights in the form of exponential function degenerates faster. 展开更多
关键词 rational Bezier surface weights regular control surface toric degenerations exponential function.
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Omnibus Weights of Evidence Method Implemented in GeoDAS GIS for Information Extraction and Integration 被引量:1
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作者 张生元 成秋明 陈志军 《Journal of China University of Geosciences》 SCIE CSCD 2008年第4期404-409,共6页
Weights of evidence (WofE) is an artificial intelligent method for integration of information from diverse sources for predictive purpose in supporting decision making. This method has been commonly used to predict ... Weights of evidence (WofE) is an artificial intelligent method for integration of information from diverse sources for predictive purpose in supporting decision making. This method has been commonly used to predict point events by integrating point training layer and binary or ternary evidential layers (multiclass evidence less commonly used). Omnibus weights of evidence integrates fuzzy training layer and diverse evidential layers. This method provides new features in comparison with the ordinary Wore method. This new method has been implemented in a geographic information system-geophysical data analysis system and the method includes the following contents: (1) dual fuzzy weights of evidence (DFWofE), in which training layer and evidential layers can be treated as fuzzy sets. DFWofE can be used to predict not only point events but also area or line events. In this model a fuzzy training layer can be defined based on point, line, and areas using fuzzy membership function; and (2) degree-of-exploration model for WorE is implemented through building a degree of exploration map. This method can be used to assess possible spatial correlations between the degree of exploration and potential evidential layers. Importantly, it would also make it possible to estimate undiscovered resources, if the degree of exploration map is combined with other models that predict where such resources are most likely to occur. These methods and relevant systems were vafidated using a case study of mineral potential prediction in Gejiu (个旧) mineral district, Yunnan ( 云南), China. 展开更多
关键词 weights of evidence fuzzy set degree of exploration GIS GeoDAS
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