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Combinations of Right Half-Plane Mappings and Vertical Strip Mappings Convex in the Vertical Direction
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作者 Yulin Cai Zirun She +1 位作者 Fanji Zeng Lu Huang 《Open Journal of Statistics》 2023年第6期941-954,共14页
In this paper, we explore the linear combinations of right half-plane mappings and vertical strip mappings. We demonstrate that the combinations of these harmonic mappings are convex in the vertical direction provided... In this paper, we explore the linear combinations of right half-plane mappings and vertical strip mappings. We demonstrate that the combinations of these harmonic mappings are convex in the vertical direction provided they are locally univalent and sense-preserving. Furthermore, we extend this analysis to a more general case by setting specific conditions. Additionally, we take some common parameters such as  as the dilatation of these harmonic mappings, and prove the sufficient conditions that their combinations are locally univalent and convex in the vertical direction. Several examples are constructed by the Mathematica software to demonstrate our main results. 展开更多
关键词 Harmonic Mapping linear combination Cohn’s Rules Directional Convexi-ty
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Firey linear combinations of convex bodies
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作者 熊革 肖启名 CHEUNG Wing-Sum 《Journal of Shanghai University(English Edition)》 CAS 2009年第2期102-104,共3页
For convex bodies, the Firey linear combinations were introduced and studied in several papers. In this paper the mean width of the Firey linear combinations of convex bodies is studied, and the lower bound of the mea... For convex bodies, the Firey linear combinations were introduced and studied in several papers. In this paper the mean width of the Firey linear combinations of convex bodies is studied, and the lower bound of the mean width of the Firey linear combinations of convex body and its polar body is given. 展开更多
关键词 convex body Firey linear combination mean width
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The Average Errors for Linear Combinations of Bernstein Operators on the Wiener Space
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作者 Yanjie Jiang Ziqing Zhang 《Journal of Data Analysis and Information Processing》 2013年第4期85-89,共5页
In this paper, we discuss the average errors of function approximation by linear combinations of Bernstein operators. The strongly asymptotic orders for the average errors of the combinations of Bernstein operators se... In this paper, we discuss the average errors of function approximation by linear combinations of Bernstein operators. The strongly asymptotic orders for the average errors of the combinations of Bernstein operators sequence are determined on the Wiener space. 展开更多
关键词 linear combinations BERNSTEIN OPERATORS Weighted -Norm AVERAGE Error WIENER Space
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EXPLICIT VORONOVSKAJA-TYPE RESULTS FOR LINEAR COMBINATIONS OF BDT-OPERATORS
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作者 M. Heilmann 《Analysis in Theory and Applications》 1995年第1期54-61,共8页
In this paper me prove an explicit Vcionovskvja-type result for linear combmations of the so-called BDT -operators.
关键词 EXPLICIT VORONOVSKAJA-TYPE RESULTS FOR linear combinations OF BDT-OPERATORS
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Combined model based on optimized multi-variable grey model and multiple linear regression 被引量:11
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作者 Pingping Xiong Yaoguo Dang +1 位作者 Xianghua wu Xuemei Li 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2011年第4期615-620,共6页
The construction method of background value is improved in the original multi-variable grey model (MGM(1,m)) from its source of construction errors. The MGM(1,m) with optimized background value is used to elimin... The construction method of background value is improved in the original multi-variable grey model (MGM(1,m)) from its source of construction errors. The MGM(1,m) with optimized background value is used to eliminate the random fluctuations or errors of the observational data of all variables, and the combined prediction model together with the multiple linear regression is established in order to improve the simulation and prediction accuracy of the combined model. Finally, a combined model of the MGM(1,2) with optimized background value and the binary linear regression is constructed by an example. The results show that the model has good effects for simulation and prediction. 展开更多
关键词 multi-variable grey model (MGM(1 m)) backgroundvalue OPTIMIZATION multiple linear regression combined predic-tion model.
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Using GIS-Based Weighted Linear Combination Analysis and Remote Sensing Techniques to Select Optimum Solid Waste Disposal Sites within Mafraq City, Jordan 被引量:5
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作者 Ahmad Al-Hanbali Bayan Alsaaideh Akihiko Kondoh 《Journal of Geographic Information System》 2011年第4期267-278,共12页
Landfill siting was determined within Mafraq City, Jordan, through the integration of geographic information system (GIS), weighted linear combination (WLC) analysis, and remote sensing techniques. Several parameters ... Landfill siting was determined within Mafraq City, Jordan, through the integration of geographic information system (GIS), weighted linear combination (WLC) analysis, and remote sensing techniques. Several parameters were collected from various sources in vector and raster GIS formats, and then, used within the GIS-based WLC analysis to select optimum solid waste disposal sites. Namely, urban areas, agricultural lands, access roads, surface aquifers, groundwater table, fault system, water wells, streams, and land slope were considered in this research. Also, the trend of urban expansion within the study area was monitored using the Landsat data of 1989, 1999, and 2009 to support the selection process of disposal sites. It is found that about 84% of the study area was within “most suitable” to “moderately suitable” classes for landfill sites, while the rest of the study area was within “poorly suitable” and “unsuitable” classes. Based on the analysis of Landsat satellite data the urban area was expanded of more than 240% during the last three decades, mainly toward south, and southwest, except the villages near the existing disposal site, where the trend was toward east and northeast. Finally, three sites were suggested as alternatives to the existing disposal site taking into the consideration the environmental, biophysical, and economical variables applied in the GIS-based WLC analysis. 展开更多
关键词 SOLID Waste WEIGHTED linear combination GIS Remote Sensing JORDAN
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Quadratic Stabilization of Switched Uncertain Linear Systems: A Convex Combination Approach 被引量:3
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作者 Yufang Chang Guisheng Zhai +1 位作者 Bo Fu Lianglin Xiong 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2019年第5期1116-1126,共11页
We consider quadratic stabilization for a class of switched systems which are composed of a finite set of continuoustime linear subsystems with norm bounded uncertainties. Under the assumption that there is no single ... We consider quadratic stabilization for a class of switched systems which are composed of a finite set of continuoustime linear subsystems with norm bounded uncertainties. Under the assumption that there is no single quadratically stable subsystem, if a convex combination of subsystems is quadratically stable, then we propose a state-dependent switching law, based on the convex combination of subsystems, such that the entire switched linear system is quadratically stable. When the state information is not available, we extend the discussion to designing an outputdependent switching law by constructing a robust Luenberger observer for each subsystem. 展开更多
关键词 CONVEX combination limear matrix INEQUALITIES (LMIs) norm BOUNDED uncertainties output-dependent switching quadratic stabilization state-dependent SWITCHING SWITCHED uncertain linear systems(SULS)
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Short-Term Scheduling of Combined Cycle Units Using Mixed Integer Linear Programming Solution 被引量:1
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作者 Juan Alemany Diego Moitre +1 位作者 Herminio Pinto Fernando Magnago 《Energy and Power Engineering》 2013年第2期161-170,共10页
Combined cycle plants (CCs) are broadly used all over the world. The inclusion of CCs into the optimal resource scheduling causes difficulties because they can be operated in different operating configuration modes ba... Combined cycle plants (CCs) are broadly used all over the world. The inclusion of CCs into the optimal resource scheduling causes difficulties because they can be operated in different operating configuration modes based on the number of combustion and steam turbines. In this paper a model CCs based on a mixed integer linear programming approach to be included into an optimal short term resource optimization problem is presented. The proposed method allows modeling of CCs in different modes of operation taking into account the non convex operating costs for the different combined cycle mode of operation. 展开更多
关键词 combined CYCLE PLANTS Unit COMMITMENT MIXED INTEGER linear PROGRAMMING
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A Linear Combination of Superderivations on Prime Superalgebras 被引量:1
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作者 袁鹤 《Northeastern Mathematical Journal》 CSCD 2008年第5期399-408,共10页
In the paper, we give some results about a linear combination of superderivations on prime superalgebras and generalize a result of Niu Feng-wen.
关键词 prime superalgebra SUPERDERIVATION linear combination
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Revisiting ENSO impacts on the Indian Ocean SST based on a combined linear regression method 被引量:1
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作者 Lianyi Zhang Yan Du +1 位作者 Tomoki Tozuka Shoichiro Kido 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2021年第5期47-57,共11页
The El Nino-Southern Oscillation(ENSO)has great impacts on the Indian Ocean sea surface temperature(SST).In fact,two major modes of the Indian Ocean SST namely the Indian Ocean Basin(IOB)and the Indian Ocean Dipole(IO... The El Nino-Southern Oscillation(ENSO)has great impacts on the Indian Ocean sea surface temperature(SST).In fact,two major modes of the Indian Ocean SST namely the Indian Ocean Basin(IOB)and the Indian Ocean Dipole(IOD)modes,exerting strong influences on the Indian Ocean rim countries,are both influenced by the ENSO.Based on a combined linear regression method,this study quantifies the ENSO impacts on the IOB and the IOD during ENSO concurrent,developing,and decaying stages.After removing the ENSO impacts,the spring peak of the IOB disappears along with significant decrease in number of events,while the number of events is only slightly reduced and the autumn peak remains for the IOD.By isolating the ENSO impacts during each stage,this study reveals that the leading impacts of ENSO contribute to the IOD development,while the delayed impacts facilitate the IOD phase switch and prompt the IOB development.Besides,the decadal variations of ENSO impacts are various during each stage and over different regions.These imply that merely removing the concurrent ENSO impacts would not be sufficient to investigate intrinsic climate variability of the Indian Ocean,and the present method may be useful to study climate variabilities independent of ENSO. 展开更多
关键词 Indian Ocean ENSO sea surface temperature climate modes combined linear regression
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Generation of Linear Isolated Sub-60 Attosecond Pulses by Combining a Circularly Polarized Pulse with an Elliptically Polarized Pulse 被引量:1
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作者 夏昌龙 苗向阳 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第4期38-41,共4页
The two-color circularly polarized pulses scheme was proposed to generate isolated attosecond pulses in our previous work [Phys. Rev. A 87 (2013) 043406], while the polarization of the attosecond pulse was not inves... The two-color circularly polarized pulses scheme was proposed to generate isolated attosecond pulses in our previous work [Phys. Rev. A 87 (2013) 043406], while the polarization of the attosecond pulse was not investigated. We show a supplementary explanation of this scheme and present another scheme to generate linear isolated attosecond pulses by combining a circularly polarized pulse with an elliptically polarized pulse. High-order harmonic generation and quantum path control are investigated to compare these two schemes. Both schemes can obtain supercontinuum spectra plateau from about 200eV to 550eV, which belong to the water window region. It is found that the latter scheme can clearly eliminate the short quantum path and extend the harmonic plateau. A linear isolated attosecond pulse with a duration of sub-6Oas can be generated by superposing a bandwidth of 70eV. 展开更多
关键词 Generation of linear Isolated Sub-60 Attosecond Pulses by combining a Circularly Polarized Pulse with an Elliptically Polarized Pulse
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Quantitative analysis of glutamate compounds in the swine brain following central analgesics nasal spray using proton magnetic resonance spectroscopy and linear combination model
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作者 Jianlin Wu Ting Liu +4 位作者 Yan Lin Zhiwei Shen Yanwei Miao Renhua Wu Changkai Sun 《Neural Regeneration Research》 SCIE CAS CSCD 2009年第7期508-512,共5页
BACKGROUND: In localized brain proton magnetic resonance spectroscopy (^1H-MRS), metabolite levels are often expressed as ratios, rather than absolute concentrations. Frequently, the denominator is creatine, which ... BACKGROUND: In localized brain proton magnetic resonance spectroscopy (^1H-MRS), metabolite levels are often expressed as ratios, rather than absolute concentrations. Frequently, the denominator is creatine, which is assumed to be stable in normal, as well as many pathological, states. However, in vivo creatine levels do not remain constant. Therefore, absolute metabolite measurements, which provide the precise concentrations of certain chemical compounds, are superior to metabolite ratios for determining pathological and evolutional changes. OBJECTIVE: To investigate the feasibility of quantification analysis of brain metabolite changes caused by central analgesics nasal spray using the ^1H-MRS and linear combination model (LCModel) methods. DESIGN, TIME AND SETTING: This neuroimaging, observational, animal study was performed at the Laboratory of the Department of Medical Imaging, Second Affiliated Hospital, Medical College, Shantou University, China from July to December 2007. MATERIALS: Butorphanol tartrate nasal spray, as a mixed agonist-antagonist opioid analgesic, was purchased from Shanghai Hengrui Pharmacy, China. A General Electric Signa 1.5T System (General Electric Medical Systems, Milwaukee, WI, USA) and LCModel software (Stephen Provencher, Oakville, Ontario, Canada) were used in this study. METHODS: MRS images were acquired in ten healthy swine aged 2 weeks using single-voxel point-resolved spectroscopic sequence. A region of interest (2 cm × 2 cm × 2 cm) was placed in the image centers of maximum brain parenchyma. Repeated MRS scanning was performed 15-20 minutes after intranasal administration of 1 mg of butorphanol tartrate. Three settings of repetition time/echo time were selected before and after nasal spray administration 3 000 ms/30 ms,1 500 ms/30 ms, and 3 000 ms/50 ms. Metabolite concentrations were estimated by LCModel software. MAIN OUTCOME MEASURES: ^1H-MRS spectra was obtained using various repetition time/echo time settings. Concentrations of glutamate compounds (glutamate + glutamine), N-acetyl aspartate, and choline were detected in swine brain prior to and following nasal spray treatment. RESULTS: The glutamate compounds curve was consistent with original spectra, when a repetition time/echo time of 3 000 ms/30 ms was adopted. Concentrations of glutamate compounds, N-acetyl aspartate, and choline decreased following administration. The most significant reduction was observed in glutamate compound concentrations from (9.28 ± 0.54) mmol/kg to (7.28 ± 0.54) mmol/kg (P 〈 0.05). CONCLUSION: ^1H-MRS and LCModel software were effectively utilized to quantitatively analyze and measure brain metabolites. Glutamate compounds might be an important neurotransmitter in central analgesia. 展开更多
关键词 proton magnetic resonance spectroscopy nasal spray linear combination model glutamate compounds absolute quantification
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Determination of Light Rare Earths by a Spectrophoto-metry Based on the Linear Combination of Multiwavelength Data
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作者 刘思东 崔秀君 +1 位作者 郭伊荇 李永涛 《Journal of Rare Earths》 SCIE EI CAS CSCD 1993年第3期211-215,共5页
The present paper proposes a new method of spectrophotometry based on linear combination of multiwavelength data by means of selecting a set of properly weighted coefficients and combination methods. It is clear that ... The present paper proposes a new method of spectrophotometry based on linear combination of multiwavelength data by means of selecting a set of properly weighted coefficients and combination methods. It is clear that the weighted combination absorbance attained is only in direct proportion to the concentration of the analysed component and independent of coexisting interferents.The accuracy of the analytical results is improved greatly for the analysis of light rare earths with the coexistence of heavy rare earths.The analyti- cal error from the reagent blank and co-coloration of light and heavy rare earths have also been overcome. The greatly improved linearity and additivity of absorbance are obtained. 展开更多
关键词 linear combination of multiwavelength data Computational spectrophotometry CPAⅢ Determination of light rare earths
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Potential Hazard Map for Snow Disaster Prevention Using GIS-Based Weighted Linear Combination Analysis and Remote Sensing Techniques: A Case Study in Northern Xinjiang, China
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作者 Gulijianati Abake Ahmad Al-Hanbali +1 位作者 Bayan Alsaaideh Ryutaro Tateishi 《Advances in Remote Sensing》 2014年第4期260-271,共12页
Snow disaster is one of the top ten natural disasters worldwide. Almost every year, there will be snow disasters in north Xinjiang, northwestern China. Since the accumulated heavy snow in winter season will seriously ... Snow disaster is one of the top ten natural disasters worldwide. Almost every year, there will be snow disasters in north Xinjiang, northwestern China. Since the accumulated heavy snow in winter season will seriously threaten people’s lives, the main object of this study is to produce a potential hazard map for snow avalanche prevention. Taking three snow seasons from November to March of year 2008 to 2010, potential hazard areas were estimated, based on snow volume products and terrain features. Remote sensing (RS) techniques and geographical information system (GIS) based weighted linear combination (WLC) approach were applied, taking into consideration multiple criteria. Snow avalanche risks were analyzed using physical exposure and vulnerability indexes. The analysis indicates that: the areas at high-risk of avalanches are located in the north and south part of the counties of Altay, Bortala and Ili prefectures;the areas at medium-risk of avalanches are found in the certain part of Altay prefecture and Urumqi, Changji, Tacheng prefectures;the avalanche risk is generally low throughout the large area to the certain part of the study area and the region on the border of the eastern north Xinjiang. Overall, the risks of snow avalanche in Altay and Ili prefectures are higher than that other regions;those areas should be allocated correspondingly more salvage materials. 展开更多
关键词 SNOW DISASTER Remote Sensing WEIGHTED linear combination NORTH XINJIANG
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Stechkin-Marchaud Type Inequalities in Lp for Linear Combination of Bernstein-Durrmeyer Operators
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作者 Feng Guo Meiqin Ke 《Open Journal of Applied Sciences》 2012年第4期228-232,共5页
In this paper, we use the equivalence relation between K-functional and modulus of smoothness, and give the Stechkin-Marchaud-type inequalities for linear combination of Bernstein-Durrmeyer operators . Moreover, we ob... In this paper, we use the equivalence relation between K-functional and modulus of smoothness, and give the Stechkin-Marchaud-type inequalities for linear combination of Bernstein-Durrmeyer operators . Moreover, we obtain the inverse result of approximation for linear combination of Bernstein-Durrmeyer operators with . Meanwhile we unify and extend some previous results. 展开更多
关键词 BERNSTEIN-DURRMEYER OPERATORS linear combination k-functional Stechkin-Marchaud-type inequalities modulus of smoothness
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Some Moments of Linear Combination of Marshall and Olinkin’s Biviariate Exponential Distribution 被引量:1
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作者 Yunfei Guo 《信息工程期刊(中英文版)》 2015年第5期12-15,共4页
关键词 马歇尔 分发 线性
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Study on the Linear Combination of a Class ofBivariate Exponential Distribution
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《数学计算(中英文版)》 2015年第2期46-49,共4页
Making use of an easier method, this paper derives the probability density function (pdf) of the linear combination of randomvariableZ =αX+βY. Furthermore, cumulative distribution function (cdf) of Z=αX+βY, ... Making use of an easier method, this paper derives the probability density function (pdf) of the linear combination of randomvariableZ =αX+βY. Furthermore, cumulative distribution function (cdf) of Z=αX+βY, where X and Y have the bivariateexponential distributions, has also been proposed in this paper. Results from this paper would have important role in the reliabilitystudy. 展开更多
关键词 linear combinATION BIVARIATE EXPONENTIAL RELIABILITY
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试验环境水下声信号的特征提取方法
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作者 王红滨 王永乐 +1 位作者 何鸣 薛垚 《哈尔滨工程大学学报》 EI CAS CSCD 北大核心 2024年第3期489-495,共7页
水下试验环境参数的反演是水声学研究领域的重要内容。而当前研究的关键是通过对水下声信号做特征提取从而获取参数信息。针对特征提取较难、模型很难拟合等问题。本文提出了一种试验环境水下声信号的特征提取方法。将水下声信号同时用... 水下试验环境参数的反演是水声学研究领域的重要内容。而当前研究的关键是通过对水下声信号做特征提取从而获取参数信息。针对特征提取较难、模型很难拟合等问题。本文提出了一种试验环境水下声信号的特征提取方法。将水下声信号同时用梅尔频谱倒谱系数及线性预测系数处理,两者运用特征加权组合方法得到新的特征矩阵;再应用映射插值算法对特征矩阵进行处理,获得适应神经网络输入的三通道矩阵。本文选取的网络模型为残差神经网络。利用实验室所录制的对河口水库数据集测试表明,本文提出的特征提取方法普遍优于仅利用梅尔频谱倒谱系数或线性预测系数的特征处理方法。利用单频矩形脉冲信号对环境进行深度5分类,准确率平均提升2%。利用线性调频信号对环境进行深度5分类,准确率平均提升2.03%。本文提出的特征提取方法对线性调频信号在深度分类任务下处理的结果要优于单频矩形脉冲信号处理的结果。 展开更多
关键词 环境反演 特征提取 梅尔频谱倒谱系数 线性预测系数 特征加权组合方法 残差神经网络 神经网络 水下声信号
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位置标签增强的中文医学命名实体级联识别
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作者 王旭阳 赵丽婕 张继远 《计算机工程与应用》 CSCD 北大核心 2024年第2期121-128,共8页
针对一般领域的命名实体识别方法不能直接用于中文医学专业实体的识别,现有的相关研究只专注于英文文本和扁平结构的医学实体识别等问题,通过对专业领域实体识别方法的研究,结合中文医学实体的特点提出了一种面向中文医学实体的级联识... 针对一般领域的命名实体识别方法不能直接用于中文医学专业实体的识别,现有的相关研究只专注于英文文本和扁平结构的医学实体识别等问题,通过对专业领域实体识别方法的研究,结合中文医学实体的特点提出了一种面向中文医学实体的级联识别方法。将每个字符元素相对于实体的位置标签嵌入模型,并结合中文医学实体跨度内不同元素的重要程度进行实体的融合表示。通过序列标注方法检测字符的位置标签,利用字符的位置信息指导候选实体生成,并进行实体语义分类。模型在CMeEE和CCKS2018数据集以及中文糖尿病科研文献数据集上分别进行扁平实体、嵌套实体和不连续性长实体的识别实验。实验结果表明,该方法能够有效地识别中文医学文本中不同结构的实体。 展开更多
关键词 中文医学命名实体 位置标签嵌入 结合元素重要程度的实体融合表示 级联识别 线性结构
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基于改进分数阶滑模控制的PMLSM直接推力控制
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作者 李国洪 钱凌志 《计算机应用与软件》 北大核心 2024年第3期75-80,共6页
针对分数阶滑模控制在永磁直线同步电机(Permanent Magnet Linear Synchronous Motor, PMLSM)直接推力控制下转速环精度不高、磁链和推力波动大等问题,提出一种改进的分数阶滑模控制算法,即分数阶双幂次指数趋近律、分数阶变速趋近律相... 针对分数阶滑模控制在永磁直线同步电机(Permanent Magnet Linear Synchronous Motor, PMLSM)直接推力控制下转速环精度不高、磁链和推力波动大等问题,提出一种改进的分数阶滑模控制算法,即分数阶双幂次指数趋近律、分数阶变速趋近律相结合的组合趋近律,能有效减弱滑模控制引起的系统振荡,加快趋近速率。仿真结果表明:与分数阶滑模控制相比,在PMLSM直接推力控制系统中采取改进分数阶滑模控制,磁链和推力波动明显减弱,系统响应速度加快,提高了PMLSM推力响应的抗干扰能力。 展开更多
关键词 永磁直线同步电机 分数阶滑模控制 组合趋近律 直接推力控制
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