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基于GM(1,1)-IPSO-BP的重载铁路小半径曲线钢轨磨耗预测方法
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作者 张斌 高玉祥 +2 位作者 陈再刚 王开云 时瑾 《哈尔滨工业大学学报》 EI CAS CSCD 北大核心 2024年第11期115-122,131,共9页
为实现重载铁路小半径曲线段钢轨磨耗量的精准预测,提出一种非等间距灰色模型GM(1,1)与改进粒子群算法(IPSO)优化BP神经网络相结合的钢轨磨耗预测方法。首先,根据积分原理优化GM(1,1)非等间距模型的背景值计算方法,基于改进的模型得到... 为实现重载铁路小半径曲线段钢轨磨耗量的精准预测,提出一种非等间距灰色模型GM(1,1)与改进粒子群算法(IPSO)优化BP神经网络相结合的钢轨磨耗预测方法。首先,根据积分原理优化GM(1,1)非等间距模型的背景值计算方法,基于改进的模型得到实测磨耗序列的初步预测结果;然后,利用IPSO算法对BP神经网络的权值和阈值进行自动寻优,对GM(1,1)模型初步预测序列的残差进行校正;最后,将优化后的两种模型组合构建基于GM(1,1)-IPSO-BP的重载铁路小半径曲线地段钢轨磨耗量预测模型。以某重载铁路桥上半径400 m曲线为例,利用长期的磨耗监测数据进行方法的适用性分析,研究结果表明:GM(1,1)-IPSO-BP模型克服了磨耗数据的非线性、随机性特征对计算结果的影响,预测精度优于单独使用GM(1,1)、IPSO-BP模型;背景值优化后的GM(1,1)模型预测准确性更可靠;IPSO优化算法提高了BP神经网络计算的精度和速度;预测结果和实测数据之间的相对误差不大于4%;在预测区间上的绝对误差小于0.4 mm,运用该方法能够较准确地得到钢轨磨耗的发展规律。研究结果可为重载铁路小半径曲线钢轨的精准维修和科学使用提供参考。 展开更多
关键词 钢轨磨耗 gm(1 1)模型 小半径曲线 BP神经网络 重载铁路 粒子群算法
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Study on the Prediction of Rice Blast Based on the Unbiased GM (1,1) Model 被引量:1
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作者 魏代俊 曾艳敏 邹迎春 《Plant Diseases and Pests》 CAS 2010年第6期4-6,共3页
To create a new prediction model, the unbiased GM (1,1) model is optimized by the five-point slide method in this paper. Then, based on the occurrence areas of dce blast in Enshi District during 1995 -2004, the new ... To create a new prediction model, the unbiased GM (1,1) model is optimized by the five-point slide method in this paper. Then, based on the occurrence areas of dce blast in Enshi District during 1995 -2004, the new model and unbiased GM (1, 1 ) model are applied to predict the occurrence areas of rice blast during 2005 -2010. Predicting outcomes show that the prediction accuracy of five-point unbiased sliding optimized GM (1, 1 ) model is higher than the unbiased GM (1,1) model. Finally, combined with the prediction results, the author provides some suggestion for Enshi District in the prevention and control of rice blast in 2010. 展开更多
关键词 Unbiased gm 1 1 model Five-point slide method Optimization PREDiCTiON Rice blast
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改进GM(1,1)-ARIMA-LR模型天然气产量预测研究 被引量:1
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作者 林文辉 杜彦炜 赵鹏 《西安工业大学学报》 CAS 2024年第1期32-40,共9页
为提高天然气产量在少样本情形下预测的准确性,基于对过去的预测误差进行学习的思想,加入自适应学习因子和组合学习因子以改进模型,构建包含GM(1,1)、ARIMA和LR的集成预测模型。该模型以平均误差百分比为评价指标,依据预测步长变化和过... 为提高天然气产量在少样本情形下预测的准确性,基于对过去的预测误差进行学习的思想,加入自适应学习因子和组合学习因子以改进模型,构建包含GM(1,1)、ARIMA和LR的集成预测模型。该模型以平均误差百分比为评价指标,依据预测步长变化和过去预测误差对单个模型分别进行动态调整,再建立目标规划模型对各模型进行动态加权。实证结果表明,改进GM(1,1)-ARIMA-LR模型能够更好地提取时间序列的长短时依赖关系,与其它的主流模型相比,其预测精度更高。对近5年的天然气产量进行一步、五步与八步预测,GM(1,1)-ARIMA-LR集成模型预测误差分别为1.187%、3.129%、9.855%。本文运用该模型对2023-2030年中国天然气产量进行预测。 展开更多
关键词 天然气产量 ARiMA模型 灰色gm(1 1)模型 线性回归 多步预测
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Exploiting fly models to investigate rare human neurological disorders
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作者 Tomomi Tanaka Hyung-Lok Chung 《Neural Regeneration Research》 SCIE CAS 2025年第1期21-28,共8页
Rare neurological diseases,while individually are rare,collectively impact millions globally,leading to diverse and often severe neurological symptoms.Often attributed to genetic mutations that disrupt protein functio... Rare neurological diseases,while individually are rare,collectively impact millions globally,leading to diverse and often severe neurological symptoms.Often attributed to genetic mutations that disrupt protein function or structure,understanding their genetic basis is crucial for accurate diagnosis and targeted therapies.To investigate the underlying pathogenesis of these conditions,researchers often use non-mammalian model organisms,such as Drosophila(fruit flies),which is valued for their genetic manipulability,cost-efficiency,and preservation of genes and biological functions across evolutionary time.Genetic tools available in Drosophila,including CRISPR-Cas9,offer a means to manipulate gene expression,allowing for a deep exploration of the genetic underpinnings of rare neurological diseases.Drosophila boasts a versatile genetic toolkit,rapid generation turnover,and ease of large-scale experimentation,making it an invaluable resource for identifying potential drug candidates.Researchers can expose flies carrying disease-associated mutations to various compounds,rapidly pinpointing promising therapeutic agents for further investigation in mammalian models and,ultimately,clinical trials.In this comprehensive review,we explore rare neurological diseases where fly research has significantly contributed to our understanding of their genetic basis,pathophysiology,and potential therapeutic implications.We discuss rare diseases associated with both neuron-expressed and glial-expressed genes.Specific cases include mutations in CDK19 resulting in epilepsy and developmental delay,mutations in TIAM1 leading to a neurodevelopmental disorder with seizures and language delay,and mutations in IRF2BPL causing seizures,a neurodevelopmental disorder with regression,loss of speech,and abnormal movements.And we explore mutations in EMC1 related to cerebellar atrophy,visual impairment,psychomotor retardation,and gain-of-function mutations in ACOX1 causing Mitchell syndrome.Loss-of-function mutations in ACOX1 result in ACOX1 deficiency,characterized by very-long-chain fatty acid accumulation and glial degeneration.Notably,this review highlights how modeling these diseases in Drosophila has provided valuable insights into their pathophysiology,offering a platform for the rapid identification of potential therapeutic interventions.Rare neurological diseases involve a wide range of expression systems,and sometimes common phenotypes can be found among different genes that cause abnormalities in neurons or glia.Furthermore,mutations within the same gene may result in varying functional outcomes,such as complete loss of function,partial loss of function,or gain-of-function mutations.The phenotypes observed in patients can differ significantly,underscoring the complexity of these conditions.In conclusion,Drosophila represents an indispensable and cost-effective tool for investigating rare neurological diseases.By facilitating the modeling of these conditions,Drosophila contributes to a deeper understanding of their genetic basis,pathophysiology,and potential therapies.This approach accelerates the discovery of promising drug candidates,ultimately benefiting patients affected by these complex and understudied diseases. 展开更多
关键词 ACOX1 Drosophila melanogaster GLiA lipid metabolism model organisms NEUROiNFLAMMATiON neurologic disorders NEURON rare disease VLCFA
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基于DPSIR和GM(1,1)模型的土地生态安全评价与预测——以河南省洛阳市为例
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作者 张瑶 李帅 王鹏飞 《湖北农业科学》 2024年第2期162-169,共8页
为探究洛阳市土地生态安全现状及主要影响因子,基于DPSIR模型,选取24个评价指标,构建评价指标体系。运用熵权法、障碍度模型(ODM)和灰色系统GM(1,1)模型对2010—2020年洛阳市土地生态安全状况进行评价与预测。结果表明,2010—2020年洛... 为探究洛阳市土地生态安全现状及主要影响因子,基于DPSIR模型,选取24个评价指标,构建评价指标体系。运用熵权法、障碍度模型(ODM)和灰色系统GM(1,1)模型对2010—2020年洛阳市土地生态安全状况进行评价与预测。结果表明,2010—2020年洛阳市土地生态安全呈上升趋势,2010—2017年波动幅度较小,2018年土地生态安全指数大幅增加,从0.4805增加至0.6027;2020年土地生态安全等级从临界安全等级上升至较安全等级,其中人口自然增长率、单位耕地农药消耗、人均公园绿地面积、第三产业产值比重等指标因素是指数上涨的重要动力;权重最大的子系统为响应子系统,权重最大的单一指标为人均公园绿地面积;障碍因素中出现频次最高的指标为生活垃圾无害化处理率;从灰色系统GM(1,1)模型的预测结果来看,洛阳市土地生态安全等级将在2023年达到安全等级。 展开更多
关键词 土地生态安全指数 DPSiR模型 灰色系统gm(1 1)模型 障碍度模型(ODM) 河南省洛阳市
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Establishment of a humanized ST6GAL1 mouse model for influenza research
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作者 Lyu Chao Han Feng +10 位作者 Gao Qian Lv Limin Lu Ziwei Lu Shuangshuang Li Xiaoyan Hu Yuechao Yang Mengjie Zhao Yingze Liu Jun Lu Xuancheng Duo Shuguang 《Animal Models and Experimental Medicine》 CAS CSCD 2024年第3期337-346,共10页
Background:This study aimed to construct and characterize a humanized influenza mouse model expressing hST6GAL1.Methods:Humanized fragments,consisting of the endothelial cell-specific K18 promoter,human ST6GAL1-encodi... Background:This study aimed to construct and characterize a humanized influenza mouse model expressing hST6GAL1.Methods:Humanized fragments,consisting of the endothelial cell-specific K18 promoter,human ST6GAL1-encoding gene,and luciferase gene,were microinjected into the fertilized eggs of mice.The manipulated embryos were transferred into the oviducts of pseudopregnant female mice.The offspring were identified using PCR.Mice exhibiting elevated expression of the hST6GAL1 gene were selectively bred for propagation,and in vivo analysis was performed for screening.Expression of the humanized gene was tested by performing immunohistochemical(IHC)analysis.Hematologic and biochemical analyses using the whole blood and serum of humanized hST6GAL1 mice were performed.Results:Successful integration of the human ST6GAL1 gene into the mouse genome led to the overexpression of human SiaT ST6GAL1.Seven mice were identified as carrying copies of the humanized gene,and the in vivo analysis indicated that hST6GAL1gene expression in positive mice mirrored influenza virus infection characteristics.The IHC results revealed that hST6GAL1 was expressed in the lungs of humanized mice.Moreover,the hematologic and biochemical parameters of the positive mice were within the normal range.Conclusion:A humanized influenza mouse model expressing the hST6GAL1 gene was successfully established and characterized. 展开更多
关键词 hST6GAL1 humanized mice influenza animal model
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GM1通过PI3K/AKT/GSK3β信号通路减轻脑出血小鼠的神经功能损伤 被引量:1
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作者 翁红林 张崇太 吴俊 《中国老年学杂志》 CAS 北大核心 2024年第1期188-192,共5页
目的研究单唾液酸四己糖基神经节苷脂(GM1)对急性脑出血小鼠的神经功能保护作用及其机制。方法构建小鼠脑出血神经损伤模型。将小鼠随机分为假手术(Sham)组、模型(Model)组、GM1(25 mg/(kg·d))组、GM1+LY294002(6μg/(kg·d))... 目的研究单唾液酸四己糖基神经节苷脂(GM1)对急性脑出血小鼠的神经功能保护作用及其机制。方法构建小鼠脑出血神经损伤模型。将小鼠随机分为假手术(Sham)组、模型(Model)组、GM1(25 mg/(kg·d))组、GM1+LY294002(6μg/(kg·d))组各10只。于造模结束1 h后腹腔注射GM1或LY294002,连续1 w,Sham组和Model组腹腔注射等量生理盐水。采用神经功能缺损评分、脑含水量等检测各组神经功能损伤;苏木素-伊红(HE)染色试剂盒和尼氏染色试剂盒检测各组脑组织和神经元损伤水平;酶联试验免疫吸附试验(ELISA)法测定血清炎性因子白细胞介素(IL)-6、IL-1β及肿瘤坏死因子(TNF)-α水平;Western印迹检测B细胞淋巴瘤(Bcl)-2、Bcl-2相关X蛋白(Bax)、裂解的胱天蛋白酶(cleaved caspase)-3、磷脂酰肌醇-3激酶/蛋白激酶B/糖原合成酶激酶(PI3K/AKT/GSK)3β蛋白表达。结果与Sham组相比,Model组神经功能损伤严重(P<0.05),且神经细胞出现大量凋亡。Western印迹结果显示,Bcl-2、p-PI3K/PI3K、p-AKT/AKT蛋白表达明显下调,Bax、cleaved caspase-3、p-GSK3β/GSK3β蛋白表达明显上调(P<0.05);与Model组相比,GM1治疗组神经功能损伤明显减轻,脑组织损伤和炎症明显减轻且神经细胞凋亡明显被抑制(P<0.05),而GM+LY294002使得这一治疗作用明显被弱化(P<0.05)。结论GM1能有效保护急性脑出血小鼠的神经功能,其作用机制可能与PI3K/AKT/GSK3β信号通路有关。 展开更多
关键词 单唾液酸四己糖基神经节苷脂(gm1) 急性脑出血 神经损伤 磷脂酰肌醇-3激酶/蛋白激酶B/糖原合成酶激酶(Pi3K/AKT/GSK)3β
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Estimation of evapotranspiration from artificial forest in mountainous areas of western Loess Plateau based on HYDRUS-1D model
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作者 LU Rui ZHANG Mingjun +4 位作者 ZHANG Yu QIANG Yuquan CHE Cunwei SUN Meiling WANG Shengjie 《Journal of Arid Land》 SCIE CSCD 2024年第12期1664-1685,共22页
Evapotranspiration is the most important expenditure item in the water balance of terrestrial ecosystems,and accurate evapotranspiration modeling is of great significance for hydrological,ecological,agricultural,and w... Evapotranspiration is the most important expenditure item in the water balance of terrestrial ecosystems,and accurate evapotranspiration modeling is of great significance for hydrological,ecological,agricultural,and water resource management.Artificial forests are an important means of vegetation restoration in the western Loess Plateau,and accurate estimates of their evapotranspiration are essential to the management and development of water use strategies for artificial forests.This study estimated the soil moisture and evapotranspiration based on the HYDRUS-1D model for the artificial Platycladus orientalis(L.)Franco forest in western mountains of Loess Plateau,China from 20 April to 31 October,2023.Moreover,the influence factors were identified by combining the correlation coefficient method and the principal component analysis(PCA)method.The results showed that HYDRUS-1D model had strong applicability in portraying hydrological processes in this area and revealed soil water surplus from 20 April to 31 October,2023.The soil water accumulation was 49.64 mm;the potential evapotranspiration(ET_(p))was 809.67 mm,which was divided into potential evaporation(E_(p);95.07 mm)and potential transpiration(T_(p);714.60 mm);and the actual evapotranspiration(ET_(a))was 580.27 mm,which was divided into actual evaporation(E_(a);68.27 mm)and actual transpiration(T_(a);512.00 mm).From April to October 2023,the ET_(p),E_(p),T_(p),ET_(a),E_(a),and T_(a) first increased and then decreased on both monthly and daily scales,exhibiting a single-peak type trend.The average ratio of T_(a)/ET_(a) was 0.88,signifying that evapotranspiration mainly stemmed from transpiration in this area.The ratio of ET_(a)/ET_(p) was 0.72,indicating that this artificial forest suffered from obvious drought stress.The ET_(p) was significantly positively correlated with ET_(a),and the R^(2) values on the monthly and daily scales were 0.9696 and 0.9635(P<0.05),respectively.Furthermore,ET_(a) was significantly positively correlated with temperature,solar radiation,and wind speed,and negatively correlated with relative humidity and precipitation(P<0.05);and temperature exhibited the highest correlation with ET_(a).Thus,ET_(p) and temperature were the decisive contributors to ET_(a) in this area.The findings provide an effective method for simulating regional evapotranspiration and theoretical reference for water management of artificial forests,and deepen understanding of effects of each influence factors on ET_(a) in arid areas. 展开更多
关键词 potential evapotranspiration actual evapotranspiration EVAPORATiON TRANSPiRATiON HYDRUS-1D model Loess Plateau soil water content
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Tidal modeling based on satellite altimetry observations of TOPEX/ Poseidon, Jason1, Jason2, and Jason3 with high prediction capability: A case study of the Baltic Sea
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作者 Alireza A.Ardalan Asiyeh Hashemifaraz 《Geodesy and Geodynamics》 EI CSCD 2024年第4期404-418,共15页
This research aims to optimize the utilization of long-term sea level data from the TOPEX/Poseidon,Jason1,Jason2,and Jason3 altimetry missions for tidal modeling.We generate a time series of along-track observations a... This research aims to optimize the utilization of long-term sea level data from the TOPEX/Poseidon,Jason1,Jason2,and Jason3 altimetry missions for tidal modeling.We generate a time series of along-track observations and apply a developed method to produce tidal models with specific tidal constituents for each location.Our tidal modeling methodology follows an iterative process:partitioning sea surface height(SSH)observations into analysis/training and prediction/validation parts and ultimately identi-fying the set of tidal constituents that provide the best predictions at each time series location.The study focuses on developing 1256 time series along the altimetry tracks over the Baltic Sea,each with its own set of tidal constituents.Verification of the developed tidal models against the sSH observations within the prediction/validation part reveals mean absolute error(MAE)values ranging from 0.0334 m to 0.1349 m,with an average MAE of 0.089 m.The same validation process is conducted on the FES2014 and EOT20 global tidal models,demonstrating that our tidal model,referred to as BT23(short for Baltic Tide 2023),outperforms both models with an average MAE improvement of 0.0417 m and 0.0346 m,respectively.In addition to providing details on the development of the time series and the tidal modeling procedure,we offer the 1256 along-track time series and their associated tidal models as supplementary materials.We encourage the satellite altimetry community to utilize these resources for further research and applications. 展开更多
关键词 Satellitealtimetry Baltic Sea Ocean tide modeling Jason3 Jason2 Jason1 TOPEX/POSEiDON EOT20 FES2014
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Modeling mechanism and extension of GM (1,1) 被引量:16
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作者 Xinping Xiao Yichen Hu Huan Guo 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2013年第3期445-453,共9页
Firstly, the research progress of grey model GM (1,1) is summarized, which is divided into three development stages: assimilation, alienation and melting stages. Then, the matrix analysis theory is used to study th... Firstly, the research progress of grey model GM (1,1) is summarized, which is divided into three development stages: assimilation, alienation and melting stages. Then, the matrix analysis theory is used to study the modeling mechanism of GM (1,1), which decomposes the modeling data matrix into raw data transformation matrix, accumulated generating operation matrix and background value selection matrix. The changes of these three matrices are the essential reasons affecting the modeling and the accuracy of GM (1,1). Finally, the paper proposes a generalization grey model GGM (1,1), which is a extended form of GM (1,1) and also a unified form of model GM (1,1), model GM (1,1,α), stage grey model, hopping grey model, generalized accumulated model, strengthening operator model, weakening operator model and unequal interval model. And the theory and practical significance of the extended model is analyzed. 展开更多
关键词 gm 1 1 matrix analysis Ggm 1 1 model parameter modeling mechanism.
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An approach to estimate tree height using PolInSAR data constructed by the Sentinel-1 dual-pol SAR data and RVoG model
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作者 Yin Zhang Ding-Feng Duan 《Journal of Electronic Science and Technology》 EI CAS CSCD 2024年第3期69-79,共11页
We estimate tree heights using polarimetric interferometric synthetic aperture radar(PolInSAR)data constructed by the dual-polarization(dual-pol)SAR data and random volume over the ground(RVoG)model.Considering the Se... We estimate tree heights using polarimetric interferometric synthetic aperture radar(PolInSAR)data constructed by the dual-polarization(dual-pol)SAR data and random volume over the ground(RVoG)model.Considering the Sentinel-1 SAR dual-pol(SVV,vertically transmitted and vertically received and SVH,vertically transmitted and horizontally received)configuration,one notes that S_(HH),the horizontally transmitted and horizontally received scattering element,is unavailable.The S_(HH)data were constructed using the SVH data,and polarimetric SAR(PolSAR)data were obtained.The proposed approach was first verified in simulation with satisfactory results.It was next applied to construct PolInSAR data by a pair of dual-pol Sentinel-1A data at Duke Forest,North Carolina,USA.According to local observations and forest descriptions,the range of estimated tree heights was overall reasonable.Comparing the heights with the ICESat-2 tree heights at 23 sampling locations,relative errors of 5 points were within±30%.Errors of 8 points ranged from 30%to 40%,but errors of the remaining 10 points were>40%.The results should be encouraged as error reduction is possible.For instance,the construction of PolSAR data should not be limited to using SVH,and a combination of SVH and SVV should be explored.Also,an ensemble of tree heights derived from multiple PolInSAR data can be considered since tree heights do not vary much with time frame in months or one season. 展开更多
关键词 Constructed polarimetric SAR data Dual polarization Sentinel-1 SAR data Polarimetric interferometric SAR Random volume over the ground model Tree height estimation
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Numerical Models and Methods of Atmospheric Parameters Originating in the Formation of the Earth’s Climatic Cycle
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作者 Wend Dolean Arsène Ilboudo Kassoum Yamba +1 位作者 Windé Nongué Daniel Koumbem Issaka Ouédraogo 《Atmospheric and Climate Sciences》 2024年第2期277-286,共10页
Atmospheric models are physical equations based on the ideal gas law. Applied to the atmosphere, this law yields equations for water, vapor (gas), ice, air, humidity, dryness, fire, and heat, thus defining the model o... Atmospheric models are physical equations based on the ideal gas law. Applied to the atmosphere, this law yields equations for water, vapor (gas), ice, air, humidity, dryness, fire, and heat, thus defining the model of key atmospheric parameters. The distribution of these parameters across the entire planet Earth is the origin of the formation of the climatic cycle, which is a normal climatic variation. To do this, the Earth is divided into eight (8) parts according to the number of key parameters to be defined in a physical representation of the model. Following this distribution, numerical models calculate the constants for the formation of water, vapor, ice, dryness, thermal energy (fire), heat, air, and humidity. These models vary in complexity depending on the indirect trigonometric direction and simplicity in the sum of neighboring models. Note that the constants obtained from the equations yield 275.156˚K (2.006˚C) for water, 273.1596˚K (0.00963˚C) for vapor, 273.1633˚K (0.0133˚C) for ice, 0.00365 in/s for atmospheric dryness, 1.996 in<sup>2</sup>/s for humidity, 2.993 in<sup>2</sup>/s for air, 1 J for thermal energy of fire, and 0.9963 J for heat. In summary, this study aims to define the main parameters and natural phenomena contributing to the modification of planetary climate. . 展开更多
关键词 Atmospheric Parameter 1 Climatic Cycle 2 Numerical models 3
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A New Modified GM (1,1) Model: Grey Optimization Model 被引量:12
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作者 Xiao Xinping College of Scienced, Wuhan University of Technologyl 430063, P R. China Deng Julong Dept. of Control, Huazhong University of Science and Technology, Wuhan 430074,P. R. China 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2001年第2期1-5,共5页
Based on the optimization method, a new modified GM (1,1) model is presented, which is characterized by more accuracy prediction for the grey modeling.
关键词 gm (1 1) Grey optimization model Optimization method.
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Application of Modelica Based Multi- Domain Modeling and Simulation for Gravity-1
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作者 ZHANG Chi BU Xiangwei +3 位作者 XU Lijie WU Kao HOU Shiyuan XU Guoguang 《Aerospace China》 2024年第1期47-55,共9页
In the R&D phase of Gravity-1(YL-1), a multi-domain modeling and simulation technology based on Modelica language was introduced, which was a recent attempt in the practice of modeling and simulation method for la... In the R&D phase of Gravity-1(YL-1), a multi-domain modeling and simulation technology based on Modelica language was introduced, which was a recent attempt in the practice of modeling and simulation method for launch vehicles in China. It realizes a complex coupling model within a unified model for different domains, so that technologists can work on one model. It ensured the success of YL-1 first launch mission, supports rapid iteration, full validation, and tight design collaboration. 展开更多
关键词 modeliCA Gravity-1 simulation modeling launch vehicle model
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Prediction of efficient outputs based on GM(1,N) model and weak DEA efficiency 被引量:2
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作者 Jiefang Wang Sifeng Liu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2011年第6期933-939,共7页
This paper expresses the efficient outputs of decisionmaking unit(DMU) as the sum of "average outputs" forecasted by a GM(1,N) model and "increased outputs" which reflect the difficulty to realize efficient ou... This paper expresses the efficient outputs of decisionmaking unit(DMU) as the sum of "average outputs" forecasted by a GM(1,N) model and "increased outputs" which reflect the difficulty to realize efficient outputs.The increased outputs are solved by linear programming using data envelopment analysis efficiency theories,wherein a new sample is introduced whose inputs are equal to the budget in the issue No.n + 1 and outputs are forecasted by the GM(1,N) model.The shortcoming in the existing methods that the forecasted efficient outputs may be less than the possible actual outputs according to developing trends of input-output rate in the periods of pre-n is overcome.The new prediction method provides decision-makers with more decisionmaking information,and the initial conditions are easy to be given. 展开更多
关键词 efficient outputs gm1 N) model data envelopment analysis(DEA) weak DEA efficiency prediction.
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Prediction model of interval grey number based on DGM(1,1) 被引量:19
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作者 Bo Zeng Sifeng Liu Naiming Xie 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第4期598-603,共6页
In grey system theory,the studies in the field of grey prediction model are focused on real number sequences,rather than grey number ones.Hereby,a prediction model based on interval grey number sequences is proposed.B... In grey system theory,the studies in the field of grey prediction model are focused on real number sequences,rather than grey number ones.Hereby,a prediction model based on interval grey number sequences is proposed.By mining the geometric features of interval grey number sequences on a two-dimensional surface,all the interval grey numbers are converted into real numbers by means of certain algorithm,and then the prediction model is established based on those real number sequences.The entire process avoids the algebraic operations of grey number,and the prediction problem of interval grey number is usefully solved.Ultimately,through an example's program simulation,the validity and practicability of this novel model are verified. 展开更多
关键词 grey system theory prediction model interval grey number grey number band grey number layer Dgm1 1 model.
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Improvement and application of GM(1,1) model based on multivariable dynamic optimization 被引量:14
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作者 WANG Yuhong LU Jie 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2020年第3期593-601,共9页
For the classical GM(1,1)model,the prediction accuracy is not high,and the optimization of the initial and background values is one-sided.In this paper,the Lagrange mean value theorem is used to construct the backgrou... For the classical GM(1,1)model,the prediction accuracy is not high,and the optimization of the initial and background values is one-sided.In this paper,the Lagrange mean value theorem is used to construct the background value as a variable related to k.At the same time,the initial value is set as a variable,and the corresponding optimal parameter and the time response formula are determined according to the minimum value of mean relative error(MRE).Combined with the domestic natural gas annual consumption data,the classical model and the improved GM(1,1)model are applied to the calculation and error comparison respectively.It proves that the improved model is better than any other models. 展开更多
关键词 grey prediction gm(1 1)model background value grey system theory
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Dynamic GM(1,1) Model Based on Cubic Spline for Electricity Consumption Prediction in Smart Grid 被引量:10
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作者 WANG Xiaojia YANG Shanlin DING Jing WANG Haijiang 《China Communications》 SCIE CSCD 2010年第4期83-88,共6页
Electricity demand forecasting plays an important role in smart grid expansion planning.In this paper,we present a dynamic GM(1,1) model based on grey system theory and cubic spline function interpolation principle.Us... Electricity demand forecasting plays an important role in smart grid expansion planning.In this paper,we present a dynamic GM(1,1) model based on grey system theory and cubic spline function interpolation principle.Using piecewise polynomial interpolation thought,this model can dynamically predict the general trend of time series data.Combined with low-order polynomial,the cubic spline interpolation has smaller error,avoids the Runge phenomenon of high-order polynomial,and has better approximation effect.Meanwhile,prediction is implemented with the newest information according to the rolling and feedback mechanism and fluctuating error is controlled well to improve prediction accuracy in time-varying environment.Case study using the living electricity consumption data of Jiangsu province in 2008 is presented to demonstrate the effectiveness of the proposed model. 展开更多
关键词 Smart Grid gm1 1 model Cubic Spline Rolling Strategy Electricity Consumption Prediction
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Application of Renewal Gray GM (1,1) Model to Prediction of Landslide Deformation 被引量:1
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作者 Zhaoyang Wang 《Journal of Geoscience and Environment Protection》 2017年第9期148-154,共7页
The gray renewal GM (1,1) landslide prediction model was established by improving the gray model. Based on the established model, the author has made prediction of landslide deformation to the Xiangjiapo landslide and... The gray renewal GM (1,1) landslide prediction model was established by improving the gray model. Based on the established model, the author has made prediction of landslide deformation to the Xiangjiapo landslide and the Lianziya dangerous rock body. The results show that the gray renewal GM (1,1) model can supplement the new information in time and remove the old information which reduces the meaning of the information because of time lapse. Therefore, the model is closer to reality. 展开更多
关键词 LANDSLiDE RENEWAL GRAY gm (1 1) model GRAY System THEORY
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Application of non-equal interval GM(1,1)model in oil monitoring of internal combustion engine 被引量:2
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作者 陈士玮 李柱国 周守西 《Journal of Central South University of Technology》 EI 2005年第6期705-708,共4页
The basic difference non-equal interval model GM(1,1) in grey theory was used to fit and forecast data series with non-equal lengths and different inertias, acquired from oil monitoring of internal combustion engines.... The basic difference non-equal interval model GM(1,1) in grey theory was used to fit and forecast data series with non-equal lengths and different inertias, acquired from oil monitoring of internal combustion engines. The fitted and forecasted results show that the length or inertia of a sequence affects its precision very much, i.e. the bigger the inertia of a sequence is, or the shorter the length of a series is, the less the errors of fitted and forecasted results are. Based on the research results, it is suggested that short series should be applied to be fitted and forecasted; for longer series, the newer datum should be applied instead of the older datum to be analyzed by non- equalinterval GM(1,1) to improve the forecasted and fitted precision, and that data sequence should be verified to satisfy the conditions of grey forecasting. 展开更多
关键词 gm1 1 model oil monitoring spectrometric analysis internal combustion engine
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