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Dimension by Dimension Finite Volume HWENO Method for Hyperbolic Conservation Laws
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作者 Feng Zheng Jianxian Qiu 《Communications on Applied Mathematics and Computation》 EI 2024年第1期605-624,共20页
In this paper,we propose a finite volume Hermite weighted essentially non-oscillatory(HWENO)method based on the dimension by dimension framework to solve hyperbolic conservation laws.It can maintain the high accuracy ... In this paper,we propose a finite volume Hermite weighted essentially non-oscillatory(HWENO)method based on the dimension by dimension framework to solve hyperbolic conservation laws.It can maintain the high accuracy in the smooth region and obtain the high resolution solution when the discontinuity appears,and it is compact which will be good for giving the numerical boundary conditions.Furthermore,it avoids complicated least square procedure when we implement the genuine two dimensional(2D)finite volume HWENO reconstruction,and it can be regarded as a generalization of the one dimensional(1D)HWENO method.Extensive numerical tests are performed to verify the high resolution and high accuracy of the scheme. 展开更多
关键词 Finite volume dimension by dimension HWENO Hyperbolic conservation laws
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Scalable Temporal Dimension Preserved Tensor Completion for Missing Traffic Data Imputation With Orthogonal Initialization
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作者 Hong Chen Mingwei Lin +1 位作者 Jiaqi Liu Zeshui Xu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第10期2188-2190,共3页
Dear Editor,This letter puts forward a novel scalable temporal dimension preserved tensor completion model based on orthogonal initialization for missing traffic data(MTD)imputation.The MTD imputation acts directly on... Dear Editor,This letter puts forward a novel scalable temporal dimension preserved tensor completion model based on orthogonal initialization for missing traffic data(MTD)imputation.The MTD imputation acts directly on accessing the traffic state,and affects the traffic management. 展开更多
关键词 dimension management traffic
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A novel box-counting method for quantitative fractal analysis of threedimensional pore characteristics in sandstone
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作者 Huiqing Liu Heping Xie +2 位作者 Fei Wu Cunbao Li Renbo Gao 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第4期479-489,共11页
Fractal theory offers a powerful tool for the precise description and quantification of the complex pore structures in reservoir rocks,crucial for understanding the storage and migration characteristics of media withi... Fractal theory offers a powerful tool for the precise description and quantification of the complex pore structures in reservoir rocks,crucial for understanding the storage and migration characteristics of media within these rocks.Faced with the challenge of calculating the three-dimensional fractal dimensions of rock porosity,this study proposes an innovative computational process that directly calculates the three-dimensional fractal dimensions from a geometric perspective.By employing a composite denoising approach that integrates Fourier transform(FT)and wavelet transform(WT),coupled with multimodal pore extraction techniques such as threshold segmentation,top-hat transformation,and membrane enhancement,we successfully crafted accurate digital rock models.The improved box-counting method was then applied to analyze the voxel data of these digital rocks,accurately calculating the fractal dimensions of the rock pore distribution.Further numerical simulations of permeability experiments were conducted to explore the physical correlations between the rock pore fractal dimensions,porosity,and absolute permeability.The results reveal that rocks with higher fractal dimensions exhibit more complex pore connectivity pathways and a wider,more uneven pore distribution,suggesting that the ideal rock samples should possess lower fractal dimensions and higher effective porosity rates to achieve optimal fluid transmission properties.The methodology and conclusions of this study provide new tools and insights for the quantitative analysis of complex pores in rocks and contribute to the exploration of the fractal transport properties of media within rocks. 展开更多
关键词 3D fractal analysis Fractal dimension Rock pore structure Box-counting method Permeability simulation Computational geosciences
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The Global Attractor and Its Dimension Estimation of Generalized Kolmogorov-Petrovlkii-Piskunov Equation
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作者 Yuhuai Liao 《Journal of Applied Mathematics and Physics》 2024年第4期1178-1187,共10页
In this paper, the initial boundary value problem of a class of nonlinear generalized Kolmogorov-Petrovlkii-Piskunov equations is studied. The existence and uniqueness of the solution and the bounded absorption set ar... In this paper, the initial boundary value problem of a class of nonlinear generalized Kolmogorov-Petrovlkii-Piskunov equations is studied. The existence and uniqueness of the solution and the bounded absorption set are proved by the prior estimation and the Galerkin finite element method, thus the existence of the global attractor is proved and the upper bound estimate of the global attractor is obtained. 展开更多
关键词 Generalized Kolmogorov-Petrovlkii-Piskunov Equation Existence of Solution Hausdorff dimension Fractal dimension
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A Study of the Teaching Effects of Case Analysis in Cross-Cultural Communication Class-Taking Individualism-Collectivism Cultural Dimension Class as an Example
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作者 ZHOU Qingyan 《Sino-US English Teaching》 2024年第8期372-376,共5页
This study introduces the individualism-collectivism dimension of the cultural dimension of cross-cultural communication initiated by Geert Hofstede.Different cultures must develop a way of correlating that strikes a ... This study introduces the individualism-collectivism dimension of the cultural dimension of cross-cultural communication initiated by Geert Hofstede.Different cultures must develop a way of correlating that strikes a balance between caring for themselves and showing concern for others.Individualist culture encourages uniqueness and independence while collectivist culture emphasizes conformity and mutual assistance.This article introduces how to use case analysis method to effectively carry out classroom teaching in this cultural dimension. 展开更多
关键词 cultural dimension case analysis cross cultural communication teaching effects
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Rectangular tunnel heading stability in three dimensions and its predictive machine learning models
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作者 Jim Shiau Suraparb Keawsawasvong +3 位作者 Van Qui Lai Thanachon Promwichai Viroon Kamchoom Rungkhun Banyong 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第11期4683-4696,共14页
Tunnel heading stability in two dimensions(2D)has been extensively investigated by numerous scholars in the past decade.One significant limitation of 2D analysis is the absence of actual tunnel geometry modeling with ... Tunnel heading stability in two dimensions(2D)has been extensively investigated by numerous scholars in the past decade.One significant limitation of 2D analysis is the absence of actual tunnel geometry modeling with a considerable degree of idealization.Nevertheless,it is possible to study the stability of tunnels in three dimensions(3D)with a rectangular shape using finite element limit analysis(FELA)and a nonlinear programming technique.This paper employs 3D FELA to generate rigorous solutions for stability numbers,failure mechanisms,and safety factors for rectangular-shaped tunnels.To further explore the usefulness of the produced results,multivariate adaptive regression spline(MARS)is used for machine learning of big dataset and development of design equations for practical design applications.The study should be of great benefit to tunnel design practices using the developed equations provided in the paper. 展开更多
关键词 Wide rectangular tunnel Finite element limit analysis(FELA) Multivariate adaptive regression spline(MARS) Three dimensions(3D) Stability analysis
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Ca_v3.3-mediated endochondral ossification in a three-dimensional bioprinted Gel MA hydrogel
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作者 Zhi Wang Xin Wang +6 位作者 Yang Huang Junjun Yang Zu Wan Zhenlan Fu Xiaoyuan Gong Guangxing Chen Liu Yang 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2024年第6期983-999,共17页
The growth plate(GP)is a crucial tissue involved in skeleton development via endochondral ossification(EO).The bone organoid is a potential research model capable of simulating the physiological function,spatial struc... The growth plate(GP)is a crucial tissue involved in skeleton development via endochondral ossification(EO).The bone organoid is a potential research model capable of simulating the physiological function,spatial structure,and intercellular communication of native GPs.However,mimicking the EO process remains a key challenge for bone organoid research.To simulate this orderly mineralization process,we designed an in vitro sh Ca_(v)3.3 ATDC5-loaded gelatin methacryloyl(Gel MA)hydrogel model and evaluated its bioprintability for future organoid construction.In this paper,we report the first demonstration that the T-type voltage-dependent calcium channel(T-VDCC)subtype Ca_(v)3.3 is dominantly expressed in chondrocytes and is negatively correlated with the hypertrophic differentiation of chondrocytes during the EO process.Furthermore,Ca_(v)3.3 knockdown chondrocytes loaded with the Gel MA hydrogel successfully captured the EO process and provide a bioink capable of constructing layered and orderly mineralized GP organoids in the future.The results of this study could therefore provide a potential target for regulating the EO process and a novel strategy for simulating it in bone organoids. 展开更多
关键词 Bone organoid Endochondral ossification T-type voltage-dependent calcium channel(T-vDCC) Ca_(v)3.3 3D bioprinting
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The Historical Position and Value Dimensions of Human Rights Civilization
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作者 鲁广锦 PAN Yingzhao 《The Journal of Human Rights》 2024年第1期11-41,共31页
Human beings are the mainstay and the ultimate goal of civilization.The history of human civilization is a continuous struggle to realize the respect,liberation,protection,and development of humanity.Human rights are ... Human beings are the mainstay and the ultimate goal of civilization.The history of human civilization is a continuous struggle to realize the respect,liberation,protection,and development of humanity.Human rights are an achievement of humanity and a symbol of progress,and the human rights civilization is an important component of human civilization.Understanding and interpreting human rights from the perspective of human rights civilization means that human rights are not only a concept or an idea but also a grand historical and long-term social practice.Up to now,the development of human rights civilization has roughly experienced four awakening eras:initialization,revolution,popularization,and globalization.In terms of its value dimensions,it has the characteristics of progressiveness,diversity,commonality,inclusiveness,indivisibility,openness,and so on.The historical position of human rights civilization and the development of its value dimensions have shown to the world that human rights are the common wealth of humanity,and human rights belong to all mankind;human rights are historical,concrete,and developmental;the concept of human rights is constantly evolving,and its connotations and categories are constantly expanding;achieving the free and well-rounded development of every person is the highest value realm of human rights civilization.The Chinese modernization endows Chinese civilization with modern strength and opens up new horizons for human rights civilization.The new pattern of human rights civilization to be created by Chinese modernization not only possesses the common characteristics of human rights civilization but also enjoys Chinese characteristics based on its own national conditions,enriching and developing the diversity of human rights civilization for all mankind. 展开更多
关键词 human rights civilization four awakening eras of human rights value dimensions of human rights Chinese modernization new pattern of human rights civilization with Chinese characteristics
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Reservoir detection based on EMD and correlation dimension 被引量:3
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作者 文晓涛 贺振华 黄德济 《Applied Geophysics》 SCIE CSCD 2009年第1期70-76,103,104,共9页
In hydrocarbon reservoirs, seismic waveforms become complex and the correlation dimension becomes smaller. Seismic waves are signals with a definite frequency bandwidth and the waveform is affected by all the frequenc... In hydrocarbon reservoirs, seismic waveforms become complex and the correlation dimension becomes smaller. Seismic waves are signals with a definite frequency bandwidth and the waveform is affected by all the frequency components in the band. The results will not define the reservoir well if we calculate correlation dimension directly. In this paper, we present a method that integrates empirical mode decomposition (EMD) and correlation dimension. EMD is used to decompose the seismic waves and calculate the correlation dimension of every intrinsic mode function (IMF) component of the decomposed wave. Comparing the results with reservoirs identified by known wells, the most effective IMF is chosen and used to predict the reservoir. The method is applied in the Triassic Zhongyou group in the XX area of the Tahe oil field with quite good results. 展开更多
关键词 empirical mode decomposition correlation dimension intrinsic mode function RESERvOIR
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Mathematically modeling the main dimensions of self-elevating drilling units
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作者 王运龙 纪卓尚 林焰 《Journal of Marine Science and Application》 2009年第3期211-215,共5页
The present status of self-elevating drilling units was analysed. Based on statistics of the main dimensions of self-elevating drilling units, a mathematical model was established using stepwise return procedures and ... The present status of self-elevating drilling units was analysed. Based on statistics of the main dimensions of self-elevating drilling units, a mathematical model was established using stepwise return procedures and a back-propagation neural network. mathematical model is applicable and reliable. The of the main dimensions of self-elevating drilling Analysis of examples of calculations showed that the model is useful for mastering the essential variations units and can be used for technical and economic analysis as well as in conceptual designs of drilling units. 展开更多
关键词 self-elevating drilling unit main dimensions single variable multi-variable
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Multi-slice Spiral CT Three-dimensional Portography in Portal Vein Tumor Thrombus of Hepatic Cancer
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作者 俞同福 王德杭 +1 位作者 冯阳 张廉良 《The Chinese-German Journal of Clinical Oncology》 CAS 2003年第4期203-205,250,共4页
Objective: To study the clinical significance of multi-slice spiral CT 3-dimensional (3D) portography in portal vein tumor thrombosis of hepatocellular cacinoma.Methods: 57 cases undergoing 3D portography were collect... Objective: To study the clinical significance of multi-slice spiral CT 3-dimensional (3D) portography in portal vein tumor thrombosis of hepatocellular cacinoma.Methods: 57 cases undergoing 3D portography were collected, of which 6 cases were normal, 5 cases were subjected to cirrhosis and hypertension of portal vein, 42 cases had portal tumor thrombus of hepatic cancer, and the remaining 4 cases showed lymph node enlargment in hilar of liver. All data of the patients came from conventional multi-slice spiral CT double phase of liver. Contrast media was 1.5–2 ml/kg with the injection rate being 2.5–3 ml/s. Axis and 3D portography was analyzed and compared in 42 cases of portal tumor thrombus of hepatic cancer.Results: According to portal tumor thrombus position, 42 cases were fallen into three categories: left (13 cases), right (20 cases), main (9 cases) of potal vein. There was no difference between axis and 3D portography in displaying portal tumor thrombus of hepatic cancer (P>0.05), but 3D portography showing collateral branches was better than axis portography after main portal vein thrombus.Conclusion: Multi-slice spiral CT 3D portography can display the position and types of portal tumor thrombus of hepatic cancer. 3D combined with axis portography can better evaluate the portal tumor thrombus of hepatic cancer and guide to select the therapies. Key words portal vein - tumor thrombus - multi-slice CT - 3 dimension imaging 展开更多
关键词 portal vein tumor thrombus multi-slice CT 3 dimension imaging
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EFFECT OF TIME AND ENVIRONMENT ON THE DIMENSION PRECISION AND MASS OF LOM PROTOTYPES
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作者 张连洪 李华友 《Transactions of Tianjin University》 EI CAS 2001年第3期214-216,共3页
The effect of time and environment on the dimension precision and mass of LOM prototypes was experimentally investigated.It is to identify the stability of the dimension of LOM prototypes after forming.The results sho... The effect of time and environment on the dimension precision and mass of LOM prototypes was experimentally investigated.It is to identify the stability of the dimension of LOM prototypes after forming.The results show that the dimension and the mass tendency to grow,which is mainly caused by elastic recovery and moisture absorption and is characterized principally by the growth of Z dimension.Self restraint can be a significant factor to influence Z growth of LOM prototypes. 展开更多
关键词 laminated object manufacturing (LOM) time effect dimension stability rapid prototyping
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An Analysis on Cultural Values of Companies from China and the United States——Based on Hofstede's Cultural Dimension Theory
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作者 占小海 张若晨 《海外英语》 2015年第23期205-210,共6页
Nowadays, commercial competition is becoming fiercer and fiercer, and with the globalization proceeding, when a company tries to expand, promote and develop, it needs to adapt itself to the open business society while... Nowadays, commercial competition is becoming fiercer and fiercer, and with the globalization proceeding, when a company tries to expand, promote and develop, it needs to adapt itself to the open business society while not losing its own culture. Since English has been widely used in the world, an effective and suitable English website is essential for a company to use as a kind of advertisement and publicity, where its cultural values are presented.With companies' websites as subjects and Hofstede's cultural dimension theory as the theoretical basis, this study, through text content and data analysis of company profiles,strategies and cultures, tries to find out the tendency of Chinese and American companies on the five cultural value dimensions,which is power distance, uncertainty avoidance, individualism, masculinity and long-term orientation. Accordingly, constructive suggestions are put forward to help appease and avoid misunderstandings, and promote business communication and collaboration. 展开更多
关键词 COMPANY CULTURAL values CULTURAL dimension theory COMPANY WEBSITES
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THEORETICAL VERIFICATION OF THE SCALING RELATION TO DETERMINE SURFACE FRACTAL DIMENSION OF POROUS MEDIA 被引量:2
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作者 张宝泉 刘秀凤 李绍芬 《Transactions of Tianjin University》 EI CAS 2000年第2期181-184,共页
A simplified procedure is developed to acquire the surface fractal dimension of porous media utilizing the PSD information from mercury porosimetry or other analyses.The self similarity of the inner surface of Sierpi... A simplified procedure is developed to acquire the surface fractal dimension of porous media utilizing the PSD information from mercury porosimetry or other analyses.The self similarity of the inner surface of Sierpinski sponge is analyzed,the result of which demonstrates that the inner surface of Sierpinski sponge is not scale invariant over the whole range of scale transformations.By applying the simplified procedure to analyze and treat the PSD information of Sierpinski sponge over the scale invariant range,it is found that the surface fractal dimension calculated by the scaling relation is in very good agreement with its theoretical value,which virtually provides a theoretical affirmation of the method. 展开更多
关键词 FRACTAL surface fractal dimension Sierpinski sponge
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An Economical Approach to Four-dimensional Variational Data Assimilation 被引量:26
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作者 王斌 刘娟娟 +5 位作者 王曙东 成巍 刘娟 刘成思 Qingnong XIAO Ying-Hwa KUO 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2010年第4期715-727,共13页
Four-dimensional variational data assimilation (4DVar) is one of the most promising methods to provide optimal analysis for numerical weather prediction (NWP). Five national NWP centers in the world have successfu... Four-dimensional variational data assimilation (4DVar) is one of the most promising methods to provide optimal analysis for numerical weather prediction (NWP). Five national NWP centers in the world have successfully applied 4DVar methods in their global NWPs, thanks to the increment method and adjoint technique. However, the application of 4DVar is still limited by the computer resources available at many NWP centers and research institutes. It is essential, therefore, to further reduce the computational cost of 4DVar. Here, an economical approach to implement 4DVar is proposed, using the technique of dimension- reduced projection (DRP), which is called "DRP-4DVar." The proposed approach is based on dimension reduction using an ensemble of historical samples to define a subspace. It directly obtains an optimal solution in the reduced space by fitting observations with historical time series generated by the model to form consistent forecast states, and therefore does not require implementation of the adjoint of tangent linear approximation. To evaluate the performance of the DRP-4DVar on assimilating different types of mesoscale observations, some observing system simulation experiments are conducted using MM5 and a comparison is made between adjoint-based 4DVar and DRP-4DVar using a 6-hour assimilation window. 展开更多
关键词 4DvAR ADJOINT dimension reduction historical sample observing system simulation experiment
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GIS-based landslide susceptibility mapping using hybrid integration approaches of fractal dimension with index of entropy and support vector machine 被引量:11
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作者 ZHANG Ting-yu HAN Ling +3 位作者 ZHANG Heng ZHAO Yong-hua LI Xi-an ZHAO Lei 《Journal of Mountain Science》 SCIE CSCD 2019年第6期1275-1293,共19页
The loess area in the northern part of Baoji City, Shaanxi Province, China is a region with frequently landslide occurrences. The main aim of this study is to quantitatively predict the extent of landslides using the ... The loess area in the northern part of Baoji City, Shaanxi Province, China is a region with frequently landslide occurrences. The main aim of this study is to quantitatively predict the extent of landslides using the index of entropy model(IOE), the support vector machine model(SVM) and two hybrid models namely the F-IOE model and the F-SVM model constructed by fractal dimension. First, a total of 179 landslides were identified and landslide inventory map was produced, with 70%(125) of the landslides which was optimized by 10-fold crossvalidation being used for training purpose and the remaining 30%(54) of landslides being used for validation purpose. Subsequently, slope angle, slope aspect, altitude, rainfall, plan curvature, distance to rivers, land use, distance to roads, distance to faults, normalized difference vegetation index(NDVI), lithology, and profile curvature were considered as landslide conditioning factors and all factor layers were resampled to a uniform resolution. Then the information gain ratio of each conditioning factors was evaluated. Next, the fractal dimension for each conditioning factors was calculated and the training dataset was used to build four landslide susceptibility models. In the end, the receiver operating characteristic(ROC) curves and three statistical indexes involving positive predictive rate(PPR), negative predictive rate(NPR) and accuracy(ACC) were applied to validate and compare the performance of these four models. The results showed that the F-SVM model had the highest PPR, NPR, ACC and AUC values for training and validation datasets, respectively, followed by the F-IOE model.Finally, it is concluded that the F-SVM model performed best in all models, the hybrid model built by fractal dimension has advantages than original model, and can provide reference for local landslide prevention and decision making. 展开更多
关键词 GIS LANDSLIDE SUSCEPTIBILITY Hybrid model FRACTAL dimension
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Estimation and Prediction of the Condition of the Vehicle Engine Based on the Correlation Dimension 被引量:8
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作者 LiuChun ZhangLaibin WangZhaohui 《Petroleum Science》 SCIE CAS CSCD 2004年第1期45-49,共5页
This paper applies the fractal dimension as a characteristic to describe the engine抯 operating condition and its developmental trend. A correlation dimension is one of the quantities that are usually used to characte... This paper applies the fractal dimension as a characteristic to describe the engine抯 operating condition and its developmental trend. A correlation dimension is one of the quantities that are usually used to characterize a strange attractor. With the operation of the phase space reconstruction, respective correlation dimensions of a series of vibration signals obtained under different conditions are calculated to find the intrinsic relationship between the indicator and the operating condition. The experiment result shows that the correlation dimension is sensitive to the condition evolution and convenient for the identification of abnormal operational states. In advanced prognostic algorithm based on the BP neural network is then applied on the correlation dimensions to predict the short-term running conditions in order to avoid severe faults and realize in-time maintenance. Experimental results are presented to illustrate the proposed methodology. 展开更多
关键词 vehicle engine condition estimation correlation dimension PREDICTION
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Volume fractal dimension of soil particles and relationships with soil physical-chemical properties and plant species diversity in an alpine grassland under different disturbance degrees 被引量:21
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作者 YanYan LIU YanMing GONG +1 位作者 Xin WANG YuKun HU 《Journal of Arid Land》 SCIE CSCD 2013年第4期480-487,共8页
Fractal geometry is an important method in soil science,and many studies have used fractal theory to examine soil properties and the relationships with other eco-environmental factors.However,there have been few studi... Fractal geometry is an important method in soil science,and many studies have used fractal theory to examine soil properties and the relationships with other eco-environmental factors.However,there have been few studies examining soil particle volume fractal dimension in alpine grasslands.To study the volume fractal dimension of soil particles (D) and its relationships with soil salt,soil nutrient and plant species diversity,we conducted an experiment on an alpine grassland under different disturbance degrees:non-disturbance (N0),light disturbance (L),moderate disturbance (M) and heavy disturbance (H).The results showed that (1) Ds varied from 2.573 to 2.635 among the different disturbance degrees and increased with increasing degrees of disturbance.(2) Shannon-Wiener diversity index,Pielou's evenness index and Margalef richness index reached their highest values at the M degree,indicating that moderate disturbance is beneficial to the increase of plant species diversity.(3) In the L and M degrees,there was a significant positive correlation between D and clay content and a significant negative correlation between D and soil organic matter (SOM).In the H degree,D was significantly and positively correlated with total salt (TS).The results suggested that to a certain extent,D can be used to characterize the uniformity of soil texture in addition to soil fertility characteristics.(4) For the L degree,there was a significant negative correlation between D and the Shannon-Wiener diversity index; while for the M degree,there was a significant negative correlation between D and Pielou's evenness index. 展开更多
关键词 alpine grassland disturbance degree volume fractal dimension of soil particles species diversity
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Relevance between abutment pressure and fractal dimension of crack network induced by mining 被引量:8
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作者 Gao Mingzhong Jin Wencheng +1 位作者 Dai Zhixu Xie Jing 《International Journal of Mining Science and Technology》 SCIE EI 2013年第6期925-930,共6页
Based on the geological conditions of coal mining face No.15-14120 at No.8 mine of Pingdingshan coal mining group,the real-time evolution of coal-roof crack network with working face advancing was collected with the h... Based on the geological conditions of coal mining face No.15-14120 at No.8 mine of Pingdingshan coal mining group,the real-time evolution of coal-roof crack network with working face advancing was collected with the help of intrinsically safe borehole video instrument.And according to the geology of this working face,a discrete element model was calculated by UDEC.Combining in situ experimental data with numerical results,the relationship between the fractal dimension of boreholes'wall and the distribution of advanced abutment pressure was studied under the condition of mining advance.The results show that the variation tendency of fractal dimension and the abutment pressure has the same characteristic value.The distance between working face and the peak value of the abutment pressure has a slight increasing trend with the advancing of mining-face.When the working face is set as the original point,the trend of fractal dimension from the far place to the origin can be divided into three phases:constant,steady increasing and constant.And the turning points of these phases are the max-influencing distance(50 m)and peak value(15 m)of abutment pressure. 展开更多
关键词 BOREHOLES Coal mines Cracks Finite difference method Fractal dimension
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On the Techniques of Communicative Dimensional Transformation Between Hypotaxis and Parataxis in Tourist Publicity C-E Translation
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作者 肖付良 《大学英语教学与研究》 2016年第1期49-50,共2页
Communicative dimension,as one of the three key dimensions of eco-translatology,plays a very important role in translating tourist publicity materials.With the communicative dimensional transformation techniques of pa... Communicative dimension,as one of the three key dimensions of eco-translatology,plays a very important role in translating tourist publicity materials.With the communicative dimensional transformation techniques of parataxis and hypotaxis,translators should exert their subjectivity and creativity to achieve in maximizing the degree of holistic adaptation and selection for achieving successful translations. 展开更多
关键词 大学 英语 课外阅读 阅读材料
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