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Analysis of Daily Life,Spiritual Comfort,and Fall Safety Care Needs of Elderly People in Urban and Rural Areas
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作者 Fang Zheng Xiaojing Tang Xinyue Zhang 《Journal of Clinical and Nursing Research》 2025年第1期157-163,共7页
Objective: To examine the daily life care, spiritual comfort, and fall safety care needs of the elderly in urban and rural areas of Tangshan, along with their influencing factors. Methods: From August 2022 to April 20... Objective: To examine the daily life care, spiritual comfort, and fall safety care needs of the elderly in urban and rural areas of Tangshan, along with their influencing factors. Methods: From August 2022 to April 2023, an investigation was conducted among urban and rural elderly individuals aged over 75 years in Tangshan City using the Activities of Daily Living Scale, the Revised Community Elderly Fall Risk Assessment Tool, and the Loneliness Scale. Results: The study included 750 urban and 740 rural elderly individuals aged over 75 years. Matrix analysis revealed a significant proportion of fall safety care needs across various daily life and spiritual care requirements. Multiple factor analysis indicated that advanced age, lower education levels, a greater number of chronic diseases, and lower levels of family and social support were associated with higher care demands among the elderly in both urban and rural areas. These differences were statistically significant (P < 0.05). Conclusion: The elderly in urban and rural areas demonstrate a high demand for fall safety care. Particular attention should be given to individuals with lower education levels, those who are widowed, those with multiple chronic diseases, and those with low levels of family and social support to better meet the diverse care needs of this population. 展开更多
关键词 Elderly people Daily life care needs Spiritual comfort needs Fall safety care needs matrix analysis
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Histologic analysis and long-term effect of acellular dermal matrix combined with autologous thin split-thickness skin graft
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作者 韩立会 《外科研究与新技术》 2011年第2期133-133,共1页
Objective To evaluate the long-term therapeutic effect and histologic result of ADM combined with autologous thin split-thickness skin graft.Methods 23 patients were treated with acellalar dermal matrix(ADM) combined ... Objective To evaluate the long-term therapeutic effect and histologic result of ADM combined with autologous thin split-thickness skin graft.Methods 23 patients were treated with acellalar dermal matrix(ADM) combined with autoiogous 展开更多
关键词 Histologic analysis and long-term effect of acellular dermal matrix combined with autologous thin split-thickness skin graft
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Investigation and Countermeasures of the Development of Chinese Pharmaceutical E-commerce in the B2C Model Based on PEST-SWOT Analysis
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作者 Xiu Yu Wang Shuling 《Asian Journal of Social Pharmacy》 2023年第4期398-405,共8页
Objective To analyze the problems of pharmaceutical e-commerce and provide strategies for its development in the future B2C mode since drug network management has great potential in China.Methods By collecting,identif... Objective To analyze the problems of pharmaceutical e-commerce and provide strategies for its development in the future B2C mode since drug network management has great potential in China.Methods By collecting,identifying,and conducting literature research,PEST-SWOT identification and positioning of pharmaceutical e-commerce in the B2C mode were carried out.Results and Conclusion A PEST-SWOT analysis matrix was established to analyze the status of B2C pharmaceutical e-commerce,and to summarize its advantages,disadvantages,opportunities and threats from four perspectives of politics,economy,society and technology.Suggestions on cultivating compound talents proficient in medicine and e-commerce,exploring online payment methods for medical insurance,integration of upstream and downstream of the industrial chain and data sharing are put forward to promote the healthy and long-term development of pharmaceutical e-commerce under the background of big data. 展开更多
关键词 pharmaceutical e-commerce B2C PEST-SWOT analysis matrix
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Spatial Dislocation Analysis of Tourism Economy and Its Influencing Factors in Jiangsu Province 被引量:1
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作者 Yuxiang Zheng Yue Zhu 《Journal of Economic Science Research》 2021年第1期13-22,共10页
Taking 13 prefecture-level cities in Jiangsu Province as the research object,based on the theory of spatial dislocation,the gravity model and two-dimensional composite matrix method are used to analyze the spatial dis... Taking 13 prefecture-level cities in Jiangsu Province as the research object,based on the theory of spatial dislocation,the gravity model and two-dimensional composite matrix method are used to analyze the spatial dislocation between tourism resources,permanent population and other factors in Jiangsu Province and tourism revenue.The results show that the population center,the center of tourism resources,the center of tourist numbers,the center of economic development,and the center of tourism revenue of Jiangsu Province are all biased toward the southern part of Jiangsu Province.From the analysis of four sets of two-dimensional composite matrixes,13 prefecture-level cities have synchronized coordination and also have positive and negative dislocation types.Southern Jiangsu has the best synchronization and coordination,and northern Jiangsu has a strong negative dislocation trend;the combination of tourist numbers and tourism revenue is the strongest,but the dislocation is weak;population and tourism revenue have a strong positive dislocation trend;there is a strong negative dislocation trend between economic development and tourism revenue;the matrix combination of Nanjing,Wuxi and Suzhou has good synchronization;the city of Xuzhou in northern Jiangsu has a strong negative dislocation.In view of the results of spatial dislocation analysis,suggestions for improvement and optimization are put forward to promote the high-quality development of tourism in Jiangsu Province. 展开更多
关键词 Jiangsu province Tourism revenue Spatial dislocation matrix analysis
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Dynamic Recrystallization Behavior of Bimodal Size SiCpReinforced Mg Matrix Composite during Hot Deformation 被引量:2
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作者 Cui-Ju Wang Kun-Kun Deng +1 位作者 Shan-Shan Zhou Wei Liang 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2016年第6期527-537,共11页
The(submicron+micron) bimodal size Si Cp-reinforced Mg matrix composite was compressed at the temperature of 270–420 °C and strain rate of 0.001–1 s^-1. Then, dynamic recrystallization(DRX) behavior of the... The(submicron+micron) bimodal size Si Cp-reinforced Mg matrix composite was compressed at the temperature of 270–420 °C and strain rate of 0.001–1 s^-1. Then, dynamic recrystallization(DRX) behavior of the composite was investigated by thermodynamic method and verified by microstructure analysis. Results illustrated that the composite possess the lower critical strain and higher DRX ratio as compared to monolithic Mg alloys during hot deformation process. The predicted DRX ratio increased with the proceeding of compression, which was well consistent with the experimental value. Results from thermodynamic calculation suggested that the occurrence of DRX could be promoted by Si Cp, which would be further proved by microstructure analysis. Formation of particle deformation zone around micron Si Cp played a significant role in promoting DRX nucleation. Nevertheless, the distribution of submicron Si Cp was increasingly uniform with the proceeding of compression, which could fully restrain grain growth. Therefore, the corporate effects of micron and submicron Si Cp on DRX contributed to the improvement of DRXed ratio and the refinement of grain size for the composite during compression process. 展开更多
关键词 Magnesium matrix composite Deformation Dynamic recrystallization Microstructure Thermodynamic analysis
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Mixed Matrix Membranes of Polysulfone/Polyimide Reinforced with Modified Zeolite Based Filler: Preparation, Properties and Application 被引量:1
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作者 Sedra Tul Muntha Muhammad Siddiq +1 位作者 Ayesha Kausar Anum Khan 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2018年第1期65-77,共13页
In this work, polysulfone/polyimide(PSf/PI) mixed matrix membranes were fabricated by reinforcement of modified zeolite(MZ) particles through solution casting method for investigation of antibacterial activity aga... In this work, polysulfone/polyimide(PSf/PI) mixed matrix membranes were fabricated by reinforcement of modified zeolite(MZ) particles through solution casting method for investigation of antibacterial activity against two gram negative bacteria(Salmonella typhi, Klebsella pneumonia) and two gram positive bacteria(Staphylococcus aureus, Bacillus subtilis). The modified zeolite particles were incorporated to PSf and PI matrix and the influence of these particles on thermal, mechanical and structural properties was evaluated. The morphological evolution was investigated through scanning electron microscopy(SEM) and transmission electron microscopy(TEM) analysis, which revealed good compatibility between organic polymer matrix and inorganic filler. Mechanical stability was investigated by tensile testing while thermal analysis was evaluated by thermogravimetric analysis(TGA) and differential scanning calorimetry(DSC). This revealed improvement in thermal properties with increasing filler concentration from 1 wt% to 10 wt%. Structural analysis was successfully done using X-ray diffraction analysis(XRD) and Fourier transform infrared(FTIR) spectroscopy. Solvent content of fabricated mixed matrix membranes was observed to decrease while moving from more hydrophilic to less hydrophilic solvent. However, addition of filler content enhanced the porosity of fabricated membranes. The synthesized mixed matrix membranes exhibited good antibacterial activity and the highest activity was shown by PSf/PI/MZ mixed matrix membrane. Therefore, the combination effect of PSf, PI and MZ sufficiently enhanced the antibacterial activity of mixed matrix membranes. 展开更多
关键词 Modified zeolite Polysulfone/polyimide blend membrane Mixed matrix membrane Thermal analysis Antibacterial activity
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The Application of Sensitivity Analysis on Comprehensive Transportation Evaluation
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作者 Xuemei Li 《Chinese Business Review》 2004年第6期21-25,共5页
Comprehensive transportation evaluation objects using multi-objective decision method is a process of choosing the best one from a few objects through calculating, analyzing, and comparing the index system. The result... Comprehensive transportation evaluation objects using multi-objective decision method is a process of choosing the best one from a few objects through calculating, analyzing, and comparing the index system. The result may be different because of the difference of the index weight and index value. Therefore, sensitivity analysis should be one of the necessary parts of the decision-making. It is desired to give the index with higher sensitivity and its varying scope to control the index strictly during the execution process. This paper derives transfer index weight, which changes the rank evaluation order of the projects. Meanwhile, a simple, effective and practical method based on sensitivity district and sensitivity matrix is proposed for the sensitivity analysis of decision-making. As an example, the index sensitivity in decision-making of some provinces comprehensive transportation objects, and their influence on the final decision are discussed. 展开更多
关键词 sensitivity analysis comprehensive transportation evaluation sensitivity matrix
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Modeling mechanism and extension of GM (1,1) 被引量:17
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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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Parameters Sensitivity Characteristics of Highly Integrated Valve-Controlled Cylinder Force Control System 被引量:8
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作者 Kai-Xian Ba Bin Yu +4 位作者 Xiang-Dong Kong Chun-He Li Qi-Xin Zhu Hua-Long Zhao Ling-Jian Kong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2018年第2期159-175,共17页
Nowadays, a highly integrated valve?controlled cylinder(HIVC) is applied to drive the joints of legged robots. Although the adoption of HIVC has resulted in high?performance robot control, the hydraulic force system s... Nowadays, a highly integrated valve?controlled cylinder(HIVC) is applied to drive the joints of legged robots. Although the adoption of HIVC has resulted in high?performance robot control, the hydraulic force system still has problems, such as strong nonlinearity, and time?varying parameters. This makes HIVC force control very diffcult and complex. How to improve the control performance of the HIVC force control system and find the influence rule of the system parameters on the control performance is very significant. Firstly, the mathematical model of HIVC force control system is established. Then the mathematical expression for parameter sensitivity matrix is obtained by applying matrix sensitivity analysis(PSM). Then, aimed at the sinusoidal response under(three factors and three levels) working conditions, the simulation and the experiment are conducted. While the error between the simulation and experiment can’t be avoided. Therefore, combined with the range analysis, the error in the two performance indexes of sinusoidal response under the whole working condition is analyzed. Besides, the sensitivity variation pattern for each system parameter under the whole working condition is figured out. Then the two sensitivity indexes for the three system parameters, which are supply pressure, proportional gain and initial displacement of piston, are proved experimentally. The proposed method significantly reveals the sensitivity characteristics of HIVC force control system, which can make the contribution to improve the control performance. 展开更多
关键词 Highly integrated valve?controlled cylinder system Force control system matrix sensitivity analysis Orthogonal test design Sensitivity index
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Soft Sensing Modelling Based on Optimal Selection of Secondary Variables and Its Application 被引量:2
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作者 Qi Li Cheng Shao 《International Journal of Automation and computing》 EI 2009年第4期379-384,共6页
The composition of the distillation column is a very important quality value in refineries, unfortunately, few hardware sensors are available on-line to measure the distillation compositions. In this paper, a novel me... The composition of the distillation column is a very important quality value in refineries, unfortunately, few hardware sensors are available on-line to measure the distillation compositions. In this paper, a novel method using sensitivity matrix analysis and kernel ridge regression (KRR) to implement on-line soft sensing of distillation compositions is proposed. In this approach, the sensitivity matrix analysis is presented to select the most suitable secondary variables to be used as the soft sensor's input. The KRR is used to build the composition soft sensor. Application to a simulated distillation column demonstrates the effectiveness of the method. 展开更多
关键词 Distillation column sensitivity matrix analysis ridge regression kernel ridge regression (KRR) soft sensor
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Microarray analysis of extracellular matrix genes expression in myocardium of mouse with Coxsackie virus B_3 myocarditis 被引量:6
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作者 张召才 李双杰 +3 位作者 杨英珍 陈瑞珍 葛均波 陈灏珠 《Chinese Medical Journal》 SCIE CAS CSCD 2004年第8期1228-1231,共4页
Background Extracellular matrix (ECM) orchestrates cell behaviour including growth, death, apoptosis, adhesion, migration, and invasion by activating several signalling pathways Certain components of ECM, such as ... Background Extracellular matrix (ECM) orchestrates cell behaviour including growth, death, apoptosis, adhesion, migration, and invasion by activating several signalling pathways Certain components of ECM, such as integrins, may act as receptors or co-receptors of enterovirus ECM-activated gene expressions in myocardium of viral heart disease including myocarditis and partial cardiomyopathy remain elusive This study was to investigate the expression of ECM-activated genes in myocardium of mouse with viral myocarditis Methods BALB/c mice were infected with Coxsackie virus B 3 (CVB 3) to establish an animal model of myocarditis Uninfected mice were also prepared and served as controls Specific mRNA expression pattern in myocarditic mouse heart was analysed by an in-house cDNA microarray containing 8192 genes Overexpressed ECM genes were selected and subsequently confirmed by Northern blot analysis Results Nine ECM genes were isolated, from the array of 8192 genes, as overexpressed genes in hearts of myocarditic mice in comparison with controls Subsequent Northern blot analysis confirmed that four of the nine genes were highly expressed Expression of these four genes, Fin15, ILk, Lamr1 and ADAMTS-1, has not been reported previously to be induced by Coxsackie virus Conclusion CVB 3-induced myocarditis is associated with gene expression profiles of certain ECM components 展开更多
关键词 oligonucleotide array sequence analysis · extracellular matrix · myocarditis · Coxsackie virus B
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MATRIX ANALYSIS TO ADDITIVE SCHWARZ METHODS 被引量:1
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作者 Sun, JC Chan, TF 《Journal of Computational Mathematics》 SCIE CSCD 1995年第4期325-336,共12页
Matrix analysis on additive Schwarz methods as preconditioners is given in this paper. Both cases of with and without coarse mesh are considered. It is pointed out that an advantage of matrix analysis is to obtain mor... Matrix analysis on additive Schwarz methods as preconditioners is given in this paper. Both cases of with and without coarse mesh are considered. It is pointed out that an advantage of matrix analysis is to obtain more exact upper hound. Our numerical tests access the estimations. 展开更多
关键词 TA matrix analysis TO ADDITIVE SCHWARZ METHODS BA
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Identifying the major fluorescent components responsible for ultrafiltration membrane fouling in different water sources 被引量:6
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作者 Weiguang Sun Jun Nan +1 位作者 Jia Xing Jiayu Tian 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2016年第7期215-223,共9页
Three-dimensional fluorescence excitation–emission matrix(EEM) coupled with parallel factor analysis(PARAFAC) was performed for a total of 18 water samples taken from three water sources(two lakes and one wastew... Three-dimensional fluorescence excitation–emission matrix(EEM) coupled with parallel factor analysis(PARAFAC) was performed for a total of 18 water samples taken from three water sources(two lakes and one wastewater treatment plant(WWTP) secondary effluent),with the purpose of identifying the major ultrafiltration(UF) membrane foulants in different water sources. Three fluorescent components(C1, C2 and C3) were identified,which represented terrestrially derived humic-like substances(C1), microbially derived humic-like substances(C2), and protein-like substances(C3). The correlations between the different fluorescent components and UF membrane fouling were analyzed. It was shown that for the WWTP secondary effluent, all three components(C1, C2 and C3) made a considerable contribution to the irreversible and total fouling of the UF membrane.However, for the two lakes, only the C3 exhibited a strong correlation with membrane fouling, indicating that the protein-like substances were the major membrane foulants in the lake waters. Significant attachment of C1, C2 and C3 to the UF membrane was also confirmed by mass balance analyses for the WWTP secondary effluent; while the attachment of C1 and C2 was shown to be negligible for the two lakes. The results may provide basic formation for developing suitable fouling control strategies for sustainable UF processes. 展开更多
关键词 Membrane fouling Organic substances Three-dimensional fluorescence matrix Parallel factor analysis Correlation analysis
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Image registration based on matrix perturbation analysis using spectral graph 被引量:1
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作者 冷成财 田铮 +1 位作者 李婧 丁明涛 《Chinese Optics Letters》 SCIE EI CAS CSCD 2009年第11期996-1000,共5页
We present a novel perspective on characterizing the spectral correspondence between nodes of the weighted graph with application to image registration. It is based on matrix perturbation analysis on the spectral grap... We present a novel perspective on characterizing the spectral correspondence between nodes of the weighted graph with application to image registration. It is based on matrix perturbation analysis on the spectral graph. The contribution may be divided into three parts. Firstly, the perturbation matrix is obtained by perturbing the matrix of graph model. Secondly, an orthogonal matrix is obtained based on an optimal parameter, which can better capture correspondence features. Thirdly, the optimal matching matrix is proposed by adjusting signs of orthogonal matrix for image registration. Experiments on both synthetic images and real-world images demonstrate the effectiveness and accuracy of the proposed method. 展开更多
关键词 Image registration based on matrix perturbation analysis using spectral graph THH LH VHH SAR Ga
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A Revisited Definition of the Three Solute Descriptors Related to the Van der Waals Forces in Solutions 被引量:2
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作者 Paul Laffort 《Open Journal of Physical Chemistry》 2016年第4期86-100,共15页
It is currently admitted that the intermolecular forces implicated in Gas Liquid Chromatography (GLC) can be expressed as a product of parameters (or descriptors) of solutes and of parameters of solvents. The present ... It is currently admitted that the intermolecular forces implicated in Gas Liquid Chromatography (GLC) can be expressed as a product of parameters (or descriptors) of solutes and of parameters of solvents. The present study is limited to those of solutes, and among them the three ones are involved in the Van der Waals forces, whereas the two ones involved in the hydrogen bonding are left aside at this stage. These three studied parameters, which we call δ, ω and ε, respectively reflect the three types of Van der Waals forces: dispersion, orientation or polarity strictly speaking, and induction-polarizability. These parameters have been experimentally obtained in previous studies for 121 Volatile Organic Compounds (VOC) via an original Multiplicative Matrix Analysis (MMA) applied to a superabundant and accurate GLC data set. Then, also in previous studies, attempts have been made to predict these parameters via a Simplified Molecular Topology procedure (SMT). Because these last published results have been somewhat disappointing, a promising new strategy of prediction is developed and detailed in the present article. 展开更多
关键词 Van der Waals Intermolecular Forces Solute Descriptors Gas Liquid Chromatography Chemo Informatics Multiplicative matrix analysis
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Interface characterization of the discontinuously reinforced metal matrix composites based on wavelet analysis of acoustic emission behaviour 被引量:5
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《Chinese Science Bulletin》 SCIE CAS 1998年第9期791-792,共2页
关键词 Interface characterization of the discontinuously reinforced metal matrix composites based on wavelet analysis of acoustic emission behaviour
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Determination of Three-Dimensional Structures of Oridonin in Solution by NOESY Spectrum and Molecular Mechanics Calculation
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作者 YANG Yan-wu , JI Ang and HE Bing-lin (Institute of Polymer Chemistry, Nankai University, Tianjin, 300071)XU Xiao-long, QIU Jian-qing, WANG De-hua and QIAN Bao-gong(Laboratory of Magnetic Resonance and Atomic and Molecular Physics, WuhanInstitute of Physics, The Chinese Academy of Sciences, Wuhan, 430071)ZHAO Qing-zhi(Department of Organic Chemistry, Henan University of Medicinal Science, Zhengzhou, 450052) 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1993年第3期240-245,共6页
The phase sensitive NOESY spectrum of oridonin was treated using Full Relaxation Matrix Analysis(FRMA) approach, and the cross relaxation rates of proton pairs were obtained by diagonalizing the NOE matrix of oridonin... The phase sensitive NOESY spectrum of oridonin was treated using Full Relaxation Matrix Analysis(FRMA) approach, and the cross relaxation rates of proton pairs were obtained by diagonalizing the NOE matrix of oridonin. The inter proton distances were calculated according to 1/r6 ij ∝σij. The three-dimensional structure of oridonin in solution was calculated by the combination of WUPH, WUPH-S method with molecular mechanics minimization on the basis of NMR experiment. 展开更多
关键词 ORIDONIN Solution conformation Molecular mechanics Complete relax-ation matrix analysis
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MATRIX ANALYSIS ON LEADING TERM OF CONDITION NUMBER FOR ADDITIVE SCHWARZ METHODS
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作者 Jia-chang Sun (R & D Center of Paraller Software, Laboratory for Computer Science, Institute of Software, Chinese Academy of Sciences) 《Journal of Computational Mathematics》 SCIE CSCD 2001年第2期157-166,共10页
It is well known the order of preconditioned matrix by using additive Schwarz methods. In order to estimate the resulted PCG iteration counts, the related leading term brfore the order is given in this paper.
关键词 additive Schwarz method PCG matrix analysis
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The Kemeny’s Constant and Spanning Trees of Hexagonal Ring Network
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作者 Shahid Zaman Ali N.A.Koam +1 位作者 Ali Al Khabyah Ali Ahmad 《Computers, Materials & Continua》 SCIE EI 2022年第12期6347-6365,共19页
Spanning tree(τ)has an enormous application in computer science and chemistry to determine the geometric and dynamics analysis of compact polymers.In the field of medicines,it is helpful to recognize the epidemiology... Spanning tree(τ)has an enormous application in computer science and chemistry to determine the geometric and dynamics analysis of compact polymers.In the field of medicines,it is helpful to recognize the epidemiology of hepatitis C virus(HCV)infection.On the other hand,Kemeny’s constant(Ω)is a beneficial quantifier characterizing the universal average activities of a Markov chain.This network invariant infers the expressions of the expected number of time-steps required to trace a randomly selected terminus state since a fixed beginning state si.Levene and Loizou determined that the Kemeny’s constant can also be obtained through eigenvalues.Motivated by Levene and Loizou,we deduced the Kemeny’s constant and the number of spanning trees of hexagonal ring network by their normalized Laplacian eigenvalues and the coefficients of the characteristic polynomial.Based on the achieved results,entirely results are obtained for the M鯾ius hexagonal ring network. 展开更多
关键词 matrix analysis hexagonal ring network Kemeny’s constant Spanning tree
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Systematic Elastostatic Stiffness Model of Over-Constrained Parallel Manipulators Without Additional Constraint Equations
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作者 Chao Yang Wenyong Yu +2 位作者 Wei Ye Qiaohong Chen Fengli Huang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第4期258-276,共19页
The establishment of an elastostatic stiffness model for over constrained parallel manipulators(PMs),particularly those with over constrained subclosed loops,poses a challenge while ensuring numerical stability.This s... The establishment of an elastostatic stiffness model for over constrained parallel manipulators(PMs),particularly those with over constrained subclosed loops,poses a challenge while ensuring numerical stability.This study addresses this issue by proposing a systematic elastostatic stiffness model based on matrix structural analysis(MSA)and independent displacement coordinates(IDCs)extraction techniques.To begin,the closed-loop PM is transformed into an open-loop PM by eliminating constraints.A subassembly element is then introduced,which considers the flexibility of both rods and joints.This approach helps circumvent the numerical instability typically encountered with traditional constraint equations.The IDCs and analytical constraint equations of nodes constrained by various joints are summarized in the appendix,utilizing multipoint constraint theory and singularity analysis,all unified within a single coordinate frame.Subsequently,the open-loop mechanism is efficiently closed by referencing the constraint equations presented in the appendix,alongside its elastostatic model.The proposed method proves to be both modeling and computationally efficient due to the comprehensive summary of the constraint equations in the Appendix,eliminating the need for additional equations.An example utilizing an over constrained subclosed loops demonstrate the application of the proposed method.In conclusion,the model proposed in this study enriches the theory of elastostatic stiffness modeling of PMs and provides an effective solution for stiffness modeling challenges they present. 展开更多
关键词 Parallel manipulator Elastostatic stiffness model matrix structural analysis Subassembly element Independent displacement coordinates
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