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Dimension.xpand.plus与日立7600生化分析仪检测结果的可比性研究 被引量:2
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作者 曾宇娟 黄子初 +1 位作者 刘光金 陈苑芬 《国际检验医学杂志》 CAS 2013年第20期2754-2755,共2页
目的探讨美国西门子Dimension.xpand.plus自动生化分析仪与日立7600自动生化仪检测结果之间是否具有可比性。方法按照EP9-A文件的要求选取实验标本,将Dimension.xpand.plus自动生化分析仪作为比对仪器,日立7600作为参考仪器,观察二者之... 目的探讨美国西门子Dimension.xpand.plus自动生化分析仪与日立7600自动生化仪检测结果之间是否具有可比性。方法按照EP9-A文件的要求选取实验标本,将Dimension.xpand.plus自动生化分析仪作为比对仪器,日立7600作为参考仪器,观察二者之间在尿素(Urea)、血清总蛋白(TP)、天门冬氨酸氨基转移酶(AST)和血糖(GLU)等4个检测项目上面的检测结果,并使用SPSS 13.0软件对之进行计算、分析,得出相关系数(r)和回归方程Y=bX+a。结果日立7600检测Urea、TP、AST和GLU的结果分别为(12.2±6.1)mmol/L、(46.58±12)mmol/L、(144.9±70.8)U/L、(16.9±8.5)mmol/L;Dimension.xpand.plus检测Urea、TP、AST和GLU的结果分别为(12.1±6.2)mmol/L、(47.62±12)mmol/L、(145.1±71.1)U/L、(17.1±8.6)mmol/L。2台生化仪检测结果比较差异无统计学意义(P>0.05)。结论 Dimension.xpand.plus与日立7600全自动生化仪检测结果具有可比性,在临床上具有相同的效果。 展开更多
关键词 dimension xpand PLUS 日立7600生化分析仪 比对试验 可比性
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Fractal analysis of major faults and fractal dimension of lineaments in the Indo-Gangetic Plain on a regional scale
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作者 Vipin Chauhan Jagabandhu Dixit 《Earthquake Science》 2024年第2期107-121,共15页
The Indo-Gangetic Plain(IGP)is one of the most seismically vulnerable areas due to its proximity to the Himalayas.Geographic information system(GIS)-based seismic characterization of the IGP was performed based on the... The Indo-Gangetic Plain(IGP)is one of the most seismically vulnerable areas due to its proximity to the Himalayas.Geographic information system(GIS)-based seismic characterization of the IGP was performed based on the degree of deformation and fractal dimension.The zone between the Main Boundary Thrust(MBT)and the Main Central Thrust(MCT)in the Himalayan Mountain Range(HMR)experienced large variations in earthquake magnitude,which were identified by Number-Size(NS)fractal modeling.The central IGP zone experienced only moderate to low mainshock levels.Fractal analysis of earthquake epicenters reveals a large scattering of earthquake epicenters in the HMR and central IGP zones.Similarly,the fault fractal analysis identifies the HMR,central IGP,and south-western IGP zones as having more faults.Overall,the seismicity of the study region is strong in the central IGP,south-western IGP,and HMR zones,moderate in the western and southern IGP,and low in the northern,eastern,and south-eastern IGP zones. 展开更多
关键词 geospatial analysis fractal modeling seismicity pattern fractal dimension
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Higher-dimensional Chen-Lee-Liu equation and asymmetric peakon soliton
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作者 韩巧红 贾曼 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期224-229,共6页
Integrable systems play a crucial role in physics and mathematics.In particular,the traditional(1+1)-dimensional and(2+1)-dimensional integrable systems have received significant attention due to the rarity of integra... Integrable systems play a crucial role in physics and mathematics.In particular,the traditional(1+1)-dimensional and(2+1)-dimensional integrable systems have received significant attention due to the rarity of integrable systems in higher dimensions.Recent studies have shown that abundant higher-dimensional integrable systems can be constructed from(1+1)-dimensional integrable systems by using a deformation algorithm.Here we establish a new(2+1)-dimensional Chen-Lee-Liu(C-L-L)equation using the deformation algorithm from the(1+1)-dimensional C-L-L equation.The new system is integrable with its Lax pair obtained by applying the deformation algorithm to that of the(1+1)-dimension.It is challenging to obtain the exact solutions for the new integrable system because the new system combines both the original C-L-L equation and its reciprocal transformation.The traveling wave solutions are derived in implicit function expression,and some asymmetry peakon solutions are found. 展开更多
关键词 higher dimensional Chen-Lee-Liu equation Lax integrable system deformation algorithm implicit traveling wave solutions
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Study on creep deformation and energy development of underground surrounding rock under four‐dimensional support
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作者 Zhanguo Ma Junyu Sun +3 位作者 Peng Gong Pengfei Yan Nan Cui Ruichong Zhang 《Deep Underground Science and Engineering》 2024年第1期25-38,共14页
There is an urgent need to develop optimal solutions for deformation control of deep high‐stress roadways,one of the critical problems in underground engineering.The previously proposed four‐dimensional support(here... There is an urgent need to develop optimal solutions for deformation control of deep high‐stress roadways,one of the critical problems in underground engineering.The previously proposed four‐dimensional support(hereinafter 4D support),as a new support technology,can set the roadway surrounding rock under three‐dimensional pressure in the new balanced structure,and prevent instability of surrounding rock in underground engineering.However,the influence of roadway depth and creep deformation on the surrounding rock supported by 4D support is still unknown.This study investigated the influence of roadway depth and creep deformation time on the instability of surrounding rock by analyzing the energy development.The elastic strain energy was analyzed using the program redeveloped in FLAC3D.The numerical simulation results indicate that the combined support mode of 4D roof supports and conventional side supports is highly applicable to the stability control of surrounding rock with a roadway depth exceeding 520 m.With the increase of roadway depth,4D support can effectively restrain the area and depth of plastic deformation in the surrounding rock.Further,4D support limits the accumulation range and rate of elastic strain energy as the creep deformation time increases.4D support can effectively reduce the plastic deformation of roadway surrounding rock and maintain the stability for a long deformation period of 6 months.As confirmed by in situ monitoring results,4D support is more effective for the long‐term stability control of surrounding rock than conventional support. 展开更多
关键词 coal mines elastic strain energy four‐dimensional support large roadway depth long‐term stability control plastic deformation surrounding rock
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A Dimensional Reduction Approach Based on Essential Constraints in Linear Programming
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作者 Eirini I. Nikolopoulou George S. Androulakis 《American Journal of Operations Research》 2024年第1期1-31,共31页
This paper presents a new dimension reduction strategy for medium and large-scale linear programming problems. The proposed method uses a subset of the original constraints and combines two algorithms: the weighted av... This paper presents a new dimension reduction strategy for medium and large-scale linear programming problems. The proposed method uses a subset of the original constraints and combines two algorithms: the weighted average and the cosine simplex algorithm. The first approach identifies binding constraints by using the weighted average of each constraint, whereas the second algorithm is based on the cosine similarity between the vector of the objective function and the constraints. These two approaches are complementary, and when used together, they locate the essential subset of initial constraints required for solving medium and large-scale linear programming problems. After reducing the dimension of the linear programming problem using the subset of the essential constraints, the solution method can be chosen from any suitable method for linear programming. The proposed approach was applied to a set of well-known benchmarks as well as more than 2000 random medium and large-scale linear programming problems. The results are promising, indicating that the new approach contributes to the reduction of both the size of the problems and the total number of iterations required. A tree-based classification model also confirmed the need for combining the two approaches. A detailed numerical example, the general numerical results, and the statistical analysis for the decision tree procedure are presented. 展开更多
关键词 Linear Programming Binding Constraints dimension Reduction Cosine Similarity Decision Analysis Decision Trees
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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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3-Dimensional Kinematic Comparison of Arm Movements between an Individual with NGLY1 Deficiency and a Neurotypical Individual
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作者 Charles S. Layne Christopher A. Malaya +6 位作者 Brock Futrell Dacia Martinez Diaz Christian Alfaro Hannah E. Gustafson Subhalakshmi Chandrasekaran Rhea M. Phatak Bernhard Suter 《Case Reports in Clinical Medicine》 2024年第4期122-146,共25页
NGLY1 Deficiency is an ultra-rare autosomal recessively inherited disorder. Characteristic symptoms include among others, developmental delays, movement disorders, liver function abnormalities, seizures, and problems ... NGLY1 Deficiency is an ultra-rare autosomal recessively inherited disorder. Characteristic symptoms include among others, developmental delays, movement disorders, liver function abnormalities, seizures, and problems with tear formation. Movements are hyperkinetic and may include dysmetric, choreo-athetoid, myoclonic and dystonic movement elements. To date, there have been no quantitative reports describing arm movements of individuals with NGLY1 Deficiency. This report provides quantitative information about a series of arm movements performed by an individual with NGLY1 Deficiency and an aged-matched neurotypical participant. Three categories of arm movements were tested: 1) open ended reaches without specific end point targets;2) goal-directed reaches that included grasping an object;3) picking up small objects from a table placed in front of the participants. Arm movement kinematics were obtained with a camera-based motion analysis system and “initiation” and “maintenance” phases were identified for each movement. The combination of the two phases was labeled as a “complete” movement. Three-dimensional analysis techniques were used to quantify the movements and included hand trajectory pathlength, joint motion area, as well as hand trajectory and joint jerk cost. These techniques were required to fully characterize the movements because the NGLY1 individual was unable to perform movements only in the primary plane of progression instead producing motion across all three planes of movement. The individual with NGLY1 Deficiency was unable to pick up objects from a table or effectively complete movements requiring crossing the midline. The successfully completed movements were analyzed using the above techniques and the results of the two participants were compared statistically. Almost all comparisons revealed significant differences between the two participants, with a notable exception of the 3D initiation area as a percentage of the complete movement. The statistical tests of these measures revealed no significant differences between the two participants, possibly suggesting a common underlying motor control strategy. The 3D techniques used in this report effectively characterized arm movements of an individual with NGLY1 deficiency and can be used to provide information to evaluate the effectiveness of genetic, pharmacological, or physical rehabilitation therapies. 展开更多
关键词 NGLY1 Deficiency Developmental Disorders KINEMATICS 3 dimensional Analyses
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Hyper Catastrophe on 4-Dimensional Canards
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作者 Kiyoyuki Tchizawa Shuya Kanagawa 《Advances in Pure Mathematics》 2024年第4期196-203,共8页
When discovering the potential of canards flying in 4-dimensional slow-fast system with a bifurcation parameter, the key notion “symmetry” plays an important role. It is of one parameter on slow vector field. Then, ... When discovering the potential of canards flying in 4-dimensional slow-fast system with a bifurcation parameter, the key notion “symmetry” plays an important role. It is of one parameter on slow vector field. Then, it should be determined to introduce parameters to all slow/fast vectors. It is, however, there might be no way to explore for another potential in this system, because the geometrical structure is quite different from the system with one parameter. Even in this system, the “symmetry” is also useful to obtain the potentials classified by R. Thom. In this paper, via the coordinates changing, the possible way to explore for the potential will be shown. As it is analyzed on “hyper finite time line”, or done by using “non-standard analysis”, it is called “Hyper Catastrophe”. In the slow-fast system which includes a very small parameter , it is difficult to do precise analysis. Thus, it is useful to get the orbits as a singular limit. When trying to do simulations, it is also faced with difficulty due to singularity. Using very small time intervals corresponding small , we shall overcome the difficulty, because the difference equation on the small time interval adopts the standard differential equation. These small intervals are defined on hyper finite number N, which is nonstandard. As and the intervals are linked to use 1/N, the simulation should be done exactly. 展开更多
关键词 Canards Flying 4-dimensional Slow-Fast System Hyper Catastrophe
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Optimal Estimation of High-Dimensional Covariance Matrices with Missing and Noisy Data
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作者 Meiyin Wang Wanzhou Ye 《Advances in Pure Mathematics》 2024年第4期214-227,共14页
The estimation of covariance matrices is very important in many fields, such as statistics. In real applications, data are frequently influenced by high dimensions and noise. However, most relevant studies are based o... The estimation of covariance matrices is very important in many fields, such as statistics. In real applications, data are frequently influenced by high dimensions and noise. However, most relevant studies are based on complete data. This paper studies the optimal estimation of high-dimensional covariance matrices based on missing and noisy sample under the norm. First, the model with sub-Gaussian additive noise is presented. The generalized sample covariance is then modified to define a hard thresholding estimator , and the minimax upper bound is derived. After that, the minimax lower bound is derived, and it is concluded that the estimator presented in this article is rate-optimal. Finally, numerical simulation analysis is performed. The result shows that for missing samples with sub-Gaussian noise, if the true covariance matrix is sparse, the hard thresholding estimator outperforms the traditional estimate method. 展开更多
关键词 High-dimensional Covariance Matrix Missing Data Sub-Gaussian Noise Optimal Estimation
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Cosmological Model in Four Time and Four Space Dimensions
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作者 Juan Antonio Nieto 《Journal of Applied Mathematics and Physics》 2024年第3期829-840,共12页
We develop a cosmological model in a physical background scenario of four time and four space dimensions ((4+4)-dimensions or (4+4)-universe). We show that in this framework the (1+3)-universe is deeply connected with... We develop a cosmological model in a physical background scenario of four time and four space dimensions ((4+4)-dimensions or (4+4)-universe). We show that in this framework the (1+3)-universe is deeply connected with the (3+1)-universe. We argue that this means that in the (4+4)-universe there exists a duality relation between the (1+3)-universe and the (3+1)-universe. 展开更多
关键词 Cosmological Model (4+4)-dimensions Duality Symmetry
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Suppression of stimulated Raman scattering by angularly incoherent light, towards a laser system of incoherence in all dimensions of time, space, and angle 被引量:1
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作者 Yi Guo Xiaomei Zhang +3 位作者 Dirui Xu Xinju Guo Baifei Shen Ke Lan 《Matter and Radiation at Extremes》 SCIE EI CSCD 2023年第3期27-33,共7页
Laser–plasma instability(LPI)is one of the main obstacles to achieving predictable and reproducible fusion at high gain through laser-driven inertial confinement fusion(ICF).In this paper,for the first time,we show a... Laser–plasma instability(LPI)is one of the main obstacles to achieving predictable and reproducible fusion at high gain through laser-driven inertial confinement fusion(ICF).In this paper,for the first time,we show analytically and confirm with three-dimensional particle-incell simulations that angular incoherence provides suppression of the instability growth rate that is additional to and much stronger than that provided by the well-known temporal and spatial incoherence usually used in ICF studies.For the model used in our calculations,the maximum field ratio between the stimulated Raman scattering and the driving pulses drops from 0.2 for a Laguerre–Gaussian pulse with a single nonzero topological charge to 0.05 for a super light spring with an angular momentum spread and random relative phases.In particular,angular incoherence does not introduce extra undesirable hot electrons.This provides a novel method for suppressing LPI by using light with an angular momentum spread and paves the way towards a low-LPI laser system for inertial fusion energy with a super light spring of incoherence in all dimensions of time,space,and angle,and may open the door to the use of longer-wavelength lasers for inertial fusion energy. 展开更多
关键词 SCATTERING dimensionS ANGULAR
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A Dimension-Splitting Variational Multiscale Element-Free Galerkin Method for Three-Dimensional Singularly Perturbed Convection-Diffusion Problems 被引量:1
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作者 Jufeng Wang Yong Wu +1 位作者 Ying Xu Fengxin Sun 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第4期341-356,共16页
By introducing the dimensional splitting(DS)method into the multiscale interpolating element-free Galerkin(VMIEFG)method,a dimension-splitting multiscale interpolating element-free Galerkin(DS-VMIEFG)method is propose... By introducing the dimensional splitting(DS)method into the multiscale interpolating element-free Galerkin(VMIEFG)method,a dimension-splitting multiscale interpolating element-free Galerkin(DS-VMIEFG)method is proposed for three-dimensional(3D)singular perturbed convection-diffusion(SPCD)problems.In the DSVMIEFG method,the 3D problem is decomposed into a series of 2D problems by the DS method,and the discrete equations on the 2D splitting surface are obtained by the VMIEFG method.The improved interpolation-type moving least squares(IIMLS)method is used to construct shape functions in the weak form and to combine 2D discrete equations into a global system of discrete equations for the three-dimensional SPCD problems.The solved numerical example verifies the effectiveness of the method in this paper for the 3D SPCD problems.The numerical solution will gradually converge to the analytical solution with the increase in the number of nodes.For extremely small singular diffusion coefficients,the numerical solution will avoid numerical oscillation and has high computational stability. 展开更多
关键词 dimension-splitting multiscale interpolating element-free Galerkin(DS-VMIEFG)method interpolating variational multiscale element-free Galerkin(VMIEFG)method dimension splitting method singularly perturbed convection-diffusion problems
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Fluvial reservoir characterization through channel belt dimension and petrophysical analysis
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作者 Shakhawat Hossain Tahmidur Rahman Junayed Naymur Rahman 《Petroleum Science》 SCIE EI CAS CSCD 2023年第2期787-802,共16页
The dimensions and connectivity of fluvial reservoirs vary greatly, making it challenging to characterize them using conventional approaches. In this study integrated channel belt dimension analysis from seismic geomo... The dimensions and connectivity of fluvial reservoirs vary greatly, making it challenging to characterize them using conventional approaches. In this study integrated channel belt dimension analysis from seismic geomorphology and empirical equations, well log facies, and petrophysical analysis were performed to characterize the fluvial reservoirs. The study interval consists of fluvial deposits and is divided into three reservoir zones, which are defined by four key regional markers (B, D, K, O). In these intervals, six (6) fluvial facies have been identified. Based on the log facies proportions and their stacking relationships, it is interpreted that the reservoirs in zone 1 (B to D) were deposited in a proximal reach of a meandering system, zone 2 (D to K) in a marginal marine setting, and zone 3 (K) in a distal reach of a meandering system. The dimensions of fluvial channels and channel belts were determined using empirical equations. The results were compared with the observed dimensions of fluvial channels and channel belts from the seismic horizon and stratal slices of the same intervals. Zones 1 and 3 are characterized by broad meander belts (1000–4000 m) compared to zone 2 (600–1300 m). Petrophysical analysis showed zones 1 and 3 have the better petrophysical properties compared to zone 2. Though zone 3 has the most well-developed sand bodies, the best reservoir interval is zone 1 because of its higher porosity. Although channel belt dimensions have a significant influence on reservoir connectivity, they do not seem to have control on reservoir properties. The channel belt dimensions obtained from the empirical equations and interpreted from the seismic geomorphology analysis were found to be strikingly similar. Since three-dimensional seismic data is not available everywhere and seismic imaging quality decreases with depth, empirical equations can be used to analyze fluvial reservoir parameters and their connectivity at greater depths. 展开更多
关键词 Log motif FLUVIAL Channel belt dimension Seismic geomorphology PETROPHYSICS Moragot field
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ON THE GRAPHS OF PRODUCTS OF CONTINUOUS FUNCTIONS AND FRACTAL DIMENSIONS
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作者 刘佳 石赛赛 张远 《Acta Mathematica Scientia》 SCIE CSCD 2023年第6期2483-2492,共10页
In this paper,we consider the graph of the product of continuous functions in terms of Hausdorff and packing dimensions.More precisely,we show that,given a real number 1≤β≤2,any real-valued continuous function in C... In this paper,we consider the graph of the product of continuous functions in terms of Hausdorff and packing dimensions.More precisely,we show that,given a real number 1≤β≤2,any real-valued continuous function in C([0,1])can be decomposed into a product of two real-valued continuous functions,each having a graph of Hausdorff dimensionβ.In addition,a product decomposition result for the packing dimension is obtained.This work answers affirmatively two questions raised by Verma and Priyadarshi[14]. 展开更多
关键词 Hausdorff dimension packing dimension graph of function product of functions
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A New Dynamics Analysis Model for Five-Axis Machining of Curved Surface Based on Dimension Reduction and Mapping
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作者 Minglong Guo Zhaocheng Wei +2 位作者 Minjie Wang Zhiwei Zhao Shengxian Liu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2023年第6期172-184,共13页
The equipment used in various fields contains an increasing number of parts with curved surfaces of increasing size.Five-axis computer numerical control(CNC)milling is the main parts machining method,while dynamics an... The equipment used in various fields contains an increasing number of parts with curved surfaces of increasing size.Five-axis computer numerical control(CNC)milling is the main parts machining method,while dynamics analysis has always been a research hotspot.The cutting conditions determined by the cutter axis,tool path,and workpiece geometry are complex and changeable,which has made dynamics research a major challenge.For this reason,this paper introduces the innovative idea of applying dimension reduction and mapping to the five-axis machining of curved surfaces,and proposes an efficient dynamics analysis model.To simplify the research object,the cutter position points along the tool path were discretized into inclined plane five-axis machining.The cutter dip angle and feed deflection angle were used to define the spatial position relationship in five-axis machining.These were then taken as the new base variables to construct an abstract two-dimensional space and establish the mapping relationship between the cutter position point and space point sets to further simplify the dimensions of the research object.Based on the in-cut cutting edge solved by the space limitation method,the dynamics of the inclined plane five-axis machining unit were studied,and the results were uniformly stored in the abstract space to produce a database.Finally,the prediction of the milling force and vibration state along the tool path became a data extraction process that significantly improved efficiency.Two experiments were also conducted which proved the accuracy and efficiency of the proposed dynamics analysis model.This study has great potential for the online synchronization of intelligent machining of large surfaces. 展开更多
关键词 Curved surface Five-axis machining dimension reduction and mapping Milling force DYNAMICS
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Bounds on Fractional-Based Metric Dimension of Petersen Networks
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作者 Dalal Awadh Alrowaili Mohsin Raza Muhammad Javaid 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第6期2697-2713,共17页
The problem of investigating the minimum set of landmarks consisting of auto-machines(Robots)in a connected network is studied with the concept of location number ormetric dimension of this network.In this paper,we st... The problem of investigating the minimum set of landmarks consisting of auto-machines(Robots)in a connected network is studied with the concept of location number ormetric dimension of this network.In this paper,we study the latest type of metric dimension called as local fractional metric dimension(LFMD)and find its upper bounds for generalized Petersen networks GP(n,3),where n≥7.For n≥9.The limiting values of LFMD for GP(n,3)are also obtained as 1(bounded)if n approaches to infinity. 展开更多
关键词 Metric dimension local fractional metric dimension Petersen network local resolving neighborhoods
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Metric Basis of Four-Dimensional Klein Bottle
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作者 Ali N.A.Koam Ali Ahmad +2 位作者 Maryam Salem Alatawi Muhammad Azeem Muhammad Faisal Nadeem 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第9期3011-3024,共14页
The Metric of a graph plays an essential role in the arrangement of different dimensional structures and finding their basis in various terms.The metric dimension of a graph is the selection of the minimum possible nu... The Metric of a graph plays an essential role in the arrangement of different dimensional structures and finding their basis in various terms.The metric dimension of a graph is the selection of the minimum possible number of vertices so that each vertex of the graph is distinctively defined by its vector of distances to the set of selected vertices.This set of selected vertices is known as the metric basis of a graph.In applied mathematics or computer science,the topic of metric basis is considered as locating number or locating set,and it has applications in robot navigation and finding a beacon set of a computer network.Due to the vast applications of this concept in computer science,optimization problems,and also in chemistry enormous research has been conducted.To extend this research to a four-dimensional structure,we studied the metric basis of the Klein bottle and proved that the Klein bottle has a constant metric dimension for the variation of all its parameters.Although the metric basis is variying in 3 and 4 values when the values of its parameter change,it remains constant and unchanged concerning its order or number of vertices.The methodology of determining the metric basis or locating set is based on the distances of a graph.Therefore,we proved the main theorems in distance forms. 展开更多
关键词 Klein bottle metric basis resolving set metric dimension
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RELATIVE ENTROPY DIMENSION FOR COUNTABLE AMENABLE GROUP ACTIONS
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作者 肖祖彪 殷正宇 《Acta Mathematica Scientia》 SCIE CSCD 2023年第6期2430-2448,共19页
We study the topological complexities of relative entropy zero extensions acted upon by countable-infinite amenable groups.First,for a given Følner sequence,we define the relative entropy dimensions and the dimen... We study the topological complexities of relative entropy zero extensions acted upon by countable-infinite amenable groups.First,for a given Følner sequence,we define the relative entropy dimensions and the dimensions of the relative entropy generating sets to characterize the sub-exponential growth of the relative topological complexity.we also investigate the relations among these.Second,we introduce the notion of a relative dimension set.Moreover,using the method,we discuss the disjointness between the relative entropy zero extensions via the relative dimension sets of two extensions,which says that if the relative dimension sets of two extensions are different,then the extensions are disjoint. 展开更多
关键词 amenable groups relative entropy dimensions relative dimension sets
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Active-passive radial-additive friction stir repairing of mechanical hole out of dimension tolerance of AZ31 magnesium alloy
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作者 Hua Liu Zhenlei Liu +3 位作者 Shude Ji Yumei Yue Zhibo Dong Changlong Chen 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2023年第9期3186-3199,共14页
In order to avoid the depth increasing of repaired hole and eliminate the super-fine grain band in stir zone by radial-additive friction stir repairing(R-AFSR), a solid-state repairing technique of active-passive radi... In order to avoid the depth increasing of repaired hole and eliminate the super-fine grain band in stir zone by radial-additive friction stir repairing(R-AFSR), a solid-state repairing technique of active-passive radial-additive friction stir repairing(AP-RAFSR) assisted by the truncated cone-shaped filling material was proposed in this study. The mechanical hole out of dimension tolerance of AZ31 magnesium alloy was chosen as the repaired object. The results indicated that the AP-RAFSR process rather than the R-AFSR process avoided the kissing bond in the bottom of the repairing interface under the condition of the tool pin length equal to the height of the standard mechanical hole.The continuously-distributed and large-length super-fine grain bands were eliminated in the stir zone by AP-RAFSR. The maximum tensile and compressive-shear strengths of repaired hole by AP-RAFSR reached 190.6 MPa and 138.9 MPa at 1200 rpm respectively, which were equivalent to 97.7% and 89.6% of those of the standard mechanical hole. This AP-RAFSR process assisted by the truncated cone-shaped filling material provides a new technique to obtain a no-depth-increasing, defect-free and high-strength repaired mechanical hole. 展开更多
关键词 Active-passive radial-additive friction stir repairing Mechanical hole out of dimension tolerance Numerical simulation Microstructure Mechanical properties
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Early selection efficiency for fiber dimensions and their relationships with growth and wood quality for Pinus elliotth Engelm.in southern China
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作者 Jing Wen Min Yi +5 位作者 Leiming Dong Lu Zhang Siyu Liu Shenggui Yuan Xiaoxiao Tao Meng Lai 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第6期1951-1962,共12页
A solid understanding of the efficiency of early selection for fiber dimensions is a prerequisite for breeding slash pine(Pinus elliottii Engelm.)with improved properties for pulp and paper products.Genetic correlatio... A solid understanding of the efficiency of early selection for fiber dimensions is a prerequisite for breeding slash pine(Pinus elliottii Engelm.)with improved properties for pulp and paper products.Genetic correlations between size of fibers,wood quality and growth properties are also important.To accomplish effective early selection for size of fibers and evaluate the impact for wood quality traits and ring widths,core samples were collected from360 trees of 20 open-pollinated Pinus elliottii families from three genetic trials.Cores were measured by SilviScan,and the age trends for phenotypic values,heritability,early-late genetic correlations,and early selection efficiency for fiber dimensions,such as tangential and radial fiber widths,fiber wall thickness and fiber coarseness,and their correlations with microfibril angle(MFA),modulus of elasticity(MOE),wood density and ring width were investigated.Different phenotypic trends were found for tangential and radial fiber widths while fiber coarseness and wall thickness curves were similar.Age trends of heritability based on area-weighted fiber dimensions were different.Low to moderate heritability from pith to bark(~0.5)was found for all fiber dimension across the three sites except for tangential fiber width and wall thickness at the Ganzhou site.Early-late genetic correlations were 0.9 after age of 9 years,and early selection for fiber dimensions could be effective due to strong genetic correlations.Our results showed moderate to strong positive genetic correlations for modulus of elasticity and density with fiber dimensions.The effects on fiber dimensions were weak or moderate when ring width or wood quality traits were selected alone.Estimates of efficiency for early selection indicated that the optimal age for radial fiber width and fiber coarseness was 6-7 years,while for tangential fiber width and wall thickness was 9-10 years. 展开更多
关键词 Pinus elliottii Early selection efficiency Genetic correlation HERITABILITY Fiber dimensions
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