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Euler’s First-Order Explicit Method–Peridynamic Differential Operator for Solving Population Balance Equations of the Crystallization Process
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作者 Chunlei Ruan Cengceng Dong +2 位作者 Kunfeng Liang Zhijun Liu Xinru Bao 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第3期3033-3049,共17页
Using Euler’s first-order explicit(EE)method and the peridynamic differential operator(PDDO)to discretize the time and internal crystal-size derivatives,respectively,the Euler’s first-order explicit method–peridyna... Using Euler’s first-order explicit(EE)method and the peridynamic differential operator(PDDO)to discretize the time and internal crystal-size derivatives,respectively,the Euler’s first-order explicit method–peridynamic differential operator(EE–PDDO)was obtained for solving the one-dimensional population balance equation in crystallization.Four different conditions during crystallization were studied:size-independent growth,sizedependent growth in a batch process,nucleation and size-independent growth,and nucleation and size-dependent growth in a continuous process.The high accuracy of the EE–PDDO method was confirmed by comparing it with the numerical results obtained using the second-order upwind and HR-van methods.The method is characterized by non-oscillation and high accuracy,especially in the discontinuous and sharp crystal size distribution.The stability of the EE–PDDO method,choice of weight function in the PDDO method,and optimal time step are also discussed. 展开更多
关键词 Population balance equation CRYsTALLIZATION peridynamic differential operator Euler’s first-order explicit method
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融合改进Dijkstra算法和动态窗口法的移动机器人路径规划
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作者 郭建 杨朋 +2 位作者 曾志豪 黄颖驹 王家淳 《组合机床与自动化加工技术》 北大核心 2024年第3期36-40,共5页
为解决移动机器人在智能制造车间的全局路径规划和局部动态避障问题,提出一种融合改进的Dijkstra算法和改进的DWA算法,对传统Dijkstra算法的路径进行平滑优化,使得路径轨迹更加平滑,动态改变DWA算法中速度评价权重函数,提高避障效率。... 为解决移动机器人在智能制造车间的全局路径规划和局部动态避障问题,提出一种融合改进的Dijkstra算法和改进的DWA算法,对传统Dijkstra算法的路径进行平滑优化,使得路径轨迹更加平滑,动态改变DWA算法中速度评价权重函数,提高避障效率。仿真结果表明,改进Dijkstra算法路径平滑优化后,平均路程缩短比例为0.65%,平均偏航角震荡次数减少了67.70%,改进后的DWA算法运行路程缩小9.68%,路径转折次数降低了33%,运行时间缩短3.88%。基于改进的Dijkstra算法和改进的DWA算法提出一种融合算法,仿真和样机实验结果表明:面对静态、动态障碍物,机器人运行线速度平缓,轨迹光滑,角速度波动明显,证明机器人运动稳定,实时调整方位,具有良好的避障能力。并且多次机器人循环定点实验中机器人纵向(X轴方向)平均误差≤30 mm,横向(Y轴)平均误差≤30 mm,定位精度满足工业需求。 展开更多
关键词 dijkstra算法 动态窗口法 移动机器人路径规划 实时避障
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基于层次决策模型和改进Dijkstra算法的地下停车场车辆引导方法研究
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作者 郑英 张立珍 +2 位作者 郁佳佳 谢修娟 黄丽薇 《广东交通职业技术学院学报》 2023年第3期61-65,共5页
本文提出一种用户层次决策和改进Dijkstra引导相结合的地下停车场车位引导方法。首先采用改进Dijkstra算法搜索距离电梯口的距离最近的3个车位供用户选择;然后根据用户对停车位需求,采用层次化决策方法选出满足需求的目标停车位;最后采... 本文提出一种用户层次决策和改进Dijkstra引导相结合的地下停车场车位引导方法。首先采用改进Dijkstra算法搜索距离电梯口的距离最近的3个车位供用户选择;然后根据用户对停车位需求,采用层次化决策方法选出满足需求的目标停车位;最后采用Dijkstra算法,将车辆按照最短路径的方法引导到目标停车位。仿真结果表明,该引导方法实现了让用户根据需求参与选择最短路径的目标停车位,并将车辆从地下停车场入口引导到目标停车位,不仅减少了搜索车位数量和引导路径,提高了停车效率,而且实现了停车场车位引导的智能化和人性化。 展开更多
关键词 层次决策 车辆引导方法 dijkstra算法
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Contribution to the Improvement of the Petroleum Products Delivery Policy by the Implementation of a Computer System Based on the Dijkstra Method
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作者 Richard Kangiama Lwangi Bavon Diemu Tshiband +7 位作者 Patrick Bokungu Efoto Alfred Mukuna Jean Ondontshia Nkoyi Jean-Pierre Kalay Kut Bruno Deko Oyema Benjamin Safari Kachunga Bigohe Nzana Rwubaka Dady Stephane Ilunga Nyembwe 《Journal of Computer and Communications》 2022年第3期1-9,共9页
The distribution and marketing of petroleum products are the sources of energy for the various activities of human society and household supply. We spent our time researching the competitive factors to reduce the time... The distribution and marketing of petroleum products are the sources of energy for the various activities of human society and household supply. We spent our time researching the competitive factors to reduce the time of distribution of petroleum products, by setting up a computer system based on Dijkstra’s algorithm our contribution will solve a real problem of delivery with direct targeting of gas stations. We set up a tool to help to map based on the method of operational research starting with the identification of delivery point, mapping and then applying the algorithm. Mainly the graph theory and the optimal path in a network by a short path using the method of Dijkstra for the design we used the UML language, the programming we used the JAVA language with very appreciable results to finish with a conclusion. 展开更多
关键词 Community Operations Research dijkstra’s method Oil Tankers Graph Theory Computer systems Industrial Engineering sEP-Congo
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电液3-UPS/S并联稳定平台参数振动特性分析
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作者 袁晓明 王维锜 +1 位作者 庞浩东 张立杰 《振动与冲击》 EI CSCD 北大核心 2024年第5期52-61,共10页
针对电液3-UPS/S并联稳定平台驱动液压缸的压力脉动所产生的参数振动,建立了稳定平台的参数振动方程并利用多尺度法求解了主共振响应与组合共振响应的一次近似解;分析了主共振与组合共振响应特性以及振动幅值在初始工作空间内的变化规律... 针对电液3-UPS/S并联稳定平台驱动液压缸的压力脉动所产生的参数振动,建立了稳定平台的参数振动方程并利用多尺度法求解了主共振响应与组合共振响应的一次近似解;分析了主共振与组合共振响应特性以及振动幅值在初始工作空间内的变化规律,最后采用四阶龙格库塔法与模态试验对参数振动模型进行验证。结果表明:数值解与理论解之间的最大误差为4.20%,固有频率理论值与试验值之间的最大误差为4.66%,可验证参数振动模型的正确性。 展开更多
关键词 电液3-UPs/s并联稳定平台 压力脉动 参数振动 多尺度法 振动特性
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基于改进Dijkstra算法的仓储拣选最优路径规划研究 被引量:1
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作者 余宝意 李乐 石德伦 《无线互联科技》 2023年第10期147-149,共3页
Dijkstra(迪科斯彻)算法是典型的单源最短路径算法,用于计算一个节点到其他所有节点的最短路径,其主要特点是以起始点为中心向外层层扩展,直到扩展到终点为止。Dijkstra算法是很有代表性的最短路径算法。文章研究了叉车在仓储作业选择... Dijkstra(迪科斯彻)算法是典型的单源最短路径算法,用于计算一个节点到其他所有节点的最短路径,其主要特点是以起始点为中心向外层层扩展,直到扩展到终点为止。Dijkstra算法是很有代表性的最短路径算法。文章研究了叉车在仓储作业选择最优路径的问题,主要根据仓储巷道交通网络数据,建立数学模型,确定叉车仓储作业的最优路径,并且对模型的优缺点进行分析,提出改进方法,以更好地研究叉车仓储作业的最优路径选择问题。本研究选出在仓储巷道作业车辆从起点到终点的最优路径。结果表明,Dijkstra算法能够计算出车辆作业的最优线路,对现场的司机指导、工作效率提高提供了很好的支持。 展开更多
关键词 加权平均法 迪杰斯彻算法 最优路径
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基于D-S证据理论改进AHP-熵权的流域洪涝灾害评估研究
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作者 苑希民 高瑞梅 +1 位作者 田福昌 侯玮 《水资源与水工程学报》 CSCD 北大核心 2024年第1期9-16,共8页
考虑致灾因子危险性、孕灾环境敏感性以及承灾体易损性,选取指标构建小清河流域洪涝灾害风险评估指标体系,提出一种基于D-S证据理论的改进AHP-熵权法计算指标权重,求取洪涝灾害风险指数,运用自然断点分级法确定洪涝灾害风险等级,分析小... 考虑致灾因子危险性、孕灾环境敏感性以及承灾体易损性,选取指标构建小清河流域洪涝灾害风险评估指标体系,提出一种基于D-S证据理论的改进AHP-熵权法计算指标权重,求取洪涝灾害风险指数,运用自然断点分级法确定洪涝灾害风险等级,分析小清河流域洪涝灾害风险空间分布情况。结果表明:小清河流域洪涝灾害风险总体上表现出南低北高的趋势,其中高风险区和较高风险区分别占流域面积的8.7%和14.3%,主要分布在小清河干流以及主要支流两岸。所得评估结果同“利奇马”台风发生期间实际洪灾风险分布情况一致,对比证明基于D-S证据理论的改进AHP-熵权法优于AHP和熵权法,可为小清河流域防洪减灾决策提供依据。 展开更多
关键词 D-s证据理论 AHP 熵权法 洪涝灾害评估 小清河流域
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基于Dijkstra算法的电力光通信网络智能运维设备脱网故障区段定位方法 被引量:2
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作者 张海龙 李博 贾娜娟 《电信科学》 2023年第1期92-99,共8页
智能运维设备发生脱网故障后,往往难以定位,为实现脱网故障区段与故障电流分布间映射关系的确定、寻找脱网故障区段与故障电流分布间映射关系的最短路径,设计一种基于Dijkstra算法的电力光通信网络智能运维设备脱网故障区段定位方法。... 智能运维设备发生脱网故障后,往往难以定位,为实现脱网故障区段与故障电流分布间映射关系的确定、寻找脱网故障区段与故障电流分布间映射关系的最短路径,设计一种基于Dijkstra算法的电力光通信网络智能运维设备脱网故障区段定位方法。选择数据驱动方法中的LightGBM算法,通过大量样本确定离网故障区段与故障电流分布之间的映射关系。基于Dijkstra算法寻找映射关系的最短路径,实施脱网故障区段搜索。设计电力光通信网络智能运维设备脱网故障区段定位平台,实现脱网故障点即智能运维设备信号丢失的定位与告警。对比实验显示,在SDH环网电路区域中的光缆中断导致的脱网故障区段定位、多路由段的光缆故障下的脱网故障区段定位,以及在环状电力区域中的多路由段的光缆故障下的脱网故障区段定位场景中,该方法的定位结果与实际位置最贴近,定位最准确。 展开更多
关键词 dijkstra算法 电力光通信网络 数据驱动方法 智能运维设备 IBFA算法 脱网故障区段定位
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On the Approximation of Fractal-Fractional Differential Equations Using Numerical Inverse Laplace Transform Methods
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作者 Kamran Siraj Ahmad +2 位作者 Kamal Shah Thabet Abdeljawad Bahaaeldin Abdalla 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第6期2743-2765,共23页
Laplace transform is one of the powerful tools for solving differential equations in engineering and other science subjects.Using the Laplace transform for solving differential equations,however,sometimes leads to sol... Laplace transform is one of the powerful tools for solving differential equations in engineering and other science subjects.Using the Laplace transform for solving differential equations,however,sometimes leads to solutions in the Laplace domain that are not readily invertible to the real domain by analyticalmeans.Thus,we need numerical inversionmethods to convert the obtained solution fromLaplace domain to a real domain.In this paper,we propose a numerical scheme based on Laplace transform and numerical inverse Laplace transform for the approximate solution of fractal-fractional differential equations with orderα,β.Our proposed numerical scheme is based on three main steps.First,we convert the given fractal-fractional differential equation to fractional-differential equation in Riemann-Liouville sense,and then into Caputo sense.Secondly,we transformthe fractional differential equation in Caputo sense to an equivalent equation in Laplace space.Then the solution of the transformed equation is obtained in Laplace domain.Finally,the solution is converted into the real domain using numerical inversion of Laplace transform.Three inversion methods are evaluated in this paper,and their convergence is also discussed.Three test problems are used to validate the inversion methods.We demonstrate our results with the help of tables and figures.The obtained results show that Euler’s and Talbot’s methods performed better than Stehfest’s method. 展开更多
关键词 Fractal-fractional differential equation power law kernel exponential decay kernel Mittag-Leffler kernel Laplace transform Euler’s method Talbot’s method stehfest’s method
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Route Search Method for Railway Replacement Buses Adopting Ant Colony Optimization
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作者 Kei Nagaoka Kayoko Yamamoto 《Journal of Geographic Information System》 2023年第4期391-420,共30页
In recent years, Japan, and especially rural areas have faced the growing problems of debt-ridden local railway lines along with the population decline and aging population. Therefore, it is best to consider the disco... In recent years, Japan, and especially rural areas have faced the growing problems of debt-ridden local railway lines along with the population decline and aging population. Therefore, it is best to consider the discontinuation of local railway lines and introduce replacement buses to secure the transportation methods of the local people especially in rural areas. Based on the above background, targeting local railway lines that may be discontinued in the near future, appropriate bus stops when provided with potential bus stops were selected, the present study proposed a method that introduces routes for railway replacement buses adopting ant colony optimization (ACO). The improved ACO was designed and developed based on the requirements set concerning the route length, number of turns, road width, accessibility of railway lines and zones without bus stops as well as the constraint conditions concerning the route length, number of turns and zones without bus stops. Original road network data were generated and processed adopting a geographic information systems (GIS), and these are used to search for the optimal route for railway replacement buses adopting the improved ACO concerning the 8 zones on the target railway line (JR Kakogawa line). By comparing the improved ACO with Dijkstra’s algorithm, its relevance was verified and areas needing further improvements were revealed. 展开更多
关键词 Local Railway Line Railway Replacement Bus Route search method Ant Colony Optimization (ACO) dijkstra’s Algorithm Geographic Information systems (GIs)
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Continuum Skyrme Hartree-Fock-Bogoliubov theory with Green’s function method for neutron-rich Ca,Ni,Zr,and Sn isotopes
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作者 En-Bo Huo Ke-Ran Li +2 位作者 Xiao-Ying Qu Ying Zhang Ting-Ting Sun 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第7期162-178,共17页
The possible exotic nuclear properties in the neutron-rich Ca,Ni,Zr,and Sn isotopes are examined with the continuum Skyrme Hartree-Fock-Bogoliubov theory in the framework of the Green’s function method.The pairing co... The possible exotic nuclear properties in the neutron-rich Ca,Ni,Zr,and Sn isotopes are examined with the continuum Skyrme Hartree-Fock-Bogoliubov theory in the framework of the Green’s function method.The pairing correlation,the couplings with the continuum,and the blocking effects for the unpaired nucleon in odd-A nuclei are properly treated.The Skyrme interaction SLy4 is adopted for the ph channel and the density-dependentinteraction is adopted for the pp chan-nel,which well reproduce the experimental two-neutron separation energies S_(2n)and one-neutron separation energies Sn.It is found that the criterion S_(n)>0 predicts a neutron drip line with neutron numbers much smaller than those for S_(2n)>0.Owing to the unpaired odd neutron,the neutron pairing energies−E_(pair)in odd-A nuclei are much lower than those in the neighbor-ing even-even nuclei.By investigating the single-particle structures,the possible halo structures in the neutron-rich Ca,Ni,and Sn isotopes are predicted,where sharp increases in the root-mean-square(rms)radii with significant deviations from the traditional rA^(1∕3)rule and diffuse spatial density distributions are observed.Analyzing the contributions of various partial waves to the total neutron densityρlj(r)∕ρ(r)reveals that the orbitals located around the Fermi surface-particularly those with small angular momenta-significantly affect the extended nuclear density and large rms radii.The number of neutrons Nλ(N_(0))occupying above the Fermi surfacen(continuum threshold)is discussed,whose evolution as a function of the mass number A in each isotope is consistent with that of the pairing energy,supporting the key role of the pairing correlation in halo phenomena. 展开更多
关键词 Neutron-rich nuclei Neutron halo skyrme Hartree-Fock-Bogoliubov theory Green’s function method
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Stochastic Programming for Hub Energy Management Considering Uncertainty Using Two-Point Estimate Method and Optimization Algorithm
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作者 Ali S.Alghamdi Mohana Alanazi +4 位作者 Abdulaziz Alanazi Yazeed Qasaymeh Muhammad Zubair Ahmed Bilal Awan M.G.B.Ashiq 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第12期2163-2192,共30页
To maximize energy profit with the participation of electricity,natural gas,and district heating networks in the day-ahead market,stochastic scheduling of energy hubs taking into account the uncertainty of photovoltai... To maximize energy profit with the participation of electricity,natural gas,and district heating networks in the day-ahead market,stochastic scheduling of energy hubs taking into account the uncertainty of photovoltaic and wind resources,has been carried out.This has been done using a new meta-heuristic algorithm,improved artificial rabbits optimization(IARO).In this study,the uncertainty of solar and wind energy sources is modeled using Hang’s two-point estimating method(TPEM).The IARO algorithm is applied to calculate the best capacity of hub energy equipment,such as solar and wind renewable energy sources,combined heat and power(CHP)systems,steamboilers,energy storage,and electric cars in the day-aheadmarket.The standard ARO algorithmis developed to mimic the foraging behavior of rabbits,and in this work,the algorithm’s effectiveness in avoiding premature convergence is improved by using the dystudynamic inertia weight technique.The proposed IARO-based scheduling framework’s performance is evaluated against that of traditional ARO,particle swarm optimization(PSO),and salp swarm algorithm(SSA).The findings show that,in comparison to previous approaches,the suggested meta-heuristic scheduling framework based on the IARO has increased energy profit in day-ahead electricity,gas,and heating markets by satisfying the operational and energy hub limitations.Additionally,the results show that TPEM approach dependability consideration decreased hub energy’s profit by 8.995%as compared to deterministic planning. 展开更多
关键词 stochastic energy hub scheduling energy profit UNCERTAINTY Hong’s two-point estimate method improved artificial rabbits optimization
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Establishment of Molecular Biological Method for Identification of Bacteria by 16S rDNA and gyrB Gene
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作者 Xiaxia HOU Yunxia WANG +1 位作者 Cuizhi LI Zhiyong LU 《Asian Agricultural Research》 2023年第4期21-25,共5页
[Objectives]The paper was to establish a molecular biological method for identification of bacterial strains.[Methods]The thalli of standard bacterial strains existing in the laboratory were collected and genomic DNA ... [Objectives]The paper was to establish a molecular biological method for identification of bacterial strains.[Methods]The thalli of standard bacterial strains existing in the laboratory were collected and genomic DNA was extracted for amplification of 16S rDNA and gyrB gene.The 16S rDNA and gyrB gene sequences were obtained after sequencing.Sequences were aligned and analyzed via EzBioCloud and NCBI database,and phylogenetic trees were constructed to determine the species relationship of strains.Meantime,they were compared with known strains.[Results]This method could identify 5 standard strains accurately to the species level.The 16S rDNA and gyrB gene sequences were aligned and analyzed in EzBioCloud database and NCBI database.The strain with the max score was consistent with the known strain.And the query cover and ident were both above 99%.[Conclusions]The established molecular biological method for identification of bacterial strains by 16S rDNA and gyrB gene has good accuracy,which effectively solves the problem that the laboratory identification of bacteria relies on traditional methods and the accuracy can not be guaranteed,and further improves the identification ability of laboratory bacterial strains. 展开更多
关键词 16s rDNA GYRB Bacterial identification Molecular biological method
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Model test of negative Poisson’s ratio cable for supporting super-largespan tunnel using excavation compensation method
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作者 Manchao He Aipeng Guo +4 位作者 Zhifeng Du Songyuan Liu Chun Zhu Shiding Cao Zhigang Tao 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第6期1355-1369,共15页
In recent years,there is a scenario in urban tunnel constructions to build super-large-span tunnels for traffic diversion and route optimization purposes.However,the increased size makes tunnel support more difficult.... In recent years,there is a scenario in urban tunnel constructions to build super-large-span tunnels for traffic diversion and route optimization purposes.However,the increased size makes tunnel support more difficult.Unfortunately,there are few studies on the failure and support mechanism of the surrounding rocks in the excavation of supported tunnel,while most model tests of super-large-span tunnels focus on the failure characteristics of surrounding rocks in tunnel excavation without supports.Based on excavation compensation method(ECM),model tests of a super-large-span tunnel excavation by different anchor cable support methods in the initial support stage were carried out.The results indicate that during excavation of super-large-span tunnel,the stress and displacement of the shallow surrounding rocks decrease,following a step-shape pattern,and the tunnel failure is mainly concentrated on the vault and spandrel areas.Compared with conventional anchor cable supports,the NPR(negative Poisson’s ratio)anchor cable support is more suitable for the initial support stage of the super-large-span tunnels.The tunnel support theory,model test materials,methods,and the results obtained in this study could provide references for study of similar super-large-span tunnels。 展开更多
关键词 super-large-span tunnel Excavation compensation method(ECM) NPR(Negative Poisson’s ratio)anchor cable Model test
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Adomian Modification Methods for the Solution of Chebyshev’s Differential Equations
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作者 Mariam Al Mazmumy Aishah Alsulami +1 位作者 Huda Bakodah Nawal Alzaid 《Applied Mathematics》 2023年第8期512-530,共19页
The current study examines the important class of Chebyshev’s differential equations via the application of the efficient Adomian Decomposition Method (ADM) and its modifications. We have proved the effectiveness of ... The current study examines the important class of Chebyshev’s differential equations via the application of the efficient Adomian Decomposition Method (ADM) and its modifications. We have proved the effectiveness of the employed methods by acquiring exact analytical solutions for the governing equations in most cases;while minimal noisy error terms have been observed in a particular method modification. Above all, the presented approaches have rightly affirmed the exactitude of the available literature. More to the point, the application of this methodology could be extended to examine various forms of high-order differential equations, as approximate exact solutions are rapidly attained with less computation stress. 展开更多
关键词 ADM Modifications methods Chebyshev’s Differential Equations IVPs series solutions
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Solution of Laguerre’s Differential Equations via Modified Adomian Decomposition Method
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作者 Mariam Al-Mazmumy Aishah A. Alsulami 《Journal of Applied Mathematics and Physics》 2023年第1期85-100,共16页
This paper presents a technique for obtaining an exact solution for the well-known Laguerre’s differential equations that arise in the modeling of several phenomena in quantum mechanics and engineering. We utilize an... This paper presents a technique for obtaining an exact solution for the well-known Laguerre’s differential equations that arise in the modeling of several phenomena in quantum mechanics and engineering. We utilize an efficient procedure based on the modified Adomian decomposition method to obtain closed-form solutions of the Laguerre’s and the associated Laguerre’s differential equations. The proposed technique makes sense as the attitudes of the acquired solutions towards the neighboring singular points are correctly taken care of. 展开更多
关键词 Modification method singular Ordinary Differential Equations Laguerre’s Equation Associated Laguerre’s Equation
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基于S-CAD法的县域新型城镇化发展规划方案评估研究——以陕西省佳县为例
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作者 付晓萌 张沛 +1 位作者 杨保琨 王娜 《西部人居环境学刊》 CSCD 北大核心 2024年第1期115-121,共7页
规划方案作为相关利益主体价值观的直接体现,应当在规划评估中予以重视。基于城乡规划的公共政策属性,采用S-CAD政策评估方法,以陕西省佳县的《新型城镇化与城乡统筹规划》文本为例,选取规划编制与实施主体——政府作为主导视角,对规划... 规划方案作为相关利益主体价值观的直接体现,应当在规划评估中予以重视。基于城乡规划的公共政策属性,采用S-CAD政策评估方法,以陕西省佳县的《新型城镇化与城乡统筹规划》文本为例,选取规划编制与实施主体——政府作为主导视角,对规划文本的内容进行解构,在此基础上进行规划立场、目标、手段与预期结果的一致性、充要性与依赖性分析。研究发现:一、该规划文本自身的逻辑性较强,各个环节存在基本的对应关系;二、规划文本当中对于产业发展以及由此带来的人口问题、基础设施与公共服务设施问题的解决方案描述较多,对于生态环境保护、交通环境改善以及人口流动的实质性解决方案相对较少,逻辑上存在一定的漏洞,需进一步完善逻辑链条。基于此,提出建立城乡规划全过程评估体系及重视多元利益主体协调关系的建议,以期为相关规划的编制与评估工作提供参考。 展开更多
关键词 s-CAD政策评估方法 县域城镇化 新型城镇化 城乡统筹 文本评估
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Synthesis of Al2S3/MoS2 Nanocomposite by Electrochemical Method: Correlation for Photodegradation of Trichloroacetic Acid, Chloroacetic Acid, Acetic Acid and Study of Antibacterial Efficiency
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作者 Hiremarali Sathyanarayana Sindhushree Kodenakoppalu Mahadevappa Chaithra +1 位作者 Rayapura Thimmegowda Radhika Bellale Marigowda Venkatesha 《Modern Research in Catalysis》 2023年第1期1-24,共24页
Al<sub>2</sub>S<sub>3</sub>/MoS<sub>2</sub> nanocomposite has been synthesized through electrochemical method and characterized by UV-Visible spectroscopy, XRD, SEM and EDAX data. U... Al<sub>2</sub>S<sub>3</sub>/MoS<sub>2</sub> nanocomposite has been synthesized through electrochemical method and characterized by UV-Visible spectroscopy, XRD, SEM and EDAX data. UV-Visible spectroscopy measurements reveal that the Al<sub>2</sub>S<sub>3</sub>/MoS<sub>2</sub> nanocomposite has maximum absorption at 353.04 nm and this peak position reflects the band gap of particles and it is found to be 2.51 eV which was calculated using Tauc plot. X-Ray diffraction (XRD) reveals crystaline size to be 49.85 nm which was calculated using Williamson-Hall (W-H) plot method. Photocatalytic degradation of acetic acid, chloroacetic acid and trichloroacetic acid has been studied by volumetric method using NaOH solution. Photocatalytic degradation of chloroacetic acid and acetic acid follows first order kinetics. The photodegradation efficiency for Al<sub>2</sub>S<sub>3</sub>/MoS<sub>2</sub> nanocomposite was found to be ≈97.8%. A Taft linear free energy relationship is noted for the catalysed reaction with ρ* = 0.233 and indicating electron withdrawing groups enhance the rate. An isokinetic relation is observed with β = 358 K indicating that enthalpy factor controls the reaction rate. The result of this paper suggests the possibility of degradation of organic compounds, industrial effluants and toxic organic compounds by photodegradation process by ecofriendly Al<sub>2</sub>S<sub>3</sub>/ MoS<sub>2</sub>. The antibacterial activity of Al<sub>2</sub>S<sub>3</sub>/MoS<sub>2</sub> nanocomposite was investigated. These particles were shown to have an effective bactericide. 展开更多
关键词 Electrochemical method Al2s3/Mos2 Nanoparticles Carboxylic Acids LFER Antibacterial Activity
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Analysis and Simulation of the Influence of Electromagnetic Fields on Living Beings near HV Power Lines Using the FDTD Method
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作者 Anthony Bassesuka Sandoka Nzao 《Open Journal of Applied Sciences》 2023年第12期2343-2359,共17页
Recent decades have seen rapid advances in the field of electrical engineering, such that our environment has become a sea of electrical and magnetic signals, raising questions about the possible effects of low-freque... Recent decades have seen rapid advances in the field of electrical engineering, such that our environment has become a sea of electrical and magnetic signals, raising questions about the possible effects of low-frequency electromagnetic fields on the environment and which are capable of modifying and destroying our ecosystem. Particular interest was given in this article due to a massive influx of population living near high voltage lines. The analysis and simulation of the influence of low frequency electromagnetic fields on living beings in the vicinity of high voltage sources 132 kV and 220 kV in urban areas in DR Congo is the subject of our research with a view to estimating the level of exposure of humans to low frequency electromagnetic fields. To carry out our research, we used the classic method of analyzing the field produced near a high voltage line based on Maxwell’s image theory, the Maxwell-Gauss theorem and Maxwell-Ampère theorem to model and quantify low-frequency electromagnetic fields in the vicinity of high-voltage lines. The 2D FDTD numerical formulation was developed from telegraphers’ equations and allowed us to obtain models of current and voltage induced by electromagnetic fields on living beings below and near HV lines. The different simulations carried out on the proposed models illustrate the effects of the electrical and geometric parameters of the pylons on the distribution of the electromagnetic field in the vicinity of the HV lines. The results obtained were compared to the safety limits recommended by the standards. 展开更多
关键词 Low Frequency Electromagnetic Field Modeling Field and Health Maxwell’s Equations FDTD method Electromagnetic Compatibility High Voltage Line
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基于等效结构应力法的高强钢焊接结构低温主S-N曲线
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作者 高杰 鞠晓臣 +2 位作者 左照坤 赵欣欣 段梦兰 《船舶力学》 EI CSCD 北大核心 2024年第4期571-581,共11页
现有的疲劳S-N曲线已不再适用于北极的低温环境,为了评估北极海洋工程设备材料的低温疲劳寿命,有必要建立金属结构尤其是焊接结构的低温疲劳S-N曲线。本文基于等效结构应力法,计算出Q690高强钢管环焊缝的主S-N曲线,并通过共振疲劳试验... 现有的疲劳S-N曲线已不再适用于北极的低温环境,为了评估北极海洋工程设备材料的低温疲劳寿命,有必要建立金属结构尤其是焊接结构的低温疲劳S-N曲线。本文基于等效结构应力法,计算出Q690高强钢管环焊缝的主S-N曲线,并通过共振疲劳试验对该方法进行了验证。在此基础上,结合大量的高强钢焊接结构试验结果,将温度敏感因子c引入到低温疲劳主S-N曲线的推导中,首次建立了基于低温金属焊接结构的主S-N曲线,并对文献中的疲劳S-N试验数据和ASME中的修正方法进行了对比和验证。结果表明,等效结构应力法能够较准确地计算出焊缝疲劳S-N曲线,推导出的金属焊接结构低温主S-N曲线与试验曲线吻合较好,能够满足低温地区工程要求,可为高强钢焊接结构在北极地区低温环境中的广泛应用提供理论指导。该方法可以为金属焊接结构的低温疲劳研究节省大量的成本,减少非标准试验操作造成的不必要的误差。这对北极海洋工程设备的设计、安全运行和疲劳评估具有重要意义。 展开更多
关键词 等效结构应力法 焊接结构 低温主s-N曲线 温度敏感系数
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