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Corrigendum to“Nitrosamines crisis in pharmaceuticals-Insights on toxicological implications,root causes and risk assessment:A systematic review”[J.Pharm.Anal.14(2024)100919] 被引量:1
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作者 Hemanth P.R.Vikram Tegginamath Pramod Kumar +9 位作者 Gunjan Kumar Narasimha M.Beeraka Rajashree Deka Sheik Mohammed Suhail Sandeep Jat Namitha Bannimath Gayatiri Padmanabhan Ravandur S.Chandan Pramod Kumar Bannimath Gurupadayya 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2024年第6期934-936,共3页
Original statement in the Section 2:2.Literature search Our primary screening of 180 articles yielded the relevant data for this study.2.1.Study selection A total of 180 articles spanning from 1960 to the present day,... Original statement in the Section 2:2.Literature search Our primary screening of 180 articles yielded the relevant data for this study.2.1.Study selection A total of 180 articles spanning from 1960 to the present day,including original research,reviews,case reports and studies reporting nitrosamine impurities above the no-observed-adverse-effect levels(NOAEL)established by regulatory agencies,were initially screened.During the primary screening,we considered factors such as relevance,publication date,access to the full article text,and content. 展开更多
关键词 STATEMENT initially spanning
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On Spanning Wide Diameter of Graphs
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作者 WANG Yameng YIMINGJIANG Shabier 《新疆大学学报(自然科学版中英文)》 CAS 2024年第5期571-578,590,共9页
A t-container Ct(u,v)is a set of t internally disjoint paths between two distinct vertices u and v in a graph G,i.e.,Ct(u,v)={P_(1),P_(2),···,Pt}.Moreover,if V(P_(1))∪V(P_(2))∪···∪V(Pt... A t-container Ct(u,v)is a set of t internally disjoint paths between two distinct vertices u and v in a graph G,i.e.,Ct(u,v)={P_(1),P_(2),···,Pt}.Moreover,if V(P_(1))∪V(P_(2))∪···∪V(Pt)=V(G)then Ct(u,v)is called a spanning t-container,denoted by C_(t)^(sc)(u,v).The length of C_(t)^(sc)(u,v)={P_(1),P_(2),···,Pt}is l(C_(t)^(sc)(u,v))=max{l(P_(i))|1≤i≤t}.A graph G is spanning t-connected if there exists a spanning t-container between any two distinct vertices u and v in G.Assume that u and v are two distinct vertices in a spanning t-connected graph G.Let D_(t)^(sc)(u,v)be the collection of all C_(t)^(sc)(u,v)’s.Define the spanning t-wide distance between u and v in G,d_(t)^(sc)(u,v)=min{l(C_(t)^(sc)(u,v))|C_(t)^(sc)(u,v)∈D_(t)^(sc)(u,v)},and the spanning t-wide diameter of G,D_(t)^(sc)(G)=max{d_(t)^(sc)(u,v)|u,v∈V(G)}.In particular,the spanning wide diameter of G is D_(κ)^(sc)(G),whereκis the connectivity of G.In the paper we provide the upper and lower bounds of the spanning wide diameter of a graph,and show that the bounds are best possible.We also determine the exact values of wide diameters of some well known graphs including Harary graphs and generalized Petersen graphs et al.. 展开更多
关键词 CONNECTIVITY spanning connectivity spanning laceability wide diameter spanning wide diameter
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Brain Functional Network Based on Small-Worldness and Minimum Spanning Tree for Depression Analysis 被引量:1
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作者 Bingtao Zhang Dan Wei +1 位作者 Yun Su Zhonglin Zhang 《Journal of Beijing Institute of Technology》 EI CAS 2023年第2期198-208,共11页
Since the outbreak and spread of corona virus disease 2019(COVID-19),the prevalence of mental disorders,such as depression,has continued to increase.To explore the abnormal changes of brain functional connections in p... Since the outbreak and spread of corona virus disease 2019(COVID-19),the prevalence of mental disorders,such as depression,has continued to increase.To explore the abnormal changes of brain functional connections in patients with depression,this paper proposes a depression analysis method based on brain function network(BFN).To avoid the volume conductor effect,BFN was constructed based on phase lag index(PLI).Then the indicators closely related to depression were selected from weighted BFN based on small-worldness(SW)characteristics and binarization BFN based on the minimum spanning tree(MST).Differences analysis between groups and correlation analysis between these indicators and diagnostic indicators were performed in turn.The resting state electroencephalogram(EEG)data of 24 patients with depression and 29 healthy controls(HC)was used to verify our proposed method.The results showed that compared with HC,the information processing of BFN in patients with depression decreased,and BFN showed a trend of randomization. 展开更多
关键词 DEPRESSION brain function network(BFN) small-worldness(SW) minimum spanning tree(MST)
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The effect of functional loads on free spanning pipeline's VIV response 被引量:3
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作者 艾尚茂 孙丽萍 《Journal of Marine Science and Application》 2009年第2期151-155,共5页
During the operation and installation of offshore pipelines, high axial forces and pressures are experienced, and their effects cannot be neglected. In this article, the effect of internal flow velocity and functional... During the operation and installation of offshore pipelines, high axial forces and pressures are experienced, and their effects cannot be neglected. In this article, the effect of internal flow velocity and functional loads on vortex-induced vibration (VIV) response is investigated. On the basis of the Hamilton principle, a differential equation was derived to describe the motion of a pinned-pinned tensioned spanning pipeline conveying fluid. The VIV response was calculated according to DNV-RP-F105 under different functional loads. The results showed that functional loads influence free spanning pipeline VIV response by changing the natural frequency. Internal flow velocity was found less important for VIV response than other functional load factors, such as effective axial force, because the speed in reality is not high enough to be significant. The research may provide a reference for sensitivity studies of the effect of functional loads on allowable free span lengths. 展开更多
关键词 free spanning pipeline VIV functional load internal flow
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基于对span的预判断和多轮分类的实体关系抽取
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作者 佟缘 姚念民 《计算机工程与科学》 CSCD 北大核心 2024年第5期916-928,共13页
针对自然语言处理领域中的实体识别和关系抽取任务,提出一种对词元序列(Token Sequence,又称span)进行预测的模型Smrc。模型整体上利用BERT预训练模型作为编码器,另外包含实体预判断(Pej)、实体多轮分类(Emr)和关系多轮分类(Rmr)3个模块... 针对自然语言处理领域中的实体识别和关系抽取任务,提出一种对词元序列(Token Sequence,又称span)进行预测的模型Smrc。模型整体上利用BERT预训练模型作为编码器,另外包含实体预判断(Pej)、实体多轮分类(Emr)和关系多轮分类(Rmr)3个模块。Smrc模型通过Pej模块的初步判断及Emr模块的多轮实体分类来进行实体识别,再利用Rmr模块的多轮关系分类来判断实体对间的关系,进而完成关系抽取任务。在CoNLL04、SciERC和ADE 3个实验数据集上,Smrc模型的实体识别F1值分别达到89.67%,70.62%和89.56%,关系抽取F1值分别达到73.11%,51.03%和79.89%,相较之前在3个数据集上的最佳模型Spert,Smrc模型凭借实体预判断和实体及关系多轮分类,在2个子任务上其F1值分别提高了0.73%,0.29%,0.61%及1.64%,0.19%,1.05%,表明了该模型的有效性及其优势。 展开更多
关键词 对span的预判断 实体关系抽取 BERT预训练模型 多轮实体分类 多轮关系分类
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Application of excavation compensation method for enhancing stability and efficiency in shallow large-span rock tunnels
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作者 BIAN Wen-hui YANG Jun +2 位作者 ZHU Chun WANG Ke-xue XU Dong-ming 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第9期3242-3263,共22页
Engineering shallow,large-span rock tunnels challenges deformation control and escalates construction costs.This study investigates the excavation compensation method(ECM)and its associated technologies to address the... Engineering shallow,large-span rock tunnels challenges deformation control and escalates construction costs.This study investigates the excavation compensation method(ECM)and its associated technologies to address these issues.Utilizing five key technologies,the ECM effectively modulates radial stress post-excavation,redistributes stress in the surrounding rock,and eliminates tensile stress at the excavation face.Pre-tensioning measures further enhance the rock’s residual strength,establishing a new stability equilibrium.Field tests corroborate the method’s effectiveness,demonstrating a crown settlement reduction of 3–8 mm,a nearly 50%decrease compared to conventional construction approaches.Additionally,material consumption and construction duration were reduced by approximately 30%–35%and 1.75 months per 100 m,respectively.Thus,the ECM represents a significant innovation in enhancing the stability and construction efficiency of large-span rock tunnels,marking a novel contribution to the engineering field. 展开更多
关键词 excavation compensation method rocky tunnels shallow spanning tunnels tunnel support field test
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基于最小Spanning树的中继节点部署算法
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作者 沈俊鑫 南金秀 张经阳 《传感器与微系统》 CSCD 2018年第10期153-156,共4页
在能量受限的无线传感器网络(WSNs)中,部署中继节点成为确保通信覆盖的常用方法。提出基于最小Spanning树的中继节点部署算法(MST-DRN)。MST-DRN算法引用基于无线充电的能量模型。再依据节点的能量采集率计算边权值。依据边权值的图模... 在能量受限的无线传感器网络(WSNs)中,部署中继节点成为确保通信覆盖的常用方法。提出基于最小Spanning树的中继节点部署算法(MST-DRN)。MST-DRN算法引用基于无线充电的能量模型。再依据节点的能量采集率计算边权值。依据边权值的图模型构建最小Spanning树(MST)。检测MST中不满足生存条件的非支叶节点,在节点附近部署中继节点,维持网络连通。实验数据表明:提出的MST-DRN算法在确保网络连通时,减少了成本(中继节点数),并提高了数据包传递率。 展开更多
关键词 无线传感器网络 中继节点 最小spanning 能量采集率 无线充电
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Hepatic Morphometric Correlation with Biophysical Profiling of Height
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作者 Precious Belema Ibiabuo 《Journal of Biosciences and Medicines》 2024年第7期194-206,共13页
Introduction: Clinical assessment of hepatic span is usually subjective. And is based on the experience of the clinician. This is what has led to this study in using Biophysical profiling of Heights, Weights, and Body... Introduction: Clinical assessment of hepatic span is usually subjective. And is based on the experience of the clinician. This is what has led to this study in using Biophysical profiling of Heights, Weights, and Body mass index to find the normal hepatic span of every individual. This study was conducted at HMG Hospital Limited, Abonnema in Rivers State in affiliation with the University of Port Harcourt. Methodology: The biophysical sampling method was instituted to select respondents. At the same time, a radiological formula was used to calculate the sample size, and subjects’ weight, height and hepatic span where measured while the BMI was calculated and the data was analyzed using python programming language for data science. Results: The data obtained were subjected to descriptive statistics and the Pearson correlation coefficient. P value greater than or equal to 0.05 was taken as statistically significant. The respondents were mainly aged 30 to 63 years. Conclusion: The null hypothesis was rejected;hence this research has stated the law known as Belema’s Law of hepatic-height correlation, which states that the hepatic span of an individual is directly proportional to the height of that individual except in disease conditions affecting the liver directly or indirectly. 展开更多
关键词 Hepatic Span HEIGHT Body Mass Index Weight
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A NEW ALGORITHM FOR ALL EFFICIENT SPANNING TREES
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作者 倪勤 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1997年第1期32-36,共5页
In Corley′s algorithm for all efficient spanning trees, final solutions include many spanning trees, which are not all efficient. In this paper, a new algorithm is presented, which corrects and modifies Corley′s alg... In Corley′s algorithm for all efficient spanning trees, final solutions include many spanning trees, which are not all efficient. In this paper, a new algorithm is presented, which corrects and modifies Corley′s algorithm. A necessary condition is developed for the subtree of an efficient spanning tree. According to the condition the new algorithm is established and its efficiency is proved. 展开更多
关键词 combinatorial programming ALGORITHMS Pareto optimal efficient spanning tree
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A Review of the Key Points in the Design of Small-Radius Curved Ramp Bridges
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作者 Yuxiao Zhang 《Journal of World Architecture》 2024年第1期97-102,共6页
This article explores the fundamentals of small-radius curved ramp bridges.It covers the selection of box girder spans,support methods,and forms,along with design optimization techniques for this type of bridge struct... This article explores the fundamentals of small-radius curved ramp bridges.It covers the selection of box girder spans,support methods,and forms,along with design optimization techniques for this type of bridge structure.The purpose of this paper is to provide robust support for enhancing the design quality of these bridges and ensuring their efficacy in real-world applications. 展开更多
关键词 Bridge design Small-radius curve ramp Box girder span Support method Support form
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Modeling and optimization of unbalanced multi-stage logistic system
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作者 徐杭 徐榕 叶庆泰 《Journal of Southeast University(English Edition)》 EI CAS 2005年第2期220-224,共5页
To decompose an unbalanced multi-stage logistic system to multipleindependent single-stage logistic systems, a new notion of parameterized interface distribution ispresented. For encoding the logistic pattern on each ... To decompose an unbalanced multi-stage logistic system to multipleindependent single-stage logistic systems, a new notion of parameterized interface distribution ispresented. For encoding the logistic pattern on each stage, the Pruefer number is used. With theimproved decoding procedure, any Pruefer number produced stochastically can be decoded to a feasiblelogistic pattern, which can match with the capacities of the nodes of the logistic system. Withthese two innovations, a new modeling method based on parameterized interface distribution and thePriifer number coding is put forward. The corresponding genetic algorithm, named as PIP-GA, can findbetter solutions and require less computational time than st-GA. Although requiring a little moreconsumption of memory, PIP-GA is still an efficient and robust method in the modeling andoptimization of unbalanced multi-stage logistic systems. 展开更多
关键词 LOGISTICS optimization genetic algorithm Priifer number spanning tree parameterized interface distribution unbalanced multi-stage logistic system
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Experimental Study on Free Spanning Submarine Pipeline Under Dynamic Excitation 被引量:9
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作者 李昕 刘亚坤 +2 位作者 周晶 马恒春 朱彤 《China Ocean Engineering》 SCIE EI 2002年第4期537-548,共12页
Seismic load has a significant effect on the response of a free spanning submarine pipeline when the pipeline is constructed in a seismically active region. The model experiment is performed on an underwater shaking t... Seismic load has a significant effect on the response of a free spanning submarine pipeline when the pipeline is constructed in a seismically active region. The model experiment is performed on an underwater shaking table to simulate the response of submarine pipelines under dynamic input. In consideration of the effects of the terrestrial and submarine pipeline, water depth, support condition, distance from seabed, empty and full pipeline, and span on dynamic response, 120 groups of experiments are conducted. Affecting factors are analyzed and conclusions are drawn for reference. For the control of dynamic response, the span of a submarine pipeline is by far more important than the other factors. Meanwhile, the rosponse difference between a submarine pipeline under sine excitation and that under random excitation exists in experiments. 展开更多
关键词 free spanning submarine pipeline underwater shaking table model experiment dynamic response factor analysis
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Effect of Internal Flow on Vortex-Induced Vibration of Submarine Free Spanning Pipelines 被引量:10
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作者 娄敏 丁坚 +1 位作者 郭海燕 董晓林 《China Ocean Engineering》 SCIE EI 2005年第1期147-154,共8页
At present, most researches on the vortex-induced vibration of submarine free spanning pipelines ignore the effect of internal flowing fluid; furthermore, there are no research reports considering the coupling effect ... At present, most researches on the vortex-induced vibration of submarine free spanning pipelines ignore the effect of internal flowing fluid; furthermore, there are no research reports considering the coupling effect of internal and external fluid with the free span. In this paper, combining Iwan's wake oscillator model with the differential equation derived for the dynamic response of submarine free spanning pipelines with inclusion of internal flow, the pipe-fluid coupling equations are developed to investigate the effect of internal flow on the vortex-induced vibration of the free spans. The finite element approximation is implemented to derive the matrix equations of equilibrium. The Newmark method combined with simple iteration is used to solve the system of equations. The results indicate that the internal fluid flow may cause the shift of resonance band to the lower frequency and a slight decrease in the peak value; the effect will be more pronounced with the increase of the span length and can be weakened in the presence of the axial tension. 展开更多
关键词 vortex-induced vibration internal flow free span submarine pipelines
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Analysis of Dynamic Characteristics of Submarine Free Spanning Pipelines by Complex Damping Method 被引量:5
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作者 傅强 郭海燕 杨新华 《海洋工程:英文版》 2004年第3期485-491,共7页
Considering the effect of the internal flowing fluid and the external marine environmental condition, the differential equation for the vortex induced vibration (VIV) of the free spanning pipeline is derived and is d... Considering the effect of the internal flowing fluid and the external marine environmental condition, the differential equation for the vortex induced vibration (VIV) of the free spanning pipeline is derived and is discretized by the Hermit interpolation function. The free vibration equation with the damping term is solved by the complex damping method for the natural frequency, and then the effect of fluid damping on the natural frequency of the free spanning pipeline is analyzed. The results show that fluid damping has a significant influence on the damped natural frequency of the free spanning pipeline in the lock in state, while it has little influence when the pipeline is out of the lock in state. In the meantime, the change of the free span length has the same effect on the damped natural frequency and the undamped natural frequency. 展开更多
关键词 free spanning pipelines natural frequency complex damping fluid damping
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Study on Model Tests and Hydrodynamic Force Models for Free Spanning Submarine Pipelines Subjected to Earthquakes 被引量:3
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作者 李明高 李昕 +2 位作者 董汝博 周晶 关炯 《China Ocean Engineering》 SCIE EI 2010年第2期305-320,共16页
A test rig is built to model the dynamic response of submarine pipelines with an underwater shaking table in the State Key Laboratory of Coastal and Offshore Engineering, Dalian University of Technology, China. Model ... A test rig is built to model the dynamic response of submarine pipelines with an underwater shaking table in the State Key Laboratory of Coastal and Offshore Engineering, Dalian University of Technology, China. Model tests are carried out to consider the effects of exciting wave directions and types. Based on the experimental results, two hydrodynamic force models derived from Morisen equation and Wake model are presented respectively. By use of hydrodynamic force models suitable for free spanning submarine pipelines under earthquakes, diseretized equations of motion are obtained and finite element models are established to analyze dynamic response of free spanning submarine pipeline subjected to multi-support seismic excitations. The comparison of numerical results with experimental results shows that the improved Morison and Wake hydrodynamic force models could satisfactorily predict dynamic response on the free spanning submarine pipelines subjected to earthquakes. 展开更多
关键词 free spanning submarine pipelines model tests hydrodynamic force models dynamic response analysis earthquke
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Composite active control system of roof and side truss cable for large section coal roadway in fold coal pillar area 被引量:5
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作者 Sheng-Rong XIE Er-Peng LI Fu-Lian HE Shou-Bao ZHANG Guang-Chao ZHANG Mao-Yu PANG 《Journal of Coal Science & Engineering(China)》 2013年第2期126-132,共7页
In order to solve the surrounding rock control problem of large section gangue replacement roadway under complicated conditions, this paper analyzed the impact to the roadway controlling produced by the geological con... In order to solve the surrounding rock control problem of large section gangue replacement roadway under complicated conditions, this paper analyzed the impact to the roadway controlling produced by the geological conditions such as high ground stress, folded structure tilted roof asymmetry and soft wall rock, and built the tilt layered roof structural mechanics model to clarify the increase span mechanism of the weak coal instability. Then, we proposed the combined control system including roof inclined truss cable, coal-side cable-channel steel and intensive bolt support. And then by building the structural mechanics model of roof inclined truss cable system, the support principle was described. Besides, according to this model, we deduced the calculation formula of cable anchoring force and its tensile stress. Finally surrounding rock control technology of large section roadway in fold coal pillar area was formed. Field practice shows that the greatest roof convergence of gangue replacement roadway is 158 mm and coal-side deformation is 243 mm. Roadway deformation is controlled effectively and technical support is provided for replacement mining. 展开更多
关键词 fold coal pillar area increase span mechanism roof inclined truss cable system coal-side cable-channel steel structural mechanics model
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SOLVING MINIMUM SPANNING TREE PROBLEM WITH DNA COMPUTING 被引量:3
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作者 LiuXikui LiYan XuJin 《Journal of Electronics(China)》 2005年第2期112-117,共6页
Molecular programming is applied to minimum spanning problem whose solution requires encoding of real values in DNA strands. A new encoding scheme is proposed for real values that is biologically plausible and has a f... Molecular programming is applied to minimum spanning problem whose solution requires encoding of real values in DNA strands. A new encoding scheme is proposed for real values that is biologically plausible and has a fixed code length. According to the characteristics of the problem, a DNA algorithm solving the minimum spanning tree problem is given. The effectiveness of the proposed method is verified by simulation. The advantages and disadvantages of this algorithm are discussed. 展开更多
关键词 DNA computing Genetic algorithms Minimum spanning tree problem
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An Explicit Integer Programming Model of the Minimal Spanning Tree Problem for Digraphs with Asymmetric Weights 被引量:1
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作者 Feng Junwen(Naming University of Science and Technology, 210094, P. R. China) 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1998年第2期70-81,共12页
As far as the minimal spanning tree problem for the digraph with asymmetric weightsis concerned, an explicit integer programming model is proposed, which could be solved successfullyusing the integer programming packa... As far as the minimal spanning tree problem for the digraph with asymmetric weightsis concerned, an explicit integer programming model is proposed, which could be solved successfullyusing the integer programming packages such as LINDO, and furthermore this model is extendedinto the stochastic version, that is, the minimal spanning tree problem for the digraph with theweights is not constant but random variables. Several algorithms are also developed to solve themodels. Finally, a numerical demonstration is given. 展开更多
关键词 Minimal spanning tree DIGRAPH Integer programming Asymmetric weight Stochastic spanning tree
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Maximizing Convergence Speed for Second Order Consensus in Leaderless Multi-Agent Systems 被引量:1
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作者 Gianvito Difilippo Maria Pia Fanti Agostino Marcello Mangini 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2022年第2期259-269,共11页
The paper deals with the consensus problem in a leaderless network of agents that have to reach a common velocity while forming a uniformly spaced string.Moreover,the final common velocity(reference velocity)is determ... The paper deals with the consensus problem in a leaderless network of agents that have to reach a common velocity while forming a uniformly spaced string.Moreover,the final common velocity(reference velocity)is determined by the agents in a distributed and leaderless way.Then,the consensus protocol parameters are optimized for networks characterized by a communication topology described by a class of directed graphs having a directed spanning tree,in order to maximize the convergence rate and avoid oscillations.The advantages of the optimized consensus protocol are enlightened by some simulation results and comparison with a protocol proposed in the related literature.The presented protocol can be applied to coordinate agents such as mobile robots,automated guided vehicles(AGVs)and autonomous vehicles that have to move with the same velocity and a common inter-space gap. 展开更多
关键词 Consensus protocols directed spanning tree multiagent systems networked systems second-order consensus
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Spanning tree-based algorithm for hydraulic simulation of large-scale water supply networks 被引量:1
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作者 Huan-feng DUAN Guo-ping YU 《Water Science and Engineering》 EI CAS 2010年第1期23-35,共13页
With the purpose of making calculation more efficient in practical hydraulic simulations, an improved algorithm was proposed and was applied in the practical water distribution field. This methodology was developed by... With the purpose of making calculation more efficient in practical hydraulic simulations, an improved algorithm was proposed and was applied in the practical water distribution field. This methodology was developed by expanding the traditional loop-equation theory through utilization of the advantages of the graph theory in efficiency. The utilization of the spanning tree technique from graph theory makes the proposed algorithm efficient in calculation and simple to use for computer coding. The algorithms for topological generation and practical implementations are presented in detail in this paper. Through the application to a practical urban system, the consumption of the CPU time and computation memory were decreased while the accuracy was greatly enhanced compared with the present existing methods. 展开更多
关键词 large-scale networks hydraulic simulation graph theory fundamental loop spanning tree EFFICIENCY
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