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Complexity analysis of blast-induced vibrations in underground mining: A case study 被引量:3
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作者 Cardu Marilena Dompieri Mauricio Seccatore Jacopo 《International Journal of Mining Science and Technology》 SCIE EI 2012年第1期125-131,共7页
Blasting in geological bodies is an industrial process acting in an environment characterized by high uncertainties (natural joints, faults, voids, abrupt structural changes), which are transposed into the process par... Blasting in geological bodies is an industrial process acting in an environment characterized by high uncertainties (natural joints, faults, voids, abrupt structural changes), which are transposed into the process parameters (e.g. energetic transfer to rock mass, hole deviations, misfires, vibrations, fly-rock, etc.). The approach to this problem searching for the "optimum" result can be ineffective. The geological environment is marked out by too many uncertainties, to have an "optimum" suitable to different applications. Researching for "Robustness" in a blast design gives rise to much more efficiency. Robustness is the capability of the system to behave constantly under varying conditions, without leading to unexpected results. Since the geology varies from site to site, setting a robust method can grant better results in varying environments, lowering the costs and increasing benefits and safety. Complexity Analysis (C.A.) is an innovative approach to systems. C.A. allows analyzing the Complexity of the Blast System and the criticality of each variable (drilling, charging and initiation parameters). The lower is the complexity, the more robust is the system, and the lower is the possibility of unexpected results. The paper presents the results obtained thanks to the C.A. approach in an underground gypsum quarry (Italy), exploited by conventional rooms and pillars method by drilling and blasting. The application of C.A. led to a reliable solution to reduce the charge per delay, hence reducing the impact of ground vibration on the surrounding structures. The analysis of the correlation degree between the variables allowed recognizing empirical laws as well. 展开更多
关键词 Drilling and blasting complexity analysis Vibrations control
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Complexity Analysis and Algorithm Design of Pooling Problem 被引量:1
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作者 Yu-Hong Dai Rui Diao Kai Fu 《Journal of the Operations Research Society of China》 EI CSCD 2018年第2期249-266,共18页
The pooling problem,also called the blending problem,is fundamental in production planning of petroleum.It can be formulated as an optimization problem similar with the minimum-cost flow problem.However,Alfaki and Hau... The pooling problem,also called the blending problem,is fundamental in production planning of petroleum.It can be formulated as an optimization problem similar with the minimum-cost flow problem.However,Alfaki and Haugland(J Glob Optim 56:897–916,2013)proved the strong NP-hardness of the pooling problem in general case.They also pointed out that it was an open problem to determine the computational complexity of the pooling problem with a fixed number of qualities.In this paper,we prove that the pooling problem is still strongly NP-hard even with only one quality.This means the quality is an essential difference between minimum-cost flow problem and the pooling problem.For solving large-scale pooling problems in real applications,we adopt the non-monotone strategy to improve the traditional successive linear programming method.Global convergence of the algorithm is established.The numerical experiments show that the non-monotone strategy is effective to push the algorithm to explore the global minimizer or provide a good local minimizer.Our results for real problems from factories show that the proposed algorithm is competitive to the one embedded in the famous commercial software Aspen PIMS. 展开更多
关键词 Pooling problem complexity analysis Successive linear programming Non-monotone
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Optimizing Connections:Applied Shortest Path Algorithms for MANETs
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作者 Ibrahim Alameri Jitka Komarkova +2 位作者 Tawfik Al-Hadhrami Abdulsamad Ebrahim Yahya Atef Gharbi 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第10期787-807,共21页
This study is trying to address the critical need for efficient routing in Mobile Ad Hoc Networks(MANETs)from dynamic topologies that pose great challenges because of the mobility of nodes.Themain objective was to del... This study is trying to address the critical need for efficient routing in Mobile Ad Hoc Networks(MANETs)from dynamic topologies that pose great challenges because of the mobility of nodes.Themain objective was to delve into and refine the application of the Dijkstra’s algorithm in this context,a method conventionally esteemed for its efficiency in static networks.Thus,this paper has carried out a comparative theoretical analysis with the Bellman-Ford algorithm,considering adaptation to the dynamic network conditions that are typical for MANETs.This paper has shown through detailed algorithmic analysis that Dijkstra’s algorithm,when adapted for dynamic updates,yields a very workable solution to the problem of real-time routing in MANETs.The results indicate that with these changes,Dijkstra’s algorithm performs much better computationally and 30%better in routing optimization than Bellman-Ford when working with configurations of sparse networks.The theoretical framework adapted,with the adaptation of the Dijkstra’s algorithm for dynamically changing network topologies,is novel in this work and quite different from any traditional application.The adaptation should offer more efficient routing and less computational overhead,most apt in the limited resource environment of MANETs.Thus,from these findings,one may derive a conclusion that the proposed version of Dijkstra’s algorithm is the best and most feasible choice of the routing protocol for MANETs given all pertinent key performance and resource consumption indicators and further that the proposed method offers a marked improvement over traditional methods.This paper,therefore,operationalizes the theoretical model into practical scenarios and also further research with empirical simulations to understand more about its operational effectiveness. 展开更多
关键词 Dijkstra’s algorithm optimization complexity analysis shortest path first comparative algorithm analysis nondeterministic polynomial(NP)-complete
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Discovering hidden information of gene ontology based on complex networks analysis 被引量:3
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作者 唐晋韬 王挺 王戟 《Journal of Southeast University(English Edition)》 EI CAS 2010年第1期31-35,共5页
To resolve the ontology understanding problem, the structural features and the potential important terms of a large-scale ontology are investigated from the perspective of complex networks analysis. Through the empiri... To resolve the ontology understanding problem, the structural features and the potential important terms of a large-scale ontology are investigated from the perspective of complex networks analysis. Through the empirical studies of the gene ontology with various perspectives, this paper shows that the whole gene ontology displays the same topological features as complex networks including "small world" and "scale-free",while some sub-ontologies have the "scale-free" property but no "small world" effect.The potential important terms in an ontology are discovered by some famous complex network centralization methods.An evaluation method based on information retrieval in MEDLINE is designed to measure the effectiveness of the discovered important terms.According to the relevant literature of the gene ontology terms,the suitability of these centralization methods for ontology important concepts discovering is quantitatively evaluated.The experimental results indicate that the betweenness centrality is the most appropriate method among all the evaluated centralization measures. 展开更多
关键词 gene ontology complex network analysis centrality measure
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Arrhythmia Detection by Using Chaos Theory with Machine Learning Algorithms
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作者 Maie Aboghazalah Passent El-kafrawy +3 位作者 Abdelmoty M.Ahmed Rasha Elnemr Belgacem Bouallegue Ayman El-sayed 《Computers, Materials & Continua》 SCIE EI 2024年第6期3855-3875,共21页
Heart monitoring improves life quality.Electrocardiograms(ECGs or EKGs)detect heart irregularities.Machine learning algorithms can create a few ECG diagnosis processing methods.The first method uses raw ECG and time-s... Heart monitoring improves life quality.Electrocardiograms(ECGs or EKGs)detect heart irregularities.Machine learning algorithms can create a few ECG diagnosis processing methods.The first method uses raw ECG and time-series data.The second method classifies the ECG by patient experience.The third technique translates ECG impulses into Q waves,R waves and S waves(QRS)features using richer information.Because ECG signals vary naturally between humans and activities,we will combine the three feature selection methods to improve classification accuracy and diagnosis.Classifications using all three approaches have not been examined till now.Several researchers found that Machine Learning(ML)techniques can improve ECG classification.This study will compare popular machine learning techniques to evaluate ECG features.Four algorithms—Support Vector Machine(SVM),Decision Tree,Naive Bayes,and Neural Network—compare categorization results.SVM plus prior knowledge has the highest accuracy(99%)of the four ML methods.QRS characteristics failed to identify signals without chaos theory.With 99.8%classification accuracy,the Decision Tree technique outperformed all previous experiments. 展开更多
关键词 ECG extraction ECG leads time series prior knowledge and arrhythmia chaos theory QRS complex analysis machine learning ECG classification
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Species distribution of polymeric aluminium ferrum——timed complexation colorimetric analysis method of Al-Fe-Ferron 被引量:8
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作者 Hu, YY Tu, CQ Wu, HH 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2001年第4期418-421,共4页
The effects of the calorimetric buffer solutions were investigated while the two colorimetric reactions of AI-ferron complex and Fe-ferron complex occurred individually, and the effects of the testing wavelength and t... The effects of the calorimetric buffer solutions were investigated while the two colorimetric reactions of AI-ferron complex and Fe-ferron complex occurred individually, and the effects of the testing wavelength and the pH of the solutions were also investigated. A timed complexatian colorimetric analysis method of Al-Fe-ferron in view of the total concentration of {AI + Fe} was then established to determine the species distribution of polymeric Al-Fe. The testing wavelength was recommended at 362 net and the testing pH value was 5. With a comparison of the ratios of n(Al)/n(Fe), the standard adsorption curves of the polymeric Al-Fe solutions were derived from the experimental results. Furthermore, the solutions' composition were carious in both the molar n(Al)/n(Fe) ratios, i.e. 0/0, 5/5, 9/1 and 0/10, and the concentrations associated with the total ( Al + Fe which ranged from 10(-5) to 10(-4) mol/L.. 展开更多
关键词 polymeric aluminum-ferrum species distribution timed complexation colarimetric analysis method Al-Fe-ferron
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Core acupoints of acupuncture for hyperplasia of mammary gland: a network analysis 被引量:1
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作者 Bao-Min Dou Yuan-Yuan Sun +4 位作者 Tian-Yi Zhao Qian-Nan Jia Jiang Liu Bo Chen Yi Guo 《TMR Non-Drug Therapy》 2020年第1期12-22,共11页
Backgroud:Clinical studies on acupuncture treatment of hyperplasia of mammary gland(HMG)have proved its effectiveness,but most studies have paid little attention to acupoints prescription and acupoint compatibility.Th... Backgroud:Clinical studies on acupuncture treatment of hyperplasia of mammary gland(HMG)have proved its effectiveness,but most studies have paid little attention to acupoints prescription and acupoint compatibility.The clinical prescription is not identical,the curative effect also has the difference.Therefore,through data mining and network analysis,this study explored the core acupoints and the compatibility law of acupoints in acupuncture treatment of HMG.Methods:To search and select qualified literature according to inclusion and exclusion criteria for relevant clinical research literature on acupuncture treatment of HMG in CNKI,VIP database,WanFang database and PubMed,etc.Then extract relevant information and establish a database.Using the method of statistical and complex network analysis,this paper studies the core acupoints and the law of acupoint compatibility.Results:A total of 104 Chinese literatures and 0 English literatures were included and 106 acupuncture prescriptions were extracted.The core acupoints in the treatment of HMG are Danzhong(CV 17),Wuyi(ST 15),Zusanli(ST 36),Jianjing(GB 21).Danzhong(CV 17)and Zusanli(ST 36),Danzhong(CV 17)and Wuyi(ST 15),Jianjing(GB 21)and Tianzong(SI 11),Jianjing(GB 21)and Wuyi(ST 15)have the highest correlation degree.The method of acupoint matching mainly consists of local-remote acupoints,upper-lower acupoints and front-rear acupoints.Conclusion:The results of a network analysis substantially accord with the general rules of acupuncture theories in traditional Chinese medicine,able to reflect the points-selection principles and features in acupuncture treatment of HMG and provide evidence for the acupoints selection in the treatment of HMG in acupuncture clinic. 展开更多
关键词 Hyperplasia of mammary glands(HMG) Acupoints compatibility Complex network analysis Traditional Chinese medicine
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A ca. 2.2Ga Acidic Magmatic Event at the Northern Margin of the Yangtze Craton: Evidence from U-Pb Dating and Hf Isotope Analysis of Zircons from the Kongling Complex 被引量:2
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作者 XU Daliang WEI Yunxu +3 位作者 PENG Lianhong DENG Xin HU Kun LIU Hao 《Acta Geologica Sinica(English Edition)》 CAS CSCD 2018年第2期872-873,共2页
Objective The Yangtze craton collisional orogeny at ca. extensional events at ca. 1 experienced Paleoproterozoic 1.95-2.0 Ga and post-orogenic 85 Ga related to amalgamation of the Columbia (Nuna) supercontinent (Zh... Objective The Yangtze craton collisional orogeny at ca. extensional events at ca. 1 experienced Paleoproterozoic 1.95-2.0 Ga and post-orogenic 85 Ga related to amalgamation of the Columbia (Nuna) supercontinent (Zhao and Cawood, 2012). A ca. 2.15 Ga suprasubduction zone ophiolitic melange was recongized in the Archean- Paleoproterozoic Kongling Complex of the northern Yangtze craton (Han et al., 2017). However, the tectonic evolution in early Paleoproterozoic from 2.4 Ga to 2.2 Ga remains unclear. We report here the presence of a suite of Paleoproterozoic (2.2 Ga) granites in the Huangling dome, northern Yangtze craton, which may provide important insights into crustal growth processes in the craton prior to the assembly of Columbia. 展开更多
关键词 Pb HF Acidic Magmatic Event at the Northern Margin of the Yangtze Craton Evidence from U-Pb Dating and Hf Isotope analysis of Zircons from the Kongling Complex Ga
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Complex Seismic Focus Structure and Earthquake-Triggered Landslide Distribution:Analysis of the 2014 Ludian M_w6.1 Earthquake in Yunnan 被引量:3
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作者 CHEN Xiaoli LIU Chunguo 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第2期733-734,共2页
Objective The 2014 Ludian Mw6.1 earthquake in Yunnan occurred in a mountainous area with complex tectonics and topography, which caused serious damage as well as co-seismic landslides of an unusual large scale. Becau... Objective The 2014 Ludian Mw6.1 earthquake in Yunnan occurred in a mountainous area with complex tectonics and topography, which caused serious damage as well as co-seismic landslides of an unusual large scale. Because the suspected seismogenic faults on the surface, distribution of aftershocks and focal mechanism solutions are not consistent, it remains difficult to determine what is the real causal fault or seismogenic structure for this event. Actually, it may imply the complicity of the seismic source at depth. In addition, the distribution of the co- seismic landslides also exhibits some diffusion that is different from general eases, likely associated with the seismic focus structure. 展开更多
关键词 Complex Seismic Focus Structure and Earthquake-Triggered Landslide Distribution:analysis of the 2014 Ludian M_w6.1 Earthquake in Yunnan
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The Space and Time Features of Global SST Anomalies Studied by Complex Principal Component Analysis
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作者 骆美霞 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1999年第1期3-23,5+9+11+15+17+19+21,共19页
In this paper, the variability characteristics of the global field of sea surface temperature (SST) anomaly are studied by complex principal component (c.p.c.) analysis, whose results are also compared with those of r... In this paper, the variability characteristics of the global field of sea surface temperature (SST) anomaly are studied by complex principal component (c.p.c.) analysis, whose results are also compared with those of real p.c. analysis. The data consist of 40 years of global SST monthly averages over latitudes from 42 5°S to 67 5°N. In the spatial domain, it is found that the distribution of the first complex loading amplitude is characterized by three areas of large values: the first one in the eastern and central equatorial Pacific Ocean, the second one in the northern tropical Indian Ocean and South China Sea, the third one in the northern Pacific Ocean. As it will be explained, this pattern may be considered as representative of El Nio mode. The first complex loading phase pattern shows a stationary wave in the Pacific (also revealed by real p.c. analysis) superimposed to an oscillating disturbance, propagating from the Pacific to Indian or the opposite way. A subsequent correlation analysis among different spatial points allows revealing disturbances actually propagating westward from the Pacific to the Indian Ocean, which could therefore represent reflected Rossby waves, i.e. the west phase of the signals that propagate disturbances of thermal structure in the tropical Pacific Ocean. In the time domain, a relation between the trend of the first complex principal component and the ENSO cycle is also established. 展开更多
关键词 Global sea surface temperature anomalies ENSO Complex principal component analysis Travelling disturbances
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Paleoclimate Study of Mountain Ecosystems by Multiple Group Biological Analysis
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作者 Marina SKRYPNIKOVA Olga USPENSKAYA Olga KHOKHLOVA 《Journal of Mountain Science》 SCIE CSCD 2011年第1期24-36,共13页
Methodological problems of climatic reconstruction for different periods of Holocene are discussed on the basis of a multiple group biological analysis on peat-sapropel sediments. The possibility of biological analysi... Methodological problems of climatic reconstruction for different periods of Holocene are discussed on the basis of a multiple group biological analysis on peat-sapropel sediments. The possibility of biological analysis is exemplified by the paleoclimatic reconstruction for Carpathian and Altai Mountain ranges. For the "Skolevsky Beskidy" national park of Carpaty the paleoclimatic scenarios have been drown up aiming at the more precise definition of climatic conditions for the period of mass mountain slope terracing. The stability of terrace systems of various designs in the current climatic conditions has been assessed. It is shown that during periods of humid climate the terraces, whose designs have been focused on drainage, were built. In periods of dry and warm climate the terrace systems capable of accumulating water were built. Both these types of terrace systems are destroyed in nowadays. Only those terrace systems are stable which were adjusted by their builders to contrast variations of precipitation. For Western Altais the paleoclimatic scenario has been done to forecast the safety of the Bronze Age kurgans (burial earth mounds) with permafrost inside the construction. In the Altay region during the Holocene it has revealed two periods of sharp cooling, the peaks of which occurred in the intervals 4500- 4300 and 2500-2300 years pronounced climatic drying ago, and two periods of 4900-4700 and 130-70 years ago. Depletion of the algae composition in the layer corresponding to the last period of drying climate indicates a very sharp change in the parameters of moisture and turning the lake into a dry swamp. Periods of cold weather may have contributed to the formation of special ritual traditions of the Sakan tribes that require the frozen ground to bury the dead. The later climate fluctuations identified have not affected the safety of permafrost in burial mounds constructed in the V-III cc BC. 展开更多
关键词 Climatic reconstruction Complex group biological analysis of peat-sapropel sediments PALEOPEDOLOGY Soil evolution HOLOCENE
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Theoretical convergence analysis of complex Gaussian kernel LMS algorithm
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作者 Wei Gao Jianguo Huang +1 位作者 Jing Han Qunfei Zhang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2016年第1期39-50,共12页
With the vigorous expansion of nonlinear adaptive filtering with real-valued kernel functions,its counterpart complex kernel adaptive filtering algorithms were also sequentially proposed to solve the complex-valued no... With the vigorous expansion of nonlinear adaptive filtering with real-valued kernel functions,its counterpart complex kernel adaptive filtering algorithms were also sequentially proposed to solve the complex-valued nonlinear problems arising in almost all real-world applications.This paper firstly presents two schemes of the complex Gaussian kernel-based adaptive filtering algorithms to illustrate their respective characteristics.Then the theoretical convergence behavior of the complex Gaussian kernel least mean square(LMS) algorithm is studied by using the fixed dictionary strategy.The simulation results demonstrate that the theoretical curves predicted by the derived analytical models consistently coincide with the Monte Carlo simulation results in both transient and steady-state stages for two introduced complex Gaussian kernel LMS algonthms using non-circular complex data.The analytical models are able to be regard as a theoretical tool evaluating ability and allow to compare with mean square error(MSE) performance among of complex kernel LMS(KLMS) methods according to the specified kernel bandwidth and the length of dictionary. 展开更多
关键词 nonlinear adaptive filtering complex Gaussian kernel convergence analysis non-circular data kernel least mean square(KLMS).
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Mathematical theory of signal analysis vs. complex analysis method of harmonic analysis
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作者 QIAN Tao ZHANG Li-ming 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2013年第4期505-530,共26页
We present recent work of harmonic and signal analysis based on the complex Hardy space approach.
关键词 Mobius transform Blaschke form mono-component Hardy space adaptive Fourier decomposi-tion rational approximation rational orthogonal system time-frequency distribution digital signal processing uncertainty principle higher dimensional signal analysis in several complex variables and the Clifford algebrasetting.
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Two new predictor-corrector algorithms for second-order cone programming 被引量:1
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作者 曾友芳 白延琴 +1 位作者 简金宝 唐春明 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2011年第4期521-532,共12页
Based on the ideas of infeasible interior-point methods and predictor-corrector algorithms, two interior-point predictor-corrector algorithms for the second-order cone programming (SOCP) are presented. The two algor... Based on the ideas of infeasible interior-point methods and predictor-corrector algorithms, two interior-point predictor-corrector algorithms for the second-order cone programming (SOCP) are presented. The two algorithms use the Newton direction and the Euler direction as the predictor directions, respectively. The corrector directions belong to the category of the Alizadeh-Haeberly-Overton (AHO) directions. These algorithms are suitable to the cases of feasible and infeasible interior iterative points. A simpler neighborhood of the central path for the SOCP is proposed, which is the pivotal difference from other interior-point predictor-corrector algorithms. Under some assumptions, the algorithms possess the global, linear, and quadratic convergence. The complexity bound O(rln(εo/ε)) is obtained, where r denotes the number of the second-order cones in the SOCP problem. The numerical results show that the proposed algorithms are effective. 展开更多
关键词 second-order cone programming infeasible interior-point algorithm predictor-corrector algorithm global convergence complexity analysis
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ON A PROBLEM OF F.GROSS
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作者 方明亮 徐万松 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1995年第2期203-205,共3页
This paper deals with the problem of uniqueness of meromorphic functions with two deficient values and obtains a result which is an improvement of that of F.Gross and Yi Hongxun.
关键词 complex analysis meromorphic functions UNIQUENESS deficient value shared value
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THE MIGRATION SCHEME BASED ON SCHEMA THEOREM OF PGAs
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作者 GuanYu XuBaowen 《Journal of Electronics(China)》 2002年第3期315-319,共5页
Genetic Algorithms (GAs) are efficient non-gradient stochastic search methods and Parallel GAs (PGAs) are proposed to overcome the deficiencies of the sequential GAs, such as low speed, aptness to local convergence, e... Genetic Algorithms (GAs) are efficient non-gradient stochastic search methods and Parallel GAs (PGAs) are proposed to overcome the deficiencies of the sequential GAs, such as low speed, aptness to local convergence, etc. However, the tremendous increase in the communication costs accompanied with the parallelization stunts the further improvements of PGAs. This letter takes the decrease of the communication costs as the key to this problem and advances a new Migration Scheme based on Schema Theorem (MSST). MSST distills schemata from the populations and then proportionately disseminates them to other populations, which decreases the total communication cost among the populations and arms the multiple-population model with higher speed and better scalability. 展开更多
关键词 Parallel genetic algorithms Migration scheme Multiple-population model complexity analysis
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Evolution of IPv6 Internet topology with unusual sudden changes 被引量:6
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作者 艾均 赵海 +2 位作者 Kathleen M. Carley 苏湛 李辉 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第7期602-609,共8页
The evolution of Internet topology is not always smooth but sometimes with unusual sudden changes. Consequently, identifying patterns of unusual topology evolution is critical for Internet topology modeling and simula... The evolution of Internet topology is not always smooth but sometimes with unusual sudden changes. Consequently, identifying patterns of unusual topology evolution is critical for Internet topology modeling and simulation. We analyze IPv6 Internet topology evolution in IP-level graph to demonstrate how it changes in uncommon ways to restructure the Internet. After evaluating the changes of average degree, average path length, and some other metrics over time, we find that in the case of a large-scale growing the Internet becomes more robust; whereas in a top–bottom connection enhancement the Internet maintains its efficiency with links largely decreased. 展开更多
关键词 scale-free network Internet topology evolution unusual evolution of Internet topology complex network analysis
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Dynamic Response of Truss Adaptive Structures 被引量:1
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作者 ZHANG Lianwen XIA Renwei HUANG Hai 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2009年第6期849-855,共7页
It is pointed out that the damping matrix deduced by active members in the finite element vibration equation of a truss adaptive structure generally can not be decoupled, which leads to the difficulty in the process o... It is pointed out that the damping matrix deduced by active members in the finite element vibration equation of a truss adaptive structure generally can not be decoupled, which leads to the difficulty in the process of modal analysis by classical superposition method. This paper focuses on the computational method of the dynamic response for truss adaptive structures. Firstly, a new technique of state vector approach is applied to study the dynamic response of truss adaptive structures. It can make the coeffic lent matrix of first derivative of state vector a symmetric positive definite matrix, and particularly a diagonal matrix provided that mass matrix is derived by lumped method, so the coefficient matrix of the first derivative of state vector can be exactly decomposed by CHOLESKY method. In this case, the proposed technique not only improves the calculation accuracy, but also saves the computing time. Based on the procedure mentioned above, the mathematical formulation for the system response of truss adaptive structures is systematically derived in theory. Thirdly, by using FORTRAN language, a program system for computing dynamic response of truss adaptive structures is developed. Fourthly, a typical 18 bar space truss adaptive structure has been chosen as test numerical examples to show the feasibility and effectiveness of the proposed method. Finally, some good suggestions, such as how to choose complex mode shapes practically in determining the dynamic response are also given. The new approach can be extended to calculate the dynamic response of general adaptive structures. 展开更多
关键词 truss adaptive structure dynamic response active member complex modal analysis state vector approach
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Vibration of axially moving beam supported by viscoelastic foundation 被引量:1
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作者 Haijuan ZHANG Jian MA +1 位作者 Hu DING Liqun CHEN 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2017年第2期161-172,共12页
In this paper, transverse vibration of an axially moving beam supported by a viscoelastic foundation is analyzed by a complex modal analysis method. The equation of motion is developed based on the generalized Hamilto... In this paper, transverse vibration of an axially moving beam supported by a viscoelastic foundation is analyzed by a complex modal analysis method. The equation of motion is developed based on the generalized Hamilton's principle. Eigenvalues and eigenfunctions are semi-analytically obtained. The governing equation is represented in a canonical state space form, which is defined by two matrix differential operators. The orthogonality of the eigenfunctions and the adjoint eigenfunctions is used to decouple the system in the state space. The responses of the system to arbitrary external excitation and initial conditions are expressed in the modal expansion. Numerical examples are presented to illustrate the proposed approach. The effects of the foundation parameters on free and forced vibration are examined. 展开更多
关键词 axially moving beam viscoelastic foundation complex modal analysis natural frequency forced vibration
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Synthesis, Crystal Structure and Spectroscopic Properties of Zn(Ⅱ) with N-carbamylglutamate Ligand 被引量:2
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作者 舒绪刚 吴春丽 +2 位作者 万轲 张敏 吴信 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2015年第3期423-427,共5页
ZnC6HsN2O5H2O (NCGZn) has been synthesized, and its functional groups present in the title compound were confirmed by elemental analysis, TG and IR spectral studies. Meanwhile, the crystal of NCGZn was obtained by s... ZnC6HsN2O5H2O (NCGZn) has been synthesized, and its functional groups present in the title compound were confirmed by elemental analysis, TG and IR spectral studies. Meanwhile, the crystal of NCGZn was obtained by slow evaporation of a saturated aqueous solution at room temperature and confirmed by single-crystal X-ray diffraction analysis. It crystallizes in triclinic, space group P21 with a = 5.03220(1), b = 13.3747(4), c = 12.9944(4) A, β = 92.987(2)°, V= 873.39(4) A3, Z = 2, CI2H20NaOI2Zn2, Mr = 543.10, Dc = 2.065 g/cm3, F(000) = 552,μ(MoKa) = 2.826 mm-1, R = 0,0422 and wR = 0.1142. In NCGZn, Zn(l) and the symmetry formed Zn(l) ions are connected by five atoms from four NCG.2H anions and a water molecule. A NCG ligand has two carboxylate groups, one connecting a Zn ion, and the other bridgiong two Zn ions. The NCG ligand bridges four Zn ions through the amino group and two carboxylate groups with a water molecule to yield a 3D coordination polymer structure with hydrogen bonds. 展开更多
关键词 N-carbamylglutamate Zn(II) complex X-ray diffraction analysis structure
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