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Tao Xue, Zi-wei Wang, Tao Zhang, Ou Bai, Meng Zhang, Bin Han,taozhang@tsinghua.edu.cn
Frontiers of Information Technology & Electronic Engineering 2020, Volume 21, Issue 5, Pages 649-808 doi: 10.1631/FITEE.1900418
The Method and Formula for Stability Factor of Slope with State of Soil Original Stress
Wang Guoti
Strategic Study of CAE 2006, Volume 8, Issue 12, Pages 80-84
The methods for analysis of stability of slope are usually considered, developed and improved along the line of finite slice method. But the safety factor of stability is facing challenge in engineering application. Because of the state of original stress in soil is ignored and disfigurement of finite slice method is in existence at all time. In different conditions of soil consolidation, K0, the lateral stress coefficient of soil state, has influenced the property of soil and excavation of slope. In this paper, in consideration of the state of soil original stress, the calculating formula for safety factor have been given with applying Coulomb's equation for shear strength of soil and Mohr - Coulomb rule. There are many examples of safety factor using the formula of this paper, which have been calculated and compared with finite slice methods selected from reference literatures. The formula have showed their clear concept, simple calculation and dependable result. They can be used in engineering.
Keywords: ateral stress coefficient K0 state of original stress formula of safety factor of stability
A Laboratorial Method for Determining Incipient Yield Pressure of Thick Wall Cylinder
Zhang Yuxian’,Liao Zhenfang,Wang Hong ,Pei Jianghong
Strategic Study of CAE 2005, Volume 7, Issue 11, Pages 72-75
Based on the relation between the incipient yield pressure and the limit of yielding in cylinder according to the elastic disabled rule, a laboratorial method of determining the incipient yield pressure is designed and a set of experimental data were gained. The incipient yield pressure of the cylinder is gained by analyzing the experimental data. The laboratorial method has a good reliability as the experimental value has a little error to the theory value.
Keywords: thick wall cylinder disabled incipient yield pressure
Theory and Method of Power System Integrated Security Region Irrelevant to Operation States: An Introduction Feature Article
Yixin Yu, Yanli Liu, Chao Qin, Tiankai Yang
Engineering 2020, Volume 6, Issue 7, Pages 754-777 doi: 10.1016/j.eng.2019.11.016
How to comprehensively consider the power flow constraints and various stability constraints in a series of power system optimization problems without affecting the calculation speed is always a problem. The computational burden of probabilistic security assessment is even more unimaginable. In order to solve such problems, a security region (SR) methodology is proposed, which is a brand-new methodology developed on the basis of the classical point-wise method. Tianjin University has been studying the SR methodology since the 1980s, and has achieved a series of original breakthroughs that are described in this paper. The integrated SR introduced in this paper is mainly defined in the power injection space, and includes SRs to ensure steady-state security, transient stability, static voltage stability, and small disturbance stability. These SRs are uniquely determined for a given network topology (as well as location and clearing process for transient faults) and given system component parameters, and are irrelevant to operation states. This paper presents 11 facts and related remarks to introduce the basic concepts, composition, dynamics nature, and topological and geometric characteristics of SRs. It also provides a practical mathematical description of SR boundaries and fast calculation methods to determine them in a concise and systematic way. Thus, this article provides support for the systematic understanding, future research, and applications of SRs. The most critical finding on the topological and geometric characteristics of SRs is that, within the scope of engineering concern, the practical boundaries of SRs in the power injection space can be approximated by one or a few hyperplanes. Based on this finding, the calculation time for power system probabilistic security assessment (i.e., risk analysis) and power system optimization with security constraints can be decreased by orders of magnitude.
Keywords: Security region Composition Power flow security Static voltage stability Small-disturbance stability Transient stability Dynamics nature Topological and geometric characteristics Hyperplane
Illuminating the new method process of slope stability analysis by soil stress state
Wang Guoti,Wang Wandi
Strategic Study of CAE 2010, Volume 12, Issue 1, Pages 52-55
According to the soil stress state and calculation method of slope stability coefficient, and combined with soil properties, this paper illuminated basic assumption, formula derivation process and project application in detail. As the calculation formula of slope stability coefficient's theory analysis is rigorous, and the derived formula is correct, the project application is reliable. This paper will provide reference for relative project application and further research.
Keywords: slope stability analysis method stress state slope stability coefficient
A matrix-based static approach to analysis of finite state machines Research Article
He DENG, Yongyi YAN, Zengqiang CHEN,yyyan@mail.nankai.edu.cn
Frontiers of Information Technology & Electronic Engineering 2022, Volume 23, Issue 8, Pages 1239-1246 doi: 10.1631/FITEE.2100561
Keywords: Logical systems Finite-valued systems Semi-tensor product of matrices Finite state machines Matrix approaches
Coherence analysis and Laplacian energy of recursive trees with controlled initial states Research Articles
Mei-du Hong, Wei-gang Sun, Su-yu Liu, Teng-fei Xuan,wgsun@hdu.edu.cn
Frontiers of Information Technology & Electronic Engineering 2020, Volume 21, Issue 6, Pages 809-962 doi: 10.1631/FITEE.1900133
Keywords: 一致性;网络一致性;拉普拉斯能量
Weichao Yue、 Weihua Gui、 Xiaofang Chen、 Zhaohui Zeng、 Yongfang Xie
Engineering 2019, Volume 5, Issue 6, Pages 1060-1076 doi: 10.1016/j.eng.2019.10.005
In the aluminum reduction process, aluminum fluoride (AlF3) is added to lower the liquidus temperature of the electrolyte and increase the electrolytic efficiency. Making the decision on the amount of AlF3 addition (referred to in this work as MDAAA) is a complex and knowledge-based task that must take into consideration a variety of interrelated functions; in practice, this decision-making step is performed manually. Due to technician subjectivity and the complexity of the aluminum reduction cell, it is difficult to guarantee the accuracy of MDAAA based on knowledge-driven or data-driven methods alone. Existing strategies for MDAAA have difficulty covering these complex causalities. In this work, a data and knowledge collaboration strategy for MDAAA based on augmented fuzzy cognitive maps (FCMs) is proposed. In the proposed strategy, the fuzzy rules are extracted by extended fuzzy k-means (EFKM) and fuzzy decision trees, which are used to amend the initial structure provided by experts. The state transition algorithm (STA) is introduced to detect weight matrices that lead the FCMs to desired steady states. This study then experimentally compares the proposed strategy with some existing research. The results of the comparison show that the speed of FCMs convergence into a stable region based on the STA using the proposed strategy is faster than when using the differential Hebbian learning (DHL), particle swarm optimization (PSO), or genetic algorithm (GA) strategies. In addition, the accuracy of MDAAA based on the proposed method is better than those based on other methods. Accordingly, this paper provides a feasible and effective strategy for MDAAA.
Keywords: AlF 3 addition Fuzzy cognitive maps Learning algorithms State transition algorithm Fuzzy decision trees
Study on evaluation method of weapon equipment readiness
Yu Xiang,Du Gang and He Qiwei
Strategic Study of CAE 2015, Volume 17, Issue 5, Pages 76-82
Weapon equipment readiness evaluation is important for the meticulous and scientific usage management and maintenance support of weapon equipment. However, the current evaluation methods don’t fit the new situation and new requirements in terms of timeliness, accuracy and task matching. Therefore, an improved evaluation method for weapon equipment readiness based on the technical status of the main onboard machinery was presented. Through the simulation evaluation of the readiness for a certain type of destroyer, the feasibility of this method was verified, and some countermeasures and suggestions to further improve the method and mechanism for equipment readiness evaluation were proposed.
Keywords: equipment readiness;technical status;maintenance support of equipment;countermeasures
Multi-AUV SOM task allocation algorithm considering initial orientation and ocean current environment Special Feature on Intelligent Robats
Da-qi ZHU, Yun QU, Simon X. YANG
Frontiers of Information Technology & Electronic Engineering 2019, Volume 20, Issue 3, Pages 330-341 doi: 10.1631/FITEE.1800562
There is an ocean current in the actual underwater working environment. An improved self-organizing neural network task allocation model of multiple autonomous underwater vehicles (AUVs) is proposed for a three-dimensional underwater workspace in the ocean current. Each AUV in the model will be competed, and the shortest path under an ocean current and different azimuths will be selected for task assignment and path planning while guaranteeing the least total consumption. First, the initial position and orientation of each AUV are determined. The velocity and azimuths of the constant ocean current are determined. Then the AUV task assignment problem in the constant ocean current environment is considered. The AUV that has the shortest path is selected for task assignment and path planning. Finally, to prove the effectiveness of the proposed method, simulation results are given.
Keywords: Autonomous underwater vehicles Self-organizing neural networks Azimuths Ocean current
A Hierarchical-Based Initialization Method for K-Means Algorithm
Tang Jiubin,Lu Jianfeng,Tang Zhenmin, Yang Jingyu
Strategic Study of CAE 2007, Volume 9, Issue 11, Pages 74-79
K-means algorithm is one of common clustering algorithms, but the cluster center initialization is a hard problem. In this paper, a hierarchical-based initialization approach is proposed for K-Means algorithm. The general clustering problem is treated as weighted clustering problem, the original data is sampled level by level to reduce the data amount. Then clustering is carried out at each level by top-down. The initial center of each level is mapped from the clustering center of upper level and this procedure is repeated until the original data level is reached. As a result, the initial center for the original data is obtained. Both the experimental results on simulated data and real data show that the proposed method has high converging speed, high quality of clustering and is insensitive to noise, which is superior to some existing clustering algorithms.
Keywords: hierarchical technique initial cluster centers weighted data K-means clustering
Distribution system state estimation: an overview of recent developments Review Article
Gang WANG, Georgios B. GIANNAKIS, Jie CHEN, Jian SUN
Frontiers of Information Technology & Electronic Engineering 2019, Volume 20, Issue 1, Pages 4-17 doi: 10.1631/FITEE.1800590
In the envisioned smart grid, high penetration of uncertain renewables, unpredictable participation of (industrial) customers, and purposeful manipulation of smart meter readings, all highlight the need for accurate, fast, and robust power system state estimation (PSSE). Nonetheless, most real-time data available in the current and upcoming transmission/distribution systems are nonlinear in power system states (i.e., nodal voltage phasors). Scalable approaches to dealing with PSSE tasks undergo a paradigm shift toward addressing the unique modeling and computational challenges associated with those nonlinear measurements. In this study, we provide a contemporary overview of PSSE and describe the current state of the art in the nonlinear weighted least-squares and least-absolutevalue PSSE. To benchmark the performance of unbiased estimators, the Cramér-Rao lower bound is developed. Accounting for cyber attacks, new corruption models are introduced, and robust PSSE approaches are outlined as well. Finally, distribution system state estimation is discussed along with its current challenges. Simulation tests corroborate the effectiveness of the developed algorithms as well as the practical merits of the theory.
Keywords: State estimation Cramér-Rao bound Feasible point pursuit Semidefinite relaxation Proximal linear algorithm Composite optimization Cyber attack Bad data detection
Yang Jun,Yang Zhi,Zhang Guodong,Tang Yunwei and Chen Hongping
Strategic Study of CAE 2014, Volume 16, Issue 2, Pages 73-78
Through the indoor free load swelling rate test,Yichang City,a section of a highway reconstruction project of expansive soil were studied. Key analysis free load swelling rate of a non-load time,the proportion of mixed sand,the relationship between the initial dry density, experimental studies have shown that:Free load swelling rate is mainly divided into rapid expansion,slow expansion and eventually stabilize in three stages;during the initial dry density is constant,weathered sand soil free load swelling rate will increase the proportion of sand mixed with the rapid decrease slowly after the first lower,weathered sand soil modified free load swelling rate is not sensitive to the amount of sand mixed;in the same mixed sand ratio, weathered sand soil free load swelling rate increases with increasing initial dry density increases rapidly between them have a good linear correlation,expansive soil subgrade construction in progress when control of the initial dry density,to help reduce its swelling deformation,ensuring the stability of embankment.
Keywords: expansive soils weathered sand initial dry density mixing sand ratio free load swelling rate
Visual interactive image clustering: a target-independent approach for configuration optimization in machine vision measurement Research Article
Lvhan PAN, Guodao SUN, Baofeng CHANG, Wang XIA, Qi JIANG, Jingwei TANG, Ronghua LIANG
Frontiers of Information Technology & Electronic Engineering 2023, Volume 24, Issue 3, Pages 355-372 doi: 10.1631/FITEE.2200547
Keywords: Machine vision measurement Lighting scheme design Parameter optimization Visual interactive image clustering
Bing TIAN,Qun-tao AN,Li SUN,Dong-yang SUN,Jian-dong DUAN
Frontiers of Information Technology & Electronic Engineering 2016, Volume 17, Issue 8, Pages 803-813 doi: 10.1631/FITEE.1500298
Keywords: Surface permanent magnet synchronous motor (SPMSM) Initial position estimation Nonlinear model Hybrid injection Position observer
Title Author Date Type Operation
Fixed-time constrained acceleration reconstruction scheme for robotic exoskeleton via neural networks
Tao Xue, Zi-wei Wang, Tao Zhang, Ou Bai, Meng Zhang, Bin Han,taozhang@tsinghua.edu.cn
Journal Article
The Method and Formula for Stability Factor of Slope with State of Soil Original Stress
Wang Guoti
Journal Article
A Laboratorial Method for Determining Incipient Yield Pressure of Thick Wall Cylinder
Zhang Yuxian’,Liao Zhenfang,Wang Hong ,Pei Jianghong
Journal Article
Theory and Method of Power System Integrated Security Region Irrelevant to Operation States: An Introduction
Yixin Yu, Yanli Liu, Chao Qin, Tiankai Yang
Journal Article
Illuminating the new method process of slope stability analysis by soil stress state
Wang Guoti,Wang Wandi
Journal Article
A matrix-based static approach to analysis of finite state machines
He DENG, Yongyi YAN, Zengqiang CHEN,yyyan@mail.nankai.edu.cn
Journal Article
Coherence analysis and Laplacian energy of recursive trees with controlled initial states
Mei-du Hong, Wei-gang Sun, Su-yu Liu, Teng-fei Xuan,wgsun@hdu.edu.cn
Journal Article
A Data and Knowledge Collaboration Strategy for Decision-Making on the Amount of Aluminum Fluoride Addition Based on Augmented Fuzzy Cognitive Maps
Weichao Yue、 Weihua Gui、 Xiaofang Chen、 Zhaohui Zeng、 Yongfang Xie
Journal Article
Study on evaluation method of weapon equipment readiness
Yu Xiang,Du Gang and He Qiwei
Journal Article
Multi-AUV SOM task allocation algorithm considering initial orientation and ocean current environment
Da-qi ZHU, Yun QU, Simon X. YANG
Journal Article
A Hierarchical-Based Initialization Method for K-Means Algorithm
Tang Jiubin,Lu Jianfeng,Tang Zhenmin, Yang Jingyu
Journal Article
Distribution system state estimation: an overview of recent developments
Gang WANG, Georgios B. GIANNAKIS, Jie CHEN, Jian SUN
Journal Article
Experimental research on the mixed sand ratio and initial dry density of weathered sand improved expansive soil free load swelling rate
Yang Jun,Yang Zhi,Zhang Guodong,Tang Yunwei and Chen Hongping
Journal Article
Visual interactive image clustering: a target-independent approach for configuration optimization in machine vision measurement
Lvhan PAN, Guodao SUN, Baofeng CHANG, Wang XIA, Qi JIANG, Jingwei TANG, Ronghua LIANG
Journal Article