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Practical Research on Promoting the Reform of“One Field for One Household”in Guoyang County
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作者 HOU Limin 《Journal of Landscape Research》 2024年第1期83-85,90,共4页
In recent years,the problem of farmland fragmentation has become a major obstacle to the development of modern agriculture,and the reform of“one field for one household”can effectively sort out cultivated land resou... In recent years,the problem of farmland fragmentation has become a major obstacle to the development of modern agriculture,and the reform of“one field for one household”can effectively sort out cultivated land resources,increase contracted land area,improve land utilization rate,and effectively solve the problems of contracted land dispersion and farmland fragmentation in rural areas.This paper systematically anatomized the practice and effects of“one household,one field”reform in Guoyang County,analyzed the problems existing in the implementation process,and put forward corresponding suggestions and countermeasures,in order to provide experience and reference for the reform of one field in other regions. 展开更多
关键词 one field for each household Reform practice Guoyang County
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The Pancharatnam Phase of a Three-Level Atom Coupled to Two Systems of N-Two Level Atoms
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作者 D. A. M. Abo-Kahla 《Journal of Quantum Information Science》 2016年第1期44-55,共12页
In this paper, we present the analytical solution for the model that describes the interaction between a three-level atom and two systems of N-two level atoms. The effects of the quantum numbers and the coupling param... In this paper, we present the analytical solution for the model that describes the interaction between a three-level atom and two systems of N-two level atoms. The effects of the quantum numbers and the coupling parameters between spins on the Pancharatnam phase and the atomic inversion, for some special cases of the initial states, are investigated. The comparison between the two effects shows that the analytic results are well consistent. 展开更多
关键词 Pancharatnam Phase Atomic Inversion systems of N-two Level Atoms
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Industrial Structural Changes in Hong Kong,China under One Country,Two Systems Framework
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作者 Simon Xiaobin ZHAO Carola B RAMóN-BERJANO 《Chinese Geographical Science》 SCIE CSCD 2012年第3期302-318,共17页
Hong Kong has undergone substantial economic transformations and developed into a sophisticated busi- ness and financial center in the Asia-Pacific region, since the return of sovereignty to China as a Special Adminis... Hong Kong has undergone substantial economic transformations and developed into a sophisticated busi- ness and financial center in the Asia-Pacific region, since the return of sovereignty to China as a Special Administrative Region under the One Country Two Systems (OCTS) in 1997. This paper discusses and analyzes the industrial struc- tural changes of Hong Kong in recent decades as well as its future challenges and opportunities, The data and finding reveal that even though Hong Kong will face fierce competition from the Mainland's cities as the rise of China, the important role as a bridge between China and the rest of the world wilt brace Hong Kong itself under the OCTS for developing into a service hub for business and trade in the Asia-Pacific region. 展开更多
关键词 economic transformation Hong Kong industrial structural changes one Country two systems
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Finite-time Prescribed Performance Time-Varying Formation Control for Second-Order Multi-Agent Systems With Non-Strict Feedback Based on a Neural Network Observer 被引量:1
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作者 Chi Ma Dianbiao Dong 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第4期1039-1050,共12页
This paper studies the problem of time-varying formation control with finite-time prescribed performance for nonstrict feedback second-order multi-agent systems with unmeasured states and unknown nonlinearities.To eli... This paper studies the problem of time-varying formation control with finite-time prescribed performance for nonstrict feedback second-order multi-agent systems with unmeasured states and unknown nonlinearities.To eliminate nonlinearities,neural networks are applied to approximate the inherent dynamics of the system.In addition,due to the limitations of the actual working conditions,each follower agent can only obtain the locally measurable partial state information of the leader agent.To address this problem,a neural network state observer based on the leader state information is designed.Then,a finite-time prescribed performance adaptive output feedback control strategy is proposed by restricting the sliding mode surface to a prescribed region,which ensures that the closed-loop system has practical finite-time stability and that formation errors of the multi-agent systems converge to the prescribed performance bound in finite time.Finally,a numerical simulation is provided to demonstrate the practicality and effectiveness of the developed algorithm. 展开更多
关键词 Finite-time control multi-agent systems neural network prescribed performance control time-varying formation control
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Exponential stabilization of networked control systems and design of switching controller 被引量:5
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作者 Dan MA Jun ZHAO 《控制理论与应用(英文版)》 EI 2006年第1期96-101,共6页
This paper deals with the problem of switching between an open-loop estimator and a close-loop estimator for compensating transmission error and packet dropout of networked control systems. Switching impulse is consid... This paper deals with the problem of switching between an open-loop estimator and a close-loop estimator for compensating transmission error and packet dropout of networked control systems. Switching impulse is considered in order to reduce the error between theory and application, a sufficient condition for exponential stabilization of networked control systems under a given switching rule is presented by multiple Lyapunov-like functions. These results are presented for both continuous-time and discrete-time domains. Controllers are designed by means of linear matrix inequalities. Sim- ulation results show the feasibility and efficiency of the proposed method. 展开更多
关键词 Networked control systems DROPOUT Switching controller Reset map matrix Multiple Lyapunov-like functions Exponential stabilization
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Reliability analysis of monotone coherent multi-state systems based on Bayesian networks 被引量:2
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作者 Binghua Song Zhongbao Zhou +2 位作者 Chaoqun Ma Jinglun Zhou Shaofeng Geng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2016年第6期1326-1335,共10页
The Bayesian networks (BNs) provide a robust probabilistic method of reasoning under uncertainty and have been successfully applied to a variety of real-world tasks. Aiming to explore the capabilities of the BN formal... The Bayesian networks (BNs) provide a robust probabilistic method of reasoning under uncertainty and have been successfully applied to a variety of real-world tasks. Aiming to explore the capabilities of the BN formalism in reliability analysis of monotone coherent multi-state systems, the BNs are compared with a popular tool for reliability analysis of monotone coherent multi-state systems, namely the multi-state fault trees (MFTs). It is shown that any MFT can be directly mapped into BN and the basic inference techniques on the latter may be used to obtain classical parameters computed from the former (i.e. probability distribution of top variable, minimal upper vectors and maximum lower vectors for any performance level, importance measures of components). Furthermore, some additional information can be obtained by using BN, both at the modeling and analysis level. At the modeling level, several restrictive assumptions implicit in the MFT methodology can be removed and various kinds of dependencies among components can be accommodated. At the analysis level, a general diagnostic analysis can be performed. The comparison of these methods is illustrated by an example of the water supply system. © 2016 Beijing Institute of Aerospace Information. 展开更多
关键词 Bayesian networks Probability distributions RELIABILITY Reliability theory VECTORS Water supply Water supply systems
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Observer-based dynamic event-triggered control for distributed parameter systems over mobile sensor-plus-actuator networks
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作者 穆文英 庄波 邱芳 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期237-243,共7页
We develop a policy of observer-based dynamic event-triggered state feedback control for distributed parameter systems over a mobile sensor-plus-actuator network.It is assumed that the mobile sensing devices that prov... We develop a policy of observer-based dynamic event-triggered state feedback control for distributed parameter systems over a mobile sensor-plus-actuator network.It is assumed that the mobile sensing devices that provide spatially averaged state measurements can be used to improve state estimation in the network.For the purpose of decreasing the update frequency of controller and unnecessary sampled data transmission, an efficient dynamic event-triggered control policy is constructed.In an event-triggered system, when an error signal exceeds a specified time-varying threshold, it indicates the occurrence of a typical event.The global asymptotic stability of the event-triggered closed-loop system and the boundedness of the minimum inter-event time can be guaranteed.Based on the linear quadratic optimal regulator, the actuator selects the optimal displacement only when an event occurs.A simulation example is finally used to verify that the effectiveness of such a control strategy can enhance the system performance. 展开更多
关键词 distributed parameter systems event-triggered control mobile sensors mobile actuators
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A Review of Generative Adversarial Networks for Intrusion Detection Systems: Advances, Challenges, and Future Directions
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作者 Monirah Al-Ajlan Mourad Ykhlef 《Computers, Materials & Continua》 SCIE EI 2024年第11期2053-2076,共24页
The ever-growing network traffic threat landscape necessitates adopting accurate and robust intrusion detection systems(IDSs).IDSs have become a research hotspot and have seen remarkable performance improvements.Gener... The ever-growing network traffic threat landscape necessitates adopting accurate and robust intrusion detection systems(IDSs).IDSs have become a research hotspot and have seen remarkable performance improvements.Generative adversarial networks(GANs)have also garnered increasing research interest recently due to their remarkable ability to generate data.This paper investigates the application of(GANs)in(IDS)and explores their current use within this research field.We delve into the adoption of GANs within signature-based,anomaly-based,and hybrid IDSs,focusing on their objectives,methodologies,and advantages.Overall,GANs have been widely employed,mainly focused on solving the class imbalance issue by generating realistic attack samples.While GANs have shown significant potential in addressing the class imbalance issue,there are still open opportunities and challenges to be addressed.Little attention has been paid to their applicability in distributed and decentralized domains,such as IoT networks.Efficiency and scalability have been mostly overlooked,and thus,future works must aim at addressing these gaps. 展开更多
关键词 Intrusion detection systems network security generative networks deep learning DATASET
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Exponential networked synchronization of master-slave chaotic systems with timevarying communication topologies 被引量:1
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作者 杨东升 刘振伟 +1 位作者 赵琰 刘兆冰 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第4期151-158,共8页
The networked synchronization problem of a class of master-slave chaotic systems with time-varying communication topologies is investigated in this paper. Based on algebraic graph theory and matrix theory, a simple li... The networked synchronization problem of a class of master-slave chaotic systems with time-varying communication topologies is investigated in this paper. Based on algebraic graph theory and matrix theory, a simple linear state feedback controller is designed to synchronize the master chaotic system and the slave chaotic systems with a time- varying communication topology connection. The exponential stability of the closed-loop networked synchronization error system is guaranteed by applying Lyapunov stability theory. The derived novel criteria are in the form of linear matrix inequalities (LMIs), which are easy to examine and tremendously reduce the computation burden from the feedback matrices. This paper provides an alternative networked secure communication scheme which can be extended conveniently. An illustrative example is given to demonstrate the effectiveness of the proposed networked synchronization method. 展开更多
关键词 exponential networked synchronization master-slave chaotic systems algebraic graph theory communication topology
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Physical Layer Security of 6G Vehicular Networks with UAV Systems:First Order Secrecy Metrics,Optimization,and Bounds
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作者 Sagar Kavaiya Hiren Mewada +3 位作者 Sagarkumar Patel Dharmendra Chauhan Faris A.Almalki Hana Mohammed Mujlid 《Computers, Materials & Continua》 SCIE EI 2024年第9期3685-3711,共27页
The mobility and connective capabilities of unmanned aerial vehicles(UAVs)are becoming more and more important in defense,commercial,and research domains.However,their open communication makes UAVs susceptible toundes... The mobility and connective capabilities of unmanned aerial vehicles(UAVs)are becoming more and more important in defense,commercial,and research domains.However,their open communication makes UAVs susceptible toundesirablepassive attacks suchas eavesdroppingor jamming.Recently,the inefficiencyof traditional cryptography-based techniques has led to the addition of Physical Layer Security(PLS).This study focuses on the advanced PLS method for passive eavesdropping in UAV-aided vehicular environments,proposing a solution to complement the conventional cryptography approach.Initially,we present a performance analysis of first-order secrecy metrics in 6G-enabled UAV systems,namely hybrid outage probability(HOP)and secrecy outage probability(SOP)over 2×2 Nakagami-m channels.Later,we propose a novel technique for mitigating passive eavesdropping,which considers first-order secrecy metrics as an optimization problem and determines their lower and upper bounds.Finally,we conduct an analysis of bounded HOP and SOP using the interactive Nakagami-m channel,considering the multiple-input-multiple-output configuration of the UAV system.The findings indicate that 2×2 Nakagami-mis a suitable fadingmodel under constant velocity for trustworthy receivers and eavesdroppers.The results indicate that UAV mobility has some influence on an eavesdropper’s intrusion during line-of-sight-enabled communication and can play an important role in improving security against passive eavesdroppers. 展开更多
关键词 Physical layer security 3D positioning 6G communications UAV systems
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A Variational Approach for Numerically Solving the Two-Component Radial Dirac Equation for One-Particle Systems 被引量:2
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作者 Antonio L. A. Fonseca Daniel L. Nascimento +1 位作者 Fabio F. Monteiro Marco A. Amato 《Journal of Modern Physics》 2012年第4期350-354,共5页
In this paper we propose a numerical approach to solve the relativistic Dirac equation suitable for computational calculations of one-electron systems. A variational procedure is carried out similar to the well-known ... In this paper we propose a numerical approach to solve the relativistic Dirac equation suitable for computational calculations of one-electron systems. A variational procedure is carried out similar to the well-known Hylleraas computational method. An application of the method to hydrogen isoelectronic atoms is presented, showing its consistency and high accuracy, relative to the exact analytical eigenvalues. 展开更多
关键词 one-ELECTRON systems 2D DIRAC Equation No-Inertial Frames Variational Approach
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Reviewing Stability Criteria for Positive Homogeneous Systems and Adding One for Discrete-Time Cases with Degree Less Than One
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作者 Nguyen Quang Tuan 《Circuits and Systems》 2024年第1期1-11,共11页
The article synthesizes and presents the results regarding the stability of positive homogeneous systems that have been researched and published in recent years. Next, we provide a sufficient condition for global expo... The article synthesizes and presents the results regarding the stability of positive homogeneous systems that have been researched and published in recent years. Next, we provide a sufficient condition for global exponential stability in the case of discrete-time positive homogeneous systems with an order less than one with time-varying delays. 展开更多
关键词 Exponential Stability Homogeneous systems Positive systems Positive Homogeneous systems
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The First Five Years of a Phase Theory for Complex Systems and Networks
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作者 Dan Wang Wei Chen Li Qiu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第8期1728-1743,共16页
In this paper,we review the development of a phase theory for systems and networks in its first five years,represented by a trilogy:Matrix phases and their properties;The MIMO LTI system phase response,its physical in... In this paper,we review the development of a phase theory for systems and networks in its first five years,represented by a trilogy:Matrix phases and their properties;The MIMO LTI system phase response,its physical interpretations,the small phase theorem,and the sectored real lemma;The synchronization of a multi-agent network using phase alignment.Towards the end,we also summarize a list of ongoing research on the phase theory and speculate what will happen in the next five years. 展开更多
关键词 Consensus and synchronization matrix phases multi-agent systems phase theory sectored real lemma small phase theorem.
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Exponential stability for networked control systems based on the model of nonlinear discrete-time system with time-varying delay 被引量:1
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作者 HUANGJian GUANZhihong WANGZhongdong 《Journal of Chongqing University》 CAS 2004年第1期30-33,共4页
An uncertain nonlinear discrete-time system model with time-varying input delays for networked control systems (NCSs) is presented. The problem of exponential stability for the system is considered and some new criter... An uncertain nonlinear discrete-time system model with time-varying input delays for networked control systems (NCSs) is presented. The problem of exponential stability for the system is considered and some new criteria of exponential stability are obtained based on norm inequality methods. A numerical example is given todemonstrate that those criteria are useful to analyzing the stability of nonlinear NCSs. 展开更多
关键词 networked control systems nonlinear discrete-time system time-varying delay exponential stability
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Fuzzy-Model-Based Finite Frequency Fault Detection Filtering Design for Two-Dimensional Nonlinear Systems
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作者 Meng Wang Huaicheng Yan +1 位作者 Jianbin Qiu Wenqiang Ji 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第10期2099-2110,共12页
This article studies the fault detection filtering design problem for Roesser type two-dimensional(2-D)nonlinear systems described by uncertain 2-D Takagi-Sugeno(T-S)fuzzy models.Firstly,fuzzy Lyapunov functions are c... This article studies the fault detection filtering design problem for Roesser type two-dimensional(2-D)nonlinear systems described by uncertain 2-D Takagi-Sugeno(T-S)fuzzy models.Firstly,fuzzy Lyapunov functions are constructed and the 2-D Fourier transform is exploited,based on which a finite frequency fault detection filtering design method is proposed such that a residual signal is generated with robustness to external disturbances and sensitivity to faults.It has been shown that the utilization of available frequency spectrum information of faults and disturbances makes the proposed filtering design method more general and less conservative compared with a conventional nonfrequency based filtering design approach.Then,with the proposed evaluation function and its threshold,a novel mixed finite frequency H_(∞)/H_(-)fault detection algorithm is developed,based on which the fault can be immediately detected once the evaluation function exceeds the threshold.Finally,it is verified with simulation studies that the proposed method is effective and less conservative than conventional non-frequency and/or common Lyapunov function based filtering design methods. 展开更多
关键词 Fault diagnosis finite frequency specifications mixed H_(∞)/H_(-)performance two-dimensional nonlinear systems
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Weighted Forwarding in Graph Convolution Networks for Recommendation Information Systems
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作者 Sang-min Lee Namgi Kim 《Computers, Materials & Continua》 SCIE EI 2024年第2期1897-1914,共18页
Recommendation Information Systems(RIS)are pivotal in helping users in swiftly locating desired content from the vast amount of information available on the Internet.Graph Convolution Network(GCN)algorithms have been ... Recommendation Information Systems(RIS)are pivotal in helping users in swiftly locating desired content from the vast amount of information available on the Internet.Graph Convolution Network(GCN)algorithms have been employed to implement the RIS efficiently.However,the GCN algorithm faces limitations in terms of performance enhancement owing to the due to the embedding value-vanishing problem that occurs during the learning process.To address this issue,we propose a Weighted Forwarding method using the GCN(WF-GCN)algorithm.The proposed method involves multiplying the embedding results with different weights for each hop layer during graph learning.By applying the WF-GCN algorithm,which adjusts weights for each hop layer before forwarding to the next,nodes with many neighbors achieve higher embedding values.This approach facilitates the learning of more hop layers within the GCN framework.The efficacy of the WF-GCN was demonstrated through its application to various datasets.In the MovieLens dataset,the implementation of WF-GCN in LightGCN resulted in significant performance improvements,with recall and NDCG increasing by up to+163.64%and+132.04%,respectively.Similarly,in the Last.FM dataset,LightGCN using WF-GCN enhanced with WF-GCN showed substantial improvements,with the recall and NDCG metrics rising by up to+174.40%and+169.95%,respectively.Furthermore,the application of WF-GCN to Self-supervised Graph Learning(SGL)and Simple Graph Contrastive Learning(SimGCL)also demonstrated notable enhancements in both recall and NDCG across these datasets. 展开更多
关键词 Deep learning graph neural network graph convolution network graph convolution network model learning method recommender information systems
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Experimental and Simulation Analysis of Two-Tone and Three-Tone Photodetector Linearity Characterizing Systems 被引量:1
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作者 费嘉瑞 黄永清 +3 位作者 刘悠欣 刘凯 段晓峰 任晓敏 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第11期110-113,共4页
Two measurement techniques are investigated to characterize photodetector linearity. A model for the two-tone and three-tone photodetector systems is developed to thoroughly investigate the influences of setup compone... Two measurement techniques are investigated to characterize photodetector linearity. A model for the two-tone and three-tone photodetector systems is developed to thoroughly investigate the influences of setup components on the measurement results. We demonstrate that small bias shifts from the quadrature point of the modulator will induce deviation into measurement results of the two-tone system, and the simulation results correspond well to experimental and calculation results. 展开更多
关键词 OIP Experimental and Simulation Analysis of two-Tone and Three-Tone Photodetector Linearity Characterizing systems IMD dBm
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Adoption of Solar Pumping Systems by Vegetable Farmers in Niayes Agro-Ecological Zone of Senegal: Adoption as a Sequential Process
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作者 Abou Abdoulaye Sow Papa Yona Boubacar Mane +1 位作者 Mamma Sawaneh Halidou Kafando 《Journal of Power and Energy Engineering》 2024年第9期19-36,共18页
This article examines the determinants of the adoption of solar pumping systems (PV) by vegetable farmers in the Niayes area of Senegal. To measure the determinants, we used a sequential logit model to translate the a... This article examines the determinants of the adoption of solar pumping systems (PV) by vegetable farmers in the Niayes area of Senegal. To measure the determinants, we used a sequential logit model to translate the adoption process from becoming aware of solar pumping systems to testing them, i.e. using them at least once, and then continuing to use them over time. The results show that the main variables affecting awareness of the use of solar pumping systems (PV) are age, marital status, experience, access to credit, the farmer’s knowledge of climate change, the farmer’s origin in the Thiès region and length of time in the Niayes area. The first use of PVs is influenced by factors such as the size of the plot, the distance of the plot from the main road or from the market. Finally, the decision to adopt or continue use is influenced by gender, experience, household size and access to credit. Surprisingly, access to credit does not affect the first use of solar pumping systems, but plays a key role in their continued use. 展开更多
关键词 Solar Pumping systems ADOPTION Vegetable Cultivation Niayes (Senegal)
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A novel strategy of smart manipulation by micro-scale oscillatory networks of the reactionary zones for enhanced extreme thrust control of the next-generation solid propulsion systems
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作者 Alexander N.Lukin 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2018年第5期635-642,共8页
The main aim of this research is to get a better knowledge and understanding of the micro-scale oscillatory networks behavior in the solid propellants reactionary zones. Fundamental understanding of the micro-and nano... The main aim of this research is to get a better knowledge and understanding of the micro-scale oscillatory networks behavior in the solid propellants reactionary zones. Fundamental understanding of the micro-and nano-scale combustion mechanisms is essential to the development and further improvement of the next-generation technologies for extreme control of the solid propellant thrust. Both experiments and theory confirm that the micro-and nano-scale oscillatory networks excitation in the solid propellants reactionary zones is a rather universal phenomenon. In accordance with our concept,the micro-and nano-scale structures form both the fractal and self-organized wave patterns in the solid propellants reactionary zones. Control by the shape, the sizes and spacial orientation of the wave patterns allows manipulate by the energy exchange and release in the reactionary zones. A novel strategy for enhanced extreme thrust control in solid propulsion systems are based on manipulation by selforganization of the micro-and nano-scale oscillatory networks and self-organized patterns formation in the reactionary zones with use of the system of acoustic waves and electro-magnetic fields, generated by special kind of ring-shaped electric discharges along with resonance laser radiation. Application of special kind of the ring-shaped electric discharges demands the minimum expenses of energy and opens prospects for almost inertia-free control by combustion processes. Nano-sized additives will enhance self-organizing and self-synchronization of the micro-and nano-scale oscillatory networks on the nanometer scale. Suggested novel strategy opens the door for completely new ways for enhanced extreme thrust control of the solid propulsion systems. 展开更多
关键词 Solid propulsion systems EXTREME thrust control Reactionary ZoneS MICRO-SCALE OSCILLATORY NEtwoRKS Self-organized wave patterns Energy-releasing areas
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Two Households——One Family
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作者 遐思 《语言教育》 1990年第3期25-27,共3页
I was nine when my parents told me they were separating.Even my sister Meghan, then seven and my brother Patrick, then foursensed that something was wrong between our parents. At fisrt, Momand Dad tried not to argue i... I was nine when my parents told me they were separating.Even my sister Meghan, then seven and my brother Patrick, then foursensed that something was wrong between our parents. At fisrt, Momand Dad tried not to argue in front of us, but we saw that they hadtalked to each other less-and they got mad ot us for everything. 展开更多
关键词 PARENTS something FAMILY everything BROTHER argue two households WRONG SISTER tried
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