期刊文献+
共找到40篇文章
< 1 2 >
每页显示 20 50 100
连词“无论”语法化的机制与诱因 被引量:1
1
作者 程亚恒 《长春师范大学学报(人文社会科学版)》 2014年第1期65-69,共5页
“无论”是现代汉语中使用频率很高的一个连词。它经常放在一个短语或句子前面,引出一些条件。连词“无论”出现于隋唐时期,是上古汉语的跨层结构“无论”(又写作“毋论”、“勿论”)在历史发展过程中不断语法化和词汇化的结果。双... “无论”是现代汉语中使用频率很高的一个连词。它经常放在一个短语或句子前面,引出一些条件。连词“无论”出现于隋唐时期,是上古汉语的跨层结构“无论”(又写作“毋论”、“勿论”)在历史发展过程中不断语法化和词汇化的结果。双音化是连词“无论”语法化的动因,句法环境和重新分析是连词“无论”语法化的重要机制。 展开更多
关键词 无论 连词 跨层结构 语法化
下载PDF
A Fairness Resource Allocation Algorithm for Coverage and Capacity Optimization in Wireless Self-Organized Network 被引量:5
2
作者 Pan Zhao Lei Feng +2 位作者 Peng Yu Wenjing Li Xuesong Qiu 《China Communications》 SCIE CSCD 2018年第11期10-24,共15页
To achieve the higher resource efficiency, Coverage and Capacity Optimization(CCO) as an important role of the network self-healing and self-optimization, has become a focus topic in wireless Self-Organized Network(SO... To achieve the higher resource efficiency, Coverage and Capacity Optimization(CCO) as an important role of the network self-healing and self-optimization, has become a focus topic in wireless Self-Organized Network(SON). In this paper, a novel CCO scheme is proposed to maximize utility function of the integrated coverage and capacity. It starts with the analysis on the throughput proportional fairness(PF) algorithm and then proposes the novel Coverage and Capacity Proportional Fairness(CCPF) allocation algorithm along with a proof of the algorithms convergence. This proposed algorithm is applied in a coverage capacity optimization scheme which can guarantee the reasonable network capacity by the coverage range accommodation. Next, we simulate the proposed CCO scheme based on telecom operators' real network data and compare with three typical resource allocation algorithms: round robin(RR), proportional fairness(PF) and max C/I. In comparison of the PF algorithm, the numerical results show that our algorithm increases the average throughput by 1.54 and 1.96 times with constructed theoretical data and derived real network data respectively. 展开更多
关键词 self-organized network coverageand capacity optimization resource allocationalgorithm user fairness.
下载PDF
Leadless pacemakers: a contemporary review 被引量:1
3
作者 Neal Bhatia Mikhael El-Chami 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2018年第4期249-253,共5页
1 Introduction Over one million cardiac pacemakers are implanted every year worldwide,[11 of which approximately 200,000 are implanted in the United States alone.121 Combined with an aging population and increasing p... 1 Introduction Over one million cardiac pacemakers are implanted every year worldwide,[11 of which approximately 200,000 are implanted in the United States alone.121 Combined with an aging population and increasing pacing indications, these numbers are expected to grow. Since the first pacemaker implantation in 1950s, cardiac pacemaker technology has rapidly advanced. Reduction in generator size, increased battery longevity, quality of pacemaker leads, algorithmic and rate responsive programming-all have revolutionized and transformed the implantation and management of transvenous cardiac pacemaker (TV-PPM). 展开更多
关键词 Leadless pacemakers Micra Nanostim PERFORATION
下载PDF
Approximate Symmetries and Infinite Series Symmetry Reduction Solutions to Perturbed Kuramoto-Sivashinsky Equation 被引量:2
4
作者 YAO Ruo-Xia JIAO Xiao-Yu LOU Sen-Yue 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第5期785-788,共4页
Starting from Lie symmetry theory and combining with the approximate symmetry method, and using the package LieSYMGRP proposed by us, we restudy the perturbed Kuramoto-Sivashinsky (KS) equation. The approximate symm... Starting from Lie symmetry theory and combining with the approximate symmetry method, and using the package LieSYMGRP proposed by us, we restudy the perturbed Kuramoto-Sivashinsky (KS) equation. The approximate symmetry reduction and the infinite series symmetry reduction solutions of the perturbed KS equation are constructed. Specially, if selecting the tanh-type travelling wave solution as initial approximate, we not only obtain the general formula of the physical approximate similarity solutions, but also obtain several new explicit solutions of the given equation, which are first reported here. 展开更多
关键词 perturbed Kuramoto-Sivashinsky equation approximate symmetry reduction series reduction solution
下载PDF
Road boundary estimation to improve vehicle detection and tracking in UAV video 被引量:1
5
作者 张立业 彭仲仁 +1 位作者 李立 王华 《Journal of Central South University》 SCIE EI CAS 2014年第12期4732-4741,共10页
Video processing is one challenge in collecting vehicle trajectories from unmanned aerial vehicle(UAV) and road boundary estimation is one way to improve the video processing algorithms. However, current methods do no... Video processing is one challenge in collecting vehicle trajectories from unmanned aerial vehicle(UAV) and road boundary estimation is one way to improve the video processing algorithms. However, current methods do not work well for low volume road, which is not well-marked and with noises such as vehicle tracks. A fusion-based method termed Dempster-Shafer-based road detection(DSRD) is proposed to address this issue. This method detects road boundary by combining multiple information sources using Dempster-Shafer theory(DST). In order to test the performance of the proposed method, two field experiments were conducted, one of which was on a highway partially covered by snow and another was on a dense traffic highway. The results show that DSRD is robust and accurate, whose detection rates are 100% and 99.8% compared with manual detection results. Then, DSRD is adopted to improve UAV video processing algorithm, and the vehicle detection and tracking rate are improved by 2.7% and 5.5%,respectively. Also, the computation time has decreased by 5% and 8.3% for two experiments, respectively. 展开更多
关键词 road boundary detection vehicle detection and tracking airborne video unmanned aerial vehicle Dempster-Shafer theory
下载PDF
Using Extension Theory and Fuzzy Analytic Hierarchy Process on Heterogeneous Wireless Network Selection Algorithm 被引量:1
6
作者 张裕 郑正奇 陈丽娜 《Journal of Donghua University(English Edition)》 EI CAS 2012年第5期417-422,共6页
In order to solve the problem that determining decision factors weights is of subjectivity in heterogeneous wireless network selection algorithm, a network selection algorithm based on extension theory and fuzzy analy... In order to solve the problem that determining decision factors weights is of subjectivity in heterogeneous wireless network selection algorithm, a network selection algorithm based on extension theory and fuzzy analytic hierarchy process (FAHP) is proposed in this paper. In addition, user and operator codetermine the optimal network using the proposed algorithm, which can give consideration to user and operator benefits. The fuzzy judgment matrix is coustructed by membership degree of decision factors which is calculated according to extension theory. The comprehensive weight of each decision factor is obtained using FAHP. Finally, the optimal network is selected through total property value ranldng of each candidate network under user preference and operator preference. The simulation results show that the proposed algorithm can select the optimal network efficiently and accurately, satisfy user preference, and implement load balance between networks. 展开更多
关键词 heterogeneous wireless network optimal network selection extension theory fuzzy analytic hierarchy process (FAHP) load balancing
下载PDF
Dynamic overlapped spectrum allocation based on potential game in cognitive radio networks 被引量:1
7
作者 贾亚男 Yue Dianwu 《High Technology Letters》 EI CAS 2014年第4期401-408,共8页
In order to make full use of wireless spectrum resources,the behavior of cognitive radio(CR)for dynamic spectrum allocation is analyzed based on the game theoretic framework.The traditional spectrum allocation schemes... In order to make full use of wireless spectrum resources,the behavior of cognitive radio(CR)for dynamic spectrum allocation is analyzed based on the game theoretic framework.The traditional spectrum allocation schemes consider the spectrum allocation among independent frequency bands only,without taking into account mutually overlapped frequency bands.For this reason,an optimal allocation etiquette is defined to promote the cross characteristic of the frequency bands in a dynamic spectrum allocation model.New interference operator and interference temperature constraints are introduced in order to realize calculation of the interference,and the corresponding spectrum allocation scenario can be further formulated as a potential game.Based on the characteristic of dynamic selection using the game theory and the interference avoidance rule of interference temperature,the robustness of CR networks is increased and the scenario is more suitable for the dynamic changing of actual wireless communication and energy saving communication systems.Simulation results show that the signal to interference and noise ratio(SINR) level can be significantly improved through the optimal allocation of any available spectrum.The utilization rate of spectrum and throughput of overall CR networks are increased by fully utilizing the spectrum resources in the dynamic spectrum allocation model. 展开更多
关键词 cognitive radio (CR) game theory spectrum allocation nash equilibrium
下载PDF
Passive control of a 4-scroll chaotic system 被引量:1
8
作者 王发强 刘崇新 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第4期946-950,共5页
This paper studies the control of a new chaotic system which can generate 4-scroll attractors. Based on the properties of a passive system, it derives the essential conditions under which this new chaotic system could... This paper studies the control of a new chaotic system which can generate 4-scroll attractors. Based on the properties of a passive system, it derives the essential conditions under which this new chaotic system could be equivalent to a passive system and globally asymptotically stabilize at a zero equilibrium point via smooth state feedback. Simulation results and circuit experiment show that the proposed chaos control method is effective. 展开更多
关键词 a 4-scroll chaotic system passive network theory asymptotically stabilized
下载PDF
A DATA MINING METHOD BASED ON CONSTRUCTIVE NEURAL NETWORKS 被引量:4
9
作者 Wang Lunwen Zhang Ling 《Journal of Electronics(China)》 2007年第1期133-137,共5页
In this letter,Constructive Neural Networks (CNN) is used in large-scale data mining. By introducing the principle and characteristics of CNN and pointing out its deficiencies,fuzzy theory is adopted to improve the co... In this letter,Constructive Neural Networks (CNN) is used in large-scale data mining. By introducing the principle and characteristics of CNN and pointing out its deficiencies,fuzzy theory is adopted to improve the covering algorithms. The threshold of covering algorithms is redefined. "Extended area" for test samples is built. The inference of the outlier is eliminated. Furthermore,"Sphere Neighborhood (SN)" are constructed. The membership functions of test samples are given and all of the test samples are determined accordingly. The method is used to mine large wireless monitor data (about 3×107 data points),and knowledge is found effectively. 展开更多
关键词 Data mining Neural networks Constructive Neural Networks (CNN) Wireless monitoring
下载PDF
Cause Analysis of Consumer‑Grade UAV Accidents Based on Grounded Theory‑Bayesian Network 被引量:2
10
作者 YUE Rentian HAN Meng HOU Bowen 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2022年第5期584-592,共9页
In order to reduce the accident rate of consumer-grade unmanned aerial vehicles(UAVs)in daily use scenarios,the accident causes are analyzed based on the accident cases of consumer-grade UAVs.By extracting accident ca... In order to reduce the accident rate of consumer-grade unmanned aerial vehicles(UAVs)in daily use scenarios,the accident causes are analyzed based on the accident cases of consumer-grade UAVs.By extracting accident causing factors based on the Grounded theory,the relationship between these factors is analyzed.The Bayesian network for consumer-grade UAV accidents is constructed.With the Grounded theory-Bayesian network,the probability of four types of accidents is inferred:fall,air collision,disappearance,and personal injury.With the posterior probability of each factor being reversely reasoned,the causal chain with the maximum probability of each accident is obtained.After the sensitivity of each factor is analyzed,the key nodes in the network accordingly are inferred.Then the causing factors of consumer-grade UAV accidents are analyzed.The results show that the probability of fall accident is the highest,the fall accident is associated with the probabilistic maximum causal chain of personal injury,and the sensitivity analysis results of each type of accident as the result node are inconsistent. 展开更多
关键词 consumer-grade UAV Grounded theory Bayesian network key nodes accident causes
下载PDF
Study on Surface Properties for Non-polar Fluids with Density Functional Theory
11
作者 吴畏 陆九芳 +2 位作者 付东 刘金晨 李以圭 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2004年第2期256-262,共7页
The density functional theory, simplified by the local density approximation and mean-field approxi-mation, is applied to study the surface properties of pure non-polar fluids. A reasonable long rang correction is ado... The density functional theory, simplified by the local density approximation and mean-field approxi-mation, is applied to study the surface properties of pure non-polar fluids. A reasonable long rang correction is adopted to avoid the truncation of the potential. The perturbation theory is applied to establish the equation for the phase equilibrium, in which the hard-core chain fluid is as the reference fluid and the Yukawa potential is used as the perturbation term. Three parameters, ε/κ, d and ms, are regressed frorn the vapor-liquid equilibria, and the surface properties, including density profile, surface tension and local surface tension profile are predicted with these parameters. 展开更多
关键词 density functional theory surface tension density profile pure non-polar fluids
下载PDF
AN EFFICIENT GPU ACCELERATION FORMAT FOR FINITE ELEMENT ANALYSIS
12
作者 Tian Jin Li Gong +1 位作者 Fei Wu Zeng Guohui 《Journal of Electronics(China)》 2013年第6期599-608,共10页
This paper proposes a new Graphics Processing Unit(GPU)-accelerated storage format to speed up Sparse Matrix Vector Products(SMVPs) for Finite Element Method(FEM) analysis of electromagnetic problems.A new format call... This paper proposes a new Graphics Processing Unit(GPU)-accelerated storage format to speed up Sparse Matrix Vector Products(SMVPs) for Finite Element Method(FEM) analysis of electromagnetic problems.A new format called Modified Compile Time Optimization(MCTO) format is used to reduce much execution time and design for hastening the iterative solution of FEM equations especially when rows have uneven lengths.The MCTO-applied FEM is about 10 times faster than conventional FEM on a CPU,and faster than other row-major ordering formats on a GPU.Numerical results show that the proposed GPU-accelerated storage format turns out to be an excellent accelerator. 展开更多
关键词 Finite Element Method (FEM) Graphics Processing Unit (GPU) Parallelizationstrategy Modified Compile Time Optimization (MCTO)
下载PDF
Invited Paper: Antenna Selection in Energy Efficient MIMO Systems: A Survey 被引量:7
13
作者 Zhou Xingyu Bai Bo Chen Wei 《China Communications》 SCIE CSCD 2015年第9期162-173,共12页
With the explosive growth and need for high-speed wireless communications, more and more energy is consumed to support the required quality of service. Therefore, energy efficient or green communication has become a v... With the explosive growth and need for high-speed wireless communications, more and more energy is consumed to support the required quality of service. Therefore, energy efficient or green communication has become a very hot topic under the ground of limited energy resource and environmentally friendly transmission schemes. MIMO technique is capable of reducing the transmission power thanks to its diversity and multiplexing gain. Moreover, antenna selection(AS) is an alternative to extract many of the benefits in MIMO systems with a reduced cost of complexity and power. Although many works including several survey papers have investigated AS in MIMO systems, the goal of these works is only the capacity maximization or error rate minimization, which fails to guarantee the optimality of the energy efficiency in MIMO systems. In this paper, we overview the state of the art in the AS schemes in energy efficient MIMO systems, the goal of which is to optimize the energy efficiency of the whole system. Specifically, we introduce energy efficient AS in point-to-point MIMO, cooperative MIMO, multiuser MIMO and largescale MIMO systems, respectively. Several challenging and practical issues in this area are also addressed. 展开更多
关键词 antenna selection energy efficient holistic power model MIMO
下载PDF
Accounting Aspects on Biotechnology and Their Products: According to Theory and Practice in Bulgaria
14
作者 Rumiana Pozharevska 《Chinese Business Review》 2015年第3期137-142,共6页
Biotechnology and the rights on biotechnological products are present-day topics, but at the same time, topics with deep historical roots. Biotechnological achievements are not a novelty to Bulgaria. They have existed... Biotechnology and the rights on biotechnological products are present-day topics, but at the same time, topics with deep historical roots. Biotechnological achievements are not a novelty to Bulgaria. They have existed for thousands of years and are connected with the production of milk and milk products, rose oil, herbal raw materials, and etc.. Contemporary biotechnological achievements are marketed in the form of nutritional, medicinal, and chemical products or as environmental protection. Traditional knowledge and achievements of modern science put the legal protection of biotechnology and its products on the agenda. In the national context, such rights have been statutory regulated and studied by specialists in the field of intellectual property. The problematic issues have not been so adequately treated in the country in terms of accounting theory and practice. The rights on biotechnology and biotechnological products are not within the scope of accounting items and accounting assets respectively. This is the motivation for the author to study the rights on biotechnology products within the context of their recognition as intangible assets. The author tries to present the conceptual framework for their identification and recognition as accounting items, as well as to define some scientific application problems on the topic. 展开更多
关键词 intangible assets new items of intellectual property rights on biotechnology products ACCOUNTING
下载PDF
Theoretical Design of Energy Harvesting Module or Wireless Power Transmission Receiver Using Magnetic Field of 0.2 mT at 60 Hz 被引量:1
15
作者 Kunihisa Tashiro Hiroyuki Wakiwaka Yu Uchiyama 《Journal of Energy and Power Engineering》 2013年第4期740-745,共6页
This paper presents a theoretical design method for a magnetic energy harvesting module. This module consists of an air-core coil and resonant capacitor. With a simple RLC circuit model, it can derive an equation of h... This paper presents a theoretical design method for a magnetic energy harvesting module. This module consists of an air-core coil and resonant capacitor. With a simple RLC circuit model, it can derive an equation of harvesting energy as a function of coil size. In order to demonstrate the magnetic field, a uniform magnetic field is generated by the developed coil system. From the experimented results, it is successfully demonstrated 100 mW of energy harvesting from a magnetic field of 0.09 mT at 60 Hz. This value is in good agreement with the estimated results. Harvested energy is proportional to the square of the magnetic flux density. However, ICNIRP2010 provides a guideline that an acceptable level for human health in a public space is 0.2 mT at power-line frequency. This paper also discuss the possibilities of several applications related with both magnetic energy harvesting and wireless power transmission. 展开更多
关键词 Magnetic energy harvesting wireless power transmission theoretical design ICNIRP2010.
下载PDF
A novel digital control strategy of three-phase shunt active power filter under non-ideal mains voltages 被引量:1
16
作者 胡志坤 陈志文 +2 位作者 华长春 王会海 丁家峰 《Journal of Central South University》 SCIE EI CAS 2011年第6期2021-2030,共10页
A novel control strategy for three-phase shunt active power filter (SAPF) was proposed to improve its performance under non-ideal mains voltages. The approach was inspired by our finding that the classic instantaneous... A novel control strategy for three-phase shunt active power filter (SAPF) was proposed to improve its performance under non-ideal mains voltages. The approach was inspired by our finding that the classic instantaneous reactive power theory based algorithm was unsatisfactory in terms of isolating positive sequence fundamental active components exactly under non-ideal mains voltages. So, a modified ip-iq reference current calculation method was presented. With usage of the new method, not only the positive sequence but also the fundamental active current components can be accurately isolated from load current. A deadbeat closed-loop control model is built in order to eliminate both delay error and tracking error between reference voltages and compensation voltages under unbalanced and distorted mains voltages. Computer simulation results show that the proposed strategy is effective with better tracking ability and lower total harmonic distortion (THD). The strategy is also applied to a 10 kV substation with a local electrolysis manganese plant injecting a large amount of harmonics into the power system, and is proved to be more practical and efficient. 展开更多
关键词 non-ideal mains voltage deadbeat control fundamental positive sequence active current shunt active power filter
下载PDF
Design of ADS-B Simulator
17
作者 Hyeon-Cheol Lee Sang Gyu Lee Sang Soon Yong 《Journal of Electrical Engineering》 2018年第4期216-220,共5页
In this paper, the ADS-B (automatic dependent surveillance-broadcast) used for manned aircrafts is chosen for aSee-and-Avoid sensor of UAV (unmanned aerial vehicle), then GDL90 type is selected among three type... In this paper, the ADS-B (automatic dependent surveillance-broadcast) used for manned aircrafts is chosen for aSee-and-Avoid sensor of UAV (unmanned aerial vehicle), then GDL90 type is selected among three types of ADS-B. The serialcommunication data protocol which communicates between GDL90 and control panel of GDL90 is analyzed and tailored for theinterface of the GDL90 simulator here. This ADS-B (GDL90) simulator sends intruder information to FCC (flight control computer)of UAV for collision avoidance function. 展开更多
关键词 ADS-B GDL90 1090ES UAV collision-avoidance.
下载PDF
GRAPH-THEORETIC ALGORITHM FOR SPECTRUM ALLOCATION IN IEEE 802.22 WIRELESS MESH NETWORK
18
作者 He Tao Wang Suoping Zhang Min 《Journal of Electronics(China)》 2010年第4期433-439,共7页
The IEEE 802.22 standard based on wireless Cognitive Radio (CR) is an optimal solution to resolve the inefficient spectrum utility problem. In this paper, we focus on the spectrum allocation in IEEE 802.22 mesh networ... The IEEE 802.22 standard based on wireless Cognitive Radio (CR) is an optimal solution to resolve the inefficient spectrum utility problem. In this paper, we focus on the spectrum allocation in IEEE 802.22 mesh networks and propose a new graph-theory algorithm. The algorithm aims at two objectives: one is the sum of the allocated channel bandwidth is maximum, and the other is the number of users can be active simultaneity is maximum. In this proposed algorithm, the topology of network was modeled as a general graph and could be transformed into a weighted complete bipartite-graph by three processes. The simulations show that the presented algorithm can improve the performance of spectrum allocation. 展开更多
关键词 Cognitive Radio (CR) Wireless Regional Area Network (WRAN) Spectrum allocation
下载PDF
Approach for Local Multi-Domain Cognition in Cognitive Network
19
作者 张文柱 弋渤海 《China Communications》 SCIE CSCD 2013年第1期146-156,共11页
During the evolution from cognitive radio to cognitive networks,the environment cognition extended from wireless environments to network and user environments.To understand the basic theory of Local Multi-Domain Cogni... During the evolution from cognitive radio to cognitive networks,the environment cognition extended from wireless environments to network and user environments.To understand the basic theory of Local Multi-Domain Cognition(LMDC),and to provide a theoretical basis for further study in cooperative multi-domain cognition and initiative multi-domain cognition,the LMDC is investigated in this paper.A Local Single-Domain Cognitive(LSDC)approach is first proposed based on multidimensional edge detection theory.This approach can divide the parameter space that describes the single-domain environment into different areas,and can represent each area with an identifier.Using this as a foundation,the single-domain environment is extended to multi-domain environments,and an LMDC approach is presented to describe the LMDC environment.The paper concludes by introducing two examples and the corresponding analysis to illustrate the feasibility of the proposed LMDC approach. 展开更多
关键词 cognitive radio cognitive networks local multi-domain cognition multi-dimensionedge detection LSDC
下载PDF
Non-Cooperative Differential Game Based Load Balancing Algorithm in Radio-Over-Fibre System
20
作者 HE Zhen WANG Jianping 《China Communications》 SCIE CSCD 2014年第A02期79-85,共7页
Load balancing plays a critical role in a cellular network. As one kind of cellular network, Radio-over-Fibre (RoF) system can provide ubiquitous high data-rate transmissions, which has attracted many attentions, bu... Load balancing plays a critical role in a cellular network. As one kind of cellular network, Radio-over-Fibre (RoF) system can provide ubiquitous high data-rate transmissions, which has attracted many attentions, but it also suffer load unbalancing problem. In order to improve the system performance, in this paper, we propose a novel loading balance scheme in RoF system based on differential game theory. The scheme formulates the load allocated to each RAP (Radio Access Point) as a Nasb Equilibrium, using non-cooperative differential game to obtain the optical load allocation of each RAP. The simulations performed show that the non-cooperative differential game algorithm is applicable and the optimal load solution can be achieved. 展开更多
关键词 loading balancing ROF RAP non- cooperative differential game
下载PDF
上一页 1 2 下一页 到第
使用帮助 返回顶部