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User Fairness Scheme with Proportional Fair Scheduling in Multi-user MIMO Limited Feedback System
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作者 Hongyu Wang Weixiao Meng Trungtan Nguyen 《Communications and Network》 2013年第3期113-118,共6页
In Multi-user MIMO (MU-MIMO) downlink system, suitable user selection schemes can improve spatial diversity gain. In most of previous studies, it is always assumed that the base station (BS) knows full channel state i... In Multi-user MIMO (MU-MIMO) downlink system, suitable user selection schemes can improve spatial diversity gain. In most of previous studies, it is always assumed that the base station (BS) knows full channel state information (CSI) of each user, which does not consider the reality. However, there are only limited feedback bits in real system. Besides, user fairness is often ignored in most of current user selection schemes. To discuss the user fairness and limited feedback, in this paper, the user selection scheme with limited feedback bits is proposed. The BS utilizes codebook precoding transmitting strategy with LTE codebook. Furthermore, this paper analyzes the influence of the number of feedback bits and the number of users on user fairness and system sum capacity. Simulation results show that in order to achieve better user fairness, we can use fewer bits for feedback CSI when the number of user is small, and more feedback bits when the number of users is large. 展开更多
关键词 user FAIRNEss sCHEME with Proportional FAIR scheduling in MULTI-user MIMO LIMITED feedback system
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Online composite shape recognition based on relevance feedback
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作者 王强 孙正兴 《Journal of Southeast University(English Edition)》 EI CAS 2005年第2期153-158,共6页
This paper describes a novel method of online composite shape recognition interms of the relevance feedback technology to capture a user's intentions incrementally, and adynamic user modeling method to adapt to va... This paper describes a novel method of online composite shape recognition interms of the relevance feedback technology to capture a user's intentions incrementally, and adynamic user modeling method to adapt to various users' styles. First, the relevance feedback isadapted to refine the recognition results and reduce the ambiguity incrementally based on theestablishment of a feature-based vector model of a user's sketches. Secondly, a dynamic usermodeling is introduced to model the user's sketching habits based on recording and analyzinghistorical information incrementally. A model-based matching strategy is also employed in the methodto recognize sketches dynamically. Experiments prove that the proposed method is both effective andefficient. 展开更多
关键词 sketchy-based user interface online composite shape recognition dynamicuser modeling relevance feedback
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On Teacher's Feedback from the Perspective of Communication
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作者 张芳 《英语广场(学术研究)》 2011年第Z4期115-118,共4页
Classroom interaction involves many aspects,among which teacher's feedback is an important element.This paper aimes at studying teacher's feedback from the perspective of communication.It first discusses the d... Classroom interaction involves many aspects,among which teacher's feedback is an important element.This paper aimes at studying teacher's feedback from the perspective of communication.It first discusses the definition of teacher's feedback and analyses the functions of teacher's feedback in the classroom interaction and then explores some strategies for effective feedback based on communication theory. 展开更多
关键词 teacher’s feedback CLAssROOM interaction VERBAL feedback communication sTRATEGIEs
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Angle-Based Beamforming in mmWave Massive MIMO Systems with Low Feedback Overhead Using Multi-Pattern Codebooks 被引量:1
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作者 Yuyan Zhao Yanan Liu +2 位作者 Gary Boudreau Akram Bin Sediq Xianbin Wang 《China Communications》 SCIE CSCD 2019年第9期18-30,共13页
The integration of millimeter-wave(mmWave)communications and massive multiple input multiple output(MIMO)techniques is a promising solution to dramatically increase the 5G network throughput.By using large antenna arr... The integration of millimeter-wave(mmWave)communications and massive multiple input multiple output(MIMO)techniques is a promising solution to dramatically increase the 5G network throughput.By using large antenna arrays,beamforming can be adopted to improve the 5G capacity by employing spatial domain resources.In a frequency division duplexing(FDD)based 5G mmWave MIMO system,beamforming operation requires timely downlink channel state information(CSI)feedback.However,the rapid channel variations caused by short wavelength of mmWave band,and the high-level feedback information required due to the large number of antennas in massive MIMO system lead to the significantly increased beamforming overhead.In this paper,by exploiting the higher angular stability of such channels,we propose an angle-based beamforming scheme to reduce the feedback frequency and the number of feedback bits.To facilitate this approach users are initially selected to reduce the intra-zone interference before beamforming.Besides,location related feedback,which is not affected by the number of antennas,is adopted to reduce overhead.The simulation results show that two proposed user selection algorithms can adapt to scenarios with diverse requirements,while the feedback overhead of proposed angle-based beamforming algorithm is sharply reduce compared with that of CSIbased beamforming algorithm. 展开更多
关键词 angle-based BEAMFORMING codebook feedback reduction user selection
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Customization Product Design Based on User's Emotion and Needs 被引量:3
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作者 金纯 张春林 刘文枝 《Defence Technology(防务技术)》 SCIE EI CAS 2005年第2期245-249,共5页
The paper presents a design method that ensures the ingenuity of the product form as well as the whole and exact expression of user’s needs. The key idea is to establish an automatic design system which can transform... The paper presents a design method that ensures the ingenuity of the product form as well as the whole and exact expression of user’s needs. The key idea is to establish an automatic design system which can transform the user’s language needs into the product features in real-time. A rifle was taken as a research instance and soldiers were chosen as evaluation customers. The theory of fuzzy set and semantic difference are adopted to evaluate the relationship between user’s needs and product features as well as their alternatives. FAHP (fuzzy analytic hierarchy process) is utilized to judge the user’s satisfactory forms. This method can also be applied to other product form designs. 展开更多
关键词 users needs product form CUsTOMIZATION fuzzy number
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Use of methotrexate in inflammatory bowel disease in 2014: A User's Guide 被引量:4
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作者 Arun Swaminath Raja Taunk Garrett Lawlor 《World Journal of Gastrointestinal Pharmacology and Therapeutics》 CAS 2014年第3期113-121,共9页
Methotrexate has been used an immunomodulator in many autoimmune diseases,including inflammatory bowel disease. However,many physicians are unfamiliar or uncomfortable with its use in the management of inflammatory bo... Methotrexate has been used an immunomodulator in many autoimmune diseases,including inflammatory bowel disease. However,many physicians are unfamiliar or uncomfortable with its use in the management of inflammatory bowel disease. We summarize the data for use of methotrexate in common clinical scenarios:(1) steroid dependant Crohn's disease(CD);(2) maintenance of remission in steroid free CD;(3) azathioprine failures in CD;(4) in combination therapy with Anti-TNF agents in CD;(5) decreasing antibody formation to Anti-TNF therapy in CD;(6) management of fistulizing disease in CD; and(7) as well as induction and maintenance of remission in ulcerative colitis. An easy to use algorithm is provided for the busy clinician to access and safely prescribe methotrexate for their inflammatory bowel disease patients. 展开更多
关键词 METHOTREXATE Inflammatory BOWEL DIsEAsE Crohn’s DIsEAsE ULCERATIVE colitis IMMUNOMODULATORs METHOTREXATE users GUIDE
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Information perception and feedback mechanism and key techniques of multi-modality human-robot interaction for service robots 被引量:1
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作者 赵其杰 《Journal of Shanghai University(English Edition)》 CAS 2006年第3期281-281,共1页
With the increasing of the elderly population and the growing hearth care cost, the role of service robots in aiding the disabled and the elderly is becoming important. Many researchers in the world have paid much att... With the increasing of the elderly population and the growing hearth care cost, the role of service robots in aiding the disabled and the elderly is becoming important. Many researchers in the world have paid much attention to heaRthcare robots and rehabilitation robots. To get natural and harmonious communication between the user and a service robot, the information perception/feedback ability, and interaction ability for service robots become more important in many key issues. 展开更多
关键词 service robot MULTI-MODALITY human-robot interaction user model interaction protocol information perception and feedback.
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Static Output Feedback Control for Discrete-time Piecewise Linear Systems: an LMI Approach 被引量:7
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作者 DING Da-Wei YANG Guang-Hong 《自动化学报》 EI CSCD 北大核心 2009年第4期337-344,共8页
关键词 Piecewise linear systems piecewise quadratic Lyapunov function Finsler's lemma static output feedback sOF) linear matrix inequality (LMI)
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Analysis and Simulations of Open-Source Intelligence Process System Dynamics from User’s Perspective 被引量:1
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作者 Huan Liu Zhenyu Tang +1 位作者 Ning Zhao Wei Qian 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第1期541-558,共18页
In today’s society with advanced Internet,the amount of information increases dramatically with each passing day,which leads to increasingly complex processes of open-source intelligence.Therefore,it is more importan... In today’s society with advanced Internet,the amount of information increases dramatically with each passing day,which leads to increasingly complex processes of open-source intelligence.Therefore,it is more important to rationalize the operation mode and improve the operation efficiency of open-source intelligence under the premise of satisfying users’needs.This paper focuses on the simulation study of the process system of opensource intelligence from the user’s perspective.First,the basic concept and development status of open-source intelligence are introduced in details.Second,six existing intelligence operation process models are summarized and their advantages and disadvantages are compared in focus.Based on users’preference,the open-source intelligence system simulation theory model is constructed from four aspects:intelligence collection,intelligence processing,intelligence analysis,and intelligence delivery.Meanwhile,the dynamics model of the open-source intelligence process system is constructed based on the open-source intelligence system simulation theoretical model,which specifically includes five parts:determination of system boundary,construction of causal loop diagram,construction of stock flow diagram,writing ofmathematical equations,and system sensitivity test.Finally,the system simulation results were analyzed.It was found that improving the system of intelligence agencies,opening up government affairs,improving the professional level of intelligence personnel,strengthening the communication and cooperation among personnel of various intelligence departments,and expressing intelligence products through diverse forms can effectively improve the operational efficiency of the open-source intelligence process system. 展开更多
关键词 Open-source intelligence system dynamics feedback user demand deviation
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Frequent Itemset Mining of User’s Multi-Attribute under Local Differential Privacy 被引量:2
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作者 Haijiang Liu Lianwei Cui +1 位作者 Xuebin Ma Celimuge Wu 《Computers, Materials & Continua》 SCIE EI 2020年第10期369-385,共17页
Frequent itemset mining is an essential problem in data mining and plays a key role in many data mining applications.However,users’personal privacy will be leaked in the mining process.In recent years,application of ... Frequent itemset mining is an essential problem in data mining and plays a key role in many data mining applications.However,users’personal privacy will be leaked in the mining process.In recent years,application of local differential privacy protection models to mine frequent itemsets is a relatively reliable and secure protection method.Local differential privacy means that users first perturb the original data and then send these data to the aggregator,preventing the aggregator from revealing the user’s private information.We propose a novel framework that implements frequent itemset mining under local differential privacy and is applicable to user’s multi-attribute.The main technique has bitmap encoding for converting the user’s original data into a binary string.It also includes how to choose the best perturbation algorithm for varying user attributes,and uses the frequent pattern tree(FP-tree)algorithm to mine frequent itemsets.Finally,we incorporate the threshold random response(TRR)algorithm in the framework and compare it with the existing algorithms,and demonstrate that the TRR algorithm has higher accuracy for mining frequent itemsets. 展开更多
关键词 Local differential privacy frequent itemset mining users multi-attribute
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An Intelligent IEQ Monitoring and Feedback System:Development and Applications 被引量:1
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作者 Yang Geng Zhongchen Zhang +4 位作者 Juan Yu Hongzhong Chen Hao Zhou Borong Lin Weimin Zhuang 《Engineering》 SCIE EI CAS 2022年第11期218-231,共14页
Indoor environmental quality(IEQ)significantly affects human health and wellbeing.Therefore,continuous IEQ monitoring and feedback is of great concern in both the industrial and academic communities.However,most exist... Indoor environmental quality(IEQ)significantly affects human health and wellbeing.Therefore,continuous IEQ monitoring and feedback is of great concern in both the industrial and academic communities.However,most existing studies only focus on developing sensors that cost-effectively promote IEQ measurement while ignoring interactions between the human side and IEQ monitoring.In this study,an intelligent IEQ monitoring and feedback system-the Intelligent Built Enviroment(IBEM)-is developed.Firstly,the IBEM hardware instrument integrates air temperature,relative humidity,CO_(2),particulate matter with an aerodynamic diameter no greater than _(2.5)μm(PM_(2.5)),and illuminance sensors within a small device.The accuracy of this integrated device was tested through a co-location experiment with reference sensors;the device exhibited a strong correlation with the reference sensors,with a slight deviation(R^(2)>0.97 and slopes between 1.01 and 1.05).Secondly,a wireless data transmission module,a cloud storage module,and graphical user interfaces(i.e.,a web platform and mobile interface)were built to establish a pathway for dataflow and interactive feedback with the occupants of the indoor environments.Thus,the IEQ parameters can be continuously monitored with a high spatiotemporal resolution,interactive feedback can be induced,and synchronous data collection on occupant satisfaction and objective environmental parameters can be realized.IBEM has been widely applied in 131 buildings in 18cities/areas in China,with 1188 sample locations.Among these applications,we report on the targeted IEQ diagnoses of two individual buildings and the exploration of relationships between subjective and objective IEQ data in detail here.This work demonstrates the great value of IBEM in both industrial and academic research. 展开更多
关键词 Indoor environmental quality(IEQ) sENsORs Continuous monitoring Graphical user interface Interactive feedback
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On the Permanence of a Nonautonomous Nicholson’s Blowflies Model with Feedback Control and Delay 被引量:2
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作者 赖尾英 《Chinese Quarterly Journal of Mathematics》 CSCD 2011年第4期568-572,共5页
A nonautonomous Nicholson's Blowflies model with feedback control and delay is investigated in this paper. We show that for this system, feedback control variable has no influence on the persistent property of the... A nonautonomous Nicholson's Blowflies model with feedback control and delay is investigated in this paper. We show that for this system, feedback control variable has no influence on the persistent property of the system. 展开更多
关键词 feedback control PERMANENCE Nicholson’s Blowflies model
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Exponential Synchronization of Master-Slave Lur'e Systems via Intermittent Time-Delay Feedback Control 被引量:1
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作者 王一晶 郝建娜 左志强 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第10期679-686,共8页
This paper concerns with the master-slave exponential synchronization analysis for a class of general Lur'esystems with time delay.Different from the previous methods based on the differential inequality technique... This paper concerns with the master-slave exponential synchronization analysis for a class of general Lur'esystems with time delay.Different from the previous methods based on the differential inequality technique, a newapproach is proposed to derive some new exponential synchronization criteria.The restriction that the control widthhas to be larger than the time delay is removed.This leads to a larger application scope for our method.Moreover, notranscendental equation is involved in the obtained result, which reduces the computational burden.Two examples aregiven to validate the theoretical results. 展开更多
关键词 exponential synchronization intermittent control delayed feedback control Razumikhin stabilitytheory Chua's circuits
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User’s Relevance of PIR System Based on Cloud Models 被引量:1
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作者 康海燕 樊孝忠 《Journal of Beijing Institute of Technology》 EI CAS 2006年第2期181-185,共5页
A new method to evaluate fuzzily user's relevance on the basis of cloud models has been proposed. All factors of personalized information retrieval system are taken into account in this method. So using this method f... A new method to evaluate fuzzily user's relevance on the basis of cloud models has been proposed. All factors of personalized information retrieval system are taken into account in this method. So using this method for personalized information retrieval (PIR) system can efficiently judge multi-value relevance, such as quite relevant, comparatively relevant, commonly relevant, basically relevant and completely non-relevant, and realize a kind of transform of qualitative concepts and quantity and improve accuracy of relevance judgements in PIR system. Experimental data showed that the method is practical and valid. Evaluation results are more accurate and approach to the fact better. 展开更多
关键词 personalized information retrieval (PIR) cloud model user's relevance fuzzy evaluation
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Joint Source and Relay Precoding/Beamforming Algorithm for OFDM Multi-user Cooperative Relay Systems 被引量:1
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作者 ZHOU Dong-yue HU Bin-jie 《Journal of Donghua University(English Edition)》 EI CAS 2014年第5期723-726,共4页
In order to reduce the feedback load of multi-user orthogonal frequency division multiplexing ( OFDM ) -based wireless systems, a practiral limited bits feedback precoding algorithm is proposed with direct source-de... In order to reduce the feedback load of multi-user orthogonal frequency division multiplexing ( OFDM ) -based wireless systems, a practiral limited bits feedback precoding algorithm is proposed with direct source-destination link based on amplify-and- forward cooperative relay network under frequency selective fading channels. Using joint minimum mean square error(MMSE) filter, the receiving decoding matrix is designed for each user in the paper. Source precoding (beamforming) matrix is optimized with convex function of weight mean square error (MSE). Relay precoding matrix is obtained under MSE decomposition and convex optimization. The precoding matrix index is fed back for clustered subcarrier of OFDM with limited feedback. Then using interpolation algorithm, all precoding matrices are achieved at base station (BS) and relay nodes. Simulations indicate the effectiveness of the proposed limited feedback joint precoding and beam_formlng design. The proposed method can improve bit error rate (BER) performance and obtain better sum-rate performance in contrast to existing algorithms. It displays the BER performance is close to that of the unquantified precoding feedback method. 展开更多
关键词 RELAY MULTI-user PRECODING mean square error (MsE) feedback BITs dual HOP
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LMI-based output feedback fuzzy control of chaotic system with uncertainties 被引量:1
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作者 谭文 王耀南 +1 位作者 段峰 李晓辉 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第11期2529-2534,共6页
This paper studies the robust fuzzy control for nonlinear chaotic system in the presence of parametric uncertainties. An uncertain Takagi-Sugeno (T-S) fuzzy model is employed for fuzzy modelling of an unknown chaoti... This paper studies the robust fuzzy control for nonlinear chaotic system in the presence of parametric uncertainties. An uncertain Takagi-Sugeno (T-S) fuzzy model is employed for fuzzy modelling of an unknown chaotic system. A sufficient condition formulated in terms of linear matrix inequality (LMI) for the existence of fuzzy controller is obtained. Then the output feedback fuzzy-model-based regulator derived from the LMI solutions can guarantee the stability of the closed-loop overall fuzzy system. The T-S fuzzy model of the chaotic Chen system is developed as an example for illustration. The effectiveness of the proposed controller design methodology is finally demonstrated through computer simulations on the uncertain Chen chaotic system. 展开更多
关键词 CHAOs output-feedback controller T-s fuzzy model linear matrix inequality
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A Dynamic Bandwidth Allocation Solution Based on User Behavior and Software Defined EPS
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作者 Bo Zhu Hao Jiang +2 位作者 Lihua Wu Shuwen Yi Hai Wang 《China Communications》 SCIE CSCD 2016年第9期80-90,共11页
For telecommunication operators, how to improve the utilization of bandwidth resources is always a problem which worthy of study, nowadays, this issue has become more and more important, since the traffic load burstin... For telecommunication operators, how to improve the utilization of bandwidth resources is always a problem which worthy of study, nowadays, this issue has become more and more important, since the traffic load bursting in the mobile Internet. So the key to solving this problem is that we need to find a kind of traffic model to predict the traffic load that users need. According to the predicted traffic load to allocate bandwidth to each base station dynamically.But the traffic consumption behavior of a single base station is random, it is difficult to predict[ 1 ]. For this reason, we based on reality that, when the user moves, it may get traffic load from different base stations, therefore, there will have some kind of relationship between those base stations.We use this relationship to establish a kind of Spatial Collaborative Network.consequently, we make use of stability algorithm to divided those base station cluster into different communities, According to the traffic load usage rules which these communities indicated to us, we get a traffic model.At the same time, we studied bow to use this traffic model in the future networks to dynamically allocate bandwidth resources, then we propose a new kind of EPS architecture based on SDN, on this platform, we can deploy our strategy through it's programmable interface.Finally, we designed an experiment to test the performance of our dynamic strategy, and the result shows that our method enables bandwidth utilization has been greatly improved. 展开更多
关键词 bandwidth utilization user's behaviour traffic module sDN
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User space transformation in deep learning based recommendation
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作者 WU Caihua MA Jianchao +1 位作者 ZHANG Xiuwei XIE Dang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2020年第4期674-684,共11页
Deep learning based recommendation methods, such as the recurrent neural network based recommendation method(RNNRec) and the gated recurrent unit(GRU) based recommendation method(GRURec), are proposed to solve the pro... Deep learning based recommendation methods, such as the recurrent neural network based recommendation method(RNNRec) and the gated recurrent unit(GRU) based recommendation method(GRURec), are proposed to solve the problem of time heterogeneous feedback recommendation. These methods out-perform several state-of-the-art methods. However, in RNNRec and GRURec, action vectors and item vectors are shared among users. The different meanings of the same action for different users are not considered. Similarly, different user preference for the same item is also ignored. To address this problem, the models of RNNRec and GRURec are modified in this paper. In the proposed methods, action vectors and item vectors are transformed into the user space for each user firstly, and then the transformed vectors are fed into the original neural networks of RNNRec and GRURec. The transformed action vectors and item vectors represent the user specified meaning of actions and the preference for items, which makes the proposed method obtain more accurate recommendation results. The experimental results on two real-life datasets indicate that the proposed method outperforms RNNRec and GRURec as well as other state-of-the-art approaches in most cases. 展开更多
关键词 recommender system collaborative filtering time heterogeneous feedback recurrent neural network gated recurrent unit(GRU) user space transformation
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Permanence of a Nicholson's Blowflies Model with Feedback Control and Multiple Time-varying Delays
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作者 陈晓英 施春玲 《Chinese Quarterly Journal of Mathematics》 2015年第1期153-158,共6页
This paper covers the dynamic behaviors for a class of Nicholson’s blowflies model with multiple time-varying delay and feedback control. By using the dierential inequality theory, a set of sucient conditions are obt... This paper covers the dynamic behaviors for a class of Nicholson’s blowflies model with multiple time-varying delay and feedback control. By using the dierential inequality theory, a set of sucient conditions are obtained to ensure the permanence of the system. Our result shows that feedback control variables have no influence on the permanence of the system. 展开更多
关键词 PERMANENCE Nicholson’s blowflies model DELAY feedback control
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Fabrication of 32 Gb/s Electroabsorption Modulated Distributed Feedback Lasers by Selective Area Growth Technology
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作者 周代兵 王会涛 +8 位作者 张瑞康 王宝军 边静 安欣 陆丹 赵玲娟 朱洪亮 吉晨 王圩 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第5期66-68,共3页
A 32 Gb/s monolithically integrated electroabsorption modulated laser is fabricated by selective area growth technology. The threshold current of the device is below 13mA. The output power exceeds 10mW at 0V bias when... A 32 Gb/s monolithically integrated electroabsorption modulated laser is fabricated by selective area growth technology. The threshold current of the device is below 13mA. The output power exceeds 10mW at 0V bias when the injection current of the distributed feedback laser is 100mA at 25℃. The side mode suppression ratio is over 50 dB. A 32Gb/s eye diagram is measured with a 3.SVpp nonreturn-to-zero pseudorandom modulation signal at -2.3 V bias. A clearly opening eyediagram with a dynamic extinction ratio of 8.01 dB is obtained. 展开更多
关键词 Fabrication of 32 Gb/s Electroabsorption Modulated Distributed feedback Lasers by selective Area Growth Technology EML EAM DFB InGaAs sAG
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