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Two novel iterative algorithms for interference alignment with symbol extensions in the MIMO interference channel

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Science China(Information Sciences) 2014年第4期57卷 142-155页

作者： WANG Chao deng ke School of Electronic and Information Engineering Xi’an Jiaotong University

Interference alignment(IA)with symbol extensions in the quasi-static flat-fading K-user multipleinput multiple-output(MIMO)interference channel(IC)is considered in this *** general,long symbol extensions are required to achieve the optimal fractional degrees of freedom(DOF).However,long symbol extensions over orthogonal dimensions produce structured(diagonal or block diagonal)channel matrices from transmitters to *** of existing approaches are limited in cases where the channels have some special structures,because they align the interference without preserving the dimensionality of the desired signal *** overcome this common drawback of most existing IA algorithms,two novel iterative algorithms for IA with symbol extensions are *** first algorithm designs transceivers for IA based on the mean square error(MSE)criterion which minimizes the total MSE of the system while preserving the dimensionality of the desired *** novel IA algorithm is a constrained optimization problem which can be solved by Lagrangian *** convergence is proven as *** the reciprocity of alignment,the second algorithm is proposed based on the maximization of the multidimensional case of the generalized Rayleigh *** maximizes each receiver’s signal to interference plus noise ratio(SINR)while preserving the dimensionality of the desired *** simulation results,we show the superiority of the proposed algorithms in terms of four aspects,i.e.,average sum rate,the fraction of the interfering signal power in the desired signal subspace,bit error rate(BER)and the relative power of the weakest desired data stream.

关键词： interference alignment symbol extensions MIMO interference channel iterative algorithm MSE

Resolving conflicts between negotiation success and sensitive information protection in automated trust negotiation

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Frontiers of Computer Science 2011年第2期5卷 135-147页

作者： Bailing LIU Feng XIAO ke deng Department of Information and Management Huazhong Normal University Wuhan 430079 China Huawei Technologies Co. Ltd Wuhan 430000 China The No.92373 of PLA Dalian 116001 China

Automated trust negotiation （ATN） is an approach to establishing mutual trust between strangers wishing to share resources or conduct business by gradually requesting and disclosing digitally signed credentials. In ATN, there are conflicts between negotiation success and sensitive information protection, that is, these two needs cannot be given priority at the same time, which is a challenging problem to resolve. In this paper, a language independent ATN framework, which is dynamic, flexible and adaptive, is presented to address this problem, ensuring negotiation success without sensitive information leakage. This framework is independent of the policy language which is used. However, the language used should have the capability to specify all kinds of sensitive information appearing in credentials and policies, and support the separation of attribute disclosure from credential disclosure. Thus definitions of new language features, which can be incorporated into existing policy languages, are given, enabling the used language to support the capabilities mentioned above.

关键词： automated trust negotiation (ATN) negotiation success sensitive information protection framework policy language

Call Characteristic Network Reveal Geographical Patterns of Call Similarity:Applying Network Analysis to Frog’s Call Research

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Asian Herpetological Research 2021年第1期12卷 110-116页

作者： ke deng Yue YANG Jianguo CUI CAS key Laboratory of Mountain Ecological Restoration and Bioresource Utilization&Ecological Restoration and Biodiversity Conservation key Laboratory of Sichuan Prcnnnce Chengdu Institute of BiologyChinese Academy of SciencesChengdu 610041SichuanChina

Individual’s phenotypic traits are the results of adaptation to ecological ***,different selection pressures caused by heterogeneous environments may result in phenotypic difference,especially for individuals in different geographical ***,we illustrated for the first time to use social network analysis(SNA)for examining whether geographical proximity predicts the similarity patterns in call characteristics among populations of an anuran *** recorded calls from 150 male dorsal-striped opposite-fingered treefrogs(Chiromantis doriae)at 11 populations in Hainan Province and one population in Guangdong Province in China's Mainland,and we measured eight acoustic variables for each *** test didn’t show a correlation between geographical proximity and the similarity in call characteristics among *** addition,we failed to find correlations between a population’s eigenvector centrality and the distance to its nearest neighbor,nor between the coefficient of variation of similarity in call characteristics of a population and the average distance to all other ***,three acoustic clusters were identified by the Girvan-Newman algorithm,and clustering was partially associated with ***,the most central populations were included in the same cluster,but the top betweenness populations were located within different clusters,suggesting that centrality populations are not necessary bridging between *** results demonstrate the potential usefulness of the SNA toolbox and indicate that SNA helps to uncover the patterns that often overlooked in other analytical *** using SNA in frog’s call studies,researchers could further uncover the potential relationship in call characteristics between geographical populations,further reveal the effects of ecological factors on call characteristics,and probably enhance our understanding of the adaptive evolution of acoustic signals.

关键词： acoustic feature anurans Chiromantis doriae eigenvector centrality geographical population

Inter-group associations in Mongolian gerbils:Quantitative evidence from social network analysis

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Integrative Zoology 2017年第6期12卷 446-456页

作者： ke deng Wei LIU Dehua WANG State key Laboratory of Integrated Management of Pest Insects and Rodents Institute of ZoologyChinese Academy of SciencesBeijingChina and University of Chinese Academy of SciencesBeijingChina

Animals often interact non-randomly with conspecifics,and association preferences can differ across life-history stages to maximize individuals’*** gerbils(Meriones unguiculatus)are a social rodent that live in highly seasonal habitats and display seasonal fluctuations in population density,growth rate and the size of overlapped home ***,whether gerbils modify their social relationships at different life-history stages remains ***,we used social network analysis to examine whether social associations differ between the sexes and between life-history stages in a wild population of Mongolian *** quantified social attributes at both group level(assortativity)and individual level(social differentiation and degree,closeness and betweenness centrality);these attributes reflect individuals’social preferences and their potential influence on others in the *** found that both male and female gerbils established fewer inter-group social connections during the food-hoarding season than during the breeding season,revealing constraints on sociali***,during the food-hoarding season,degree centrality and social differentiation increased significantly whereas closeness and betweenness centrality decreased ***,these results suggest that gerbils have relatively more partners and preferred associations and decreased influence over others in the network during the food-hoarding *** addition,we found no significant difference in any of the social attribute between males and females,but there was a significant interaction effect between sex and season on degree,closeness and betweenness *** results demonstrate that Mongolian gerbils adjust their association strategies to adapt to the changes of life *** adjustments may balance the costs/benefits associated with survival and reproduction.

关键词： centrality inter-group associations life history Meriones unguiculatus social network analysis

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Current Zoology 2019年第5期65卷 527-534页

作者： ke deng Wei LIU De-Hua WANG State key Laboratory of Integrated Management of Pest Insects and Rodents Institute of ZoologyChinese Academy of SciencesBeijingChina Chengdu Institute of Biology Chinese Academy of SciencesChengduSichuanChina University of Chinese Academy of Sciences BeijingChina

Kin selection theory predicts that individuals should generally behave less aggressively or more amicably towards relatives than ***,how individuals treat conspecifics depends on genetic relatedness but also on the ecological context,which influences the benefits and costs of their *** this study,we used microsatellite DNA markers and behavioral tests to examine the influence of kinship and proximity on the social behavior of Mongolian gerbils Meriones unguiculatus living in different social groups,and whether these effects varied with sex and *** recorded the duration of 4 behavioral categories(investigative,neutral,amicable,and agonistic)during a 10-min pairwise *** found that genetic relatedness had significant effects on the duration of investigative,neutral,and amicable behavior,but not on agonistic *** also found significant interaction effects of relatedness and distance between burrow systems(i.e.,spatial distance)on investigative,neutral,and amicable behavior,which suggests that the effects of kinship on social behavior were restricted by spatial *** interaction effect between sex and relatedness on amicable behavior showed that male gerbils became more intimate with individuals of the same sex that had higher pairwise relatedness than ***,both male and female gerbils enhanced their aggression during the food-hoarding season,but the intensity of these changes was significantly higher in ***,our results suggest that the effects of kinship and spatial proximity on social behavior exhibit sexual or seasonal patterns,thereby implying ecological context-dependent responses to out-group individuals in Mongolian gerbils.

关键词： familiarity kinship Meriones unguiculatus seasonality social behavior

Stability control of steer by wire system based on μ synthesis robust control

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Science China(Technological Sciences) 2017年第1期60卷 16-26页

作者： WANG ChunYan deng ke ZHAO WanZhong ZHOU Guan ZHOU Dong State key Laboratory of Mechanical Transmission Chongqing University Chongqing 400044 China

The uncertainty influences may result in performance deterioration and instability to the steer by wire(SBW) system. Thus, it must make the control system keep robust stability from uncertainty, and have good robustness. In order to effectively restrain the interference and improve steering stability, this paper presents a μ synthesis robust controller based on SBW system, which considers the effect of model uncertainty and external disturbance on the system dynamics. Taking the ideal yaw rate tracking, interference suppression and excellent robustness as the control objectives, the μ synthesis robust controller is designed using linear fractional transformation theory to deal with the uncertainty. Then, it is testified through time domain and robustness simulation analysis. Simulation results show that the proposed controller can not only ensure robustness and robust stability of the system quite well, but improve handling stability of the vehicle effectively. The results of this study provide certain theoretical basis for the research and application of SBW system.

关键词： Vehicle steer by wire μ analysis and synthesis stability control robustness

Robust control for active suspension system under steering condition

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Science China(Technological Sciences) 2017年第2期60卷 199-208页

作者： WANG ChunYan deng ke ZHAO WanZhong ZHOU Guan LI XueSong Department of Automotive Engineering Nanjing University of Aeronautics and Astronautics State key Laboratory of Automobile Simulation and Control Jilin University

To minimize the auto body's posture change caused by steering and uneven road, and improve the vehicle's riding comfort and handling stability, this paper presents an H∞ robust controller of the active suspension system, which considers the effects of different steering conditions on its dynamic performance. The vehicle's vibration in the yaw, roll, pitch and vertical direction and the suspension's dynamic deflection in the steering process are taken into account for the designed H∞ robust controller, and it introduces the frequency weight function to improve the riding comfort in the specific sensitive frequency bands to human body. The proposed robust controller is testified through simulation and steering wheel angle step test. The results show that the active suspension with the designed robust controller can enhance the anti-roll capability of the vehicle, inhibit the changes of the body, and improve the riding comfort of the vehicle under steering condition. The results of this study can provide certain theoretical basis for the research and application of active suspension system.

关键词： vehicle active suspension system steering condition H∞ robust control sensitive frequency bands

Embedding differential privacy in decision tree algorithm with different depths

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Science China(Information Sciences) 2017年第8期60卷 136-150页

作者： Xuanyu BAI Jianguo YAO Mingxuan YUAN ke deng Xike XIE Haibing GUAN Shanghai key Laboratory of Scalable Computing and Systems Shanghai Jiao Tong University

Differential privacy(DP) has become one of the most important solutions for privacy protection in recent years. Previous studies have shown that prediction accuracy usually increases as more data mining(DM)logic is considered in the DP implementation. However, although one-step DM computation for decision tree(DT) model has been investigated, existing research has not studied the scenarios when the DP is embedded in two-step DM computation, three-step DM computation until the whole model DM computation. It is very challenging to embed DP in more than two steps of DM computation since the solution space exponentially increases with the increase of computational complexity. In this work, we propose algorithms by making use of Markov Chain Monte Carlo(MCMC) method, which can efficiently search a computationally infeasible space to embed DP into DT generation algorithm. We compare the performance when embedding DP in DT with different depths, i.e., one-step DM computation(previous work), two-step, three-step and the whole model. We find that the deep combination of DP and DT does help to increase the prediction accuracy. However, when the privacy budget is very large(e.g., ? = 10), this may overwhelm the complexity of DT model, and the increasing trend is not obvious. We also find that the prediction accuracy decreases with the increase of model complexity.

关键词： differential privacy decision tree exponential mechanism exhaustive search MCMC

THE FLOW PROBLEM OF FLUIDS FLOW IN A FRACTAL RESERVOIR WITH DOUBLE POROSITY

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Applied Mathematics and Mechanics(English Edition) 2001年第10期22卷 1118-1126页

作者： TONG deng-ke(同登科) Zhang Hong-qing(张鸿庆) Department of Applied Mathematics Petroleum University East of China Dongying 257061 P R China Institute of Mathematical Science Dalian University of TechnologyDalian 116024 P R China

The effective radius of oil well is introduced in the inner boundary in the problem of fluids flow through fractal reservoir with double porosity, and thus a new model is established. Taking the wellbore storage and steady-state skin effect into consideration, the exact solutions of the pressure distribution of fluids flow in fractal reservoirs with double porosity are given for the cases of an infinite outer boundary, a finite closed outer boundary and a bounded domain with the constant pressure outer boundary conditions. The pressure behavior of fractal reservoir with double porosity is analyzed by using a numerical inversion of the Laplace transform solution. The pressure responses of changing various parameters are discussed.

关键词： fractal double porous media seepage well test analysis