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摘要：An algorithm using the complex imaging method is presented in this paper to calculate the effective inductances of RF CMOS spiral inductors,with the effect of eddy currents inside the conductive substrate taken into consideration.The basic idea is to view the distributed eddy currents as a lumped image of the source current flowing in the inductor's windings,except that the position of the image is a complex number.After constructing a PEEC(partial equivalent element circuit) with the partial capacitance and inductance matrices extracted,the AC port-parameters of the inductor can then be computed.The accuracy of the completed program based on the above algorithm,called SCAPE,has been verified through a number of examples and comparisons with popular softwares such as ASITIC from UC Berkeley and Momentum in Agilent's ADS.There is an apparent speed advantage with our program.  

摘要：In this paper a new method of removing trace ammonia (NH₃ and H₄⁺) from high purity water by using electrodeionization(EDI) was studied.The removing of ammonia from high purity water and its mechanism were investigated.The dependence of the effectiveness of removing ammonia (NH₃ and NH₄⁺) on electrical current,inlet conductivity,inlet flow rate and pH value was shown.After one EDI treament the total ammonia concentration was decreased from 208mg/L to 0.072mg/L.This method is also effective for removing NH4+ ion from water.After EDI treatment NH4Cl concentration was decreased from 20~100mg/L to below 0.026mg/L.This method giving ammonia concentration much less than the required concentration of ＜0.5mg/L for space water proved to be the most effective among other methods for removing trace ammonia in high pure water.The species configuration during removing ammonia from water was also investigated.  

摘要：A novel 100,000-system-gate FPGA architecture FDP100K(FDP:FPGA for Data-Path) is proposed.It is designed for data-path application.The programmable logic cell for FDP100K is a new mixture logic block with LUT and MUX.The programmable interconnect for FDP100K is organized as a novel hierarchy structure.The chip has taped out with SMIC 0.35um CMOS process.It includes 1024 logic cells and 128 programmable IO cells.The chip FDP100K is tested by cooperating with its software system FDE(FDE:FPGA Development Environment).The results show that all kinds of logic cells and interconnect resources work correctly and the chip can be used to download data-path circuits and other kinds of circuits correctly.  

摘要：To solve the time redundancy of FPD gray scale imaging process,the fractal principle is firstly applied to the FPD scanning system in this paper,and the optimal scanning architecture is educed and its fractal model is proposed.Firstly,an optimal topology is constructed for digital display system whose memory space is incised into several sub-partitions with different time dimensions.Then,we established the fractal scanning model used in "time gray scale" and "sub-partition" topology,and deduced the fractal dimension of FPD discrete space.Based on the fractal model,the self-similar fractal scanning of time gray scale is carried out in every sub-partition.This paper proved the optimization of the fractal scanning architecture in theory,and the experimental results also indicated that it could raise the scanning efficiency,improve the imaging quality apparently without changing the scanning frequency of current digital flat panel display systems.  

摘要：Artificial fish swarm algorithm (AFSA) is a stochastic global optimization technique proposed lately.After analyzing the disadvantages of AFSA,this paper presents a hybrid artificial fish swarm optimization algorithm based on mutation operator and simulated annealing.The method is divided into two phases:the AFSA with mutation operator is used to search for the optimum solution,and simulated annealing is applied to optimize the optimum solution.By adding the mutation operator to AFSA in the evolution process,the ability of AFSA to break away from artificial fish stochastic moving without a definite purpose or heavy getting together round the local optimum solution is greatly improved.The hybrid algorithm is as simple for implement as AFSA,but can greatly improve the ability of seeking the global excellent result and convergence property and accuracy.The feasibility and effectiveness of our approach was verified through testing by function and practical problem.The experimental results show that the proposed algorithm is significantly superior to original AFSA.  

摘要：A reconfigurable cipher chip,which can improve the security and flexibility,has good potential to become a vital component in the future security system.However,the throughput of most reconfigurable cipher chips is pretty lower than that of specific purpose chips.How to improve the throughput becomes more and more important.In this paper,based on the analysis about the reconfiguration of the DES,3DES and AES,we propose a reconfigurable architecture,which combines reconfiguration technology with pipeline,parallel structure.We also implement DES,3DES,AES algorithms based on the reconfiguration architecture.The simulations show that the throughput is 7Gbps for DES,2.3Gbps for 3DES and 1.4Gbps for AES under a 110MHz clock.Moreover,the comparison with other current designs shows that the solution proposed in this paper achieves better performance than other solutions,and thus is suitable to the design of reconfigurable cipher chips.  

摘要：The least-cost QoS multicast routing problem with delay,delay jitter,bandwidth,packet loss-constrained belongs to NP-complete problem.Its hard to get the global solution using the traditional algorithm.In this paper, we propose a new algorithm-GAACS to solve QoS multicast routing problem, whose cores are using the genetic algorithm to optimize the control parameters of the ant colony algorithm.Simulation results show that GAACS is superior to the genetic algorithm in quality and efficiency.  

摘要：Based on analyzing to the composing feature of the polygon road net,an effective algorithm of creating the topology of the polygon road net is proposed,and its design and implementation process is given detailedly.The basic thought of the algorithm is first to triangulate the polygon road net,then to create its media axis,finally to generate its topology structure.The experimental results show the algorithm presented in this paper is correct and effective.  

摘要：Autocorrelation and linear complexity are two independent criterions for measuring the pseudorandom properties of sequences.For the 2^<em>n-periodic pseudorandom sequences,we first present the relationship between autocorrelation and linear complexity.The relationship can be applied in the following two aspects:(1)Estimating/Evaluating the value of autocorrelation functions by the linear complexity;(2)Evaluating the correlation of a given sequence family by the linear complexity.Furthermore,for a sort of sequences with period 2^<em>n,we denote that the autocorrelation is related to linear complexity and k-error linear complexity.  

摘要：As for the discriminant analysis on nonlinear manifold,a geodesic Gabriel graph based local discriminant merging approach was proposed.Using geodesic distance to discover the intrinsic geometry of the manifold,the geodesic Gabriel graph was constructed to locate the critical local regions where the local linear discriminants would be learned.The global nonlinear discriminant was achieved by merging the multiple local discriminants.The soft margin criterion based merging algorithm assigned the best weight to each local discriminant in an iterative way and upgraded the detection accuracy stepwise.The superiority of this algorithm was confirmed by experiments both on synthesized data and face image set.  

摘要：As a new technology,mobile agent shows a wide application in the field of network technology.However,security has been one of the crucial problems in the employment of mobile agents.In order to protect mobile agent against malicious hosts,some approaches have been proposed in the literature.A new protection model based on a trusted element is presented in this paper.The trusted element,which differs from traditional trusted hardware such as smart card or co-processor,offers a third party service based on an encrypted circuit construction. Procedure of constructing encrypted circuit is introduced and the way to use the trusted service to protect mobile agent is also described.An application example is given to show how to use the new model at the end of the paper.  

摘要：Most architectures of wireless sensor networks (WSN) are built as homogeneous networks,where all sensor nodes have the same structure.But it is not suitable for cluster-based WSN.By using multi-antenna sensor nodes as cluster heads in wireless sensor networks,we import MIMO and SIMO communication modes into inter-cluster layer and inner-cluster layer when sensor nodes communicate with the head.We introduce the basic communication modes in inhomogeneous networks and discuss the realization.The power consumption and delay model of MIMO-based sensor networks are given.We verify that this model is better than homogeneous networks by analysis and simulations.  

摘要：To optimize node selections for grid jobs under de-centralized scheduling frameworks,the algorithm of random multi-start hill climbing is proposed.To make multiple start-points distributed uniformly in grids,each start-point is found according to exponential increase of iteration times of selecting neighbors randomly.To reflect reasonable scheduling requirements from users,the average bounded slowdown weighted by parallel computation capacity is used to evaluate node selections.By flexibly adjusting grid workload,the algorithm of random multi-start hill climbing is evaluated comprehensively.With grid load being not too light,the algorithm can effectively optimize node selections in the whole grid.  

摘要：Active Appearance Model (AAM) is an efficient method for extracting human facial features.It includes active appearance models and the fitting algorithm.Within all kinds of fitting algorithms,the inverse compositional algorithm is one of the most efficient algorithms.However the efficiency of the fitting algorithm will drop when some other objects occlude any parts of human face.An improved AAM fitting algorithm is presented.It not only keeps the superiority of the original inverse composition algorithm but also enhances the ability of anti-jamming.The experiments show that our algorithm can enhance the robustness of the AAM fitting algorithm and keep the useful information when fitting with occlusion.  

摘要：It's a key of software evolution to achieve available method of software change-trace.A whole trace-process framework of requirement change is drawn based on three tiers which are propagation & modeling,propagation path,and trace approach of requirement change.Record method about propagation of function-requirement change is addressed based on trace-matrix of change-source,of change-object and of change component.Implementation of change-trace based matrixcalculation is described,and a simple cost decision method of software change-implementation is brought forward.It is advantage to implement software maintenance as well as software evolution.  

摘要：We present a novel concurrent transmission MAC protocol for MANETs which enjoys the simple design of single-channel,single-transceiver and single-transmission power architecture.The proposed protocol inserts additional control gap between the transmission of control packets (RTS/CTS) and DATA packet,which allows a serious of RTS/CTS exchanges to take place before the possible multiple,concurrent data transmissions.To assure these concurrent data transmissions finishing correctly,the collision avoidance information is included in control packets.These information are used by neighboring nodes to determine whether begin their transmissions or not,as in traditional transmission power control schemes.Simulation results show that,compared with IEEE 802.11,significant throughput gain can be obtained by the proposed protocol.  

摘要：In view of the complex network character of Internet,the computing result of the relation of Internet standard entropy with time shows that Internet evolves from low level order to high level one.Furthermore,the order parameter was also obtained by computing according to the synergetics theory.However,the time series data of average nodes degree were reconstructed in phase space.The fractal dimension,maximum Lyapunov parameter and Kolmologorov entropy were also computed.The predictable time scale of the serial data was get from the above computation.Finally,in means of the analytical results,the time series data were preprocessed,and the average nodes degree of Internet in near months was predicated by means of chaos predicting.  

摘要：To develop new topology with more powerful ability to tolerate node-failure in wireless sensor network,the existing research regards fault-tolerance topology as the multiply connected graph,and use the connectivity of the graph as standard to evaluate the tolerance ability.In this paper,we argue that fault tolerance of topologies is not equivalence to connectivity of the multiply connected graph by illustrating some practical examples,and point out the following three questions should be answered.First,what is node-failure tolerance of topologies? Second,how to evaluate this tolerance ability? Third,which type of topologies is more tolerant in node-failure? Then we define the concepts of node-failure tolerance and the degree of fault-tolerance and intrusion-tolerance.Then these concepts are used to evaluate the tolerance performance of hierarchy structure of wireless sensor network,and the conclusion is achieved that intrusion-tolerance degree is increasing with the ratio of cluster head increasing in hierarchy structure,but fault-tolerance degree decreasing.  

摘要：In order to deal with the shortcomings of traditional schemes,a novel efficient distributed load-balancing scheme based on replicable resource was proposed.Instead of those traditional schemes,the paper proposed a novel scheme to classify the resource load of a system as exterior load,interior load and transmission load to be processed respectively.In addition,the paper presented a new conception of load directivity and utilized it in load balancing scheme.At last,scheme analysis and simulation results show that the scheme can efficiently balance load,decrease interior communication flux and restrain system load threshing.  

摘要：How to obtain location information of an unknown node precisely is a key problem of locating service under ubiquitous computing environment.The paper proposes and proves three theorems of location reference nodes placement according to the analysis of the location error produced during location using the polygon location method and the three important characteristics of Chaos Dynamics.Based on the three theorems,the location reference nodes selection algorithm (LRNS algorithm) is proposed by improving the traditional polygon location algorithm.The simulation results indicate that the reference nodes placement theorems and the LRNS algorithm can meet the requirements of ubiquitous terminals'real-time location and possesses the preferable location precision.  

摘要：Conic curve cryptosystem was first introduced by CAO Zhenfu in 1998.By now,the previous study on conic curve cryptosystem has been based on conic curve group in finite field GF(p).Since the hardware circuits are suitable for performing addition,multiplication,squaring and the inversion operations in a finite field GF(2ⁿ),the operations in finite field GF(2ⁿ) are typically easier to implement in hardware and software than their counterpart in finite field GF(p).In order to speed up the computation of conic curve cryptosystem,the conic curve group is extended from finite field GF(p) to finite field GF(2ⁿ),and the order of the conic curve group in finite field GF(2ⁿ) is given.In addition,this paper suggests to use conic curve group in finite field GF(2ⁿ) for realizing public-key cryptosystem,and presents the basic ElGamal public-key encryption scheme and the Digital Signature Algorithm (DSA) based on conic curve in finite field GF(2ⁿ).Security of public-key cryptosystem based on conic curve in finite field GF(2ⁿ) is analyzed.  

摘要：An ontology graph model,whi ch creates ontology adjacency matrix and ontology reachability matrix,is descri bed.Depending on matrix shift and calculation,rippleeffect of ontology evolut ion can be analyzed and its quantity can be ascertained.Every rippleeffect cau sed by ontology change operation is described.At the same time,approaches for calculating ontology element contribution,ontology cohesions and effect degree applied to every ontology element during ontology evolution,are provided.Rippl eeffect analysis for dependencyunknown ontology evolution is discussed,and a server model for ontology evolution is also provided.All are credible foundatio n for management,control,usage and evaluation of ontology evolution,and are f oundation for ontology evolution automation calculation in computer.  

摘要：Web-page classification is an important research direction of web mining and much more difficult than pure-text classification.The accuracy of web-page classification can be heightened by getting rid of noisy information embedded in web pages,and the idea is utilized by our proposed summarization-based web-page classification method.In the paper,three traditional web-page summarization methods are analyzed and improved,and the Content Body summarization method and an ensemble summarization method based on four summarization methods are proposed.A large amount of experimental results of web-page classification based on summarization show that all the summarization methods can improve the performance of web-page classification algorithms and the ensemble summarization method achieves a 12.9% improvement over pure-text based methods.  

摘要：The Main Optical Telescope (MOT) is a payload of the important solar observing satellite SST with features of complex control,large volume science data and high reliability.According to the requirements of electronic system and central electronic unit,this paper brings forward a strategy to deal with science data and control task separately and builds a distributed model.Reconfigurable design based on FPGA and LEON core and fault tolerant scheme were given.  

摘要：For efficient yield prediction and inductive fault analysis of integrated circuits,it is usually assumed that defects related to the photolithographic in the wafer surface have the shape of circular discs,ellipse or squares.Real defects,however,exhibit a great variety of different shapes,their shapes usually play an extremely important role in the yield prediction.The fractal characterizations of real defect outlines are discussed,and the fractal dimension is estimated by wavelet transform,the result is in agree with the actual feature.So it provides new feature parameters for the characterization and computer simulation of defect outline.  

摘要：A novel multi-agent reinforcement learning approach is proposed to learn the coordinated behaviors among cooperative agents team.The proposed approach combines advantages of the modular architecture,profit-sharing learning and opponent modeling technique in a single multi-agent framework.Simulation results on the pursuit problem show that the proposed learning approach has faster convergence speed and more optimal policy over conventional modular Q-learning algorithms.  

摘要：Multi-channel filter bank (MFB) is investigated systematically.A kind of nonsingular multi-channel filter banks (NMFB) is defined.The analysis equations,synthesis equations and transfer equations of NMFB are introduced.And the optimizing restrictions for normalizing,smoothing and symmetry of filters are discussed.Particularly,the concept of zero spectrum moment filters to optimize filter's character is proposed.At last the design procedure and example of symmetric multi-channel filter bank are given.  

摘要：The success of ISOMAP depends greatly on choosing a suitable neighborhood size,however,it is still an open problem how to do this effectively.Based on characteristics of the SOMST (Second-Order Minimal Spanning Tree) in which shortcut edges can be avoided,this paper presented a variant of ISOMAP,i.e.P-ISOMAP (Pruned-ISOMAP).P-ISOMAP can prune effectively shortcut edges existed possibly in the neighborhood graph according to their costs over the SOMST,and thus is much less sensitive to the neighborhood size than ISOMAP.Consequently,P-ISOMAP can be applied to data visualization more easily than ISOMAP for the open problem described above can be avoided to a certain extent;in addition,P-ISOMAP can also be more topologically stable and robust than ISOMAP.Finally,the feasibility and effectivity of P-ISOMAP can be verified by experimental results very well.  

摘要：The current IP network utilizes best-effort mechanism to satisfy bandwidth requirements,lacking of manageability and maintainability.The next generation IP networks should have the ability to allocate bandwidth efficiently to satisfy different QoS requests from different users and maximize the revenue for carriers.This paper proposes a generic revenue-based bandwidth allocation model and presents the RBA (Revenue-based Bandwidth Allocation) problem can be classified into FRBA(Flexible RBA) and SRBA(Strict RBA) problems.This paper proves that bandwidth allocation problem is equivalent to Knapsack problem and provides Enhanced Greedy Algorithm (EGA) to resolve it.The experiments on a 128Gbps distributed router show that EGA is fair and can be calculated in polynomial time.EGA has been implemented on the real-world network devices,which are running on the carrier's network.  

摘要：The Chan and Vese (C-V) model using one level set function can only represent one object and one background by the sign of the function and can not express the multiple junctions of multiple objects.To deal with the problem,a tree-like multiphase level set algorithm for segmentation based on the C-V model is proposed whose basic idea is changing the background in the image so that the level set function will detect new object in the observed image.A key technique,called the technique of painting background,is proposed following the theory of simultaneous brightness contrast.Moreover,a hieranchical procedure of the proposed algorithm using multiple level sets is developed for multiphase segmentation (n-1 level sets for n phases,n＞1).Experimental results show that the proposed algorithm can represent multiple junctions of regions (n-phase segmentation for at most representing n junctions) and detect multiple objects (n-phase segmentation for n-1 objects).Also,the algorithm is especially effective for images which have sub-objects in the object region.  

摘要：Based on a new expansion for pairs of integers called adaptive k-ary window expansion (k-AWE),a new Straus-Shamir-like method for computing g^ah^b is proposed.The average joint Hamming weight of the k-AWE is 3/(3k+1).Comparing with other methods,it is shown that the method can be on-line implemented more efficiently.At the same time,the optimal value for k is also precisely analyzed.Our result shows that k=3 is a best choice for cryptographic application of usual 512~2048 bits key size.  

摘要：For monolithic RF spiral inductor on high-loss silicon substrate,a novel physical model is proposed,in which functions of both skin effect and proximity effect to frequency-dependent series parameters L_s and R_s are accounted in the light of modified partial equivalent element circuit methodology and,in the meanwhile,complicated eddy current losses in the substrate are captured by a full-coupled transformer loop.Up to 20GHz,the model reveals quite good accuracy within 7% with data from full-wave electromagnetic filed simulator,including equivalent inductor L_eff,resistor R_eff and quality factor Q and,hopefully,it can be applied to further theory research and optimum design of RFIC spiral inductor on Si.  

摘要：A challenge was brought to the scheduling algorithm of TS multiplexers by time-slicing technology adopted in DVB-H.We proposes a scheduling algorithm based on variable bit rate (VBR) video traffic prediction for TS multiplexers in DVB-H networks.This algorithm allocates the bandwidth of next scheduling cycle in advance by the prediction of VBR video traffic,and meets the requirement about scheduling algorithm needed by the technology of time-slicing.Our scheduling algorithm can achieve significantly lower delay and higher utilization of bandwidth,in comparison with CBR scheduling algorithm.  

摘要：In the transcoding proxy based streaming media systems,CPU and network are potential bottleneck resources.In this paper,a resource-adaptive transcoding proxy caching mechanism is proposed,which deals with network and CPU demand in an integrated fashion and aims to improve the system's capability potentially.We first explore the network gain and CPU gain of caching multiple versions at the same time.By introducing a time-vary influence factor α (t),the aggregated resource gain of the caching system is derived.Then,we derive the merit function of caching a single object under a given caching status,and design the RAC cache replacement algorithm.The experimental result shows that RAC can achieve good resource-awareness and improved system throughput.  

摘要：As a novel simulated evolutionary algorithm which was proposed in recent years,ant colony optimization (ACO) algorithm has great capability in searching better solutions,but ACO also has the shortcoming of slow converging.For different dimensions of TSP problems,the paper studies the settings of parameters with experiments,and proposes a new method of the initialization of ants system.Experimental results indicate that the enhancement is practical.  

摘要：As continuously scaling down the VLSI technology,it is important to investigate the compatibility of the different advanced processes integrated together in advanced CMOS process.The impact of Ge-implantation on the work function of fully silicided NiSi (FUSI NiSi) gate is investigated.The flat band voltage (VFB) and Equivalent Oxide Thickness (EOT) data were determined by fitting the measured capacitance-voltage (C-V) curves with simulation curves.The results show that work functions of NiSi gates with and without Ge implantation vary slightly,less than 0.03eV.The increase of interface state and fixed oxide charge introduced by Ge preamorphization implantation is not observed.These results demonstrate that FUSI NiSi gate technology can be integrated with Ge preamorphization implantation in self alignment CMOS process.  

摘要：The rapid advance in communication technology brings a request for cryptography systems of higher performance.We systematically implement and compare several variants of partly parallel systolic architecture for Montgomery multiplier with different bit length as well as with different micro architectural approaches.The optimal options are chosen to take advantage of the underlying technology.The result analysis shows that the fully serial systolic architecture,in which one cell processes one bit,achieves the best performance.When the resource overhead is represented as area-time product,it is one of the most cost-efficient designs as well.  

摘要：An efficient nonlinear subspace learning method,kernel neighborhood preserving projections (KNPP),is developed.The main idea is to approximate the classical local linear embedding (LLE) by introducing a linear transformation matrix and then find the solution in a very high dimensional space by kernel trick.The actual computation of the subspace is reduced to a standard eignenvalue problem rather than the generalized one.Experiments on AR face database demonstrate the effectiveness of the proposed method.  

摘要：In order to solve peer selection problem in unstructured P2P,size-Varied Measurement (VM) and size-Fixed Measurement (FM) using cache are provided.Moreover,four caching strategies are investigated: Random Drop (RD),Largest Latency Drop (LLD),Earliest Timestamp Drop (ED) and Least Use Drop (LUD).Finally,our experimental results show the following observations: FM greatly outperforms VM,LLD and LUD are prior to others,our schemes are stable when the rate of topology change is below 5%,and concurrent measurement can sharply reduce the peer selection latency.  

摘要：A test structure to measure the diffusivity of polysilicon thin films is proposed.The radiant heat loss and the convective heat loss from the structure have been considered.The same heating constant current is applied in the two beams,with the same width and thickness but variant length.The change of resistance with time up to thermal steady state is measured using a separation circuit,and then thermal diffusivity can be obtained.The model has been verified by ANSYS.The experiments show a thermal diffusivity of 1.059×10^-5±3×10-6m²/s.