- EI核心期刊
Internet of things is closely related to numerous fields. We first analyze basic concepts and features of
Internet of things, and compare the relationships among Internet of things, the ubiquitous network,
machine to machine, and the cyber physics system. Then, we introduce the ubiquitous sensor network
(USN) architecture designed by the International Telecommunication Union, and present research
proposals for Internet of things architecture. Furthermore, we summarize the key technologies of Internet
of things and propose the model of Internet of things technology system. Finally, the status of
standardization is concluded and several development proposals are suggested for Internet of things.
A Method of TimeFrequency Analysis for
FrequencyHopping Signals
To make an analysis and estimate the parameters of frequencyhopping signal, a timefrequency analysis method based on signal decomposition is proposed according to the
characteristics of frequencyhopping signals. And a multicomponent frequencyhopping
signal is firstly decomposed into multiple singlecomponent signals with a
group of bandpass filters. The WignerVille distribution (WVD) of each component is
sum up to form a new timefrequency distribution. Simulation shows that the new time
frequency analysis method can effectively suppress crossterm interference of frequencyhopping signals. Compared with the existings, this new method preserves a higher time
frequency resolution.
A TimeVarying Nonintegral Codebook with Nonuniform Quantization
The precoding codebook design with the spatialcorrelated channel is investigated. Termed as timevarying nonintegral codebook, a codebook scheme is presented for practical implementation. The
concept of codebook period is also proposed. The timevarying nonintegral codebook supports
various tradeoff options between the codebook size and the system capacity performance. I
t also includes the traditional fixed uniform codebook as a special mode. If the codebook period
is small, the estimation of the spatial correlation coefficient seems not accurate enough. However,
the chosen codebook includes the best precoding matrix, i.e. the timevarying nonintegral codebook
performs similarly as a traditional fixed codebook with larger size. If the spatial correlation coefficient
changes fast, the codebook period will be decreased to guarantee that the codebook can trace the
varying channel.
Principle and Dynamic Analysis of a NewType
Spherical Underwater Vehicle
The structural configuration, principle of work, performance parameter, dynamic models and
attitude hold control scheme of a newtype spherical underwater vehicle BYSQ2 are proposed.
BYSQ-2 has a thruster and a steering gear with dual drive , and can complete degree of freedom
（6DOF）movement in the inertial frame. Because of the unique structure, the dynamic models of the
thruster and the pullback weight are built respectively. The spherical hull's attitude hold control model
is linearized by approximation, and the swing angle of the inverted pendulum is controlled by self
adaptive fuzzy proportionintegraldifferential controller（PID）scheme. Simulation result illustrates
that the scheme can acquire satisfied dynamic and static performance.
An Optimal Dynamic Deployment of Paging Areas
for Mobile IP Networks
Hierarchical mobile IPv6 (HMIPv6), presented by the Internet Engineering Task Force
(IETF), is able to reduce signaling cost of mobile IPv6 (MIPv6) by introducing mobility
anchor point (MAP). HMIPv6, however, it does not show how to set a MAP and its MAP
domain. Based on the number of communication hops between a mobile node (MN)
and the MAP, a new strategy for choosing a MAP and constructing its MAP domain is
proposed to realize HMIPv6, in which the MAP and its domain are chosen dynamically.
In addition, IP paging with a programming problem model, which optimizes MAP
domains, i.e., paging areas, is introduced. Moreover, the condition under which signaling
cost is reduced by paging is given. Numeric analyses show that the cost of HMIPv6 can
be reduced by setting a suitable threshold of the number of hops.
RAKE Receiver with Carrier Coherent Demodulation for MultiPath Signals
Can not be accurately estimated，and existed in signal carriers of different paths, the Phase
difference leads to significant drop of power utilization rate of multi-path signals received by conventional
RAKE receiver (CLRAKE). A new RAKE receiver (CORAKE) that can separate multi-path signals in
carriers of different paths and implement carrier coherent demodulation is proposed. When received by
CORAKE, signal of each path is coherently demodulated. Phase difference between the local carrier and
carriers of corresponding received signals is zero, so that the defect of receiving due to the phase difference
among carries can be removed. Simulation shows that the CORAKE obtains better receiving signal
to noise ratio (SNR) gain.
Multi-Targets Attack Strategy Based on the Overlapping
Community Structure of Complex Networks
Inspired by the feature that most of the real world networks are made of interwoven overlapping
communities, a new multi-targets attack strategy is proposed. It helps reveal the influence of community
structure to the robustness of complex networks. By attacking the nodes with higher community member-ship, the new strategy can drastically alter the internal structures and the overlapping relations of several
communities, that will result in performance deterioration of the whole network. Simulations based on Kl-
emmEguíluz(KE) network and Internet AS network demonstrate the prominent performance of the new
strategy and reveal the unique behavior that the number of communities decreased rapidly under the new
attack strategy. Moreover, the comparison with the random attack strategy and the degree based attack
strategy indicate the highdestructive ability of the new technique to the structure and the performance of
the complex networks.
A Perception Model for Network Risk Using Danger-Theory
In order to effectively assess the risk of network risk, and to take effective prevention measures,
featuring with realtime and quantitative detection, a dangertheory and Antibodyconcentration based perception model for network risk is proposed. Based on dynamic selfsets, the mathematical model and dynamic equations for selftolerance and various antibody are
designed. The quantify description of antibody concentration is given. The candidate detector
is generated from both random and detector genelib. Furthermore, the vaccination
are introduced to enhance the active detection. Simulations are done to test the model. The
experiments prove that the model can detect the intrusion attacks effectively and evaluate the
risk of both host and network including each attack and the whole attacks. If the model is trans-formed properly, it also can be applied to the fields of virus detection and spam mail recognition.
To analyze the impact on the security of cryptographic algorithm produced by the mixed usage
of modulo 2n and exclusive OR (XOR), based on the consistent degree of these two operations
for commutative law, the computation formulas of the probability distribution of the noise function
and the square sum of the probability values are presented. And a new distinguishing attack on
Py is proposed, of which the data complexity is about 273.82.
Constructing Secure Routing Protocol Using Trust Model
To implement the authentication mechanism in mobile Ad Hoc networks with no fixed base
station or central node, a new dynamic trust model without any thirdparty certification server
is proposed. The neighbor nodes set up their routing information by mutual authenticating.
The scheme constructs a dependable Ad Hoc networks using such dynamic trust model.
Analysis results show that the new protocol enhances the security of network and increases
the efficiency of routing.
A sufficient and necessary condition that a quadratic polynomial function is a bent function was
presented by Ma W P, et al. in 2005. In the same year, Charpin P, et al proposed a sufficient and
necessary condition that a polynomial function is a quadratic semi-Bent function with three
trace terms in a paper. Corollary 5,6 of the former and Theorem 5,6 of the latter are not quite right
by further investigating these conditions. Based on the theory of quadratic polynomial over finite
fields, the correct conditions are presented. Moreover, some quadratic bent functions with three or
four trace terms are constructed. Finally, a new method for constructing bent functions in polynomial
forms is provided by using bent functions of two trace terms and permutation of polynomial.
A Risk Assessment Model Using Incomplete Attack Graphs Analysis
To solve the hysteresis problem of complete attack graphs analysis method, the existing attack
graphs analysis is researched. By importing uncertain and unknown information, an incomplete
attack graphs analysis (IAGA) method is proposed. A risk assessment model based on IAGA
(IAGARAM) is also proposed, that will prevent asset losses from real intrusion activities, and is
applicable to the business life cycle.
A Music Retrieval Research and Implementation of New Methods
A serial of improvements to implement music information retrieval is proposed, it extracts
the pitch with a improved YIN algorithm. A new “cabinet” post-treatment is put forward to
produce regular pitch sequence; a melody contour marker method and fuzzy matching
method is designed; a similarity measure system to complete the retrieval is defined as
well. Experiments show that the new process is an improvement of the traditional content-
based music retrieval.
To guarantee the fairness requirements of each user, we study the power allocation strategies
based on multi-user quality of service (QoS) constraints in amplify-and-forward wireless
relay networks, a new power allocation schemes is proposed to i) minimize the maximum
outage probability over all users, and ii) to maximize the minimum rate under the outage
probability and total power constraints. The power allocation schemes are formulated using
geometric programming (GP). Since GP problem is readily transformed into an equivalent
convex optimization problem, optimal solution can be obtained efficiently. Simulation show
that proposed schemes can efficiently guarantee the QoS requirement.
An Accelerate-Layer-Into Error Control Coding Method for Nand Flash
Because of limitation of the manufacturing technique condition, a Nand Flash
controller is required to handle the bits errors and to maintain the high data
accessing speed. By the analysis of the errorcorrection code (ECC) design meth
od, an acceleratelayerinto error control coding method is proposee to accele
rate the reading and writing process for Nand Flash. A Nand Flash controller
with embedded 4 bit is designed. Simulation shows that the method is effectivel
y reduce the memory data error correction time.
In order to establish and improve theoretical system of the compliant metamorphic mechanism,
the structural representation and configuration analysis are studied. A definition is given, and
component elements are analyzed. The structural schematic is provided to represent structural
characteristics. The representation method of topological graph and adjacency matrix is put
forward. In order to analyze configuration transformations on the compliant metamorphic mechanism
deeply, a mathematic operation method based on adjacency matrix is presented as well. Its effectiveness
and correctness of the method are proved by an example.
Queuing System M/M/1/T with Priority Mechanism Based on Living Time
he critical performance of air/ground data transmission precisely, on the basis of queue theory
M/M/1 with priority, is analyzed. The dropping method according to living time and constructs
the M/M/1/T model is introduced, and the scheduling algorithm is also researched. The
calculation and simulation results show that, the new scheduling algorithm improves the system’s
channel ratio, packet-passing ratio and latency.
The Influence of Magnetic Field on the Electron Ground State
Energy of Two-Dimensional Quantum Ring
In the framework of effective mass envelope function, by solving the single-band Schrdinger
equation, the ground state energy level of two-dimensional InAs/GaAs quantum ring is
calculated both in the absence and the presence of the magnetic field to analyze the electronic
structure of quantum ring nanomaterials. The relationships between the energy level
and the inner radius, outer radius, average radius and width of the ring are analyzed. It is indicated
that the magnetic field perpendicular to the plane of the quantum ring will evidently increase the
ground state energy. Moreover, the magnetic field makes the dependence of the energy level on
outer radius of the ring weaker, i.e. the level will keep in changeless if the outer radius exceeds a
critical value.
In order to avoid correlation weakening between sources when bit-planes are decoded
independently in distributed video coding (DVC), a joint bit-planes decoding (JBPD)
algorithm is proposed. The JBPD algorithm uses the decoded bit-plane results as
prior knowledge to decode other bit-planes to avoid correlation weakening between
sources when bit-planes are decoded independently. The algorithm also makes
full use of correlation between Wyner-Ziv frames and key frames. Therefore the ratedistortion performance of distributed video coding can be enhanced without increasing
decoding complexity. Simulations indicate that, compared with the independent bit-planes
decoding system, the proposed algorithm can achieve better bit-rate saving under the same
condition, its performance improves more apparently with the increase of quantization levels.
A New Selection Algorithm for Modulation and Coding
Scheme in TD-HSPA+ MU-MIMO System
For the downlink multiuser multiple input multiple output (MU-MIMO) scenario, in order to
improve the accuracy of modulation and coding scheme (MCS) in time division high speed
packet access plus system, an enhanced MCS selection algorithm is presented. By taking
account of the channel estimation for the last uplink transmission, a appropriate MCS is
selected after adjusting the feedback channel quality indicator (CQI). This algorithm takes
advantages of no additional controlling signaling and low computational complexity. Simulation
shows that significant performance enhancement can be achieved by this algorithm when UE
experiences severe inter-user interference.
On the Equivalent Keys of Multivariate Public Key Cryptography
The multivariate public key cryptosystem has the problem that multiple private keys correspond
to a common public key. This paper defines the Plus sustaining transformation and presents
its expression. The problem of equivalent keys in some multivariate public key cryptographic
schemes is investigated with the Plus sustaining transformation and other sustaining trans-
formations. It is proved that the equivalent-keys of the Square scheme can be obtained
only through the Big and the Frobenius sustaining transformation. The results show that the
private key space can be significantly reduced due to the fact that any given public key
corresponds to exponentially many private keys. Accordingly, to achieve the expected
security, we must choose larger system parameters in the multivariate public key cryptosystems.
Moreover, by utilizing the sparse normal form of affine transformations of private keys, we can
effectively reduce the computational complexity and the storage requirements.
To improve the efficiency and reduce rekeying cost of batch rekeying, marking based batch rekeying
(MBBR) algorithm is proposed. Based on MBBR algorithm, one-way hash function and exclusive
operation are used to compute new keys, and improved tree-based batch rekeying (ITBR) algorithm
is presented. New keys of all renewed nodes in the tree are computed firstly, and then all
rekeying messages are sent, which avoids the problem of out-of-sync between keys and data.
Server's rekeying cost is analyzed theoretically, and accurate computation models of rekeying
cost are established. Analysis shows the security of ITBR algorithm is strong, and simulation
results show that its average rekeying cost is 45.6% of MBBR algorithm's cost. So the rekeying
efficiency and communication performance is improved significantly when this algorithm
is applied.
A Complexity-Reduced Joint Transceiver Design for
Multiuser MIMO Downlink
A method to reduce the complexity of joint transceiver design based on minimum sum mean
square error (sum-MSE) criterion under the constraint of sum power for multiuser multiple-input
multiple-output (MIMO) is presented by transforming the conditional optimization problem into
unconditional optimization(it doesn’t need to solve the nonlinear high order equation to obtain
Lagrangian multiplier). Simulation results indicate that the proposed algorithm can effectively
reduce the computation complexity as well as improve the BER performance remarkably.
Simulation Test of Mobile Phone Dust Ingression
The normally used dust test could hardly reflect dust ingression in electric/electronic devices. A
new test method are discussed. Many factors such as air flowing, structure densification, electro-
magnetic and thermal characteristic of electronic devices and dynamic environments may affect
the ingression. The electro-magnetic model of finite element method is established for the evaluation the
electric effects on dust ingression. Some experiments analysis related to dynamic environment
effects on dust ingression are performed. It is shown that the air flowing, structure densification
and dynamic environment effects are the leading factors, thermal and electro effects can be ignored.
Finally, an improved test method is presented.
Analysis of Transmission Capacity of Ad Hoc Networks
with SBPC Strategy
To study the transmission capacity for Ad Hoc networks with different power control strategies,
signal-to-interference ratio (SIR) based power control (SBPC) is applied in Ad Hoc networks.
By using stochastic geometry，a new model is introduced, and an expressions to outage
probability and transmission capacity are derived. Simulation shows that, compared with the
power control strategy used before, using SIR based power control can greatly decreases the
outage probability, but increases the transmission capacity.
Fountain Codes Based on Modulo and Chaos
A new class of fountain codes named Chinese transform (CT) codes is proposed to solve the
problem of the efficient transmission in high speed wireless network. Different from existing
fountain codes based on Tanner graph and exclusive OR (XOR) operations, the encoding of CT
codes transforms finite original symbols into theoretically infinite encoding symbols which are
generated by integers selected uniformly from the set of primes which are then enveloped into
packets by chaotic position scrambling algorithm. When enough packets are received from these
packets, original symbols can be recovered according to the CT decoding algorithm with 100%
probability. Simulation is also shown.
A Zero-Watermark Technology with Strong Robustness
In order to enhance the robustness of roust watermark technology, a zero-watermark technology is
proposed based on discrete wavelet transformation (DWT) and singular value decomposition（SVD）. It conducts DWT with the original image, divides its low frequency band into blocks, and
conducts SVD with every block. Zero-watermark is derived by judging the parity of the first digit of the
biggest singular value in every block. Experiments show that it possesses strong robustness against
various attacks.
A smoothing-based additive-noise estimation method of static image based on local homogeneity
measurement is proposed. In order to enhance the difference of homogeneity measurement values
between pixels, Cauchy distribution function is selected as the kernel function for proposed meas-urement method of the image homogeneity. The anisotropic diffusion based smoothing method is
also used for extracting the real image boundaries. After excluding sub-images including real
boundaries of the whole image, the most homogeneous sub-images are determined according to
the defined threshold value. Then, standard deviation values of these sub-images are calculated. Finally,
the median value of these values is extracted as the estimated value of the image noise. Furthermore,
there is no need to involve with any human interaction in implementation of the proposed noise
estimation method. Experiments show that the proposed method possesses higher estimation accuracy
and better robustness for additive-noise estimation after comparing with other filter-based noise
estimation methods.
In order to solve the problem of the blind recognition of channel coding, a blind recognition method
of identifying (n-1)/n convolution code is proposed. Firstly, a mathematical model of blind recog-
nition is given, followed by a method of solving parity check matrix through decomposition of the mat-
rix constructed by the intercepted code. Meanwhile, by the elementary transform of the parity check
matrix, the blind recognition of convolution code can be achieved. Simulations show that the proposed
method can recognize the convolution code parameters effectively.
Effect of Initial TOD on the Gain Characters of Pulses Propagating Through a Fiber Amplifier
The effect of the third order dispersion (TOD) in ultrashort pulses on power gain characters of them after propagating through a fiber amplifier in a chirped pulse amplification (CPA) system is investigated numerically. The pulse amplification process is described by nonlinear timedependent radiation transfer equations. Simulations show that，when the energy of the input pulse is identical, the peak power gain for the pulse without TOD is smaller than that with positive TOD, but larger than that with negative TOD. And the difference between the gain values increases with the initial pulse energy.