J Shanghai Jiaotong Univ Sci

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Reputation-Based Collaborative Spectrum Sensing Scheme in Cognitive Radio Networks

ZHAO Shi-kang (赵士康), HE Di (何迪), LI Wen-hua (李文化), ZHU Fu-sheng (朱伏生)

2011 (6): 641-647.
doi: 10.1007/s12204-011-1204-6

摘要 ( 2482 )

Collaborative spectrum sensing is
proposed to improve the detection performance in cognitive radio
(CR) networks. However, most of the current collaborative sensing
schemes are vulnerable to the interference of the malicious
secondary users (SUs). In this paper we propose a reputation-based
collaborative spectrum sensing scheme to improve the security of
cooperative sensing by mitigating the impacts of misbehaviors. The
fusion center calculates the reputation rating of each SU according
to their history reports to weight their sensing results in the
proposed scheme. We analyze and evaluate the performance of the
proposed scheme and its advantages over previous schemes in
expansibility and integrity. Simulation results show that the
proposed scheme can minimize the harmful influence from malicious
SUs.

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Optimization Design of Two-Stage Operational Amplifier with Frequency Compensation via Geometric Programming

LI Dan (李丹), RONG Meng-tian (戎蒙恬), SHU Guo-hua (殳国华)

2011 (6): 648-651.
doi: 10.1007/s12204-011-1205-5

摘要 ( 1527 )

An optimization design technique to
obtain global solution for a two-stage operational amplifier
(op-amp) with frequency compensation is presented. This frequency
compensation technique can adjust the equivalent resistance to
guarantee that the phase margin is stable even though circumstance
temperature varies. Geometric programming is used to optimize the
component values and transistor dimensions. It is used in this
analog integrated circuit design to calculate these parameters
automatically. This globally optimal amplifier obtains minimum power
while other specifications are fulfilled.

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A Selection Scheme for Optimum Number of Cooperative Secondary Users in Spectrum Sensing

LIN Ying-pei (林英沛), HE Chen (何晨), JIANG Ling-ge (蒋铃鸽), HE Di

2011 (6): 652-657.
doi: 10.1007/s12204-011-1206-4

摘要 ( 1540 )

An optimization scheme for choosing the
optimum number of secondary users in cooperative spectrum sensing
based on the cyclostationary feature detection with Neyman-Pearson
criterion is proposed in this paper. The optimal soft combination
test statistic for the cooperative spectrum sensing based on
cyclostationary feature detection is derived according to the
generalized likelihood ratio test and its corresponding detection
performance is deduced. A target function, considering two important
parameters as the resource use efficiency and the number of samples
employed by each cooperative secondary user in the system design, is
constructed to obtain the optimum number of cooperative secondary
users. It can be found that the selection scheme is to make a
tradeoff between the system complexity of the cognitive radio
network and the global sensing performance of the cooperative
spectrum sensing.

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An Efficient Threshold Key-Insulated Signature Scheme

CHEN Jian-hong (陈剑洪), LONG Yu (龙宇), CHEN Ke-fei (陈克非) WANG Yong-tao

2011 (6): 658-662.
doi: 10.1007/s12204-011-1207-3

摘要 ( 1383 )

To tackle the key-exposure problem in signature settings,
this paper introduces a new cryptographic primitive named threshold key-insulated
signature (TKIS) and proposes a concrete TKIS scheme．For a TKIS system, at
least k out of n helpers are needed to update a user's temporary private key.
On the one hand, even if up to k-1 helpers are compromised in addition to the
exposure of any of temporary private keys, security of the non-exposed
periods is still assured. On the other hand, even if all the n helpers are
compromised, we can still ensure the security of all periods as long as none
of temporary private keys is exposed. Compared with traditional
key-insulated signature (KIS) schemes, the proposed TKIS scheme not only
greatly enhances the security of the system, but also provides flexibility
and efficiency.

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Directed Proxy Signature in the Standard Model

MING Yang (明洋), WANG Yu-min (王育民)

2011 (6): 663-671.
doi: 10.1007/s12204-011-1208-2

摘要 ( 1745 )

restricted verification ability. Directed signatures
allow only a designated verifier to check the validity of the
signature issued to him, and at the time of trouble or if necessary,
any third party can verify the signature with the help of the signer
or the designated verifier. Directed signature schemes are widely
used in situations where the receiver's privacy should be protected.
Proxy signatures allow an entity to delegate its signing capability
to another entity in such a way that the latter can sign message on
behalf of the former when the former is not available. Proxy
signature schemes have found numerous practical applications such as
distributed systems and mobile agent applications. In this paper, we
firstly define the notion of the directed proxy signature by
combining the proxy signature and directed signature. Then, we
formalize its security model and present a concrete scheme in the
standard model. Finally, we use the techniques from provable
security to show that the proposed scheme is unforgeable under the
gap Diffie-Hellman assumption, and invisible under the decisional
Diffie-Hellman assumption.

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Chosen Ciphertext Secure Identity-Based Broadcast Encryption in the Standard Model

SUN Jin (孙瑾), HU Yu-pu (胡予濮), ZHANG Le-you (张乐友)

2011 (6): 672-676.
doi: 10.1007/s12204-011-1209-1

摘要 ( 1563 )

To give concurrent consideration both
the efficiency and the security (intensity of intractable problem)
in the standard model, a chosen ciphertext secure identity-based
broadcast encryption is proposed. Against the chosen ciphertext
security model, by using identity (ID) sequence and adding
additional information in ciphertext, the self-adaptive chosen
identity security (the full security) and the chosen ciphertext
security are gained simultaneously. The reduction of scheme's
security is the decisional bilinear Diffie-Hellman (BDH) intractable
assumption, and the proof of security shows that the proposed scheme
is indistinguishable against adaptive chosen ciphertext attacks in
the standard model under the decisional BDH intractable assumption.
So the security level is improved，and it is suitable for higher
security environment.

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Pre-emptive Channel Borrowing and Traffic Overflowing Channel
Allocation Scheme for Multimedia Overlay Networks

ZHAO Fang-ming (赵方明), HANG Juan (杭娟), HE Di (何迪)

2011 (6): 677-686.
doi: 10.1007/s12204-011-1210-8

摘要 ( 1207 )

This paper proposes a channel allocation
scheme for multimedia wireless networks, in which a two-layer
macro-cell or micro-cell architecture is considered. Macro-cells are
used to access high-mobility services; while micro-cells, which are
overlaid by the macro-cells, are used to cater low-mobility
services. To analyze the scheme, a multidimensional Markov traffic
model is firstly developed, in which traffic characteristic of two
special periods of time is considered. And then, a pre-emptive
channel-borrowing scheme combined with traffic-overflowing strategy
for multimedia (voice, video or data) networks is proposed, in which
handoff requests can not only borrow channels from adjacent
homogenous cells, but also be overflowed to heterogeneous cells.
Priority strategies are also dedicated to high-mobility services for
they can pre-empt channels being used by low-mobility services in
macro-cells. To meet the high quality of service (QoS) requirements
of video services and increase the channel utilization ratio, video
services can be transformed between real-time services and
non-real-time services as necessary. Simulation results show that
our schemes can decrease the blocking probabilities and improve the
channel utilization.

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Model and Simulation of a New Ultra-Narrow Trigger Frequency
Alterable Pulse Generator

YANG Yun-feng (杨运峰), CAO Zhen-xin (曹振新), YE Zhan(叶展), DOU Wen-bin (窦文

2011 (6): 687-690.
doi: 10.1007/s12204-011-1211-7

摘要 ( 1748 )

Two new kinds of ultra-narrow trigger
frequency alterable picosecond pulse generator are presented. One
can produce positive pulses and the other can produce negative
pulses. The two pulse generators are subdivided into three parts:
signal driving circuit, differentiator network and pulse shaping
circuit. The pulse shaping circuit is made of step recovery diode
(SRD) and short-circuit microstrip line. A positive pulse with width
of 54 ps (50% ---50% ), rising time of 30 ps (10% ---90% )
and falling time of 32 ps (90% ---10% ), and a negative pulse
with width of 54 ps (50% ---50% ), rising time of 30 ps
(90% ---10% ) and falling time of 30 ps (10% ---90% ) are
achieved in simulation. All of the components are ready-made and
inexpensive. They can be applied in ultra-wideband (UWB)
communication system, such as transmitters and receivers.

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Joint User and Antenna Selection for Multiuser MIMO Downlink with
Block Diagonalization

LIU Wei (刘伟), ZOU Jun (邹俊), LUO Han-wen (罗汉文), MA Ji-peng (马继鹏

2011 (6): 691-695.
doi: 10.1007/s12204-011-1212-6

摘要 ( 1519 )

User selection is necessary for
multiuser multiple-input multiple-output (MIMO) downlink systems
with block diagonalization (BD) due to the limited free spatial
transmit dimensions. The pure user selection algorithms can be
improved by performing receive antenna selection (RAS) to increase
sum rate. In this paper, a joint user and antenna selection
algorithm, which performs user selection for sum rate maximization
in the first stage and then performs antenna selection in the second
stage, is proposed. The antenna selection process alternately drops
one antenna with the poorest channel quality based on maximum
determinant ranking (MDR) from the users selected during the first
stage and activates one antenna with the maximum norm of projected
channel from the remaining users. Simulation results show that the
proposed algorithm significantly outperforms the algorithm only
performing user selection as well as the algorithm combining user
selection with MDR receive antenna selection in terms of sum rate.

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Optimal Linear Phase Finite Impulse Response Band Pass Filter Design Using Craziness
Based Particle Swarm Optimization Algorithm

SANGEETA Mandal, SAKTI Prasad Ghoshal, RAJIB Kar,

2011 (6): 696-703.
doi: 10.1007/s12204-011-1213-5

摘要 ( 2208 )

An efficient method is proposed for the
design of finite impulse response (FIR) filter with arbitrary pass
band edge, stop band edge frequencies and transition width. The
proposed FIR band stop filter is designed using craziness based
particle swarm optimization (CRPSO) approach. Given the filter
specifications to be realized, the CRPSO algorithm generates a set
of optimal filter coefficients and tries to meet the ideal frequency
response characteristics. In this paper, for the given problem, the
realizations of the optimal FIR band pass filters of different
orders have been performed. The simulation results have been
compared with those obtained by the well accepted evolutionary
algorithms, such as Parks and McClellan algorithm (PMA), genetic
algorithm (GA) and classical particle swarm optimization (PSO).
Several numerical design examples justify that the proposed optimal
filter design approach using CRPSO outperforms PMA and PSO, not only
in the accuracy of the designed filter but also in the convergence
speed and solution quality.

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Chaff Cloud Jamming Suppression Based on Wavelet Transform

ZHAO Hai-bo (赵海波), PEI Jin-ze (裴晋泽), ZHAO Lei-ming (赵雷鸣), HU Guang-ru

2011 (6): 704-707.
doi: 10.1007/s12204-011-1214-4

摘要 ( 1359 )

Radar target signals and chaff cloud
jamming signals have different characters by the wavelet transform.
The wavelet coefficients of radar target signals are highly
correlated with its near-and-near-scale wavelet coefficients,
however the correlativity between the wavelet coefficients of chaff
cloud jamming signals and its near-and-near scale wavelet
coefficients is less significant. Based on the binary-base discrete
wavelet transform and the correlation algorithm, the method of
target entropy to estimate standard variance of the jamming signals
and each scale is proposed to ensure reasonable threshold, to
suppress chaff cloud signals and finally to reconstruct mixed
signals by the improved spatially selective noise filtration (ISSNF)
method. The extensive simulation results show that the proposed
method can availably suppress chaff cloud jamming and decontaminate
target echo.

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Efficient Clustering and Simulated Annealing Approach
for Circuit Partitioning

SANDEEP Singh Gill, RAJEEVAN Chandel, ASHWANI Kumar Chandel

2011 (6): 708-712.
doi: 10.1007/s12204-011-1138-z

摘要 ( 1936 )

Circuit net list bipartitioning using
simulated annealing technique has been proposed in the paper. The
method converges asymptotically and probabilistically to global
optimization. The circuit net list is partitioned into two
partitions such that the number of interconnections between the
partitions is minimized. The proposed method begins with an
innovative clustering technique to obtain a good initial solution.
Results obtained show the versatility of the proposed method in
solving non polynomial hard problems of circuit net list
partitioning and show an improvement over those available in
literature.

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Improved Preimage Attack on 3-Pass HAVAL

ZHONG Jin-min (钟锦敏), LAI Xue-jia (来学嘉), DUAN Ming (段明)

2011 (6): 713-721.
doi: 10.1007/s12204-011-1215-3

摘要 ( 1748 )

HAVAL is a hash function proposed by
Zheng et al. in 1992, including 3-, 4- and 5-pass versions.
We improve pseudo-preimage and preimage attacks on 3-pass HAVAL at
the complexity of 2^ 172 and 2^ 209.6 , respectively, as
compared to the previous best known results: 2^ 192 and 2^ 225
by Sasaki et al. in 2008. We extend the skip interval for
partial-patching and apply the initial structure technique to find
the better message chunks, and combine the
indirect-partial-matching, partial-fixing and multi-neutral-word
partial-fixing techniques to improve the attacks based on the
meet-in-the-middle method. These are the best pseudo-preimage and
preimage attacks on 3-pass HAVAL.

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Fusion of Remote Sensing Images Based on Nonsubsampled Contourlet Transform and Region Segmentation

WU Yi-quan (吴一全), WU Chao (吴超), WU Shi-hua (吴诗婳)

2011 (6): 722-727.
doi: 10.1007/s12204-011-1216-2

摘要 ( 1797 )

The purpose of remote sensing images fusion is to produce a
fused image that contains more clear, accurate and comprehensive information
than any single image. A novel fusion method is proposed in this paper based
on nonsubsampled contourlet transform (NSCT) and region segmentation.
Firstly, the multispectral image is transformed to intensity-hue-saturation (IHS) system. Secondly, the panchromatic image and the component intensity of the multispectral image are
decomposed by NSCT. Then the NSCT coefficients of high and low frequency
subbands are fused by different rules, respectively. For the high frequency
subbands, the fusion rules are also unalike in the smooth and edge regions.
The two regions are segregated in the panchromatic image, and the
segmentation is based on particle swarm optimization. Finally, the fusion
image can be obtained by performing inverse NSCT and inverse IHS transform.
The experimental results are evaluated by both subjective and objective
criteria. It is shown that the proposed method can obtain superior results
to others.

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Micro-Electro-Mechanical-Sensor Inertial Navigation System-Assisted Global Navigation Satellite System Receiver Acquisition Scheme and Performance
Evaluation

YE Ping (叶萍), ZHAN Xing-qun (战兴群), ZHANG Yan-hua (张炎华)

2011 (6): 728-733.
doi: 10.1007/s12204-011-1217-1

摘要 ( 1540 )

When an aircraft moves under a low
carrier-to-noise ratio (CNR) or at a high speed, increasing the
sensitivity of global navigation satellite system (GNSS) receiver is
a goal quite hard to achieve. A novel acquisition scheme assisted
with micro-electro-mechanical-sensor (MEMS) inertial navigation
system (INS) is presented to estimate the Doppler caused by user
dynamics relative to each satellite ahead of time. Based on tightly
coupled GNSS/INS estimation algorithm, MEMS INS Doppler error that
can be achieved is first described. Then, by analyzing the mean
acquisition time and signal detection probability, the MEMS
INS-assisted acquisition capabilities in cold, warm and hot starts
are quantitatively determined and compared with the standard GNSS
acquisition capability. The simulations and comparisons have shown
that: the acquisition time in cold start can be shortened by at
least 23 s, the time in warm start can be shortened to 1 s and the
acquisition capability is improved 95%, and the reacquisition
time in hot start can be shortened by around 0.090 s and the
capability can be enhanced 40%. The results demonstrate the
validity of the novel method.

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Solving the Euclidean Steiner Minimum Tree Using Cellular
Stochastic Diffusion Search Algorithm

ZHANG Jin (张瑾), ZHAO Ya-liang (赵雅靓), MA Liang (马良)

2011 (6): 734-741.
doi: 10.1007/s12204-011-1218-0

摘要 ( 1555 )

The Euclidean Steiner minimum tree
problem is a classical NP-hard combinatorial optimization problem.
Because of the intrinsic characteristic of the hard computability,
this problem cannot be solved accurately by efficient algorithms up
to now. Due to the extensive applications in real world, it is quite
important to find some heuristics for it. The stochastic diffusion
search algorithm is a newly population-based algorithm whose
operating mechanism is quite different from ordinary intelligent
algorithms, so this algorithm has its own advantage in solving some
optimization problems. This paper has carefully studied the
stochastic diffusion search algorithm and designed a cellular
automata stochastic diffusion search algorithm for the Euclidean
Steiner minimum tree problem which has low time complexity.
Practical results show that the proposed algorithm can find approving results
in short time even for the large scale size, while exact algorithms need to cost several hours.

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Aero-Optical Characteristics of Supersonic Flow over Blunt Wedge
with Cavity Window

LI Bo (李波), LIU Hong (刘洪)

2011 (6): 742-749.
doi: 10.1007/s12204-011-1219-z

摘要 ( 1628 )

The optical rays that form the image of
an object and propagate a supersonic flow over a vehicle are
refracted by the density variations. A numerical analysis of the
aero-optical characteristics of supersonic flow over blunt wedge
with a cavity window is carried out. A hybrid method of Reynold
averaged Navier-Stokes and direct simulation Monte Carlo (RANS/DSMC)
is employed to simulate the flowfield. Refraction factor is
introduced to evaluate the flowfield's aero-optical characteristic.
The results show that mean flow's aero-optical effects are mainly
caused by the shock wave, the expansion wave and the turbulent
boundary layer. Fluctuation flow's aero-optical effects are mainly
caused by the turbulent boundary layer and the shock wave induced by
the cavity window. The aero-optical effects at the leading side of
window are caused by the mean density variations, while the effects
at the trailing side are caused by the density fluctuations.
Different draft angles of the cavity window are investigated. The
airborne optical devices of supersonic vehicle should be mounted in
the middle of the cavity window with a large draft angle.

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Structure-Borne Sound Attenuation at Corner Interface with Dynamic Vibration Absorber Attached

CHE Chi-dong (车驰东), CHEN Duan-shi (陈端石)

2011 (6): 750-758.
doi: 10.1007/s12204-011-1220-6

摘要 ( 1575 )

Structure-borne sound attenuation at corner interface of two plates with dynamic vibration absorber attached is investigated by wave approach. Equations governing transmission and reflection coefficients are deduced by introducing some non-dimensional coefficients, which help to reveal the physical sense inside and to simplify the analysis. Numerical investigation on vibration energy transmission of bending wave is carried out as well. The results from measurement and prediction show almost the same trends in the simplified experiment. It is found that energy transmission at corner interface depends greatly on whether the dynamic vibration absorber attached acts at resonance and is relatively lower right after the nature frequency of dynamic vibration absorber. Furthermore, the dynamic vibration absorber attached provides less energy transmission of bending wave than blocking mass at the end of ``passing band''.

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Sensitivity Analysis of Thermal Properties on Numerical Simulation
Results of Quenching Process

ZHOU Zhi-fang (周志方), GU Jian-feng (顾剑锋), WANG Xiao-yan (王晓燕), PAN J

2011 (6): 759-762.
doi: 10.1007/s12204-011-1221-5

摘要 ( 1446 )

A three-factor three-level orthogonal test project has been designed based on the numerical simulation of a Jominy quenching process. Then the data scattering effects of thermal conductivity and enthalpy of tested steel, as well as the heat exchange coefficients of the cooling media, on the results have been studied. The results can be used as a reference for choosing the input thermal parameter in finite element simulation of quenching, and for evaluating the simulation results.

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