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    TDRM: A Peer-to-Peer-Based Taxonomy Data Ring Model
    QIAO Bai-you (乔百友), WEI Yong (魏勇), WANG Xiao-yang (王潇杨) DING Lin-lin (丁琳琳), WANG Guo-ren (王国仁)
    Journal of shanghai Jiaotong University (Science)    2012, 17 (2): 182-189.   DOI: 10.1007/s12204-012-1250-8
    Abstract11793)            Save
    Peer-to-peer (P2P) networks are widely used due to their good scalability and robustness. This paper considers the characteristics of data sources which use some taxonomy hierarchies to classify and organize their data objects, combines P2P techniques, and proposes a P2P based taxonomy data ring model (TDRM). The model makes full use of the semantic information contained in taxonomy hierarchies, places the data objects having similar semantics together, and organizes them into one dimensional ring structure. Super-peers dynamically join the ring according to the requirement. The routing connections among super-peers are created, which are similar to Chord ring, thus a semantics based structured super-peer network is formed. Experiments show that the model has good scalability and search efficiency.
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    Simple Three-Party Password Authenticated Key Exchange Protocol
    LO Nai-wei (罗乃维), YEH Kuo-hui (叶国晖)
    Journal of shanghai Jiaotong University (Science)    2011, 16 (5): 600-603.   DOI: 10.1007/s12204-011-1195-3
    Abstract6771)            Save
    Abstract:  Three-party password authenticated key exchange (3PAKE)
    protocol plays a significant role in the history of secure communication
    area in which two clients agree a robust session key in an authentic manner
    based on passwords. In recent years, researchers focused on developing
    simple 3PAKE (S-3PAKE) protocol to gain system efficiency while preserving
    security robustness for the system. In this study, we first demonstrate how
    an undetectable on-line dictionary attack can be successfully applied over
    three existing S-3PAKE schemes. An error correction code (ECC) based S-3PAKE
    protocol is then introduced to eliminate the identified authentication
    weakness.
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    Comparison of Osteogenesis Between Two Kinds of Stem Cells from Goat
    Combined Calcium Phosphate Cement in Tissue Engineering
    ZHAO Wei (赵 伟), LU Jia-yu (陆家瑜), HAO Yong-ming (郝永明), ZHANG Xiu-li (张秀丽) QU Xiao-hui (瞿晓辉), HUA Li (华 丽), CAO Chun- hua (曹春花), ZOU De-rong (邹德荣)
    Journal of shanghai Jiaotong University (Science)    2011, 16 (5): 628-635.   DOI: 10.1007/s12204-011-1200-x
    Abstract2569)            Save
    Abstract:  To explore the possible mechanism of osteogenesis for deciduous
    teeth stem cells (DTSCs) in vivo/ vitro, stem cells from goat deciduous
    teeth (SGDs) were firstly isolated, induced and transplanted into
    immunocompromised mice. The SGDs's mineralization pattern and osteogenesis
    were compared with bone marrow messenchymal stem cells (BMMSCs) from goats.
    SGDs have similar osteogenic differentiation pattern in vitro and bone-like
    tissue formation mechanism in vivo to BMMSCs; moreover SGDs have stronger
    alkaline phosphatase (ALP) gene expression and osteopontin (OPN)
    gene expression levels than BMMSCs; also SGDs can form more bone-like
    tissues than BMMSCs when cell-scaffold compounds are transplanted into
    immunocompromised mice. This pre-clinical study in a large-animal model
    confirms that DTSCs may be an appropriate source of stem cells in repairing
    bone defects with tissue engineering.
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     Looper-Tension  H Control for Hot Strip Finishing Mills
    WANG Jing-cheng (王景成), ZHONG Zhao-zhun (仲兆准)
    Journal of shanghai Jiaotong University (Science)    2011, 16 (5): 519-523.   DOI: 10.1007/s12204-011-1188-2
    Abstract2509)            Save
    Abstract:  The development of an innovative H∞ controller for
    looper and tension control in hot strip finishing mills is traced based on
    approximately linearized model. This solution has been considered thanks to
    its well-known robustness and simplicity characteristics concerning
    disturbances' attenuation. The controller is designed based on an
    optimal problem with linear matrix inequality (LMI) constraints, and the problem is
    solved by the mincx function of Matlab LMI Toolbox. Simulation results show
    the effectiveness of the proposed controller compared with conventional
    ones.
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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)
    Journal of shanghai Jiaotong University (Science)    2011, 16 (6): 641-647.   DOI: 10.1007/s12204-011-1204-6
    Abstract2441)            Save
     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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    Super-Capacitive Performances of Nickel Foam Supported CeO2 Nanoparticles
    HU Ye-min* (胡业旻), SHI Tao-tao (史涛涛), NI Jian-sen (倪建森), JIN Hong-ming (金红明), ZHU Ming-yuan (朱明原), LI Ying (李瑛), BAI Qin (白琴)
    Journal of shanghai Jiaotong University (Science)    2012, 17 (5): 513-516.   DOI: 10.1007/s12204-012-1316-7
    Abstract2352)            Save
    This paper designs and fabricates CeO2 nanoparticles on a large scale by hydrolysis and oxidation of cerium carbide. The electrochemical supercapacitor behavior of CeO2 nanoparticles was investigated. The nickel foam (NF) supported CeO2 nanoparticles show a high areal capacitance of 119 mF/cm2, demonstrating a strong synergistic effect between NF and CeO2 nanoparticles. The high capacitance of the CeO2/NF nanoparticles is possibly due to an improved conductivity by NF and a better utilization of CeO2 nanoparticles.
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    Effect of Oxygen Content on Structural and Optical Properties of Single Cu2O Film by Reactive Magnetron Sputtering Method
    LI Bin-bin1,2*(李斌斌), ZHU Jian-xun2 (朱建勋), CHEN Zhao-feng1 (陈照峰), SHEN Hong-lie1 (沈鸿烈), LUO Jian1 (罗建)
    Journal of shanghai Jiaotong University (Science)    2012, 17 (5): 523-526.   DOI: 10.1007/s12204-012-1318-5
    Abstract2260)            Save
    Cuprous oxide (Cu2O) thin films have been deposited on glass substrate by reactive magnetron sputtering method using Cu target and argon oxygen gas atmosphere. Effect of oxygen flow rate on structural and optical properties of thin films has been discussed. The results of X-ray diffraction, ultraviolet-visible spectrophotometry and atomic force micrograph indicated that the condition window for single Cu2O phase was about 3.8 to 4.4 cm3/min, and the optimum oxygen flow rate was 4.2 cm3/min. The optical band gap Eg of Cu2O film was determined by using the data of transmittance versus wavelength, and slightly decreased from 2.46 to 2.40 eV with the increase of oxygen flow rate from 3.8 to 4.4 cm3/min. The Cu2O film formed at the oxygen flow rate of 4.2 cm3/min had an optical band gap of 2.43 eV.
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    Accurate 3D Reconstruction of Subject-Specific Knee Finite Element Model to Simulate the
    Articular Cartilage Defects
    DONG Yue-fu (董跃福), HU Guang-hong (胡广洪), ZHANG Luo-lian (张罗莲), HU Yang (胡 杨) DONG Ying-hai (董英海), XU Qing-rong
    Journal of shanghai Jiaotong University (Science)    2011, 16 (5): 620-627.   DOI: 10.1007/s12204-011-1199-z
    Abstract2252)            Save
    Abstract:  The biomechanical relationship between
    the articular cartilage defect and knee osteoarthritis (OA) has not
    been clearly defined. This study presents a 3D knee finite element
    model (FEM) to determine the effect of cartilage defects on the
    stress distribution around the defect rim. The complete knee FEM,
    which includes bones, articular cartilages, menisci and ligaments,
    is developed from computed tomography and magnetic resonance images.
    This FEM then is validated and used to simulate femoral cartilage
    defects. Based on the obtained results, it is confirmed that the 3D
    knee FEM is reconstructed with high-fidelity level and can
    faithfully predict the knee contact behavior. Cartilage defects
    drastically affect the stress distribution on articular cartilages.
    When the defect size was smaller than 1.00 cm2, the stress
    elevation and redistribution were found undistinguishable. However,
    significant stress elevation and redistribution were detected due to
    the large defect sizes (≥1.00 cm2. This alteration of
    stress distribution has important implications relating to the
    progression of cartilage defect to OA in the human knee joint.
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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,
    Journal of shanghai Jiaotong University (Science)    2011, 16 (6): 696-703.   DOI: 10.1007/s12204-011-1213-5
    Abstract2186)            Save
     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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    Skin Detection Method Based on Cascaded AdaBoost Classifier
    LU Wan (吕皖), HUANG Jie (黄杰)
    Journal of shanghai Jiaotong University (Science)    2012, 17 (2): 197-202.   DOI: 10.1007/s12204-012-1252-6
    Abstract2173)            Save
    Skin detection has been considered as the principal step in many machine vision systems, such as face detection and adult image filtering. Among all these techniques, skin color is the most welcome cue because of its robustness. However, traditional color-based approaches poorly perform on the classification of skin-like pixels. In this paper, we propose a new skin detection method based on the cascaded adaptive boosting (AdaBoost) classifier, which consists of minimum-risk based Bayesian classifier and models in different color spaces such as HSV (hue-saturation-value), YCgCb (brightness-green-blue) and YCgCr (brightness-green-red). In addition, we have constructed our own database that is larger and more suitable for training and testing on filtering adult images than the Compaq data set. Experimental results show that our method behaves better than the state-ofthe- art pixel-based skin detection techniques on processing images with skin-like background.
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    Research on Logistics Network Infrastructures Based on DEA-PCA Approach: Evidence from the Yangtze River Delta Region in China
    JU Chun-hua (琚春华), JIANG Chang-bing (蒋长兵), CHEN Ming-yao (陈明瑶)
    Journal of shanghai Jiaotong University (Science)    2012, 17 (1): 98-107.   DOI: 10.1007/s12204-012-1235-7
    Abstract2077)            Save
    Abstract: Compared with the extensive research on logistics network infrastructures (LNIs) in the developed world, empirical research is still scarce in China. In this paper the theory of LNIs is firstly overviewed. Then a new evaluation index system for LNIs is set up which contains factors that reflect the economic development level, transportation accessibility and turnover volume of freight traffic. An empirical study is carried out by using data envelopment analysis (DEA) and principal component analysis (PCA) approach to classify LNIs into 4 clusters for 25 cities in the Yangtze River Delta Region of China. According to the characteristics of the 4 clusters, suggestions are proposed for improving their LNIs. Finally, after comparing different LNIs of 25 cities in the Yangtze River Delta Region of China, this paper proposes that different LNIs including hub, central distribution center or cross docking center, regional distribution center or distribution center should be built reasonably in order to meet the customer's requirement in the four different cluster cities.
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    Microstructure of Hot-Dip Galvanized Zn-Al-Mg Alloy Coating
    YU Kang-cai1,2 (余康才), LI Jun2* (李俊), LIU Xin2 (刘昕), LI Jian-guo1 (李建国), XUE Xiao-huai1* (薛小怀)
    Journal of shanghai Jiaotong University (Science)    2012, 17 (6): 663-667.   DOI: 10.1007/s12204-012-1342-5
    Abstract2046)            Save
    The microstructure of hot-dip galvanized Zn-11%Al-3%Mg-0.2%Si alloy coating was studied in this article. X-ray diffraction analysis revealed the coating is composed by Zn, Al andMgZn2 phase. Optical microscope (OM) and scanning electron microscope (SEM) observations showed the coating is occupied by snowflake-like dendrite, double hexagonal organization and eutectic. The coating backbone was the dendrite considered to be a phase of hexagonal close-packed (HCP) structure judging form its morphology according to the crystal growth way in the coating. Transmission electron microscopy (TEM) and energy dispersive spectroscopy (EDS) researches on the dendrite suggested that an intermediate Zn-Al phase was formed at high temperature, then decomposed into a type of Zn-Al granular eutectoid after cooling down to room temperature, while the eutectoid Zn and Al had a certain crystallographic relationship. The coating solidification process and the grain crystal structure were discussed.
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    Simultaneous Localization and Mapping of Autonomous Underwater Vehicle Using Looking Forward Sonar
    ZENG Wen-jing (曾文静), WAN Lei (万 磊), ZHANG Tie-dong (张铁栋), HUANG Shu-ling (黄蜀玲)
    Journal of shanghai Jiaotong University (Science)    2012, 17 (1): 91-097.   DOI: 10.1007/s12204-012-1234-8
    Abstract2040)            Save
    Abstract: A method of underwater simultaneous localization and mapping (SLAM) based on on-board looking forward sonar is proposed. The real-time data flow is obtained to form the underwater acoustic images and these images are pre-processed and positions of objects are extracted for SLAM. Extended Kalman filter (EKF) is selected as the kernel approach to enable the underwater vehicle to construct a feature map, and the EKF can locate the underwater vehicle through the map. In order to improve the association efficiency, a novel association method based on ant colony algorithm is introduced. Results obtained on simulation data and real acoustic vision data in tank are displayed and discussed. The proposed method maintains better association efficiency and reduces navigation error, and is effective and feasible.
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    Grafting Watermelon Seedling Production Management System Based
    on Process Control Strategy
    KE Shun-kuia,b(柯顺魁), DING Mingb(丁明), LI Leia,b (李磊) NIU Qing-liangb (牛庆良), HUANG Dan-fengb* (黄丹枫)
    Journal of shanghai Jiaotong University (Science)    2012, 17 (2): 129-134.   DOI: 10.1007/s12204-012-1241-9
    Abstract2027)            Save
    Greenhouse environmental management, seedling bed scheduling, and fertilizer and water management
    are the core technologies of seedling nursery. Precision management and control of the whole production process
    guarantees high grated seedling quality. In order to improve management efficiency of grafted watermelon seedling
    production and seedling quality, this paper designs and develops a grafted watermelon seedling production management
    system based on process control methods by process control strategy, seedling bed planning design, and
    handheld device technology.
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    Flexural Experimental Study on Continuous Reinforced Concrete Beams Strengthened with Basalt Fiber Reinforced Polymer/Plastic
    OUYANG Li-juna,b* (欧阳利军), LU Zhou-daoc (陆洲导), CHEN Wei-zhenb (陈惟珍)
    Journal of shanghai Jiaotong University (Science)    2012, 17 (5): 613-618.   DOI: 10.1007/s12204-012-1333-6
    Abstract2006)            Save
    This paper discusses a new fibrous composite known as continuous basalt fiber reinforced polymer/ plastic (BFRP). Compared with other fiber reinforced polymer/plastic, BFRP has many advantages, such as ductility, high thermal resistance, corrosion resistance and economic cost. To test mechanical properties and failure modes of flexural members strengthened with BFRP, flexural experiment is conducted on four two-span T-section continuous beams strengthened with BFRP and one un-strengthened comparative beam. The experimental result shows that the strengthened beams perform remarkably in terms of yield strength, ultimate strength and ductility. BFRP has good prospects in retrofitting and strengthening of concrete structures which require good ductility and corrosion resistance.
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    Microstructure and Property of Friction Stir Welding Joint of 7075Al and AZ31BMg
    LI Da1,2 (李达), CUI Zhan-quan2 (崔占全), YANG Qing-xiang2* (杨庆祥),SUN Bing1 (孙兵), SUN Ming-hui2 (孙明辉)
    Journal of shanghai Jiaotong University (Science)    2012, 17 (6): 679-683.   DOI: 10.1007/s12204-012-1345-2
    Abstract1984)            Save
    Microstructure and forming quality of friction stir welding joints of 7075Al and AZ31BMg with different welding parameters were analyzed. The results show that, good welded joint is obtained when the rotating frequency is 13 r/s and the welding speed is 30 mm/min. An irregular area is formed in the welding center. Meanwhile, the river pattern and eddy-like distribution are found in the weld nugget zone. Besides, brittle intermetallic compounds Al12Mg17 and Al3Mg2 are found in the welded joint. They cause the increase of microhardness of welded joint. The maximum tension stress of welded joint is 112MPa.
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    Significance of Sacroiliac Joint Aerocele in Diagnosis of Ankylosing
    Spondylitis
    WANG Feng (王 锋), ZHAO Bing-hui (赵炳辉), WANG Nian-song (汪年松)
    Journal of shanghai Jiaotong University (Science)    2011, 16 (5): 636-640.   DOI: 10.1007/s12204-011-1201-9
    Abstract1977)            Save
    Abstract:  To explore the significance of sacroiliac joint aerocele in
    the diagnosis of ankylosing spondylitis, the data of 196 patients with ankylosing spondylitis (AS) were collected during December of 2008 to May
    of 2009. And 50 patients with osteoarthritis (OA), 15 patients with
    sclerosing osteitis (SO) and 47 patients with sacroiliac joint tumors were
    investigated as the control groups. The feature of sacroiliac joint aerocele
    in computed tomography (CT) images was observed carefully. In AS group
    there were 130 patients (66.3%) diagnosed as AS according to CT
    results, and 32 of them (24.6%) were observed with aerocele within
    sacroiliac joint cavity, majority of whom were earlier AS patients with
    slight bone destruction. Other 66 patients were diagnosed as early AS
    according to magnetic resonance imaging (MRI) and ultrasonography. CT
    examination showed that the 66 patients did not have apparent bone
    destruction, of whom, 26 (39.4%) patients had aerocele within sacroiliac joint
    cavity. Among the control groups of 15 (15/50, 30.0%) patients with OA, 5
    (5/15, 33.3%) patients with SO were observed sacroiliac joint aerocele. The 47
    patients with sacroiliac joint tumors were observed with bone or cartilage
    destruction, but without signs of sacroiliac joint aerocele. The sacroiliac
    joint aerocele in CT images of AS patients usually appeared as spots,
    streaks, small or larger round blocks, and it often happened in patients
    with earlier stage of diseases. Sacroiliac joint aerocele may be useful to
    early diagnosis of AS.
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    Composition-Dependent Mechanical and Thermal Transport Properties of Carbon/Silicon Core/Shell Nanowires
    JING Yu-hanga,b* (荆宇航), YU Kai-pinga (于开平), QIN Xiana (覃弦), SHEN Junb* (沈军)
    Journal of shanghai Jiaotong University (Science)    2012, 17 (6): 743-747.   DOI: 10.1007/s12204-012-1357-y
    Abstract1950)            Save
    Abstract: Molecular dynamics (MD) simulations are performed to study the composition-dependent elastic modulus and thermal conductivity for carbon/silicon core/shell nanowires (NWs). For each concerned carbon/silicon core/shell NW with a specified diameter, it is found that elastic modulus is reduced with a linear dependence on cross-sectional area ratio. The fact matches well with the results of theoretical model. Analysis based on the cross-sectional stress distribution indicates that the core region of core/shell NW is capable of functioning as a mechanical support. On the other hand, thermal conductivity also relies on the cross-sectional area ratio of amorphous silicon shell. The core/shell interface plays a considerable influence on the thermal transport property. The decreasing rate of thermal conductivity is gradually decreased as the composition of amorphous silicon shell increases. In addition, by calculating the phonon density of state, we demonstrate that the reduction in thermal conductivity of the core/shell NW stems from the increase of the low frequency modes and the depression of high-frequency nonpropagating diffusion modes. These results provide an effective way to modify the properties of core/shell NWs for related application.
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    Effects of Micro-arc Oxidation Coating on Corrosion Behavior of Mg-Y-Zn in Simulated Body Fluid
    LU Tian-feng (卢天凤), YIN Kai-yang (尹恺阳), SUN Bing-yi (孙秉毅),DONG Qing (董晴), CHEN Bin* (陈彬)
    Journal of shanghai Jiaotong University (Science)    2012, 17 (6): 668-672.   DOI: 10.1007/s12204-012-1343-4
    Abstract1949)            Save
    The application of magnesium and its alloy as degradable biomaterials is mainly confined due to its high degradation rate in physiological environment. This research focused on the effects of micro-arc oxidation (MAO) on biodegradable behavior of Mg-Y-Zn magnesium alloy in a simulated body fluid (SBF). The corrosion rate of alloys was gauged by means of hydrogen evolution volume measurement and mass-loss method. Scanning electron microscope (SEM) was utilized to observe the surface of the magnesium alloy and the cross-section of oxidation coating layer before and after corrosion. The Mg-Y-Zn alloy with thicker oxidation coating exhibited greater corrosion resistance during the immersion test for 240 h.
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    Comments on Enhanced Yoking Proof Protocols for Radio Frequency
    Identification Tags and Tag Groups
    CHIEN Hung-yu (简宏宇), YEH Ming-kuei (叶明贵), WU Tzong-chen (吴宗成), LEE Chin-i (李静怡)
    Journal of shanghai Jiaotong University (Science)    2011, 16 (5): 604-609.   DOI: 10.1007/s12204-011-1196-2
    Abstract1915)            Save
    Abstract:  A radio frequency identification (RFID) yoking proof scheme can generate
    proofs of simultaneous presence of two tags in the range of a specified
    reader so that an off-line verifier can verify the proofs later. This proof
    has found several interesting applications. However, many existing RFID
    yoking schemes are vulnerable to replay attacks. To overcome the weaknesses,
    Cho et al. proposed a new RFID yoking proof protocol and a new grouping
    protocol. Unfortunately, Cho et al.'s schemes are still vulnerable to replay
    attacks. In this paper, in addition to demonstrating weaknesses, we further
    discuss the rationale behind these weaknesses to provide a guide line for
    designing secure RFID yoking schemes. Based on the guide line, we propose a
    new RFID yoking scheme and a new RFID grouping scheme. Performance
    evaluation shows that our scheme outperforms its counterparts.
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    Efficient Clustering and Simulated Annealing Approach 
    for Circuit Partitioning
    SANDEEP Singh Gill, RAJEEVAN Chandel, ASHWANI Kumar Chandel
    Journal of shanghai Jiaotong University (Science)    2011, 16 (6): 708-712.   DOI: 10.1007/s12204-011-1138-z
    Abstract1915)            Save
    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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    Time-Varying Delay and Quantization Error
    LI Bin (李 斌), WAN Yi-ming (万一鸣), YE Hao (叶 昊)
    Journal of shanghai Jiaotong University (Science)    2011, 16 (5): 513-518.   DOI: 10.1007/s12204-011-1181-9
    Abstract1891)      PDF(pc) (303KB)(3065)       Save
    Abstract:  Problems related to fault detection of
    networked control systems (NCSs) with both uncertain time-varying
    delay and quantization error are studied in this paper. A novel
    model with the form of polytopic uncertainty is given to represent
    the influences of both the time-varying delay and the quantization
    error, and then the reference model based method is used to design
    the residual generator that is robust to both unknown
    network-induced delay and unknown inputs. A numerical example is
    also given to illustrate the merits of the presented method. The
    proposed method can be regarded as an extension of the
    authors' former work, which can only deal with time-varying delay.
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     Highly Resilient Key Distribution Strategy for Multi-level
    Heterogeneous Sensor Networks by Using Deployment Knowledge
    WANG Chih-hung (王智弘), WEI Shih-yi (魏仕益)
    Journal of shanghai Jiaotong University (Science)    2011, 16 (5): 593-599.   DOI: 10.1007/s12204-011-1194-4
    Abstract1879)            Save
    Abstract:  The most important problem in the security of wireless sensor
    network (WSN) is to distribute keys for the sensor nodes and to establish a
    secure channel in an insecure environment. Since the sensor node has limited
    resources, for instance, low battery life and low computational power, the
    key distribution scheme must be designed in an efficient manner. Recently
    many studies added a few high-level nodes into the network, called the
    heterogeneous sensor network (HSN). Most of these studies considered an
    application for two-level HSN instead of multi-level one. In this paper, we
    propose some definitions for multi-level HSN, and design a novel key
    management strategy based on the polynomial hash tree (PHT) method by using
    deployment knowledge. Our proposed strategy has lower computation and
    communication overheads but higher connectivity and resilience.
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    Investigation of Improved Approaches to Bayes Risk Decoding
    XU Hai-hua (徐海华), ZHU Jie (朱 杰)
    Journal of shanghai Jiaotong University (Science)    2011, 16 (5): 524-529.   DOI: 10.1007/s12204-011-1189-1
    Abstract1823)            Save
    Abstract:  Bayes risk (BR) decoding methods have been widely
    investigated in the speech recognition area due to its flexibility and
    complexity compared with the maximum a posteriori (MAP) method regarding to
    minimum word error (MWE) optimization. This paper investigates two improved
    approaches to the BR decoding, aiming at minimizing word error. The novelty
    of the proposed methods is shown in the explicit optimization of the
    objective function, the value of which is calculated by an improved forward
    algorithm on the lattice. However, the result of the first method is
    obtained by an expectation maximization (EM) like iteration, while the
    result of the second one is achieved by traversing the confusion network
    (CN), both of which lead to an optimized objective function value with
    distinct approaches. Experimental results indicate that the proposed methods
    result in an error reduction for lattice rescoring, compared with the
    traditional CN method for lattice rescoring.
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    Method to Calculate Resistance of High-Speed Displacement Ship Taking the Effect of Dynamic Sinkage and Trim and Fluid Viscosity into Account
    YAO Chao-bang (姚朝帮), DONG Wen-cai (董文才)
    Journal of shanghai Jiaotong University (Science)    2012, 17 (4): 421-426.   DOI: 10.1007/s12204-012-1301-1
    Abstract1810)            Save
    A method is presented to calculate the resistance of a high-speed displacement ship taking the effect of sinkage and trim and viscosity of fluid into account. A free surface flow field is evaluated by solving Reynolds averaged Navier-Stokes (RANS) equations with volume of fluid (VoF) method. The sinkage and trim are computed by equating the vertical force and pitching moment to the hydrostatic restoring force and moment. The software Fluent, Maxsurf and MATLAB are used to implement this method. With dynamic mesh being used, the position of a ship is updated by the motion of “ship plus boundary layer” grid zone. The hull factors are introduced for fast calculating the running attitude of a ship. The method has been applied to the ship model INSEAN2340 for different Froude numbers and is found to be efficient for evaluating the flow field, resistance, sinkage and trim.
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    Effect of Gr Content and Hot Extrusion on Tensile Properties of (Nano-SiCp+Gr)/Cu Composites Fabricated by Powder Metallurgy
    WANG Gui-songa,b* (王桂松), LUO Yanga (罗阳), LIU Bao-xia (刘宝玺),YIN Chenga (尹成), GENG Lina (耿林), HUANG Yu-dongb (黄玉东)
    Journal of shanghai Jiaotong University (Science)    2012, 17 (6): 658-662.   DOI: 10.1007/s12204-012-1341-6
    Abstract1805)            Save
    Novel hybrid Cu matrix composites reinforced by graphite (Gr) particle with volume fraction of 5%— 15% and nano-SiC particle (nano-SiCp) with volume fraction of 3% have been prepared by powder metallurgy. The results show that Gr and nano-SiCp distribute uniformly in the Cu matrix. With increasing the volume fraction of Gr, the tensile strength of the composites decreases from 114 to 51MPa and the elastic modulus decreases from 75 to 60GPa. Compared with the sintered composites, the tensile properties including elastic modulus, tensile strength, yield strength and tensile elongation of the hot-extruded (nano-SiCp+Gr)/Cu composites are improved greatly due to higher relative density of the composites and more uniform distribution of Gr and nano-SiCp, in addition to finer grain size of the matrix as a result of dynamic recovery and recrystallization which occur during hot extrusion process.
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    Detecting Shifted Double JPEG Compression Tampering Utilizing Both Intra-Block and Inter-Block Correlations
    ZHANG Yu-jina (张玉金), LI Sheng-honga* (李生红), WANG Shi-linb (王士林)
    Journal of shanghai Jiaotong University (Science)    2013, 18 (1): 7-16.   DOI: 10.1007/s12204-013-1362-9
    Abstract1788)            Save
    Copy-paste forgery is a very common type of forgery in JPEG images. The tampered patch has always suffered from JPEG compression twice with inconsistent block segmentation. This phenomenon in JPEG image forgeries is called the shifted double JPEG (SDJPEG) compression. Detection of SDJPEG compressed image patches can make crucial contribution to detect and locate the tampered region. However, the existing SDJPEG compression tampering detection methods cannot achieve satisfactory results especially when the tampered region is small. In this paper, an effective SDJPEG compression tampering detection method utilizing both intra-block and inter-block correlations is proposed. Statistical artifacts are left by the SDJPEG compression among the magnitudes of JPEG quantized discrete cosine transform (DCT) coefficients. Firstly, difference 2D arrays, which describe the differences between the magnitudes of neighboring JPEG quantized DCT coefficients on the intrablock and inter-block, are used to enhance the SDJPEG compression artifacts. Then, the thresholding technique is used to deal with these difference 2D arrays for reducing computational cost. After that, co-occurrence matrix is used to model these difference 2D arrays so as to take advantage of second-order statistics. All elements of these co-occurrence matrices are served as features for SDJPEG compression tampering detection. Finally, support vector machine (SVM) classifier is employed to distinguish the SDJPEG compressed image patches from the single JPEG compressed image patches using the developed feature set. Experimental results demonstrate the efficiency of the proposed method.
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    Synthesis of Sub-micrometer Lithium Iron Phosphate Particles Using Supercritical Hydrothermal Method for Lithium Ion Batteries
    LIU Xue-wu1,2*(刘学武), WEI Hao1 (魏浩), DENG Yuan-fu2 (邓远富), TANG Jie1 (汤洁), SHI Zhi-cong2 (施志聪), CHEN Guo-hua2,3 (陈国华)
    Journal of shanghai Jiaotong University (Science)    2012, 17 (5): 517-522.   DOI: 10.1007/s12204-012-1317-6
    Abstract1778)            Save
    In this study, sub-micrometer LiFePO4 particles with high purity and crystallinity were synthesized using supercritical hydrothermal method as the cathode material for lithium ion batteries. Experimental results show that templates and calcination time have significant impacts on the purity, particle size and morphology of LiFePO4 particles. The as-prepared LiFePO4 particles using polyvinyl pyrrolidone (PVP) template with additional one hour calcination at 700℃ exhibit characteristics of good crystallinity, uniform size distribution, high capacity and cycling performance. The specific discharge capacities of 141.2 and 114.0mA· h/g were obtained at the charge/discharge rates of 0.1 and 1.0 C, respectively. It retained 96.0% of an initial capacity after 100 cycles at 1.0 C rate. The good electrochemical performance of the as-synthesized material is attributed to the synergistic factors of its reasonable particle size and surface areas and high crystallinity.
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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)
    Journal of shanghai Jiaotong University (Science)    2011, 16 (6): 722-727.   DOI: 10.1007/s12204-011-1216-2
    Abstract1776)            Save
    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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    Thermal Flow Simulation of Twin-Roll Casting Magnesium Alloy
    HU Xiao-dong (胡小东), JU Dong-ying (巨东英), ZHAO Hong-yang (赵红阳)
    Journal of shanghai Jiaotong University (Science)    2012, 17 (4): 479-483.   DOI: 10.1007/s12204-012-1309-6
    Abstract1767)            Save
    In order to better understand twin-roll casting process, a 3D finite element method (FEM) simulation was carried out, based on the conditions of the pilot vertical twin-roll caster, to study the thermal flow and solidification behavior in the twin-roll casting process. The simulation results show that non-uniform temperature and velocity distribution near the side dam region are the main reason for causing non-uniform solidification and non-uniform deformation along the cast sheet width. Therefore, it is necessary to preheat the side dams or improve the design of nozzle to compensate the effect of side dams on the casting process. High quality magnesium sheets have been cast after improved the casting devices.
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    Analysis of Motion in Longitudinal Plane of Negative Buoyancy Vehicle Flying Fish II
    YAN Hui (颜 翚), GE Tong (葛 彤), YING Si-bin (应思斌), WU Chao (吴 超), YUAN Qing-qing (袁庆晴)
    Journal of shanghai Jiaotong University (Science)    2012, 17 (1): 20-024.   DOI: 10.1007/s12204-012-1225-9
    Abstract1740)            Save
    Abstract: This article describes an experimental prototype flying fish II and builds a dynamic model that is a novel type of autonomous underwater vehicle (AUV) under the condition of negative buoyancy vehicle (NBV) without large buoyancy mechanism. Compared with the AUV Remus100, the flying fish II can cruise with double speeds within the same range and dimensions. The static stability and motion modes of flying fish II in the longitudinal plane are analyzed through the linear system theory. The flying fish II has static stability in the longitudinal plane and the motion mode is related to metacentric height.
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    Photothermal Effect for Fe3O4 Nanoparticles Contained in Micelles Induced by Near-Infrared Light
    LIU Guang-zhen1,2* (刘光臻), MA Jun-ping1,2 (马俊平), LIU Jia-qiang3 (刘家强)
    Journal of shanghai Jiaotong University (Science)    2012, 17 (6): 730-733.   DOI: 10.1007/s12204-012-1354-1
    Abstract1734)            Save
    Near infrared (NIR) light induced photothermal effect for Fe3O4 nanoparticles, contained in Pluronic F127 micelles, has been studied and it exhibits high photothermal converting efficiency. Heat is found to be rapidly generated in micelles containing Fe3O4 nanoparticles by NIR laser irradiation. Upon irradiation at 808 nm light and with mass concentration of Fe3O4 nanoparticles in 4 g/L, the micelle temperature increase is higher than 34℃ for 10min irradiation. The maximum temperature of micelles containing Fe3O4 nanoparticles in 4 g/L reaches 62℃.
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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)
    Journal of shanghai Jiaotong University (Science)    2011, 16 (6): 713-721.   DOI: 10.1007/s12204-011-1215-3
    Abstract1730)            Save
     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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    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 (窦文斌), SU Hong-yan (苏宏艳)
    Journal of shanghai Jiaotong University (Science)    2011, 16 (6): 687-690.   DOI: 10.1007/s12204-011-1211-7
    Abstract1727)            Save
     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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    Directed Proxy Signature in the Standard Model
    MING Yang (明 洋), WANG Yu-min (王育民)
    Journal of shanghai Jiaotong University (Science)    2011, 16 (6): 663-671.   DOI: 10.1007/s12204-011-1208-2
    Abstract1721)            Save
     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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    Segmented Dynamic Optimization Model for Asset-Liability Management of Commercial Banks and Its Applications
    YANG Wen-ze (杨文泽), XU Xiao-ming (许晓鸣), CAI Yun-ze (蔡云泽)
    Journal of shanghai Jiaotong University (Science)    2012, 17 (1): 114-120.   DOI: 10.1007/s12204-012-1237-5
    Abstract1717)            Save
    Abstract: Asset-liability management is the core business of commercial banks. Effective method of asset-liability management is a continuously exploring topic in the academic and practical fields. According to the operational characteristics of commercial banks, this paper addresses a segmented dynamic optimization model under the perspective of the regulatory environment for China commercial banks. The model can perform segmented sliding optimization and correct control variables to make optimal decision with the changes in situations for a certain future time.
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    Ontology-Based Approach for Legal Provision Retrieval
    TANG Qi (唐琪), WANG Ying-lin* (王英林), ZHANG Ming-lu (张明禄)
    Journal of shanghai Jiaotong University (Science)    2012, 17 (2): 135-140.   DOI: 10.1007/s12204-012-1242-8
    Abstract1717)            Save
    In this paper, we present an ontology-based approach for legal provision retrieval. The approach aims at assisting the man who knows little about legal knowledge to inquire appropriate provisions. Legal ontology and legal concept probability model are main functional components in our approach. Legal ontology is extracted from Chinese laws by the natural language processing (NLP) techniques. Legal concept probability model is built from corpus, and the model is used to bridge the gap between legal ontology and natural language inquiries.
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    Studies of High-Efficiency Electrical Steels Used in Electric Vehicle Motors
    PEI Rui-lin1 (裴瑞琳), ZENG Lu-bin2 (曾鹿滨), CHEN Xiao1 (陈晓), LIU Xian-dong1 (刘献东)
    Journal of shanghai Jiaotong University (Science)    2012, 17 (3): 319-322.   DOI: 10.1007/s12204-012-1277-x
    Abstract1714)            Save
    Application of permanent magnet synchronous motor (PMSM) has been increasingly popular in electric vehicle (EV) area since cost-effective electrical steels were recently discovered. This paper mainly presents the performance and characteristics of EV motors using varieties of high-efficiency electrical steels. At first, the electro-magnetic and mechanical properties of electrical steels are described. Low loss, high induction and excellent mechanical strength are critical criteria to evaluate the electrical steel. However, the gage of electrical steel is a crucial factor to affect the properties. Secondly, the basic principle and algorithm for calculation of efficiency of an EV motor are explained. Finally, the modeling and experimental results for different gages of electrical steel sheets used in EV motors are analyzed.
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    Certificateless Strong Key-Insulated Signature Without Random Oracles
    WAN Zhong-mei (万中美), Meng Xiang-qin (孟祥芹), HONG Xuan (洪 璇)
    Journal of shanghai Jiaotong University (Science)    2011, 16 (5): 571-576.   DOI: 10.1007/s12204-011-1191-7
    Abstract1709)            Save
    Abstract:  It is important to ensure the private key secure in
    cryptosystem. To reduce the underlying danger caused by the private key
    leakage, Dodis et al. (2003) introduced the notion of key-insulated
    security. To handle the private key leakage problems in certificateless
    signature schemes, we propose a new certificateless strong key-insulated
    signature scheme. Our scheme has two desirable properties. First, its
    security can be proved without utilizing the random oracle model. Second, it
    solves the key escrow problems in identity-based key-insulated signatures (IBKISs).
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    Forming Path Optimization for Press Bending of Aluminum Alloy Aircraft Integral Panel
    YAN Yu1 (阎昱), WANG Hai-bo1* (王海波), WAN Min2 (万敏)
    Journal of shanghai Jiaotong University (Science)    2012, 17 (5): 635-642.   DOI: 10.1007/s12204-012-1336-3
    Abstract1686)            Save
    Because of the light weight, high stiffness and high structural efficiency, aluminium alloy integral panels are widely used on modern aircrafts. Press bend forming has many advantages, and it becomes a significant technique in aircraft manufacturing field. In order to design the press bend forming path for aircraft integral panels, we propose a novel optimization method which integrates the finite element method (FEM) equivalent model based on our previous study, the artificial neural network response surface, and the genetic algorithm. First, a multi-step press bend forming FEM equivalent model is established, with which the FEM experiments designed with Taguchi method are performed. Then, the backpropagation (BP) neural network response surface is developed with the sample data from the FEM experiments. Further more, genetic algorithm (GA) is applied with the neural network response surface as the objective function. Finally, experimental and simulation verifications are carried out on a single stiffener specimen. The forming error of the panel formed with the optimal path is only 5.37% and the calculating efficiency has been improved by 90.64%. Therefore, this novel optimization method is quite efficient and indispensable for the press bend forming path designing.
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