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Energy-efficient and security-optimized AES hardware design for ubiquitous computing

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Journal of Systems Engineering and Electronics 2008年第4期19卷 652-658页

作者： Chen Yicheng Zou Xuecheng Liu Zhenglin Han Yu Zheng Zhaoxia Dept. of Electronic Science and Technology Huazhong Univ. of Science and Technology Wuhan 430074 P. R. China

Ubiquitous computing must incorporate a certain level of security. For the severely resource constrained applications, the energy-efficient and small size cryptography algorithm implementation is a critical problem. Hardware implementations of the advanced encryption standard （AES） for authentication and encryption are presented. An energy consumption variable is derived to evaluate low-power design strategies for battery-powered devices. It proves that compact AES architectures fail to optimize the AES hardware energy, whereas reducing invalid switching activities and implementing power-optimized sub-modules are the reasonable methods. Implementations of different substitution box （S-Boxes） structures are presented with 0.25μm 1.8 V CMOS （complementary metal oxide semiconductor） standard cell library. The comparisons and trade-offs among area, security, and power are explored. The experimental results show that Galois field composite S-Boxes have smaller size and highest security but consume considerably more power, whereas decoder-switch-encoder S-Boxes have the best power characteristics with disadvantages in terms of size and security. The combination of these two type S-Boxes instead of homogeneous S-Boxes in AES circuit will lead to optimal schemes. The technique of latch-dividing data path is analyzed, and the quantitative simulation results demonstrate that this approach diminishes the glitches effectively at a very low hardware cost.

关键词： encryption and decryption power analysis model inhomogeneous S-Boxes ubiquitous computing advanced encryption standard.

Surfactant-Enhanced Phytoremediation of Soils Contaminated with Hydrophobic Organic Contaminants:Potential and Assessment

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Pedosphere 2007年第4期17卷 409-418页

作者： GAO Yan-Zheng LING Wan-Ting ZHU Li-Zhong ZHAO Bao-Wei ZHENG Qing-Song College of Resource and Environmental Sciences Nanjing Agricultural University Nanjing 210095 College of Environmental and Resource Sciences Zhejiang University Hangzhou 310028 （China） School of Environmental and Municipal Engineering Lanzhou Jiaotong University Lanzhou 730070 （China）

Phytoremediation is becoming a cost-effective technology for the in-situ clean up of sites polluted with hydrophobic organic contaminants （HOCs）. The major factors limiting phytoremediation are the mass transfer, rate of plant uptake, and microbial biodegradation of HOCs. This article discusses the potential of surfactants to enhance desorption, plant uptake, and biodegradation of HOCs in the contaminated sites. Positive effects of surfactants on phytoremediation have been recently observed in greenhouse studies. The presence of some nonionic surfactants including polyoxyethylene sorbltan monooleate （Tween 80） and polyoxyethylene（23）dodecanol （Brij35） at relatively low concentrations resulted in significant positive effects on phytoremediation for pyrene-contaminated soil. However, the anionic surfactant （sodium dodecyl sulfate, SDS） and the cationic surfactant （cetyltrimethylammonium bromide, CTMAB） were not useful because of their phytotoxicity or low efficiency for surfactant-enhanced phytoremediation （SEPR）. The mechanisms of SEPR for HOC-contaminated sites were evaluated by considering experimental observations. In view of concerns about the cost effectiveness and toxicity of surfactants to plants, more research is needed to enhance the use of SEPR technology.

关键词： hydrophobic organic contaminant remediation SEPR soil surfaztant

A secure and high-performance multi-controller architecture for software-defined networking

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Frontiers of Information Technology & Electronic Engineering 2016年第7期17卷 634-646页

作者： Huan-zhao WANG Peng ZHANG Lei XIONG Xin LIU Cheng-chen HU Department of Computer Science and Technology Xi'an Jiaotong UniversityXi'an 710059China Science and Technology on Information Transmission and Dissemination in Communication Networks Laboratory Shijiazhuang 050081China MOE Key Laboratory for Intelligent Networks and Network Security Xi'an Jiaotong UniversityXi'an 710049China

Controllers play a critical role in software-defined networking(SDN).However,existing singlecontroller SDN architectures are vulnerable to single-point failures,where a controller's capacity can be saturated by flooded flow *** addition,due to the complicated interactions between applications and controllers,the flow setup latency is relatively *** address the above security and performance issues of current SDN controllers,we propose distributed rule store(DRS),a new multi-controller architecture for *** DRS,the controller caches the flow rules calculated by applications,and distributes these rules to multiple controller *** controller instance holds only a subset of all rules,and periodically checks the consistency of flow rules with each *** from switches are distributed among multiple controllers,in order to mitigate controller capacity saturation *** the same time,when rules at one controller are maliciously modified,they can be detected and recovered in *** implement DRS based on Floodlight and evaluate it with extensive *** results show that DRS can effectively maintain a consistently distributed rule store,and at the same time can achieve a shorter flow setup time and a higher processing throughput,compared with ONOS and Floodlight.

关键词： Software-defined networking(SDN) Security Multi-controller Distributed rule store

Preparation of Well-shaped Microcapsule Immobilizing Inorganic Nanoparticles

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Chinese Journal of Chemical Engineering 2008年第3期16卷 384-388页

作者：刘正平裴丽霞纪红兵姚兴东 The Key Laboratory of Enhanced Heat Transfer and Energy Conservation Ministry of Education School of Chemistry and Chemical Engineering South China University of Technology Guangzhou 510640 China Shanghai Key Laboratory of Green Chemistry and Chemical Processes Department of Chemistry East China Normal University Shanghai 200062 China College of Chemistry ＆ Ecological Engineering Guangxi University for Nationalities Nanning 530006 China

A facile and efficient method has been developed for microencapsulation of metal oxide nanoparticles in polyurea via interfacial polymerization of toluene-2,4-diisocyanate and H20 through the atomizing emulsification approach. The resultant microcapsules were well-shaped and uniform sphere with diameter ranging from 2 to 6 um. Thermogravimetry （TG） and differential scanning calorimetry （DSC） curves revealed that the microcapsules showed good thermal stability （no decomposition observed under 245℃）. Besides, the microencapsulated TiC2 has been used as an efficient catalyst for photocatalytic degradation of methyl orange. Furthermore, the photocatalysis of immobilized TiC2 could be enhanced by introducing UV absorbing agent to the wall of microcapsules.

关键词： encapsulation titanium dioxide microcapsule interfacial polymerization

Thermal Magnifier and Minifier

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Communications in Theoretical Physics 2016年第3期65卷 375-380页

作者：沈翔瀛陈祎璇黄吉平 Department of Physics State Key Laboratory of Surface PhysicsKey Laboratory of Micro and Nano Photonic Structures(Ministry of Education)and Collaborative Innovation Center of Advanced MicrostructuresFudan University

For thermal conduction cases,one can detect the size of an object explicitly by measuring the temperature distribution around *** the temperature is the only signature we can obtain,we will give an incorrect judgment on the shape or size of the object by disturbing the distribution of *** to this principle,in this article,we develop a transformation method and design a dual-functional thermal device,which can create a thermal illusion that the object inside it ＂seems＂ to appear bigger or smaller than its original *** device can functionally switch among magnifier and miniGer at will The proposed device consists of two layers：the cloak and the complementary material.A thermal cloak can make the internal region thermally ＂invisible＂ while the complementary layer offsets this *** combination leads to the illusion of magnification and *** a result of finite element simulations,the performances of the illusions are confirmed.

关键词： transformation thermotics thermal metamaterial thermal illusion complemenetuary laser

Nanoscratch behaviors of La_(0.7)Sr_(0.3)MnO_(3+δ) thin films

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Journal of Rare Earths 2008年第6期26卷 809-812页

作者：江少群马欣新唐光泽孙明仁王刚 School of Materials Science and Engineering Harbin Institute of Technology

The nanoscratch behaviors of La0.7Sr0.3MnO3＋δ films, which were deposited with ratio of O2/（O2＋Ar）, ranging from 4.4% to 45.6% by DC magnetron sputter, were investigated by a nanoindentation technique. The results indicated that the friction coefficient between the films and the diamond tip depended on the loading critical load. The friction coefficient was about 0.08-0.12 when the loading normal load was less than the loading critical load. The films displayed excellent elastic recovery after unloading. When the loading load was larger than the loading critical load, plastic deformation and ploughing appeared for the films. The friction coefficient was about 0.43 when the film was damaged completely. The suitable decrease in ratio of O2/（O2＋Ar） could improve the nanoscratch resistance of the films. The film deposited with O2/（O2＋Ar）=25% possessed better scratch resistance due to good elastic recovery, high nanohardness, and critical load. The loading critical load of the film was larger than 80 raN.

关键词： La1-xSrxMnO3 magnetic recording scratch testing nanoindentation hardness rare earths

Four-step DOAS calibration method of SO_2 in flue gas

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Chinese Optics Letters 2009年第6期7卷 539-541页

作者：周涛刘斌孙长库 State Key Laboratory of Precision Measurement Technology and Instruments Tianjin University

SO2 monitoring in the flue gas of a coal burning boiler is important for environmental protection. The non- linearity of practical condition causes deviation from theoretical law. On the basis of the Lambert-Beer Law, a new four-step calibrntion method is introduced. This method includes cross section interpola- tion, weighting spectral region combination, acquiring the spectrum with new calibration devices, and least-square fitting. Compared with conventional methods, this new method is low cost, convenient, and accurate. In the proof test, SO2 samples with different concentrations are measured. The average errors are less than 1.5%, while the maximum deviation is less than 4.5%.

关键词： Beverages Calibration Flue gases

Closed-loop dynamic control allocation for aircraft with multiple actuators

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Chinese Journal of Aeronautics 2013年第3期26卷 676-686页

作者： Gai Wendong Wang Honglun Science and Technology on Aircraft Control Laboratory Beihang University

A closed-loop control allocation method is proposed for a class of aircraft with multiple actuators. Nonlinear dynamic inversion is used to design the baseline attitude controller and derive the desired moment increment. And a feedback loop for the moment increment produced by the deflections of actuators is added to the angular rate loop, then the error between the desired and actual moment increment is the input of the dynamic control allocation. Subsequently, the stability of the closed-loop dynamic control allocation system is analyzed in detail. Especially, the closedloop system stability is also analyzed in the presence of two types of actuator failures： loss of effectiveness and lock-in-place actuator failures, where a fault detection subsystem to identify the actuator failures is absent. Finally, the proposed method is applied to a canard rotor/wing （CRW） aircraft model in fixed-wing mode, which has multiple actuators for flight control. The nonlinear simulation demonstrates that this method can guarantee the stability and tracking performance whether the actuators are healthy or fail.

关键词： Canard rotor/wing aircraft Closed-loop control allocation Dynamic inversion Flight control systems Redundant actuators

Research of Compound Controller for Flight Simulator with Disturbance Observer

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Chinese Journal of Aeronautics 2011年第5期24卷 613-621页

作者： WU Yunjie LIU Xiaodong TIAN Dapeng Science and Technology on Aircraft Control Laboratory School of Automation Science and Electrical Engineering Beihang University Beijing 100191 China

A compound controller is proposed to alleviate the considerable chattering in output of zero phase error tracking controller （ZPETC）, when the flight simulator losses command data of simulation signal. Besides, the shortcomings, caused by conventional differential methods in retrieving velocity and acceleration signals, are avoided to a certain extent. The compound controller based on disturbance observer （DOB） is composed of a feed-forward controller and a feedback controller. It estimates velocity and acceleration of unknown tracking signal, and also velocity response with an approximate method for differential. The experiments on a single-axis flight simulator show that the proposed method has strong robustness against parameter perturbations and external disturbances, owing to the introduced DOB. Compared with the scheme with ZPETC, the proposed scheme possesses more simple design and better tracking performance. Moreover, it is less sensitive to position command distortion of flight simulator.

关键词： compound controller zero phase error tracking controller flight simulators disturbance observer robustness