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Science China(Information Sciences) 2017年第4期60卷 60-70页

作者： weidong fang Wuxiong ZHANG Yang YANG Yang LIU Wei CHEN Key Laboratory of Wireless Sensor Network & Communication Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai Research Center for Wireless Communication School of Computer Science and Technology China University of Mining and Technology

Compared with the encryption and the authentication which can prevent the external attacks,the trust management schemes are the better approaches for defending against the internal attacks in wireless sensor network(WSN). The reputation time-varying(RTV) attacks are internal attacks. In the reputation timevarying attacks, the reputation value of nodes is manipulated to adjust dynamically by the compromised nodes or malicious attackers. Hence, these attacks have greater covert and invasive. In this paper, we propose a Timewindow-based Resilient Trust Management Scheme(TRTMS) to defend against the reputation time-varying attacks in wireless sensor network. In this scheme, based on BETA distribution, the behaviors of compromised nodes are analyzed for a period of time, and then the difference judgment and the trend analysis are utilized to identify the abnormality of nodes’ reputation value, meanwhile, the control factor Fc and the time window are introduced to verify and remove the compromised modes from the suspected malicious nodes, which refer to those nodes’ reputation value changes are caused by the wireless channel changes. The result of simulation shows that our proposed scheme can defend reputation time-varying attacks effectively and it is convenient to implement.

关键词： wireless sensor network(WSN) reputation time-varying attack trust value trust management time window

Energy Efficiency in Internet of Things:An Overview

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Computers, Materials & Continua 2020年第5期63卷 787-811页

作者： Wuxiong Zhang weidong fang Qianqian Zhao Xiaohong Ji Guoqing Jia Key Laboratory of Wireless Sensor Network&Communication Shanghai Institute of Micro-System and Information TechnologyChinese Academy of SciencesShanghai201899China Shanghai Research Center for Wireless Communication Shanghai201210China College of Physics and Electronic Information Engineering Qinghai University for NationalitiesXining810007China

Energy efficiency is very important for the Internet of Things(IoT),especially for front-end sensed terminal or node.It not only embodies the node’s life,but also reflects the lifetime of the network.Meanwhile,it is also a key indicator of green communications.Unfortunately,there is no article on systematic analysis and review for energy efficiency evaluation in IoT.In this paper,we systemically analyze the architecture of IoT,and point out its energy distribution,Furthermore,we summarized the energy consumption model in IoT,analyzed the pros and cons of improving energy efficiency,presented a state of the art the evaluation metrics of energy efficiency.Finally,we conclude the techniques and methods,and carry out a few open research issues and directions in this field.

关键词： Internet of things wireless sensor network energy efficiency energy consumption model

Trust management-based and energy efficient hierarchical routing protocol in wireless sensor networks

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Digital Communications and Networks 2021年第4期7卷 470-478页

作者： weidong fang Wuxiong Zhang Wei Yang Zhannan Li Weiwei Gao Yinxuan Yang Science and Technology on Micro-system Laboratony Shanghai Institute of Micro-system and Informnation TechnologyChinese Academy of SciencesShanghai201899PR China University of Chinese Academy of Sciences Beijing100049PR China State Kg Laboramry of Networking and Switehing Technology Beijing University of Posts and TelecommunicationsBeijing 100876PR China Guangdong Southern Planning&Designing Institute of Telecom Consultation Co. Ltd.Shenzhen518038PR China Department of Information and Communication Engineering Harbin Engineering UniversityHarbin150001PR China Fuzhou Internet of Things Open Lab Co. LtdFuzhou350015PR China Shanghai Research and Development Center for Micro-Nano Electronics Shanghai 201210P.R.China

The single planar routing protocol has a slow convergence rate in the large-scale Wireless Sensor Network(WSN).Although the hierarchical routing protocol can effectively cope with large-scale application scenarios,how to elect a secure cluster head and balance the network load becomes an enormous challenge.In this paper,a Trust Management-based and Low Energy Adaptive Clustering Hierarchy protocol(LEACH-TM)is proposed.In LEACH-TM,by using the number of dynamic decision cluster head nodes,residual energy and density of neighbor nodes,the size of the cluster can be better constrained to improve energy efficiency,and avoid excessive energy consumption of a node.Simultaneously,the trust management scheme is introduced into LEACH-TM to defend against internal attacks.The simulation results show that,compared with LEACH-SWDN protocol and LEACH protocol,LEACH-TM outperforms in prolonging the network lifetime and balancing the energy consumption,and can effectively mitigate the influence of malicious nodes on cluster head selection,which can greatiy guarantee the security of the overall network.

关键词： Internet of things Wireless sensor network Secure routing protocol Trust management

Comprehensive Analysis of Secure Data Aggregation Scheme for Industrial Wireless Sensor Network

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Computers, Materials & Continua 2019年第8期61卷 583-599页

作者： weidong fang Wuxiong Zhang QianQian Zhao Xiaohong Ji Wei Chen Biruk Assefa Key Laboratory of Wireless Sensor Network&Communication Shanghai Institute of Micro-system and Information TechnologyChinese Academy of SciencesShanghai201899China Shanghai Research Center for Wireless Communication Shanghai201210China College of Physics and Electronic Information Engineering Qinghai University for NationalitiesXining810007China School of Computer Science and Technology China University of Mining and TechnologyXuzhou221116China Infromation Communication Technology Department Wollo UniversityDessie EthiopiaEthiopia

As an Industrial Wireless Sensor Network(IWSN)is usually deployed in a harsh or unattended environment,the privacy security of data aggregation is facing more and more challenges.Currently,the data aggregation protocols mainly focus on improving the efficiency of data transmitting and aggregating,alternately,the aim at enhancing the security of data.The performances of the secure data aggregation protocols are the trade-off of several metrics,which involves the transmission/fusion,the energy efficiency and the security in Wireless Sensor Network(WSN).Unfortunately,there is no paper in systematic analysis about the performance of the secure data aggregation protocols whether in IWSN or in WSN.In consideration of IWSN,we firstly review the security requirements and techniques in WSN data aggregation in this paper.Then,we give a holistic overview of the classical secure data aggregation protocols,which are divided into three categories:hop-by-hop encrypted data aggregation,end-to-end encrypted data aggregation and unencrypted secure data aggregation.Along this way,combining with the characteristics of industrial applications,we analyze the pros and cons of the existing security schemes in each category qualitatively,and realize that the security and the energy efficiency are suitable for IWSN.Finally,we make the conclusion about the techniques and approach in these categories,and highlight the future research directions of privacy preserving data aggregation in IWSN.

关键词： Industrial wireless sensor network wireless sensor network cyber security secure data aggregation protocol

Fire Detection Method Based on Improved Fruit Fly Optimization-Based SVM

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Computers, Materials & Continua 2020年第1期62卷 199-216页

作者： fangming Bi Xuanyi Fu Wei Chen weidong fang Xuzhi Miao Biruk Assefa College of Computer Science and Technology China University of Mining and TechnologyXuzhou221116China College of Computer Science and Technology Mine Digitization Engineering Research Center of the Ministry of EducationChina University of Mining and TechnologyXuzhou221116China College of Computer Science and Technology Xi’an University of Science and TechnologyXi’an710054China Key Laboratory of Wireless Sensor Network&Communication Shanghai Institute of Micro-System and Information TechnologyChinese Academy of SciencesShanghai201899China Infromation Communication Technology Department Wollo UniversityDessie EthiopiaP.o Box 1145Ethiopia

Aiming at the defects of the traditional fire detection methods,which are caused by false positives and false negatives in large space buildings,a fire identification detection method based on video images is proposed.The algorithm first uses the hybrid Gaussian background modeling method and the RGB color model to perform fire prejudgment on the video image,which can eliminate most non-fire interferences.Secondly,the traditional regional growth algorithm is improved and the fire image segmentation effect is effectively improved.Then,based on the segmented image,the dynamic and static features of the fire flame are further analyzed and extracted in the area of the suspected fire flame.Finally,the dynamic features of the extracted fire flame images were fused and classified by improved fruit fly optimization support vector machine,and the recognition results were obtained.The video-based fire detection method proposed in this paper greatly improves the accuracy of fire detection and is suitable for fire detection and identification in large space scenarios.

关键词： Fire detection image segmentation feature extraction fruit fly optimization support vector machine

Design of a large-range rotary microgripper with freeform geometries using a genetic algorithm

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Microsystems & Nanoengineering 2022年第1期8卷 59-72页

作者： Chen Wang Yuan Wang weidong fang Xiaoxiao Song Aojie Quan Michiel Gidts Hemin Zhang Huafeng Liu Jian Bai Sina Sadeghpour Michael Kraft College of Optical Science and Engineering Zhejiang UniversityHangzhouChina Department of Electrical Engineering and Computer Science University of LiegeLiegeBelgium ESAT-MNS University of LeuvenLeuvenBelgium PGMF and School of Physics Huazhong University of Science and TechnologyWuhanChina

This paper describes a novel electrostatically actuated microgripper with freeform geometries designed by a genetic algorithm.This new semiautomated design methodology is capable of designing near-optimal MEMS devices that are robust to fabrication tolerances.The use of freeform geometries designed by a genetic algorithm significantly improves the performance of the microgripper.An experiment shows that the designed microgripper has a large displacement(91.5μm)with a low actuation voltage(47.5 V),which agrees well with the theory.The microgripper has a large actuation displacement and can handle micro-objects with a size from 10 to 100μm.A grasping experiment on human hair with a diameter of 77μm was performed to prove the functionality of the gripper.The result confirmed the superior performance of the new design methodology enabling freeform geometries.This design method can also be extended to the design of many other MEMS devices.

关键词： handle algorithm. algorithm

Design of freeform geometries in a MEMS accelerometer with a mechanical motion preamplifier based on a genetic algorithm

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Microsystems & Nanoengineering 2020年第1期6卷 122-135页

作者： Chen Wang Xiaoxiao Song weidong fang fang Chen Ioannis Zeimpekis Yuan Wang Aojie Quan Jian Bai Huafeng Liu Gerold Schropfer Chris Welham Michael Kraft College of Optical Science and Engineering Zhejiang UniversityHangzhou 310027P.R.China Department of Electrical Engineering and Computer Science University of LiegeLiege B-4000Belgium ESAT-MICAS University of LeuvenLeuven 3001Belgium PGMF and School of Physics Huazhong University of Science and TechnologyWuhan 430074P.R.China Shanghai Institute of Microsystem and Information Technology Chinese Academy of SciencesShanghai 200050P.R.China ORC University of SouthamptonSouthampton SO171BJUK Coventor—A Lam Research Company Villebon sur Yvette 91140France

This paper describes a novel,semiautomated design methodology based on a genetic algorithm(GA)using freeform geometries for microelectromechanical systems(MEMS)devices.The proposed method can design MEMS devices comprising freeform geometries and optimize such MEMS devices to provide high sensitivity,large bandwidth,and large fabrication tolerances.The proposed method does not require much computation time or memory.The use of freeform geometries allows more degrees of freedom in the design process,improving the diversity and performance of MEMS devices.A MEMS accelerometer comprising a mechanical motion amplifier is presented to demonstrate the effectiveness of the design approach.Experimental results show an improvement in the product of sensitivity and bandwidth by 100%and a sensitivity improvement by 141%compared to the case of a device designed with conventional orthogonal shapes.Furthermore,excellent immunities to fabrication tolerance and parameter mismatch are achieved.

关键词： accelerometer algorithm motion

Image formation of brain function in patients suffering from knee osteoarthritis treated with moxibustion

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Journal of Traditional Chinese Medicine 2013年第2期33卷 181-186页

作者： Hongwu Xie fangming Xu Rixin Chen Tianyou Luo Mingren Chen weidong fang Fajin Lü Fei Wu Yune Song Jun Xiong Department of Recovery with Acupuncture Hospital Affiliated to Jiangxi College of Traditional Chinese MedicineNanchang 330006China College of Traditional Chinese Medicine Chongqing Medical University Department of Radiology the First Hospital Affiliated to Chongqing Medical University

OBJECTIVES:Functional magnetic resonance imaging(fMRI) technology was used to study changes to the resting state blood flow in the brains of patients with knee osteoarthritis(KOA) before and after treatment with moxibustion at the acupoint of the left Dubi(ST 35) and to probe the cerebral mechanism underlying the effect of moxibustion.METHODS:The resting state brain function of 30 patients with left KOA was scanned with fMRI before and after treatment with moxibustion.The analytic methods of fractional amplitude of low frequency fluctuation(fALFF) and regional homogeneity(ReHo) were used to observe changes in resting state brain function.RESULTS:The fALFF values of the right cerebrum,extra-nucleus,left cerebellum,left cerebrum and white matter of patients after moxibustion treatment were higher than before treatment,and the fALFF values of the precentral gyrus,frontal lobe and occipital lobe were lower than before treatment(P<0.05,K≥85).The ReHo values of the thalamus,extra-nucleus and parietal lobe of patients were much higher than those before moxibustion treatment,and the ReHo values of the right cerebrum,left cerebrum and frontal lobe were lower than before treatment(P<0.05,K≥85).CONCLUSION:The influence of moxibustion on obvious changes in brain regions basically conforms to the way that pain and warmth is transmitted in the body,and the activation of sensitive systems in the body may be objective evidence of channel transmission.The regulation of brain function by moxibustion is not in a single brain region but rather in a network of many brain regions.

关键词：大脑功能骨性关节炎治疗患者艾灸磁共振成像技术膝关节图像

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Diagnostic value of fluid attenuated inversion recovery versus T_2-weighted image in diffuse axonal injury

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Neural Regeneration Research 2008年第8期3卷 890-893页

作者： Haijian Xia Xiaochuan Sun Wenyuan Tang Tianyou Luo Fajin Lu weidong fang Luping Zheng Department of Neurosurgery First Affiliated Hospital of Chongqing Medical University Chongqing 400016 China Department of Radiology First Affiliated Hospital of Chongqing Medical University Chongqing 400016 China

BACKGROUND：At present, the most common examination modality for diffuse axonal injury （DAI） is CT or MRI. However, both methods exhibit low sensitivity in the diagnosis of DAI lesions. OBJECTIVE： To investigate the value of fluid attenuated inversion recovery （FLAIR） in the clinical diagnosis of DAI, and to compare with T2-weighted images. DESIGN, TIME AND SETTING： This prospective study was based on imaging analysis, and was performed in the First Affiliated Hospital of Chongqing Medical University （Chongqing, China） between October 2002 and April 2004. PARTICIPANTS： Sixty-three patients with craniocerebral injury were admitted to the Department of Neurosurgery at the First Affiliated Hospital of Chongqing Medical University, including 50 males and 13 females. The patients were included in the experiment and were divided into DAI （n=24） and non-DAI （n=39） groups, according to the emergent CT findings and clinical manifestations. METHODS： Both groups underwent MR examinations, including axial and sagittal T1 weighted images （TR = 450 ms, TE = 8-9 ms）, T2-weighted images （TR = 3 600 ms, TE = 100 ms）, and FLAIR （TR = 10 000 ms, TI = 2 500 ms, TE = 40 ms）, 8-mm thick and 2-mm wide, using a GE Sigma MRI device. MAIN OUTCOME MEASURES： The DAI diagnostic rate and lesion-detecting rate of T2-weighted images and FLAIR were determined. RESULTS： All 63 patients were included in the final analysis. The DAI diagnosis rates of FLAIR and T2-weighted images were 88% （21/24） and 62% （15/24）, respectively, of which the difference was statistically significant （P 〈 0.05）. T2-weighted images and FLAIR detected lesions located in the gray matter-white matter junction in parasagittal areas, the corpus callosum, deep periventricular white matter, basal ganglia, internal capsule, hippocampus, cerebellum, and brain stem, with a detailed amount of 123 and 256, respectively. FLAIR was significantly greater than T2-weighted images （P 〈 0.01）. CONCLUSION： FLAIR is superior to T2-weighted images for improving the DAI diagnostic rate and lesi

关键词： diffuse axonal injury magnetic resonance imaging tomography, X-ray computed

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Evaluation of non-typical diffuse axonal injury by magnetic resonance techniques

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Neural Regeneration Research 2010年第17期5卷 1337-1341页

作者： Haijian Xia Xiaochuan Sun Zongduo Guo weidong fang Fajin Lü Haitao Wu Tianyou Luo Wenyuan Tang Department of Neurosurgery First Affiliated Hospital of Chongqing Medical UniversityChongqing 400016China Department of Radiology First Affiliated Hospital of Chongqing Medical UniversityChongqing 400016China

Because diffuse axonal injury（DAI）lacks specific clinical manifestations,it is difficult to evaluate DAI using computer tomography or conventional magnetic resonance imaging（MRI）.This study investigated the value of magnetic resonance techniques using fluid-attenuated inversion recovery（FLAIR）and proton magnetic resonance spectroscopy（1HMRS）for diagnosing DAI.The corpus callosum and basal nuclei were analyzed using morphological and functional imaging.Similar to the DAI group,the non-typical DAI group exhibited similar lesion characteristics on FLAIR,as well as post-injury neurochemical and molecular changes in the corpus callosum,as detected by 1HMRS.However,there were differences in degree and severity of injury.Compared to conventional MRI,FLAIR significantly increased lesion detection.1HMRS determined biochemical metabolism changes in midline structures following DAI,which resulted in increased diagnosis of non-typical DAI,which displayed similar lesion distribution,morphology,and function as DAI.Thus,the experiment proved the value of FLAIR and 1HMRS in non-typical DAI.

关键词： diffuse axonal injury magnetic resonance imaging magnetic resonance spectroscopy case-control study traumatic brain injury

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