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Journal of Computational Mathematics 2023年第5期41卷 797-816页

作者： Yayun Fu Wenjun cai Yushun Wang School of Science Xuchang UniversityXuchang 461000China Jiangsu Key Laboratory for NSLSCS Jiangsu Collaborative Innovation Center of Biomedial Functional MaterialsSchool of Mathematical SciencesNanjing Normal UniversityNanjing 210023China

The main objective of this paper is to present an efficient structure-preserving scheme,which is based on the idea of the scalar auxiliary variable approach,for solving the twodimensional space-fractional nonlinear Schrodinger ***,we reformulate the equation as an canonical Hamiltonian system,and obtain a new equivalent system via introducing a scalar ***,we construct a semi-discrete energy-preserving scheme by using the Fourier pseudo-spectral method to discretize the equivalent system in space *** that,applying the Crank-Nicolson method on the temporal direction gives a linearly-implicit scheme in the fully-discrete *** expected,the proposed scheme can preserve the energy exactly and more efficient in the sense that only decoupled equations with constant coefficients need to be solved at each time ***,numerical experiments are provided to demonstrate the efficiency and conservation of the scheme.

关键词： Fractional nonlinear Schrodinger equation Hamiltonian system Scalar auxiliary variable approach Structure-preserving algorithm

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基于形式化方法的区块链系统漏洞检测模型

软件学报 2024年第9期35卷 4193-4217页

作者：陈锦富冯乔伟蔡赛华施登洲 Rexford Nii Ayitey SOSU 江苏大学计算机科学与通信工程学院江苏镇江212013 江苏省工业网络安全技术重点实验室(江苏大学) 江苏镇江212013 Faculty of Computing and Information Systems Ghana Communication Technology UniversityAccra 23321Ghana

随着区块链技术在各行各业的广泛应用,区块链系统的架构变得越来越复杂,这也增加了安全问题的数量.目前,在区块链系统中采用了模糊测试、符号执行等传统的漏洞检测方法,但这些技术无法有效检测出未知的漏洞.为了提高区块链系统的安全性... 详细信息

随着区块链技术在各行各业的广泛应用,区块链系统的架构变得越来越复杂,这也增加了安全问题的数量.目前,在区块链系统中采用了模糊测试、符号执行等传统的漏洞检测方法,但这些技术无法有效检测出未知的漏洞.为了提高区块链系统的安全性,提出基于形式化方法的区块链系统漏洞检测模型VDMBS(vulnerability detection model for blockchain systems),所提模型综合系统迁移状态、安全规约和节点间信任关系等多种安全因素,同时提供基于业务流程执行语言BPEL(business process execution language)的漏洞模型构建方法.最后,用NuSMV在基于区块链的电子投票选举系统上验证所提出的漏洞检测模型的有效性,实验结果表明,与现有的5种形式化测试工具相比,所提出的VDMBS模型能够检测出更多的区块链系统业务逻辑漏洞和智能合约漏洞.

关键词：区块链系统安全因素漏洞检测模型形式化验证 BPEL流程

LLMP： Exploiting LLDP for Latency Measurement in Software-Defined Data Center Networks

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Journal of Computer Science & Technology 2018年第2期33卷 277-285页

作者： Yang Li Zhi-Ping cai Hong Xu College of Computer National University of Defense Technology Changsha 410073 China Department of Computer Science City University of Hong Kong Hong Kong 9990V7 China

The administrators of data center networks have to continually monitor path latency to detect network anomaly quickly and ensure the efficient operation of the networks. In this work, we propose Link Layer Measurement Protocol （LLMP）, a prototype latency measuring framework based on the Link Layer Discovery Protocol （LLDP）. LLDP is utilized by the controller to discover network topology dynamically. We insert timestamps into the optional LLDPTLV field in LLDP, so that the controller can estimate latency on any single link. The framework utilizes a reactive measurement approach without injecting any probe packets to the network. Our experiments show that the latency of a link can be measured accurately by LLMP. In relatively complex network conditions, LLMP can still maintain a high accuracy. We store the LLMP measurement results into a latency matrix, which can be used to infer the path latency.

关键词： software-defined network (SDN) Link Layer Discovery Protocol (LLDP) latency measurement

育龄期PCOS患者血清TSH水平与性激素的相关性研究

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中国血液流变学杂志 2024年第1期34卷 141-145,167页

作者：蔡婧珊郑东杨倩苏州大学附属第一医院临床检测中心江苏苏州215006

目的探讨甲状腺功能正常的育龄期多囊卵巢综合征(PCOS)患者促甲状腺激素(TSH)水平对性激素的影响及其相关性。方法选取2019年12月—2023年5月于苏州大学附属第一医院就诊的151例甲状腺功能正常的育龄期PCOS患者作为研究对象,以TSH水平... 详细信息

目的探讨甲状腺功能正常的育龄期多囊卵巢综合征(PCOS)患者促甲状腺激素(TSH)水平对性激素的影响及其相关性。方法选取2019年12月—2023年5月于苏州大学附属第一医院就诊的151例甲状腺功能正常的育龄期PCOS患者作为研究对象,以TSH水平二等分组,对两组患者血清甲状腺激素指标[TSH、游离三碘甲状腺原氨酸(FT3)、游离甲状腺素(FT4)]及性激素指标[卵泡刺激素(FSH)、黄体生成素(LH)、睾酮(T)、泌乳素(PRL)、孕酮(Pg)、雌二醇(E2)和脱氢表雄酮硫酸酯(DHEAS)]水平进行分析;再根据BMI将PCOS患者分为正常BMI组(n=91)和高BMI组(n=60),比较两组患者血清甲状腺激素及性激素水平。结果①TSH低值组与TSH高值组血清甲状腺激素和性激素指标水平差异无统计学意义(P>0.05);Pearson相关性分析结果显示,TSH与PRL呈正相关性(P0.05);②高BMI组FT4和FSH水平低于正常BMI组,TSH、T和Pg水平高于正常BMI组,差异有统计学意义(P0.05);Pearson相关性分析结果显示,两组血清TSH与LH/FSH,T及Pg无显著相关性(P>0.05);③无论是正常BMI还是高BMI的PCOS患者,正常范围内的TSH水平高低不影响FT3、FT4及性激素指标水平(P>0.05)。结论正常范围内的TSH水平与性激素水平无关。即使性激素水平在正常范围内,育龄期PCOS患者应常规筛查血清TSH及其他甲状腺激素水平,及时发现可能存在的甲状腺功能异常并及时进行相应干预,降低对生殖和内分泌紊乱的影响。

关键词：多囊卵巢综合征促甲状腺激素性激素身体质量指数

Modal parameter identification of flexible spacecraft using the covariance-driven stochastic subspace identification(SSI-COV) method

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Acta Mechanica Sinica 2016年第4期32卷 710-719页

作者： Yong Xie Pan Liu Guo-Ping cai Department of Engineering Mechanics State Key Laboratory of Ocean Engineering Shanghai Jiao Tong University

In this paper, the on-orbit identification of modal parameters for a spacecraft is investigated. Firstly, the coupled dynamic equation of the system is established with the Lagrange method and the stochastic state-space model of the system is obtained. Then, the covariance-driven stochastic subspace identification（SSI-COV） algorithm is adopted to identify the modal parameters of the system. In this algorithm, it just needs the covariance of output data of the system under ambient excitation to construct a Toeplitz matrix, thus the system matrices are obtained by the singular value decomposition on the Toeplitz matrix and the modal parameters of the system can be found from the system matrices. Finally,numerical simulations are carried out to demonstrate the validity of the SSI-COV algorithm. Simulation results indicate that the SSI-COV algorithm is effective in identifying the modal parameters of the spacecraft only using the output data of the system under ambient excitation.

关键词： covariance stochastic subspace spacecraft modal validity matrices identifying excitation Toeplitz

Face anti-spoofing algorithm combined with CNN and brightness equalization

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Journal of Central South University 2021年第1期28卷 194-204页

作者： cai Pei QUAN Hui-min College of Electrical and Information Engineering Hunan UniversityChangsha 410082China

Face anti-spoofing is a relatively important part of the face recognition system,which has great significance for financial payment and access control *** at the problems of unstable face alignment,complex lighting,and complex structure of face anti-spoofing detection network,a novel method is presented using a combination of convolutional neural network and brightness ***,multi-task convolutional neural network(MTCNN)based on the cascade of three convolutional neural networks(CNNs),P-net,R-net,and O-net are used to achieve accurate positioning of the face,and the detected face bounding box is cropped by a specified multiple,then brightness equalization is adopted to perform brightness compensation on different brightness areas of the face ***,data features are extracted and classification is given by utilizing a 12-layer convolution neural *** of the proposed algorithm were carried out on *** results show that the classification accuracy is relatively high,and the half total error rate(HTER)reaches 1.02%.

关键词： face anti-spoofing MTCNN brightness equalization convolutional neural network

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盐酸米安色林鼻用制剂的处方前研究

中南药学 2024年第7期22卷 1789-1794页

作者：王猜谷福根杨蕾内蒙古医科大学药学院呼和浩特010110 内蒙古医科大学附属医院呼和浩特010050

目的研究盐酸米安色林(MIA)的平衡溶解度、表观油水分配系数(P_(app))及溶液化学稳定性,并筛选其经鼻黏膜吸收的理想促渗剂,为制备该药鼻腔给药新制剂提供理论依据。方法采用HPLC法测定MIA的含量及其在不同溶剂中的平衡溶解度;通过摇瓶... 详细信息

目的研究盐酸米安色林(MIA)的平衡溶解度、表观油水分配系数(P_(app))及溶液化学稳定性,并筛选其经鼻黏膜吸收的理想促渗剂,为制备该药鼻腔给药新制剂提供理论依据。方法采用HPLC法测定MIA的含量及其在不同溶剂中的平衡溶解度;通过摇瓶法测定药物在正辛醇-水及正辛醇-不同pH缓冲液体系中的P_(app);在80℃高温下放置,测定MIA在不同pH缓冲液中的降解百分率;以离体羊鼻黏膜为模型,采用Franz扩散池法完成药物体外渗透试验。结果MIA在不同溶剂中平衡溶解度的大小顺序为:丙二醇>5%DM-β-CD>5%HP-β-CD>1%F68>PEG400>5%SBE-β-CD>水;药物在酸性与中性pH下其平衡溶解度较大,而在碱性pH下很低。在正辛醇-不同pH缓冲液体系中,MIA的P_(app)随介质pH升高,呈增大趋势;此外,当介质pH<6.0时,MIA溶液的化学稳定性较差,当pH≥6.0时,其稳定性较好。4种候选促渗剂对MIA经鼻黏膜吸收均有明显促进作用,以5%DM-β-CD的促渗效果最佳。结论3种β-CD水溶性衍生物均可增加MIA的溶解度;pH值对MIA的平衡溶解度、P_(app)及溶液化学稳定性均有明显影响;DM-β-CD可能是MIA鼻用制剂的理想增溶剂及促渗剂。

关键词：盐酸米安色林鼻腔给药处方前研究平衡溶解度表观油水分配系数溶液化学稳定性促渗剂

解耦表征学习视角下认知图像属性特征的图像生成方法

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模式识别与人工智能 2024年第7期37卷 638-651页

作者：蔡江海黄成泉王顺霞罗森艳杨贵燕周丽华贵州民族大学贵州省模式识别与智能系统重点实验室贵阳550025 贵州民族大学数据科学与信息工程学院贵阳550025 贵州民族大学工程技术人才实践训练中心贵阳550025

在生成式人工智能领域,解耦表征学习的研究进一步推动图像生成方法的发展,但现有的解耦方法更多地关注图像生成的低维表示,忽略目标变化图像内在的可解释因素,导致生成的图像容易受到其它不相关属性特征的影响.为此,文中提出解耦表征学... 详细信息

在生成式人工智能领域,解耦表征学习的研究进一步推动图像生成方法的发展,但现有的解耦方法更多地关注图像生成的低维表示,忽略目标变化图像内在的可解释因素,导致生成的图像容易受到其它不相关属性特征的影响.为此,文中提出解耦表征学习视角下认知图像属性特征的图像生成方法.首先,从生成模型的潜在空间出发,通过训练获得关于目标变化图像的候选遍历方向.然后,构建无监督语义分解策略,并基于候选遍历的方向联合发现嵌入在潜在空间中的可解释方向.最后,利用解耦编码器和对比学习构建对比模拟器和变化空间,进而由可解释方向提取目标变化图像的解耦表征并生成图像.在5个解耦数据集上的实验表明文中方法性能较优.

关键词：解耦表征学习潜在空间可解释方向图像生成变化空间

Visualization of COVID-19 spread based on spread and extinction indexes

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Science China(Information Sciences) 2020年第6期63卷 220-222页

作者： Song-Hai ZHANG Yun cai Jian LI Department of Computer Science and Technology Tsinghua University Beijing National Research Center for Information Science and Technology(BNRist)

From December 2019, Coronavirus disease 2019(COVID-19) rapidly spread from the city of Wuhan (Hubei Province) to all of China, which was exacerbated by mass population movements associated with the Chinese Spring Festival. To date, more than 80000 people have been infected,and more than 3000 have died. In addition,COVID-19 has already spread to 142 countries,

关键词： Visualization of COVID-19 spread based on spread and extinction indexes

Enhanced resonance frequency in Co2FeAl thin film with different thicknesses grown on flexible graphene substrate

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Chinese Physics B 2024年第3期33卷 618-622页

作者：周偲袁少康朱登玉白宇明王韬刘福福潘禄禄冯存芳张博涵何大平汪胜祥 Hubei Engineering and Technology Research Center for Functional Fiber Fabrication and Testing Wuhan Textile UniversityWuhan 430200China School of Electronic and Electrical Engineering Wuhan Textile UniversityWuhan 430200China School of Mathematical and Physical Sciences Wuhan Textile UniversityWuhan 430200China School of Integrated Circuits Huazhong University of Science and TechnologyWuhan 430074China Key Laboratory for Magnetism and Magnetic Materials Ministry of EducationLanzhou UniversityLanzhou 730000China Beijing National Center for Condensed Matter Physics and Institute of Physics Chinese Academy of SciencesBeijing 100190China Hubei Engineering Research Center of RF-Microwave Technology and Application Wuhan University of TechnologyWuhan 430070China

The flexible materials exhibit more favorable properties than most rigid substrates in flexibility,weight saving,mechanical reliability,and excellent environmental ***,flexible graphene film with unique mechanical properties was extensively explored in high frequency ***,we report the characteristics of structure and magnetic properties at high frequency of Co2FeAl thin film with different thicknesses grown on flexible graphene substrate at room *** exciting finding for the columnar structure of Co2FeAl thin film lays the foundation for excellent high frequency property of Co2FeAl/flexible graphene ***-plane magnetic anisotropy field varying with increasing thickness of Co2FeAl thin film can be obtained by measurement of ferromagnetic resonance,which can be ascribed to the enhancement of crystallinity and the increase of grain ***,the resonance frequency which can be achieved by the measurement of vector network analyzer with the microstrip method increases with increasing thickness of Co2FeAl thin ***,in our case with graphene film,the resonance magnetic field is quite stable though folded for twenty cycles,which demonstrates that good flexibility of graphene film and the stability of high frequency magnetic property of Co2FeAl thin film grown on flexible graphene *** results are promising for the design of microwave devices and wireless communication equipment.

关键词： enhanced resonance frequency magnetic resonance field flexible graphene substrate