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Ocular syphilis:a case series of four patients and a review of the literature
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作者 Madeline Beckman Lana M.Rifkin 《Annals of Eye Science》 2024年第2期62-70,共9页
Background:The incidence of syphilis has been increasing in the United States over the last two decades,with a more recent increase among women.Ocular syphilis is an uncommon but important complication of syphilis,mos... Background:The incidence of syphilis has been increasing in the United States over the last two decades,with a more recent increase among women.Ocular syphilis is an uncommon but important complication of syphilis,most often presenting as posterior or panuveitis in late or latent syphilis of unknown duration.Untreated ocular syphilis may lead to permanent vision loss,underscoring the importance of appropriate evaluation and treatment of ocular syphilis.Case Description:In a retrospective,non-contiguous case series,we highlight four patients diagnosed and treated with ocular syphilis at a single institution.Four presentations of ocular syphilis are illustrated:anterior and intermediate uveitis,optic neuritis,posterior uveitis,and panuveitis.All patients initially presented with a decreased visual acuity(VA).One patient had a previous diagnosis of human immunodeficiency virus(HIV).Three patients were treated with intravenous(IV)penicillin and one patient with IV ceftriaxone.All had a return to their baseline VA after their course of treatment.Conclusions:Syphilis may go undetected without a high index of clinical suspicion due to its nonspecific presentations.All patients with ocular inflammation should have syphilis testing as a part of their infectious workup with both treponemal and non-treponemal testing.Patients diagnosed with syphilis and are not known to be HIV-negative should undergo testing for HIV due to the high rate of co-infection.Early diagnosis and prompt treatment after onset of symptoms may contribute to a more favorable prognosis for ocular syphilis. 展开更多
关键词 Ocular syphilis UVEITIS CHOROIDITIS intermediate uveitis case series
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PS-modules over Rings of Generalized Power Series 被引量:1
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作者 刘仲奎 《Northeastern Mathematical Journal》 CSCD 2002年第3期254-260,共7页
Let R be a commutative ring and (S, ≤) a strictly totally ordered monoid which satisfies the condition that 0 ≤ s for every s ∈ S. In this paper we show that if RM is a PS-module, then the module [[MS≤]] of genera... Let R be a commutative ring and (S, ≤) a strictly totally ordered monoid which satisfies the condition that 0 ≤ s for every s ∈ S. In this paper we show that if RM is a PS-module, then the module [[MS≤]] of generalized power series over M is a PS [[RS,≤]]-module. 展开更多
关键词 PS-module ring of generalized power series module of generalized power series
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Modelling Study of Magnetic Field Effect on the Performance of a Silicon Photovoltaic Module
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作者 Dioari Ulrich Combari Issa Zerbo +2 位作者 Martial Zoungrana Emmanuel Wendsongre Ramde Dieudonné Joseph Bathiebo 《Energy and Power Engineering》 2017年第8期419-429,共11页
Solar Photovoltaic is a very promising solution that can greatly contribute in solving the increasing global energy demand. In both rural and urban areas, photovoltaic modules are in some instances installed close to ... Solar Photovoltaic is a very promising solution that can greatly contribute in solving the increasing global energy demand. In both rural and urban areas, photovoltaic modules are in some instances installed close to telecommunication antennas or voltage transformers which generate important magnetic fields in their vicinity. The question is whether or not these magnetic fields affect the performances of the photovoltaic installations. This article presents a modelling study of external magnetic field effect on the electrical parameters of a photovoltaic module. The photocurrent, the photovoltage, the electric power, the series and the shunt resistances of the photovoltaic module, made up of ideal cells, are deduced from those of a silicon solar cell. Then, the I-V and P-V curves are plotted and the theoretical values of the electrical parameters of the photovoltaic module are deduced. The series and shunt resistances of the photovoltaic module are calculated using well known equations and the previous electrical parameters. The results show the negative effect of magnetic field on the performance of a solar photovoltaic module. 展开更多
关键词 CONVERSION Efficiency Magnetic Field MODELLING STUDY PHOTOVOLTAIC module series RESISTANCE SHUNT RESISTANCE
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Simple Bounded Weight Modules for the Vector Field Lie Algebras of Infinite Rank
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作者 NIU Meng-nan 《Chinese Quarterly Journal of Mathematics》 2020年第2期194-198,共5页
In this paper,we classify the simple uniformly bounded weight modules for the vector eld Lie algebra W1 of in nite rank.It turns out that any such modules are intermediate series modules.This result is very di erent f... In this paper,we classify the simple uniformly bounded weight modules for the vector eld Lie algebra W1 of in nite rank.It turns out that any such modules are intermediate series modules.This result is very di erent from the vector eld Lie algebra Wd of nite rank. 展开更多
关键词 Vector eld Lie algebra Weight module intermediate series module
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Investigation of the Performance of CIS Photovoltaic Modules under Different Environmental Conditions
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作者 Kandil M. Kandil Majida S. Altouq +3 位作者 Asma M. Al-asaad Latifa M. Alshamari Ibrahim M. Kadad Adel A. Ghoneim 《Smart Grid and Renewable Energy》 2011年第4期375-387,共13页
This work investigates the effects of temperature and radiation intensity on the parameters of a copper indium diselenide (CIS) photovoltaic module. The module performance parameters are determined from calculated mod... This work investigates the effects of temperature and radiation intensity on the parameters of a copper indium diselenide (CIS) photovoltaic module. The module performance parameters are determined from calculated module parameters. An outdoor experimental setup is installed to carryout a series of I-V curve measurements under different irradiance and temperature conditions for the module. A numerical model which considers the effect of series and shunt resistances is developed to evaluate the different parameters of PV modules. Orthogonal distance regression (ODR) algorithm is adapted for fitting I-V measurements and extracting module parameters from I-V measurements. The values of module parameters, series resistance Rs, shunt resistance Rsh, diode ideality factor n and reverse saturation current Io determined from I-V measurements at different irradiation intensity and temperature range are in good agreement with the corresponding parameters obtained from the developed numerical model. The module parameters extracted from I-V measurements are employed to calculate the module performance parameters, i.e. open circuit voltage Voc, fill factor FF and module efficiency η at different irradiation intensity and temperature range. Present results indicate that the largest drop in open circuit voltage Voc due to about 20℃ increase in temperature is approximately 8.8% which is not compensated for by the relatively small increase in short circuit current, (2.9% in Isc), resulting in a reduction in maximum power of about 6.3%. Results let us conclude that the shunt resistance RSh increases with radiation at low radiation values (2). As radiation increases at high radiation values (> 400 W/m2), RSh begins to decease sharply and dramatically. Also, as the light intensity incident on the solar module increases, the series resistance and the output voltage decrease. When the irradiance intensity increases, the series resistance decreases but with a very low rate at the two studied temperatures ranges. The low rate decrease of Rs is found to have little effect on module performance in comparison with the significant change of other module parameters. The ideality factor n and saturation current Io decrease first sharply in the low range of radiation intensity (2) and this decrease becomes smaller for irradiance values greater than 400 W/m2. The previous observations and conclusions regarding the module parameters RSh, RS, n and Io obtained at 20℃ observed again at 40℃ but there is a great difference between the peak values of RSh at both temperature levels. Present results also show that module efficiency decreases with increasing irradiance intensity due to the combined effect of both Voc and FF. 展开更多
关键词 PV module module Parameters series RESISTANCE SHUNT RESISTANCE IDEALITY FACTOR
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基于OFDM的无线信号与电能反向同步传输方法
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作者 靖永志 鲁林海 +2 位作者 冯伟 王森 孙希聪 《电子与信息学报》 EI CSCD 北大核心 2023年第8期2856-2866,共11页
无线电能传输系统的稳定运行离不开信息传输技术的实现,该文针对无线信号与电能共享通道传输时存在耦合干扰及频谱利用率低的问题,提出一种基于正交频分复用技术(OFDM)的信号与电能反向同步传输新方法。该方法将电能载波等效为搭载全1... 无线电能传输系统的稳定运行离不开信息传输技术的实现,该文针对无线信号与电能共享通道传输时存在耦合干扰及频谱利用率低的问题,提出一种基于正交频分复用技术(OFDM)的信号与电能反向同步传输新方法。该方法将电能载波等效为搭载全1信息的信号载波,采用OFDM技术实现信号的同步解耦与高速可靠传输时,即可减少电能传输过程对信号传输过程产生的串扰。电能通道采用串联谐振(S/LCC)补偿拓扑结构,使负载在一定范围内变化时输出电压稳定。松耦合变压器作为电能和信号传输的共同通道,可以同时、反向传输信号与电能两种不同频率的载波。首先介绍了系统的结构和OFDM基本原理;其次,对系统进行数学建模,分析研究信号与电能的传输特性;在此基础上,给出了信号调制与解调的设计方法。最后搭建电能传输功率为20 W、信号传输速率为85 kbit/s的实验平台,验证了所提方法的正确性。 展开更多
关键词 无线信号传输 正交频分复用 信号调制/解调 S/LCC补偿
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CONVERGENCE AND GROWTH OF MULTIPLE DIRICHLET SERIES 被引量:5
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作者 梁美丽 高宗升 《Acta Mathematica Scientia》 SCIE CSCD 2010年第5期1640-1648,共9页
This article investigates the convergence and growth of multiple Dirichlet series. The Valiron formula of Dirichlet series is extended to n-tuple Dirichlet series and an equivalence relation between the order of n-tup... This article investigates the convergence and growth of multiple Dirichlet series. The Valiron formula of Dirichlet series is extended to n-tuple Dirichlet series and an equivalence relation between the order of n-tuple Dirichlet series and its coefficients and exponents is obtained. 展开更多
关键词 multiple Dirichlet series convergent abscissa maximal module maximal term order
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A Study of Visual Recognition of Facial Emotional Expressions in a Normal Aging Population in the Absence of Cognitive Disorders
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作者 Philippe Granato Shreekumar Vinekar +2 位作者 Olivier Godefroy Jean-Pierre Vangansberghe Raymond Bruyer 《Open Journal of Psychiatry》 2014年第3期251-260,共10页
Objective: To examine and measure the decision-making processes involved in Visual Recognition of Facial Emotional Expressions (VRFEE) and to study the effects of demographic factors on this process. Method: We evalua... Objective: To examine and measure the decision-making processes involved in Visual Recognition of Facial Emotional Expressions (VRFEE) and to study the effects of demographic factors on this process. Method: We evaluated a newly designed software application (M.A.R.I.E.) that permits computerized metric measurement of VRFEE. We administered it to 204 cognitively normal participants ranging in age from 20 to 70 years. Results: We established normative values for the recognition of anger, disgust, joy, fear, surprise and sadness expressed on the faces of three individuals. There was a significant difference in the: 1) measurement (F (8.189) = 3896, p = 0.0001);2) education level (x2(12) = 28.4, p = 0.005);3) face (F(2.195) = 10, p = 0.0001);4)series (F (8.189)=28, p = 0.0001);5) interaction between the identity and recognition of emotions (F (16, 181 =11, p = 0.0001). However, performance did not differ according to: 1) age (F (6.19669) = 1.35, p = 0.2) or 2) level of education (F (1, 1587) = 0.6, p = 0.4). Conclusions: In healthy participants, the VRFEE remains stable throughout the lifespan when cognitive functions remain optimal. Disgust, sadness, fear, and joy seem to be the four most easily recognized facial emotions, while anger and surprise are not easily recognized. Visual recognition of disgust and fear is independent of aging. The characteristics of a face have a significant influence on the ease with which people recognize expressed emotions (idiosyncrasy). Perception and recognition of emotions is categorical, even when the facial images are integrated in a spectrum of morphs reflecting two different emotions on either side. 展开更多
关键词 RECOGNITION Emotions M.A.R.I.E. Aging Healthy PARTICIPANTS EMOTION STIMULUS (ES) EMOTION Set (ESet) EMOTION series (ESr) VRFEE EMOTION RECOGNITION (ER) Canonical Emotions (CE) intermediate Emotions (IE)
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Simulation of Intermediate State Absorption Enhancement in Rare-Earth Ions by Polarization Modulated Femtosecond Laser Field
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作者 Wen-Jing Cheng Shi-Hua Zhao 《Chinese Physics Letters》 SCIE CAS CSCD 2018年第11期23-27,共5页
We extend the third perturbation theory to study the polarization control behavior of the intermediate state absorption in Nd^(3+)ions. The results show that coherent interference can occur between the single-photo... We extend the third perturbation theory to study the polarization control behavior of the intermediate state absorption in Nd^(3+)ions. The results show that coherent interference can occur between the single-photon and three-photon excitation pathways, and depends on the central frequency of the femtosecond laser field. Moreover,single-photon and three-photon absorptions have different polarization control efficiencies, and the relative weight of three-photon absorption in the whole excitation processes can increase with increasing the laser intensity.Therefore, the enhancement or suppression of the intermediate state absorption can be realized and manipulated by properly designing the intensity and central frequency of the polarization modulated femtosecond laser field.This research can not only enrich theoretical research methods for the up-conversion luminescence manipulation of rare-earth ions, but also can provide a clear physical picture for understanding and controlling multi-photon absorption in a multiple energy level system. 展开更多
关键词 ab Simulation of intermediate State Absorption Enhancement in Rare-Earth Ions by Polarization Modulated Femtosecond Laser Field
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The Theses of Master in 2001
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《IMP & HIRFL Annual Report》 2001年第1期174-174,共1页
1) CSR Web Site and Net Database Construction.2)Wang Yiguo.Customer Self-Service Bank Integrated Application System.Qin Lin.3)Design of CAMAC Drivet for Windows 2000. Hu Jianjun.4) Detailed Dynamics of Slow Extraction... 1) CSR Web Site and Net Database Construction.2)Wang Yiguo.Customer Self-Service Bank Integrated Application System.Qin Lin.3)Design of CAMAC Drivet for Windows 2000. Hu Jianjun.4) Detailed Dynamics of Slow Extraction. Wu Junli. 展开更多
关键词 ELECTRON DRIVER intermediate module SWIFT Ground
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Spectral Calculation of the Output Voltage of an Inverter with Bipolar Pulse Width Modulation
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作者 Mreela V. Sunde Z. Beneie 《Journal of Energy and Power Engineering》 2010年第8期48-56,共9页
Converters with pulse width modulation are used for connections between the direct current (DC) and alternating current (AC) networks, e.g., in uninterrupted power supply systems, AC electromotor drives, for power... Converters with pulse width modulation are used for connections between the direct current (DC) and alternating current (AC) networks, e.g., in uninterrupted power supply systems, AC electromotor drives, for powering induction furnaces, in audio technique. Spectrum of signals sampled by pulse amplitude modulation and output voltage spectrum of the converter with pulse width modulation have similar properties. Spectrum of signals sampled by pulse amplitude modulation contains a harmonic of frequency equal to the frequency of the modulating signal and the harmonics of frequencies equal to the sum of frequency of the modulating signal and multiples of the sampling frequency. The output voltage spectrum of the converter with bipolar pulse width modulation contains harmonic of frequency equal to the frequency of the modulating signal and harmonics of frequencies equal to sum of the frequency of the modulating signal and multiples of the frequency of the carrier signal. It also contains harmonics of frequencies equal to the sum of the multiples of the frequency of the modulating signal and the multiples of the carrier signal. The comparison analysis was carried out for the harmonics of the output voltage of the converter with bipolar pulse width modulation in time domain. The dependency of the amplitudes and frequency spectrum on the wave forms of the carrier signal and modulating signal was shown. Similarity of the output voltage spectrum of the converter and signal spectrum sampled by the pulse width modulation was also shown. Key words: Output voltage converter with bipolar pulse width modulation, spectral analysis, Fourier series, carrier signal, reference signal. 展开更多
关键词 Output voltage converter with bipolar pulse width modulation spectral analysis Fourier series carrier signal referencesignal.
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Enhancing Grammar Learning with a Multimedia Instructional Module:Design and Teaching of“Shì...de”Construction for CFL learners
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作者 Shenglan Zhang 《汉语教学方法与技术》 2022年第1期1-28,共28页
This pilot study examined the effectiveness and students’perceptions of a multimedia module on intermediate Chinese-as-a-Foreign-Language(CFL)learners’understanding and use of the“shì...de”construction.The mo... This pilot study examined the effectiveness and students’perceptions of a multimedia module on intermediate Chinese-as-a-Foreign-Language(CFL)learners’understanding and use of the“shì...de”construction.The module was designed based on the First Principles of Instruction(Morrill,2002)and the Cognitive Theory of Multimedia Learning(Mayer,2009;2014).It provided a systematic and comprehensive approach to teaching the“shì...de”construction,one of the most challenging grammar points in CFL.Twenty-two CFL learners participated in this mixed-methods study.Data were collected using pre-and post-tests,a survey,think-alouds,and semi-structured interviews.Findings show that after using the module,students’understanding and use of the construction significantly improved,except for their understanding of the second usage.The students enjoyed using the module and appreciated how it was designed,the way it was presented,and its availability.The reasons for the effectiveness of the module were analyzed and led to suggested improvements to the design of the module.The detailed description of the design process and the research result contribute to the knowledge of designing grammar teaching modules with multimedia for online,blended,and flipped learning. 展开更多
关键词 “shì...de”construction intermediate CFL learners multimedia in teaching grammar online instructional module CFL grammar
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Indecomposable modules of the intermediate series over W(a,b) 被引量:3
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作者 SU YuCai XU Ying YUE XiaoQing 《Science China Mathematics》 SCIE 2014年第2期275-291,共17页
For any complex parameters a and b,W(a,b)is the Lie algebra with basis{Li,Wi|i∈Z}and relations[Li,Lj]=(j i)Li+j,[Li,Wj]=(a+j+bi)Wi+j,[Wi,Wj]=0.In this paper,indecomposable modules of the intermediate series over W(a,... For any complex parameters a and b,W(a,b)is the Lie algebra with basis{Li,Wi|i∈Z}and relations[Li,Lj]=(j i)Li+j,[Li,Wj]=(a+j+bi)Wi+j,[Wi,Wj]=0.In this paper,indecomposable modules of the intermediate series over W(a,b)are classified.It is also proved that an irreducible Harish-Chandra W(a,b)-module is either a highest/lowest weight module or a uniformly bounded module.Furthermore,if a∈/Q,an irreducible weight W(a,b)-module is simply a Vir-module with trivial actions of Wk’s. 展开更多
关键词 the algebra W(a b) the Virasoro algebra modules of the intermediate series
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基于残差卷积网络的多传感器融合永磁同步电机故障诊断
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作者 邱建琪 沈佳晨 +2 位作者 史涔溦 史婷娜 李鸿杰 《电机与控制学报》 EI CSCD 北大核心 2024年第7期24-33,42,共11页
作为工业生产与日常生活的常见设备,永磁同步电机的故障诊断研究具有十分重要的意义。以永磁同步电机的匝间短路、退磁、轴承故障为诊断目标,提出一种新型的多传感器特征融合网络(MSFFN),结合多传感器融合技术与卷积神经网络实现永磁同... 作为工业生产与日常生活的常见设备,永磁同步电机的故障诊断研究具有十分重要的意义。以永磁同步电机的匝间短路、退磁、轴承故障为诊断目标,提出一种新型的多传感器特征融合网络(MSFFN),结合多传感器融合技术与卷积神经网络实现永磁同步电机的可靠故障诊断。网络采用2个带有残差模块的卷积神经网络,对输入的电流信号与振动信号并行提取隐藏特征,并设计一种中间特征融合模块(IFFM)有效融合电流和振动的各层隐藏特征,IFFM基于注意力机制对网络中的电流特征与振动特征进行筛选,自适应关注不同信号的内在相关特征,以实现更好的诊断效果。搭建了故障样机测试平台进行数据采集与实验验证,实验结果表明,提出方法具有更高的诊断准确率,同时在叠加了强噪声的条件下,具备更强的抗干扰能力。 展开更多
关键词 多传感器融合 卷积神经网络 中间特征融合模块 残差模块 永磁同步电机 故障诊断
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适用过程模拟的等熵多级压缩机模块开发
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作者 陈玉石 赵芳磊 王建平 《石油化工自动化》 CAS 2024年第3期29-35,共7页
基于国产化工过程模拟软件,开发了针对具有多流股中间级进出料的等熵多级压缩机单元模块。首先建立了多级串联等熵压缩和中间换热的数学模型以及求解步骤,然后利用面向对象的C++语言和COM组件技术开发了等熵多级压缩机模块,最后采用轻... 基于国产化工过程模拟软件,开发了针对具有多流股中间级进出料的等熵多级压缩机单元模块。首先建立了多级串联等熵压缩和中间换热的数学模型以及求解步骤,然后利用面向对象的C++语言和COM组件技术开发了等熵多级压缩机模块,最后采用轻烃压缩、催化裂化装置的富气压缩等工段的实际数据校验模块计算准确性。结果表明,压缩机功率与冷凝器热负荷平均相对偏差分别为0.80%和0.39%,压缩机出口物流组成平均相对偏差分别为0.77%和0.73%,压缩机出口物流流量与密度平均相对偏差分别为0.15%和0.46%。实际案例验证表明,模拟结果与工业实际值吻合良好,说明等熵多级压缩机模块稳定可靠,对化工流程中气体压缩过程的模拟计算具有重要的指导作用。 展开更多
关键词 多级压缩机 等熵模型 模块开发 中间级进出料
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一种基于时间序列分解和时空信息提取的云服务器异常检测模型
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作者 唐伦 赵禹辰 +1 位作者 薛呈呈 陈前斌 《电子与信息学报》 EI CAS CSCD 北大核心 2024年第6期2638-2646,共9页
异常检测是维护云数据中心性能的一项重要任务。云数据中心中运行着大量的云服务器以实现各种云计算功能。由于云数据中心的性能取决于云服务的正常运行,因此检测和分析云服务器中的异常至关重要。为此,该文提出一种基于时间序列分解和... 异常检测是维护云数据中心性能的一项重要任务。云数据中心中运行着大量的云服务器以实现各种云计算功能。由于云数据中心的性能取决于云服务的正常运行,因此检测和分析云服务器中的异常至关重要。为此,该文提出一种基于时间序列分解和时空信息提取的云服务器异常检测模型。首先,提出带时空信息提取模块的双向Wasserstein生成对抗网络算法(BiWGAN-GTN),该算法在具有梯度惩罚的双向Wasserstein生成对抗网络(BiWGAN-GP)算法的基础上,将生成器与编码器替换为由图卷积网络(GCN)与时间卷积网络(TCN)组成的时空信息提取模块(GTN),实现对数据空时信息的提取;其次,提出半监督BiWGAN-GTN算法来识别多维时间序列中的异常,以在训练过程中避免异常数据侵入的风险并增强模型鲁棒性。最后设计多通道BiWGAN-GTN算法-MCBiWGAN-GTN以实现降低数据复杂度并提升模型学习效率的目标。利用带有自适应噪声完全集合经验模态分解(CEEMDAN)算法将时序数据分解,然后将不同的分量送入对应通道下的BiWGAN-GTN算法中训练。在真实世界云数据中心数据集Clearwater和MBD上采用精确率、召回率和F1分数这3个性能指标验证了该文所提模型的有效性。实验结果表明,MCBiWGAN-GTN在这两个数据集上的性能稳定并优于所比较的方法。 展开更多
关键词 云服务器异常检测 时间序列分解 生成对抗网络 时空信息提取模块
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Classification of Indecomposable Modules of the Intermediate Series over Deformative Schrodinger-Virasoro Lie Algebras 被引量:1
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作者 Wei Wang Ying Xu Taijie You 《Algebra Colloquium》 SCIE CSCD 2014年第2期295-306,共12页
A classification of indecomposable modules of the intermediate series over the deformative Schr&dinger-Virasoro Lie algebras is obtained.
关键词 modules of the intermediate series Virasoro algebra Schrgdinger algebra
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电气化铁路“车-网”系统串/并联双模式宽频谐波扰动产生装置设计与测量方法 被引量:1
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作者 杨向阳 胡海涛 +3 位作者 肖冬华 陶海东 宋依桐 何正友 《中国电机工程学报》 EI CSCD 北大核心 2024年第13期5109-5121,I0008,共14页
精确测量动车组与电力机车(简称机车)四象限变流器(four-quadrant converter,4QC)和牵引网的宽频带阻抗特性是识别电气化铁路“车-网”系统振荡和不稳定问题的重要途径。然而,已有研究采用单一电压/电流扰动注入方式对牵引网或机车4QC... 精确测量动车组与电力机车(简称机车)四象限变流器(four-quadrant converter,4QC)和牵引网的宽频带阻抗特性是识别电气化铁路“车-网”系统振荡和不稳定问题的重要途径。然而,已有研究采用单一电压/电流扰动注入方式对牵引网或机车4QC阻抗进行测量,可能造成部分谐波扰动流向非目标测量对象,导致被测对象的谐波扰动信噪比低,影响阻抗测量精度。因此,该文提出一种适用于电气化铁路“车-网”联合系统的串/并联双模式宽频谐波扰动产生装置与阻抗测量方法,装置具有电压和电流两种工作模式,可以发出频带为1~3000Hz的宽频谐波扰动。扰动产生装置拓扑主要由多绕组降压变压器、谐波功率放大单元、并联LC谐振电路和反串联绝缘栅双极晶体管(insulated gate bipolar transistor,IGBT)模块等部分构成,结合双闭环dq解耦控制和载波移相开环脉宽调制(pulse-width modulation,PWM)控制策略,实现频带双边可控、幅值可控且分布均匀的大功率谐波扰动输出。最后,利用MATLAB/Simulink仿真和RT-Lab硬件在环实验验证该文串/并联双模式宽频谐波扰动产生装置设计方案及阻抗测量方法的正确性与有效性。 展开更多
关键词 电气化铁路“车-网”系统 串/并联双模式 宽频谐波扰动产生装置 并联LC谐振电路 反串联IGBT模块
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Harish-Chandra Modules of the Intermediate Series over the Topological N = 2 Superconformal Algebra
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作者 Hengyun Yang Ying Xu Jiancai Sun 《Algebra Colloquium》 SCIE CSCD 2020年第2期343-360,共18页
The topological N=2 superconformal algebra was introduced by Dijkgraaf,Verlinde and Verlinde as the symmetry algebra of topological strings at d<1.We give a classification of irreducible Z×Z-graded modules of ... The topological N=2 superconformal algebra was introduced by Dijkgraaf,Verlinde and Verlinde as the symmetry algebra of topological strings at d<1.We give a classification of irreducible Z×Z-graded modules of the intermediate series over this infinite-dimensional Lie superalgebra. 展开更多
关键词 topological N=2 superconformal algebra modules of intermediate series Harish-Chandra modules
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Modules of the Intermediate Series over Not-finitely Graded Lie Algebras W(Г)
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作者 Yadi Wu Xiaoqing Yue 《Algebra Colloquium》 SCIE CSCD 2021年第2期319-336,共18页
Let W(Г)be a class of not-finitely graded Lie algebras related to generalized Virasoro algebras with basis{L_(α,i),C|α∈Г,i∈Z_(+)},which satisfies relations[L_(α,i),L_(β,j)]=L_(α+β,i+j)+(j-i)L_(α+β,i+j+1)+... Let W(Г)be a class of not-finitely graded Lie algebras related to generalized Virasoro algebras with basis{L_(α,i),C|α∈Г,i∈Z_(+)},which satisfies relations[L_(α,i),L_(β,j)]=L_(α+β,i+j)+(j-i)L_(α+β,i+j+1)+δ_(α+β,0)δ_(i+j),0α^(3)-α/12 C and[C,L_(α,i)]=0.In this paper,W(Г)-modules of the intermediate series satisfying some conditions are constructed and classified.We also obtain modules of the intermediate series over the related Lie superalgebra. 展开更多
关键词 modules of intermediate series generalized Virasoro algebras not-finitely graded Lie algebras Lie superalgebras
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