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Single event effects evaluation on convolution neural network in Xilinx 28 nm system on chip
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作者 赵旭 杜雪成 +4 位作者 熊旭 马超 杨卫涛 郑波 周超 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期638-644,共7页
Convolutional neural networks(CNNs) exhibit excellent performance in the areas of image recognition and object detection, which can enhance the intelligence level of spacecraft. However, in aerospace, energetic partic... Convolutional neural networks(CNNs) exhibit excellent performance in the areas of image recognition and object detection, which can enhance the intelligence level of spacecraft. However, in aerospace, energetic particles, such as heavy ions, protons, and alpha particles, can induce single event effects(SEEs) that lead CNNs to malfunction and can significantly impact the reliability of a CNN system. In this paper, the MNIST CNN system was constructed based on a 28 nm systemon-chip(SoC), and then an alpha particle irradiation experiment and fault injection were applied to evaluate the SEE of the CNN system. Various types of soft errors in the CNN system have been detected, and the SEE cross sections have been calculated. Furthermore, the mechanisms behind some soft errors have been explained. This research will provide technical support for the design of radiation-resistant artificial intelligence chips. 展开更多
关键词 single event effects convolutional neural networks alpha particle system on chip fault injection
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Scalable single sign-on system 被引量:2
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作者 黄河 单志广 黄冬泉 《Journal of Southeast University(English Edition)》 EI CAS 2007年第3期465-468,共4页
To address the scalability and identity federation problems of the traditional single sign-on system, the proposed scheme divides the security systems into different security domains. Each security domain has its own ... To address the scalability and identity federation problems of the traditional single sign-on system, the proposed scheme divides the security systems into different security domains. Each security domain has its own security servers and service providers, and there are trust relationships between different security domains for identity federation. The security server is responsible for authentication and authorization inside the domain, and offers identity federation capability for different domains. The security assertion markup language (SAML) assertion is used as security token in the system for authentication, authorization, and identity federation. The design of the proposed single sign-on process is based on web service security framework and multiple security domains, and the authorization is always deployed in the local area inside the service provider' s security domain, which enables web service clients, both inside and outside their security domains, to access the services in a simple, scalable, standard and secure way. 展开更多
关键词 security systems ARCHITECTURE web service single sign-on identity federation
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Fault tolerant control of electric pitch control system based on single current detection
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作者 李宏伟 付勃 +2 位作者 董海鹰 杨立霞 王睿敏 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2016年第1期63-70,共8页
In view of the current sensors failure in electric pitch system,a variable universe fuzzy fault tolerant control method of electric pitch control system based on single current detection is proposed.When there is sing... In view of the current sensors failure in electric pitch system,a variable universe fuzzy fault tolerant control method of electric pitch control system based on single current detection is proposed.When there is single or two-current sensor fault occurs,based on the proposed method the missing current information can be reconstructed by using direct current(DC)bus current sensor and the three-phase current can be updated in time within any two adjacent sampling periods,so as to ensure stability of the closed-loop system.And then the switchover and fault tolerant control of fault current sensor would be accomplished by fault diagnosis method based on adaptive threshold judgment.For the reconstructed signal error caused by the modulation method and the main control target of electric pitch system,a variable universe fuzzy control method is used in the speed loop,which can improve the anti-disturbance ability to load variation,and the robustness of fault tolerance system.The results show that the fault tolerant control method makes the variable pitch control system still has ideal control characteristics in case of sensor failure although part of the system performance is lost,thus the correctness of the proposed method is verified. 展开更多
关键词 electric pitch control fault tolerant control variable universe fuzzy control single current detection
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Working Condition Real-Time Monitoring Model of Lithium Ion Batteries Based on Distributed Parameter System and Single Particle Model
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作者 黄亮 姚畅 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2016年第5期623-628,I0002,共7页
Lithium ion batteries are complicated distributed parameter systems that can be described preferably by partial differential equations and a field theory. To reduce the solution difficulty and the calculation amount, ... Lithium ion batteries are complicated distributed parameter systems that can be described preferably by partial differential equations and a field theory. To reduce the solution difficulty and the calculation amount, if a distributed parameter system is described by ordinary differential equations (ODE) during the analysis and the design of distributed parameter system, the reliability of the system description will be reduced, and the systemic errors will be introduced. Studies on working condition real-time monitoring can improve the security because the rechargeable LIBs are widely used in many electronic systems and electromechanical equipment. Single particle model (SPM) is the simplification of LIB under some approximations, and can estimate the working parameters of a LIB at the faster simulation speed. A LIB modelling algorithm based on PDEs and SPM is proposed to monitor the working condition of LIBs in real time. Although the lithium ion concentration is an unmeasurable distributed parameter in the anode of LIB, the working condition monitoring model can track the real time lithium ion concentration in the anode of LIB, and calculate the residual which is the difference between the ideal data and the measured data. A fault alarm can be triggered when the residual is beyond the preset threshold. A simulation example verifies that the effectiveness and the accuracy of the working condition real-time monitoring model of LIB based on PDEs and SPM. 展开更多
关键词 Lithium ion battery Distributed parameter system single particle model Condition monitoring
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Fast Gamma and Neutron Inspection Measurements in a Single System
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《国际原子能机构通报》 1997年第2期51-51,共1页
Safeguards Inspectors make a wide array of verificationmeasurements,involving multiple pieces of equipment.One of the biggest challenges facing the Inspector hasbeen the need to juggle Nal detectors,HpGe detectors,neu... Safeguards Inspectors make a wide array of verificationmeasurements,involving multiple pieces of equipment.One of the biggest challenges facing the Inspector hasbeen the need to juggle Nal detectors,HpGe detectors,neutron counters,MCAs and shift registers-while stilltaking the requisite measurements quickly and withminimal interruption to facility operations. 展开更多
关键词 IMCA Fast Gamma and Neutron Inspection Measurements in a single system JSR
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Single-incision laparoscopic appendectomy vs conventional laparoscopic appendectomy:Systematic review and meta-analysis 被引量:9
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作者 Yu-Long Cai Xian-Ze Xiong +5 位作者 Si-Jia Wu Yao Cheng Jiong Lu Jie Zhang Yi-Xin Lin Nan-Sheng Cheng 《World Journal of Gastroenterology》 SCIE CAS 2013年第31期5165-5173,共9页
AIM: To assess the differences in clinical benefits and disadvantages of single-incision laparoscopic appendectomy(SILA) and conventional laparoscopic appendectomy(CLA).METHODS: The Cochrane Library,MEDLINE,Embase,Sci... AIM: To assess the differences in clinical benefits and disadvantages of single-incision laparoscopic appendectomy(SILA) and conventional laparoscopic appendectomy(CLA).METHODS: The Cochrane Library,MEDLINE,Embase,Science Citation Index Expanded,and Chinese Biomedical Literature Database were electronically searched up through January 2013 to identify randomized controlled trails(RCTs) comparing SILA with CLA.Data was extracted from eligible studies to evaluate the pooled outcome effects for the total of 1068 patients.The meta-analysis was performed using Review Manager 5.2.0.For dichotomous data and continuous data,the risk ratio(RR) and the mean difference(MD) were calculated,respectively,with 95%CI for both.For continuous outcomes with different measurement scales in different RCTs,the standardized mean difference(SMD) was calculated with 95%CI.Sensitivity and subgroup analyses were performed when necessary.RESULTS: Six RCTs were identified that compared SILA(n = 535) with CLA(n = 533).Five RCTs had a high risk of bias and one RCT had a low risk of bias.SILA was associated with longer operative time(MD = 5.68,95%CI: 3.91-7.46,P < 0.00001),higher conversion rate(RR = 5.14,95%CI: 1.25-21.10,P = 0.03) and better cosmetic satisfaction score(MD = 0.52,95%CI: 0.30-0.73,P < 0.00001) compared with CLA.No significant differences were found for total complications(RR = 1.15,95%CI: 0.76-1.75,P = 0.51),drain insertion(RR = 0.72,95%CI: 0.41-1.25,P = 0.24),or length of hospital stay(SMD = 0.04,95%CI:-0.08-0.16,P = 0.57).Because there was not enough data among the analyzed RCTs,postoperative pain was not calculated.CONCLUSION: The benefit of SILA is cosmetic satisfaction,while the disadvantages of SILA are longer operative time and higher conversion rate. 展开更多
关键词 single INCISION LAPAROSCOPIC APPENDECTOMY META-ANALYSIS systematic review
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Analyses of Trawling Track and Fishing Activity Based on the Data of Vessel Monitoring System(VMS): A Case Study of the Single Otter Trawl Vessels in the Zhoushan Fishing Ground 被引量:12
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作者 WANG Yang WANG Yingbin ZHENG Ji 《Journal of Ocean University of China》 SCIE CAS 2015年第1期89-96,共8页
The original purpose of Vessel Monitoring System(VMS) is for enforcement and control of vessel sailing. With the application of VMS in fishing vessels, more and more population dynamic studies have used VMS data to im... The original purpose of Vessel Monitoring System(VMS) is for enforcement and control of vessel sailing. With the application of VMS in fishing vessels, more and more population dynamic studies have used VMS data to improve the accuracy of fisheries stock assessment. In this paper, we simulated the trawl trajectory under different time intervals using the cubic Hermite spline(c Hs) interpolation method based on the VMS data of 8 single otter trawl vessels(totally 36000 data items) fishing in Zhoushan fishing ground from September 2012 to December 2012, and selected the appropriate time interval. We then determined vessels' activities(fishing or non-fishing) by comparing VMS speed data with the corresponding speeds from logbooks. The results showed that the error of simulated trajectory greatly increased with the increase of time intervals of VMS data when they were longer than 30 minutes. Comparing the speeds from VMS with those from the corresponding logbooks, we found that the vessels' speeds were between 2.5 kn and 5.0 kn in fishing. The c Hs interpolation method is a new choice for improving the accuracy of estimation of sailing trajectory, and the VMS can be used to determine the vessels' activities with the analysis of their trajectories and speeds. Therefore, when the fishery information is limited, VMS can be one of the important data sources for fisheries stock assessment, and more attention should be paid to its construction and application to fisheries stock assessment and management. 展开更多
关键词 single otter trawls Zhoushan fishing ground Vessel Monitoring system (VMS) trajectory fishing activity
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Quantum entanglement in the system of two two-level atoms interacting with a single-mode vacuum field 被引量:9
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作者 曾可 方卯发 《Chinese Physics B》 SCIE EI CAS CSCD 2005年第10期2009-2013,共5页
The entanglement properties of the system of two two-level atoms interacting with a single-mode vacuum field are explored. The quantum entanglement between two two-level atoms and a single-mode vacuum field is investi... The entanglement properties of the system of two two-level atoms interacting with a single-mode vacuum field are explored. The quantum entanglement between two two-level atoms and a single-mode vacuum field is investigated by using the quantum reduced entropy; the quantum entanglement between two two-level atoms, and that between a single two-level atom and a single-mode vacuum field are studied in terms of the quantum relative entropy. The influences of the atomic dipole-dipole interaction on the quantum entanglement of the system are also discussed. Our results show that three entangled states of two atoms-field, atom-atom, and atom-field can be prepared via two two-level atoms interacting with a single-mode vacuum field. 展开更多
关键词 quantum entanglement single mode vacuum field reduced entropy relative entropy
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Design of Intelligent Fire Alarm System for Large Storage Places Based on AVRmega128 Single Chip Microcomputer
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作者 杨东星 李明儒 +1 位作者 刘南君 毛培宏 《Agricultural Science & Technology》 CAS 2014年第4期692-696,共5页
With principles of reliability, independence, practicality and economical effi- ciency, a set of intelligent fire alarm system based on AVRmega128 single chip microcomputer was designed to solve problems of fire alarm... With principles of reliability, independence, practicality and economical effi- ciency, a set of intelligent fire alarm system based on AVRmega128 single chip microcomputer was designed to solve problems of fire alarm system in many large- scale warehouses. Using advanced flame sensor, 485 bus communication, computer interactive software and related peripheral devices, this intelligent fire alarm system has functions of sound-light alarm and intelligent fire extinguishing. The human-com- puter interactive software was adopted for the remote control of the alarm main control panel through the 485 bus communication. This design of intelligent fire alarm system shows high reference and practical value to the development of intel- ligent alarm products with high integration and high reliability. 展开更多
关键词 AVRmega128 single chip microcomputer 485 bus communication Audi- ble and visual alarm Intelligent fire extinguishing Human-computer interaction
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Modified projective synchronization of a fractional-order hyperchaotic system with a single driving variable 被引量:4
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作者 王兴元 张永雷 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第10期159-165,共7页
In this paper, the modified projective synchronization (MPS) of a fractional-order hyperchaotic system is inves- tigated. We design the response system corresponding to the drive system on the basis of projective sy... In this paper, the modified projective synchronization (MPS) of a fractional-order hyperchaotic system is inves- tigated. We design the response system corresponding to the drive system on the basis of projective synchronization theory, and determine the sufficient condition for the synchronization of the drive system and the response system based on fractional-order stability theory. The MPS of a fractional-order hyperchaotic system is achieved by transmitting a single variable. This scheme reduces the information transmission in order to achieve the synchronization, and extends the applicable scope of MPS. Numerical simulations further demonstrate the feasibility and the effectiveness of the proposed scheme. 展开更多
关键词 modified projective synchronization fractional-order hyperchaotic system single drivingvariable
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Iterative Block DFE for Underwater Acoustic Single Carrier System 被引量:4
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作者 Sun Haixin Guo Yuhui +1 位作者 Kuai Xiaoyan Cheng En 《China Communications》 SCIE CSCD 2012年第7期121-126,共6页
Abstract: In order to gain a better performance and reduce the computational complexity of the filter design in the underwater acoustic single car rier system, a new Iterative Block DFE (IBDFE) is proposed, which o... Abstract: In order to gain a better performance and reduce the computational complexity of the filter design in the underwater acoustic single car rier system, a new Iterative Block DFE (IBDFE) is proposed, which operates iteratively on blocks of the received signal, and fully implements its filtering operations by Discrete Fourier Trans forms (DFTs). Two design methods are consid ered for IBDFE: one is HDIBDFE, and the oth er is SDIBDFE. In this paper, the first one is a dopted. In this scheme, 展开更多
关键词 underwater acoustic system single carrier IBDFE
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Nonlinear Coupled Analysis of a Single Point Mooring System 被引量:2
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作者 WANG Junrong LI Huajun LI Ping ZHOU Kai 《Journal of Ocean University of China》 SCIE CAS 2007年第3期310-314,共5页
Coupled effects on a single point mooring(SPM) system subjected to the combined action of wind,waves and current are studied in this paper. Due to the complicatedness of the sea state and the huge size of the vessel,p... Coupled effects on a single point mooring(SPM) system subjected to the combined action of wind,waves and current are studied in this paper. Due to the complicatedness of the sea state and the huge size of the vessel,physical experimental study is both time consuming and uneconomical,whereas the numerical study is cost-effective and DNV software provides powerful SESAM software in solving the issues. This paper focuses on the modeling process of the SPM system,catenary equilibrium calculation,static analysis of the vessel in three different scenarios,and dynamic response simulation of the SPM system under environmental excitations. The three scenarios in study are as follows:the SPM is under the combined function of(a) wind,waves and current,(b) wind and waves,(c) current and waves. They are so set that one can compare the contributions of different types of loads in both static and dynamic studies. Numerical study shows that wind and current are the two major factors contributing to the mooring line tension,and surge and sway are the two dominant motions of the moored vessel subjected to environmental excitations. 展开更多
关键词 single point mooring system response amplitude operator catenary equilibrium static analysis dynamic response
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Experimental and Numerical Investigations of Single Drop Mass Transfer in Solvent Extraction Systems with Resistance in Both Phases 被引量:2
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作者 李天文 毛在砂 +1 位作者 陈家镛 费维扬 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2002年第1期1-14,共14页
Numerical simulation of transient mass transfer to a single dropcontrolled by the internal resistance or by the resistance in bothphases was mathematically formulated and simulated in aboundary-fitted orthogonal coord... Numerical simulation of transient mass transfer to a single dropcontrolled by the internal resistance or by the resistance in bothphases was mathematically formulated and simulated in aboundary-fitted orthogonal coordinate system. The simulated resultson the transient mass transfer dominated by the internal resistanceare in good agreement with the Newman and Kronig-Brink models fordrops with low Reynolds number. When the drop Reynolds number is upto 200, the mass transfer coefficient from numerical simulation isvery low as compared with The Handlos-Baron model. 展开更多
关键词 solvent extraction single drop numerical simulation mass transferexperiment
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Investigation of single event effect in 28-nm system-on-chip with multi patterns 被引量:2
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作者 Wei-Tao Yang Yong-Hong Li +8 位作者 Ya-Xin Guo Hao-Yu Zhao Yang Li Pei Li Chao-Hui He Gang Guo Jie Liu Sheng-Sheng Yang Heng An 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第10期573-577,共5页
Single event effects (SEEs) in a 28-nm system-on-chip (SoC) were assessed using heavy ion irradiations, and susceptibilities in different processor configurations with data accessing patterns were investigated. The pa... Single event effects (SEEs) in a 28-nm system-on-chip (SoC) were assessed using heavy ion irradiations, and susceptibilities in different processor configurations with data accessing patterns were investigated. The patterns included the sole processor (SP) and asymmetric multiprocessing (AMP) patterns with static and dynamic data accessing. Single event upset (SEU) cross sections in static accessing can be more than twice as high as those of the dynamic accessing, and processor configuration pattern is not a critical factor for the SEU cross sections. Cross section interval of upset events was evaluated and the soft error rates in aerospace environment were predicted for the SoC. The tests also indicated that ultra-high linear energy transfer (LET) particle can cause exception currents in the 28-nm SoC, and some even are lower than the normal case. 展开更多
关键词 system-ON-CHIP heavy ion single event effect
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A Single Folded Beam Magneto-Optical Trap System for Neutral Mercury Atoms 被引量:1
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作者 刘亢亢 赵儒臣 +6 位作者 苟维 付小虎 刘洪力 尹士奇 孙剑芳 徐震 王育竹 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第7期38-41,共4页
Mercury is a promising candidate for the optical lattice clock, due to its low sensitivity to the blackbody radiation. We develop a single folded beam magneto-optical trap for the neutral mercury optical lattice clock... Mercury is a promising candidate for the optical lattice clock, due to its low sensitivity to the blackbody radiation. We develop a single folded beam magneto-optical trap for the neutral mercury optical lattice clock, with a 253. 7nm frequency quadrupled laser. Up to 1.7 × 10^6 (202Hg) or 1.5 × 10^6 (199Hg) atoms can be captured, and the atom temperature is lowered to 170μK (202Hg) or 50μK (199Hg). The cold atom signals of all six rich abundant isotopes are observed in this system. 展开更多
关键词 for of Hg A single Folded Beam Magneto-Optical Trap system for Neutral Mercury Atoms in is MOT
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Single incision laparoscopic fundoplication: A systematic review of the literature 被引量:1
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作者 Konstantinos Perivoliotis Chamaidi Sarakatsianou +1 位作者 Konstantinos Tepetes Ioannis Baloyiannis 《World Journal of Gastrointestinal Surgery》 SCIE CAS 2019年第3期179-190,共12页
BACKGROUND Fundoplication, was first introduced as a surgical treatment method of gastroesophageal reflux disease. Consequently, several modifications of this method have been described, whereas laparoscopic fundoplic... BACKGROUND Fundoplication, was first introduced as a surgical treatment method of gastroesophageal reflux disease. Consequently, several modifications of this method have been described, whereas laparoscopic fundoplication was recently introduced. Although single incision(SI) fundoplication was considered as an alternative to the conventional laparoscopic approach, several studies reported an increased operation duration, and high rates of multiport conversion and incisional hernia.AIM To provide a current overview of the technical variations and the postoperative outcomes of patients submitted to SI fundoplication.METHODS The present systematic review of the literature was designed and conducted on the basis of the PRISMA guidelines. A systematic screening of the electronic scholar databases(Medline, Scopus and Web of Science) was performed.RESULTS Literature search resulted in the identification of 19 studies. Overall, 266, 137 and110 SI Nissen, Dor and Toupet fundoplications were reported, respectively. In the majority of the trials, standard laparoscopic instruments were used. The left liver lobe was displayed through the use of forceps, graspers, retractors, drains or even glue. Both intra-corporeal and extracorporeal suturing was described. Mean operative time was 136.3 min. Overall complication rate was 5.2% and the rate of incisional hernia was 0.9%. No mortality was reported.CONCLUSIONDue to the methodological heterogeneity and the lack of high quality studies comparing multi to single access techniques and the several variations, we conclude that further well designed studies are necessary, in order to evaluate the role of SI fundoplication. 展开更多
关键词 single INCISION single PORT FUNDOPLICATION NISSEN Dor TOUPET
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A Single Mooring System with Sag-Extensibility and Flexural Rigidity Applied to Offshore Platform 被引量:1
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作者 M.-C. Tsai Hsien Hua Lee +1 位作者 Jun-Yen Lee S.-S. Hsiao 《China Ocean Engineering》 SCIE EI CSCD 2013年第3期335-350,共16页
Floating platform system has been extensively used in ocean exploitation, particularly for a tension-leg platform (TLP) system in deep water. Most of the TLPs are multi-mooring systems, where multi-joints are connec... Floating platform system has been extensively used in ocean exploitation, particularly for a tension-leg platform (TLP) system in deep water. Most of the TLPs are multi-mooring systems, where multi-joints are connected to the tension-legs so that the platform is not allowed to twist freely and may subject to enormous force induced by large incident waves in the weak-direction of the structure. This study aims to exploit a single moored offshore platform system that may attract less force and can be operated with less effort. In our analysis, in addition to mechanical properties of the tether, two important properties are also taken into consideration for the single mooring tether with expanded cross sectional dimension and utilization of stronger material, namely, the sag-extensibility and the flexural rigidity. Finally, the dynamic structural behavior produced by the mechanical effects on the new system is investigated and compared with that of traditional design while the wave-structure interactions of large body are also accounted for. Our study finds that the neglect of sag-extensibility or the flexural rigidity of large, strong mooring cable may result in a conservative but not necessarily safe design. 展开更多
关键词 tention leg platform (TLP) single mooring platform system flexural rigidity sag extensibility wave-structure interactions
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Application of Single Neuron Adaptive PID Regulators with Auto-tuning Gain in Industrial Parameter(Pressure)Closed-loop Process Control Systems 被引量:1
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作者 Shaoyuan Sun Huade Li +1 位作者 Bin Qian Jianping Wei(Information Engineering School, University of Science and Technology Beijing, Beijing 100083, China) 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 1999年第2期152-153,共2页
A type of single neuron adaptive PID regulator with auto-tuning gain is proposed and applied to the work control of fans, waterpumps and air-pressers etc. in Handan Iron & Steel Compel China. The robusthess of ind... A type of single neuron adaptive PID regulator with auto-tuning gain is proposed and applied to the work control of fans, waterpumps and air-pressers etc. in Handan Iron & Steel Compel China. The robusthess of induStrial parameter closed-loop process controlsystems is improved, and the work quality of the systems bettered. 展开更多
关键词 single neuron GAIN adaptiVe PID regulator pressure closed-loop control
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PET image reconstruction with a system matrix containing point spread function derived from single photon incidence response 被引量:1
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作者 樊馨 王海鹏 +8 位作者 贠明凯 孙校丽 曹学香 刘双全 柴培 李道武 刘宝东 王璐 魏龙 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第1期542-550,共9页
A point spread function(PSF) for the blurring component in positron emission tomography(PET) is studied. The PSF matrix is derived from the single photon incidence response function. A statistical iterative recons... A point spread function(PSF) for the blurring component in positron emission tomography(PET) is studied. The PSF matrix is derived from the single photon incidence response function. A statistical iterative reconstruction(IR) method based on the system matrix containing the PSF is developed. More specifically, the gamma photon incidence upon a crystal array is simulated by Monte Carlo(MC) simulation, and then the single photon incidence response functions are calculated. Subsequently, the single photon incidence response functions are used to compute the coincidence blurring factor according to the physical process of PET coincidence detection. Through weighting the ordinary system matrix response by the coincidence blurring factors, the IR system matrix containing the PSF is finally established. By using this system matrix, the image is reconstructed by an ordered subset expectation maximization(OSEM) algorithm. The experimental results show that the proposed system matrix can substantially improve the image radial resolution, contrast,and noise property. Furthermore, the simulated single gamma-ray incidence response function depends only on the crystal configuration, so the method could be extended to any PET scanner with the same detector crystal configuration. 展开更多
关键词 point spread function single photon incidence system matrix positron emission tomography
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An Adaptive Single Neural Control for Variable Step-Size P&O MPPT of Marine Current Turbine System 被引量:1
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作者 LI Ming-zhu WANG Tian-zhen +1 位作者 ZHOU Fu-na SHI Ming 《China Ocean Engineering》 SCIE EI CSCD 2021年第5期750-758,共9页
Marine current energy has been increasingly used because of its predictable higher power potential.Owing to the external disturbances of various flow velocity and the high nonlinear effects on the marine current turbi... Marine current energy has been increasingly used because of its predictable higher power potential.Owing to the external disturbances of various flow velocity and the high nonlinear effects on the marine current turbine(MCT)system,the nonlinear controllers which rely on precise mathematical models show poor performance under a high level of parameters’uncertainties.This paper proposes an adaptive single neural control(ASNC)strategy for variable step-size perturb and observe(P&O)maximum power point tracking(MPPT)control.Firstly,to automatically update the neuron weights of SNC for the nonlinear systems,an adaptive mechanism is proposed to adaptively adjust the weighting and learning coefficients.Secondly,aiming to generate the exact reference speed for ASNC to extract the maximum power,a variable step-size law based on speed increment is designed to strike a balance between tracking speed and accuracy of P&O MPPT.The robust stability of the MCT control system is guaranteed by the Lyapunov theorem.Comparative simulation results show that this strategy has favorable adaptive performance under variable velocity conditions,and the MCT system operates at maximum power point steadily. 展开更多
关键词 marine current turbine system perturb and observe single neural control adaptive mechanism maximum power point tracking
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