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A Novel Fractional Dengue Transmission Model in the Presence of Wolbachia Using Stochastic Based Artificial Neural Network
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作者 Zeshan Faiz Iftikhar Ahmed +1 位作者 Dumitru Baleanu Shumaila Javeed 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第5期1217-1238,共22页
The purpose of this research work is to investigate the numerical solutions of the fractional dengue transmission model(FDTM)in the presence of Wolbachia using the stochastic-based Levenberg-Marquardt neural network(L... The purpose of this research work is to investigate the numerical solutions of the fractional dengue transmission model(FDTM)in the presence of Wolbachia using the stochastic-based Levenberg-Marquardt neural network(LM-NN)technique.The fractional dengue transmission model(FDTM)consists of 12 compartments.The human population is divided into four compartments;susceptible humans(S_(h)),exposed humans(E_(h)),infectious humans(I_(h)),and recovered humans(R_(h)).Wolbachia-infected and Wolbachia-uninfected mosquito population is also divided into four compartments:aquatic(eggs,larvae,pupae),susceptible,exposed,and infectious.We investigated three different cases of vertical transmission probability(η),namely when Wolbachia-free mosquitoes persist only(η=0.6),when both types of mosquitoes persist(η=0.8),and when Wolbachia-carrying mosquitoes persist only(η=1).The objective of this study is to investigate the effectiveness of Wolbachia in reducing dengue and presenting the numerical results by using the stochastic structure LM-NN approach with 10 hidden layers of neurons for three different cases of the fractional order derivatives(α=0.4,0.6,0.8).LM-NN approach includes a training,validation,and testing procedure to minimize the mean square error(MSE)values using the reference dataset(obtained by solving the model using the Adams-Bashforth-Moulton method(ABM).The distribution of data is 80% data for training,10% for validation,and,10% for testing purpose)results.A comprehensive investigation is accessible to observe the competence,precision,capacity,and efficiency of the suggested LM-NN approach by executing the MSE,state transitions findings,and regression analysis.The effectiveness of the LM-NN approach for solving the FDTM is demonstrated by the overlap of the findings with trustworthy measures,which achieves a precision of up to 10^(-4). 展开更多
关键词 WOLBACHIA DENGUE neural network vertical transmission mean square error LEVENBERG-MARQUARDT
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Automatic Scallion Seedling Feeding Mechanism with an Asymmetrical High-order Transmission Gear Train 被引量:3
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作者 Xiong Zhao Jun Ye +2 位作者 Mengyan Chu Li Dai Jianneng Chen 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2020年第1期148-161,共14页
The current automatic scallion-transplanting machine is a complicated mechanism composed of two linkage mechanisms and two band carriers.It delivers seedlings ine ciently because of the movement limitations of the lin... The current automatic scallion-transplanting machine is a complicated mechanism composed of two linkage mechanisms and two band carriers.It delivers seedlings ine ciently because of the movement limitations of the linkage mechanism.This paper proposes a new high-order non-circular gear train for an automatic scallion-seedling feeding mechanism.The proposed gear train has an asymmetrical transmission ratio;i.e.,its transmission ratio varies.This allows the mechanism’s execution component to move in a long displacement and rotate in a large rotation angle.The long displacement enables the execution component to reach the designed working position,and the large rotation angle allows it to feed a scallion in the required pose.A mathematical model for calculating the asymmetrical transmission ratio was established according to the closure requirements and the full-cycle motion of the driven gear pitch curve.Then,the parameter-design model of the new seedling-feeding mechanism was established,based on precise pose points and trajectory-shape control points.Moreover,an aided-design program was developed to obtain the parameter-solution domain of the scallion-seedling feeding mechanism.The mechanism parameters,which met the seedling-feeding function,were optimized to determine the transmission ratio,using a program and a kinematic simulation.Finally,a prototype of the mechanism was produced,and a seedling-feeding experiment was carried out.One-thousand seedlings were tested at a rate of 100 seedlings per minute,and the statistical success rate was 93.4%.Thus,the automatic scallion-seedling feeding mechanism significantly improves the e ciency of automatically transplanting scallions. 展开更多
关键词 Asymmetric transmission Scallion TRANSPLANTING high-order GEAR NON-CIRCULAR GEAR Planetary GEAR train
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Joint resource allocation for MIMO-OFDM video transmission systems with unequal error protection 被引量:3
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作者 张成文 刘鑫 谭学治 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2012年第2期119-124,共6页
To improve the performance of MIMO-OFDM video transmission systems on the limitation of wireless bandwidth and transmitting power,we propose an adaptive joint resource allocation algorithm with unequal error protectio... To improve the performance of MIMO-OFDM video transmission systems on the limitation of wireless bandwidth and transmitting power,we propose an adaptive joint resource allocation algorithm with unequal error protection(UEP) based on joint source-channel coding(JSCC) according to H.264 video compression standard and RCPT channel coding.According to different thresholds of the average SNR of subchannels,the algorithm dynamically allocates the source coding parameters of original video data and the channel coding parameters of RCPT,which realizes UEP for the compressed video data of different importance.Through the bit and power allocation based on MQAM modulation and the subspace allocation based on beamforming technology for different subcarriers,an adaptive joint resource allocation making full use of space-frequency domain resources have been realized.The simulation results indicate that the algorithm improves the adaptability of video transmission systems in different wireless environments and the quality of video retrieval. 展开更多
关键词 video transmission MIMO-OFDM unequal error protection joint source-channel coding
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Effect of static transmission error on dynamic responses of spiral bevel gears 被引量:3
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作者 唐进元 胡泽华 +1 位作者 吴丽娟 陈思雨 《Journal of Central South University》 SCIE EI CAS 2013年第3期640-647,共8页
The effect of static transmission error on nonlinear dynamic response of the spiral bevel gear system combining with time-varying stiffness and backlash was investigated.Firstly,two different control equations of the ... The effect of static transmission error on nonlinear dynamic response of the spiral bevel gear system combining with time-varying stiffness and backlash was investigated.Firstly,two different control equations of the spiral bevel gear model were adopted,where the static transmission error was expressed in two patterns as predesigned parabolic function and sine function of transmission errors.The dynamic response,bifurcation map,time domain response,phase curve and Poincare map were obtained by applying the explicit Runge-Kutta integration routine with variable-step.A comparative study was carried out and some profound phenomena were detected.The results show that there are many different kinds of tooth rattling phenomena at low speed.With the increase of speed,the system enters into stable motion without any rattling in the region(0.72,1.64),which indicates that the system with predesigned parabolic function of transmission error has preferable capability at high speed. 展开更多
关键词 螺旋锥齿轮 传输误差 动态响应 静态 POINCARE映射 非线性动力响应 抛物线函数 齿轮系统
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A METHOD OF ANALYSIS OF MACHINE TOOL TRANSMISSION CHAIN ERROR
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作者 宋建农 李虹 蔡康洪 《Journal of China Textile University(English Edition)》 EI CAS 1991年第2期34-42,共9页
The indexing transmission chain error of gear cutting machines is an obviously periodic timefunction. If data are acquired properly while surveying and analyzing the error with grating typeinstrument attached to a mic... The indexing transmission chain error of gear cutting machines is an obviously periodic timefunction. If data are acquired properly while surveying and analyzing the error with grating typeinstrument attached to a micro-computer, the analysis will be easier and quicker. In this paper,such a system is introduced; a data acquiring interface is designed. Therefore, real-time samplingcan be performed. The results obtained from the indexing tramsmission chain error of several gearhobbing and shaping machines with this system were satisfactory. 展开更多
关键词 DATA porcessing sampling INDEXING errorS transmission CHAIN
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A METHOD FOR THE MEASUREMENT OF DYNAMIC TRANSMISSION ERROR OF PRECISION HOBBING MACHINES
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作者 黄迪山 童忠钫 陆乃炎 《Journal of China Textile University(English Edition)》 EI CAS 1991年第4期59-64,共6页
In the paper,a new method for the measurement of the dynamic transmission crror of preci-sion hobbing machines using only one sensor is proposed.The dynamic transmission error i ob-tained by demodulating the phase-mod... In the paper,a new method for the measurement of the dynamic transmission crror of preci-sion hobbing machines using only one sensor is proposed.The dynamic transmission error i ob-tained by demodulating the phase-modulated signal according to the Hilbert transform priple.The results of dynamic testing show that the new method is effective. 展开更多
关键词 HILBERT TRANSFORM measurement DYNAMIC transmission error
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Excitation Prediction by Dynamic Transmission Error under Sliding Friction in Helical Gear System 被引量:1
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作者 李文良 王黎钦 常山 《Transactions of Tianjin University》 EI CAS 2013年第6期448-453,共6页
Monte Carlo method was adopted to calculate the meshing error considering the manufacture error and assembly error of the meshing point along the time-varying contact line for helical gear pair. The flexural-torsion-a... Monte Carlo method was adopted to calculate the meshing error considering the manufacture error and assembly error of the meshing point along the time-varying contact line for helical gear pair. The flexural-torsion-axis dynamic model coupled was established under the tooth friction force and solved by the perturbation method to compute real dynamic tooth load. The change laws of the friction force and friction torque were obtained in a meshing period. The transmission error formulation was analyzed to introduce meshing excitations. The maximum dynamic transmission error, the maximum meshing force and the maximum dynamic factor were calculated under different speeds, external loads and damping factors. The conclusions can provide theoretical basis for the gear design especially in tooth profile correction. 展开更多
关键词 传动误差 滑动摩擦 齿轮系统 预测 激发 蒙特卡洛方法 摩擦力矩 动力学模型
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Information loss recovery for JPEG2000 image transmission in an error-prone environment
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作者 刘洁瑜 张德运 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2008年第3期430-435,共6页
Information loss recovery techniques are important for transmitting images over error-prone channels at the decoder. A novel error recovery scheme for JPEG2000 image is presented in this paper, which adopts different ... Information loss recovery techniques are important for transmitting images over error-prone channels at the decoder. A novel error recovery scheme for JPEG2000 image is presented in this paper, which adopts different techniques for the lowest frequency coefficients and high frequency coefficients in the wavelet domain. The low-frequency recovery algorithm was implemented by adopting the watermarking technique and the packet structure of JPEG2000. The low-frequency coefficients taken as the hidden data were extracted from the compressed bit stream, and then were embedded back into the bit stream itself prior to transmission. The embedded data were used to recover the information loss. High-frequency reconstruction was performed in bitplane base. The damaged bitplanes were recovered according to the correlation in the wavelet subband structure and by using the algorithm based on the horizontal and vertical edge detection. Experiments verified the effectiveness of these algorithms. 展开更多
关键词 信息损失 信息处理 图象传输 错误校正 JPEG2000
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Designing the Instrument Crank-Coupler Mechanism of Linear Output with Least Transmission Ratio Error
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作者 裘建新 赵爱华 《Journal of Donghua University(English Edition)》 EI CAS 2004年第4期46-51,共6页
Movement accuracy is the key factor to be considered in designing precision instrument linkage and mini-linkage mechanisms. Although manufacturing errors, elastic deformation, kinematic pair clearance and friction fac... Movement accuracy is the key factor to be considered in designing precision instrument linkage and mini-linkage mechanisms. Although manufacturing errors, elastic deformation, kinematic pair clearance and friction factors all will have synthesis effect on the position accuracy of the mechanical system, the essential factor to guarantee the movement precision remains the kinematic dimensions. Combining the classical theory of mechanical synthesis with the modern error theory and the numerical method, the authors put forward a systematic and complete process and method of computer aided design for the instrument crank-coupler mechanism in which the follower takes the linear displacement approximately within a certain limited domain, with the design result of least transmission ratio error. 展开更多
关键词 曲柄连接机构 线性输出量 传动比 误差 计算机辅助设计
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DESIGN OF IRREGULAR LDPC CODE WITH UNEQUAL ERROR PROTECTION PROPERTY AND ITS PERFORMANCE ANALYSIS ON IMAGE TRANSMISSION
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作者 Wang Ruihua Yin Liuguo +1 位作者 Yu Quan Lu Jianhua 《Journal of Electronics(China)》 2005年第6期658-662,共5页
Based on the property that high degree variable nodes within an irregular LowDensity Parity-Check (LDPC) code have more powerful error-correcting capability than that of low degree variable nodes, a group of irregular... Based on the property that high degree variable nodes within an irregular LowDensity Parity-Check (LDPC) code have more powerful error-correcting capability than that of low degree variable nodes, a group of irregular LDPC codes with Unequal Error Protection (UEP)property is designed in this letter. Simulation results show that the transmission quality of the image may be effectively improved with this class of irregular LDPC code. 展开更多
关键词 LDPC 低密度奇偶检测码 误差分析 数据保护 图象传输
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Human Errors Monitoring in Electrical Transmission Networks
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作者 Gheorghe Grigoras Cecilia Barbulescu +1 位作者 Gheorghe Cartina Daniela Comanescu 《Journal of Energy and Power Engineering》 2012年第3期425-428,共4页
关键词 电力传输 人为错误 网络监测 复杂系统 传输网络 设备故障 电网公司 罗马尼亚
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NO REVERSE ERROR BALL TRANSMISSION AND FORCE ANALYSIS ON HETERO TYPE SINGLE CYCLOID
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作者 An Zijun Qu Zhigang ( Yanshan University) 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 1996年第1期1-5,共3页
The construction kinematics and no reverse error property of heterotype single cycloid steel ball transmission are studied and its engagement pairs structure as well as foree analysis are al- so presented. It pr... The construction kinematics and no reverse error property of heterotype single cycloid steel ball transmission are studied and its engagement pairs structure as well as foree analysis are al- so presented. It provides a kind of high property driver of large transmission ratio and compact con- struction and has theoretical and practical significance for application of the steel ball transmission. 展开更多
关键词 Heterotype cycloid Reverse error Steel ball transmission
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Design and Analysis of the Gemini Chain System in Dual Clutch Transmission of Automobile 被引量:3
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作者 CHENG Yabing GUO Haitao +3 位作者 FU Zhenming WAN Nen LI Lei WANG Yang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2015年第1期38-45,共8页
Chain drive system is widely used in the conditions of high-speed, overload, variable speed and load, Many studies are focused on the meshing theory and wear characteristics of chain drive system, but system design, a... Chain drive system is widely used in the conditions of high-speed, overload, variable speed and load, Many studies are focused on the meshing theory and wear characteristics of chain drive system, but system design, analysis, and noise characteristics of the chain drive system are weak. System design and noise characteristic are studied for a new type Gemini chain of dual-clutch automatic transmission. Based on the meshing theory of silent chain, the design parameters of the Gemini chain system are calculated and the mathematical models and dynamic analysis models of the Gemini chain system are established. Dynamic characteristics of the Gemini chain system is simulated and the contact force of plate and pin, plate and sprockets, the chain tension forces, the transmission error and the stress of plates and pins are analyzed. According to the simulation results of the Gemini chain system, the noise experiment about system is carried out. The noise values are tested at different speed and load and spectral characteristics are analyzed. The results of simulation and experimental show that the contact forces of plate and pin, plate and sprockets are smaller than the allowable stress values, the chain tension force is less than ultimate tension and transmission error is limited in 1.2%. The noise values can meet the requirements of industrial design, and it is proved that the design and analysis method of the Gemini chain system is scientific and feasible. The design and test system is built from analysis to test of Gemini chain system. This research presented will provide a corresponding theoretical guidance for the design and dynamic characteristics and noise characteristics of chain drive system. 展开更多
关键词 Gemini chain system design noise characteristic dynamic characteristic transmission error
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Mode Selection for CoMP Transmission with Nonideal Synchronization 被引量:1
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作者 Zheqi Gu Zhongpei Zhang 《China Communications》 SCIE CSCD 2018年第12期132-146,共15页
This paper proposes a mode selection scheme to improve the spectral efficiency for coordinated multi-point(CoMP) transmission with phase synchronization errors(PSE). Upper bounds of average achievable rate for differe... This paper proposes a mode selection scheme to improve the spectral efficiency for coordinated multi-point(CoMP) transmission with phase synchronization errors(PSE). Upper bounds of average achievable rate for different CoMP transmission modes, such as coordinated beamforming(CB) and joint processing(JP), are derived by random matrix theory and asymptotic mathematical approximation. According to these upper bounds, the proposed scheme switches CoMP transmission mode between CB and JP adaptively to enhance the average achievable rate. Simulation results show that these upper bounds agree well with the average achievable rates for both JP and CB, and the proposed scheme outperforms traditional single mode CoMP transmission when PSE exist. 展开更多
关键词 COMP transmission SYNCHRONIZATION errorS PRECODING mode SELECTION
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Research on Transmission Accuracy Characteristic Analysis of RV Reducer 被引量:7
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作者 TAN Peng QI Houjun +2 位作者 HAN Lin FENG Juntao MA Dongsheng 《International Journal of Plant Engineering and Management》 2019年第3期157-168,共12页
The accuracy of RV reducer transmission is mainly affected by the transmission accuracy. Taking the high precision RV-80E reducer as the research object, aiming at its structural characteristics, the rigid-flexible co... The accuracy of RV reducer transmission is mainly affected by the transmission accuracy. Taking the high precision RV-80E reducer as the research object, aiming at its structural characteristics, the rigid-flexible coupling model of RV reducer is established by using ADAMS multi-body dynamics simulation software, and the correctness of the model is verified. At the same time, the rigid-flexible coupling model is used to design several groups of simulation prototypes with different errors, and the influence of different error factors on the transmission accuracy of the whole machine is analyzed by simulation. Finally, through different error factors, it is concluded that the error combination of positive equidistance+negative offset or negative equidistance+positive offset can effectively reduce the influence of transmission error on the transmission accuracy of the whole machine. 展开更多
关键词 RV REDUCER rigid-flexible coupling transmission error transmission ACCURACY
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High-Order Local Discontinuous Galerkin Algorithm with Time Second-Order Schemes for the Two-Dimensional Nonlinear Fractional Diffusion Equation 被引量:1
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作者 Min Zhang Yang Liu Hong Li 《Communications on Applied Mathematics and Computation》 2020年第4期613-640,共28页
In this article,some high-order local discontinuous Galerkin(LDG)schemes based on some second-order θ approximation formulas in time are presented to solve a two-dimen-sional nonlinear fractional diffusion equation.T... In this article,some high-order local discontinuous Galerkin(LDG)schemes based on some second-order θ approximation formulas in time are presented to solve a two-dimen-sional nonlinear fractional diffusion equation.The unconditional stability of the LDG scheme is proved,and an a priori error estimate with O(h^(k+1)+At^(2))is derived,where k≥0 denotes the index of the basis function.Extensive numerical results with Q^(k)(k=0,1,2,3)elements are provided to confirm our theoretical results,which also show that the second-order convergence rate in time is not impacted by the changed parameter θ. 展开更多
关键词 Two-dimensional nonlinear fractional difusion equation high-order LDG method Second-orderθscheme Stability and error estimate
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SER analysis and power allocation for hybrid cooperative transmission system 被引量:2
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作者 Guoyan Li Youguang Zhang Wang Kang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2012年第5期661-670,共10页
The symbol-error-rate(SER) and power allocation for hybrid cooperative(HC) transmission system are investigated.Closed-form SER expression is derived by using the moment generating function(MGF)-based approach.H... The symbol-error-rate(SER) and power allocation for hybrid cooperative(HC) transmission system are investigated.Closed-form SER expression is derived by using the moment generating function(MGF)-based approach.However,the resultant SER contains an MGF of the harmonic mean of two independent random variables(RVs),which is not tractable in SER analysis.We present a simple MGF expression of the harmonic mean of two independent RVs which avoids the hypergeometric functions used commonly in previous studies.Using the simple MGF,closed-form SER for HC system with M-ary phase shift keying(M-PSK) signals is provided.Further,an approximation as well as an upper bound of the SER is presented.It is shown that the SER approximation is asymptotically tight.Based on the tight SER approximation,the power allocation of the HC system is investigated.It is shown that the optimal power allocation does not depend on the fading parameters of the source-destination(SD) channel and it only depends on the source-relay(SR) and relay-destination(RD) channels.Moreover,the performance gain of the power allocation depends on the ratio of the channel quality between RD and SR.With the increase of this ratio,more performance gain can be acquired. 展开更多
关键词 cooperative transmission relaying protocols hybrid cooperation symbol-error-rate(SER) power allocation
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Soliton fusion and fission for the high-order coupled nonlinear Schr?dinger system in fiber lasers
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作者 王天一 周勤 刘文军 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第2期250-254,共5页
With the rapid development of communication technology,optical fiber communication has become a key research area in communications.When there are two signals in the optical fiber,the transmission of them can be abstr... With the rapid development of communication technology,optical fiber communication has become a key research area in communications.When there are two signals in the optical fiber,the transmission of them can be abstracted as a high-order coupled nonlinear Schr¨odinger system.In this paper,by using the Hirota’s method,we construct the bilinear forms,and study the analytical solution of three solitons in the case of focusing interactions.In addition,by adjusting different wave numbers for phase control,we further discuss the influence of wave numbers on soliton transmissions.It is verified that wave numbers k_(11),k_(21),k_(31),k_(22),and k_(32)can control the fusion and fission of solitons.The results are beneficial to the study of all-optical switches and fiber lasers in nonlinear optics. 展开更多
关键词 SOLITON Hirota’s method high-order coupled nonlinear Schrodinger system soliton transmission
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Improved FEC Code Based on Concatenated Code for Optical Transmission Systems 被引量:1
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作者 YUAN Jian-guo JIANG Ze MAO You-ju 《Semiconductor Photonics and Technology》 CAS 2006年第3期211-216,共6页
关键词 光学传输系统 误差修正 连接码 框架结构
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Characterization of Blue-Green Light Non-Line-of-Sight Transmission in Seawater
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作者 Xizheng Ke Gang Li 《Optics and Photonics Journal》 CAS 2022年第11期234-252,共19页
The blue-green light in the 450 nm to 550 nm band is usually used in underwater wireless optical communication (UWOC). The blue-green light transmission in seawater is scattered by the seawater effect and can achieve ... The blue-green light in the 450 nm to 550 nm band is usually used in underwater wireless optical communication (UWOC). The blue-green light transmission in seawater is scattered by the seawater effect and can achieve communication in non-line-of-sight (NLOS) transmission mode. Compared to line-of-sight (LOS) transmission, NLOS transmission does not require alignment and can be adapted to various underwater environments. The scattering coefficients of seawater at different depths are different, which makes the scattering of light in different depths of seawater different. In this paper, the received optical power and bit error rate (BER) of the photodetector (PD) were calculated when the scattering coefficients of blue-green light in seawater vary from large to small with increasing depth for NLOS transmission. The results show that blue-green light in different depths of seawater in the same way NLOS communication at the same distance, the received optical power and BER at the receiver are different, and the received optical power of green light is greater than that of blue light. Increasing the forward scattering coverage of the laser will suppress the received optical power of the PD, so when performing NLOS communication, appropriate trade-offs should be made between the forward scattering coverage of the laser and the received optical power. 展开更多
关键词 Underwater Wireless Optical Communication Non-Line-of-Sight transmission Scattering Coefficient Received Optical Power Bit error Rate
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