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A super-resolution algorithm for synthetic aperture radar based on modified spatially variant apodization

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Science China(Physics,Mechanics & Astronomy) 2011年第2期54卷 355-364页

作者： ni chong WANG YanFei XU XiangHui ZHOU ChangYi CUI PengFei Institute of Electronics Chinese Academy of SciencesBeijing 100190 China Graduate University of the Chinese Academy of Sciences Beijing 100190 China

The existing spatially variant apodizations(SVAs) either cannot depress the sidelobes effectively or reduce the energy of the *** improve this,a modified SVA(MSVA) is put forward in this paper,which expands the traditional filter from 3-taps to 5-taps and sets relevant parameters according to different sampling rates to get the excellent result that satisfies constrained optimization theory.A modified super-SVA is also presented,which compares the result after the iteration with the original signal and makes the one whose amplitude is smaller as the initial value of the next *** method can eliminate the sidelobes produced by the intermediate operation,so that the following bandwidth extrapolation is more ***-MSVA is presented based on the modified SVA and modified super-SVA,which is suitable for any Nyquist sampling rate,can extrapolate the signal bandwidth many times through iteration with a commensurate improvement in resolution,as demonstrated by the result of the experiment.

关键词： synthetic aperture radar sidelobe suppression super-resolution SVA

HULL GESTURE AND RESISTANCE PREDICTION OF HIGH-SPEED VESSELS

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Journal of Hydrodynamics 2011年第2期23卷 234-240页

作者： ni chong-ben ZHU Ren-chuan MIAO Guo-ping FAN Ju School of Naval Architecture Ocean and Civil Engineering State Key Laboratory of Ocean Engineering Shanghai Jiao Tong University Shanghai 200240 China

Since trim and sinkage are significant while vessels are advancing forward with high speed, the predicted vessel resistance based on restrained model theory or experiment may not be real resistance of vessels during voyage. It is necessary to take the influence of hull gesture into account for oredicting the resistance of high-speed ship. In the present work the resistance problem of high speed ship is treated with the viscous flow theory, and the dynamic mesh technique is adopted to coincide with variation of hull gesture of high speed vessel on voyage. The simulation of the models of S60 ship and a trimaran moving in towing tank with high speed are conducted by using the above theory and technique. The corresponding numerical results are in good agreement with the experimental data. It indicates that the resistance prediction for high speed vessels should take hull gesture into consideration and the dynamic mesh method proposed here is effective in calculating the resistance of high speed vessels.

关键词： ship trim and sinkage dynamic mesh high-speed vessel resistance

Path Planning Method Based on D^(*) lite Algorithm for Unmanned Surface Vehicles in Complex Environments

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China Ocean Engineering 2021年第3期35卷 372-383页

作者： YAO Yan-long LIANG Xiao-feng LI Ming-zhi YU Kai CHEN Zhe ni chong-ben TENG Yue State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai 200240China Key Laboratory of Marine Intelligent Equipment and System of Ministry of Education Shanghai Jiao Tong UniversityShanghai 200240China Joint Institute Shanghai Jiao Tong UniversityShanghai 200240China

In recent decades,path planning for unmanned surface vehicles(USVs)in complex environments,such as harbours and coastlines,has become an important *** existing algorithms for real-time path planning for USVs are either too slow at replanning or unreliable in changing environments with multiple dynamic *** this study,we developed a novel path planning method based on the D^(*) lite algorithm for real-time path planning of USVs in complex *** proposed method has the following advantages:(1)the computational time for replanning is reduced significantly owing to the use of an incremental algorithm and a new method for modelling dynamic obstacles;(2)a constrained artificial potential field method is employed to enhance the safety of the planned paths;and(3)the method is practical in terms of vehicle *** performance of the proposed method was evaluated through simulations and compared with those of existing *** simulation results confirmed the efficiency of the method for real-time path planning of USVs in complex environments.

关键词： path planning unmanned surface vehicle D^(*)lite algorithm complex environment

Multisensor Remote Sensing Imagery Super-Resolution with Conditional GAN

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Journal of Remote Sensing 2021年第1期2021卷 262-272页

作者： Junwei Wang Kun Gao Zhenzhou Zhang chong ni Zibo Hu Dayu Chen Qiong Wu Key Laboratory of Photoelectronic Imaging Technology and System Ministry of EducationBeijing Institute of TechnologyBeijing 100081China Institute of Spacecraft System Engineering CASTBeijing 100094China

Despite the promising performance on benchmark datasets that deep convolutional neural networks have exhibited in single image super-resolution(SISR),there are two underlying limitations to existing ***,current supervised learningbased SISR methods for remote sensing satellite imagery do not use paired real sensor data,instead operating on simulated high-resolution(HR)and low-resolution(LR)image-pairs(typically HR images with their bicubic-degraded LR counterparts),which often yield poor performance on real-world LR ***,SISR is an ill-posed problem,and the super-resolved image from discriminatively trained networks with l p norm loss is an average of the infinite possible HR images,thus,always has low perceptual *** this issue can be mitigated by generative adversarial network(GAN),it is still hard to search in the whole solution-space and find the best *** this paper,we focus on real-world application and introduce a new multisensor dataset for real-world remote sensing satellite imagery *** addition,we propose a novel conditional GAN scheme for SISR task which can further reduce the ***,the super-resolved images have not only high fidelity,but high perceptual quality as *** experiments demonstrate that networks trained on the introduced dataset can obtain better performances than those trained on simulated ***,the proposed conditional GAN scheme can achieve better perceptual quality while obtaining comparable fidelity over the state-of-the-art methods.

关键词： networks image resolution

Development of the electric automatic steering system for agricultural vehicles

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International Journal of Agricultural and Biological Engineering 2024年第1期17卷 209-214页

作者： Guangshun An chong Yu Juan Du Xiang Yin Youliang ni Chengqian Jin School of Agricultural Engineering and Food Science Shandong University of TechnologyZibo 255000ShandongChina Nanjing Research Institute for Agricultural Mechanization of Ministry of Agriculture and Rural Affairs Nanjing 210014China

Automatic guidance of agricultural vehicles requires automatic execution of operation commands received from the navigation controller by using electronically controlled mechanisms for wheel steering,speed changing and work *** steering contributes as a prerequisite technique in automatic and semi-automatic agricultural *** research aimed to develop an electric automatic steering system that was compact in its structure and integrated into original steering mechanism in a simply and convenient way for aftermarket modification.A brushless motor and reducer assembly was utilized to provide an adequate steering torque instead of manual maneuver.A rapid assembling approach was proposed by passing the steering shaft through the hollow output shaft.A digital proportional-integral-differential(PID)algorithm was implemented to calculate the rotation speeds and directions by comparing the desired angle and the actual angle,which was implemented in a printed circuit board with a microcontroller unit(MCU)and interface *** unmanned wheeled tractor was applied as test platform to integrate the newly developed electric automatic steering *** were conducted to evaluate its performance in terms of stability and *** autonomous navigation system guided the tractor along target paths in the field by sending steering commands to the electric automatic steering *** results show that the steering angle error was less than 0.81°when desired steering angle was less than 10°.The lateral error difference was no more than 4.76 cm when repeating following the same target path,which indicated that the electric automatic steering system responded accurately and robustly to steering commands.

关键词： automatic steering automatic navigation agricultural vehicles

Is laparoscopy equal to laparotomy in detecting and treating small bowel injuries in a porcine model?

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World Journal of Gastroenterology 2012年第46期18卷 6850-6855页

作者： Cheng-Xiang Shan chong ni Ming Qiu Dao-Zhen Jiang Department of General Surgery Chang Zheng Hospital Affiliated to the Second Military Medical University

AIM: To evaluate the safety and effectiveness of laparoscopy compared with laparotomy for diagnosing and treating small bowel injuries (SBIs) in a porcine model. METHODS: Twenty-eight female pigs were anesthetized and laid in the left recumbent position. The SBI model was established by shooting at the right lower quadrant of the abdomen. The pigs were then randomized into either the laparotomy group or the laparoscopy group. All pigs underwent routine exploratory laparotomy or laparoscopy to evaluate the abdominal injuries, particularly the types, sites, and numbers of SBIs. Traditional open surgery or therapeutic laparoscopy was then performed. All pigs were kept alive within the observational period (postoperative 72 h). The postoperative recovery of each pig was carefully observed. RESULTS: The vital signs of all pigs were stable within 1-2 h after shooting and none of the pigs died from gunshot wounds or SBIs immediately. The SBI model was successfully established in all pigs and definitively diagnosed with single or multiple SBIs either by exploratory laparotomy or laparoscopy. Compared with exploratory laparotomy, laparoscopy took a significantly longer time for diagnosis (41.27 ± 12.04 min vs 27.64 ± 13.32 min, P = 0.02), but the time for therapeutic laparoscopy was similar to that of open surgery. The length of incision was significantly reduced in the laparoscopy group compared with the laparotomy group (5.27 ± 1.86 cm vs 15.73 ± 1.06 cm, P nitive diagnosis with no missed injuries. Postoperative complications occurred in four cases (three following laparotomy and one following laparoscopy, P = 0.326). The average recovery period for bowel function, vital appearance, and food re-intake after laparoscopy was 10.36 ± 4.72 h, 14.91 ± 3.14 h, and 15.00 ± 7.11 h, respectively. All of these were significantly shorter than after laparotomy (21.27 ± 10.17

关键词： Laparoscopy Laparotomy Small bowel injury Porcine model Diagnosis Treatment Penetrating injury Firearm injury

Sensitive humidity sensor based on moisture-driven energy generation

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Nano Research 2024年第6期17卷 5578-5586页

作者： Qingchao ni Qing Lou Chenglong Shen Guangsong Zheng Runwei Song Jingnan Hao Jialu Liu Jinyang Zhu Jinhao Zang Lin Dong chong-Xin Shan Henan Key Laboratory of Diamond Optoelectronic Materials and Devices Key Laboratory of Materials PhysicsMinistry of Educationand School of Physics and MicroelectronicsZhengzhou UniversityZhengzhou 450052China State Centre for International Cooperation on Designer Low-Carbon&Environmental Materials and School of Materials Science and EngineeringZhengzhou UniversityZhengzhou 450001China

The emergence of novel self-powered humidity sensors has attracted considerable attention in the fields of smart electronic devices and personal ***,self-powered humidity sensors have been fabricated using a moisture-driven energy generation(MEG)device based on asymmetric tubular graphitic carbon nitride(g-CN)films prepared on anodized aluminum(AAO)*** a relative humidity(RH)of 96%,the MEG device can provide an open-circuit voltage of 0.47 V and a short-circuit current of 3.51μA,with a maximum output power of 0.08μ*** inherent self-powered ability and humidity response via current variation,an extraordinary response of 1.78×106%(41%-96%RH)can be gained from the MEG *** possible power generation mechanism is that g-CN/AAO heterostructure can form ion gradient and diffusion under the action of moisture to convert chemical potential into electrical potential,evoking a connaturally sensitive response to ***-powered respiration monitoring device based on the sensor is designed to monitor human movement(sitting,warming up,and running)and sleep status(normal,snoring,and apnea),maintaining excellent stability during cumulative 12-h respiration *** self-powered humidity sensing technology has promising potential for extensive integration into smart electronic and round-the-clock health monitoring devices.

关键词： graphitic carbon nitride moisture-driven energy generation humidity sensor respiration monitoring

Research of Final EMS for Bloom in Ansteel

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Journal of Iron and Steel Research International 2012年第S2期19卷 892-895页

作者： GUO Qing-tao JIN Bai-gang LUO Jian-hua ni chong-yi WAN Xue-feng LIAO Xiang-wei Technology Center of Angang Steel Co. Ltd. Bayuquan Iron and Steel Subsidiary of Angang Steel Co. Ltd. Steel Company of Angang Steel Co. Ltd.

In this paper,the best final EMS frequency for bloom continuous casting is *** 280×380 bloom,the best frequency is in the range of 4;*** results also show that,with this frequency,the electromagnetic force in the molten steel in the bloom reaches stronger and the electromechanical transformation rate of the stirring equipment is *** flow fields in the bloom with the various stirring parameters are simulated *** final EMS parameters for bloom are optimized base on the simulation *** experimental results show that,for high carbon steel,the best stirring frequency is 7 Hz and the current is *** order to alleviate negative segregation of the low and medium carbon steel,the stirring frequency and the current should be 4Hz and 430A,respectively.

关键词： final EMS stirring frequency shrinkage cavity

多分辨重叠变换在扩频通信系统抗干扰中的应用

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电子学报 2000年第4期28卷 17-19页

作者：李冲泥胡光锐上海交通大学电子信息学院上海200030

本文利用多分辨重叠变换 (HLT)把接收机信号映射到变换域进行抗干扰处理 .与重叠变换 (LT)不同 ,HLT对信号频谱的非均匀划分可以有效地把干扰能量集中在有限的变换域子带 (TransformBins)中 ,因此对抑制随机脉冲干扰非常有效 .与小波变... 详细信息

本文利用多分辨重叠变换 (HLT)把接收机信号映射到变换域进行抗干扰处理 .与重叠变换 (LT)不同 ,HLT对信号频谱的非均匀划分可以有效地把干扰能量集中在有限的变换域子带 (TransformBins)中 ,因此对抑制随机脉冲干扰非常有效 .与小波变换 (WT)相比 ,HLT对信号频谱的划分更加灵活 .由于可以使用基于重叠变换的快速算法 ,在滤波性能相当的情况下 ,HLT比小波变换节省计算量 .仿真结果表明 ,其于HLT的变换域处理方案可以有效地抑制非时变窄带干扰和时变宽带干扰 ,明显地改善系统性能 .

关键词：多分辨重叠变换扩频通信系统抗干扰