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Intelligent field monitoring system for cruciferous vegetable pests using yellow sticky board images and an improved Cascade R-CNN
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作者 Yufan Gao Fei Yin +5 位作者 Chen Hong Xiangfu Chen Hang Deng Yongjian liu zhenyu li Qing Yao 《Journal of Integrative Agriculture》 2025年第1期220-234,共15页
Cruciferous vegetables are important edible vegetable crops.However,they are susceptible to various pests during their growth process,which requires real-time and accurate monitoring of these pests for pest forecastin... Cruciferous vegetables are important edible vegetable crops.However,they are susceptible to various pests during their growth process,which requires real-time and accurate monitoring of these pests for pest forecasting and scientific control.Hanging yellow sticky boards is a common way to monitor and trap those pests which are attracted to the yellow color.To achieve real-time,low-cost,intelligent monitoring of these vegetable pests on the boards,we established an intelligent monitoring system consisting of a smart camera,a web platform and a pest detection algorithm deployed on a server.After the operator sets the monitoring preset points and shooting time of the camera on the system platform,the camera in the field can automatically collect images of multiple yellow sticky boards at fixed places and times every day.The pests trapped on the yellow sticky boards in vegetable fields,Plutella xylostella,Phyllotreta striolata and flies,are very small and susceptible to deterioration and breakage,which increases the difficulty of model detection.To solve the problem of poor recognition due to the small size and breaking of the pest bodies,we propose an intelligent pest detection algorithm based on an improved Cascade R-CNN model for three important cruciferous crop pests.The algorithm uses an overlapping sliding window method,an improved Res2Net network as the backbone network,and a recursive feature pyramid network as the neck network.The results of field tests show that the algorithm achieves good detection results for the three target pests on the yellow sticky board images,with precision levels of 96.5,92.2 and 75.0%,and recall levels of 96.6,93.1 and 74.7%,respectively,and an F_(1) value of 0.880.Compared with other algorithms,our algorithm has a significant advantage in its ability to detect small target pests.To accurately obtain the data for the newly added pests each day,a two-stage pest matching algorithm was proposed.The algorithm performed well and achieved results that were highly consistent with manual counting,with a mean error of only 2.2%.This intelligent monitoring system realizes precision,good visualization,and intelligent vegetable pest monitoring,which is of great significance as it provides an effective pest prevention and control option for farmers. 展开更多
关键词 vegetable pests yellow sticky boards intelligent monitoring system deep learning pest detection
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Hierarchical FeO_(χ)H_(y)@Ni_(3)B hybrid for efficient alkaline oxygen evolution at high current density
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作者 Fuxi liu Qing liang +5 位作者 zhenyu li Meiqi liu Nailin Yue Zizhun Wang Xu Zou Wei Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第7期599-607,共9页
Electrocatalysts with high activity and long-term durability are vital toward large-scale hydrogen pro-duction from electrocatalytic water splitting.Here,the self-supported electrode(FeO_(χ)H_(y)@Ni_(3)B/NF)with hier... Electrocatalysts with high activity and long-term durability are vital toward large-scale hydrogen pro-duction from electrocatalytic water splitting.Here,the self-supported electrode(FeO_(χ)H_(y)@Ni_(3)B/NF)with hierarchical heterostructure was simply prepared by using Ni_(3)B chunks grown on nickel foam as sub-strate to in situ form vertical FeO_(χ)H_(y)nanosheets.Such hybrid shows efficient oxygen evolution reaction activity with overpotentials as low as 267 and 249 mV at 100 mA cm^(-2)in 1 M KOH solution and 30 wt%KOH solution,respectively.Meanwhile,it also exhibits excellent catalytic stability,sustaining catalysis at 500 mA cm^(-2)in 1 M KOH solution for 200 h,and even for 200 h at 1000 mA cm^(-2)in 30 wt%KOH solution.Further experimental results reveal that the FeO_(χ)H_(y)@Ni_(3)B/NF is endowed with superhydrophilic and superaerophobic surface properties,which not only provide more mass transport channels,as well as facilitated the diffusion of reaction intermediates and gas bubbles.Also,it holds faster reaction kinetics,more accessible active sites and accelerated electron transfer rates due to strong synergistic interactions attheheterogeneous interface. 展开更多
关键词 FeO_(χ)H_(y)@Ni_(3)B/NF hybrid Heterostructure Oxygen evolution reaction ELECTROCATALYTIC
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First-Principles Study of Blue Phosphorene and Graphene Intralayer Heterostructure as Anode Materials for Rechargeable Li-lon Batteries
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作者 Chunjie Sui Jiale Ma +1 位作者 Songtao Zhao zhenyu li 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2024年第5期653-661,I0073-I0077,I0100,共15页
There is an ideal desire to develop the high-performance anodes materials for Liion batteries(LIBs),which requires not onlyhigh stability and reversibility,but also rapidcharging/discharging rate.In this work,webuilta... There is an ideal desire to develop the high-performance anodes materials for Liion batteries(LIBs),which requires not onlyhigh stability and reversibility,but also rapidcharging/discharging rate.In this work,webuiltablue phosphorene-graphene(BlueP-G)intralayer heterostructure by connecting BlueP and graphene monolayers at zigzag edges with covalent bonds.Based on the density functional theory simulation,the electronic structure of the heterostructure,Li adsorption and Li diffusion on heterostructure were systematically investigated.Compared with the pristine BlueP,the existence of graphene layer increases the overall conductivity of BlueP-G intralayer heterostructure.The significantly enhanced adsorption energy indicates the Li deposition on anode surface is energetically favored.The fast diffusion of Li with energy barrier as low as 0.02-0.09 eV indicates the growth of Li dendrite could be suppressed and the stability and reversibility of the battery will be increased.With a combination of increased conductivity of electronic charge,excellent Li adsorption and Li mobility on surface,BlueP-G intralayer heterostructure with zigzag interface is quite promising in the application of anode material for Li-ion batteries. 展开更多
关键词 Li-ion battery Blue phosphorene Anode material Density functional theory
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Oxidation of 2,5‐bis(hydroxymethyl)furan to 2,5‐furandicarboxylic acid catalyzed by carbon nanotube‐supported Pd catalysts 被引量:2
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作者 zhenyu li liyuan Huai +5 位作者 Panpan Hao Xi Zhao Yongzhao Wang Bingsen Zhang Chunlin Chen Jian Zhang 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第3期793-801,共9页
The selective oxidation of 2,5‐bis(hydroxymethyl)furan(BHMF)in this work was proven as a promising route to produce 2,5‐furandicarboxylic acid(FDCA),an emerging bio‐based building‐block with wide application.Under... The selective oxidation of 2,5‐bis(hydroxymethyl)furan(BHMF)in this work was proven as a promising route to produce 2,5‐furandicarboxylic acid(FDCA),an emerging bio‐based building‐block with wide application.Under ambient pressure,the modified carbon nanotube‐supported Pd‐based catalysts demonstrate the maximum FDCA yield of 93.0%with a full conversion of BHMF after 60 min at 60°C,much superior to that of the traditional route using 5‐hydroxymethylfurfural(HMF)as substrates(only a yield of 35.7%).The participation of PdH_(x) active species with metallic Pd can be responsible for the encouraging performance.Meanwhile,a possible reaction pathway proceeding through 2,5‐diformylfuran(DFF)and 5‐formyl‐2‐furancarboxylic acid(FFCA)as process intermediates is suggested for BHMF route.The present work may provide new opportunities to synthesize other high value‐added oxygenates by using BHMF as an alternative feedstock. 展开更多
关键词 2 5‐Bis(hydroxymethyl)furan 2 5‐Furandicarboxylic acid Palladium hydride 5‐Hydroxymethylfurfural Catalytic oxidation
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Clinical analysis of concurrent chemoradiotherapy in 83 patients with locally advanced non-small cell lung cancer 被引量:3
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作者 Zhihua Sun Qjnfeng li +3 位作者 zhenyu li Yeshan Chen Yao Jiang Gang Wu 《The Chinese-German Journal of Clinical Oncology》 CAS 2012年第1期1-5,共5页
Objective:The purpose of this study was to evaluate the efficacy and safety of concurrent chemoradiotherapy (CCRT) in patients with locally advanced non-small cell lung cancer (LANSCLC). Methods:83 cases of patients w... Objective:The purpose of this study was to evaluate the efficacy and safety of concurrent chemoradiotherapy (CCRT) in patients with locally advanced non-small cell lung cancer (LANSCLC). Methods:83 cases of patients who have been diagnosed for locally advanced NSCLC by determined cytology or pathology were divided into two groups randomly, 42 patients in NP group and 41 patients in EP group. All patients accepted thoracic three-dimensional conformal radiotherapy (3D-CRT) and concurrent either NP chemotherapy in NP group or EP chemotherapy in EP group. 3D-CRT were started on day 1 in the first cycle of chemotherapy. Chemotherapy were carried out for 4 cycles, every cycle was 21 days. Thoracic radiotherapy adopted conventional fractionated irradiation with 15 MeV-X ray, a total dose of 60 Gy. Results: In 83 patients were evaluable, there were 5 cases complete regression to be observed, 29 cases had partial regression (PR), 7 cases with stable disease (SD) and 1 case with progression disease (PD) in NP group. CR 3 cases, PR 27 cases, SD 9 cases and PD 2 cases in EP group. The overall response rate (RR) both NP group and EP group were 80.9%, 73.2%, respectively (P = 0.785).1-, 2-, 3-year survival rate were 90.5%, 69.0%, 28.6% and 82.9%, 51.2%, 21.9%, respectively (P = 0.393). The incidence of leukopenia and thrombocytopenia in NP group was higher than that in the EP group (P < 0.05). Conclusion:CCRT in patients with locally advanced non-small cell lung cancer, 3D-CRT with concurrent NP or EP chemotherapy. 1-, 2-, 3-year overall survival (OS) and average survival time (AST) were not statistically differences, a higher incidence of toxicities were observed in NP group but can be tolerable. 展开更多
关键词 locally advanced non-small cell lung cancer (LANSCLC) three-dimensional conformal radiotherapy concurrentchemotherapy SURVIVAL TOXICITY
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An Image Steganography Algorithm Based on Quantization Index Modulation Resisting Scaling Attacks and Statistical Detection 被引量:1
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作者 Yue Zhang Dengpan Ye +2 位作者 Junjun Gan zhenyu li Qingfeng Cheng 《Computers, Materials & Continua》 SCIE EI 2018年第7期151-167,共17页
In view of the fact that the current adaptive steganography algorithms are difficult to resist scaling attacks and that a method resisting scaling attack is only for the nearest neighbor interpolation method,this pape... In view of the fact that the current adaptive steganography algorithms are difficult to resist scaling attacks and that a method resisting scaling attack is only for the nearest neighbor interpolation method,this paper proposes an image steganography algorithm based on quantization index modulation resisting both scaling attacks and statistical detection.For the spatial image,this paper uses the watermarking algorithm based on quantization index modulation to extract the embedded domain.Then construct the embedding distortion function of the new embedded domain based on S-UNIWARD steganography,and use the minimum distortion coding to realize the embedding of the secret messages.Finally,according to the embedding modification amplitude of secret messages in the new embedded domain,the quantization index modulation algorithm is applied to realize the final embedding of secret messages in the original embedded domain.The experimental results show that the algorithm proposed is robust to the three common interpolation attacks including the nearest neighbor interpolation,the bilinear interpolation and the bicubic interpolation.And the average correct extraction rate of embedded messages increases from 50%to over 93% after 0.5 times-fold scaling attack using the bicubic interpolation method,compared with the classical steganography algorithm S-UNIWARD.Also the algorithm proposed has higher detection resistance than the original watermarking algorithm based on quantization index modulation. 展开更多
关键词 Image steganography anti-scaling attack anti-statistical detection quantization index modulation
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The application of internal suspension technique in retroperitoneal robot-assisted laparoscopic partial nephrectomy with a new robotic system KangDuo Surgical Robot-01:Initial experience
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作者 Silu Chen Shubo Fan +8 位作者 Hua Guan Kunlin Yang Zhihua li Shengwei Xiong Xiang Wang zhenyu li Cheng Shen liqun Zhou Xuesong li 《Asian Journal of Urology》 CSCD 2023年第4期482-487,共6页
Objective To assess the feasibility of internal suspension technique in retroperitoneal robot-assisted laparoscopic partial nephrectomy(rRAPN)with a new robotic platform called KangDuo Surgical Robot-01(KD-SR-01)syste... Objective To assess the feasibility of internal suspension technique in retroperitoneal robot-assisted laparoscopic partial nephrectomy(rRAPN)with a new robotic platform called KangDuo Surgical Robot-01(KD-SR-01)system(Suzhou KangDuo Robot Co.,Ltd.,Suzhou,China)and discuss its surgical technique.Methods A 44-year-old male patient was admitted with a 2.5 cm tumor on dorsolateral upper pole of the left kidney.The R.E.N.A.L.nephrometry score of this patient was 4x.This patient underwent rRAPN with KD-SR-01.The perinephric fat between the tumor and Gerota's fascia was preserved,which was used for internal suspension traction during tumor resection.Postoperative follow-up data were collected.Results The surgery was successfully carried out with a duration of 127 min,in which the docking time was 6 min 25 s and console time was 60 min.The warm ischemia time was 19 min 53 s,and the estimated blood loss was 0 mL.The pathological histology showed a pathological tumor stage 1a clear cell renal cell carcinoma,with a negative surgical margin.The World Health Organization/International Society of Urological Pathology(WHO/ISUP)grade of this patient was Grade 2.No recurrence was observed during the 6-month follow-up.Conclusion Internal suspension in rRAPN is feasible and effective with use of the new robotic system KD-SR-01. 展开更多
关键词 KangDuo Surgical Robot-01 Internal suspension Partial nephrectomy Retroperitoneal approach
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Crowd Counting Based on WiFi Channel State Information and Transfer Learning
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作者 Zhongqiang Wu Pengyu Ji +4 位作者 Manxi Ma Wencheng Zhuang zhenyu li Jihao Cui Zhengjie Wang 《Journal of Computer and Communications》 2022年第6期22-36,共15页
With the popularity and development of indoor WiFi equipment, they have more sensing capability and can be used as a human monitoring device. We can collect the channel state information (CSI) from WiFi device and acq... With the popularity and development of indoor WiFi equipment, they have more sensing capability and can be used as a human monitoring device. We can collect the channel state information (CSI) from WiFi device and acquire the human state based on the measurements. These studies have attracted wide attention and become a hot research topic. This paper concentrated on the crowd counting based on CSI and transfer learning. We utilized the CSI signal fluctuations caused by human motion in WiFi coverage to identify the person count because different person counts would lead to unique signal propagation characteristics. First, this paper presented recent studies of crowd counting based on CSI. Then, we introduced the basic concept of CSI, and described the fundamental principle of CSI-based crowd counting. We also presented the system framework, experiment scenario, and neural network structure transferred from the ResNet. Next, we presented the experiment results and compared the accuracy using different neural network models. The system achieved recognition accuracy of this 100 percent for seven participants using the transfer learning technique. Finally, we concluded the paper by discussing the current problems and future work. 展开更多
关键词 Crowd Counting Channel Status Information Transfer Learning ResNet
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基于可逆硼氧六元环交联的自修复聚氨酯
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作者 易明 王犁 +8 位作者 来婧娟 安鹏 周利华 李振宇 武元鹏 郑朝晖 丁小斌 杨小林 肖立 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2023年第5期125-133,共9页
自修复聚氨酯一直是近年来的研究热点。文中以聚四氢呋喃二醇(PTMEG)、异佛尔酮二异氰酸酯(IPDI)和4-羟基苯硼酸(HPBA)为原材料,制备了基于硼氧六元环的高强度自修复聚氨酯(PU)。利用傅里叶变换红外光谱仪对其进行结构表征;利用热重分... 自修复聚氨酯一直是近年来的研究热点。文中以聚四氢呋喃二醇(PTMEG)、异佛尔酮二异氰酸酯(IPDI)和4-羟基苯硼酸(HPBA)为原材料,制备了基于硼氧六元环的高强度自修复聚氨酯(PU)。利用傅里叶变换红外光谱仪对其进行结构表征;利用热重分析和差示扫描量热法考察其热性能;研究了PU的力学性能、自修复性能和形状记忆性能。结果表明,硼氧六元环结构的引入使PU具有高强度和优异的自修复性能。当HPBA含量从0 mmol增加到0.75 mmol时,PU的拉伸强度从(23.8±1.8)MPa提高到(51.3±4.2)MPa;在80℃修复36 h后,PU/P-0.7的修复效率达到80.9%±4.2%。此外,PU还具有热响应的形状记忆性能,75℃时,其形状回复率达到96.1%±1.7%。利用凝胶渗透色谱法测试了PU的相对分子质量,其数均分子量为3.28×10^(4)。 展开更多
关键词 聚氨酯 硼氧六元环 高强度 自修复 形状记忆
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Flexural Capacity Formula of Diaphragm-Through Joints of Concrete-Filled Square Steel Tubular Columns 被引量:1
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作者 Bin Rong Rui liu +3 位作者 zhenyu li Changxi Feng Guangchao You Fafitis Apostolos 《Transactions of Tianjin University》 EI CAS 2017年第3期258-266,共9页
Finite element analysis and parametric studies were performed to investigate the flexural capacity of the panel zone of diaphragm-through joints between concrete-filled square steel tubular columns and H-shaped steel ... Finite element analysis and parametric studies were performed to investigate the flexural capacity of the panel zone of diaphragm-through joints between concrete-filled square steel tubular columns and H-shaped steel beams. Through the comparisons of failure modes, load–displacement curves, and bearing capacity, it was found that the flexural capacity of the panel zone of diaphragm-through joints was determined by the tensile action and influence of the web of H-shaped steel beams, and the axial load should be taken into account. The steel tube and the diaphragm were the major parts of the joint that resisted the bending moment. The contribution of in-filled concrete had little influence on the flexural capacity of the panel zone of the joint and could be neglected. According to the results of these numerical studies, a formula that considered the influence of the web of H-shaped steel beams and the axial load was developed based on the yield lines in the diaphragm and the steel tube. The results of the proposed formula were in good agreement with the numerical data of this investigation. © 2017, Tianjin University and Springer-Verlag Berlin Heidelberg. 展开更多
关键词 Axial loads CONCRETES DIAPHRAGMS Steel beams and girders Tubular steel structures Web crawler
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心血来潮:肾上腺素的诞生与发展 被引量:1
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作者 黎卓熹 吴海涛 +2 位作者 蔡子濠 李镇宇 周士忠 《大学化学》 CAS 2023年第2期147-153,共7页
肾上腺素作为人体内重要的激素,能兴奋心血管系统。本文利用拟人的手法,结合浅显易懂的医学知识、案例及历史故事,简述肾上腺素及其衍生物的发现历史、发展过程及临床用途。
关键词 肾上腺素 肾上腺素类药物 化学史 药学史
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Experimental and Numerical Studies of Failure Modes and Load-Carrying Capacity of Through-Diaphragm Connections
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作者 Bin Rong Shuai liu +1 位作者 zhenyu li Rui liu 《Transactions of Tianjin University》 EI CAS 2018年第4期387-400,共14页
Shear failure in panel zones and plastic hinges in steel beams are the two major failure modes of connections between concrete-filled steel tubular(CFST) columns and steel beams. To investigate the behavior of this ty... Shear failure in panel zones and plastic hinges in steel beams are the two major failure modes of connections between concrete-filled steel tubular(CFST) columns and steel beams. To investigate the behavior of this type of connection in both modes,two through-diaphragm connections were tested under cyclic and monotonic loadings and the load-carrying capacity,ductility,and strength of degradation of connections were discussed. Using ABAQUS software,we developed nonlinear finite-element models(FEMs) to simulate the load-carrying capacity and failure modes of the connections under monotonic loading. The finite-element(FE) analysis and test results showed reasonable agreement for the through-diaphragm connections,which confirms the accuracy of FEMs in predicting the load-carrying capacity and failure modes of connections. Based on the validated FEM,a parametric study was then conducted to investigate the infl uence of the thicknesses of the tube and diaphragm on the load-carrying capacity and failure modes of these connections. The results indicate that the strength,stiff ness,and load-carrying capacity are infl uenced less by the thickness of the diaphragm,and more by the thickness of the steel tube. According to the FE analysis results,it can be found that the critical condition between the two failure modes is determined by the shear resistance and bending resistance. 展开更多
关键词 Through-diaphragm CONNECTIONS Failure mode FINITE-ELEMENT ANALYSIS Parametric ANALYSIS Monotonic LOADING Cyclic LOADING
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Computational Characterization of Nanosystems
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作者 Xiongzhi Zeng Wei Hu +3 位作者 Xiao Zheng Jin Zhao zhenyu li Jinlong Yang 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2022年第1期1-15,I0062,共16页
Nanosystems play an important role in many applications.Due to their complexity,it is challenging to accurately characterize their structure and properties.An important means to reach such a goal is computational simu... Nanosystems play an important role in many applications.Due to their complexity,it is challenging to accurately characterize their structure and properties.An important means to reach such a goal is computational simulation,which is grounded on ab initio electronic structure calculations.Low scaling and accurate electronic-structure algorithms have been developed in recent years.Especially,the efficiency of hybrid density functional calculations for periodic systems has been significantly improved.With electronic structure information,simulation methods can be developed to directly obtain experimentally comparable data.For example,scanning tunneling microscopy images can be effectively simulated with advanced algorithms.When the system we are interested in is strongly coupled to environment,such as the Kondo effect,solving the hierarchical equations of motion turns out to be an effective way of computational characterization.Furthermore,the first principles simulation on the excited state dynamics rapidly emerges in recent years,and nonadiabatic molecular dynamics method plays an important role.For nanosystem involved chemical processes,such as graphene growth,multiscale simulation methods should be developed to characterize their atomic details.In this review,we review some recent progresses in methodology development for computational characterization of nanosystems.Advanced algorithms and software are essential for us to better understand of the nanoworld. 展开更多
关键词 Density functional theory Linear-scaling algorithms Open system Nonadiabatic molecular dynamics Multiscale methods
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Self-embedding Image Watermarking based on Combined Decision Using Pre-offset and Post-offset Blocks
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作者 Daofu Gong Yan Chen +2 位作者 Haoyu Lu zhenyu li Yibing Han 《Computers, Materials & Continua》 SCIE EI 2018年第11期243-260,共18页
To detect and recover random tampering areas,a combined-decision-based self-embedding watermarking scheme is proposed herein.In this scheme,the image is first partitioned into 2×2 size blocks.Next,the high 5 bits... To detect and recover random tampering areas,a combined-decision-based self-embedding watermarking scheme is proposed herein.In this scheme,the image is first partitioned into 2×2 size blocks.Next,the high 5 bits of a block’s average value is embedded into its offset block.The tampering type of block is detected by comparing the watermarks of its pre-offset and post-offset blocks.The theoretical analysis and experiments demonstrate that the proposed scheme not only has a lower ratio of false detection but also better performance with regard to avoiding random tampering. 展开更多
关键词 Fragile watermarking SELF-EMBEDDING offset block tamper recovery random tampering
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量子平方:一个聚焦于量子化学模拟的量子计算平台
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作者 范逸 刘杰 +4 位作者 曾雄志 徐直前 商红慧 李震宇 杨金龙 《中国科学技术大学学报》 CAS CSCD 北大核心 2022年第12期10-21,共12页
量子计算机为量子化学的发展提供了新的机遇。本文开发了一个多功能、可扩展、高性能的软件包“量子平方”,用于发展量子化学领域的量子算法以及启发于量子计算的经典算法。使用“量子平方”软件包,可以便捷地将波函数和哈密顿量映射到... 量子计算机为量子化学的发展提供了新的机遇。本文开发了一个多功能、可扩展、高性能的软件包“量子平方”,用于发展量子化学领域的量子算法以及启发于量子计算的经典算法。使用“量子平方”软件包,可以便捷地将波函数和哈密顿量映射到量子比特空间中,然后根据软件内部集成的或由用户自主编写的量子算法生成对应的量子线路。之后,该线路可以被接入可用的量子计算机硬件,或者使用经典计算机上的量子线路模拟器运行。本文使用“量子平方”进行了高达72量子比特的模拟测试,测试结果展现了其优秀的性能。研究展示了“量子平方”软件包在分子体系和周期性体系模拟中的应用,并给出了性能分析。 展开更多
关键词 量子算法 量子线路 电子结构 矩阵乘积态
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Cryptanalysis and Improvement of a Chaotic Map-Control-Based and the Plain Image-Related Cryptosystem
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作者 Bin Lu Fenlin liu +1 位作者 Xin Ge zhenyu li 《Computers, Materials & Continua》 SCIE EI 2019年第8期687-699,共13页
Due to the characteristics of chaotic systems,different cryptosystems based on chaos have been proposed to satisfy the security of multimedia data.A plain image-related chaotic algorithm is proposed by Luo et al.with ... Due to the characteristics of chaotic systems,different cryptosystems based on chaos have been proposed to satisfy the security of multimedia data.A plain image-related chaotic algorithm is proposed by Luo et al.with high speed and efficiency.Security weaknesses of the cryptosystem are studied in this paper.It is found that the important secret key information is leaked because an important parameter can be obtained after an inverse operation in the last step of the cryptosystems without secret key.Meanwhile,the value zero is processed improperly in quantification algorithm.Based on the weaknesses,chosen plaintext attack on the cryptosystem is proposed,by which,an important parameter,equivalent to secret key,can be calculated with a specific chosen plain image.With the obtained parameter,the plain image of any ciphered image,encrypted by the cryptosystem,can be recovered.Then,an improvement is proposed to solve the problems after modifying the quantification algorithm.It is from the experiments that chosen plaintext attack is valid and improved algorithm possesses better performance. 展开更多
关键词 Multimedia cryptosystem CRYPTANALYSIS CHAOS chosen plaintext attack
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Self-Supervised Monocular Depth Estimation via Discrete Strategy and Uncertainty
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作者 zhenyu li Junjun Jiang Xianming liu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2022年第7期1307-1310,共4页
Dear Editor,This letter is concerned with self-supervised monocular depth estimation.To estimate uncertainty simultaneously,we propose a simple yet effective strategy to learn the uncertainty for self-supervised monoc... Dear Editor,This letter is concerned with self-supervised monocular depth estimation.To estimate uncertainty simultaneously,we propose a simple yet effective strategy to learn the uncertainty for self-supervised monocular depth estimation with the discrete strategy that explicitly associates the prediction and the uncertainty to train the networks.Furthermore,we propose the uncertainty-guided feature fusion module to fully utilize the uncertainty information.Codes will be available at https://github.com/zhyever/Monocular-Depth-Estimation-Toolbox.Self-supervised monocular depth estimation methods turn into promising alternative trade-offs in both the training cost and the inference performance.However,compound losses that couple the depth and the pose lead to a dilemma of uncertainty calculation that is crucial for critical safety systems.To solve this issue,we propose a simple yet effective strategy to learn the uncertainty for self-supervised monocular depth estimation using the discrete bins that explicitly associate the prediction and the uncertainty to train the networks.This strategy is more pluggable without any additional changes to self-supervised training losses and improves model performance.Secondly,to further exert the uncertainty information,we propose the uncertainty-guided feature fusion module to refine the depth estimation. 展开更多
关键词 ESTIMATION utilize UNCERTAINTY
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A Left-Handed, Stem-Twining Plant from the Miocene Shanwang Formation of Eastern China
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作者 Qi Wang Si Shen zhenyu li 《American Journal of Plant Sciences》 2013年第5期18-22,共5页
Twining stems of plants are very common in extant tropical and subtropical forests, and the climbing growth habit of plants may be an evolutionary innovation and ecological adaptation to either closed, shady or open, ... Twining stems of plants are very common in extant tropical and subtropical forests, and the climbing growth habit of plants may be an evolutionary innovation and ecological adaptation to either closed, shady or open, edge environments. However, the origin of handedness in climbing plants remains unclear. Here we report a Miocene (ca. 16 million years ago) macrofossil from the Shanwang Formation of Shandong Province, Eastern China, unequivocally exhibiting the first direct fossil evidence for a left-handed, stem-twining growth habit in plants. This fossil plant bears a thicker, slightly curved supporting stem (2 - 3.5 mm wide), which is loosely, spirally twined by a thinner stem (1.5 - 2 mm wide), possibly representing part of distal branches from a liana or vine. 展开更多
关键词 Climbing Growth HABIT HANDEDNESS LIANA MIOCENE SHANWANG Formation Stem-Twining Plants Vine
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Construction of recombinant type 5 adenovirus expressing human DBC2 gene in bladder cancer cells
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作者 Xu Chen Jianyin Chen +3 位作者 Yin Shi zhenyu li Bin li Chuanguo Xiao 《The Chinese-German Journal of Clinical Oncology》 CAS 2010年第5期266-269,共4页
Objective:The aim of the study was to construct recombinant type 5 adenovirus expressing the human DBC2(deleted in breast cancer 2) gene for in vitro and in vivo assay in human bladder cancer research.Methods:The huma... Objective:The aim of the study was to construct recombinant type 5 adenovirus expressing the human DBC2(deleted in breast cancer 2) gene for in vitro and in vivo assay in human bladder cancer research.Methods:The human DBC2 gene was first subcloned into a shuttle plasmid pAdTrack-CMV.After recombining with pAdEasy-1 vector in BJ5183 cells,the new recombinant vector pAdEasy-DBC2-CMV was transfected into HEK-293 cells to produce adenovirus.The human bladder cancer cell line T24 was infected with DBC2-containing adenovirus particles.Both RNA and protein were collected from cells harvested at 72 h after infection.Real time quantitative PCR(qPCR) and Western blot were used to examine mRNA and protein levels.Fluorescence microscopy was utilized to observe the expression of reporter green fluorescence protein.Results:Electrophoresis showed there was a 2.2 kb size band produced from high fidelity PCR.Pac I digest of the final produced recombinant vector yielded band sizes of approximately 30 kb and 4.5 kb.After virus infection with the pAdEasy-DBC2-CMV vector,the T24 cell line was observed to highly express green fluorescence protein under a fluorescence microscope.qPCR and Western blot assay identified that the DBC2 gene was overexpressed at both the mRNA and protein levels in virus transfected cells.Conclusion:By using the pAdEasy adenovirus system,we successfully constructed an adenovirus that could highly overexpress the tumor suppressor DBC2 gene in a bladder cancer cell line.This viral construct would be widely used for our further research in gene functional assays and gene therapy in bladder cancer. 展开更多
关键词 DBC2(deleted in breast cancer 2) recombinant adenovirus bladder cancer gene therapy
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Summary on the Harmonious Relationship between Urban Lake Landscapes and Lakeshore Architectural Image
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作者 zhenyu li 《International Journal of Technology Management》 2013年第6期14-16,共3页
A variety of high-rise building landscapes are trying to invade urban lakes resulting in the shrinkage, fragmentation, pollution of lakes and cut-down of vegetation along lakes. With the development of real estate alo... A variety of high-rise building landscapes are trying to invade urban lakes resulting in the shrinkage, fragmentation, pollution of lakes and cut-down of vegetation along lakes. With the development of real estate along lakes, the local marginal lines and natural landscapes nearby are disappearing. How to plan urban landscapes'? How to achieve the harmonious relationship between lakeshore landscapes and lakeshore architectural image? How to render lake sights an organic and sustainable whole? How to balance the interest between economy and value for each interest group? How to form urban lake sights and architectural images? How to utilize and arrange the space? How to form a harmonious relationship between the lake scenes and buildings in the city? Through on-the-spot investigation and profound analysis of several lakes in Wuhan, applying enumeration, induction and analysis, the dissertation reveals that people need to share natural resources and get the support from laws and policies with the aim of building a beautiful home. In tmaa, people's anticipation is needed to achieve a harmonious relationship between landscapes and architectures. 展开更多
关键词 Stability of ecological landscape Continuity of landscape system NODE AXIS Balance of value
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