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The Application of Nicotiana benthamiana as a Transient Expression Host to Clone the Coding Sequences of Plant Genes
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作者 Jianzhong Huang Peng Jia +3 位作者 Xiaoju Zhong Xiuying Guan Hongbin Zhang Honglei Ruan 《American Journal of Molecular Biology》 CAS 2024年第2期54-65,共12页
Coding sequences (CDS) are commonly used for transient gene expression, in yeast two-hybrid screening, to verify protein interactions and in prokaryotic gene expression studies. CDS are most commonly obtained using co... Coding sequences (CDS) are commonly used for transient gene expression, in yeast two-hybrid screening, to verify protein interactions and in prokaryotic gene expression studies. CDS are most commonly obtained using complementary DNA (cDNA) derived from messenger RNA (mRNA) extracted from plant tissues and generated by reverse transcription. However, some CDS are difficult to acquire through this process as they are expressed at extremely low levels or have specific spatial and/or temporal expression patterns in vivo. These challenges require the development of alternative CDS cloning technologies. In this study, we found that the genomic intron-containing gene coding sequences (gDNA) from Arabidopsis thaliana, Oryza sativa, Brassica napus, and Glycine max can be correctly transcribed and spliced into mRNA in Nicotiana benthamiana. In contrast, gDNAs from Triticum aestivum and Sorghum bicolor did not function correctly. In transient expression experiments, the target DNA sequence is driven by a constitutive promoter. Theoretically, a sufficient amount of mRNA can be extracted from the N. benthamiana leaves, making it conducive to the cloning of CDS target genes. Our data demonstrate that N. benthamiana can be used as an effective host for the cloning CDS of plant genes. 展开更多
关键词 Coding sequence Genomic sequence Nicotiana benthamiana Plant Genes
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Pig pangenome graph reveals functional features of non‑reference sequences
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作者 Jian Miao Xingyu Wei +6 位作者 Caiyun Cao Jiabao Sun Yuejin Xu Zhe Zhang Qishan Wang Yuchun Pan Zhen Wang 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第3期956-970,共15页
Background The reliance on a solitary linear reference genome has imposed a significant constraint on our compre-hensive understanding of genetic variation in animals.This constraint is particularly pronounced for non... Background The reliance on a solitary linear reference genome has imposed a significant constraint on our compre-hensive understanding of genetic variation in animals.This constraint is particularly pronounced for non-reference sequences(NRSs),which have not been extensively studied.Results In this study,we constructed a pig pangenome graph using 21 pig assemblies and identified 23,831 NRSs with a total length of 105 Mb.Our findings revealed that NRSs were more prevalent in breeds exhibiting greater genetic divergence from the reference genome.Furthermore,we observed that NRSs were rarely found within coding sequences,while NRS insertions were enriched in immune-related Gene Ontology terms.Notably,our investigation also unveiled a close association between novel genes and the immune capacity of pigs.We observed substantial differences in terms of frequencies of NRSs between Eastern and Western pigs,and the heat-resistant pigs exhibited a substantial number of NRS insertions in an 11.6 Mb interval on chromosome X.Additionally,we discovered a 665 bp insertion in the fourth intron of the TNFRSF19 gene that may be associated with the ability of heat tolerance in South-ern Chinese pigs.Conclusions Our findings demonstrate the potential of a graph genome approach to reveal important functional features of NRSs in pig populations. 展开更多
关键词 Heat tolerance Immune ability Non-reference sequences Pig pangenome
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Mitochondrial targeting sequence of magnetoreceptor MagR:More than just targeting
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作者 Yanqi Zhang Peng Zhang +10 位作者 Junjun Wang Jing Zhang Tianyang Tong Xiujuan Zhou Yajie Zhou Mengke Wei Chuanlin Feng Jinqian Li Xin Zhang Can Xie Tiantian Cai 《Zoological Research》 SCIE CSCD 2024年第3期468-477,共10页
Iron-sulfur clusters(ISC)are essential cofactors for proteins involved in various biological processes,such as electron transport,biosynthetic reactions,DNA repair,and gene expression regulation.ISC assembly protein I... Iron-sulfur clusters(ISC)are essential cofactors for proteins involved in various biological processes,such as electron transport,biosynthetic reactions,DNA repair,and gene expression regulation.ISC assembly protein IscA1(or MagR)is found within the mitochondria of most eukaryotes.Magnetoreceptor(MagR)is a highly conserved A-type iron and iron-sulfur cluster-binding protein,characterized by two distinct types of iron-sulfur clusters,[2Fe-2S]and[3Fe-4S],each conferring unique magnetic properties.MagR forms a rod-like polymer structure in complex with photoreceptive cryptochrome(Cry)and serves as a putative magnetoreceptor for retrieving geomagnetic information in animal navigation.Although the N-terminal sequences of MagR vary among species,their specific function remains unknown.In the present study,we found that the N-terminal sequences of pigeon MagR,previously thought to serve as a mitochondrial targeting signal(MTS),were not cleaved following mitochondrial entry but instead modulated the efficiency with which iron-sulfur clusters and irons are bound.Moreover,the N-terminal region of MagR was required for the formation of a stable MagR/Cry complex.Thus,the N-terminal sequences in pigeon MagR fulfil more important functional roles than just mitochondrial targeting.These results further extend our understanding of the function of MagR and provide new insights into the origin of magnetoreception from an evolutionary perspective. 展开更多
关键词 Magnetoreceptor(MagR) N-terminal sequence Mitochondrial targeting signal Iron-sulfur cluster
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Landscape of Sequence Variations in Homologous Copies of FAD2 and FAD3 in Rapeseed(Brassica napus L.)Germplasm with High/Low Linolenic Acid Trait
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作者 Haoxue Wu Xiaohan Zhang +5 位作者 Xiaoyu Chen Kang Li Aixia Xu Zhen Huang Jungang Dong Chengyu Yu 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第3期627-640,共14页
Genetic manipulation(either restraint or enhancement)of the biosynthesis pathway ofα-linolenic acid(ALA)in seed oil is an important goal in Brassica napus breeding.B.napus is a tetraploid plant whose genome often har... Genetic manipulation(either restraint or enhancement)of the biosynthesis pathway ofα-linolenic acid(ALA)in seed oil is an important goal in Brassica napus breeding.B.napus is a tetraploid plant whose genome often har-bors four and six homologous copies,respectively,of the two fatty acid desaturases FAD2 and FAD3,which con-trol the last two steps of ALA biosynthesis during seed oil accumulation.In this study,we compared their promoters,coding sequences,and expression levels in three high-ALA inbred lines 2006L,R8Q10,and YH25005,a low-ALA line A28,a low-ALA/high-oleic-acid accession SW,and the wildtype ZS11.The expression levels of most FAD2 and FAD3 homologs in the three high-ALA accessions were higher than those in ZS11 and much higher than those in A28 and SW.The three high-ALA accessions shared similar sequences with the pro-moters and CDSs of BnFAD3.C4 and BnFAD3.A3.In A28 and SW,substitution of three amino acid residues in BnFAD2.A5 and BnFAD2.C5,an absence of BnFAD2.C1 locus,and a 549 bp long deletion on the BnFAD3.A3 promoter were detected.The profile of BnFAD2 mutation in the two low-ALA accessions A28 and SW is different from that reported in previous studies.The mutations in BnFAD3 in the high-ALA accessions are reported for thefirst time.In identifying the sites of these mutations,we provide detailed information to aid the design of mole-cular markers for accelerated breeding schemes. 展开更多
关键词 Brassica napus linolenic acid FAD2 FAD3 promoter coding sequences mutation
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Secure Transmission of Compressed Medical Image Sequences on Communication Networks Using Motion Vector Watermarking
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作者 Rafi Ullah Mohd Hilmi bin Hasan +1 位作者 Sultan Daud Khan Mussadiq Abdul Rahim 《Computers, Materials & Continua》 SCIE EI 2024年第3期3283-3301,共19页
Medical imaging plays a key role within modern hospital management systems for diagnostic purposes.Compression methodologies are extensively employed to mitigate storage demands and enhance transmission speed,all whil... Medical imaging plays a key role within modern hospital management systems for diagnostic purposes.Compression methodologies are extensively employed to mitigate storage demands and enhance transmission speed,all while upholding image quality.Moreover,an increasing number of hospitals are embracing cloud computing for patient data storage,necessitating meticulous scrutiny of server security and privacy protocols.Nevertheless,considering the widespread availability of multimedia tools,the preservation of digital data integrity surpasses the significance of compression alone.In response to this concern,we propose a secure storage and transmission solution for compressed medical image sequences,such as ultrasound images,utilizing a motion vector watermarking scheme.The watermark is generated employing an error-correcting code known as Bose-Chaudhuri-Hocquenghem(BCH)and is subsequently embedded into the compressed sequence via block-based motion vectors.In the process of watermark embedding,motion vectors are selected based on their magnitude and phase angle.When embedding watermarks,no specific spatial area,such as a region of interest(ROI),is used in the images.The embedding of watermark bits is dependent on motion vectors.Although reversible watermarking allows the restoration of the original image sequences,we use the irreversible watermarking method.The reason for this is that the use of reversible watermarks may impede the claims of ownership and legal rights.The restoration of original data or images may call into question ownership or other legal claims.The peak signal-to-noise ratio(PSNR)and structural similarity index(SSIM)serve as metrics for evaluating the watermarked image quality.Across all images,the PSNR value exceeds 46 dB,and the SSIM value exceeds 0.92.Experimental results substantiate the efficacy of the proposed technique in preserving data integrity. 展开更多
关键词 Block matching algorithm(BMA) compression full-search algorithm motion vectors ultrasound image sequence WATERMARKING
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Optimal mining sequence for coal faces under a bedding slope:insight from landslide prevention
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作者 LI Qingmiao ZHAO Jianjun +3 位作者 LI Zhichao DENG Jie ZUO Jing LAI Qiyi 《Journal of Mountain Science》 SCIE CSCD 2024年第5期1775-1798,共24页
Repetitive mining beneath bedding slopes is identified as a critical factor in geomorphic disturbances, especially landslides and surface subsidence. Prior research has largely concentrated on surface deformation in p... Repetitive mining beneath bedding slopes is identified as a critical factor in geomorphic disturbances, especially landslides and surface subsidence. Prior research has largely concentrated on surface deformation in plains due to multi-seam coal mining and the instability of natural bedding slopes, yet the cumulative impact of different mining sequences on bedding slopes has been less explored. This study combines drone surveys and geological data to construct a comprehensive three-dimensional model of bedding slopes. Utilizing FLAC3D and PFC2D models, derived from laboratory experiments, it simulates stress, deformation, and failure dynamics of slopes under various mining sequences. Incorporating fractal dimension analysis, the research evaluates the stability of slopes in relation to different mining sequences. The findings reveal that mining in an upslope direction minimizes disruption to overlying strata. Initiating extraction from lower segments increases tensile-shear stress in coal pillar overburdens, resulting in greater creep deformation towards the downslope than when starting from upper segments, potentially leading to localized landslides and widespread creep deformation in mined-out areas. The downslope upward mining sequence exhibits the least fractal dimensions, indicating minimal disturbance to both strata and surface. While all five mining scenarios maintain good slope stability under normal conditions, recalibrated stability assessments based on fractal dimensions suggest that downslope upward mining offers the highest stability under rainfall, contrasting with the lower stability and potential instability risks of upslope downward mining. These insights are pivotal for mining operations and geological hazard mitigation in multi-seam coal exploitation on bedding slopes. 展开更多
关键词 Bedding rock landslides Mining-induced deformation Bedding slope stability Underground mining sequences Fractal-based strength reduction method
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Method and Description of Sedimentary System Characterization Based on Sequence Stratigraphy
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作者 Jianmin Zhang Hui Cai +1 位作者 Honglin Yue Pengfei Mu 《Journal of Geoscience and Environment Protection》 2024年第5期60-68,共9页
A Oilfield is the most representative mid to deep oil field in the Bohai Sea, with the main oil bearing intervals being the upper and middle Shahejie-3 sections of the Paleogene Shahejie Formation. By combining well s... A Oilfield is the most representative mid to deep oil field in the Bohai Sea, with the main oil bearing intervals being the upper and middle Shahejie-3 sections of the Paleogene Shahejie Formation. By combining well seismic analysis, the middle section of Shahejie-3 is divided into high-level system tract and forced lake retreat system tract, corresponding to the II oil formation and I oil formation, respectively. Using sequence stratigraphy methods, based on seismic profiles and drilling lithological cycles, the high stand system tract is divided into 5 stages of delta progradation. The first and second stages are high angle S-type progradation with large sedimentary thickness, the third stage is oblique progradation, and the fourth and fifth stages are S-oblique composite progradation;By combining seismic data, we characterized the large-scale (8 small-scale) progradation bodies of 5 periods, clarified the distribution characteristics of reservoir planes, and laid the foundation for the later exploration of oilfield potential. 展开更多
关键词 Middle Section of Shasan sequence Stratigraphy Sedimentary System CHARACTERIZATION
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Coseismic Coulomb stress changes induced by a 2020-2021 M_(W)>7.0 Alaska earthquake sequence in and around the Shumagin gap and its influence on the Alaska-Aleutian subduction interface
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作者 Lei Yang Jianjun Wang Caijun Xu 《Geodesy and Geodynamics》 EI CSCD 2024年第1期1-12,共12页
Three M_(W)>7.0 earthquakes in 2020-2021 occurred in the Shumagin seismic gap and its adjacent area of the Alaska-Aleutian subduction zone,including the Mw7.8 Simeonof thrust earthquake on July 22,2020,the M_(W)7.6... Three M_(W)>7.0 earthquakes in 2020-2021 occurred in the Shumagin seismic gap and its adjacent area of the Alaska-Aleutian subduction zone,including the Mw7.8 Simeonof thrust earthquake on July 22,2020,the M_(W)7.6 Sand Point strike-slip earthquake on October 19,2020,and the M_(W)8.2 Chignik thrust earthquake on July 29,2021.The spatial and temporal proximity of these three earthquakes prompts us to probe stress-triggering effects among them.Here we examine the coseismic Coulomb stress change imparted by the three earthquakes and their influence on the subduction interface.Our results show that:(1)The Simeonof earthquake has strong loading effects on the subsequent Sand Point and Chignik earthquakes,with the Coulomb stress changes of 3.95 bars and 2.89 bars,respectively.The Coulomb stress change caused by the Sand Point earthquake at the hypocenter of the Chignik earthquake is merely around 0.01 bars,suggesting the negligible triggering effect on the latter earthquake;(2)The triggering effects of the Simeonof,Sand Point,and Chignik earthquakes on aftershocks within three months are not well pronounced because of the triggering rates of 38%,14%,and 43%respectively.Other factors may have played an important role in promoting the occurrence of these aftershocks,such as the roughness of the subduction interface,the complicated velocity structure of the lithosphere,and the heterogeneous prestress therein;(3)The three earthquakes caused remarkable coseismic Coulomb stress changes at the subduction interface nearby these mainshocks,with an average Coulomb stress change of 3.2 bars in the shallow region directly inwards the trench. 展开更多
关键词 The 2020-2021 Alaska earthquake sequence Coseismic Coulomb stress change Mainshock-aftershock triggering The Alaska-Aleutian subduction interface The Shumagin gap
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Intelligent extraction of road cracks based on vehicle laser point cloud and panoramic sequence images
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作者 Ming Guo Li Zhu +4 位作者 Ming Huang Jie Ji Xian Ren Yaxuan Wei Chutian Gao 《Journal of Road Engineering》 2024年第1期69-79,共11页
In light of the limited efficacy of conventional methods for identifying pavement cracks and the absence of comprehensive depth and location data in two-dimensional photographs,this study presents an intelligent strat... In light of the limited efficacy of conventional methods for identifying pavement cracks and the absence of comprehensive depth and location data in two-dimensional photographs,this study presents an intelligent strategy for extracting road cracks.This methodology involves the integration of laser point cloud data obtained from a vehicle-mounted system and a panoramic sequence of images.The study employs a vehicle-mounted LiDAR measurement system to acquire laser point cloud and panoramic sequence image data simultaneously.A convolutional neural network is utilized to extract cracks from the panoramic sequence image.The extracted sequence image is then aligned with the laser point cloud,enabling the assignment of RGB information to the vehicle-mounted three dimensional(3D)point cloud and location information to the two dimensional(2D)panoramic image.Additionally,a threshold value is set based on the crack elevation change to extract the aligned roadway point cloud.The three-dimensional data pertaining to the cracks can be acquired.The experimental findings demonstrate that the use of convolutional neural networks has yielded noteworthy outcomes in the extraction of road cracks.The utilization of point cloud and image alignment techniques enables the extraction of precise location data pertaining to road cracks.This approach exhibits superior accuracy when compared to conventional methods.Moreover,it facilitates rapid and accurate identification and localization of road cracks,thereby playing a crucial role in ensuring road maintenance and traffic safety.Consequently,this technique finds extensive application in the domains of intelligent transportation and urbanization development.The technology exhibits significant promise for use in the domains of intelligent transportation and city development. 展开更多
关键词 Road crack extraction Vehicle laser point cloud Panoramic sequence images Convolutional neural network
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Influence of Production Sequence of Aluminum Alloy Hot Rolling on Strip Surface Quality
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作者 Hui Song Weixuan Jiang 《Frontiers of Metallurgical Industry》 2024年第1期12-14,共3页
With the intensification of market competition in the aluminum alloy strip processing industry,it is dif-ficult to control the mass production of the same specifications,which is bound to affect the hot rolling produc... With the intensification of market competition in the aluminum alloy strip processing industry,it is dif-ficult to control the mass production of the same specifications,which is bound to affect the hot rolling production.This paper studied the effect of the hot rolling order of aluminum alloy on the surface quality of strip,such as roll printing,color difference,anodic oxidation,etc.,reasonable discharge sequence and corresponding optimization measures were formulated. 展开更多
关键词 hot rolling production sequence surface quality aluminum alloy chromate treatment
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基于修正Park-Ang模型的SCS剪力墙损伤指数研究
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作者 彭修宁 李新宇 +1 位作者 林焯铭 杨旭杰 《地震工程与工程振动》 CSCD 北大核心 2023年第1期34-42,共9页
为研究双钢板混凝土组合剪力墙(Steel-concrete-steel composite shear walls,SCS)剪力墙在地震作用下的损伤演化规律,基于Park-Ang损伤模型提出修正后的SCS剪力墙双参数损伤模型,并采用OpenSees有限元软件对72个依照现行规范设计的SCS... 为研究双钢板混凝土组合剪力墙(Steel-concrete-steel composite shear walls,SCS)剪力墙在地震作用下的损伤演化规律,基于Park-Ang损伤模型提出修正后的SCS剪力墙双参数损伤模型,并采用OpenSees有限元软件对72个依照现行规范设计的SCS剪力墙试件进行分析,研究轴压比、剪跨比、暗柱配钢率、墙身配钢率对SCS剪力墙的极限位移、屈服位移、屈服剪力、累积滞回耗能等指标的影响,得到了适用于双钢板混凝土剪力墙基于变形和耗能双重准则的损伤模型。以对数正态分布作为分布密度函数来对双钢板混凝土剪力墙构件各损伤状态的累积概率密度进行拟合,得到了SCS剪力墙不同损伤程度对应的损伤指数范围。 展开更多
关键词 scs剪力墙 损伤模型 有限元分析 滞回曲线 损伤指数
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基于耦合PLUS-SCS模型的城市用地内涝风险预测及优化管控——以湖南省长沙市为例
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作者 焦胜 操婷婷 +1 位作者 牛彦合 关惠嫦 《水土保持通报》 CSCD 北大核心 2023年第5期195-202,共8页
[目的]预测城市未来土地利用情况及内涝风险强度,并探讨未来城市内涝风险的优化管控措施及实施效果,为提升城市内涝防控水平,优化城市用地布局提供参考依据。[方法]以湖南省长沙市为例,借助PLUS和SCS模型,预测基准情景下城市用地布局及... [目的]预测城市未来土地利用情况及内涝风险强度,并探讨未来城市内涝风险的优化管控措施及实施效果,为提升城市内涝防控水平,优化城市用地布局提供参考依据。[方法]以湖南省长沙市为例,借助PLUS和SCS模型,预测基准情景下城市用地布局及其内涝风险情况,将内涝高风险区域作为PLUS模型中的限制转化因子,耦合PLUS和SCS模型,模拟内涝管控情景下城市用地布局及其内涝风险情况。通过对比两种情景下的内涝风险差异来验证优化管控措施实施的效益。[结果]预测基准情景下2035年长沙市建设用地内涝高风险区面积为96.47 km^(2),在不减少建设用地面积的前提下,内涝管控情景下城市建设用地的内涝风险总面积相比基准情景减少了36.94 km^(2),其中新增建设用地中的高风险区全部被规避。[结论]未来城市用地内涝风险呈现出显著增加的趋势,耦合PLUS-SCS模型的优化管控方法能够帮助城市规避内涝风险。 展开更多
关键词 内涝风险预测 风险优化管控 PLUS模型 scs模型 未来情景模拟 湖南省长沙市
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基于SCS的四川省高速公路沿线山洪预警模型
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作者 褚永彬 杨国彬 +1 位作者 杨泓 宋扬 《测绘与空间地理信息》 2023年第10期7-9,共3页
山洪是汛期多发地质灾害之一。受地形和气候的影响,西南地区高速公路沿线易受山洪威胁。为了更好地防范山洪灾害,保障交通安全,基于SCS模型推导了流域产生径流的临界雨量模型。以四川省高速公路沿线小流域为研究区,利用土地利用类型数... 山洪是汛期多发地质灾害之一。受地形和气候的影响,西南地区高速公路沿线易受山洪威胁。为了更好地防范山洪灾害,保障交通安全,基于SCS模型推导了流域产生径流的临界雨量模型。以四川省高速公路沿线小流域为研究区,利用土地利用类型数据、土壤属性数据及降水数据等资料,计算得到了四川省高速公路沿线小流域发生山洪灾害的临界雨量。计算结果显示,四川省高速公路沿线流域的临界雨量在14—26 mm之间。与山洪灾害历史数据对比结果表明,模型预测效果良好。 展开更多
关键词 山洪 临界雨量 scs模型 高速公路
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基于SCS的多星联合诱导式欺骗检测算法 被引量:1
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作者 朱瑞晨 王文益 《现代电子技术》 2023年第11期1-8,共8页
欺骗式干扰严重威胁卫星导航接收机的信息安全,其中诱导式欺骗干扰可以在不令目标接收机失锁的状态下,隐蔽地夺取跟踪环路的控制权,加大了检测欺骗的难度。此外,多径干扰可能会造成基于信号质量监测(SQM)的欺骗检测算法虚警。文中提出... 欺骗式干扰严重威胁卫星导航接收机的信息安全,其中诱导式欺骗干扰可以在不令目标接收机失锁的状态下,隐蔽地夺取跟踪环路的控制权,加大了检测欺骗的难度。此外,多径干扰可能会造成基于信号质量监测(SQM)的欺骗检测算法虚警。文中提出一种基于S曲线过零点斜率(SCS)的多星联合欺骗检测算法,通过检验接收机遭受欺骗攻击时不同方向卫星的一致性,区分多径干扰与欺骗攻击。分别使用美国德州大学实采欺骗信号数据集(TEXBAT)与卫星信号模拟器生成的含有多径干扰的卫星信号进行实验分析。实验结果表明,所提出算法检测诱导式欺骗攻击时响应迅速,欺骗检测性能相较于三种传统的SQM算法更优,同时对于多径干扰有较强的鲁棒性。 展开更多
关键词 卫星导航 诱导式欺骗 scs 欺骗检测 多星联合检测 多径干扰 信号质量监测
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热解兰炭(SCs)基活性炭高效吸附SCs废水中苯酚的动力学和热力学
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作者 杨婷婷 卢翠英 +3 位作者 曹元甲 张智文 王震 马强 《材料科学与工程学报》 CAS CSCD 北大核心 2023年第6期974-983,共10页
以神府煤田盛产的优质侏罗精煤中低温热解兰炭(SCs)为原料,KOH活化制备了SACs,研究了用于去除SCs废水中苯酚的热力学和动力学。采用比表面积测试(BET)分析、扫描电镜(SEM)观察、傅里叶红外光谱(FTIR)和X射线衍射(XRD)测试对SACs进行了... 以神府煤田盛产的优质侏罗精煤中低温热解兰炭(SCs)为原料,KOH活化制备了SACs,研究了用于去除SCs废水中苯酚的热力学和动力学。采用比表面积测试(BET)分析、扫描电镜(SEM)观察、傅里叶红外光谱(FTIR)和X射线衍射(XRD)测试对SACs进行了微结构、形貌和表面官能团的表征。结果表明,KOH/SCs的质量比和热解温度是影响ASACs性能的主要因素。随着KOH/SCs质量比的增加和热解温度的升高,样品的比表面积先增大后减小。850℃,KOH/SCs质量比为4∶1时制备出具有丰富微孔的ASAC4,其比表面积为1689 m^(2)/g,孔体积为0.75 cm^(3)/g,平均孔径为1.81 nm,室温下,其对苯酚的最大吸附量为220.13 mg/g。动力学和热力学分析发现吸附是自发放热过程,符合准二级吸附动力学模型和Langmuir等温吸附模型,SCs去灰后制备的多孔材料吸附苯酚能力增强了25.87%。 展开更多
关键词 scs基SACs 吸附 苯酚 热力学和动力学
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SUBSTITUENT CHEMICAL SHIFT (SCS) AND THE SEQUENCE STRUCTURE OF ETHYLENE-VINYL ALCOHOL COPOLYMERS
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作者 周子南 田文晶 +4 位作者 吴盛容 戴莹琨 冯之榴 沈联芳 袁汉珍 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1992年第4期299-303,共5页
Three ethylene-vinyl alcohol copolymers were studied by means of the substituent chemical shift (SCS) method. The SCS parameters of hydroxy (-OH) in two different solvents were obtained: in deuterium oxide/phenol (20/... Three ethylene-vinyl alcohol copolymers were studied by means of the substituent chemical shift (SCS) method. The SCS parameters of hydroxy (-OH) in two different solvents were obtained: in deuterium oxide/phenol (20/80 W/W ) the parameters are S_1 = 42.77±0.08ppm, S_2 = 7.15±0.06 ppm, S_3 (s)= -4.08±0.02ppm, S_3 (t) =-3.09±0.20ppm,S_4 = 0.48±0.03ppm, S_5 = 0.26±0.05ppm. In o-dichloro-benzen-d_4 S_1(s)=44.79±0.61ppm, S_2=7.40±0.00ppm, S_3(s)=-4.51±0.17ppm, S_3(t)=-3.13 ±0.00 ppm, S_4 =0.63±0.04ppm, S_5=0.36±0.00ppm.Simultaneously the ^(13)CNMR spectra of EVA copolymers were assigned by using the SCS parameters obtained. 展开更多
关键词 Ethylene-α-olefine copolymers sequence structure Substituent chemical shift (scs) ^(13)C NMR.
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滇池西岸山地区域SCS-CN模型优化 被引量:1
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作者 李金梅 周京春 王金亮 《水土保持通报》 CSCD 北大核心 2023年第3期139-147,158,共10页
[目的]模拟计算滇池西岸山洪产流量,为该区面山截洪设施的修建,减少山洪灾害和保护滇池水环境提供科学决策的依据。[方法]基于SCS-CN产流模型,选取昆明滇池西岸山地区域2019,2020年的33场实测降雨径流数据,通过坡度结合前期影响雨量对C... [目的]模拟计算滇池西岸山洪产流量,为该区面山截洪设施的修建,减少山洪灾害和保护滇池水环境提供科学决策的依据。[方法]基于SCS-CN产流模型,选取昆明滇池西岸山地区域2019,2020年的33场实测降雨径流数据,通过坡度结合前期影响雨量对CN值进行分级优化设定。采用穷举法对λ进行优化取值。再以2021年的19场实测降雨径流数据验证优化SCS-CN模型的模拟精度及其参数适用性。[结果]①采用坡度及前期影响雨量分级优化得到的CN值仅适用于降雨量<30 mm的中小型降雨;对于降雨量≥30 mm的强降雨,需根据场次降雨前5 d的降雨总量采用线性内插法对标准SCS-CN模型中AMC等级进行修改,再确定对应的坡度CN修正值。②适合滇池西岸山地区域中小型降雨和强降雨的最佳初损系数λ值分别为0.15,0.2。③经验证,中小型降雨和强降雨下的NSE值分别为0.8522,0.7978,模型合格率分别为93.33%和75%。[结论]优化的SCS-CN模型用于滇池西岸山地区域<30 mm的中小型降雨和≥30 mm的强降雨情况下的产流计算是可行的,可为该区地表径流预测及SCS-CN模型的进一步优化提供科学依据和理论参考。 展开更多
关键词 山洪 地表径流 scs-CN模型 径流曲线数CN 初损系数λ
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Improving the accuracy of genomic prediction for meat quality traits using whole genome sequence data in pigs 被引量:1
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作者 Zhanwei Zhuang Jie Wu +14 位作者 Yibin Qiu Donglin Ruan Rongrong Ding Cineng Xu Shenping Zhou Yuling Zhang Yiyi Liu Fucai Ma Jifei Yang Ying Sun Enqin Zheng Ming Yang Gengyuan Cai Jie Yang Zhenfang Wu 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第5期1880-1894,共15页
Background Pork quality can directly affect customer purchase tendency and meat quality traits have become valu-able in modern pork production.However,genetic improvement has been slow due to high phenotyping costs.In... Background Pork quality can directly affect customer purchase tendency and meat quality traits have become valu-able in modern pork production.However,genetic improvement has been slow due to high phenotyping costs.In this study,whole genome sequence(WGS)data was used to evaluate the prediction accuracy of genomic best linear unbiased prediction(GBLUP)for meat quality in large-scale crossbred commercial pigs.Results We produced WGS data(18,695,907 SNPs and 2,106,902 INDELs exceed quality control)from 1,469 sequenced Duroc×(Landrace×Yorkshire)pigs and developed a reference panel for meat quality including meat color score,marbling score,L*(lightness),a*(redness),and b*(yellowness)of genomic prediction.The prediction accuracy was defined as the Pearson correlation coefficient between adjusted phenotypes and genomic estimated breeding values in the validation population.Using different marker density panels derived from WGS data,accuracy differed substantially among meat quality traits,varied from 0.08 to 0.47.Results showed that MultiBLUP outperform GBLUP and yielded accuracy increases ranging from 17.39%to 75%.We optimized the marker density and found medium-and high-density marker panels are beneficial for the estimation of heritability for meat quality.Moreover,we conducted genotype imputation from 50K chip to WGS level in the same population and found average concord-ance rate to exceed 95%and r^(2)=0.81.Conclusions Overall,estimation of heritability for meat quality traits can benefit from the use of WGS data.This study showed the superiority of using WGS data to genetically improve pork quality in genomic prediction. 展开更多
关键词 Genomic prediction Meat quality PIGS Whole genome sequence
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A Novel Method of Deinterleaving Radar Pulse Sequences Based on a Modified DBSCAN Algorithm 被引量:1
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作者 Abolfazl Dadgarnia Mohammad Taghi Sadeghi 《China Communications》 SCIE CSCD 2023年第2期198-215,共18页
A modified DBSCAN algorithm is presented for deinterleaving of radar pulses in modern EW environments.A main characteristic of the proposed method is that using only time of arrival of pulses,the method can sort the p... A modified DBSCAN algorithm is presented for deinterleaving of radar pulses in modern EW environments.A main characteristic of the proposed method is that using only time of arrival of pulses,the method can sort the pulses efficiently.Other PDW information such as rise time,carrier frequency,pulse width,modulation on pulse,fall time and direction of arrival are not required.To identify the valid PRIs in a set of interleaved pulses,an innovative modification of the DBSCAN algorithm is introduced which is accurate and easy to implement.The proposed method determines valid PRIs more accurately and neglects the spurious ones more efficiently as compared to the classical histogram based algorithms such as SDIF.Furthermore,without specifying any input parameter,the proposed method can deinterleave radar pulses while up to 30%jitter is present in the associated PRI.The accuracy and efficiency of the proposed method are verified by computer simulations and real data results.Experimental simulations are based on different real and operational scenarios where the presence of missing and spurious pulses are also considered.So,the simulation results can be of practical significance. 展开更多
关键词 DEINTERLEAVING radar pulse sequences density based clustering pulse descriptor word
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PRI modulation recognition and sequence search under small sample prerequisite 被引量:2
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作者 ZHANG Chunjie LIU Yuchen SI Weijian 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第3期706-713,共8页
Pulse repetition interval(PRI)modulation recognition and pulse sequence search are significant for effective electronic support measures.In modern electromagnetic environments,different types of inter-pulse slide rada... Pulse repetition interval(PRI)modulation recognition and pulse sequence search are significant for effective electronic support measures.In modern electromagnetic environments,different types of inter-pulse slide radars are highly confusing.There are few available training samples in practical situations,which leads to a low recognition accuracy and poor search effect of the pulse sequence.In this paper,an approach based on bi-directional long short-term memory(BiLSTM)networks and the temporal correlation algorithm for PRI modulation recognition and sequence search under the small sample prerequisite is proposed.The simulation results demonstrate that the proposed algorithm can recognize unilinear,bilinear,sawtooth,and sinusoidal PRI modulation types with 91.43% accuracy and complete the pulse sequence search with 30% missing pulses and 50% spurious pulses under the small sample prerequisite. 展开更多
关键词 inter-pulse slide pulse repetition interval(PRI)modulation type bi-directional long short-term memory(BiLSTM)network sequence search
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