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Characteristics of long-distance mobile mRNAs from shoot to root in grafted plant species
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作者 Mengmeng Fu Zhen Xu +7 位作者 Huaying Ma Yifan Hao Ji Tian Yi Wang Xinzhong Zhang Xuefeng Xu Zhenhai Han Ting Wu 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第1期25-37,共13页
Thousands of long-distance mobile mRNAs were identified from different grafting systems,based on high-throughput sequencing technology.Moreover,the long-distance delivery of RNAs was proved to involve multiple mechani... Thousands of long-distance mobile mRNAs were identified from different grafting systems,based on high-throughput sequencing technology.Moreover,the long-distance delivery of RNAs was proved to involve multiple mechanisms.Here,we analyzed the homology,motif,and tRNA-like structure(TLS)of long-distance mobile mRNAs identified by RNA-seq as well as the RNA-binding protein(RBP)in nine grafting combinations including Arabidopsis thaliana,Vitis vinifera,Cucumis sativus,Citrullus lanatus,Nicotiana benthamiana,Malus domestica,Pyrus spp.,Glycine max and Phaseolus vulgaris.Although several mRNAs were found to be shared in herbaceous,woody,and related species,the vast majority of long-distance mobile mRNAs were species-specific.Four non-specific movement-related motifs were identified,while the TLS was not necessary for mRNA long distance mobility.In addition,we found that RBPs were conserved among herbaceous and woody plants as well as related species.This paper reports a further in-depth analysis of the endogenous mechanisms by which the species-specific transportable m RNAs were selected by bioinformatics,in order to provide insights for future research on long-distance mobile mRNAs. 展开更多
关键词 Grafting combination long-distance mobile mRNA TLS RNA binding proteins
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Water hammer protection for diversion systems in front of pumps in long-distance water supply projects 被引量:4
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作者 Lin Shi Jian Zhang +3 位作者 Xiao-dong Yu Sheng Chen Wen-long Zhao Xu-yun Chen 《Water Science and Engineering》 EI CAS CSCD 2023年第2期211-218,共8页
For a water supply system with long-distance diversion pipelines, in addition to the water hammer problems that occur beyond pumps, the safety of the water diversion pipeline in front of pumps also deserves attention.... For a water supply system with long-distance diversion pipelines, in addition to the water hammer problems that occur beyond pumps, the safety of the water diversion pipeline in front of pumps also deserves attention. In this study, a water hammer protection scheme combined with an overflow surge tank and a regulating valve was developed. A mathematical model of the overflow surge tank was developed, and an analytical formula for the height of the overflow surge tank was derived. Furthermore, a practical water supply project was used to evaluate the feasibility of the combined protection scheme and analyze the sensitivity of valve regulation rules. The results showed that the combined protection scheme effectively reduced the height of the surge tank, lessened the difficulties related to construction, and reduced the necessary financial investment for the project. The two-stage closing rule articulated as fast first and then slow could minimize the overflow volume of the surge tank when the power failure occurred, while the two-stage opening rule articulated as slow first and then fast could be more conducive to the safety of the water supply system when the pump started up. 展开更多
关键词 long-distance diversion pipeline Water supply Water hammer Overflow surge tank Regulating valve
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线上中文学习平台Lingo Bus和Lingo Ace比较研究
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作者 李萌 吴应辉 《海南师范大学学报(社会科学版)》 2024年第1期101-108,共8页
Lingo Bus和Lingo Ace平台是当前受到市场青睐的知名线上中文学习平台。对两个学习平台的建设、教学和管理营销三个方面的情况进行比较研究后发现:两个平台均通过线上直播课程面向海外青少儿教授中文,均建立了各自的官网和客户端,在品... Lingo Bus和Lingo Ace平台是当前受到市场青睐的知名线上中文学习平台。对两个学习平台的建设、教学和管理营销三个方面的情况进行比较研究后发现:两个平台均通过线上直播课程面向海外青少儿教授中文,均建立了各自的官网和客户端,在品牌定位、课程资源体系、选课方式和学习者服务模式等方面的设计上都有差异,针对教师选拔、培训的侧重点和严格程度也有不同的标准;两个平台均注重通过口碑、新闻软文和社交媒体等途径进行营销,但在推广方式和营销经费投入力度方面做法不同。线上中文学习平台应建设本土化和标准化教学资源,提升系统稳定性和智能化水平,完善教师管理机制,建立良好服务体系,组建本土团队,实施精准营销等发展策略。 展开更多
关键词 中文学习平台 Lingo bus Lingo Ace 数字中文教育
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Factors Influence Hanoians’ Choice of Non-Motorized Transport Mode to Access Bus Stations
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作者 Ngo Trung Phuong Masahiko Kikuchi +1 位作者 Aya Kojima Hisashi Kubota 《Journal of Transportation Technologies》 2024年第3期372-389,共18页
Hanoi’s rapid urbanization has led to a surge in private vehicle ownership, particularly motorcycles, amidst inadequate public transportation infrastructure. Despite government efforts, many still prefer motorized tr... Hanoi’s rapid urbanization has led to a surge in private vehicle ownership, particularly motorcycles, amidst inadequate public transportation infrastructure. Despite government efforts, many still prefer motorized transport, citing mobility and safety concerns, exacerbated by insufficient pedestrian infrastructure. This study examines the motivations behind this reliance on motorized vehicles, particularly motorcycles, in Hanoi. Findings reveal safety and convenience as primary factors driving motorized transport use, especially for accessing bus stations. Economic incentives could promote non-motorized travel and public transport adoption. Policy implications highlight the importance of addressing economic factors and improving access infrastructure to manage motorized vehicle reliance and foster sustainable urban mobility in Hanoi. 展开更多
关键词 Access Mode Choice Non-Motorized Vehicles Motorized Vehicles bus User Urban Transport Behavior
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Charging Ahead with E-Buses: Benefits, Costs, and Transition Roadmap
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作者 Aaron Yang Katherine Wan Angela Fanqi Jin 《Open Journal of Applied Sciences》 2024年第9期2717-2748,共32页
This paper reaches a recommendation for the 10-year e-bus transition roadmap for New York City. The lifecycle model of emission reduction demonstrates the ecological and financial impacts of a complete transition from... This paper reaches a recommendation for the 10-year e-bus transition roadmap for New York City. The lifecycle model of emission reduction demonstrates the ecological and financial impacts of a complete transition from the current diesel bus fleet to an all-electric bus fleet in New York City by 2033. This study focuses on the NOx pollution, which is the highest among all major cities by Environmental Protection Agency (EPA) and greenhouse gases (GHG) with annual emissions of over five million tons. Our model predicts that switching to an all-electric bus fleet will cut GHG emissions by over 390,000 tons and NOx emissions by over 1300 tons annually, in addition to other pollutants such as VOCs and PM 2.5. yielding an annual economic benefit of over 75.94 million USD. This aligns with the city mayor office’s initiative of achieving total carbon neutrality. We further model an optimized transition roadmap that balances ecological and long-term benefits against the costs of the transition, emphasizing feasibility and alignment with the natural replacement cycle of existing buses, ensuring a steady budgeting pattern to minimize interruptions and resistance. Finally, we advocate for collaboration between government agencies, public transportation authorities, and private sectors, including electric buses and charging facility manufacturers, which is essential for fostering innovation and reducing the costs associated with the transition to e-buses. 展开更多
关键词 City Electric bus Greenhouse Gas Emission Reduction Economic Analysis Optimization Model Total Cost of Ownership
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Simulation of long-distance pipeline transportation properties of whole-tailings paste with high sliming 被引量:18
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作者 WU Ai-xiang RUAN Zhu-en +4 位作者 WANG Yi-ming YIN Sheng-hua WANG Shao-yong WANG Yong WANG Jian-dong 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第1期141-150,共10页
Based on Bingham rheological model,a three-dimensional numerical simulation model for long-distance pipeline transportation is established by computational fluid dynamics(CFD)to study the pipeline transportationproper... Based on Bingham rheological model,a three-dimensional numerical simulation model for long-distance pipeline transportation is established by computational fluid dynamics(CFD)to study the pipeline transportationproperties of high sliming paste from a copper mine in China.Based on the rheological properties test,the pressure and velocity of pipeline and elbow are simulated by CFD under different mass concentrations and different stowing capacities.The results show that the pipeline resistance of whole-tailings paste with high sliming while without pumping agent is much higher than that with high sliming and pumping agent at the same mass concentration,and the pipeline resistance of whole-tailings paste with high sliming while without pumping agent is much higher than that with low sliming while without pumping agent.It is very important to add pumping agent to whole-tailings paste with high sliming,and the resistance changes with mass concentration and stowing capacity at the same cement-to-sand ratio of1:5and tailings-to-waste ratio of6:1.However,the change is just limited,that is to say,the paste transportation system is of good stability.Furthermore,at the elbow,the maximum pressure and velocity transfer to the outside of the pipe from the inside.However,lubricating layer is formed at the pipe wall because of high content of fine particles in whole-tailings paste,which will protect the elbow from abrasion.CFD provides an intuitive and accurate basis for pipeline transportation study,and would have a wider application space in the study of paste rheological properties and resistance reduction methods. 展开更多
关键词 whole-tailings paste long-distance transportation computational fluid dynamics
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Study on the Technology of Supplying Water Safely by Long-Distance Pipeline 被引量:3
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作者 CHEN Yanbo YU Taipin +1 位作者 LIU Junhua ZHAO Hongbin 《Journal of Northeast Agricultural University(English Edition)》 CAS 2008年第3期80-85,共6页
The extensively built long-distance water transmission pipelines have become the main water sources for urban areas. To ensure the reliability and safety of the water supply, from the viewpoint of overall management, ... The extensively built long-distance water transmission pipelines have become the main water sources for urban areas. To ensure the reliability and safety of the water supply, from the viewpoint of overall management, it would be necessary to establish a system of information management for the pipeline. The monitoring, calculating and analyzing functions of the system serve to give controlling instructions and safe operating rules to the automatic equipment and technician, making sure the resistance coefficient distribution along the pipeline is reasonable; the hydraulic state transition is smooth when operating conditions change or water supply accidents occur, avoiding the damage of water hammer. This paper covered the composition structures of the information management system of long-distance water transmission pipelines and the functions of the subsystems, and finally elaborated on the approaches and steps of building a mathematics model for the analysis of dynamic hydraulic status. 展开更多
关键词 long-distance water transmission pipeline water supply security information management water hammer MODELING
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Study on the long-distance target apperception techniques for underwater vehicles 被引量:2
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作者 Yang Xudong Huang Jianguo Zhang Qunfei Tang Qi 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第3期484-490,共7页
The limited physical size for autonomous underwater vehicles (AUV) or unmanned underwater vehicles (UUV) makes it difficult to acquire enough space gain for localizing long-distance targets. A new technique about ... The limited physical size for autonomous underwater vehicles (AUV) or unmanned underwater vehicles (UUV) makes it difficult to acquire enough space gain for localizing long-distance targets. A new technique about long-distance target apperception with passive synthetic aperture array for underwater vehicles is presented. First, a synthetic aperture-processing algorithm based on the FFT transform in the beam space (BSSAP) is introduced. Then, the study on the flank array passive long-distance apperception techniques in the frequency scope of 11-18 kHz is implemented from the view of improving array gains, detection probability and augmenting detected range under a certain sea environment. The results show that the BSSAP algorithm can extend the aperture effectively and improve detection probability. Because of the augment of the transmission loss, the detected range has the trend of decline with the increase of frequency under the same target source level. The synthesized array could improve the space gain by nearly 7 dB and SNR is increased by about 5 dB. The detected range is enhanced to nearly 2 km under the condition of 108-118 dB of the target source level for AUV system in measurement interval of nearly 1 s. 展开更多
关键词 long-distance apperception synthetic aperture processing array gain detection probability detectedrange.
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Long-distance propagation of pseudo-partially coherent Gaussian Schell-model beams in atmospheric turbulence 被引量:2
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作者 钱仙妹 朱文越 饶瑞中 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第9期259-266,共8页
Propagation properties of spatially pseudo-partially coherent Gaussian Schell-model beams through the atmo- spheric turbulence over a long-distance uplink path are studied by numerical simulation. A linear coordinatio... Propagation properties of spatially pseudo-partially coherent Gaussian Schell-model beams through the atmo- spheric turbulence over a long-distance uplink path are studied by numerical simulation. A linear coordination trans- formation is introduced to overcome the window effect and the loss-of-resolution problem. The beam spreading, beam wandering, and intensity scintillation as functions of turbulence strength, source correlation length, and change fre- quency of random phase that models the partial coherence of the source are analyzed. It is found that the beam spreading and the intensity scintillation of the partially coherent beam are less affected by the turbulence than those of the coherent one, but it suffers from a more severe diffractive effect, and the change frequency of random phase has no evident influence on it. The beam wandering is insensitive to the variation of source correlation length, and decreases firstly then goes to a fixed value as the change frequency increases. 展开更多
关键词 long-distance propagation pseudo-partially coherent Caussian Schell-model beam at-mospheric turbulence numerical simulation
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Improvement of heat-tolerance by training I. Evaluation of effects of long-distance running and march training on heat-tolerance 被引量:1
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作者 邱仞之 甄洪钧 +3 位作者 朱受成 万为人 刘汉湘 华旭初 《Journal of Medical Colleges of PLA(China)》 CAS 1995年第3期220-226,共7页
in order to verify the heat-tolerance effect, two trainings, 90 min marching with load (WBGT 24. 6~35.6℃) and 10 km running (WBGT 25.0~31.1℃) were performed in laboratory and field under hot climate.Ten to twelve ... in order to verify the heat-tolerance effect, two trainings, 90 min marching with load (WBGT 24. 6~35.6℃) and 10 km running (WBGT 25.0~31.1℃) were performed in laboratory and field under hot climate.Ten to twelve times (days) of training were carried out 展开更多
关键词 MARCH long-distance running TRAINING HEAT ACCLIMATIZATION heat-tolerance infantryman
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Influencing Factors of Seed Long-distance Dispersal on a Fragmented Forest Landscape on Changbai Mountains,China 被引量:1
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作者 ZHAO Fuqiang QI Lin +1 位作者 FANG Lei YANG Jian 《Chinese Geographical Science》 SCIE CSCD 2016年第1期68-77,共10页
Seed long-distance dispersal(LDD) events are typically rare, but are important in the population processes that determine large-scale forest changes and the persistence of species in fragmented landscapes. However, pr... Seed long-distance dispersal(LDD) events are typically rare, but are important in the population processes that determine large-scale forest changes and the persistence of species in fragmented landscapes. However, previous studies focused on species dispersed via animal-mediated LDD, and ignored those dispersed by wind. The aim of this study was to assess the effects of canopy openness, edge, seed source, and patch tree density on the LDD of seeds by wind in forest. We collected birch seeds, a typical wind-dispersed species, throughout a larch plantation. We then assessed the relationship between birch LDD and each factor that may influence LDD of seeds by wind including distance to edge, canopy openness size, distance to mature forest, and the tree density of the larch plantation. We used univariate linear regression analysis to assess the influence of those factors on birch LDD, and partial correlations to calculate the contribution of each factor to LDD. The results showed that both canopy openness and edge had significant influences on birch LDD. Specifically, a negative relationship was observed between distance to edge and birch LDD, whereas there was a positive correlation between canopy openness size and LDD. In contrast, the distance to the mature forest was not correlated with birch LDD. Our results suggest that patch tree density could potently affect the probability of LDD by wind vectors, which provides novel and revealing insights regarding the effect of fragmentation on wind dynamics. The data also provide compelling evidence for the previously undocumented effect of habitat fragmentation on wind-dispersed organisms. As such, these observations will facilitate reasonable conservation planning, which requires a detailed understanding of the mechanisms by which patch properties hamper the delivery of seeds of wind-dispersed plants to fragmented areas. 展开更多
关键词 seed long-distance dispersal (LDD) forest fragmentation patch property wind dispersal Changbai Mountains
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Criterions and Measures of Route Selection of Shallowly Embedded Long-Distance Oil and Gas Pipeline in Mountain Areas 被引量:1
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作者 WANG Chenghua MA Qingwen +2 位作者 KONG Jiming CHEN Zefu LI Xiuzhen 《Wuhan University Journal of Natural Sciences》 EI CAS 2006年第4期787-792,共6页
According to the engineering investigation of long-distance oil and gas pipelines, the criterions and measures of route selection are drawn as follows: the flat landform is the first choice in route alignment. The fo... According to the engineering investigation of long-distance oil and gas pipelines, the criterions and measures of route selection are drawn as follows: the flat landform is the first choice in route alignment. The foot of mountain is the first choice when the route passes by the valley. The route should pass by but the shady and deposited slope and not in sunny and erosive slope as possible as it can. The pipeline should be vertical to contour climbing and descending the mountain except steep slope. Tunnel can be used in crossing foothill. Perpendicularly traversing the river is better than beveling; the worst choice is to put the pipeline along the river. Bypass is the best choice in karsts area. The order of route selection should be pre-choosing, investigation, optimization and adjustment. 展开更多
关键词 shallowly embedded long-distance oil and gas pipeline criterions and measures of route selection avoiding geological hazards
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THE RISK ASSESSMENT OF THE LONG-DISTANCE OILPIPELINE ENGINEERING
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作者 Wang Jinghua Mu Congru(Institute of Geography, CAS, Beijing 100101People’s Republic of China) 《Journal of Geographical Sciences》 SCIE CSCD 1996年第1期78-83,共6页
The oilfield construction and long-distance oil pipeline engineering has been developed extensively in China. The risk assessment of oil industry will, however, be an important objective to cope with the development o... The oilfield construction and long-distance oil pipeline engineering has been developed extensively in China. The risk assessment of oil industry will, however, be an important objective to cope with the development of oil industry , The risk assessment of oil industry has many subjects worthy to be studied.The major purpose of the paper is to research the risk cases of long-distance oil pipeline engineering in Ganshu and Shaanxi provinces. 展开更多
关键词 long-distance oil pipeline risk assessment ENGINEERING GANSU SHAANXI
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Long-distance super-exchange and quantum magnetic relaxation in a hybrid metal–organic framework
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作者 田英 申世鹏 +3 位作者 丛君状 闫丽琴 柴一晟 孙阳 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第1期390-393,共4页
The hybrid metal-organic framework [(CH3)2NH2]Fe(HCOO)3 with a perovskite-like structure exhibits a variety of unusual magnetic behaviors at low temperatures. While the long-distance super-exchange through the Fe-... The hybrid metal-organic framework [(CH3)2NH2]Fe(HCOO)3 with a perovskite-like structure exhibits a variety of unusual magnetic behaviors at low temperatures. While the long-distance super-exchange through the Fe-(Y-CH-O- Fe exchange path leads to a canted antiferromagnetic ordering at TN - 19 K, a second transition of magnetic blocking develops at TB- 9 K. The stair-shaped magnetization hysteresis loops below TB resemble the behaviors of resonant quantum tunneling of magnetization in single-molecular quantum magnets. Moreover, the magnetic relaxation also exhibits several features of resonant quantum relaxation, such as the exponential law with a single characteristic relaxation time, and the nonmonotonic dependence of relaxation rate on the applied magnetic field with a much faster relaxation around the resonant fields. The origin of quantum tunneling behaviors in the [(CH3)2NH2]Fe(HCOO)3 metal-organic framework is discussed in terms of magnetic phase separation due to the modification of hydrogen bonding on the long-distance super-exchange interaction. 展开更多
关键词 metal-organic frameworks resonant quantum relaxation long-distance super-exchange interac- tion hydrogen bonds
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Point Cloud Based Semantic Segmentation Method for Unmanned Shuttle Bus 被引量:1
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作者 Sidong Wu Cuiping Duan +5 位作者 Bufan Ren Liuquan Ren Tao Jiang Jianying Yuan Jiajia Liu Dequan Guo 《Intelligent Automation & Soft Computing》 SCIE 2023年第9期2707-2726,共20页
The complexity of application scenarios and the enormous volume of point cloud data make it difficult to quickly and effectively segment the scenario only based on the point cloud.In this paper,to address the semantic... The complexity of application scenarios and the enormous volume of point cloud data make it difficult to quickly and effectively segment the scenario only based on the point cloud.In this paper,to address the semantic segmentation for safety driving of unmanned shuttle buses,an accurate and effective point cloud-based semantic segmentation method is proposed for specified scenarios(such as campus).Firstly,we analyze the characteristic of the shuttle bus scenarios and propose to use ROI selection to reduce the total points in computation,and then propose an improved semantic segmentation model based on Cylinder3D,which improves mean Intersection over Union(mIoU)by 1.3%over the original model on SemanticKITTI data;then,a semantic category division method is proposed for road scenario of shuttle bus and practical application requirements,and then we further simplify the model to improve the efficiency without losing the accuracy.Finally,the nuScenes dataset and the real gathered campus scene data are used to validate and analyze the proposed method.The experimental results on the nuScenes dataset and our data demonstrate that the proposed method performs better than other point cloud semantic segmentation methods in terms of application requirements for unmanned shuttle buses.Which has a higher accuracy(82.73%in mIoU)and a higher computational efficiency(inference speed of 90 ms). 展开更多
关键词 Point cloud unmanned shuttle bus semantic segmentation
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A novel intrusion detection model for the CAN bus packet of in-vehicle network based on attention mechanism and autoencoder 被引量:1
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作者 Pengcheng Wei Bo Wang +2 位作者 Xiaojun Dai Li Li Fangcheng He 《Digital Communications and Networks》 SCIE CSCD 2023年第1期14-21,共8页
The attacks on in-vehicle Controller Area Network(CAN)bus messages severely disrupt normal communication between vehicles.Therefore,researches on intrusion detection models for CAN have positive business value for veh... The attacks on in-vehicle Controller Area Network(CAN)bus messages severely disrupt normal communication between vehicles.Therefore,researches on intrusion detection models for CAN have positive business value for vehicle security,and the intrusion detection technology for CAN bus messages can effectively protect the invehicle network from unlawful attacks.Previous machine learning-based models are unable to effectively identify intrusive abnormal messages due to their inherent shortcomings.Hence,to address the shortcomings of the previous machine learning-based intrusion detection technique,we propose a novel method using Attention Mechanism and AutoEncoder for Intrusion Detection(AMAEID).The AMAEID model first converts the raw hexadecimal message data into binary format to obtain better input.Then the AMAEID model encodes and decodes the binary message data using a multi-layer denoising autoencoder model to obtain a hidden feature representation that can represent the potential features behind the message data at a deeper level.Finally,the AMAEID model uses the attention mechanism and the fully connected layer network to infer whether the message is an abnormal message or not.The experimental results with three evaluation metrics on a real in-vehicle CAN bus message dataset outperform some traditional machine learning algorithms,demonstrating the effectiveness of the AMAEID model. 展开更多
关键词 Controller area network bus packet In-vehicle network Attention mechanism Autoencoder
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Estimation of the Probability of Long-Distance Dispersal: Stratified Diffusion of <i>Spartina alterniflora</i>in the Yangtze River Estuary
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作者 Wei Yang Qing Wang +1 位作者 Xiaoyun Pan Bo Li 《American Journal of Plant Sciences》 2014年第24期3642-3651,共10页
The relative contribution of long-distance dispersal and local diffusion in the spread of invasive species has been a subject of much debate. Invasion of the intertidal mudflats by Spartina alterniflora is an ideal ex... The relative contribution of long-distance dispersal and local diffusion in the spread of invasive species has been a subject of much debate. Invasion of the intertidal mudflats by Spartina alterniflora is an ideal example of stratified diffusion, involving both long-distance dispersal of seeds and local diffusion due to clonal growth. In conjunction with experimental data on range radius-versus-time curve, a traveling wave equation-based model is used to investigate the sensitivity of the spread rate of exotic S. alterniflora to parameters of long distance dispersal (c, maximum colonial establishment rate) and local colony diffusion (r, intrinsic growth rate) at two tidal marshes, the Eastern Chongming and the Jiuduansha Islands, at the Yangtze River estuary. Both Eastern Chong ming and Jiuduansha Islands are now national natural reserves in China, which were established in 2005. However, the mudflats and salt marshes in the two reserves are now heavily infested with introduced S. alterniflora, which may threaten the estuarine ecosystems and their biodiversity. S. alterniflora was first found in 1995 on Chongming. For rapid sediment accretion in mudflats in the estuary, S. alterniflora was also intentionally introduced to Jiuduansha in 1997 and Chongming in 2001, which has led to a rapid range expansion in the estuary. Our results show that range expansion of species with stratified diffusion is affected by both long-distance dispersal and local colony diffusion, and that there is a critical c*, below which the spread rate is more influenced by long-distance dispersal than by local diffusion. After applying this model to the invasion of S. alterniflora in the Yangtze River estuary, we derive that c = 1.7 × 10-3, c* = 0.126 and c = 4.8 × 10-3 km-2·yr-1, c* = 0.140 km-2·yr-1 at Chongming and Jiuduansha (Shanghai), respectively. Our results suggest that the range spread of S. alterniflora in the Yangtze River estuary is more influenced by long-distance dispersal than local colony diffusion, and that S. alterniflora generates about 1.7 × 10-3 to 4.8 × 10-3 colonies per square kilometers per year. This study provides important information about dispersal dynamics of S. alterniflora that may be useful for finding optimal control strategies. · 展开更多
关键词 long-distance Dispersal STRATIFIED DIFFUSION Sensitivity Analysis Traveling Wave Equation SPARTINA alterniflora
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High-Performance Sodium Bose-Einstein Condensate Apparatus with a Hybrid Trap and Long-Distance Magnetic Transfer
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作者 张峰 龙云 +3 位作者 杨江陵 马国强 殷冀平 王如泉 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第12期51-54,共4页
We report on the production of large sodium Bose^Einstein condensates in a hybrid of magnetic quadrupole and optical dipole trap. With an optimized spin-flip Zeeman slower, 2 ~ 1010 sodium atoms are captured in the ma... We report on the production of large sodium Bose^Einstein condensates in a hybrid of magnetic quadrupole and optical dipole trap. With an optimized spin-flip Zeeman slower, 2 ~ 1010 sodium atoms are captured in the magneto-optical trap (MOT). A long distance magnetic transfer setup moves the cold atom over 46cm from the MOT chamber to the UHV science chamber, which provides great optical access and long conservative trap lifetime. After evaporative cooling in the hybrid trap, we produce nearly pure condensates of 1 ~ 107 atoms with lifetime of 80 s in the optical dipole trap. 展开更多
关键词 MOT High-Performance Sodium Bose-Einstein Condensate Apparatus with a Hybrid Trap and long-distance Magnetic Transfer BEC
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Research on the Long-distance Transmission
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作者 Xueli Wu Xiuyuan Yang +1 位作者 Hong Shen Qinyong Zhou 《Energy and Power Engineering》 2013年第4期1293-1297,共5页
In view of the imbalanced distribution of power load and resources, including the status of “electric shortage” in some cities in our country, the article discusses the long-distance transmission technology. It main... In view of the imbalanced distribution of power load and resources, including the status of “electric shortage” in some cities in our country, the article discusses the long-distance transmission technology. It mainly analyzed two ways of the long-distance transmission: UHV AC transmission and UHV DC transmission. The fractional frequency transmission technology and half wavelength AC transmission technology of AC transmission are introduced. Some key technologies of long-distance transmission are described. It has a guess for long-distance transmission future direction. 展开更多
关键词 Energy long-distance Ultra-high VOLTAGE (UHV) ALTERNATING CURRENT (AC) Direct CURRENT (DC) TRANSMISSION
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Early Prevention of Exercise-induced Tibia Periostitis for Long-Distance Runners in China' s Regular Universities
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作者 Yajie Mao 《International English Education Research》 2014年第2期21-24,共4页
Exercise-induced tibia periostitis is one of the most common sports injuries in the sports training of athletics in regular institutions of higher learning. It often occurs. When it is serious, periosteal proliferatio... Exercise-induced tibia periostitis is one of the most common sports injuries in the sports training of athletics in regular institutions of higher learning. It often occurs. When it is serious, periosteal proliferation would occur, It will result in fatigue fi^cture sometimes. This is relevant to tibialis anterior muscle restrained contraction in the events in the sports process. If measures are not adopted, early prevention should be strengthened. This would not only affect seriously the sports achievement of long-distance runners, but also affects their future ordinary lives. Through analysis and summaries, the main reasons for the occurrence of tibia periostitis for long-distance runners are shown. From the perspectives of reasonably arranging the exercise load, strengthening the field management and strengthening the self-protection and so on, the prevention of tibia periostitis for long-distance runners has been explored. It also helps the long-distance runners to train scientifically, which can effectively avoid and lessen the occurrence of tibia periostitis and the adverse effect it brings. 展开更多
关键词 Regular Institutions of Higher Learning long-distance Runners Tibia Periostitis Early Prevention
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