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Industrial Carbon Emission Distribution and Regional Joint Emission Reduction:A Case Study of Cities in the Pearl River Basin,China 被引量:2
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作者 JIANG Hongtao YIN Jian +4 位作者 ZHANG Bin WEI Danqi LUO Xinyuan DING Yi XIA Ruici 《Chinese Geographical Science》 SCIE CSCD 2024年第2期210-229,共20页
China’s low-carbon development path will make significant contributions to achieving global sustainable development goals.Due to the diverse natural and economic conditions across different regions in China,there exi... China’s low-carbon development path will make significant contributions to achieving global sustainable development goals.Due to the diverse natural and economic conditions across different regions in China,there exists an imbalance in the distribution of car-bon emissions.Therefore,regional cooperation serves as an effective means to attain low-carbon development.This study examined the pattern of carbon emissions and proposed a potential joint emission reduction strategy by utilizing the industrial carbon emission intens-ity(ICEI)as a crucial factor.We utilized social network analysis and Local Indicators of Spatial Association(LISA)space-time trans-ition matrix to investigate the spatiotemporal connections and discrepancies of ICEI in the cities of the Pearl River Basin(PRB),China from 2010 to 2020.The primary drivers of the ICEI were determined through geographical detectors and multi-scale geographically weighted regression.The results were as follows:1)the overall ICEI in the Pearl River Basin is showing a downward trend,and there is a significant spatial imbalance.2)There are numerous network connections between cities regarding the ICEI,but the network structure is relatively fragile and unstable.3)Economically developed cities such as Guangzhou,Foshan,and Dongguan are in the center of the network while playing an intermediary role.4)Energy consumption,industrialization,per capita GDP,urbanization,science and techno-logy,and productivity are found to be the most influential variables in the spatial differentiation of ICEI,and their combination in-creased the explanatory power of the geographic variation of ICEI.Finally,through the analysis of differences and connections in urban carbon emissions under different economic levels and ICEI,the study suggests joint carbon reduction strategies,which are centered on carbon transfer,financial support,and technological assistance among cities. 展开更多
关键词 industrial carbon emission intensity carbon emission social network analysis location Indicators of Spatial Association(LISA) geographical detector multi-scale geographically weighted regression Pearl River Basin(PRB) China
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The First Reported Case of Co-Infection with Neisseria Meningitidis and Bordetella Pertussis in the Cerebrospinal Fluid Specimen of a Normal Four-Year-Old Child
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作者 XIA Xian LI Guo Ming +7 位作者 TANG Yi WANG Si Quan HE Fei JIANG Yong Zhong YANG Hong Mei JIANG Hong Lin LYU Jing MAO Ling Feng 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第4期432-435,共4页
Pertussis is an acute and highly contagious respiratory disease caused by Bordetella pertussis(B.pertussis),which occurs in people of all ages and is most dangerous for young children,especially infants.The introducti... Pertussis is an acute and highly contagious respiratory disease caused by Bordetella pertussis(B.pertussis),which occurs in people of all ages and is most dangerous for young children,especially infants.The introduction of whole-cell pertussis vaccines(wPVs)in the 1950s dramatically reduced the incidence of pertussis worldwide[1].However,over the past two decades,many studies have reported the resurgence of pertussis in different countries[2].Epidemiological surveillance in Hubei Province over the last 3 years revealed a clear increasing trend in the incidence of pertussis during the coronavirus disease 2019(COVID-19)epidemic. 展开更多
关键词 PERTUSSIS dangerous HUBEI
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A Hybrid and Lightweight Device-to-Server Authentication Technique for the Internet of Things
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作者 Shaha Al-Otaibi Rahim Khan +3 位作者 Hashim Ali Aftab Ahmed Khan Amir Saeed Jehad Ali 《Computers, Materials & Continua》 SCIE EI 2024年第3期3805-3823,共19页
The Internet of Things(IoT)is a smart networking infrastructure of physical devices,i.e.,things,that are embedded with sensors,actuators,software,and other technologies,to connect and share data with the respective se... The Internet of Things(IoT)is a smart networking infrastructure of physical devices,i.e.,things,that are embedded with sensors,actuators,software,and other technologies,to connect and share data with the respective server module.Although IoTs are cornerstones in different application domains,the device’s authenticity,i.e.,of server(s)and ordinary devices,is the most crucial issue and must be resolved on a priority basis.Therefore,various field-proven methodologies were presented to streamline the verification process of the communicating devices;however,location-aware authentication has not been reported as per our knowledge,which is a crucial metric,especially in scenarios where devices are mobile.This paper presents a lightweight and location-aware device-to-server authentication technique where the device’s membership with the nearest server is subjected to its location information along with other measures.Initially,Media Access Control(MAC)address and Advance Encryption Scheme(AES)along with a secret shared key,i.e.,λ_(i) of 128 bits,have been utilized by Trusted Authority(TA)to generate MaskIDs,which are used instead of the original ID,for every device,i.e.,server and member,and are shared in the offline phase.Secondly,TA shares a list of authentic devices,i.e.,server S_(j) and members C_(i),with every device in the IoT for the onward verification process,which is required to be executed before the initialization of the actual communication process.Additionally,every device should be located such that it lies within the coverage area of a server,and this location information is used in the authentication process.A thorough analytical analysis was carried out to check the susceptibility of the proposed and existing authentication approaches against well-known intruder attacks,i.e.,man-in-the-middle,masquerading,device,and server impersonations,etc.,especially in the IoT domain.Moreover,proposed authentication and existing state-of-the-art approaches have been simulated in the real environment of IoT to verify their performance,particularly in terms of various evaluation metrics,i.e.,processing,communication,and storage overheads.These results have verified the superiority of the proposed scheme against existing state-of-the-art approaches,preferably in terms of communication,storage,and processing costs. 展开更多
关键词 Internet of things AUtheNTICITY security location communication
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Quantifying the Impact of In-Cab Alerts on Truck Speed Reductions in Ohio
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作者 Jairaj Desai Jijo K. Mathew Darcy M. Bullock 《Journal of Transportation Technologies》 2024年第3期273-288,共16页
In-cab alerts warn commercial vehicle drivers of upcoming roadway incidents, slowdowns and work zone construction activities. This paper reports on a study evaluating the driver response to in-cab alerts in Ohio. Driv... In-cab alerts warn commercial vehicle drivers of upcoming roadway incidents, slowdowns and work zone construction activities. This paper reports on a study evaluating the driver response to in-cab alerts in Ohio. Driver response was evaluated by measuring the statistical trends of vehicle speeds after the in-cab alerts were received. Vehicle speeds pre and post in-cab alert were collected over a 47 day period in the fall of 2023 for trucks traveling on interstate roadways in Ohio. Results show that approximately 22% of drivers receiving Dangerous Slowdown alerts had reduced their speeds by at least 5 mph 30 seconds after receiving such an alert. Segmenting this analysis by speed found that of vehicles traveling at or above 70 mph at the time of alerting, 26% reduced speeds by at least 5 mph. These speed reductions suggest drivers taking actional measures after receiving alerts. Future studies will involve further analysis on the impact of the types of alerts shown, roadway characteristics and overall traffic conditions on truck speeds passing through work zones. 展开更多
关键词 In-Cab Alerts Connected Truck Data Driver Alerts dangerous Slowdowns
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Dynamic Location Method for Shallow Ocean Bottom Nodes Using the Levenberg-Marquart Algorithm
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作者 TONG Siyou LI Junjie +2 位作者 XU Xiugang FANG Yunfen WANG Zhongcheng 《Journal of Ocean University of China》 SCIE CAS CSCD 2024年第4期953-960,共8页
Ocean bottom node(OBN)data acquisition is the main development direction of marine seismic exploration;it is widely promoted,especially in shallow sea environments.However,the OBN receivers may move several times beca... Ocean bottom node(OBN)data acquisition is the main development direction of marine seismic exploration;it is widely promoted,especially in shallow sea environments.However,the OBN receivers may move several times because they are easily affected by tides,currents,and other factors in the shallow sea environment during long-term acquisition.If uncorrected,then the imaging quality of subsequent processing will be affected.The conventional secondary positioning does not consider the case of multiple movements of the receivers,and the accuracy of secondary positioning is insufficient.The first arrival wave of OBN seismic data in shallow ocean mainly comprises refracted waves.In this study,a nonlinear model is established in accordance with the propagation mechanism of a refracted wave and its relationship with the time interval curve to realize the accurate location of multiple receiver movements.In addition,the Levenberg-Marquart algorithm is used to reduce the influence of the first arrival pickup error and to automatically detect the receiver movements,identifying the accurate dynamic relocation of the receivers.The simulation and field data show that the proposed method can realize the dynamic location of multiple receiver movements,thereby improving the accuracy of seismic imaging and achieving high practical value. 展开更多
关键词 OBN dynamic location method Levenberg-Marquart algorithm seismic exploration of shallow sea
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Earthquake relocation using a 3D velocity model and implications on seismogenic faults in the Beijing-Tianjin-Hebei region
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作者 Jinxin Hou Yunpeng Zhang +1 位作者 Liwei Wang Zhirong Zhao 《Earthquake Research Advances》 CSCD 2024年第2期55-64,共10页
To enhance the understanding of the geometry and characteristics of seismogenic faults in the Beijing-Tianjin-Hebei region,we relocated 14805 out of 16063 earthquakes(113°E-120°E,36°N-43°N)that occ... To enhance the understanding of the geometry and characteristics of seismogenic faults in the Beijing-Tianjin-Hebei region,we relocated 14805 out of 16063 earthquakes(113°E-120°E,36°N-43°N)that occurred between January 2008 and December 2020 using the double-difference tomography method.Based on the spatial variation in seismicity after relocation,the Beijing-Tianjin-Hebei region can be divided into three seismic zones:Xingtai-Wen'an,Zhangbei-Ninghexi,and Tangshan.(1)The Xingtai-Wen'an Seismic Zone has a northeastsouthwest strike.The depth profile of earthquakes perpendicular to the strike reveals three northeast-striking,southeast-dipping,high-angle deep faults(>10 km depth),including one below the shallow(<10 km depth)listric,northwest-dipping Xinghe fault in the Xingtai region.Two additional deep faults in the Wen'an region are suggested to be associated with the 2006 M 5.1 Wen'an Earthquake and the 1967 M 6.3 Dacheng earthquake;(2)The Zhangbei-Ninghexi Seismic Zone is oriented north-northwest.Multiple northeast-striking faults(10-20 km depth),inferred from the earthquake-intensive zones,exist beneath the shallow(<10 km depth)Xiandian Fault,Xiaotangshan Fault,Huailai-Zhuolu Basin North Fault,Yangyuan Basin Fault and Yanggao Basin North Fault;(3)In the Tangshan Seismic Zone,earthquakes are mainly concentrated near the northeast-striking Tangshan-Guye Fault,Lulong Fault,and northwest-striking Luanxian-Laoting Fault.An inferred north-south-oriented blind fault is present to the north of the Tangshan-Guye Fault.The 1976 M 7.8 Tangshan earthquake occurred at the junction of a shallow northwest-dipping fault and a deep southeast-dipping fault.This study emphasizes that earthquakes in the region are primarily associated with deep blind faults.Some deep blind faults have different geometries compared to shallow faults,suggesting a complex fault system in the region.Overall,this research provides valuable insights into the seismogenic faults in the Beijing–Tianjin–Hebei region.Further studies and monitoring of these faults are essential for earthquake mitigation efforts in this region. 展开更多
关键词 BEIJING-TIANJIN-HEBEI Double difference tomography Earthquake location Seismogenic faults
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A Method to Obtain the Moving Speed of Uncooperative Target Based on Only Two Measurements
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作者 Tao Yu 《Advances in Aerospace Science and Technology》 2024年第1期1-9,共9页
The existing research results show that a fixed single station must conduct three consecutive frequency shift measurements and obtain the target’s moving speed by constructing two frequency difference equations. This... The existing research results show that a fixed single station must conduct three consecutive frequency shift measurements and obtain the target’s moving speed by constructing two frequency difference equations. This article proposes a new method that requires only two consecutive measurements. While using the azimuth measurement to obtain the angular difference between two radial distances, it also conducts two consecutive Doppler frequency shift measurements at the same target azimuth. On the basis of this measurement, a frequency difference equation is first constructed and solved jointly with the Doppler frequency shift equation. By eliminating the velocity variable and using the measured angular difference to obtain the target’s lead angle, the target’s velocity can be solved by using the Doppler frequency shift equation again. The new method avoids the condition that the target must move equidistantly, which not only provides an achievable method for engineering applications but also lays a good foundation for further exploring the use of steady-state signals to achieve passive positioning. 展开更多
关键词 Moving Speed Non-Cooperative Target Doppler Frequency Shift Frequency Difference Equation AZIMUTH Steady-State Signal Passive location
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Estimation of Lightning-Generated NO_(x) in the Mainland of China Based on Cloud-to-Ground Lightning Location Data 被引量:1
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作者 Qi LI Fengxia GUO +4 位作者 Xiaoyu JU Ze LIU Mingjun GAN Kun ZHANG Binbin CAI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第1期129-143,共15页
Lightning-generated nitrogen oxides(LNO_(x))have a major influence on the atmosphere and global climate change.Therefore,it is of great importance to obtain a more accurate estimation of LNO_(x).The aim of this study ... Lightning-generated nitrogen oxides(LNO_(x))have a major influence on the atmosphere and global climate change.Therefore,it is of great importance to obtain a more accurate estimation of LNO_(x).The aim of this study is to provide a reference for the accurate estimation of the total LNO_(x) in the mainland of China based on cloud-to-ground lightning(CG)location data from 2014 to 2018.The energy of each CG flash was based on the number of return strokes per CG flash,the peak current of each return stroke,and the assumed CG breakdown voltage.The energy of intracloud lightning(IC)was based on the estimated frequencies of IC and the assumed energy of each IC flash.Combining the energy of lightning and the number of nitric oxide(NO)molecules produced by unit energy(ρno),the total LNO_(x) production in the mainland of China was determined.The LNO_(x) in the mainland of China estimated in this study is in the range(0.157-0.321)×10^(9) kg per year[Tg(N)yr-1],which is on the high end of other scholars’works.Negative cloud-to-ground lightning(NCG)flashes produce the most moles of NO_(x),while positive cloud-to-ground lightning(PCG)flashes produce the least total moles of NO_(x).The breakdown voltage of PCG is greater than that of IC or NCG,while the latter has a greater output of LNO_(x). 展开更多
关键词 cloud-to-ground lightning location lightning peak current lightning breakdown voltage nitrogen oxide(NO_(x))
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On Fixed-Parameter Solvability of the Minimax Path Location Problem
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作者 Hao Lin Cheng He 《Communications on Applied Mathematics and Computation》 EI 2023年第4期1644-1654,共11页
The minimax path location problem is to find a path P in a graph G such that the maximum distance d_(G)(v,P)from every vertex v∈V(G)to the path P is minimized.It is a well-known NP-hard problem in network optimizatio... The minimax path location problem is to find a path P in a graph G such that the maximum distance d_(G)(v,P)from every vertex v∈V(G)to the path P is minimized.It is a well-known NP-hard problem in network optimization.This paper studies the fixed-parameter solvability,that is,for a given graph G and an integer k,to decide whether there exists a path P in G such that max v∈V(G)d_(G)(v,P)≤k.If the answer is affirmative,then graph G is called k-path-eccentric.We show that this decision problem is NP-complete even for k=1.On the other hand,we characterize the family of 1-path-eccentric graphs,including the traceable,interval,split,permutation graphs and others.Furthermore,some polynomially solvable special graphs are discussed. 展开更多
关键词 Discrete location Path location Fixed-parameter solvability Graph characterization Polynomial-time algorithm
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Overview of the identification of traffic accident-prone locations driven by big data 被引量:1
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作者 Chunjiao Dong Naixin Chang 《Digital Transportation and Safety》 2023年第1期67-76,共10页
Effective identification of traffic accident-prone points can reduce accident risks and eliminate safety hazards.This paper first systematically compares the research in Chinese and foreign literature,and proposes thr... Effective identification of traffic accident-prone points can reduce accident risks and eliminate safety hazards.This paper first systematically compares the research in Chinese and foreign literature,and proposes three types of identification indicators,namely absolute,relative and comprehensive,according to different reference standards.According to the evaluation indicators and modelling methods,the current status of research and problems in identification theory and methods are systematically summarised in terms of mathematical statistics,cluster analysis,machine learning and conflict technology.The study shows that the foreign literature focuses on the innovation of data and indicators and changes from accident point safety management to road network safety management,while the research in Chinese literature focuses on the integration of multiple identification methods and theoretical innovation.Driven by big data,the identification of traffic accident-prone points has been further developed at the meso-micro scale.Morphological image processing methods are widely used,combined with GIS platforms,to accurately mine the spatial attributes and correlations of accidents.Also,considering the spatial and temporal distribution of accidents,the identification results are also transformed from regions to specific road sections and points to achieve more accurate identification. 展开更多
关键词 Traffic safety Accident-prone locations Review Data mining MESOSCALE
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Host niche, genotype, and field location shape the diversity and composition of the soybean microbiome
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作者 YANG Hong-jun YE Wen-wu +6 位作者 YU Ze SHEN Wei-liang LI Su-zhen WANG Xing CHEN Jia-jia WANG Yuan-chao ZHENG Xiao-bo 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第8期2412-2425,共14页
Plant-associated microbes represent a key determinant of plant fitness through acquiring nutrients,promoting growth,and resisting to abiotic and biotic stresses.However,an extensive characterization of the bacterial a... Plant-associated microbes represent a key determinant of plant fitness through acquiring nutrients,promoting growth,and resisting to abiotic and biotic stresses.However,an extensive characterization of the bacterial and fungal microbiomes present in different plant compartments of soybean in field conditions has remained elusive.In this study,we investigated the effects of four niches(roots,stems,leaves,and pods),four genotypes(Andou 203,Hedou 12,Sanning 16,and Zhonghuang 13),and three field locations(Jining,Suzhou,and Xuzhou)on the diversity and composition of bacterial and fungal communities in soybean using 16S and internal transcribed spacer rRNA amplicon sequencing,respectively.The soybean microbiome significantly differed across organs.Host genotypes explained more variation in stem bacterial community composition and leaf fungal community composition.Field location significantly affected the composition of bacterial communities in all compartments and the effects were stronger in the root and stem than in the leaf and pod,whereas field location explained more variation in stem and leaf fungal community composition than in the root and pod.The relative abundances of potential soybean fungal pathogens also differed among host organs and genotypes,reflecting the niches of these microbes in the host and probably their compatibility to the host genotypes.Systematic profiling of the microbiome composition and diversity will aid the development of plant protection technologies to benefit soybean health. 展开更多
关键词 MICROBIOME SOYBEAN plant pathogen endophytes host niche GENOTYPE field location
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Seasonal variation of the shape and location of the Luzon cold eddy
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作者 Ruili Sun Peiliang Li +3 位作者 Yanzhen Gu Chaojie Zhou Cong Liu Lin Zhang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第5期14-24,共11页
Using observational data from multiple satellites,we studied seasonal variations of the shape and location of the Luzon cold eddy(LCE)northwest of Luzon Island.The shape and location of the LCE have obvious seasonal v... Using observational data from multiple satellites,we studied seasonal variations of the shape and location of the Luzon cold eddy(LCE)northwest of Luzon Island.The shape and location of the LCE have obvious seasonal variations.The LCE occurs,develops,and disappears from December to April of the next year.During this period,the shape of the LCE changed from a flat ellipse to a circular ellipse,and the change in shape can be reflected by the increase of the ellipticity of the LCE from 0.16 to 0.82.The latitude of center location of the LCE changes from 17.4°N to 19°N,and the change in latitude can reach 1.6°.Further study showed that seasonal variation of the northeast monsoon intensity leads to the change in the shape and location of the LCE.The seasonal variation of the LCE shape can significantly alter the spatial distribution of the thermal front and chlorophyll a northwest of the Luzon Island by geostrophic advection. 展开更多
关键词 Luzon cold eddy seasonal variation shape and location thermal front chlorophyll a concentration
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Effect of Specific Verbal Instructions on the Identification of Pain Location during a Passive Straight Leg Raise Test
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作者 Masae Ikeya Takumi Jiroumaru +2 位作者 Hitomi Bunki Noriyuki Kida Teruo Nomura 《Open Journal of Therapy and Rehabilitation》 2023年第2期45-53,共9页
Musculoskeletal pain is common. Because pain is subjective, objectively describing it is crucial. However, pain assessment may cause distress in patients;therefore, physical therapists (PTs) should conduct these tests... Musculoskeletal pain is common. Because pain is subjective, objectively describing it is crucial. However, pain assessment may cause distress in patients;therefore, physical therapists (PTs) should conduct these tests quickly and accurately. Simple and clear instructions are recommended for pain assessment. However, few studies have provided evidence to support this hypothesis. Correspondingly, this study aimed to confirm the effectiveness of specific verbal instructions for pain location during five consecutive Passive Straight Leg Raise (PSLR) tests. The 28 asymptomatic participants (age 27.4 ± 9.6 years) who provided informed consent received five consecutive PSLR tests: three without and two with specific verbal instructions to ascertain pain intensity, quality, and location. The participants drew pain locations on a body chart and described the pain intensity and quality after each test. All participants were interviewed regarding the differences they noted in the presence and absence of specific verbal instructions. Each pain location was classified into one of ten areas for statistical analysis. The proportion of participants who changed the pain location was compared between the tests using McNemar’s test, and the kappa coefficient was confirmed for consistency of pain location. There was a significant difference in the proportion of participants who changed their pain location between the second and third tests and from the third to the fourth test (McNemar’s test: p = 0.003). Kappa coefficients had low consistency (κ = 0.28) just after receiving the specific verbal instructions in the fourth test compared to the third test. Consistency improved in the fifth test (κ = 0.57);93% of the participants answered that the pain location had become clearer. This study revealed the effects of specific verbal instructions in identifying pain locations. This detailed information may help PTs provide appropriate treatment and contribute to reducing pain in clinical settings. 展开更多
关键词 Specific Verbal Instructions Pain location Pain Assessment Passive Straight Leg Raise Test
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A Computational Analysis of the Influence of Anastomosis Angle on Stenosis-Prone Locations during Radio-Cephalic Arteriovenous Fistula Maturation
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作者 Yang Yang Pascale Kulisa +3 位作者 Benyebka Bou-Saïd Mahmoud El Hajem Serge Simoens Nellie Della Schiava 《Journal of Biomedical Science and Engineering》 2023年第6期81-93,共13页
In dialysis treatment, the radio-cephalic arteriovenous fistula (RCAVF) is a commonly used fistula, yet its low maturation rate remains a challenge. To enhance surgical outcomes, the relationship between stenosis-pron... In dialysis treatment, the radio-cephalic arteriovenous fistula (RCAVF) is a commonly used fistula, yet its low maturation rate remains a challenge. To enhance surgical outcomes, the relationship between stenosis-prone locations and RCAVF anastomosis angle is studied during maturation by developing two sets of RCAVF models for early (non-mature) and mature RCAVFs at five anastomosis angles. The impact of hemodynamics and wall shear stress (WSS) is examined to determine optimal anastomotic angles. Results indicate that acute angles produce more physiological WSS distributions and fewer disturbed regions, with early stenosis-prone regions located near the anastomosis that shift to the bending venous segment during remodeling. A pilot study comparing clinical and numerical results is conducted for validation. 展开更多
关键词 Radio-Cephalic Arteriovenous Fistula (RCAVF) Anastomosis Angle MATURATION Wall Shear Stress Distribution Stenosis-Prone locations
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Chromosome Location of the Male-sterility and Yellow Seedling Gene in Line 1066A of Foxtail Millet 被引量:10
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作者 王润奇 高俊华 +3 位作者 毛丽萍 杜瑞恒 刁现民 孙敬三 《Acta Botanica Sinica》 CSCD 2002年第10期1209-1212,共4页
Using foxtail millet (Setaria italica (L.) Beauv.) male-sterile line 1066A as female parent and Yugu 1 primary trisomic series (1 - 7) and tetrasomics 8, 9 as male parents, chromosome location of gene for male-sterili... Using foxtail millet (Setaria italica (L.) Beauv.) male-sterile line 1066A as female parent and Yugu 1 primary trisomic series (1 - 7) and tetrasomics 8, 9 as male parents, chromosome location of gene for male-sterility and yellow seedling in line 1066A was studied by primary trisomic analysis. The plants of F-1 generation of trisomics 2 - 9 were obtained by crossing with a great many plants of 1066A. F-1 generation of trisomics was similar to their male parent in morphologic characters, the color of their seedling was green, and pollen was partially fertile. The segregation ratio of fertility to sterility is 3:1 in F-2 generation of trisomics 2, 3, 4, 5, 7, 8 and 9; and 14:1 only in F-2 generation of trisomic 6 (chi(0.05)(2) = 0.012). The segregation ratio of green seedling to yellow seedling is 12:1 only in F-2 generation of trisomic 7 (chi(0.05)(2) = 0.31), but in other cases, this ratio is 3:1. The results indicated that the male-sterility gene was located on chromosome 6, and the gene for yellow seedling was monogenic recessive and located on chromosome 7. The rate of trisomics transmission by pollen was tested, trisomics 8 and 9 were the highest in rates of trisomics transmission and followed by trisomics 6 and 4. 展开更多
关键词 Setaria italica MALE-STERILE yellow seedling primary trisomic analysis chromosome location
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The MW5.5 earthquake on August 6,2023,in Pingyuan,Shandong,China:A rupture on a buried fault 被引量:4
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作者 Zhe Zhang Lisheng Xu Lihua Fang 《Earthquake Science》 2024年第1期1-12,共12页
On August 6,2023,a magnitude MW5.5 earthquake struck Pingyuan County,Dezhou City,Shandong Province,China.This event was significant as no large earthquakes had been recorded in the region for over a century,and no act... On August 6,2023,a magnitude MW5.5 earthquake struck Pingyuan County,Dezhou City,Shandong Province,China.This event was significant as no large earthquakes had been recorded in the region for over a century,and no active fault had been previously identified.This study collects 1309 P-wave arrival times and 866 S-wave arrival times from 74 seismic stations less than 200 km to the epicenter to constrain the spatial distribution of the mainshock and its 125 early aftershocks by the double difference earthquake relocation method,and selects 864 P-waveforms from 288 stations located within 800 km of the epicenter to constrain the focal mechanism solution of the mainshock through centroid moment tensor inversion.The relocation and the inversion indicate,the Pingyuan MW5.5 earthquake was caused by a rupture on a buried fault,likely an extensive segment of the Gaotang fault.This buried fault exhibited a dip of approximately 75°to the northwest,with a strike of 222°,similar to the Gaotang fault.The rupture initiated at the depth of 18.6 km and propagated upward and northeastward.However,the ground surface was not broken.The total duration of the rupture was~6.0 s,releasing the scalar moment of 2.5895×1017 N·m,equivalent to MW5.54.The moment rate reached the maximum only 1.4 seconds after the rupture initiation,and the 90%scalar moment was released in the first 4.6 s.In the first 1.4 seconds of the rupture process,the rupture velocity was estimated to be 2.6 km/s,slower than the local S-wave velocity.As the rupture neared its end,the rupture velocity decreased significantly.This study provides valuable insights into the seismic characteristics of the Pingyuan MW5.5 earthquake,shedding light on the previously unidentified buried fault responsible for the seismic activity in the region.Understanding the behavior of such faults is crucial for assessing seismic hazards and enhancing earthquake preparedness in the future. 展开更多
关键词 Shandong Pingyuan MW5.5 earthquake double-difference earthquake location centroid moment tensor inversion buried fault
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Rose Oil Composition from the Flowers of Rosa rugosa Thunb. Growing in Different Locations of China 被引量:1
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作者 刘红燕 张永清 《Agricultural Science & Technology》 CAS 2012年第6期1260-1262,共3页
[Objective] This study aimed to analyze the main compositions in the rose oil of the rose flowers from different regions in China. [Method] The oils from rose flowers of Rosa rugosa Thunb. collected from six provinces... [Objective] This study aimed to analyze the main compositions in the rose oil of the rose flowers from different regions in China. [Method] The oils from rose flowers of Rosa rugosa Thunb. collected from six provinces in China were obtained by hydrodistillation and further analyzed by GC-MS. [Result] The content of rose oil ranged from 0.023% (v/w) to 0.056% (v/w). Forty-nine constituents included nine alcohols, seventeen aliphatic hydrocarbons, twelve carbonyls, three miscellaneous compound, two benzenes and six esters, of which eicosane (0.84% -17.81% ), heneicosane (1.07%-26.65%), 2-methyl-heptane (0.12%-9.14%), 4,5-dimethyl octane (0.17%-3.13%), 3-methyl-hexane (0.27%-11.74%), citronellol (0.51%-9.53%) and linalool (0.31%-4.01%) were the main constituents. [Conclusion] The study indicates that there is qualitative and quantitative difference in chemical composition of rose oil of rose flowers produced in different areas in China. The influence of production area should be carefully considered in order to maintain a consistent production of quality herb. 展开更多
关键词 Rose oil GC-MS Geographic locations
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Quantitative data about active tectonics and possible locations of strong earthquakes in the future in the northwestern Beijing 被引量:19
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作者 冉勇康 陈立春 徐锡伟 《地震学报》 CSCD 北大核心 2001年第5期502-513,共12页
Deterministic, probabilistic and composite-grading methods are used to get the possible locations of strong earth-quakes in the future in Norwest Beijing and its vicinity based on the quantitative data and their accur... Deterministic, probabilistic and composite-grading methods are used to get the possible locations of strong earth-quakes in the future in Norwest Beijing and its vicinity based on the quantitative data and their accuracy about active tectonics in the research area and by ordering, some questions in the results are also discussed. It shows that the most dangerous fault segments for strong earthquakes in the future include: segments B and A of the southern boundary fault of the Yangyuan basin, the southern boundary fault of the Xuanhua basin, the east segment of the southern Huaian fault and the east segment of the northern YanggaoTianzhen fault. The most dangerous area is YangyuanShenjing basin, the second one is TianzhenHuaianXuanhua basin and the third dangerous areas are WanquanZhangjiakou and northeast of Yuxian to southwest of Fanshan. 展开更多
关键词 北京 活动构造定量资料 综合方法 强震地点 确定性方法 概率方法
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Microearthquake reveals the lithospheric structure at midocean ridges and oceanic transform faults
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作者 Zhiteng YU Jiabiao LI Weiwei DING 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第3期697-700,共4页
Mid-ocean ridge and oceanic transforms are among the most prominent features on the seafloor surface and are crucial for understanding seafloor spreading and plate tectonic dynamics,but the deep structure of the ocean... Mid-ocean ridge and oceanic transforms are among the most prominent features on the seafloor surface and are crucial for understanding seafloor spreading and plate tectonic dynamics,but the deep structure of the oceanic lithosphere remains poorly understood.The large number of microearthquakes occurring along ridges and transforms provide valuable information for gaining an indepth view of the underlying detailed seismic structures,contributing to understanding geodynamic processes within the oceanic lithosphere.Previous studies have indicated that the maximum depth of microseismicity is controlled by the 600-℃isotherm.However,this perspective is being challenged due to increasing observations of deep earthquakes that far exceed this suggested isotherm along mid-ocean ridges and oceanic transform faults.Several mechanisms have been proposed to explain these deep events,and we suggest that local geodynamic processes(e.g.,magma supply,mylonite shear zone,longlived faults,hydrothermal vents,etc.)likely play a more important role than previously thought. 展开更多
关键词 microearthquake mid-ocean ridge oceanic transform fault oceanic lithosphere thermal structure earthquake location
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Efficient Ship:A Hybrid Deep Learning Framework for Ship Detection in the River
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作者 Huafeng Chen Junxing Xue +2 位作者 Hanyun Wen Yurong Hu Yudong Zhang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第1期301-320,共20页
Optical image-based ship detection can ensure the safety of ships and promote the orderly management of ships in offshore waters.Current deep learning researches on optical image-based ship detection mainly focus on i... Optical image-based ship detection can ensure the safety of ships and promote the orderly management of ships in offshore waters.Current deep learning researches on optical image-based ship detection mainly focus on improving one-stage detectors for real-time ship detection but sacrifices the accuracy of detection.To solve this problem,we present a hybrid ship detection framework which is named EfficientShip in this paper.The core parts of the EfficientShip are DLA-backboned object location(DBOL)and CascadeRCNN-guided object classification(CROC).The DBOL is responsible for finding potential ship objects,and the CROC is used to categorize the potential ship objects.We also design a pixel-spatial-level data augmentation(PSDA)to reduce the risk of detection model overfitting.We compare the proposed EfficientShip with state-of-the-art(SOTA)literature on a ship detection dataset called Seaships.Experiments show our ship detection framework achieves a result of 99.63%(mAP)at 45 fps,which is much better than 8 SOTA approaches on detection accuracy and can also meet the requirements of real-time application scenarios. 展开更多
关键词 Ship detection deep learning data augmentation object location object classification
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