检索结果-南通市图书馆

Characterization of Bacterial Communities in Aerosols over Northern Chinese Marginal Seas and the Northwestern Pacific Ocean in Autumn

在线全文

学校读者我要写书评

暂无评论

Journal of Ocean University of China 2023年第1期22卷 136-150页

作者： ZHANG bo ZHEN Yu mi Tiezhu QI Jianhua YUAN Gang Key Laboratory of Marine Environment and Ecology Ministry of EducationOcean University of ChinaQingdao 266100China Laboratory for Marine Ecology and Environmental Science Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China College of Environmental Science and Engineering Ocean University of ChinaQingdao 266100China

The characteristics of the bacterial community structure in aerosols of different particle sizes over northern Chinese marginal seas and the northwestern Pacific Ocean in autumn were analyzed using high-throughput sequencing and the quantitative real-time PCR method based on 16S rRNA *** with environmental factors and air mass sources,the bacterial abundance,community diversity,composition and structural characteristics in aerosols were studied,which might provide a scientific evaluation for a comprehensive understanding of the characteristics,long-distance transmission and ecological effects of aerosols from coastal waters to the distant ocean(northwestern Pacific Ocean).At the junction of the South Yellow Sea and the East China Sea,the bacterial abundance in the aerosols was substantially affected by transmission of continental air masses and was higher than those in other samples,and the bacterial abundance in coarse particle(>2.1μm)samples was significantly higher than that in fine particle(missions of continental air masses,and their bacterial abundance in coarse particle samples was significantly lower than that in fine particle *** differences in the richness and diversity of bacterial communities were observed among all samples(P0.05).Among the environmental factors examined,a significant negative correlation was observed between bacterial community richness and temperature(P<0.05),and the bacterial community diversity was significantly positively correlated with the concentration of K^(+)(P<0.05).Canonical correspondence analysis showed that temperature,NH_(4)^(+) concentration and SO_(4)^(2−) concentration exerted significant effects on bacterial community struc

关键词： bioaerosol marine environment community structure particle size

Characteristics of Nitric-Oxide Emissions from Traditional Flame and miLD Combustion Operating in a Laboratory-Scale Furnace

同方期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

Journal of Thermal Science 2020年第4期29卷 868-883页

作者： SHU Ziyun WANG Feifei DAI Chong SI Jicang WANG bo mi Jianchun Department of Energy and Resource Engineering College of EngineeringPeking UniversityBeijing 100871China China Ship Development and Design Center Wuhan 430074China School of Environmental Science and Engineering Huazhong University of Science and TechnologyWuhan 430074China

This study investigated the formation and emission characteristics of nitric oxide(NO) from flameless miLD(moderate or intensive low-oxygen dilution) combustion(miLDC) versus traditional visible-flame combustion(TC) in a 30-k W furnace. both combustion processes were experimentally operated successively in the same furnace, burning natural gas at a fixed rate of 19 k W and the equivalence ratio of 0.86. Numerical simulations of TC and miLDC were carried out to explain their distinction in the measured furnace temperature and exhaust NO emissions. Present measurements of the NO emission(XNO) versus a varying furnace wall temperature(Tw) have revealed, at the first time, that the relationship of XNO ~ Tw was exponential in both TC and miLDC. By analyzing the simulated results, the average temperature over the reaction zone was identified to be the common characteristic temperature for scaling NO emissions of both cases. Moreover, relative to TC, miLDC had a fairly uniform temperature distribution and low peak temperature, thus reducing the NO emission by over 90%. The thermal-NO formation was found to contribute more than 70%-80% to the total XNO from TC while the N2O-intermediate route dominated the NO emission from miLDC.

关键词： miLD(moderate or intensive low-oxygen dilution)combustion traditional combustion NO emission

Large-scale automatic block adjustment from satellite to indoor photogrammetry

在线全文

学校读者我要写书评

暂无评论

Geo-Spatial Information Science 2023年第2期26卷 160-174页

作者： Deren Li bo Yang mi Wang Taiping Wang Yunlong Gao Yingdong Pi State Key Laboratory of Information Engineering in Surveying Mapping and Remote SensingWuhan UniversityWuhanChina

Block Adjustment(BA)is a critical procedure in the geometric processing of satellite images,responsible for compensating and correcting the geometric positioning errors of the *** accuracy of the photogrammetric products,including Digital Orthophoto Map(DOM),Digital Elevation Model(DEM),Digital Line Graphic(DLG),and Digital Raster Graphic(DRG),directly depends on the accuracy of BA *** recent years,the rapid development of related technologies such as Artificial Intelligence(AI),Computer Vision(CV),Unmanned Aerial Vehicles(UAVs)and big data has greatly facilitated and transformed the classical BA in *** paper first reviews the current status of BA and then looks into the ***,this paper provides a brief review of the key technologies involved in BA,including image matching,the establishment of adjustment model,the determination of the parameters and the detection of gross ***,taking the intercross and fusion of current technologies such as AI,cloud computing and big data with photogrammetry into account,this paper explores the future trends of ***,four typical cases of large-scale adjustment are introduced,including large-scale BA without Ground Control Points(GCPs)for optical stereo satellite images,large-scale BA with laser altimetry data for optical stereo satellite images,large-scale BA for UAV oblique photogrammetry,and large-scale BA for indoor photogrammetry in caves with a large number of close-range images.

关键词： Block Adjustment(BA) large-scale image matching control points review

Multi-Scenario millimeter Wave Wireless Channel Measurements and Sparsity Analysis

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

China Communications 2022年第11期19卷 16-31页

作者： Hang mi bo Ai Ruisi He Xin Zhou Zhangfeng Ma mi Yang Zhangdui Zhong Ning Wang State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong UniversityBeijing 100044China Henan Joint International Research Laboratory of Intelligent Networking and Data Analysis Zhengzhou UniversityZhengzhou 450001China PengCheng Laboratory Shenzhen 518000China National Institute of Metrology of China Beijing 100029China School of Information Engineering Zhengzhou UniversityZhengzhou 450001China

Wireless channel characteristics have significant impacts on channel modeling,estimation,and communication *** the channel sparsity is an important characteristic of wireless *** the sparse nature of wireless channels can reduce the complexity of channel modeling and estimation,and improve system design and performance *** with the traditional sub6 GHz channel,millimeter wave(mmWave)channel has been considered to be more sparse in existing ***,most research only assume that the mmWave channel is sparse,without providing quantitative analysis and ***,this paper evaluates the sparsity of mmWave channels based on mmWave channel measurements.A vector network analyzer(VNA)-based mmWave channel sounder is developed to measure the channel at 28 GHz,and multi-scenario channel measurements are *** Gini index,Rician𝐾factor and rootmean-square(RMS)delay spread are used to measure channel ***,the key factors affecting mmWave channel sparsity are *** is found that antenna steering direction and scattering environment will affect the sparsity of mmWave *** addition,the impact of channel sparsity on channel eigenvalue and capacity is evaluated and analyzed.

关键词： channel sparsity channel measurement mmWave channel measures of sparsity

Multi-Frequency Channel Characterization for Massive miMO Communications in Lobby Environment

在线全文

学校读者我要写书评

暂无评论

China Communications 2019年第9期16卷 79-92页

作者： Jianzhi Li bo Ai Ruisi He mi Yang Zhangdui Zhong State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong University

In this paper,a massive multiple input multiple output(miMO)channel measurement campaign with two setups is conducted in an indoor lobby *** the first setup,two types of 256-element virtual uniform rectangular arrays(URAs),i.e.,the 4×64 virtual URA and the 64×4 virtual URA are *** carrier frequency is 11 GHz;in the second setup,measurements are performed at 4,6,11,13,15,18 GHz at two different user *** channel characterization is presented by investigating the typical channel parameters,including average power delay profile(APDP),K factor,root mean square(RMS)delay spread,and coherence ***,the channel characteristics in angular domain are investigated by applying the space-alternating generalized expectation-maximization(SAGE)*** extracted multipath components(MPCs)are preliminarily clustered by visual inspection,and related to the interacting objects(IOs)in physical *** structures at multiple frequency bands are *** spread of departure is estimated to evaluate the directional dispersion at the base station(BS)*** results in this paper can help to reveal the propagation mechanisms in massive miMO channels,and provide a foundation for the design and application of the practical massive miMO system.

关键词： 5G Massive miMO channelmeasurement virtual array SAGE K factor RMS delay spread coherence bandwidth scatterer localization direction spread

在线全文

学校读者我要写书评

暂无评论

基于新型组网的无人机巡检任务处理优化方案

无线电工程 2024年第7期54卷 1634-1642页

作者：解冬东迟猛程卫平冯传奋米波山东高速集团有限公司山东济南250098 山东高速信息集团有限公司山东济南250102 中移系统集成有限公司河北石家庄050024

考虑用户移动性,特别是在无人机巡检场景下,由于多接入边缘计算(Multi-access Edge Computing, MEC)节点服务范围小,大概率发生任务迁移。任务迁移将增加任务处理的时延和成本。为了降低任务迁移概率,提出了一种新的MEC组网架构——MEC ... 详细信息

考虑用户移动性,特别是在无人机巡检场景下,由于多接入边缘计算(Multi-access Edge Computing, MEC)节点服务范围小,大概率发生任务迁移。任务迁移将增加任务处理的时延和成本。为了降低任务迁移概率,提出了一种新的MEC组网架构——MEC POOL。在此基础上,构建了MEC POOL组网架构下的任务处理效益模型,将任务处理效益最优问题转换成受限条件下最优解问题。为了解决上述最优解问题,设计了一种基于任务处理效益最优的粒子群算法。实验结果表明,在发生任务迁移的场景下,MEC POOL组网方案相比MEC传统组网方案,任务处理效益和任务处理时延效益均可提升10%以上。对于多用户场景,平均任务处理效益提升8%以上,平均任务处理时延减少10%以上。

关键词：无人机巡检任务处理多接入边缘计算新型组网

Five-point Element Scheme of Finite Analytic Method for Unsteady Groundwater Flow

同方期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

工程科学（英文版） 2007年第1期5卷 101-105页

作者： Xiang bo~1, mi Xiao~2,Ji Changming~3, Luo Qingsong~4(1. State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan 430072 2. Dept. of Environmental Engineering, North China Institute of Water Conservancy and Hydroelectric Power, Zhengzhou 450008 3. North China Electric Power University, Beijing 102206 4. China Satellite Communications Corporation Human Resource Department, Beijing 100083) State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan University Wuhan 430072 Dept. of Environmental Engineering North China Institute of Water Conservancy and Hydroelectric Power Zhengzhou 450008 North China Electric Power University Beijing 102206 China Satellite Communications Corporation Human Resource Department Beijing 100083

In order to improve the finite analytic method’s adaptability for irregular unit, by using coordinates rotation technique this paper establishes a five-point element scheme of finite analytic method. It not only solves unsteady groundwater flow equation but also gives the boundary condition. This method can be used to calculate the three typical questions of groundwater. By compared with predecessor’s computed result, the result of this method is more satisfactory.

关键词： irregular region finite analytic method unsteady groundwater flow Laplace equation

Apigenin ameliorates diabetic neuropathy in rats by modulating the TLR4/MyD88 signaling pathway

在线全文

学校读者我要写书评

暂无评论

Asian Pacific Journal of Tropical Biomedicine 2023年第11期13卷 469-478,I0003,I0004,I0005,I0006,I0008页

作者： Yan-bo Yu mi-Zhen Qiu Da-Ying Zhang Department of Pain The First Affiliated Hospital of Nanchang UniversityNanchang 330006China

Objective:To determine the neuroprotective effects of apigenin against streptozotocin(STZ)-induced diabetic neuropathy(DN).Methods:To induce DN,Wistar rats(150-200 g)were administered with STZ(55 mg/kg,i.p.).Then they were randomly assigned to various groups,viz.,normal,diabetic control,insulin(10 IU/kg,s.c.),apigenin(5,10,and 20 mg/kg,p.o.),and insulin(10 IU/kg)plus apigenin(20 mg/kg,p.o.).Various behavioral,biochemical,and molecular markers[tumor necrosis factor-alpha(TNF-α),interleukin(IL)-1β,IL-6,Toll-like receptor 4(TLR4),myeloid differentiation primary response 88(MyD88),and nuclear factor erythroid 2-related factor 2(Nrf2)]were ***:Apigenin(10 and 20 mg/kg,p.o.)substantially reduced plasma glucose levels,lipid profile,aspartate transaminase,alanine transaminase,glycated hemoglobin,and neural advanced glycation end products in STZ-induced DN rats(Pbody weight,urine output,allodynia,hyperalgesia,and insulin levels were markedly improved(Pminished following apigenin therapy(P<0.05).Furthermore,apigenin markedly upregulated the Nrf2 mRNA level while downregulating the mRNA expressions of TNF-αand ILs and the protein expressions of TLR4 and MyD88(P<0.05).STZ-induced histological abnormalities in the sciatic nerve were also improved by apigenin ***:Apigenin exerts its neuroprotective effect by modulating the inflammatory and oxidative stress pathways via regulating the TLR4-MyD88 signaling pathway.

关键词： Apigenin Diabetic neuropathy MyD88 Nrf2 Proinflammatory cytokines TLR4

RNA Interference-mediated Silencing of Phytochelatin Synthase Gene Reduce Cadmium Accumulation in Rice Seeds

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Integrative Plant Biology 2007年第7期49卷 1032-1037页

作者： Jiang-Chuan Li Jiang-bo Guo Wen-Zhong Xu mi Ma Key Laboratory of Photosynthesis and Environmental Molecular Physiology Institute of Botany the Chinese Academy of Sciences Beijing 100093 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China

Phytochelatins （PCs） play an important role in heavy metal resistance and accumulation. To reduce the accumulation of cadmium （Cd） in rice seeds, the expression of phytochelatin synthase （PCS） gene OsPCS1 was suppressed by RNA interference （RNAi）. A hairpin construct of a PCS fragment was designed in the pRNAi-OsPCS1 under the control of ZMM1, a seed-specific promoter from maize. The construct was introduced into rice （japonica） through Agrobacterium tumefaciens. The RNAi rice plantlets were selected and cultivated in pots exposured to 10 mg/kg Cd. The transcriptional level of OsPCS1 declined in seeds of some RNAi rice compared to the wild type. As a result Cd accumulation was reduced by about half in the seeds of RNAi rice. As expected, no apparent difference of growth appeared between RNAi and wild-type plants. The results suggest that this new approach can be used to control heavy metal accumulation in crops.

关键词： accumulation cadmium phytochelatin synthase rice RNA interference.