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Derivative Spectroscopy and its Application at Detecting the Weak Emission/Absorption Lines
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作者 Lihuan Yu Jiangdan Li +4 位作者 Jinliang Wang Jiajia Li Jiao Li Qiang Xi Zhanwen Han 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第3期205-223,共19页
The development of spectroscopic survey telescopes like Large Sky Area Multi-Object Fiber Spectroscopic Telescope(LAMOST),Apache Point Observatory Galactic Evolution Experiment and Sloan Digital Sky Survey has opened ... The development of spectroscopic survey telescopes like Large Sky Area Multi-Object Fiber Spectroscopic Telescope(LAMOST),Apache Point Observatory Galactic Evolution Experiment and Sloan Digital Sky Survey has opened up unprecedented opportunities for stellar classification.Specific types of stars,such as early-type emission-line stars and those with stellar winds,can be distinguished by the profiles of their spectral lines.In this paper,we introduce a method based on derivative spectroscopy(DS)designed to detect signals within complex backgrounds and provide a preliminary estimation of curve profiles.This method exhibits a unique advantage in identifying weak signals and unusual spectral line profiles when compared to other popular line detection methods.We validated our approach using synthesis spectra,demonstrating that DS can detect emission signals three times fainter than Gaussian fitting.Furthermore,we applied our method to 579,680 co-added spectra from LAMOST Medium-Resolution Spectroscopic Survey,identifying 16,629 spectra with emission peaks around the Hαline from 10,963 stars.These spectra were classified into three distinct morphological groups,resulting in nine subclasses as follows.(1)Emission peak above the pseudo-continuum line(single peak,double peaks,emission peak situated within an absorption line,P Cygni profile,Inverse P Cygni profile);(2)Emission peak below the pseudo-continuum line(sharp emission peak,double absorption peaks,emission peak shifted to one side of the absorption line);(3)Emission peak between the pseudo-continuum line. 展开更多
关键词 LINE identification-line profiles-methods data analysis-techniques spectroscopic-techniques radial velocities
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Characterization of the infectivity of an Indonesian Zika virus strain in mammalian cell lines
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作者 Justus Thomas Obiajulu Sievers Anom Bowolaksono R.Tedjo Sasmono 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2024年第5期215-224,共10页
Objective:To characterize the infection patterns and growth characteristics of the Zika virus(ZIKV)strain JMB-185 from Indonesia in various mammalian cell lines.Methods:ZIKV was grown in human(A549,HEK293,HepG2,Huh7,J... Objective:To characterize the infection patterns and growth characteristics of the Zika virus(ZIKV)strain JMB-185 from Indonesia in various mammalian cell lines.Methods:ZIKV was grown in human(A549,HEK293,HepG2,Huh7,Jurkat,and THP-1)and non-human mammalian(RAW264.7,Vero,and Vero76)cell lines.Viral replication kinetics were measured using plaque assay,while intra-and extracellular viral RNA concentrations were assessed using RT-PCR.Flow cytometry was used to quantify the infected cells and cell viability was measured using an MTT assay.The ability of ZIKV to infect cell lines was visualized using a fluorescence immunostaining assay.Results:This ZIKV strain preferentially infected the lung,kidney,and liver cell lines A549,HEK293,Huh7,Vero,and Vero76,but not the immune cells Jurkat,RAW264.7,and THP-1.By contrast,the ZIKV showed no sign of infection in HepG2 cells,while maintaining viral titer over 3 days post-infection,with no infection recorded in immunostaining,no increase in viral RNA,and no indication of cell deterioration.Conclusions:The Indonesian ZIKV strain has a similar infection profile as other strains,except for its poor infectivity on HepG2 cells.Information on the growth characteristics of Indonesia ZIKV will help expand our understanding of the biology of ZIKV which will be useful for various applications including antiviral discovery. 展开更多
关键词 Zika virus Infectivity REPLICATION Cell lines In vitro
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GATA binding protein 2 mediated ankyrin repeat domain containing 26 high expression in myeloid-derived cell lines
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作者 Yang-Zhou Jiang Lan-Yue Hu +11 位作者 Mao-Shan Chen Xiao-Jie Wang Cheng-Ning Tan Pei-Pei Xue Teng Yu Xiao-Yan He Li-Xin Xiang Yan-Ni Xiao Xiao-Liang Li Qian Ran Zhong-Jun Li Li Chen 《World Journal of Stem Cells》 SCIE 2024年第5期538-550,共13页
BACKGROUND Thrombocytopenia 2,an autosomal dominant inherited disease characterized by moderate thrombocytopenia,predisposition to myeloid malignancies and normal platelet size and function,can be caused by 5’-untran... BACKGROUND Thrombocytopenia 2,an autosomal dominant inherited disease characterized by moderate thrombocytopenia,predisposition to myeloid malignancies and normal platelet size and function,can be caused by 5’-untranslated region(UTR)point mutations in ankyrin repeat domain containing 26(ANKRD26).Runt related transcription factor 1(RUNX1)and friend leukemia integration 1(FLI1)have been identified as negative regulators of ANKRD26.However,the positive regulators of ANKRD26 are still unknown.AIM To prove the positive regulatory effect of GATA binding protein 2(GATA2)on ANKRD26 transcription.METHODS Human induced pluripotent stem cells derived from bone marrow(hiPSC-BM)INTRODUCTION Ankyrin repeat domain containing protein 26(ANKRD26)acts as a regulator of adipogenesis and is involved in the regulation of feeding behavior[1-3].The ANKRD26 gene is located on chromosome 10 and shares regions of homology with the primate-specific gene family POTE.According to the Human Protein Atlas database,the ANKRD26 protein is localized to the Golgi apparatus and vesicles,and its expression can be detected in nearly all human tissues[4].Moreover,UniProt annotation revealed that ANKRD26 is localized in the centrosome and contains coiled-coil domains formed by spectrin helices and ankyrin repeats[5,6].The most common disease related to ANKRD26 is thrombocytopenia 2(THC2),which is a rare autosomal dominant inherited disease characterized by lifelong mild-to-moderate thrombocytopenia and mild bleeding[7-9].Caused by the variants in the 5’-untranslated region(UTR)of ANKRD26,THC2 is defined by a decrease in the number of platelets in circulating blood and results in increased bleeding and decreased clotting ability[8,10].Due to the point mutations that occur in the 5’-UTR of ANKRD26,its negative transcription factors(TFs),Runt related transcription factor 1(RUNX1)and friend leukemia integration 1(FLI1),lose their repression effect[11].The persistent expression of ANKRD26 increases the activity of the mitogen activated protein kinase and extracellular signal regulated kinase 1/2 signaling pathways,which are potentially involved in the regulation of thrombopoietin-dependent signaling and further impair proplatelet formation by megakaryocytes(MKs)[11].However,the positive regulators of ANKRD26,which might be associated with THC2 pathology,are still unknown. 展开更多
关键词 Ankyrin repeat domain containing 26 GATA binding protein 2 Thrombocytopenia 2 Transcriptional regulation Myeloid-derived cell lines
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Line ×Tester Analysis of Tropical High Land Maize (<i>Zea mays</i>L.) Inbred Lines Top Crossed with Three East African Maize Populations
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作者 Teshale Assefa Habtamu Zeleke +1 位作者 Thumasi Afriye Paul Otyama 《American Journal of Plant Sciences》 2017年第2期126-136,共11页
Maize breeding efforts to generate high yielding and adaptive cultivars have recently been given emphasis by national maize breeding program. In Ethiopia, the maize production system is mainly dominated by subsistence... Maize breeding efforts to generate high yielding and adaptive cultivars have recently been given emphasis by national maize breeding program. In Ethiopia, the maize production system is mainly dominated by subsistence farmers where their production is below average. The objectives of this study were to determine the combining ability between lines and testers, and to evaluate the performance of crosses (hybrids) and parents for grain yield and yield component traits. Twenty-seven inbred lines were generated by crossing nine female lines (L1-L9) and three male testers (T1-T3) using line × tester mating system at International Maize and Wheat Improvement Center (CIMMYT), East African high land maize improvement program. The inbred lines along with parents were evaluated in randomized complete block design with two replications at three locations (Ambo, Kulumsa and Haramaya). Significant differences were observed among genotypes for all ten traits considered. Eight crosses (L1 × T2, L1 × T3, L3 × T3, L8 × T1, L4 × T2, L9 × T1, L2 × T1, and L2 × T2) had higher yield performance compared to other crosses across environments. Significant mean square differences were found across locations for general combining ability (GCA) due to lines for all traits except for number of kernel rows per ear, whereas GCA due to testers were significant only for grain yield, ear length and 1000-seed weight. Significant mean square due to GCA × Loc (both for lines and testers) was found for days to maturity (38.71*), 1000-seed weight (4582.36**) and grain yield (2756777**), while significant SCA × Loc interaction was found for all traits except number of kernel rows per ear (1.07), ear length (0.79) and ear diameter (0.12), suggesting that the importance of additive and non-additive gene effects in controlling these characters. 展开更多
关键词 MAIZE LINE tester Combing Ability CROSSES
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Molecular cytogenetic analyses of two new wheat-rye 6RL translocation lines with resistance to wheat powdery mildew 被引量:1
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作者 Shanying Zhu Haonan Du +9 位作者 Fuyu Su Jin Wang Qingfeng Meng Tianlei Liu Rui Guo Zhaozhao Chen Huanhuan Li Wenxuan Liu Pengtao Ma Huagang He 《The Crop Journal》 SCIE CSCD 2023年第2期584-592,共9页
Rye(Secale cereale)is a valuable gene donor for wheat improvement,especially for its resistance to diseases.Developing rye-derived resistance sources is important for wheat breeding.In the present study,two wheat-rye ... Rye(Secale cereale)is a valuable gene donor for wheat improvement,especially for its resistance to diseases.Developing rye-derived resistance sources is important for wheat breeding.In the present study,two wheat-rye derivatives,designated JS016 and JS110,were produced by crossing common wheat cultivar Yangmai 23 with Pakistani rye accession W2A.Using sequential genomic in situ hybridization(GISH)and multicolor fluorescence in situ hybridization(mc-FISH),JS016 and JS110 were identified as a T6BS.6RL translocation line and a T6BS.6BL6RL translocation line,respectively.Ten newly 6RL chromosome arm-specific markers were developed and used to confirm the 6RL translocation.The wheat 55K single-nucleotide polymorphism(SNP)array further verified the molecular cytogenetic identification results above and clarified their breakpoints at 430.9 and 523.0 Mb of chromosome 6B in JS016 and JS110,respectively.Resistance spectrum and allelism test demonstrated that JS016 and JS110 possessed novel powdery mildew resistance gene(s)that was derived from the 6RL translocation but differed from Pm20.Moreover,JS016 and JS110 had better agronomic traits than the previously reported 6RL translocation line carrying Pm20.To efficiently transfer and detect the 6RL translocation from JS016 and JS110,one 6RL-specific Kompetitive allele specific PCR(KASP)marker was developed and validated in high throughput marker-assisted selection(MAS). 展开更多
关键词 Secale cereale Translocation line Wheat powdery mildew GISH/FISH KASP marker
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Minimization of Electric Power Losses on 132 kV and 220 kV Uganda Electricity Transmission Lines
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作者 Ounyesiga Living Stephen Ndubuisi Nnamchi +2 位作者 Kelechi John Ukagwu Abubakar Abdulkarim Zaid Oluwadurotimi Jagun 《Energy and Power Engineering》 CAS 2023年第2期127-150,共24页
The classical minimization of power losses in transmission lines is dominated by artificial intelligence techniques, which do not guarantee global optimum amidst local minima. Revolutionary and evolutionary techniques... The classical minimization of power losses in transmission lines is dominated by artificial intelligence techniques, which do not guarantee global optimum amidst local minima. Revolutionary and evolutionary techniques are encumbered with sophisticated transformations, which weaken the techniques. Power loss minimization is crucial to the efficient design and operation of power transmission lines. Minimization of losses is one way to meet steady grid supply, especially at peak demand. Thus, this paper has presented a gradient technique to obtain optimal variables and values from the power loss model, which efficiently minimizes power losses by modifying the traditional power loss model that combines Ohm and Corona losses. Optimality tests showed that the unmodified model does not support the minimization of power losses on transmission lines as the Hessian matrix portrayed the maximization of power losses. However, the modified model is consistent with the gradient method of optimization, which yielded optimum variables and values from the power loss model developed in this study. The unmodified (modified) models for Bujagali-Kawanda 220 kV and Masaka West-Mbarara North 132 kV transmission lines in Uganda showed maximum power losses of 0.406 (0.391) and 0.452 (0.446) kW/km/phase respectively. These results indicate that the modified model is superior to the unmodified model in minimizing power losses in the transmission lines and should be implemented for the efficient design and operation of power transmission lines within and outside Uganda for the same transmission voltages. 展开更多
关键词 MINIMIZATION Power Losses Transmission lines Corona and Ohms Losses Transmission Model
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Fertility,genome stability,and homozygosity in a diverse set of resynthesized rapeseed lines
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作者 Elizabeth Ihien Katche Antje Schierholt +2 位作者 Heiko C.Becker Jacqueline Batley Annaliese S.Mason 《The Crop Journal》 SCIE CSCD 2023年第2期468-477,共10页
Rapeseed(Brassica napus,AACC)was formed by hybridization between progenitor species Brassica rapa(AA)and Brassica oleracea(CC).As a result of a limited number of hybridization events between specific progenitor genoty... Rapeseed(Brassica napus,AACC)was formed by hybridization between progenitor species Brassica rapa(AA)and Brassica oleracea(CC).As a result of a limited number of hybridization events between specific progenitor genotypes and strong breeding selection for oil quality traits,rapeseed has limited genetic diversity.The production of resynthesized B.napus lines via interspecific hybridization of the diploid progenitor species B.rapa and B.oleracea is one possible way to increase genetic variation in rapeseed.However,most resynthesized lines produced so far have been reported to be meiotically unstable and infertile,in contrast to established B.napus cultivars.This hinders both maintenance and use of this germplasm in breeding programs.We characterized a large set of 140 resynthesized lines produced by crosses between B.rapa and B.oleracea,as well as between B.rapa and wild C genome species(B.incana,B.hilarionis,B.montana,B.Bourgeaui,B.villosa and B.cretica)for purity(homozygosity),fertility,and genome stability.Self-pollinated seed set,seeds per ten pods as well as percentage pollen viability were used to estimate fertility.SNP genotyping was performed using the Illumina Infinium Brassica 60K array for 116 genotypes,with at least three individuals per line.Most of the material which had been advanced through multiple generations was no longer pure,with heterozygosity detected corresponding to unknown parental contributions via outcrossing.Fertility and genome stability were both genotypedependent.Most lines had high numbers of copy number variants(CNVs),indicative of meiotic instability,and high numbers of CNVs were significantly associated with reduced fertility.Eight putatively stable resynthesized B.napus lines were observed.Further investigation of these lines may reveal the mechanisms underlying this effect.Our results suggest that selection of stable resynthesized lines for breeding purposes is possible. 展开更多
关键词 FERTILITY Genome stability Copy number variants SNP genotyping Resynthesized lines
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Multi-Equipment Detection Method for Distribution Lines Based on Improved YOLOx-s
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作者 Lei Hu Yuanwen Lu +2 位作者 Si Wang Wenbin Wang Yongmei Zhang 《Computers, Materials & Continua》 SCIE EI 2023年第12期2735-2749,共15页
The YOLOx-s network does not sufficiently meet the accuracy demand of equipment detection in the autonomous inspection of distribution lines by Unmanned Aerial Vehicle(UAV)due to the complex background of distribution... The YOLOx-s network does not sufficiently meet the accuracy demand of equipment detection in the autonomous inspection of distribution lines by Unmanned Aerial Vehicle(UAV)due to the complex background of distribution lines,variable morphology of equipment,and large differences in equipment sizes.Therefore,aiming at the difficult detection of power equipment in UAV inspection images,we propose a multi-equipment detection method for inspection of distribution lines based on the YOLOx-s.Based on the YOLOx-s network,we make the following improvements:1)The Receptive Field Block(RFB)module is added after the shallow feature layer of the backbone network to expand the receptive field of the network.2)The Coordinate Attention(CA)module is added to obtain the spatial direction information of the targets and improve the accuracy of target localization.3)After the first fusion of features in the Path Aggregation Network(PANet),the Adaptively Spatial Feature Fusion(ASFF)module is added to achieve efficient re-fusion of multi-scale deep and shallow feature maps by assigning adaptive weight parameters to features at different scales.4)The loss function Binary Cross Entropy(BCE)Loss in YOLOx-s is replaced by Focal Loss to alleviate the difficulty of network convergence caused by the imbalance between positive and negative samples of small-sized targets.The experiments take a private dataset consisting of four types of power equipment:Transformers,Isolators,Drop Fuses,and Lightning Arrestors.On average,the mean Average Precision(mAP)of the proposed method can reach 93.64%,an increase of 3.27%.The experimental results show that the proposed method can better identify multiple types of power equipment of different scales at the same time,which helps to improve the intelligence of UAV autonomous inspection in distribution lines. 展开更多
关键词 Distribution lines UAV autonomous inspection power equipment detection YOLOx-s
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Construction of EMS-Induced Peanut Mutant Libraries and Identification of Pod-Related Traits Mutant Lines
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作者 Hao Chen Faqian Xiong +9 位作者 Rilong Xu Xiangyu Chen Haifeng Zhong Yumei Zhang Xinlong Lan Hong Zhang Yuhua Chen Runfang Hu Guoqiang Lin Zhaoxiu Tang 《Phyton-International Journal of Experimental Botany》 SCIE 2023年第2期537-557,共21页
Peanut(Arachis hypogaea L.)is an oil and economic crop of vital importance,and peanut pod is the key organ influencing the yield and processing quality.Hence,the Pod-related traits(PRTs)are considered as important agr... Peanut(Arachis hypogaea L.)is an oil and economic crop of vital importance,and peanut pod is the key organ influencing the yield and processing quality.Hence,the Pod-related traits(PRTs)are considered as important agronomic traits in peanut breeding.To broaden the variability of PRTs in current peanut germplasms,three elite peanut cultivars were used to construct Ethyl methane sulfonate(EMS)-induced mutant libraries in this study.The optimal EMS treatment conditions for the three peanut varieties were determined.It was found that the median lethal dose(LD50)of EMS treatment varied greatly among different genotypes.Finally,the EMS-induced peanut mutant libraries were constructed and a total of 124 mutant lines for PRTs were identified and evaluated.Furthermore,“M-8070”,one of the mutant lines for pod constriction,was re-sequenced via high-throughput sequencing technology.The genome-wide variations between“M-8070”and its wild parent“Fuhua 8”(FH 8)were detected.2994 EMS-induced single nucleotide polymorphisms(SNPs)and 1188 insertion-deletions(InDels)between“M-8070”and its wild parent were identified.The predominant SNP mutation type was C/G to T/A transitions,while the predominant InDel mutation type was“1-bp”.We analyzed the distribution of identified mutations and annotated their functions.Most of the mutations(91.68%of the SNPs and 77.69%of the InDels)were located in the intergenic region.72 SNPs were identified in the exonic region,leading to 27 synonymous,43 nonsynonymous and 2 stop-gain variation for gene structure.13 Indels were identified in the exonic region,leading to 4 frame-shift,8 non-frame-shift and 1 stop-gain variations of genes.These mutations may lead to the phenotypic variation of“M-8070”.Our study provided valuable resources for peanut improvement and functional genomic research. 展开更多
关键词 PEANUT EMS-induced mutant line pod-related traits RE-SEQUENCING pod constriction
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Crossing Limit Cycles of Planar Piecewise Hamiltonian Systems with Linear Centers Separated by Two Parallel Straight Lines
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作者 Zhou Jin 《Journal of Applied Mathematics and Physics》 2023年第5期1429-1447,共19页
In this paper, we have studied several classes of planar piecewise Hamiltonian systems with three zones separated by two parallel straight lines. Firstly, we give the maximal number of limit cycles in these classes of... In this paper, we have studied several classes of planar piecewise Hamiltonian systems with three zones separated by two parallel straight lines. Firstly, we give the maximal number of limit cycles in these classes of systems with a center in two zones and without equilibrium points in the other zone (or with a center in one zone and without equilibrium points in the other zones). In addition, we also give examples to illustrate that it can reach the maximal number. 展开更多
关键词 Limit Cycles Planar Piecewise Hamiltonian Systems Straight lines CENTERS Equilibrium Points
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Saturated absorption spectrum of cesium micrometric-thin cell with suppressed crossover spectral lines
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作者 韩俊龙 王博闻 +5 位作者 郑俊鹤 陈书源 肖伟 吴腾 郭弘 彭翔 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第7期353-360,共8页
Micrometric-thin cells(MCs)with alkali vapor atoms have been valuable for research and applications of hyperfine Zeeman splitting and atomic magnetometers under strong magnetic fields.We theoretically and experimental... Micrometric-thin cells(MCs)with alkali vapor atoms have been valuable for research and applications of hyperfine Zeeman splitting and atomic magnetometers under strong magnetic fields.We theoretically and experimentally study the saturated absorption spectra using a 100-μm cesium MC,where the pump and probe beams are linearly polarized with mutually perpendicular polarizations,and the magnetic field is along the pump beam.Because of the distinctive thin chamber of the MC,crossover spectral lines in saturated absorption spectra are largely suppressed leading to clear splittings of hyperfine Zeeman transitions in experiments,and the effect of spatial magnetic field gradient is expected to be reduced.A calculation method is proposed to achieve good agreements between theoretical calculations and experimental results.This method successfully explains the suppression of crossover lines in MCs,as well as the effects of magnetic field direction,propagation and polarization directions of the pump/probe beam on saturated absorption spectrum.The saturated absorption spectrum with suppressed crossover lines is used for laser frequency stabilization,which may provide the potential value of MCs for high spatial resolution strong-field magnetometry with high sensitivity. 展开更多
关键词 micrometric-thin cells saturated absorption spectrum hyperfine Zeeman splitting crossover spectral lines laser frequency stabilization
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Data-Centric Approach to Digital Twin Modeling of Production Lines
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作者 丁永效 李纪奇 +2 位作者 刘国华 倪萍 吴金发 《Journal of Donghua University(English Edition)》 CAS 2023年第4期397-403,共7页
Digital twin(DT) is a virtual replica of a physical world that has become one of the most important ideas in the manufacturing industry’s digital revolution. DT modeling is a vital issue in building a DT of a product... Digital twin(DT) is a virtual replica of a physical world that has become one of the most important ideas in the manufacturing industry’s digital revolution. DT modeling is a vital issue in building a DT of a production line. In this paper, a method is proposed to address the difficulties of complicated production line business and data heterogeneity. The method focuses on essential data in the production line and creates conceptual and information models based on the ArtiFlow model and AutomationML(AML). Conceptual models are mainly used to describe and analyze the business activities of the production line, and information models describe real production lines in the form of XML files. The proposed modeling approach has been applied to a real-world clothing production line to demonstrate its feasibility and effectiveness. 展开更多
关键词 digital twin(DT) ArtiFlow production line AutomationML(AML)
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A Miniaturized Broadband Wilkinson Power Divider Using Micro-Strip Branch Lines
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作者 Taifu Zhou 《Journal of Computer and Communications》 2023年第12期102-108,共7页
A miniaturized broadband Wilkinson power divider is proposed. Micro-strip branch lines are introduced to replace multiple resistors used in multi-stage Wilkinson power dividers to increase the bandwidth of single-stag... A miniaturized broadband Wilkinson power divider is proposed. Micro-strip branch lines are introduced to replace multiple resistors used in multi-stage Wilkinson power dividers to increase the bandwidth of single-stage Wilkinson power dividers. To demonstrate its performance, an improved single-stage Wilkinson power divider with four micro-strip branch lines was designed. Simulated results show that the insert loss is better than 3.2 dB, the input return loss, output return loss, and isolation are better than 15 dB respectively, across a 76% bandwidth from 18 to 40 GHz. . 展开更多
关键词 BROADBAND Micro-Strip Branch lines Power Divider
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Analysis and Simulation of the Influence of Electromagnetic Fields on Living Beings near HV Power Lines Using the FDTD Method
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作者 Anthony Bassesuka Sandoka Nzao 《Open Journal of Applied Sciences》 2023年第12期2343-2359,共17页
Recent decades have seen rapid advances in the field of electrical engineering, such that our environment has become a sea of electrical and magnetic signals, raising questions about the possible effects of low-freque... Recent decades have seen rapid advances in the field of electrical engineering, such that our environment has become a sea of electrical and magnetic signals, raising questions about the possible effects of low-frequency electromagnetic fields on the environment and which are capable of modifying and destroying our ecosystem. Particular interest was given in this article due to a massive influx of population living near high voltage lines. The analysis and simulation of the influence of low frequency electromagnetic fields on living beings in the vicinity of high voltage sources 132 kV and 220 kV in urban areas in DR Congo is the subject of our research with a view to estimating the level of exposure of humans to low frequency electromagnetic fields. To carry out our research, we used the classic method of analyzing the field produced near a high voltage line based on Maxwell’s image theory, the Maxwell-Gauss theorem and Maxwell-Ampère theorem to model and quantify low-frequency electromagnetic fields in the vicinity of high-voltage lines. The 2D FDTD numerical formulation was developed from telegraphers’ equations and allowed us to obtain models of current and voltage induced by electromagnetic fields on living beings below and near HV lines. The different simulations carried out on the proposed models illustrate the effects of the electrical and geometric parameters of the pylons on the distribution of the electromagnetic field in the vicinity of the HV lines. The results obtained were compared to the safety limits recommended by the standards. 展开更多
关键词 Low Frequency Electromagnetic Field Modeling Field and Health Maxwell’s Equations FDTD Method Electromagnetic Compatibility High Voltage Line
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眩晕的经络相关性研究
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作者 刘婕 姜敏 冯兴中 《现代中西医结合杂志》 CAS 2024年第8期1077-1080,1145,共5页
目的观察眩晕患者的中医经络检测仪能量值的变化,探讨中医经络能量值与眩晕的相关性。方法选取2021年3月—2022年3月于北京世纪坛医院门诊及住院诊治的106例眩晕患者为研究组,以同期健康受试者117例为对照组,采用中医经络检测仪对2组受... 目的观察眩晕患者的中医经络检测仪能量值的变化,探讨中医经络能量值与眩晕的相关性。方法选取2021年3月—2022年3月于北京世纪坛医院门诊及住院诊治的106例眩晕患者为研究组,以同期健康受试者117例为对照组,采用中医经络检测仪对2组受试者十二正经原穴经络能量值进行测量和比较,采用Logistic回归分析法对经络能量值和眩晕相关性进行分析。结果2组受试者的性别、年龄及十二正经原穴中冲阳(胃经)、太白(脾经)、神门(心经)、腕骨(小肠经)、太溪(肾经)、大陵(心包经)、阳池(三焦经)、丘虚(胆经)、太冲(肝经)能量值比较差异均无统计学意义(P均>0.05),而太渊(肺经)、阳溪(大肠经)、束骨(膀胱经)能量值比较差异均有统计学意义(P均<0.05)。Logistic回归分析显示,膀胱经能量偏低为眩晕的独立影响因素(OR=0.957,95%CI:0.923~0.991,P=0.014)。结论眩晕患者膀胱经能量低(束骨),肺经(太渊)及大肠经(阳溪)能量亢进,其他经络能量变化无规律可言,提示该病症的发生可能与膀胱经能量值异常相关。 展开更多
关键词 眩晕 经络 中医经络检测仪
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2种硬度检测方法在压力管道检验中的有效性对比
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作者 李志峰 杨利军 宋利滨 《管道技术与设备》 CAS 2024年第2期34-37,共4页
采用便携式里氏硬度计和实时压痕分析仪对不同材质、不同壁厚的试样进行了硬度检测。通过对比验证方法研究了布氏硬度压痕法和里氏硬度试验方法在相同试验条件下得到的硬度值,同时将实时压痕分析仪所得的材料力学性能数值与试验数据进... 采用便携式里氏硬度计和实时压痕分析仪对不同材质、不同壁厚的试样进行了硬度检测。通过对比验证方法研究了布氏硬度压痕法和里氏硬度试验方法在相同试验条件下得到的硬度值,同时将实时压痕分析仪所得的材料力学性能数值与试验数据进行对比。结果表明:实时压痕分析仪测得的数据更准确,稳定性高,重复性好;可以现场无损且较准确获得材料力学性能。 展开更多
关键词 实时压痕分析仪 有效性 压力管道检验 里氏硬度计
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线卷积网络在二维线检测和三维线框重建中的应用
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作者 戴锡笠 龚海刚 刘明 《小型微型计算机系统》 CSCD 北大核心 2024年第1期192-198,共7页
本文提出了一个线卷积网络,可以从图像中检测线段.通过预测每条线段的中心位置、长度和角度,该网络能够以端到端的方式检测线段.此外,根据线中心检测的特点,本文设计了一维旋转卷积模块,并通过分析,证明其满足等变性质.在实现上,本文采... 本文提出了一个线卷积网络,可以从图像中检测线段.通过预测每条线段的中心位置、长度和角度,该网络能够以端到端的方式检测线段.此外,根据线中心检测的特点,本文设计了一维旋转卷积模块,并通过分析,证明其满足等变性质.在实现上,本文采用改进的数据增强和非极大值抑制方法,有效的提高了线检测的性能.通过大量消融实验以及对比实验,本文提出的线卷积网络相比于当前最优算法HAWP,在精度上高出3个百分点,达到了当前最优.最后,将该方法应用于单张图三维线框重建任务,从可视化结果上看,明显优于之前的方法. 展开更多
关键词 线检测 线卷积网络 等变性 三维线框重建
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立式去污测定仪校准方法研究
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作者 王鹏 陶笑昱 程葆明 《现代科学仪器》 2024年第1期28-31,共4页
立式去污测定仪是进行去污试验评价洗涤剂去污力的专用设备,主要应用于洗涤剂产品研发、测试及洗涤剂去污力和抗污渍再沉积能力试验等方面。针对目前国内市场尚无该设备的国家校准规范,该文从立式去污测定仪的物理性能出发,探讨该仪器... 立式去污测定仪是进行去污试验评价洗涤剂去污力的专用设备,主要应用于洗涤剂产品研发、测试及洗涤剂去污力和抗污渍再沉积能力试验等方面。针对目前国内市场尚无该设备的国家校准规范,该文从立式去污测定仪的物理性能出发,探讨该仪器的计量特性和校准方法,提出适用于该仪器的校准项目和技术指标。为验证该方法,以RHLQ-III型立式去污测定仪为实验对象,对温度偏差、温度波动度、温度均匀度、转速示值相对误差、定时相对误差5个项目进行校准试验。实验结果表明该校准方法准确可靠,有助于计量检定机构开展立式去污测定仪的校准工作。 展开更多
关键词 去污仪 计量 校准方法
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光温敏两系不育系‘稆S’的选育与应用
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作者 陈小玲 蒋云林 +3 位作者 钱子燕 王泓超 程祖锌 林荔辉 《亚热带农业研究》 2024年第1期9-14,共6页
[目的]选育优良的光温敏两系不育系,以提高其杂种后代的产量和品质。[方法]采用光温敏两系不育系‘RGD-7S’为母本与三系保持系‘中浙B’杂交,经5年9代的系谱法选育,育成不育性稳定、稻米品质优、异交特性好、株叶形态优良的光温敏两系... [目的]选育优良的光温敏两系不育系,以提高其杂种后代的产量和品质。[方法]采用光温敏两系不育系‘RGD-7S’为母本与三系保持系‘中浙B’杂交,经5年9代的系谱法选育,育成不育性稳定、稻米品质优、异交特性好、株叶形态优良的光温敏两系不育系‘稆S’,并分析了其主要特征特性及杂种优势。[结果]‘稆S’不育性稳定,育性转换临界温度<23℃,稳定不育期127 d左右。该不育系制种产量高,异交特性好,柱头外露率78.62%,其中双边外露率39.74%。采用‘稆S’配组的高产、优质两系杂交稻组合‘稆两优质美’先后通过了福建省和海南省农作物品种审定。[结论]光温敏两系不育系‘稆S’不育性稳定,育性转换临界温度低,稻米品质优,配合力强,应用前景广泛。 展开更多
关键词 水稻 光温敏两系不育系 优质 选育
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铝合金板冲压摩擦试验机开发与试验
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作者 李小强 张贺刚 +3 位作者 王烁 李高峰 孟庆阔 张永生 《北京航空航天大学学报》 EI CAS CSCD 北大核心 2024年第6期1898-1910,共13页
针对铝合金板冲压成形对摩擦测试的需求,确定考虑加热条件下铝合金板材冲压摩擦伺服压力摩擦测试平台的总体设计方案,开发适用于铝合金板材成形的小载荷高精度多功能摩擦试验机系统。该系统由运动组件、加热系统及控制系统组成。运动组... 针对铝合金板冲压成形对摩擦测试的需求,确定考虑加热条件下铝合金板材冲压摩擦伺服压力摩擦测试平台的总体设计方案,开发适用于铝合金板材成形的小载荷高精度多功能摩擦试验机系统。该系统由运动组件、加热系统及控制系统组成。运动组件实现上模具和夹头的运动支撑;加热系统实现模具与试件单独加热;在伺服控制模式下,结合外部力传感器和光栅尺,实现试件压力和模具间隙高精度高稳定性控制。实际应用检验该试验机对不同因素的区分度和重复性,并设计正交试验,探索不同因素对铝合金板材摩擦的影响。结果表明:试验机性能稳定,重复性好;影响摩擦系数因素的重要次序为:模具温度、压力、速度、润滑剂;温度越低,压力越大,速度越快,摩擦系数越小;同一种类型的润滑剂对摩擦系数的影响较小。随着压力的增大,摩擦系数减少的趋势越来越小,逐渐趋于平稳。 展开更多
关键词 摩擦试验机 铝合金板冲压 伺服控制 摩擦试验 摩擦学行为
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