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ASYMPTOTIC NORMALITY OF PARAMETERSESTIMATION IN EV MODEL WITH REPLICATEDOBSERVATIONS 被引量:3
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作者 张三国 陈希孺 《Acta Mathematica Scientia》 SCIE CSCD 2002年第1期107-114,共8页
This paper based on the essay [1], studies in case that replicated observations are available in some experimental points., the parameters estimation of one dimensional linear errors-in-variables (EV) models. Asymptot... This paper based on the essay [1], studies in case that replicated observations are available in some experimental points., the parameters estimation of one dimensional linear errors-in-variables (EV) models. Asymptotic normality is established. 展开更多
关键词 errors-in-variables model asymptotic normality replicated observations
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A New Primary Lazy Update Propagation Protocol for Replicated Databases
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作者 YANG Zhao-hong GONG Yun-zhan BI Xue-jun 《Wuhan University Journal of Natural Sciences》 EI CAS 2006年第1期263-268,共6页
This paper proposes a new primary lazy update protocol, PTCS (Primary Transaction Commit Schedule). In the PTCS protocol, a serializable primary transaction schedule is generated firstly and then the secondary trans... This paper proposes a new primary lazy update protocol, PTCS (Primary Transaction Commit Schedule). In the PTCS protocol, a serializable primary transaction schedule is generated firstly and then the secondary transactions are committed according to the serializable primary transaction schedule. PTCS protocol can guarantee serializability if the data copy graph contains no directed circles. It can also be ex tended to eliminate all requirements on the data copy graph. Compared to earlier works, PTCS protocol not only imposes a much weaker requirement on the data placement, but also avoids the deadlock caused by transaction waits and extra message overhead. The performance experiments show that the degradation of the performance caused by the replica man- agement of the PTCS protocol is tolerable. 展开更多
关键词 data replication global serializability data copy graph
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Convergence Rate of Empirical Bayes for Two-parameter Exponential Distribution with Replicated Data
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作者 Wang De-hui LI NAI-YI 《Communications in Mathematical Research》 CSCD 2010年第3期211-218,共8页
In this paper, empirical Bayes test for a parameter θ of two-parameter exponential distribution is investigated with replicated past data. Under some conditions, the asymptotically optimal property is obtained. It is... In this paper, empirical Bayes test for a parameter θ of two-parameter exponential distribution is investigated with replicated past data. Under some conditions, the asymptotically optimal property is obtained. It is indicated that the rate of convergence can be very close to O(N-2^-1) in this case that a parameter μ is known. 展开更多
关键词 replicated data empirical Bayes asymptotic optimality
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No replicated association of the c.-312A >G in<i>EDG</i>1 with marbling in Niigata population of Japanese Black beef cattle
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作者 Bin Tong Narumi Fuke +5 位作者 Yui Himizu Hiroyuki Katou Masato Hatano Takeshi Ohta Hiroyuki Kose Takahisa Yamada 《Open Journal of Animal Sciences》 2013年第4期269-272,共4页
Marbling, defined by the amount and the distribution of intramuscular fat and measured as beef marbling score (BMS), is an economically important trait of beef cattle in Japan. We recently reported that a single nucle... Marbling, defined by the amount and the distribution of intramuscular fat and measured as beef marbling score (BMS), is an economically important trait of beef cattle in Japan. We recently reported that a single nucleotide polymorphism (SNP), namely, c.-312A > G, in the endothelial differentiation sphingolipid G-proteincoupled receptor, 1 (EDG1) gene was associated with the BMS level in the Japanese Black beef cattle population of Oita prefecture, with the G allele being associated with a high level of the BMS. Thus, the c.-312A > G SNP seems to be a candidate marker for marker-assisted selection. In this study, we investigated whether this association could be replicated in the Japanese Black beef cattle population of Niigata prefecture and analyzed the effect of the SNP genotypes on the carcass traits other than the BMS. No significant differences in the BMS level were detected among the genotypes of the c.-312A > G SNP in the Niigata Japanese Black beef cattle population. The SNP genotype had no significant effects on the carcass weight, rib eye area and rib thickness of the cattle population. These findings suggested that the association of the c.-312A > G SNP with the BMS level in the Japanese Black beef cattle population was not replicated in the Niigata population, and revealed no effects of the SNP genotype on the beef productivity in the Niigata population. Thus, we concluded that the c.-312A > G SNP is not useful for effective marker-assisted selection to increase meat quality and, additionally, meat productivity in Japanese Black beef cattle of Niigata prefecture. 展开更多
关键词 ASSOCIATION EDG1 Japanese Black BREED MARBLING replication Study Single NUCLEOTIDE Polymorphism
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Replicated association of the single nucleotide polymorphism in PNLIP with marbling in Niigata population of Japanese Black beef cattle
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作者 Hideki Tanomura Youji Muramatsu +3 位作者 Takuji Yamamoto Takeshi Ohta Hiroyuki Kose Takahisa Yamada 《Open Journal of Animal Sciences》 2013年第2期89-92,共4页
Marbling is regarded as an economically important trait of beef cattle inJapan, and measured as a beef marbling score (BMS). Our previous study reported an association between a single nucleotide polymorphism (SNP), r... Marbling is regarded as an economically important trait of beef cattle inJapan, and measured as a beef marbling score (BMS). Our previous study reported an association between a single nucleotide polymorphism (SNP), rs4164 8172, in the pancreatic lipase (PNLIP) gene and the BMS level, using the Japanese Black beef cattle population of Oita prefecture. Further, we showed that the T allele at the rs41648172 SNP is associated with a high level of the BMS. Thus, we suggested that the rs41648172 SNP seems to be a candidate marker for marker-assisted selection. Our present study was designed to investigate whether this association could be replicated in other independent Japanese Black cattle population and analyze the effect of the SNP genotypes on the carcass traits other than the BMS. We detected the marginally significant effect of the genotypes of the rs41648172 SNP on the BMS level by using the Japanese Black beef cattle population of Niigata prefecture (P = 0.0919), and obtained the result of the T allele associated with an increase in the BMS level, consistent with our previous data. In addition, we showed no significant association of the SNP with the subcutaneous fat thickness, carcass weight, rib eye area, rib thickness and yield estimate in the Japanese Black beef cattle population ofNiigataprefecture. Thus, we concluded that the rs41648172 SNP was useful for effective marker-assisted selection to increase the BMS level in Japanese Black beef cattle, based on the replicated association of the rs41648172 SNP with the BMS level in the other independent Japanese Black beef cattle population and no effect of the SNP genotypes on the carcass traits other than BMS. 展开更多
关键词 ASSOCIATION PNLIP Japanese Black BREED MARBLING replicATION Study Single NUCLEOTIDE POLYMORPHISM
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A novel method for geometric quality assurance of rock joint replicas in direct shear testing-Part 2:Validation and mechanical replicability
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作者 J.Larsson F.Johansson +3 位作者 D.Mas Ivars E.Johnson M.Flansbjer N.W.Portal 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第9期2209-2223,共15页
Each rock joint is unique by nature which means that utilization of replicas in direct shear tests is required in experimental parameter studies.However,a method to acquire knowledge about the ability of the replicas ... Each rock joint is unique by nature which means that utilization of replicas in direct shear tests is required in experimental parameter studies.However,a method to acquire knowledge about the ability of the replicas to imitate the shear mechanical behavior of the rock joint and their dispersion in direct shear testing is lacking.In this study,a novel method is presented for geometric quality assurance of replicas.The aim is to facilitate generation of high-quality direct shear testing data as a prerequisite for reliable subsequent analyses of the results.In Part 1 of this study,two quality assurance parameters,smf and V_(Hp100),are derived and their usefulness for evaluation of geometric deviations,i.e.geometric reproducibility,is shown.In Part 2,the parameters are validated by showing a correlation between the parameters and the shear mechanical behavior,which qualifies the parameters for usage in the quality assurance method.Unique results from direct shear tests presenting comparisons between replicas and the rock joint show that replicas fulfilling proposed threshold values of σ_(mf)<0.06 mm and|V_(Hp100)|<0.2 mm have a narrow dispersion and imitate the shear mechanical behavior of the rock joint in all aspects apart from having a slightly lower peak shear strength.The wear in these replicas,which have similar morphology as the rock joint,is in the same areas as in the rock joint.The wear is slightly larger in the rock joint and therefore the discrepancy in peak shear strength derives from differences in material properties,possibly from differences in toughness.It is shown by application of the suggested method that the quality assured replicas manufactured following the process employed in this study phenomenologically capture the shear strength characteristics,which makes them useful in parameter studies. 展开更多
关键词 Three-dimensional(3D)scanning Contact area measurements Direct shear testing Geometric quality assurance Mechanical replicability replicas Rock joint
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An analysis of quantitative PCR reliability through replicates using the C_(t)method
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作者 Chris C.Stowers Frederick R.Haselton Erik M.Boczko 《Journal of Biomedical Science and Engineering》 2010年第5期459-469,共11页
There is considerable interest in quantitatively measuring nucleic acids from single cells to small populations. The most commonly employed laboratory method is the real-time polymerase chain reaction (PCR) analyzed w... There is considerable interest in quantitatively measuring nucleic acids from single cells to small populations. The most commonly employed laboratory method is the real-time polymerase chain reaction (PCR) analyzed with the crossing point or crossing threshold (Ct) method. Utilizing a multiwell plate reader we have performed hundreds of replicate reactions each at a set of initial conditions whose initial number of copies span a concentration range of ten orders of magnitude. The resultant Ct value distributions are analyzed with standard and novel statistical techniques to assess the variability/reliability of the PCR process. Our analysis supports the following conclusions. Given sufficient replicates, the mean and/or median Ct values are statistically distinguishable and can be rank ordered across ten orders of magnitude in initial template concentration. As expected, the variances in the Ct distributions grow as the number of initial copies declines to 1. We demonstrate that these variances are large enough to confound quantitative classi?cation of the initial condition at low template concentrations. The data indicate that a misclassi?cation transition is centered around 3000 initial copies of template DNA and that the transition region correlates with independent data on the thermal wear of the TAQ polymerase enzyme. We provide data that indicate that an alternative endpoint detection strategy based on the theory of well mixing and plate ?lling statistics is accurate below the mis- classi?cation transition where the real time method becomes unreliable. 展开更多
关键词 Misclassification Transition Single Molecule Counting Rank Ordering Running Title PCR replicates and Reliability
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The Crossing Number of Two Classes of Join Graphs
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作者 LU Shengxiang WANG Shu WANG Jing 《数学进展》 北大核心 2025年第5期983-991,共9页
Determining the crossing number of a given graph is NP-complete. The cycle of length m is denoted by Cm = v1v2…vmv1. G^((1))_(m) (m ≥ 5) is the graph obtained from Cm by adding two edges v1v3 and vlvl+2 (3 ≤ l ≤ m... Determining the crossing number of a given graph is NP-complete. The cycle of length m is denoted by Cm = v1v2…vmv1. G^((1))_(m) (m ≥ 5) is the graph obtained from Cm by adding two edges v1v3 and vlvl+2 (3 ≤ l ≤ m−2), G^((2))m (m ≥ 4) is the graph obtained from Cm by adding two edges v1v3 and v2v4. The famous Zarankiewicz’s conjecture on the crossing number of the complete bipartite graph Km,n states that cr(Km,n)=Z(m,n)=[m/2][m-1/2][n/2[n-1/2].Based on Zarankiewicz’s conjecture, a natural problem is to study the change in the crossingnumber of the graphs obtained from the complete bipartite graph by adding certain edge sets.If Zarankiewicz’s conjecture is true, this paper proves that cr(G^((1))_(m)+Kn)=Z(m,n)+2[n/2] and cr(G^((2))_(m)+Kn)=Z(m,n)+n. 展开更多
关键词 crossing number DRAWING join graph
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基于Fork/Join模式的模幂算法并行化实现
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作者 张翔 《计算机应用文摘》 2025年第20期244-246,249,共4页
公钥加密与数字签名算法普遍依赖于模幂运算,而大整数模幂运算的核心瓶颈在于高计算复杂度的乘法与幂运算.在现有研究基础上,文章系统分析了二元法、Karatsuba算法及快速傅里叶变换(FFT)在模幂运算中的应用特点,并针对其计算效率与资源... 公钥加密与数字签名算法普遍依赖于模幂运算,而大整数模幂运算的核心瓶颈在于高计算复杂度的乘法与幂运算.在现有研究基础上,文章系统分析了二元法、Karatsuba算法及快速傅里叶变换(FFT)在模幂运算中的应用特点,并针对其计算效率与资源消耗进行了相应优化.进一步地,基于Java语言环境,采用多线程Fork/Join框架实现改进算法,以提升并行计算性能与整体运算效率. 展开更多
关键词 模幂 Karatsuba FFT JAVA Fork/join
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Electrically assisted pressure joining of dissimilar copper C11000 and aluminum 6061-T6 alloys
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作者 Tu-Anh Bui-Thi Thanh Thuong Do +3 位作者 Van Cong Phan Sung-Tae Hong Yijae Kim Heung Nam Han 《Journal of Materials Science & Technology》 2025年第31期90-101,共12页
The effect of current density on electrically assisted solid-state bulk joining,so-called electrically assisted pressure joining(EAPJ),of copper(Cu)C11000 and aluminum(Al)6061-T6 alloys is investigated.During EAPJ,var... The effect of current density on electrically assisted solid-state bulk joining,so-called electrically assisted pressure joining(EAPJ),of copper(Cu)C11000 and aluminum(Al)6061-T6 alloys is investigated.During EAPJ,various combinations of electric current density and duration are applied to the cylindrical specimen assembly to reach a fixed peak temperature during continuous axial compressive plastic deformation.Then,an additional electric current is periodically applied to the specimen assembly without plastic deformation to keep the temperature elevated.Microstructural observation confirms that the defect-free joint of the selected material combination is fabricated without melting and solidification.The athermal effect of electric current on the diffusion enhancement can be accommodated by introducing the effective activation energy or the effective temperature.The microstructural analysis also demonstrates that the current density both increases the thickness of the intermetallic compound(IMC)layer at the joint interface and affects the microstructural evolution of joining materials.Finally,the mechanical properties of the joint are strongly affected by the electric current density.The present study provides insight into the effect of electric current density on the solid-state joining mechanism of EAPJ of dissimilar material combinations. 展开更多
关键词 Solid-state joining Electrically assisted pressure joining Copper C11000 Aluminum AA6061-T6 Electroplasticity Current density
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The evolutionarily diverged single-stranded DNA-binding proteins SSB1/SSB2 differentially affect the replication,recombination and mutation of organellar genomes in Arabidopsis thaliana
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作者 Weidong Zhu Jie Qian +6 位作者 Yingke Hou Luke R.Tembrock Liyun Nie Yi-Feng Hsu Yong Xiang Yi Zou Zhiqiang Wu 《Plant Diversity》 2025年第1期127-135,共9页
Single-stranded DNA-binding proteins(SSBs)play essential roles in the replication,recombination and repair processes of organellar DNA molecules.In Arabidopsis thaliana,SSBs are encoded by a small family of two genes(... Single-stranded DNA-binding proteins(SSBs)play essential roles in the replication,recombination and repair processes of organellar DNA molecules.In Arabidopsis thaliana,SSBs are encoded by a small family of two genes(SSB1 and SSB2).However,the functional divergence of these two SSB copies in plants remains largely unknown,and detailed studies regarding their roles in the replication and recombination of organellar genomes are still incomplete.In this study,phylogenetic,gene structure and protein motif analyses all suggested that SSB1 and SSB2 probably diverged during the early evolution of seed plants.Based on accurate long-read sequencing results,ssb1 and ssb2 mutants had decreased copy numbers for both mitochondrial DNA(mtDNA)and plastid DNA(ptDNA),accompanied by a slight increase in structural rearrangements mediated by intermediate-sized repeats in mt genome and small-scale variants in both genomes.Our findings provide an important foundation for further investigating the effects of DNA dosage in the regulation of mutation frequencies in plant organellar genomes. 展开更多
关键词 SSB Organellar genomes replicATION Recombination MUTATION
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Discrepant involvement of homologous repair and non-homologous end joining pathways in maize development and growth
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作者 Shuanghui Zhao Leiming Zheng +5 位作者 Minghui Zheng Menghan Li Shuyue Li Nan Wu Yan He Jinghan Liu 《The Crop Journal》 2025年第2期406-417,共12页
Chromosomal DNA double-strand breaks(DSBs)are often generated in the genome of all living organisms.To combat DNA damage,organisms have evolved several DSB repair mechanisms,with nonhomologous end-joining(NHEJ)and hom... Chromosomal DNA double-strand breaks(DSBs)are often generated in the genome of all living organisms.To combat DNA damage,organisms have evolved several DSB repair mechanisms,with nonhomologous end-joining(NHEJ)and homologous recombination(HR)being the two most prominent.Although two major pathways have been extensively studied in Arabidopsis,rice and other mammals,the exact functions and differences between the two DSB repair pathways in maize still remain less well understood.Here,we characterized mre11a and rad50,mutants of HR pathway patterns,which showed drastic degradation of the typically persistent embryo and endosperm during kernel development.Loss of MRE11 or RAD50 function led to chromosomal fragments and chromosomal bridges in anaphase.While we also reported that the NHEJ pathway patterns,KU70 and KU80 are associated with developmental growth and genome stability.ku70 and ku80 both displayed an obvious dwarf phenotype.Cytological analysis of the mutants revealed extensive chromosome fragmentation in metaphase and subsequent stages.Loss of KU70/80 function upregulated the expression of genes involved in cell cycle progression and nuclear division.These results provide insights into how NHEJ and HR are mechanistically executed during different plant developmental periods and highlight a competitive and complementary relationship between the NHEJ and HR pathways for DNA double-strand break repair in maize. 展开更多
关键词 Homologous recombination Non-homologous end joining Double-strand break MAIZE
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Features and mechanisms of long-lived Myotis somatic fibroblasts in response to DNA replication stress
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作者 Xiao-Yan Huang Xiu-Yun Liu +5 位作者 Wei Wang Gao-Jing Liu You-Long Zhu Xiao Wen Kai-Qin Li Bo Zhao 《Zoological Research》 2025年第3期709-721,共13页
The DNA replication stress(RS)response is crucial for maintaining cellular homeostasis and promoting physiological longevity.However,the mechanisms by which long-lived species,such as bats,regulate RS to maintain geno... The DNA replication stress(RS)response is crucial for maintaining cellular homeostasis and promoting physiological longevity.However,the mechanisms by which long-lived species,such as bats,regulate RS to maintain genomic stability remain unclear.Also,recent studies have uncovered noncanonical roles of ribosome-associated factors in maintaining genomic stability.In this study,somatic skin fibroblasts from the long-lived big-footed bat(Myotis pilosus)were examined,with results showing that bat cells exhibited enhanced RS tolerance compared to mouse cells.Comparative transcriptome analysis under RS conditions revealed pronounced species-specific transcriptional differences,including robust up-regulation of ribosome biogenesis genes in bat cells and a markedly reduced activation of the P53 signaling pathway.These features emphasize a distinct homeostatic strategy in bat cells.Nuclear fragile X mental retardation-interacting protein 1(Nufip1),a ribosome-associated factor highly expressed in bat fibroblasts,was identified as a potential integrator of ribosomal and P53 signaling via its association with ribosomal protein S27-like(Rps27l).These findings provide direct cellular and molecular evidence for a noncanonical RS response in bats,highlighting a deeper understanding of the biological characteristics and genomic maintenance mechanisms of long-lived species. 展开更多
关键词 Long-lived species Myotis pilosus DNA replication stress Ribosome biogenesis P53 signaling Nufip1 Rps27l
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Dynamic Multi-Objective Gannet Optimization(DMGO):An Adaptive Algorithm for Efficient Data Replication in Cloud Systems
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作者 P.William Ved Prakash Mishra +3 位作者 Osamah Ibrahim Khalaf Arvind Mukundan Yogeesh N Riya Karmakar 《Computers, Materials & Continua》 2025年第9期5133-5156,共24页
Cloud computing has become an essential technology for the management and processing of large datasets,offering scalability,high availability,and fault tolerance.However,optimizing data replication across multiple dat... Cloud computing has become an essential technology for the management and processing of large datasets,offering scalability,high availability,and fault tolerance.However,optimizing data replication across multiple data centers poses a significant challenge,especially when balancing opposing goals such as latency,storage costs,energy consumption,and network efficiency.This study introduces a novel Dynamic Optimization Algorithm called Dynamic Multi-Objective Gannet Optimization(DMGO),designed to enhance data replication efficiency in cloud environments.Unlike traditional static replication systems,DMGO adapts dynamically to variations in network conditions,system demand,and resource availability.The approach utilizes multi-objective optimization approaches to efficiently balance data access latency,storage efficiency,and operational costs.DMGO consistently evaluates data center performance and adjusts replication algorithms in real time to guarantee optimal system efficiency.Experimental evaluations conducted in a simulated cloud environment demonstrate that DMGO significantly outperforms conventional static algorithms,achieving faster data access,lower storage overhead,reduced energy consumption,and improved scalability.The proposed methodology offers a robust and adaptable solution for modern cloud systems,ensuring efficient resource consumption while maintaining high performance. 展开更多
关键词 Cloud computing data replication dynamic optimization multi-objective optimization gannet optimization algorithm adaptive algorithms resource efficiency SCALABILITY latency reduction energy-efficient computing
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CRTC3 restricts SARS-CoV-2 replication and is antagonized by CREB
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作者 Li Yang Xiao-Tao Zeng +8 位作者 Rong-Hua Luo Ying Tang Si-Xue Ren Xin-Yan Long Xiang-Hui Fu Wan-Jiang Zhang Hai-Yan Ren Yong-Tang Zheng Wei Cheng 《Virologica Sinica》 2025年第1期92-108,共17页
Virus-encoding RNA-dependent RNA polymerase(RdRp)is essential for genome replication and gene transcription of human coronaviruses(HCoVs),including severe acute respiratory syndrome coronavirus 2(SARS-CoV-2).We previo... Virus-encoding RNA-dependent RNA polymerase(RdRp)is essential for genome replication and gene transcription of human coronaviruses(HCoVs),including severe acute respiratory syndrome coronavirus 2(SARS-CoV-2).We previously identified the interaction between the catalytic subunit NSP12 of SARS-CoV-2 RdRp and the host protein CREB-regulated transcription coactivator 3(CRTC3),a member of the CRTC family that regulates cyclic AMP response element-binding protein(CREB)-mediated transcriptional activation.Currently,the implication of CRTC3 in the pathogenesis of HCoVs is poorly understood.Herein,we demonstrated that CRTC3 attenuates RdRp activity and SARS-CoV-2 genome replication,therefore reducing the production of progeny viruses.The interaction of CRTC3 with NSP12 contributes to its inhibitory effect on RdRp activity.Furthermore,we expanded the suppressive effects of two other CRTC family members(CRTC1 and CRTC2)on the RdRp activities of lethal HCoVs,including SARS-CoV-2 and Middle East respiratory syndrome coronavirus(MERS-CoV),along with the CREB antagonization.Overall,our research suggests that CRTCs restrict the replication of HCoVs and are antagonized by CREB,which not only provides new insights into the replication regulation of HCoVs,but also offers important information for the development of anti-HCoV interventions. 展开更多
关键词 Human coronaviruses(HCoVs) RNA-Dependent RNA polymerase (RdRp) CREB-regulated transcription coactivator 3(CRTC3) Virus replication Virus-host interaction Cyclic AMP response element-binding protein(CREB)
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Numerical Simulation Analysis of FSPR Joint Forming for Steel / Al Alloy Hybrid Body⁃in⁃White
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作者 Lijun Han Rui Wang Fuyang Liu 《Journal of Harbin Institute of Technology(New Series)》 2025年第3期46-53,共8页
The development and application of large Die⁃Casting Al Alloy(DCAA)parts and Thermo⁃Formed Steel Sheets(TFSS)in Body⁃in⁃White(BIW)have created higher demands for the joining technology of high⁃strength steel/Al dissim... The development and application of large Die⁃Casting Al Alloy(DCAA)parts and Thermo⁃Formed Steel Sheets(TFSS)in Body⁃in⁃White(BIW)have created higher demands for the joining technology of high⁃strength steel/Al dissimilar materials.As an emerging technology,Flush Self⁃Piercing Riveting(FSPR)is still in the experimental phase and undergoing small batch equipment verification.This paper focuses on the joining methods for DCAA and TFSS in BIW,investigating the joining mechanisms,technical features,and forming principles of FSPR for steel/Al dissimilar materials with two⁃layer or three⁃layer plate combinations.Considering the TL4225/C611/CR5 sheet combination as a subject,the forming mechanism of high⁃quality joints was studied,and a physical and mathematical model was established to depict the relationship between the filling amount of the arc⁃gap and die dimensions,as well as the extrusion amount.This model effectively illustrates the relationship between the filling amount of the flowing metal in the arc⁃gap and critical parameters,such as die dimensions and feeding amounts.By simplifying the process of selecting joining parameters,it significantly reduces both the time and experimental workload associated with parameter selection.This provides a technical foundation for the application of DAAA and TFSS parts in BIW,enabling the rapid choice of appropriate joining parameters to meet the requirements for obtaining high⁃quality joints.The model can be effectively utilized to investigate the relationships between key parameters,including arc⁃gap radius,plate thickness,rivet arc radius,nail head radius,groove width,and feeding amount,while keeping other parameters constant.This approach provides a theoretical foundation for the design of Friction Stir Processing(FSP)joints and aids in the selection of optimal parameters. 展开更多
关键词 flush self⁃piercing riveting(FSPR) joining die⁃casting Al alloy(DCAA) thermo⁃formed steel sheets(TFSS) two or three⁃layer plate
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谁更像“人”?模型类型与人格设定对大语言模型复刻传播学实验准确率的影响
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作者 曾秀芹 陈珂璐 《新闻与传播评论》 北大核心 2026年第1期25-39,共15页
以ChatGPT-4o、DeepSeek-R1、豆包-1.5、Kimi-K1.5四种主流大语言模型为对象,采用2(有vs.无大五人格设定)×4(模型类型)实验设计,构建虚拟被试资料以复刻新闻传播学实验。结果显示,各模型拟合表现存在差异:DeepSeek-R1在模拟真人平... 以ChatGPT-4o、DeepSeek-R1、豆包-1.5、Kimi-K1.5四种主流大语言模型为对象,采用2(有vs.无大五人格设定)×4(模型类型)实验设计,构建虚拟被试资料以复刻新闻传播学实验。结果显示,各模型拟合表现存在差异:DeepSeek-R1在模拟真人平均趋势与行为变异性方面最优;ChatGPT-4o的总体方差拟合偏差较大,但主效应、间接效应复刻的准确性与稳定性较为突出。人格设定的影响方面,无大五人格组描述性统计更贴近真人,而有大五人格组因果效应复刻更稳定,唯一完整复刻两个主效应的模型即来自该组。中介效应复刻成功率偏低,但人格设定可在一定程度上缓解模型输出的方向与效应偏离趋势。此外,研究基于ChatGPT-4o进一步发现,实验对象类型(真人组vs.无大五人格组vs.有部分大五人格组vs.有全部大五人格组)对主效应与中介机制部分产生显著调节作用,其中大五人格设定可一定程度抑制模型极端响应。研究实现多模型横向比较与人格设定控制下的复刻实验,验证了大五人格设定对提升模型模拟精度的积极作用,同时指出模型复刻复杂心理机制的局限性,推动传播学实验向“人机共演”的新范式转变,也拓展“媒介即延伸”在智能传播语境下的现实外延。 展开更多
关键词 大语言模型 大五人格 复刻研究 硅基被试
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排序合并Join算法的新结果 被引量:5
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作者 孙文隽 李建中 《软件学报》 EI CSCD 北大核心 1999年第3期264-269,共6页
Join操作是数据库中最昂贵和最常用的操作.排序合并Join算法是实现Join操作的重要算法,得到了普遍接受并广为应用.在重新研究了排序合并Join算法后发现,同时对两个Join关系进行外排序是不必要的,会带来很大的... Join操作是数据库中最昂贵和最常用的操作.排序合并Join算法是实现Join操作的重要算法,得到了普遍接受并广为应用.在重新研究了排序合并Join算法后发现,同时对两个Join关系进行外排序是不必要的,会带来很大的额外开销.针对这个问题,提出了一种基于单关系外排序的分治Join算法,并在该算法的基础上提出了基于单关系外排序的并行分治Join算法.理论和实验结果证明,基于单关系排序的分治Join算法高于排序合并Join算法.特别是在并行计算环境下,基于单关系排序的并行分治Join算法的效率远远高于排序合并Join算法的并行版本. 展开更多
关键词 join操作 排序合并 Joni算法 数据库系统
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调度Fork-Join任务图的贪心算法 被引量:6
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作者 杨斌 张建军 杨峰 《计算机工程与设计》 CSCD 北大核心 2008年第15期3864-3866,3894,共4页
任务调度算法的目标是把组成并行程序的一组任务分配到多个处理器以使得程序的完成时间最短,这是一个NP完全问题。虽然许多算法在任务满足某些条件时能产生最优调度,但大多都忽略了节省处理器个数和最小化程序总的完成时间等问题。Fork-... 任务调度算法的目标是把组成并行程序的一组任务分配到多个处理器以使得程序的完成时间最短,这是一个NP完全问题。虽然许多算法在任务满足某些条件时能产生最优调度,但大多都忽略了节省处理器个数和最小化程序总的完成时间等问题。Fork-Join结构是一种并行处理的基本结构。因此,专门针对Fork-Join任务图,提出了一个能产生最优调度的新的贪心调度算法,该算法具有高的加速比和总体效率,时间复杂度为2,其中,表示任务集中任务的个数。实验结果表明,相比其它算法,该算法具有较短的调度长度、较短的完成时间,使用的处理器数较少。 展开更多
关键词 最优调度算法 任务复制 Fork—join任务图 关键任务 加速比
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并行数据库上的并行CMD-Join算法 被引量:5
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作者 李建中 都薇 《软件学报》 EI CSCD 北大核心 1998年第4期256-262,共7页
并行数据库在多处理机之间的分布方法(简称数据分布方法)对并行数据操作算法的性能影响很大.如果在设计并行数据操作算法时充分利用数据分布方法的特点,可以得到十分有效的并行算法.本文研究如何充分利用数据分布方法的特点,设计... 并行数据库在多处理机之间的分布方法(简称数据分布方法)对并行数据操作算法的性能影响很大.如果在设计并行数据操作算法时充分利用数据分布方法的特点,可以得到十分有效的并行算法.本文研究如何充分利用数据分布方法的特点,设计并行数据操作算法的问题,提出了基于CMD多维数据分布方法的并行CMD-Join算法.理论分析和实验结果表明。 展开更多
关键词 并行数据库 并行join算法 CMD-join算法
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