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Analysis of mechanical strengths of extreme line casing joint considering geometric, material, and contact nonlinearities
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作者 Ji-Yun Zhang Chi Peng +4 位作者 Jian-Hong Fu Quan Cao Yu Su Jian-Yun Pang Zi-Qiang Yu 《Petroleum Science》 SCIE EI CAS CSCD 2024年第3期1992-2004,共13页
To address the challenges associated with difficult casing running,limited annular space,and poor cementing quality in the completion of ultra-deep wells,the extreme line casing offers an effective solution over conve... To address the challenges associated with difficult casing running,limited annular space,and poor cementing quality in the completion of ultra-deep wells,the extreme line casing offers an effective solution over conventional casings.However,due to its smaller size,the joint strength of extreme line casing is reduced,which may cause failure when running in the hole.To address this issue,this study focuses on the CST-ZTΦ139.7 mm×7.72 mm extreme line casing and employs the elastic-plastic mechanics to establish a comprehensive analysis of the casing joint,taking into account the influence of geometric and material nonlinearities.A finite element model is developed to analyze the forces and deformations of the extreme line casing joint under axial tension and external collapse load.The model investigates the stress distribution of each thread tooth subjected to various tensile forces and external pressures.Additionally,the tensile strength and crushing strength of the extreme line casing joint are determined through both analytical and experimental approaches.The findings reveal that,under axial tensile load,the bearing surface of each thread tooth experiences uneven stress,with relatively high equivalent stress at the root of each thread tooth.The end thread teeth are valuable spots for failure.It is observed that the critical fracture axial load of thread decreases linearly with the increase of thread tooth sequence.Under external pressure,the circumferential stress is highest at the small end of the external thread,leading to yield deformation.The tensile strength of the joint obtained from the finite element model exhibits a relative error of less than 7%compared to the analytical and experimental values,proving the reliability of the finite element model.The tensile strength of the joint is 3091.9 k N.Moreover,in terms of anti-collapse capability,the joints demonstrate higher resistance to collapse compared to the casing body,which is consistent with the test results where the pipe body experiences collapse and failure while the joints remain intact during the experiment.The failure load of the casing body under external collapse pressure is 87.4 MPa.The present study provides a basic understanding of the mechanical strengths of extreme line casing joint. 展开更多
关键词 Extreme line casing Elastic-plastic mechanics Finite element analysis Tensile strength Collapse strength
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Automated deep learning system for power line inspection image analysis and processing: architecture and design issues 被引量:1
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作者 Daoxing Li Xiaohui Wang +1 位作者 Jie Zhang Zhixiang Ji 《Global Energy Interconnection》 EI CSCD 2023年第5期614-633,共20页
The continuous growth in the scale of unmanned aerial vehicle (UAV) applications in transmission line inspection has resulted in a corresponding increase in the demand for UAV inspection image processing. Owing to its... The continuous growth in the scale of unmanned aerial vehicle (UAV) applications in transmission line inspection has resulted in a corresponding increase in the demand for UAV inspection image processing. Owing to its excellent performance in computer vision, deep learning has been applied to UAV inspection image processing tasks such as power line identification and insulator defect detection. Despite their excellent performance, electric power UAV inspection image processing models based on deep learning face several problems such as a small application scope, the need for constant retraining and optimization, and high R&D monetary and time costs due to the black-box and scene data-driven characteristics of deep learning. In this study, an automated deep learning system for electric power UAV inspection image analysis and processing is proposed as a solution to the aforementioned problems. This system design is based on the three critical design principles of generalizability, extensibility, and automation. Pre-trained models, fine-tuning (downstream task adaptation), and automated machine learning, which are closely related to these design principles, are reviewed. In addition, an automated deep learning system architecture for electric power UAV inspection image analysis and processing is presented. A prototype system was constructed and experiments were conducted on the two electric power UAV inspection image analysis and processing tasks of insulator self-detonation and bird nest recognition. The models constructed using the prototype system achieved 91.36% and 86.13% mAP for insulator self-detonation and bird nest recognition, respectively. This demonstrates that the system design concept is reasonable and the system architecture feasible . 展开更多
关键词 Transmission line inspection Deep learning Automated machine learning Image analysis and processing
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Stylistic Analysis on English On-line Chat
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作者 别尽秋 闻扬波 《海外英语》 2013年第6X期224-225,227,共3页
Based on the fact that on-line chat has become the most developing language form in the information age, this article point out the stylistic features of on-line English chat. Though in written language form, such lan... Based on the fact that on-line chat has become the most developing language form in the information age, this article point out the stylistic features of on-line English chat. Though in written language form, such language is spoken language in nature, thus it is worthwhile to analyze this special phaenomenon in lexical and grammatical level. 展开更多
关键词 on-line ENGLISH STYLISTIC analysis LEXICAL grammat
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DEVELOPMENT AND APPLICATIONS OF AN ON-LINE THERMAL NEUTRON PROMPT-GAMMA ELEMENT ANALYSIS SYSTEM 被引量:1
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作者 刘雨人 卢允信 +5 位作者 谢亚丽 王永海 杜幼玲 谈进 孟伯年 R.S.Seymour 《Nuclear Science and Techniques》 SCIE CAS CSCD 1991年第2期71-78,共8页
This paper introduces the principles, instrumentation, implementation, and industrial applications of an on- line thermal neutron prompt- gamma element analysis system (using a 252Cf neutron source, Am- Be neutron sou... This paper introduces the principles, instrumentation, implementation, and industrial applications of an on- line thermal neutron prompt- gamma element analysis system (using a 252Cf neutron source, Am- Be neutron source, or neutron generator). The energy resolution of the system at the H prompt- gamma full- energy photopeak (2.22325 MeV) is 3.6 keV. The concentration measurement error of A12O3, Fe2O3, CaO and SiO2 is ±0.3%,±0.1%.±0.4% and ±0.4%, respectively.The system has been tested on- site at both the Shandong and the Zhengzhou Aluminum Works. Our preliminary on- site measurements confirm that the stability, reliability, measurement range, and accuracy of the system can meet the requirements of the aluminum production process. Facilitation of this measurement at aluminum plants is expected to reduce plant costs by over 3 million dollars annually through reduced energy consumption, more rapid qualification of pulps being mixed during the production process, and in reduced labor costs. 展开更多
关键词 Prompt-gamma NEUTRON activation analysis on- line Aluminum PULP
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Mechanics Analysis of Overhead Transmission Lines Based On-line Monitoring
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作者 Lili Dai Yongli Zhu Zehui Liang 《Open Journal of Applied Sciences》 2013年第2期1-4,共4页
At present, the on-line monitoring is widely applied to the power line monitoring. In this paper, a new mechanical calculation model is established according to the on-line monitoring. And this model is based on the p... At present, the on-line monitoring is widely applied to the power line monitoring. In this paper, a new mechanical calculation model is established according to the on-line monitoring. And this model is based on the parameters that tension sensors and angle sensors on suspended points detect, and combines with the parameters of the wire itself, and also considers the deflection angel of wires due to wind. In this model, mechanics parameters of wires are turned into the new coordinate plane after deflection angel of wires due to wind, or windage yaw plane. A statics tension balance equation is built in the vertical direction of the new windage yaw plane. According to the theoretical analysis and algorithm, we verify the accuracy of this newly developed mechanical calculation model. 展开更多
关键词 OVERHEAD Transmission line on-line Monitoring Mechanical analysis Tension ANGLE ICING Windage Yaw
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Genetic Relation Analysis on Ramie[Boehmeria nivea(L.)Gaud.]Inbred Lines by SRAP Markers 被引量:15
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作者 LIU Li-jun PENG Ding-xiang WANG Bo 《Agricultural Sciences in China》 CAS CSCD 2008年第8期944-949,共6页
The objective of this article is to reveal the variations of ramie inbred lines in DNA level and discuss their molecular background to provide a theoretical basis for ramie cross breeding. In the present study, the ge... The objective of this article is to reveal the variations of ramie inbred lines in DNA level and discuss their molecular background to provide a theoretical basis for ramie cross breeding. In the present study, the genetic relationships among 33 inbred line accessions and two wild types that originated from China and Brazil were estimated using sequence-related amplified polymorphism (SRAP) markers. The results showed that 33 out of 81 primer combinations turned out to be polymorphic and 332 polymorphism bands were obtained. On the basis of the appearance of the markers, the genetic relationships were analyzed using unweighted pair-group method of arithmetic average cluster analysis (UPGMA), and the genetic Jaccard similarity coefficients were calculated. The inbred-lines originating from China and Brazil formed a cluster suggesting a possibility that the Brazilian cultivars could have developed from cultivars introduced from China. Within ramie inbred-lines, the groupings also indicated that the greatest genetic relationship among cultivars was correlated to the region of origin of cultivars. The results provided the evidence that SRAP was an efficient approach, suitable for taxonomic analysis of ramie inbred lines, To the authors' knowledge, this is the first application of SRAP marker on the systematics of ramie inbred lines. 展开更多
关键词 relatives of ramie inbred lines SRAP taxonomic analysis UPGMA
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Molecular analysis and anticancer properties of two identified isolates,Fusarium solani and Emericella nidulans isolated from Wady El-Natron soil in Egypt against Caco-2(ATCC) cell line 被引量:3
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作者 Hala F Mohamed 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2012年第11期863-869,共7页
Objective:To characterize,identify and investigate the anticancer properties of two new soil fungal isolates,Emericella nidulansand Fusarium solani isolated from Wady El-Natron in Egypt against colon cancer Caco-2(ATC... Objective:To characterize,identify and investigate the anticancer properties of two new soil fungal isolates,Emericella nidulansand Fusarium solani isolated from Wady El-Natron in Egypt against colon cancer Caco-2(ATCCj cell line.Methods:Soil sample was cultured and two strains were chosen for morphological and phenotypical characterization.Partial sequences of the 18s rRNA gene and the internal transcribed spacer region ITS of the two isolates were amplified by PCR.Phylogenetic tree construction and analysis of the resulted multiple sequences from the two fugal isolates were also carried out.In vitro anticancer activity of the two strains was done against colon Caco-2 cancer cell line.Reverse transcription — PCR was carried out to detect level of expression of p53 in Caco-2 cell line.Results:HF.I displayed morphological and genotypic characteristics most similar to that of Fusarium solani while HF.2 was most similar to Emericella nidulans with high similarity of 99%and 97%respectively.The multiple sequence alignment of the two fungal isolates showed that,the maximum identical conserved domains in the 18s rRNA genes were identified with the nucleotide regions of Slst to 399th base pairs,88th to 525th base pairs respectively.While those in the ITS genes were identified with the nucleotide regions of 88th to 463rd and Slst to 274th.The two isolates showed IC<sup><</sup>sub>50</sub> value with(6.24±5.21) and(9.84±0.36) μ g/mL) concentrations respectively at 28h.Reverse transcription- PCR indicated that these cells showed high level of expression for p53 mRNA.Conclusions:The morphology and molecular analysis identified HF.1 and HF.2 to be Fusarium solani and Emericella nidulans;new isolates of anticancer producing fungi from Wady El-Natroon city in Egypt.Treatment with the two isolates caused P53 expression in Caco-2 cell line.These two isolates can be used as an anticancer agents. 展开更多
关键词 Fungi Colon cancer CACO-2 Phylogenetic tree ANTICANCER property Multiple sequence analysis ANTICANCER agent Cell line
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Analysis on Genomic Structure Changes and Diversity of Introgression Lines in Dongxiang Wild Rice(Oryza rufipogon Griff.)
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作者 邓晓娟 罗向东 +4 位作者 谢建坤 万勇 胡标林 曹娟芳 戴亮芳 《Agricultural Science & Technology》 CAS 2012年第1期93-97,共5页
[Objective] The aim of the study was to make research on genomic struc- ture variation and variety analysis of Dongxiang wild rice. [Method] Introgression groups of BC1F6 were based on donor of Oryza rufipogon Griff. ... [Objective] The aim of the study was to make research on genomic struc- ture variation and variety analysis of Dongxiang wild rice. [Method] Introgression groups of BC1F6 were based on donor of Oryza rufipogon Griff. and receptor of O. sativa sp. indica Kate. Strains of 239 in the group were analyzed on Polymor- phism with the help of 25 couples of SSR primers distributed in 12 pairs of chromo- somes. [Result] Gene fragments of O. rufipogon Griff. were found penetrated in the 25 microsatellite sites and most of the groups kept the parents of Xieqinzao B or DNA sequence of O. rufipogon Griff. The average rate of recurrent homozygous bands was 78.13% in the ILs, but the highest was 94.98% (amplified by primer RM131) and the lowest was 60.25% (RM171). The average rate of donor homozy- gous bands was 13.37%, but the highest was 32.64% (RM171) and the lowest was 2.93% (RM1095). There were numerous heterozygous sites in the population and the average heterozygosis rate was 5.62%, while the highest was 10.04%(RM401). Moreover, we found some parental fragments were lost and some novel fragments were not detected in either parent in BC1F6 population. The average rate of lost bands was 2.88%, while the highest was 13.39% (RM311) and the lowest was 0 (RM401). The average rate of new bands was 1%. The average of Nei's gene di- versity (He) and Shannon's Information index (I) were 0.276 and 0.457 respectively in high generation of introgression lines. [Conclusion] The study demonstrated that distant hybridization led to extensive genetic and epigenetic variations in high gener- ation of introgression lines, which expanded the base of genetic variation and laid an important foundation for rice improvement and germplasm innovation. 展开更多
关键词 Oryza rufipogon Griff. Introgression lines SSR analysis Genomic structure changes Genetic variation
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Protein profile of human hepatocarcinoma cell line SMMC-7721:Identification and functional analysis 被引量:8
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作者 Yi Feng Zhong-Min Tian Ming-Xi Wan Zhao-Bin Zheng 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第18期2608-2614,共7页
AIM: TO investigate the protein profile of human hepatocarcinoma cell line SMMC-7721, to analyze the specific functions of abundant expressed proteins in the processes of hepatocarcinoma genesis, growth and metastasi... AIM: TO investigate the protein profile of human hepatocarcinoma cell line SMMC-7721, to analyze the specific functions of abundant expressed proteins in the processes of hepatocarcinoma genesis, growth and metastasis, to identify the hepatocarcinoma-specific biomarkers for the early prediction in diagnosis, and to explore the new drug targets for liver cancer therapy. METHODS: Total proteins from human hepatocarcinoma cell line SMMC-7721 were separated by two-dimensional electrophoresis (2DE). The silver-stained gel was analyzed by 2DE software Image Master 2D Elite. Interesting protein spots were identified by peptide mass fingerprinting based on matrix-assisted laser desorption/ ionization time-of-flight mass spectrometry (MALDI-TOF-MS) and database searching. RESULTS: We obtained protein profile of human hepatocarcinoma cell line SMMC-7721. Among the twenty-one successfully identified proteins, mitofilin, endoplasmic reticulum protein ERp29, ubiquinol-cytochrome C reductase complex core protein I, peroxisomal enoyl CoA hydratase, peroxiredoxin-4 and probable 3-oxoacid CoA transferase 1 precursor were the six novel proteins identified in human hepatocarcinoma cells or tissues. Specific functions of the identified heat-shock proteins were analyzed in detail, and the results suggested that these proteins might promote tumorigenesis via inhibiting cell death induced by several cancer-related stresses or via inhibiting apoptosis at multiple points in the apoptotic signal pathway. Other identified chaperones and cancer-related proteins were also analyzed.CONCLUSION: Based on the protein profile of SMMC-7721 cells, functional analysis suggests that the identified chaperones and cancer-related proteins have their own pathways to contribute to the tumorigenesis, tumor growth and metastasis of liver cancer. Furthermore, proteomic analysis is indicated to be feasible in the cancer study. 展开更多
关键词 Human hepatocarcinoma cell line SMMC-7721 Protein identification Functional analysis Heat-shockprotein Tumorigenesis
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Near Crack Line Elastic-Plastic Analysis for an Infinite Plate Loaded by a Pair of Point Shear Forces 被引量:5
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作者 周小平 王建华 黄煜镔 《Journal of Shanghai Jiaotong university(Science)》 EI 2003年第2期115-117,共3页
The near crack line analysis method was used to investigate a crack loaded by a pair of point shear forces in an infinite plate in an elastic-perfectly plastic solid. The analytical solution was obtained, that is the ... The near crack line analysis method was used to investigate a crack loaded by a pair of point shear forces in an infinite plate in an elastic-perfectly plastic solid. The analytical solution was obtained, that is the elastic-plastic fields near crack line and law that the length of the plastic zone along the crack line is varied with external loads. The results are sufficiently precise near the crack line and are not confined by small scale yielding conditions. 展开更多
关键词 near crack line elastic-plastic analysis a pair of point shear forces
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Analysis of field coupling to transmission lines with random rotation over the ground 被引量:1
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作者 谢海燕 李勇 +1 位作者 乔海亮 王建国 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第6期171-176,共6页
In this paper we analyze plane wave coupling to transmission lines rotating randomly over an infinite and perfectly conducting ground and present an efficient method to calculate average voltage. Under the assumption ... In this paper we analyze plane wave coupling to transmission lines rotating randomly over an infinite and perfectly conducting ground and present an efficient method to calculate average voltage. Under the assumption of small rotation quantity, the factors affecting the induced voltage and their effects are analyzed and then an efficient method to calculate the average voltage is presented when the distribution of the random rotation angles is uniform in [-π, π]. The results show that voltage variation is mainly due to the change of the source term. The effects of the source term increase linearly with the magnitude of the incident wave, change periodically with the rotation angle, and are larger in the high frequency range than in the low frequency range. The results show that the average voltages obtained by the proposed method agree well with those via the Monte Carlo method and the proposed method is much more efficient. The results also imply that the effect of random rotation is more important than that of random translation. 展开更多
关键词 electromagnetic interference induced voltage RANDOMNESS statistical analysis transmission line
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Sensitivity of Sample for Simulation-Based Reliability Analysis Methods 被引量:2
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作者 Xiukai Yuan Jian Gu Shaolong Liu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2021年第1期331-357,共27页
In structural reliability analysis,simulation methods are widely used.The statistical characteristics of failure probability estimate of these methods have been well investigated.In this study,the sensitivities of the... In structural reliability analysis,simulation methods are widely used.The statistical characteristics of failure probability estimate of these methods have been well investigated.In this study,the sensitivities of the failure probability estimate and its statistical characteristics with regard to sample,called‘contribution indexes’,are proposed to measure the contribution of sample.The contribution indexes in four widely simulation methods,i.e.,Monte Carlo simulation(MCS),importance sampling(IS),line sampling(LS)and subset simulation(SS)are derived and analyzed.The proposed contribution indexes of sample can provide valuable information understanding the methods deeply,and enlighten potential improvement of methods.It is found that the main differences between these investigated methods lie in the contribution indexes of the safety samples,which are the main factors to the efficiency of the methods.Moreover,numerical examples are used to validate these findings. 展开更多
关键词 Reliability analysis Monte Carlo simulation importance sampling line sampling subset simulation
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NEAR CRACK LINE ELASTIC-PLASTIC ANALYSIS FOR A CRACK LOADED BY ANTIPLANE POINT FORCES 被引量:1
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作者 吴承平 王成 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1996年第12期1121-1126,共6页
In this paper, the improved near crack line analysis method proposed in Refs. [1]and [2] is used to investigate a mode Ⅲ crack loaded by antiplane point forces in aninfinite plate in an elastic-perfectly plastic sol... In this paper, the improved near crack line analysis method proposed in Refs. [1]and [2] is used to investigate a mode Ⅲ crack loaded by antiplane point forces in aninfinite plate in an elastic-perfectly plastic solid. The solutions of this paper aresufficiently precise near the crack line region because. the assumptions of the smallscale yielding theory have not been used and no other assumptions have been taken. 展开更多
关键词 mode Ⅲcrack near crack line analysis ELASTIC-PLASTIC antiplane point forces
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Comprehensive Evaluation of New Self-cultivated Sugarcane Lines by Grey Relational Analysis 被引量:1
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作者 Wenqing MA Qiang GUO +3 位作者 Chizhang WEI Hengrui LI Chong PENG Zhenhua LIANG 《Asian Agricultural Research》 2014年第9期85-88,共4页
The grey relational analysis( GRA) was used to evaluate the 10 sugarcane lines by 13 main agronomic characters. The result showed that the grey correlation degree of self-cultivated lines GNY08- 320(0. 7502),GNY08- 33... The grey relational analysis( GRA) was used to evaluate the 10 sugarcane lines by 13 main agronomic characters. The result showed that the grey correlation degree of self-cultivated lines GNY08- 320(0. 7502),GNY08- 336(0. 7409),GNY08- 186(0. 7369),and GNY08- 225(0. 7277) were higher than ROC22(CK),so the 4 lines can be further tested,and the others were worse than CK that should be further observed or eliminated. 展开更多
关键词 SUGARCANE GREY RELATIONAL analysis lineS Comprehen
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Strain anisotropy models for refined diffraction line profile analysis in cubic metals 被引量:1
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作者 Xiang DAI Fu-lin JIANG +4 位作者 Jin LIU Luo-yi WU Ding-fa FU Jie TENG Hui ZHANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2020年第8期2090-2106,共17页
The present work examined the anisotropy magnitudes obtained from different elastic models of cubic metals(Cu,5383 Al alloy,FCC austenite steel and BCC steel)to explore the origin of strain anisotropy.The results show... The present work examined the anisotropy magnitudes obtained from different elastic models of cubic metals(Cu,5383 Al alloy,FCC austenite steel and BCC steel)to explore the origin of strain anisotropy.The results showed that stable intersections were observed from the modeled and experimental plots of the reciprocal elastic modulus(1/Ehkl)and orientation parameter(Γ).The effectiveness of quasi elasto-plastic model based method in correcting strain anisotropy was further verified in cold-worked specimens.For the important input parameters in dislocation model based diffraction line profile analysis methods,the average diffraction contrast factors(■)of dislocations were observed to depend on elastic constants.Interesting intersections were found from linear dependence of■onΓ.The conventional input■values indicated distinct dependencies on given elastic constants in diffraction line profile analysis.Accordingly,a refined approach was proposed by adopting the optimized intersections as input values,by which more reliable results could be obtained in practical applications. 展开更多
关键词 metallic materials line profile analysis strain anisotropy dislocations
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Cracking analysis of fracture mechanics by the finite element method of lines(FEMOL) 被引量:2
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作者 Shaowei Hu Brian Moran 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2005年第5期495-502,共8页
The Finite Element Method of Lines (FEMOL) is a semi-analytic approach and takes a position between FEM and analytic methods. First, FEMOL in Fracture Mechanics is presented in detail. Then, the method is applied to... The Finite Element Method of Lines (FEMOL) is a semi-analytic approach and takes a position between FEM and analytic methods. First, FEMOL in Fracture Mechanics is presented in detail. Then, the method is applied to a set of examples such as edge-crack plate, the central-crack plate, the plate with cracks emanating from a hole under tensile or under combination loads of tensile and bending. Their dimensionless stress distribution, the stress intensify factor (SIF) and crack opening displacement (COD) are obtained, and comparison with known solutions by other methods are reported. It is found that a good accuracy is achieved by FEMOL. The method is successfully modified to remarkably increase the accuracy and reduce convergence difficulties. So it is a very useful and new tool in studying fracture mechanics problems. 展开更多
关键词 The finite element method of lines (FEMOL) .Cracking analysis . Application
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Correlation Analysis on Male Sterile Lines Characters in Rapeseed(Brassica napus L.)
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作者 黄泽素 Laosuwan Paisan +4 位作者 Machikowa Thitiporn 陈泽辉 代文东 唐容 李德珍 《Agricultural Science & Technology》 CAS 2010年第9期183-187,共5页
[Objective] This study was conducted to evaluate the associations of many characters of male sterile lines in Brassica napus L.[Method]10 recessive genetic male sterile(RGMS)lines were used as parents to cross in a ... [Objective] This study was conducted to evaluate the associations of many characters of male sterile lines in Brassica napus L.[Method]10 recessive genetic male sterile(RGMS)lines were used as parents to cross in a half diallel cross method to produce 45 single cross hybrids.These 45 crosses and their 10 parents were evaluated at Guiyang during 2007-2008.[Result]The positive correlations of seed yield with plant height,pods per plant,days to flowering and days to maturity were significant.Their respective correlation coefficients(r)were 0.644,0.583,0.281 and 0.341.Highly significant and negative correlation was observed between seeds per pod and seed size(-0.533).Direct path coefficients were observed for pods per plant(0.556 2),seeds per pod(0.407 4),1 000-seed weight(0.481 3),and plant height(0.401 7)to seed yield.[Conclusion]Pods per plant,seeds per pod,1 000-seed weight and plant height were positive correlated with seed yield and showed high direct contributions to yield.Other characters including branches per plant,days to flowering,days to maturity and oil content had low contributions to seed yield. 展开更多
关键词 Brassica napus L. Male sterile line Correlation analysis CHARACTERS
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AN APPLICATION OF TOPOLOGICAL ANALYSIS TO STUDYING THE THREE-DIMENSIONAL FLOW IN CASCADES;PART I—TOPOLOGICAL RULES FOR SKIN-FRICTION LINES AND SECTION STREAMLINES 被引量:2
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作者 康顺 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1990年第5期489-495,共7页
Based on the working of Lighthill and Hunt et al., in the present paper the author has established the topological rules adapting to analysing the skin-friction lines and the section streamlines in cascades. These rul... Based on the working of Lighthill and Hunt et al., in the present paper the author has established the topological rules adapting to analysing the skin-friction lines and the section streamlines in cascades. These rules are (1) for a rotor cascade without shroud band, the total number of nodal points equals that the saddle points on the skin-friction line vector fields in eachpitch range; (2) for an annular or straight cascade with no-clearances at blade ends, the total number of saddle points is two more than that of nodal points on the skin-friction line fields in a pitch; (3) the total number of saddles in the secondary flow fields on cross-sections in cascade is one less than that of nodes; (4) in the section streamline vector fields on a meridian surface penetrating a flow passage, and on leading and trailing edge sections, the total number of nodes is equal to that of saddles; (5) on the streamline vector fields of a blade-to-blade surface, the total number of nodes is one less than that of saddles. 展开更多
关键词 node TOPOLOGICAL RULES FOR SKIN-FRICTION lineS AND SECTION STREAMlineS AN APPLICATION OF TOPOLOGICAL analysis TO STUDYING THE THREE-DIMENSIONAL FLOW IN CASCADES PART I
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Interspecific Chromosome Substitution Lines as Genetic Resources for Improvement,Trait Analysis and Genomic Inference 被引量:1
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作者 RASKA Dwaine A SAHA Sukumar JENKINS Johnie N MCCARTY Jack C STELLY David M 《棉花学报》 CSCD 北大核心 2008年第S1期84-,共1页
The genetic base that cotton breeders commonly use to improve Upland cultivars is very narrow.The AD-genome species Gossypium barbadense,G.tomentosum,and G.mustelinum are part of
关键词 CS Interspecific Chromosome Substitution lines as Genetic Resources for Improvement Trait analysis and Genomic Inference
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Dynamic Analysis of Overhead Transmission Lines under Turbulent Wind Loading 被引量:2
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作者 Alok Dua Mathias Clobes +1 位作者 Thomas Hobbel Vasant Matsagar 《Open Journal of Civil Engineering》 2015年第4期359-371,共13页
Transmission tower-line systems are designed using static loads specified in various codes. This paper compares the dynamic response of a test transmission line with the response due to static loads given by Eurocode.... Transmission tower-line systems are designed using static loads specified in various codes. This paper compares the dynamic response of a test transmission line with the response due to static loads given by Eurocode. Finite element design software SAP2000 was used to model the towers and lines. Non-linear dynamic analysis including the large displacement effects was carried out. Macroscopic aspects of wind coherence along element length and integration time step were investigated. An approach is presented to compare the probabilistic dynamic response due to 7 different stochastically simulated wind fields with the response according to EN-50341. The developed model will be used to study the response recorded on a test line due to the actual wind speed time history recorded. It was found that static load from EN overestimated the strength of conductor cables. The response of coupled system considering towers and cables was found to be different from response of only cables with fixed supports. 展开更多
关键词 Dynamic analysis Finite Element Method SAP2000 Transmission Towers Transmission lines
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