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基于多任务学习的同行评审细粒度情感分析模型 被引量:1
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作者 朱金秋 檀健 +1 位作者 韩斌彬 殷秀秀 《中北大学学报(自然科学版)》 CAS 2024年第1期105-113,共9页
学术论文同行评审能够直接反映审稿人对论文的主观评价,对审稿文本进行情感分析有利于挖掘审稿人对论文多维度的评价信息。现有的情感分析模型仅能挖掘专家单一的评审维度和相应的情感倾向,本文提出了一种基于多任务学习的同行评审细粒... 学术论文同行评审能够直接反映审稿人对论文的主观评价,对审稿文本进行情感分析有利于挖掘审稿人对论文多维度的评价信息。现有的情感分析模型仅能挖掘专家单一的评审维度和相应的情感倾向,本文提出了一种基于多任务学习的同行评审细粒度情感分析模型。该模型在多任务学习框架下,通过在BERT-LCF模型的基础上增加BiLSTM-CRF模块,使其具备了同时完成属性词抽取和细粒度情感分析任务的能力。与传统的基于Pipeline模式的单任务细粒度情感分析模型相比,本模型在保证精度的情况下可以同时完成评审属性提取和情感分析任务。在这两项任务中,所提出模型的F1分数分别达到了89.01%和90.71%。对比实验证明,在多任务场景下,引入BiLSTM-CRF模块对评审文本属性词提取任务有一定的提升作用。 展开更多
关键词 同行评审 多任务学习 属性词抽取 细粒度情感 BiLSTM-CRF
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Scoring and Consequential Validity Evidence of Computer-and Paper-Based Writing Tests in Times of Change
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作者 María GUAPACHA-CHAMORRO Orlando CHAVES-VARÓN 《Chinese Journal of Applied Linguistics》 2024年第3期450-480,525,共32页
Little is known about how the assessment modality,i.e.,computer-based(CB)and paper-based(PB)tests,affects language teachers’scorings,perceptions,and preferences and,therefore,the validity and fairness of classroom wr... Little is known about how the assessment modality,i.e.,computer-based(CB)and paper-based(PB)tests,affects language teachers’scorings,perceptions,and preferences and,therefore,the validity and fairness of classroom writing assessments.The present mixed-methods study used Shaw and Weir’s(2007)sociocognitive writing test validation framework to examine the scoring and consequential validity evidence of CB and PB writing tests in EFL classroom assessment in higher education.Original handwritten and word-processed texts of 38 EFL university students were transcribed to their opposite format and assessed by three language lecturers(N=456 texts,152 per teacher)to examine the scoring validity of CB and PB tests.The teachers’perceptions of text quality and preferences for assessment modality accounted for the consequential validity evidence of both tests.Findings revealed that the assessment modality impacted teachers’scorings,perceptions,and preferences.The teachers awarded higher scores to original and transcribed handwritten texts,particularly text organization and language use.The teachers’perceptions of text quality differed from their ratings,and physical,psychological,and experiential characteristics influenced their preferences for assessment modality.The results have implications for the validity and fairness of CB and PB writing tests and teachers’assessment practices. 展开更多
关键词 scoring validity consequential validity CB and PB writing tests classroom assessment
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Cluster Analysis of Characteristics of Different Sweet Cherry Varieties
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作者 杨晓华 尹蓉 +6 位作者 庞传明 聂国伟 张倩茹 李凯 茹慧玲 籍艺文 段泽敏 《Agricultural Science & Technology》 CAS 2015年第11期2441-2445,共5页
In order to compare the characteristics of different varieties of sweet cherry and to formulate corresponding pruning scheme, hierarchical cluster analysis was conducted for the 14 sweet cherry varieties that were mai... In order to compare the characteristics of different varieties of sweet cherry and to formulate corresponding pruning scheme, hierarchical cluster analysis was conducted for the 14 sweet cherry varieties that were mainly planted in Shanxi Province. The results showed that the 14 varieties of sweet cherry could be divided into two types, Hongmanao and Rainier. Fruit setting rate, branching rate, medium fruit shoot proportion, spur proportion and yield per plant were significantly different between these two types of sweet cherry. The key points of pruning management, to improve the yield of Rainier type, were to increase the fruit setting rate and spur proportion, and to control properly the long and medium fruit shoot proportion. 展开更多
关键词 Sweet cherry Fruit-bearing branch group Cluster analysis YIELD
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Analysis on Fuji Apple Tree Structures and Related Factors under Different Pruning Modes 被引量:1
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作者 郝婕 索相敏 +4 位作者 李学营 魏亮 王献革 鄢新民 冯建忠 《Agricultural Science & Technology》 CAS 2017年第12期2528-2531,2535,共5页
To determine the correlations between the tree structuresof Fuji apple with different pruning modes and each factor, the data about 3 tree structures which were free spindle short shoot, free spindle long shoot and sl... To determine the correlations between the tree structuresof Fuji apple with different pruning modes and each factor, the data about 3 tree structures which were free spindle short shoot, free spindle long shoot and slenderspindle short shoot in Xingtang County of Hebai Province were investigated, then by SPSS anal- ysis, the correlations between the taperingness and each growth factor of inserted small branch were compared. The results showed that the taperingness of central trunk of free spindle dwarf-shoot Fuji apple treeshad negative correlations with each factor of inserted small branch, while the taperingness of central trunk of free spin- dle long-shoot Fuji apple treeshad positive correlations with each factor of inserted small branch, the taperingness of central trunk of slenderspindle short-shootFuji ap- ple treeshad negative correlation with total thickness of inserted small branch, but had positive correlations with other factors. This study can provide a scientifictheo- retical basis for the pruning technology of high-density planting trees grafting by dwarfing self-rooted rootstock. 展开更多
关键词 PRUNING Fuji apple Tree structures Analysis of related factors
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Analysis on Apple Tree Structures by Free Spindle Pruning Mode
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作者 郝婕 索相敏 +3 位作者 李学营 王献革 鄢新民 冯建忠 《Agricultural Science & Technology》 CAS 2016年第10期2238-2241,共4页
To determine the correlation between the stem taperingness and central shaft by free spindle pruning mode on different apple cultivars, the central shaft growth data of three cultivars of free spindle short shoot "F... To determine the correlation between the stem taperingness and central shaft by free spindle pruning mode on different apple cultivars, the central shaft growth data of three cultivars of free spindle short shoot "Fuji", free spindle long shoot "Fuji", free spindle "Huaguan" were investigated in Xingtang County of Hebei Province by SPSS analysis. The results showed that the stem taperingness on free spindle short shoot "Fuji" was in negative correlation with central shaft, but the correlation was not significant. While the stem taperingness on free spindle long shoot "Fuji" was in positive correlation with central shaft, but the correlation was not significant either. The stern taperingness on free spindle "Huaguan" was in negative correlation with central shaft, and the correlation between the stem taperingness and the central shaft total length was significant at the level of 0.01. The results.provided scientific theoretical basis for guiding the dwarfing rootstocks close planting apple tree pruning technology. 展开更多
关键词 APPLE Free spindle pruning mode Structure analysis
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特殊狗肉
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作者 柯云 《经贸导刊》 1996年第2期47-47,共1页
关键词 狗肉 工作关系 小小说 结果分 王八 主系 山珍 夜谈 欠人 天方
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"一"不变应万变
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作者 刘然 《小学生(低幼版)》 2005年第2期70-73,共4页
关键词 结果分 说不出 书生 江湖
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容城人行实行等级金融机构管理制度
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作者 杨满才 《河北金融》 1996年第10期21-21,共1页
容城县人民银行十分重视依法监管金融机构。1996年他们在归口管理办法的基础上又推出等级管理办法。 等级管理办法是每年对金融机构考评一次,考评结果分为三级,按信贷、结算、现金百分评比。90分—100分为一级,80分—90分为二级。
关键词 金融机构管理 行实 等级管理 人民银行 考评 辖区金融机构 依法监管 归口管理 制度 结果分
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提高雏鸡抵抗力的添加剂
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作者 李琼璋 《畜牧兽医科技信息》 2001年第7期6-6,共1页
取肉鸡分成2组,每组300羽,试验组在头10天内每天20mg/kg体重的用量把琥珀酸盐混入饲料中喂饲。结果显示:在琥珀酸的作用下,21日龄以上的雏鸡血清中溶菌酶的活性较对照组高出2、3倍以上;测定60日龄雏鸡的肝匀浆时,对照组和试验组的结果... 取肉鸡分成2组,每组300羽,试验组在头10天内每天20mg/kg体重的用量把琥珀酸盐混入饲料中喂饲。结果显示:在琥珀酸的作用下,21日龄以上的雏鸡血清中溶菌酶的活性较对照组高出2、3倍以上;测定60日龄雏鸡的肝匀浆时,对照组和试验组的结果分别是: 展开更多
关键词 雏鸡 脂蛋白 机体抵抗力 毫克 试验组 脂酶活性 酶的活性 肝匀浆 结果分 甘油三酸脂
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基于小波消噪的EMD模型在GPS振动信号处理中的应用 被引量:4
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作者 李旋 孙磊 +2 位作者 骆辉 戴吾蛟 何伟 《工程勘察》 CSCD 北大核心 2011年第3期72-76,共5页
经验模式分解和小波分解是当前有效处理非平稳信号的两种时频分析方法,它们各具有其优缺点,适用于不同的应用。从对GPS振动信号的预处理、时域和频域处理入手,结果分析表明,对GPS振动信号先进行小波滤波消除随机噪声的干扰,再应用经验... 经验模式分解和小波分解是当前有效处理非平稳信号的两种时频分析方法,它们各具有其优缺点,适用于不同的应用。从对GPS振动信号的预处理、时域和频域处理入手,结果分析表明,对GPS振动信号先进行小波滤波消除随机噪声的干扰,再应用经验模式分解更有利于变形特征信息的分离和提取,提取的信号与振动平台记录数据更加吻合。 展开更多
关键词 经验模式解(EMD) 小波解(WD) 全球定位系统 振动变形
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The Definition and Classification of Extensive and Persistent Extreme Cold Events in China 被引量:40
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作者 PENG Jing-Bei BUEH Cholaw 《Atmospheric and Oceanic Science Letters》 2011年第5期281-286,共6页
Using the observed daily temperatures from 756 stations in China during the period from 1951 to 2009 extensive and persistent extreme cold events (EPECEs) were defined according to the following three steps:1) a stati... Using the observed daily temperatures from 756 stations in China during the period from 1951 to 2009 extensive and persistent extreme cold events (EPECEs) were defined according to the following three steps:1) a station was defined as an extreme cold station (ECS) if the observed temperature was lower than its 10th percentile threshold;2) an extensive extreme cold event was determined to be present if the approximated area occupied by the ECSs was more than 10% of the total area of China (83rd percentile) on its starting day and the maximum area occupied by the ECSs was at least 20% of the total area of China (96th percentile);and 3) an EPECE was determined to be present if the extensive extreme cold event lasted for at least for eight days.52 EPECEs were identified in this manner,and these identification results were also verified using other reliable data.On the basis of cluster analysis,five types of EPECEs were classified according to the spatial distribution of ECSs at their most extensive time over the course of the EPECE. 展开更多
关键词 EPECE percentile cluster analysis
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Assignments of ~1H and ^(13)C NMR Signals of Mogroside Ⅳa 被引量:3
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作者 ZHANGJian-ye YANGXiu-wei 《Journal of Chinese Pharmaceutical Sciences》 CAS 2003年第4期196-200,共5页
Aim To investigate the structure of mogroside Ⅳa isolated from traditionalChinese medicine fructus mo-mordicae [fruits of Siraitia grosvenori (Swingle) C. Jeffery] andsummarize the NMR characteristics of the structur... Aim To investigate the structure of mogroside Ⅳa isolated from traditionalChinese medicine fructus mo-mordicae [fruits of Siraitia grosvenori (Swingle) C. Jeffery] andsummarize the NMR characteristics of the structure. Methods Common extraction, separation andpurification methods were used. Various NMR techniques including ~1H NMR, ^(13)C NMR, DEPT, ~1H-~1HCOSY, HSQC, HMBC, NOESY and molecular model simulated by computer were used to elucidate thestructure. Results ~1H and ^(13)C NMR signals of mogroside Ⅳa were assigned, and spectroscopicbasis was obtained for identification of such type of compounds. Conclusion 1D and 2D NMR techniquesincluding ~1H-~1H COSY, HSQC, HMBC, NOESY spectra are powerful tools for structure analysis. Thestructure determined by NMR methods is identical with energy minimized conformation simulated bycomputer. 展开更多
关键词 fructus momordicae mogroside Ⅳa triterpenoid saponin NMR spectrum ASSIGNMENT
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Microsurgical efficacy in 326 children with tethered cord syndrome: a retrospective analysis 被引量:7
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作者 Ai-Jia Shang Chang-Hao Yang +4 位作者 Cheng Cheng Ben-Zhang Tao Yuan-Zheng Zhang Hai-Hao Gao Shao-Cong Bai 《Neural Regeneration Research》 SCIE CAS CSCD 2019年第1期149-155,共7页
Tethered cord syndrome is a progressive disease with a typically insidious onset in infants and children, and which can lead to persistent progress of neurological deficits and a high rate of disability without timely... Tethered cord syndrome is a progressive disease with a typically insidious onset in infants and children, and which can lead to persistent progress of neurological deficits and a high rate of disability without timely intervention. The purpose of this study was to investigate the curative effect of microsurgery in children with different types of tethered cord syndrome. In this study, we analyzed 326 patients with tethered cord syndrome, aged from 2 months to 14 years old, who were followed for 3-36 months after microscopic surgery. Based on clinical manifestations and imaging findings, these patients were classified into five types: tight ilium terminale (53 cases), lipomyelome- ningocele (55 cases), lipomatous malformation (124 cases), postoperative adhesions (56 cases), and split cord malformation (38 cases). All patients underwent microsurgery. Curative effects were measured before and 3 months after surgery by Spina Bifida Neurological Scale based on sensory and motor functions, reflexes, and bladder and bowel function. The results showed that Spina Bifida Neurological Scale scores improved in all five types after surgery. Overall effective rates in these patients were 75%. Effective rates were 91% in tight ilium terminale, 84% in lipomyelomeningocele, 65% in lipomatous malformation, 75% in postoperative adhesion, and 79% in split cord mal- formation. Binary logistic regression analysis revealed that types of tethered cord syndrome (lipoma-type or not) and symptom duration before surgery were independent influencing factors of surgical outcome. These results show that therapeutic effect is markedly different in patients with different types of tethered cord syndrome. Suitable clinical classification for tethered cord syndrome will be helpful in predicting prognosis and guiding treatment. This trial has been registered in the Chinese Clinical Trial Registry (registration number: ChiCTR1800016464). 展开更多
关键词 nerve regeneration tethered cord syndrome SURGERY THERAPY PROGNOSIS children patients surgical outcome surgical methods prophylactic surgery spina bifida neural regeneration
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Characteristics of supersonic flow in new type externally pressurized spherical air bearings 被引量:2
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作者 WANG Fu-sheng BAO Gang 《Journal of Central South University》 SCIE EI CAS 2012年第1期128-134,共7页
In order to predict accurately the characteristics of supersonic flow in new type externally pressurized spherical air bearings under large bearing clearance and high air supply pressure, which could decrease their lo... In order to predict accurately the characteristics of supersonic flow in new type externally pressurized spherical air bearings under large bearing clearance and high air supply pressure, which could decrease their load carrying capacity and stability, a CFD-based analysis was introduced to solve the three-dimensional turbulent complete compressible air flow governing equations. The realizable κ-ε model was used as a turbulent closure illustrate that the interaction exists between shock waves The supersonic flow field near air inlets was analyzed. The flow structures and boundary layer, and the flow separation is formed at the lower comer and the lower wall around the point of a maximum velocity. The numerical results show that the conversion from supersonic flow to subsonic flow in spherical air bearing occurs through a shock region (pseudo-shock), and the viscous boundary layer results in the flow separation and reverse flow near the shock. The calculation results basically agree with the corresponding experimental data. 展开更多
关键词 supersonic flow spherical air bearings Mach number shock wave
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An integrated method to calculate the spatial distribution of overburden strata failure in longwall mines by coupling GIS and FLAC^(3D) 被引量:15
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作者 Zhao Xiaodong Jiang Jian Lan Bochao 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2015年第3期369-373,共5页
The spatial distribution of overburden strata failure is of significant importance to affect the safety of underground mining. Because the traditional methods cannot be applied in all coal mines due to geological cond... The spatial distribution of overburden strata failure is of significant importance to affect the safety of underground mining. Because the traditional methods cannot be applied in all coal mines due to geological conditions or mining structures, a method of coupling FLAC3D with GIS was presented to calculate the spatial distribution of overburden strata failure in longwall coal mines. After building the spatio-temporal database from the calculation results of FLAC3D, the height of the mining-induced fractured zone in the overburden strata can be calculated by using the given height function. The results of case study show that the height of the fractured zone reached the maximum value at the face advance equal to about the panel width. The outcome of the work presented will be helpful in practice to improve safety in the production. 展开更多
关键词 GIS Overburden strata Spatial modeling Coupling
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Biomarkers and potential pathogenesis of colorectal cancer-related ischemic stroke 被引量:6
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作者 Qi-Xiong Qin Xue-Min Cheng +8 位作者 Li-Zhi Lu Yun-Fei Wei Da-Cheng Wang Hai-Hua Li Guo-Hui Li Hong-Bin Liang Sheng-Yu Li Li Chen Zhi-Jian Liang 《World Journal of Gastroenterology》 SCIE CAS 2018年第43期4950-4958,共9页
AIM To investigate the specific biomarkers and potential pathogenesis of colorectal cancer-related ischemic stroke(CRCIS).METHODS A retrospective study was conducted on CRCIS patients(colorectal cancer patients with i... AIM To investigate the specific biomarkers and potential pathogenesis of colorectal cancer-related ischemic stroke(CRCIS).METHODS A retrospective study was conducted on CRCIS patients(colorectal cancer patients with ischemic stroke without conventional stroke risk factors) registered at seven centers between January 2007 and December 2017. Clinical data and laboratory and imaging findings were compared with age-and sex-matched patients with colorectal cancer(CRC) without ischemic stroke that were admitted to the same hospital during the same period. Univariate and multivariate analyses were performed to analyze the independent risk factors for CRCIS. A receiver operator characteristic curve was configured to calculate the optimal cut-off value of the products of the independent risk factors for CRCIS. RESULTS A total of 114 CRCIS patients and 114 CRC patients were included. Multiple lesions in multiple vascular territories were common in CRCIS patients(71, 62.28%). The levels of plasma D-dimer, carcinoembryonic antigen(CEA), cancer antigen 125, and neutrophil count were significantly higher in CRCIS patients than in CRC patients. Multiple logistic regression analysis revealed that plasma D-dimer levels [odds ratio(OR) = 1.002, 95% confidence interval(CI): 1.001-1.003, P < 0.001], CEA levels(OR = 1.011, 95%CI: 1.006-1.015, P < 0.001), and neutrophil count levels(OR = 1.626, 95%CI: 1.268-2.087, P < 0.001) were independent risk factors for CRCIS. In addition, receiver operator characteristic curve revealed that the area under curve for the products of plasma D-dimer, CEA, and neutrophil count was 0.889 ± 0.022(95%CI: 0.847-0.932, P < 0.001), and the optimal cut-off value for the product was 252.06, which was called the CRCIS Index, with a sensitivity of 86.0% and specificity of 79.8%.CONCLUSION Hypercoagulability induced by elevated CEA and neutrophils may be an important cause of CRCIS. The CRCIS index, which serves as a biomarker of CRCIS, needs further study. 展开更多
关键词 Colorectal cancer Ischemic stroke BIOMARKER PATHOGENESIS
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Separation of Eu^3+ Using a Novel Dispersion Combined Liquid Membrane with P507 in Kerosene as the Carrier 被引量:4
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作者 裴亮 王理明 付兴隆 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2011年第1期33-39,共7页
The separation of Eu^3 +is studied with a dispersion combined liquid membrane(DCLM),in which polyvinylidene fluoride membrane(PVDF)is used as the liquid membrane support,dispersion solution containing HCl solutio... The separation of Eu^3 +is studied with a dispersion combined liquid membrane(DCLM),in which polyvinylidene fluoride membrane(PVDF)is used as the liquid membrane support,dispersion solution containing HCl solution as the stripping solution,and 2-ethyl hexyl phosphonic acid-mono-2-ethyl hexyl ester(P507)dissolved in kerosene as the membrane solution.The effects of pH value,initial concentration of Eu3 +and different ionic strength in the feed phase,volume ratio of membrane solution to stripping solution,concentration of HCl solution, concentration of carrier,different stripping agents in the dispersion phase on the separation are investigated.The optimum condition for separation of Eu3 +is that concentration of HCl solution is 4.0 mol·L 1,concentration of carrier is 0.16 mol·L 1,and volume ratio of membrane solution to stripping solution is 30︰30 in the dispersion phase, and pH value is 4.2 in the feed phase.The ionic strength has no significant effect on separation of Eu3 +.Under the optimum condition,when the initial concentration of Eu3 +is 0.8×10 4mol·L 1,the separation percentage of Eu 3+is 95.3%during the separation time of 130 min.The kinetic equation is developed in terms of the law of mass diffusion and the theory of interface chemistry.The diffusion coefficient of Eu3 +in the membrane and the thickness of diffusion layer between feed phase and membrane phase are obtained and their values are 1.48×10 7m 2·s 1and 36.6μm,respectively.The results obtained are in good agreement with literature data. 展开更多
关键词 dispersion combined liquid membrane 2-ethyl hexyl phosphonic acid-mono-2-ethyl hexyl ester SEPARATION europium3
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B→ρ(ω,φ)η(′)Decays and NLO Contributions in pQCD Approach 被引量:1
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作者 ZHANG Zhi-Qing XIAO Zhen-Jun 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第5期885-894,共10页
By employing the perturbative QCD (pQCD) factorization approach, we calculate some important next- to-leading-order (NLO) contributions to the two-body charmless hadronic decays B^+ →ρ^+η(') and B^0 → ρ^... By employing the perturbative QCD (pQCD) factorization approach, we calculate some important next- to-leading-order (NLO) contributions to the two-body charmless hadronic decays B^+ →ρ^+η(') and B^0 → ρ^0(ω, φ)η('), induced by the vertex QCD corrections, the quark-loops as well as the chromo-magnetic penguins. From the numerical results and phenomenological analysis we find that (a) for B^± → ρ^±η(') (B^0 → ρ^0(ω, φ)η(')decays, the partial NLO contributions to branching ratios are small (large) in magnitude; and (b) the pQCD predictions for ACP^dir(B^± → ρ^±η(')) are consistent with the data, while the predicted .ACP(B^0 → ρ^0(ω)η(')) are generally large in magnitude and could be tested by the forthcoming LHCb experiments. 展开更多
关键词 pQCD factorization approach B meson decays branching ratio CP-violating asymmetry
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Risk factors for rebleeding after angiographically negative acute gastrointestinal bleeding 被引量:2
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作者 Ijin Joo Hyo-Cheol Kim +2 位作者 Jin Wook Chung Hwan Jun Jae Jae Hyung Park 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第32期4023-4027,共5页
AIM:To identify possible predictive factors for rebleeding after angiographically negative findings in patients with acute non-variceal gastrointestinal bleeding.METHODS: From January 2000 to July 2007, 128 patients w... AIM:To identify possible predictive factors for rebleeding after angiographically negative findings in patients with acute non-variceal gastrointestinal bleeding.METHODS: From January 2000 to July 2007, 128 patients with acute non-variceal gastrointestinal bleeding had negative f indings after initial angiography. Clinical and laboratory parameters were analyzed retrospectively.RESULTS: Among 128 patients, 62 had no recurrent gastrointestinal bleeding and 66 had recurrent gastrointestinal bleeding within 30 d. As determined by the use of multivariate analysis, an underlying malignancy, liver cirrhosis and hematemesis were significant factors related to recurrent gastrointestinal bleeding.CONCLUSION: Clinical factors including underlying malignancy, liver cirrhosis, and hematemesis are important predictors for rebleeding after angiographically negative findings in patients with acute non-variceal gastrointestinal bleeding. 展开更多
关键词 ANGIOGRAPHY Gastrointestinal hemorrhage Predictive factor
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Temperature Stress Analysis of Prestressed Concrete Box Girder with Corrugated Steel Webs 被引量:5
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作者 单成林 刘文芳 《Transactions of Tianjin University》 EI CAS 2012年第2期97-103,共7页
To figure out the distribution of temperature gradient along the girder height of steel-concrete composite box girder, combined with the mechanical characteristics of prestressed concrete composed box girder with corr... To figure out the distribution of temperature gradient along the girder height of steel-concrete composite box girder, combined with the mechanical characteristics of prestressed concrete composed box girder with corrugated steel webs, the calculation formulas of cross-sectional temperature stress along the span in a simply-supported beam bridge with composite section were derived under the conditions of static equilibrium and deformation compatibility of the beam element. The methods of calculating the maximum temperature stress value were discussed when the connectors are assumed rigid or flexible. Theoretical and numerical results indicate that the method proposed shows better precision for the calculation of temperature self-stress in both the top and the bottom surfaces of the box girder. Moreover, the regularity of temperature stress distribution at different locations along the girder span is that the largest axial force of the top or the bottom plate of the box girder is located in the midspan and spreads decreasingly until zero at both supported ends, and that the greatest longitudinal shear density in steel-concrete interface appears at both supported ends and then reduces gradually to zero in the midspan. 展开更多
关键词 bridge engineering composite structure temperature effect corrugated steel web connector influence
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