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Cloning of a MADS Box Gene(GhMADS3)from Cotton and Analysis of Its Homeotic Role in Transgenic Tobacco 被引量:8
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作者 郭余龙 祝钦泷 +1 位作者 郑尚永 李名扬 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第6期527-535,共9页
A MADS box gene (GhMADS3) was cloned from cotton (Gossypium hirsutum L.) based on EST sequences. The predicted protein sequence of GhMADS3 showed 85%, 73%, and 62% identity with Theobroma cacao TcAG, Antirrhinum m... A MADS box gene (GhMADS3) was cloned from cotton (Gossypium hirsutum L.) based on EST sequences. The predicted protein sequence of GhMADS3 showed 85%, 73%, and 62% identity with Theobroma cacao TcAG, Antirrhinum majus FAR, and Arabidopsis thaliana AG, respectively, and was grouped with AG homologues when the full length sequences excluding N-extensions were compared. GhMADS3 expressed in the wild type cotton flower primarily in stamens and carpels, which was comparable to AG in Arabidopsis. However, it was not expressed in floral buds of a homeotic cotton variant chvl. Ectopic expression of GhMADS3 in tobacco (Nicotiana tabacum L.) resulted in flowers with sepal-to-carpel and petal-to-stamen transformation. The carpelloid first whorl organs, with stigmatic tissue on their upper edges, had a white appearance when compared with the dark green color of the wild type sepals. At times, long filaments were observed at the fusion site of the first carpelloid oranges. The second whorl organs in staminoid were usually smaller than the wild type and the color was changed from pink to white. These results suggest that GhMADS3 has a homeotic role in flower development. 展开更多
关键词 MADS-BOX AG subfamily homeotic role COTTON flower development
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Description of E4 Transitions in A=192,194,196,198 Platinum Isotopes in a Microscopic sdgIBM—1
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作者 ZHANGZhan-Jun YANGJie 等 《Communications in Theoretical Physics》 SCIE CAS CSCD 2001年第6期711-716,共6页
Influence of the effective fermion hexadecapole force newly incorporated in a microscopic sdgIBM-1 on spectra, reduced E2 and E4 transition matrix elements (T(E2)s and T(E4)s) in the even-even platinum isotopes (A = 1... Influence of the effective fermion hexadecapole force newly incorporated in a microscopic sdgIBM-1 on spectra, reduced E2 and E4 transition matrix elements (T(E2)s and T(E4)s) in the even-even platinum isotopes (A = 192,194,196,198) is investigated in terms of numerical calculations. It is found that the introduced interaction causes only limited modification to the spectrum and T(E2)s, apart from a few exceptions. However, it plays an essential role in describing E4 transitions. Thus in the case that the interaction is incorporated with certain strength, a reasonable description of all the E4 transitions in the platinum isotopes is reached in the microscopic sdgIBM-1 in comparing both to experimental data and the results calculated in phenomenological boson model. 展开更多
关键词 hexadecapole force microscopic sdgIBM-1 E4 transition
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A Probabilistic Rating Prediction and Explanation Inference Model for Recommender Systems 被引量:3
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作者 WANG Hanshi FU Qiujie +1 位作者 LIU Lizhen SONG Wei 《China Communications》 SCIE CSCD 2016年第2期79-94,共16页
Collaborative Filtering(CF) is a leading approach to build recommender systems which has gained considerable development and popularity. A predominant approach to CF is rating prediction recommender algorithm, aiming ... Collaborative Filtering(CF) is a leading approach to build recommender systems which has gained considerable development and popularity. A predominant approach to CF is rating prediction recommender algorithm, aiming to predict a user's rating for those items which were not rated yet by the user. However, with the increasing number of items and users, thedata is sparse.It is difficult to detectlatent closely relation among the items or users for predicting the user behaviors. In this paper,we enhance the rating prediction approach leading to substantial improvement of prediction accuracy by categorizing according to the genres of movies. Then the probabilities that users are interested in the genres are computed to integrate the prediction of each genre cluster. A novel probabilistic approach based on the sentiment analysis of the user reviews is also proposed to give intuitional explanations of why an item is recommended.To test the novel recommendation approach, a new corpus of user reviews on movies obtained from the Internet Movies Database(IMDB) has been generated. Experimental results show that the proposed framework is effective and achieves a better prediction performance. 展开更多
关键词 collaborative filtering recommendersystems rating prediction sentiment analysis matrix factorization recommendation explanation
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Application of homotopy parameter inversion method in Miyun Reservoir
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作者 LI Xin LI Yong CHEN Duowei 《Global Geology》 2009年第2期109-111,共3页
The large-scale convergence of homotopy parametric inversion method on the water quality model parameters calculated was used,with application in parametric inversion calculation of total phosphorus of Beijing Miyun R... The large-scale convergence of homotopy parametric inversion method on the water quality model parameters calculated was used,with application in parametric inversion calculation of total phosphorus of Beijing Miyun Reservoir.Through calculated and compared the error of sedimentation rate by homotopy parametric inversion method and genetic inversion calculation method,the results indicate that homotopy parametric inversion method has good stability,calculating speed,and even if the initial selection away from the objective function,the solution still has a good convergence. 展开更多
关键词 Water quality model REVERSION extensiveness convergence HOMOTOPY genetic inversion method objective function
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Dual regulatory role for phosphatase and tensin homolog in specification of intestinal endocrine cell subtypes
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作者 Sébastien AB Roy Marie-Josée Langlois +3 位作者 Julie C Carrier Franois Boudreau Nathalie Rivard Nathalie Perreault 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第14期1579-1589,共11页
AIM:To investigate the impact of phosphatase and tensin homolog(Pten) in the specification of intestinal enteroendocrine subpopulations.METHODS:Using the Cre/loxP system,a mouse with conditional intestinal epithelial ... AIM:To investigate the impact of phosphatase and tensin homolog(Pten) in the specification of intestinal enteroendocrine subpopulations.METHODS:Using the Cre/loxP system,a mouse with conditional intestinal epithelial Pten deficiency was generated.Pten mutant mice and controls were sacrificed and small intestines collected for immunofluorescence and quantitative real-time polymerase chain reaction.Blood was collected on 16 h fasted mice by cardiac puncture.Enzyme-linked immunosorbent assay was used to measure blood circulating ghrelin,somatostatin(SST) and glucose-dependent insulinotropic peptide(GIP) levels.RESULTS:Results show an unexpected dual regulatory role for epithelial Pten signalling in the specification/differentiation of enteroendocrine cell subpopulations in the small intestine.Our data indicate that Pten positively regulates chromogranin A(CgA) expressing subpopulations,including cells expressing secretin,ghrelin,gastrin and cholecystokinin(CCK).In contrast,Pten negatively regulates the enteroendocrine subtype specification of non-expressing CgA cells such as GIP and SST expressing cells.CONCLUSION:The present results demonstrate that Pten signalling favours the enteroendocrine progenitor to specify into cells expressing CgA including those producing CCK,gastrin and ghrelin. 展开更多
关键词 Phosphatase and tensin homolog Enteroendocrine cells Intestinal epithelial cell specification Chromogranin A
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Field analysis of metallogenic information and its application 被引量:3
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作者 毛先成 胡超 +3 位作者 周尚国 张宝一 汪凡云 曾文波 《Journal of Central South University》 SCIE EI CAS 2011年第1期196-207,共12页
Focusing on the issue to deal with inadequate extraction of metallogenic information especially geological information,a new method of extracting metallogenic information based on field model,i.e.the field analysis me... Focusing on the issue to deal with inadequate extraction of metallogenic information especially geological information,a new method of extracting metallogenic information based on field model,i.e.the field analysis method of metallogenic information,was proposed.In addition,a case study by using the method of the extraction of metallogenic information from the west Guangxi and southeast Yunnan district as an example was performed.The representation method for the field models of metallogenic information,including the metallogenic influence field model and the metallogenic distance field model,was discussed by introducing the concept of the field theory,based on the characteristic analysis of the distance gradualness and the influence superposition of metallogenic information.According to the field theory superposition principle and the spatial distance analysis method,the mathematical models for the metallogenic influence field and the metallogenic distance field of point,line and area geological bodies were derived out by using parameter equation and calculus.Based on the metallogenic background analysis,the metallogenic information field models of synsedimentary faults and manganese sedimentary basins were built.The relationship between the metallogenic information fields and the manganese mineralization distribution was also investigated by using the method of metallogenic information field analysis.The instance study indicates that the proposed method of metallogenic information field analysis is valid and useful for extracting the ore-controlling information of synsedimentary faults and manganese sedimentary basins in the study area,with which the extraction results are significant both statistically and geologically. 展开更多
关键词 metallogenic information field model metallogenic prognosis manganese ore
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The Double Excitation: A Solution to Improve Energetic Performances of High Power Synchronous Machines
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作者 Aymen Ammar Frederic Gillon Pascal Brochet 《Journal of Energy and Power Engineering》 2012年第5期719-724,共6页
DFSM (doubly fed synchronous machine) presents several advantages such as efficiency improvement, weight reduction and increase of the utilization factor (kW/kg). In this paper the authors focus on impact of the D... DFSM (doubly fed synchronous machine) presents several advantages such as efficiency improvement, weight reduction and increase of the utilization factor (kW/kg). In this paper the authors focus on impact of the DFSM on the efficiency and machine weight in comparison to conventional synchronous generator with wound rotor. Different topologies of DFSM are briefly described and the different methods and models for performances prediction are presented. 展开更多
关键词 Double excitation LOSSES no load characteristic permanent magnet reluctances network vector diagram.
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Analysis and clinical applications of metabolic syndrome risk factors for cardiovascular
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作者 Li Wu Xiaochun Zhang 《International Journal of Technology Management》 2014年第2期84-86,共3页
Metabolic syndrome had many different names, including syndrome X, insulin resistance syndrome. At present the cause of metabolic syndrome is unclear, it may come from two aspects: First, acquired, including being ov... Metabolic syndrome had many different names, including syndrome X, insulin resistance syndrome. At present the cause of metabolic syndrome is unclear, it may come from two aspects: First, acquired, including being overweight or obese, reduced physical activity and excessive carbohydrate diet; Second, genetic factors, involving multiple genes, not yet fully elucidated. The syndrome is generally believed to be the collection of a variety of cardiovascular risk factors caused by poor lifestyle under the genetic background, including hypertension, dyslipidemia, abdominal obesity, hyperinsulinemia, microalbuminuria, hypercoagulable state, hyperhomocysteinemia and so on. Hyperinsulinemia and insulin resistance is the central link, which is closely related to dyslipidemia, impaired glucose tolerance, and abdominal obesity. Metabolic syndrome may eventually lead to atherosclerosis: coronary artery disease, myocardial infarction, stroke, peripheral vascular disease and endothelial dysfunction. In 1999, the working definition of World Health Organization (WHO) to the metabolic syndrome is: glucose regulation impairment or diabetes, and / or insulin resistance, accompanied by the other two items or more ingredients, such as hypertension, high triglycerides esters hyperlipidemia and / or low HDL cholesterol, central obesity or microalbuminuria. 展开更多
关键词 Metabolic syndrome CLINICAL risk factors CARDIOVASCULAR
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汉语的人称代词复数表示法 被引量:31
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作者 李蓝 《方言》 CSSCI 北大核心 2008年第3期224-243,共20页
本文首先确定人称代词复数表示法的类型参项。然后对443个汉语方言的人称代词复数表示法进行归纳整理。现代汉语方言中使用的人称代词复数表示法共有4类24种复数表示法。用同样的方法来归纳44个少数民族语言,这些少数民族语言有3类9种... 本文首先确定人称代词复数表示法的类型参项。然后对443个汉语方言的人称代词复数表示法进行归纳整理。现代汉语方言中使用的人称代词复数表示法共有4类24种复数表示法。用同样的方法来归纳44个少数民族语言,这些少数民族语言有3类9种复数表示法,没有汉语方言复杂。接下来本文讨论了汉语人称代词复数表示法中的一些问题。首先讨论的是人称代词复数表示法的出现顺序与山东方言中的"回头演变"现象。然后本文从认知-功能语言学的角度来讨论四种人称代词复数表示法的优劣,认为信息结构和信息编码的优势是增标法成为汉语人称代词复数表示法优势类型的主要原因。最后的"余论"简略地讨论了语言类型学应如何处理汉语这种方言复杂的方言,语言类型学的发展趋势及其与方言学、历史语言学的关系等问题。 展开更多
关键词 现代汉语方言 人称代词复数表示法 同用型 换用 换标 复用 同字法 换字法 增标法 换标法
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Structural and biochemical insights into the homotypic PB1-PB1 complex between PKCζ and p62 被引量:2
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作者 REN Jun WANG Jue +1 位作者 WANG ZhiXin WU JiaWei 《Science China(Life Sciences)》 SCIE CAS 2014年第1期69-80,共12页
The atypical PKC isoforms (ζ and t) play essential roles in regulating various cellular processes. Both the hetero-interaction between PKCζand p62 through their N-terminal PB 1 domains and the homo-oligomerization... The atypical PKC isoforms (ζ and t) play essential roles in regulating various cellular processes. Both the hetero-interaction between PKCζand p62 through their N-terminal PB 1 domains and the homo-oligomerization of p62 via its PB 1 domain are critical for the activation of NF-r.B signaling; however, the molecular mechanisms concerning the formation and regulation of these homotypic complexes remain unclear. Here we determined the crystal structure of PKCζ-PB 1 in complex with a mono- meric p62-PB 1 mutant, where the massive electrostatic interactions between the acidic OPCA motif of PKCζ-PB 1 and the basic surface of p62-PB 1, as well as additional hydrogen bonds, ensure the formation of a stable and specific complex. The PKCζ-p62 interaction is interfered with the modification of a specific Cys of PKCζ by the antiarthritis drug aurothiomalate, though all four cysteine residues in the PKCζ-PB 1 domain can be modified in in vitro assay. In addition, detailed structural and biochemical analyses demonstrate that the PB 1 domains of aPKCs belong to the type I group, which can depolymerize the high-molecular-weight p62 aggregates into homo-oligomers of lower order. These data together unravel the molecular mecha- nisms of the homo- or hetero-interactions between p62 and PKCζ and provide the basis for designing inhibitors of NF-r,.B sig- naling. 展开更多
关键词 PKC P62 PB1 domain heterodimerization and homo-oligomerization aurothiomalate
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Characteristics of Fluid Flow and Heat Transfer in the Shell Side of the Trapezoidal-like Tilted Baffles Heat Exchanger 被引量:4
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作者 GU Xin ZHENG Zhiyang +3 位作者 XIONG Xiaochao WANG Tongtong LUO Yuankun WANG Ke 《Journal of Thermal Science》 SCIE EI CAS CSCD 2018年第6期602-610,共9页
Periodic whole cross-section computation models are established for segmental baffle heat exchanger, shutter baffle heat exchanger, and trapezoid-like tilted baffle heat exchanger. The reliability of models is verifie... Periodic whole cross-section computation models are established for segmental baffle heat exchanger, shutter baffle heat exchanger, and trapezoid-like tilted baffle heat exchanger. The reliability of models is verified by comparing the simulated results to the results obtained from the Bell-Delaware method. Due to the orthogonal assembly of the baffles, the shell side fluid shows the twisty flow of trapezoid-like tilted baffle heat exchanger. The essential mechanism on disturbing flow and heat transfer enhancement is revealed by defining the non-dimensional factor η of the shell side fluid flow direction of heat exchanger and the field synergy principle. The results show that at the same Reynolds number, the shell side fluid convection heat transfer coefficient of trapezoid-like tilted baffle heat exchanger is 12.43%-24.33% and 6.71%-11.51% higher than those of segmental baffle heat exchanger and shutter baffle heat exchanger, respectively. The shell side fluid flow velocity field and the pressure gradient field of trapezoid-like tilted baffle heat exchanger and shutter baffle heat exchanger decreases compared with that of segmental baffle heat exchanger, so the shell side fluid flow resistance and pressure drop is increased; the shell side comprehensive performance of trapezoid-like tilted baffle heat exchanger is 5.85%-9.06% higher than that of segmental baffle heat exchanger, and 15.27%-23.28% higher than that of shutter baffle heat exchanger. In this study, a baffle structure with higher efficiency of the energy utilization for the heat exchanger is provided. 展开更多
关键词 shell-and-tube heat exchanger trapezoid-like tilted baffle twisty flow field synergy principle
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Diagenetic fluid evolution and water-rock interaction model of carbonate cements in sandstone: An example from the reservoir sandstone of the Fourth Member of the Xujiahe Formation of the Xiaoquan-Fenggu area, Sichuan Province, China 被引量:16
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作者 LIU SiBing HUANG SiJing +2 位作者 SHEN ZhongMin Lü ZhengXiang SONG RongCai 《Science China Earth Sciences》 SCIE EI CAS 2014年第5期1077-1092,共16页
Carbonate cement is the most abundant cement type in the Fourth Member of the Xujiahe Formation in the Xiaoquan-Fenggu area of the West Sichuan Depression. Here we use a systematic analysis of carbonate cement petrolo... Carbonate cement is the most abundant cement type in the Fourth Member of the Xujiahe Formation in the Xiaoquan-Fenggu area of the West Sichuan Depression. Here we use a systematic analysis of carbonate cement petrology, mineralogy, carbon and oxygen isotope ratios and enclosure homogenization temperatures to study the precipitation mechanism, pore fluid evolu- tion, and distribution of different types of carbonate cement in reservoir sand in the study area. Crystalline calcite has relatively heavy carbon and oxygen isotope ratios (δ13C = 2.14%o, 8180 = -5.77‰), and was precipitated early. It was precipitated di- rectly from supersaturated alkaline fluid under normal temperature and pressure conditions. At the time of precipitation, the fluid oxygen isotope ratio was very light, mainly showing the characteristics of a mixed meteoric water-seawater fluid( δ180 = -3‰), which shows that the fluid during precipitation was influenced by both meteoric water and seawater. The calcite cement that fills in the secondary pores has relatively lighter carbon and oxygen isotope ratios (δ13C = -2.36%0, 8180 = -15.68‰). This cement was precipitated late, mainly during the Middle and Late Jurassic. An important material source for this carbonate cement was the feldspar corrosion process that involved organic matter. The Ca2+, Fe3+ and Mg2+ ions released by the clay mineral transformation process were also important source materials. Because of water-rock interactions during the buri- al process, the oxygen isotope ratio of the fluid significantly increased during precipitation, by about 3‰. The dolomite ce- ments in calcarenaceous sandstone that was precipitated during the Middle Jurassic have heavier carbon and oxygen isotope ratios, which are similar to those of carbonate debris in the sandstone (δ13C = 1.93%o, δ180 = -6.11‰), demonstrating that the two are from the same source that had a heavier oxygen isotope ratio (δ180 of about 2.2‰). The differences in fluid oxygen isotope ratios during cement precipitation reflect the influences of different water-rock interaction systems or different wa- ter-rock interaction strengths. This is the main reason why the sandstone containing many rigid particles (lithic quartz sand- stone) has a relatively negative carbon isotope ratio and why the precipitation fluid in calcarenaceous sandstone has a relatively heavier oxygen isotope ratio. 展开更多
关键词 carbonate cement carbon and oxygen isotope ratio fluid evolution water-rock interaction West Sichuan Depression
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Preference transfer model in collaborative filtering for implicit data
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作者 Bin JU Yun-tao QIAN Min-chao YE 《Frontiers of Information Technology & Electronic Engineering》 SCIE EI CSCD 2016年第6期489-500,共12页
Generally, predicting whether an item will be liked or disliked by active users, and how much an item will be liked, is a main task of collaborative filtering systems or recommender systems. Recently, predicting most ... Generally, predicting whether an item will be liked or disliked by active users, and how much an item will be liked, is a main task of collaborative filtering systems or recommender systems. Recently, predicting most likely bought items for a target user, which is a subproblem of the rank problem of collaborative filtering, became an important task in collaborative filtering. Traditionally, the prediction uses the user item co-occurrence data based on users' buying behaviors. However, it is challenging to achieve good prediction performance using traditional methods based on single domain information due to the extreme sparsity of the buying matrix. In this paper, we propose a novel method called the preference transfer model for effective cross-domain collaborative filtering. Based on the preference transfer model, a common basis item-factor matrix and different user-factor matrices are factorized.Each user-factor matrix can be viewed as user preference in terms of browsing behavior or buying behavior. Then,two factor-user matrices can be used to construct a so-called ‘preference dictionary' that can discover in advance the consistent preference of users, from their browsing behaviors to their buying behaviors. Experimental results demonstrate that the proposed preference transfer model outperforms the other methods on the Alibaba Tmall data set provided by the Alibaba Group. 展开更多
关键词 Recommender systems Collaborative filtering Preference transfer model Cross domain Implicit data
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Effect of time-odd fields on odd-even mass differences of semi-magic nuclei
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作者 Kun Yu XianRong Zhou +1 位作者 JiWei Cui H.Sagawa 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2016年第5期83-92,共10页
The effect of time-odd fields of Skyrme interaction on neutron odd-even mass differences is studied in the framework of axially deformed Skyrme Hartree-Fock(DSHF)+BCS model. To this end, we take into account both the ... The effect of time-odd fields of Skyrme interaction on neutron odd-even mass differences is studied in the framework of axially deformed Skyrme Hartree-Fock(DSHF)+BCS model. To this end, we take into account both the time-even and time-odd fields to calculate the one-neutron and two-neutron separation energies and pairing gaps of semi-magic Ca, Ni, and Sn isotopic chains. In the calculations, a surface-type pairing interaction(IS pairing) and an isospin dependent contact pairing interaction(IS+IV pairing)are adopted on top of Skyrme interactions SLy4, SLy6 and Sk M*, respectively. We find that the time-odd fields have in general small effects on pairing gaps, but achieve better agreement with experimental data using SLy4 and Sly6 interactions, respectively.It is also shown that the calculations with IS+IV pairing reproduce the one-neutron separation energies of Sn isotopes better than those with the IS pairing interaction when the contributions of the time-odd fields are included. 展开更多
关键词 odd-even staggering S1n S2n A3 and mean square deviations
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Synergistic Performance Management System and Its Associated Structural Model 被引量:3
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作者 Xiaoyong Luo Gang Du Rui Yan Fei Chen 《Journal of Systems Science and Information》 2009年第3期261-267,共7页
Aiming at the widespread issues of synergistic performance management, a conceptual model of synergistic performance management system is built. The order parameter of system synergy and the main factors, as well as t... Aiming at the widespread issues of synergistic performance management, a conceptual model of synergistic performance management system is built. The order parameter of system synergy and the main factors, as well as the degree of synergy and the concept of synergistic effect are proposed. An associated structural model of synergistic performance management system is established based on the method of structural equation modeling. 展开更多
关键词 SYNERGY performance management order parameter degree of synergy synergistic effect
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Structure Evolution in the Even-Even ^124-134Xe with IBM2
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作者 张大立 丁斌刚 《Communications in Theoretical Physics》 SCIE CAS CSCD 2013年第11期581-587,共7页
We have investigated the structure evolution of the ^124-134Xe isotopic chain in the framework of the proton-neutron interacting model IBM2. The positive parity spectra of the ground state, quasi-β and quasi-γ bands... We have investigated the structure evolution of the ^124-134Xe isotopic chain in the framework of the proton-neutron interacting model IBM2. The positive parity spectra of the ground state, quasi-β and quasi-γ bands are reproduced well. The staggering in ^124-130Xe are almost completely removed and the ? band agree well with the experiment data, even for the high-spin quasi-3 states. The key quantities of the collective structure evolution, including level energies, the B(E2) transition branching ratios, and the M1 excitations to 11^+ mixer-symmetry states are analyzed by comparing with the experimental data. The parameters for representation of the Oπν(6) and SUπν^*(3) features in isotopes are examined. Both experimental data and theoretical results show that the shape phase transition of ^124-134Xe isotopic chain is from the SUπν^* (3) (triaxial rotation) to the Uπν(5) (vibration motion) with a considerable constituent of the Oπν(6) symmetry (γ-unstable rotation), where the shape phase transition rapidly takes place between the neutron number N = 76 and N = 78. 展开更多
关键词 ^124-134Xe shape phase transition Uπν (5)-SUπν^* (3) transition IBM2
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