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The Positions and Number of Flux Loops and Magnetic Probes for the HT-7U Superconducting Tokamak
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作者 沈飙 罗家融 +1 位作者 万宝年 王华中 《Plasma Science and Technology》 SCIE EI CAS CSCD 2003年第3期1785-1794,共10页
The plasma shape and other paremeters such as /3P, li is important for the tokamak deveice where the plasma has a non-circular cross-section of sufficient elongation. The measuered signals of magnetic probes and flux ... The plasma shape and other paremeters such as /3P, li is important for the tokamak deveice where the plasma has a non-circular cross-section of sufficient elongation. The measuered signals of magnetic probes and flux loops are used to reconstruct the plasma shape and the current profile in device operation and plasma shape feed back control system. So the number and positions of magnetic probes and flux loops provides the basis of the plasma reconstruction. This paper instroduce how to use EFIT code (equilibrium fitting code) to determine the number and positions of the magnetic probes and flux loops. The simulation result is given also. 展开更多
关键词 equilibrium reconstruction EFIT code positions and number magnetic probes and flux loops
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On the Problem of All Equal Positive Odd Number Solutions of the Dissemination of the Ends' Guess 被引量:1
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作者 刘元宗 《Chinese Quarterly Journal of Mathematics》 CSCD 2000年第2期108-109,共2页
The thesis is concerned with the problem of the dissemination of the Ends’ guess and offers the formula of all equal positive odd number solutions.
关键词 Ends’ guess DISSEMINATION all equal positive odd number solutions
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Effect of the number of positive lymph nodes and lymph node ratio on prognosis of patients after resection of pancreatic adenocarcinoma 被引量:6
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作者 Zu-Qiang Liu Zhi-Wen Xiao +6 位作者 Guo-Pei Luo Liang Liu Chen Liu Jin Xu Jiang Long Quan-Xing Ni Xian-Jun Yu 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2014年第6期634-641,共8页
BACKGROUND: The prognostic factors related to lymph node involvement [lymph node status, the number of positive lymph nodes, lymph node ratio (LNR)] and the number of nodes evaluated in patients with pancreatic ade... BACKGROUND: The prognostic factors related to lymph node involvement [lymph node status, the number of positive lymph nodes, lymph node ratio (LNR)] and the number of nodes evaluated in patients with pancreatic adenocarcinoma after pancreatectomy are poorly defined. METHODS: A total of 167 patients who had undergone resection of pancreatic adenocarcinoma from February 2010 to August 2011 were included in this study. Histological examination was performed to evaluate the tumor differentiation and lymph node involvement. Univariate and multivariate analyses were made to determine the relationship between the variables related to nodal involvement and the number of nodes and survival. RESULTS: The median number of total nodes examined was 10 (range 0-44) for the entire cohort. The median number of total nodes examined in node-negative (pN0) patients was similar to that in node-positive (pN1) patients. Patients with pN1 diseases had significantly worse survival than those with pN0 ones (P=0.000). Patients with three or more positive nodes had a poorer prognosis compared with those with the negative nodes (P=0.000). The prognosis of the patients with negative nodes was similar to that of those with one to two positive nodes (P=0.114). The median survival of patients with an LNR ≥0.4 was shorter than that of patients with an LNR 〈0.4 in the pN1 cohort (P=0.014). No significance was found between the number of total nodes examined and the prognosis, regardless of the cutoff of 10 or 12 and in the entire cohort or the pN0 and pN1 groups. Based on the multivariate analysis of the entire cohort and the pN1 group, the nodal status, the number of positive nodes and the LNR were all associated with survival. CONCLUSIONS: In addition to the nodal status, the number of positive nodes and the LNR can serve as comprehensive factors for the evaluation of nodal involvement. This approach may be more effective for predicting the survival of patients with pancreatic adenocarcinoma after pancreatectomy. 展开更多
关键词 lymph node status lymph node ratio number of positive nodes number of total nodes examined pancreatic adenocarcinoma PANCREATECTOMY
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Gas Phase Thermodynamic Properties of Polychlorinated Xanthones Predicted with DFT Method and Cl Substituted Position 被引量:1
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作者 陈建挺 刘辉 +2 位作者 费艾莉 程维明 王遵尧 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2010年第3期462-471,共10页
The gas phase thermodynamic properties of 135 polychlorinated xanthones(PCXTs)are calculated using a combination of quantum mechanical computations performed with the Gaussian 03 program at the B3LYP/6-311G**level.It ... The gas phase thermodynamic properties of 135 polychlorinated xanthones(PCXTs)are calculated using a combination of quantum mechanical computations performed with the Gaussian 03 program at the B3LYP/6-311G**level.It is found that the chlorine substitution pattern strongly influences the thermodynamic properties of the compounds.The thermodynamic properties of congeners with the same number of chlorines also depend on the chlorine substitution pattern,especially for ortho-substituted congeners.PCXT congeners with one phenyl ring fully chlorinated are found to be the least stable among the analogues.The effect of the chlorine substitution pattern is quantitatively studied by considering the number and position of Cl atom substitution(NPCS).The results show that the NPCS model may be used to predict the thermodynamic properties for all 135 PCXT congeners. In addition,the values of molar heat capacities at constant pressure(cp,m)from 200 to 1000 K for PCXT congeners are calculated,and the temperature dependence relation of this parameter is obtained using the least-squares method. 展开更多
关键词 polychlorinated xanthones density functional theory number and position of Cl atom substitution thermodynamic property relative stability
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The Computing Formula of Number of Primes No More than Any Given Positive Integer
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作者 Maoze Wang Zhenxiang He Meiyi Wang 《Advances in Pure Mathematics》 2022年第3期229-247,共19页
In this paper, we give out the formula of number of primes no more than any given n (n ∈ Z<sup>+</sup>, n > 2). At the same time, we also show the principle, derivation process of the formula and appli... In this paper, we give out the formula of number of primes no more than any given n (n ∈ Z<sup>+</sup>, n > 2). At the same time, we also show the principle, derivation process of the formula and application examples, it is usually marked with π(n), which is: that is: where “[ ]” denotes taking integer. r = 1,2,3,4,5,6;s<sub>x</sub> = s<sub>1</sub>,s<sub>2</sub>,...,s<sub>j</sub>,s<sub>h</sub>;s1</sub>,s2</sub>,...,s<sub>j</sub>,,s<sub>h </sub><sub>= 0,1,2,3,....</sub>As i ≥ 2, 2 ≤ s<sub>x </sub>≤ i-1 (x=1,2,...,j,h). 展开更多
关键词 Positive Integer numbers Spectrum ROW Column Composition PRIME
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Reference satellite selection method for GNSS high-precision relative positioning
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作者 Xiao Gao Wujiao Dai +1 位作者 Zhiyong Song Changsheng Cai 《Geodesy and Geodynamics》 2017年第2期125-129,共5页
Selecting the optimal reference satellite is an important component of high-precision relat/ve positioning because the reference satellite directly influences the strength of the normal equation. The reference satelli... Selecting the optimal reference satellite is an important component of high-precision relat/ve positioning because the reference satellite directly influences the strength of the normal equation. The reference satellite selection methods based on elevation and positional dilution of precision (PDOP) value were compared. Results show that all the above methods cannot select the optimal reference satellite. We introduce condition number of the design matrix in the reference satellite selection method to improve structure of the normal equation, because condition number can indicate the ill condition of the normal equation. The experimental results show that the new method can improve positioning accuracy and reliability in precise relative positioning. 展开更多
关键词 Global Navigation Satellite System (GNSS)Relative positioning Reference satellite positional dilution of precision (PDOP)Condition number
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数控焊接变位机运动精度的影响因素 被引量:1
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作者 王政 乔及森 +1 位作者 樊丁 石玗 《焊接学报》 EI CAS CSCD 北大核心 2003年第3期61-64,共4页
通过试验测定和计算机软件对试验数据进行处理 ,研究了工作台在不同倾斜角时的回转角、载荷阻力矩、回转速度等单因素和多因素综合作用下 ,对数控座式焊接变位机工作台回转运动到位精度的影响。研究结果对设计、开发弧焊机器人用的数控... 通过试验测定和计算机软件对试验数据进行处理 ,研究了工作台在不同倾斜角时的回转角、载荷阻力矩、回转速度等单因素和多因素综合作用下 ,对数控座式焊接变位机工作台回转运动到位精度的影响。研究结果对设计、开发弧焊机器人用的数控焊件变位设备 。 展开更多
关键词 数控焊接变位机 弧焊机器人 到位偏差 运动精度 数控焊件变位设备
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Studies of Thermodynamic Properties and Relative Stability of Polybrominated Xanthones by Density Functional Theory 被引量:3
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作者 单刚 李秀菊 +1 位作者 王遵尧 杨郭英 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第2期225-232,共8页
The thermodynamic properties of xanthone(XTH) and 135 polybrominated xanthones(PBXTHs) in the standard state have been calculated at the B3LYP/6-31G* level using Gaussian 03 program.The isodesmic reactions were d... The thermodynamic properties of xanthone(XTH) and 135 polybrominated xanthones(PBXTHs) in the standard state have been calculated at the B3LYP/6-31G* level using Gaussian 03 program.The isodesmic reactions were designed to calculate the standard enthalpy of formation(△fHθ) and standard free energy of formation(△fGθ) of PBXTH congeners.The relations of these thermodynamic parameters with the number and position of Br atom substitution(NPBS) were discussed,and it was found that there exist high correlation between thermodynamic parameters(entropy(Sθ),△fHθ and △fGθ) and NPBS.According to the relative magnitude of their △fGθ,the relative stability order of PBXTH congeners was theoretically proposed.The relative rate constants of formation reactions of PBXTH congeners were calculated,Moreover,the values of molar heat capacity at constant pressure(Cp,m) from 200 to 1000 K for PBXTH congeners were also calculated,and the temperature dependence relation of them was obtained,suggesting very good relationships between Cp,m and temperature(T,T^1 and T^2) for almost all PBXTH congeners. 展开更多
关键词 polybrominated xanthone the number and position of Br atom substitution(NPBS) thermodynamic property relative stability molar heat capacity at constant pressure(Cp m)
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Studies of Structural and Thermodynamic Properties for Polychlorinated Thianthrenes by Density Functional Theory 被引量:1
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作者 刘辉 孙萍 +2 位作者 柳红霞 王遵尧 王连生 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第10期1255-1260,共6页
The structural and thermodynamic (PCTAs) in the ideal gas state at 298.15 K and 1.013 properties of 75 polychlorinated thianthrenes ×10^5 Pa have been calculated at the B3LYP/6- 31G* level using Gaussian 98 pr... The structural and thermodynamic (PCTAs) in the ideal gas state at 298.15 K and 1.013 properties of 75 polychlorinated thianthrenes ×10^5 Pa have been calculated at the B3LYP/6- 31G* level using Gaussian 98 program. Based on the output data of Gaussian, the isodesmic reactions were designed to calculate standard enthalpy of formation (△fH^θ) and standard free energy of formation (△fH^θ) of PCTAs congeners. The relations of these thermodynamic parameters with the number and position of C1 atom substitution (Npcs) were discussed, and it was found that there exists high correlation between thermodynamic parameters (total energy (TE), zero-point vibrational energy (ZPE), thermal correction to energy (Eth), heat capacity at constant volume (Cv^θ), entropy (S^θ), enthalpy (H^θ), free energy (G^θ), standard enthalpies of formation (△fH^θ) and standard Gibbs energies of formation (△fG^θ)) and Npcs. On the basis of the relative magnitude of their △fG^θ, the order of relative stability of PCTA congeners was theoretically proposed. In addition, the correlations between structural parameters and Npcs were also discussed. The good correlations were found between molecular average polarizability (α), energy of the highest occupied molecular orbital (EHOMO), molecular volume (Vm) and Npcs, and all R^2 values are larger than 0.95. Moreover, it was supposed that the isomer groups with higher toxicity should be Tri-CTA and TCTA. 展开更多
关键词 polychlorinated thianthrenes density functional theory (DFT) the number and position of CI atom substitution (Npcs) structural and thermodynamic parameters relative stability
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Characteristics of gravity signal and loading effect in China 被引量:1
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作者 Yi Shuang Sun Wenke 《Geodesy and Geodynamics》 2015年第4期280-285,共6页
The complex geographical environment in China makes its gravity signals miscellaneous.This work gives a comprehensive representation and explanation in secular trend of gravity change in different regions,the key feat... The complex geographical environment in China makes its gravity signals miscellaneous.This work gives a comprehensive representation and explanation in secular trend of gravity change in different regions,the key features of which include positive trend in inner Tibet Plateau and South China and negative trend in North China plain and high mountain Asia(HMA).We also present the patterns of amplitudes and phases of annual and semiannual change.The mechanism underlying the semiannual period is explicitly discussed.The displacement in three directions expressed in terms of geo-potential spherical coefficients and load Love numbers are given.A case study applied with these equations is presented.The results show that Global Positioning System(GPS) observations can be used to compare with Gravity Recovery and Climate Experiment(GRACE) derived displacement and the vertical direction has a signal-noise-ratio of about one order of magnitude larger than the horizontal directions. 展开更多
关键词 Gravity change Loading effect Gravity Recovery and Climate Experiment (GRACE)Load love number Global positioning System (GPS) Seasonal variation Gravity trend in China Comparison of GRACE and GPS
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DFT Study on Some Properties of Polybrominated Phenoxathiin 10-Oxides
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作者 曲瑞娟 石佳奇 +2 位作者 程润秋 杨曦 王遵尧 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2011年第10期1501-1508,共8页
With the B3LYP calculation method of density functional theory(DFT)and the 6-31G* basis set,full optimization calculation was made for phenoxathiin10-oxide(PTO)and 135 polybromine phenoxathiin 10-oxides(PBPTOs)... With the B3LYP calculation method of density functional theory(DFT)and the 6-31G* basis set,full optimization calculation was made for phenoxathiin10-oxide(PTO)and 135 polybromine phenoxathiin 10-oxides(PBPTOs)with the Gaussian 03 program and molar heat capacity in constant volume(CVθ)value of each molecule in the standard state was obtained.The relation between CVθ and the substitution position and number of bromine atom(NPBS)was studied,and the results indicated good correlation(R2 = 1.000)between CVθ and NPBS of PBPTO compounds.Based on the output file of Gaussian 03 program,molar heat capacity at constant pressure(Cp,m)of PBPTO compounds from 200 to 1,000 K was calculated with the statistical thermodynamics program,and the correlation equation between Cp,m and temperature(T,T-1 and T-2)was obtained with the least-squares method,and the correlation coefficient of the correlation equation(R2)was 1.000.In addition,based on the partition function of each molecule calculated by vibration analysis,the relative rate constant of formation of each molecule was calculated. 展开更多
关键词 PBPTOs substitution position and number of bromine atom(NPBS) molar heat capacity in constant volume(CVθ) molar heat capacity at constant pressure(Cp m) relative rate constant
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Theoretical Study on Thermodynamic Properties and Hydrophilicity of Polychorinated Phenothiazines (PCPTZs)
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作者 陈斌媛 张学胜 李定龙 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2011年第11期1575-1584,共10页
The thermodynamic properties of 135 polychlorinated phenothiazines (PCPTZs) in the standard state are calculated using a combination of quantum mechanical computations performed with the Gaussian 03 program at the B... The thermodynamic properties of 135 polychlorinated phenothiazines (PCPTZs) in the standard state are calculated using a combination of quantum mechanical computations performed with the Gaussian 03 program at the B3LYP/6-311G^** level, and their octanol-water partition coefficients (logKow) are calculated based on group contributions. The chlorine substitution pattern strongly influenced the thermodynamic properties and hydrophilicity of the compounds. The thermodynamic properties of congeners also depend on the chlorine substitution pattern. The effect of chlorine substitution pattern is quantitatively studied by considering the mmaber and position of Cl atom substitution (Npcs). The results show that the Npcs model may be used to predict the thermodynamic properties and hydrophilicity for all 135 PCPTZ congeners. 展开更多
关键词 polyehlorinated phenothiazines density functional theory (DFT) number and position of Cl atom substitution (Npcs) thermodynamic property HYDROPHILICITY
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Algebraic encoding scheme for aperture 3 hexagonal discrete global grid system 被引量:5
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作者 BEN Jin LI YaLu +2 位作者 ZHOU ChengHu WANG Rui DU LingYu 《Science China Earth Sciences》 SCIE EI CAS CSCD 2018年第2期215-227,共13页
Discrete Global Grid Systems(DGGSs) are spatial references that use a hierarchical tessellation of cells to partition and address the entire globe. They provide an organizational structure that permits fast integratio... Discrete Global Grid Systems(DGGSs) are spatial references that use a hierarchical tessellation of cells to partition and address the entire globe. They provide an organizational structure that permits fast integration between multiple sources of large and variable geospatial data sufficient for visualization and analysis. Despite a significant body of research supporting hexagonal DGGSs as the superior choice, the application thereof has been hindered owing in part to the lack of a rational hierarchy with an efficient addressing system. This paper presents an algebraic model of encoding scheme for the Aperture 3 Hexagonal(A3H) DGGS. Firstly, the definition of a grid cell, which is composed of vertices, edges, and a center, is introduced to describe fundamental elements of grids. Secondly, by identifying the grid cell with its center, this paper proves that cell centers at different levels can be represented exactly using a mixed positional number system in the complex plane through the recursive geometric relationship between two successive levels, which reveals that grid cells are essentially special complex radix numbers. Thirdly, it is shown that through the recursive geometric relationship of successive odd or even levels, the mixed positional number system can also be applied to uniquely represent cell centers at different levels under specific constraint conditions, according to which the encoding scheme is designed. Finally, it is shown that by extending the scheme to 20 triangular faces of the regular icosahedron,multi-resolution grids on closed surfaces of the icosahedron are addressed perfectly. Contrast experiments show that the proposed encoding scheme has the advantages of theoretical rigor and high programming efficiency and that the efficiency of cross-face adjacent cell searching is 242.9 times that of a similar scheme. Moreover, the proposed complex radix number representation is an ideal formalized description tool for grid systems. The research ideas introduced herein can be used to create a universal theoretical framework for DGGSs. 展开更多
关键词 Discrete Global Grid System HEXAGON positional number system Algebraic encoding
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