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Robotic natural orifice specimen extraction surgery I-type F method vs conventional robotic resection for lower rectal cancer 被引量:2
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作者 Fang Tao Dong-Ning Liu +4 位作者 Peng-Hui He Xin Luo Chi-Ying Xu Tai-Yuan Li Jin-Yuan Duan 《World Journal of Gastrointestinal Surgery》 SCIE 2023年第10期2142-2153,共12页
BACKGROUND Robotic resection using the natural orifice specimen extraction surgery I-type F method(R-NOSES I-F)is a novel minimally invasive surgical strategy for the treatment of lower rectal cancer.However,the curre... BACKGROUND Robotic resection using the natural orifice specimen extraction surgery I-type F method(R-NOSES I-F)is a novel minimally invasive surgical strategy for the treatment of lower rectal cancer.However,the current literature on this method is limited to case reports,and further investigation into its safety and feasibility is warranted.AIM To evaluate the safety and feasibility of R-NOSES I-F for the treatment of low rectal cancer.METHODS From September 2018 to February 2022,206 patients diagnosed with low rectal cancer at First Affiliated Hospital of Nanchang University were included in this retrospective analysis.Of these patients,22 underwent R-NOSES I-F surgery(RNOSES I-F group)and 76 underwent conventional robotic-assisted low rectal cancer resection(RLRC group).Clinicopathological data of all patients were collected and analyzed.Postoperative outcomes and prognoses were compared between the two groups.Statistical analysis was performed using SPSS software.RESULTS Patients in the R-NOSES I-F group had a significantly lower visual analog score for pain on postoperative day 1(1.7±0.7 vs 2.2±0.6,P=0.003)and shorter postoperative anal venting time(2.7±0.6 vs 3.5±0.7,P<0.001)than those in the RLRC group.There were no significant differences between the two groups in terms of sex,age,body mass index,tumor size,TNM stage,operative time,intrao-perative bleeding,postoperative complications,or inflammatory response(P>0.05).Postoperative anal and urinary functions,as assessed by Wexner,low anterior resection syndrome,and International Prostate Symptom Scale scores,were similar in both groups(P>0.05).Long-term follow-up revealed no significant differences in the rates of local recurrence and distant metastasis between the two groups(P>0.05).CONCLUSION R-NOSES I-F is a safe and effective minimally invasive procedure for the treatment of lower rectal cancer.It improves pain relief,promotes gastrointestinal function recovery,and helps avoid incision-related complications. 展开更多
关键词 Robotic surgery Natural orifice specimen extraction surgery Lower rectal cancer Robotic resection using the natural orifice specimen extraction surgery I-type f method
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CF_(3)SO_(2)F/N_(2)混合气体的电离特性试验研究 被引量:1
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作者 向志辉 郑宇 +2 位作者 任书波 周文俊 朱太云 《高电压技术》 EI CAS CSCD 北大核心 2024年第3期1331-1339,共9页
为评估CF_(3)SO_(2)F/N_(2)混合气体的绝缘性能,研究了其在电场中的电离特性。通过稳态汤逊实验(SST)测量获得了CF3SO2F摩尔分数分别为10%、20%、30%、40%、100%的CF_(3)SO_(2)F/N_(2)混合气体的有效电离系数和临界约化场强,研究了混合... 为评估CF_(3)SO_(2)F/N_(2)混合气体的绝缘性能,研究了其在电场中的电离特性。通过稳态汤逊实验(SST)测量获得了CF3SO2F摩尔分数分别为10%、20%、30%、40%、100%的CF_(3)SO_(2)F/N_(2)混合气体的有效电离系数和临界约化场强,研究了混合比例、约化场强和电极距离对其电离特性的影响,并比较了CF_(3)SO_(2)F/N_(2)混合气体相对于SF6的绝缘强度。结果表明:CF_(3)SO_(2)F摩尔分数为10%时,CF_(3)SO_(2)F/N_(2)混合气体的电离特性与N_(2)类似;随着CF_(3)SO_(2)F占比增大至20%以上后,CF3SO2F/N2混合气体的电离特性逐步由CF_(3)SO_(2)F主导;CF_(3)SO_(2)F/N_(2)混合气体相对于SF6的理论绝缘强度随着CF_(3)SO_(2)F摩尔分数的增大而增大,40%CF_(3)SO_(2)F/60%N_(2)混合气体的临界约化场强约为SF_(6)的1.01倍,但其对电场变化的敏感程度不如SF6。研究结果可为CF_(3)SO_(2)F/N_(2)混合气体的绝缘强度评估提供理论基础。 展开更多
关键词 Cf_(3)SO_(2)f/N_(2)混合气体 Sf_(6)替代气体 稳态汤逊实验 临界约化场强 有效电离系数
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Al_(2)O_(3)f/Al_(2)O_(3)陶瓷基复合材料研究进展
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作者 莫琛 向阳 +4 位作者 陈坤 张稳 彭志航 文瑾 曹建辉 《材料导报》 EI CAS CSCD 北大核心 2024年第18期1-9,共9页
目前,航空发动机等高温部件对热结构材料性能要求日渐严苛。Al_(2)O_(3)f/Al_(2)O_(3)陶瓷基复合材料(Al_(2)O_(3)f/Al_(2)O_(3)CMCs)因具有优异的力学性能和抗氧化性,成为了热结构材料体系的研究热点。本文综述了Al_(2)O_(3)f/Al_(2)O_... 目前,航空发动机等高温部件对热结构材料性能要求日渐严苛。Al_(2)O_(3)f/Al_(2)O_(3)陶瓷基复合材料(Al_(2)O_(3)f/Al_(2)O_(3)CMCs)因具有优异的力学性能和抗氧化性,成为了热结构材料体系的研究热点。本文综述了Al_(2)O_(3)f/Al_(2)O_(3)CMCs的组成体系、主要性能和制备方法,并分析了该材料在相关领域的应用以及未来的发展趋势。 展开更多
关键词 Al_(2)O_(3)f /Al_(2)O_(3) CMCs 组成体系 抗氧化 制备方法 发展趋势
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Bi掺杂Na_(3)V_(2)(PO_(4))_(2)F正极材料的制备及电化学性能
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作者 陈仟惠 卢秋影 +4 位作者 李仁才 欧盈君 黄蔚欣 李华锋 龚福忠 《化工技术与开发》 CAS 2024年第9期37-41,共5页
本文引入离子半径较大的Bi^(3+)作为Na_(3)V_(2)(PO_(4))_(2)F_(3)中V位的掺杂物,同时协同碳包覆的改性作用,采用溶胶-凝胶法合成了Na_(3)V_(1.95)Bi_(0.05)(PO_(4))_(2)F_(3)/C聚阴离子型正极材料。电化学测量结果表明,在电压范围为2.3... 本文引入离子半径较大的Bi^(3+)作为Na_(3)V_(2)(PO_(4))_(2)F_(3)中V位的掺杂物,同时协同碳包覆的改性作用,采用溶胶-凝胶法合成了Na_(3)V_(1.95)Bi_(0.05)(PO_(4))_(2)F_(3)/C聚阴离子型正极材料。电化学测量结果表明,在电压范围为2.3~4.3V、电流密度为0.1A·g^(-1)的条件下充放电时,Na_(3)V_(1.95)Bi_(0.05)(PO_(4))_(2)F_(3)/C材料的初始充/放电比容量为107.4/102.3 mAh·g^(-1),初始库伦效率为95%。在0.1、0.2、0.5、1.0、0.1 A·g^(-1)的电流密度下进行交替循环充放电时,材料的放电比容量分别为102.3、96.0、91.4、85.6、96.5 mAh·g^(-1),表现出良好的倍率性能。与未掺杂的Na_(3)V_(2)(PO_(4))_(2)F_(3)相比,Na_(3)V_(1.95)Bi_(0.05)(PO_(4))_(2)F_(3)/C的比容量提高了约20%。 展开更多
关键词 氟磷酸钒钠 铋掺杂 溶胶-凝胶法 正极材料 比容量
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一种有效的适合F-J方法从背景噪声资料中提取多阶频散曲线的台阵划分方法
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作者 袁艺 陈晓非 《地球物理学报》 SCIE EI CAS CSCD 北大核心 2024年第2期492-502,共11页
近年发展起来的从地震背景噪声提取多阶频散曲线的F-J方法是一种台阵分析方法,对某一特定的研究区域内台阵的划分方式直接影响成像的效果.当研究区域地下结构较简单,且台站间距比较均匀时,可以使用简单的平移式移动阵列法;然而若研究区... 近年发展起来的从地震背景噪声提取多阶频散曲线的F-J方法是一种台阵分析方法,对某一特定的研究区域内台阵的划分方式直接影响成像的效果.当研究区域地下结构较简单,且台站间距比较均匀时,可以使用简单的平移式移动阵列法;然而若研究区域地下结构复杂多变,尤其是台站间距疏密不均时,就需要根据具体的地域特征灵活划分台阵.本文介绍了一种适用于地下结构复杂及台站间距不均匀区域的台阵划分方法,具有一定的普适性.我们将其应用于美国阿拉斯加及加拿大西北部,验证了相比于简单的沿经纬度移动阵列,我们的分区方法确实大大提高了结果的分辨率,为后续反演研究区域三维速度结构提供了坚实的保障. 展开更多
关键词 f-J变换 台阵划分方法 多阶面波 阿拉斯加
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F掺杂SrTiO_(3)的制备及光电化学阴极保护性能研究
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作者 王建省 孔存辉 +1 位作者 曾雄丰 赵英娜 《人工晶体学报》 CAS 北大核心 2024年第4期707-713,共7页
SrTiO_(3)因合适的能带结构和稳定的物化特性,在光电化学阴极保护领域有很大的应用潜力,但是对太阳光的利用率低和光生电子-空穴对复合率高等问题限制了其进一步发展。基于此,利用阴离子(F)掺杂对SrTiO_(3)改性,以得到高效、稳定光电转... SrTiO_(3)因合适的能带结构和稳定的物化特性,在光电化学阴极保护领域有很大的应用潜力,但是对太阳光的利用率低和光生电子-空穴对复合率高等问题限制了其进一步发展。基于此,利用阴离子(F)掺杂对SrTiO_(3)改性,以得到高效、稳定光电转换性能的SrTiO_(3)光阳极材料。通过溶剂热法制备了不同F掺杂浓度的SrTiO_(3)光阳极材料,UV-Vis DRS和PL测试结果表明,F掺杂提高了SrTiO_(3)对太阳光的利用率和光生电子-空穴对的分离能力。光电化学阴极保护测试结果表明:光照条件下,当F掺杂量为2.0%(原子数分数)时,F-2.0%-SrTiO_(3)与304不锈钢偶联后其光电流密度达到3.7μA/cm^(2),使304不锈钢的开路电位负移至-0.42 V,在模拟海水中为304不锈钢提供有效保护。 展开更多
关键词 SrTiO_(3) f掺杂 溶剂热法 光电化学阴极保护 光学性质
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一类具有C-F边界的旋转薄壁梁振动方程整体解的存在性
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作者 沈林 胡淑珂 《河南科技学院学报(自然科学版)》 2024年第4期47-55,共9页
航空发动机作为大型飞机的心脏,为大型飞机提供动力,是航空工业发展的重要支柱.同时,航空发动机的制造水平也是每个国家国力、科技和工业基础的重要体现.航空发动机零部件中最多也最重要的当属发动机叶片,其重要性主要体现在高速旋转时... 航空发动机作为大型飞机的心脏,为大型飞机提供动力,是航空工业发展的重要支柱.同时,航空发动机的制造水平也是每个国家国力、科技和工业基础的重要体现.航空发动机零部件中最多也最重要的当属发动机叶片,其重要性主要体现在高速旋转时转子叶片发生的振动故障.为了研究高速旋转时转子叶片发生的振动,在C-F边界条件下考虑了一类圆截面旋转薄壁梁振动方程,其中C-F边界为常见的叶片左端固定(clamped boundary)、右端自由振动边界(free boundary).首先,将振动方程组简化为向量方程,并给出向量方程弱解的定义;其次,借助Faedo-Galerkin方法构造了振动方程的近似解,并利用常微分方程解的存在性理论证明了近似解存在的唯一性;最后,利用能量方法和Gronwall不等式得到了近似解的一致估计,进而得到了方程整体弱解存在的唯一性.利用Gagliardo-Nirenberg不等式、Young不等式和Holder不等式得到了整体弱解的高阶估计,进而证明了整体强解的存在性. 展开更多
关键词 旋转薄壁梁 转子叶片 C-f边界 强解 能量方法
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变系数F展开法求解非线性Schrodinger方程的精确解 被引量:1
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作者 曹娜 徐丽阳 尹晓军 《应用数学》 北大核心 2023年第1期161-169,共9页
本文基于变系数F展开法,并借助Mathematica数学软件,求解了水平科氏力作用下Rossby波振幅满足的非线性Schrodinger方程,得到一系列Jacobi椭圆函数解,以及当模数m→1和m→0时由其退化的双曲函数解和三角函数解,并绘制它们的三维图形.扩... 本文基于变系数F展开法,并借助Mathematica数学软件,求解了水平科氏力作用下Rossby波振幅满足的非线性Schrodinger方程,得到一系列Jacobi椭圆函数解,以及当模数m→1和m→0时由其退化的双曲函数解和三角函数解,并绘制它们的三维图形.扩展了变系数F展开法求解非线性偏微分方程的应用范畴.同时也为非线性Schr?dinger方程得到更多形式的精确解. 展开更多
关键词 变系数f展开法 非线性SCHRODINGER方程 JACOBI椭圆函数解
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肖邦《f小调幻想曲》Op.49的创作特点与演奏方法 被引量:1
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作者 崔秀峰 《齐齐哈尔大学学报(哲学社会科学版)》 2023年第8期133-137,共5页
肖邦所创作的第四十九号作品《f小调幻想曲》正是其代表作品之一,该首钢琴曲被创作于1840年到1841年之间,通过采用变奏曲式、回旋曲式以及变奏曲式混合曲式结构,利用引子、呈示部、发展部、中段、再现部、尾声等六个部分,更真实、有效... 肖邦所创作的第四十九号作品《f小调幻想曲》正是其代表作品之一,该首钢琴曲被创作于1840年到1841年之间,通过采用变奏曲式、回旋曲式以及变奏曲式混合曲式结构,利用引子、呈示部、发展部、中段、再现部、尾声等六个部分,更真实、有效的呈现出浪漫主义钢琴曲,因而《f小调幻想曲》也被视为浪漫主义时期音乐作品的代表,Op.49对学习钢琴曲创作结构、了解浪漫时期钢琴音乐特点都有积极的影响。 展开更多
关键词 f小调幻想曲》 创作特点 演奏方法
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积分映射法I/F转换电路的设计与实现
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作者 冯济琴 邹劲松 +3 位作者 陈程 朱青松 刘杰 白仲熠 《重庆理工大学学报(自然科学)》 北大核心 2023年第11期326-332,共7页
针对传统I/F转换电路逻辑复杂、器件性能要求高的情况,设计了一种基于积分映射法的I/F转换电路。将第一级积分电压输入映射电路,积分电压映射到控制芯片TTL标准内,使控制芯片同时实现电压比较、逻辑控制两种功能,取代传统I/F转换电路专... 针对传统I/F转换电路逻辑复杂、器件性能要求高的情况,设计了一种基于积分映射法的I/F转换电路。将第一级积分电压输入映射电路,积分电压映射到控制芯片TTL标准内,使控制芯片同时实现电压比较、逻辑控制两种功能,取代传统I/F转换电路专用比较和逻辑控制2个分立模块。通过Multism建立仿真模型,验证了所设计电路的功能特性。在常温条件进行电路测试,实验结果表明:所设计的I/F转换电路零位稳定性优于2.14366×10^(-6),线性度达到10个ppm内。 展开更多
关键词 I/f转换 恒流源 推挽电路 积分映射法
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Improvement of the minimal residual method for solving nonsymmetric linear systems 被引量:1
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作者 张居丽 蒋尔雄 《Journal of Shanghai University(English Edition)》 CAS 2007年第4期332-335,共4页
In this paper, the minimal residual (MRES) method for solving nonsymmetric equation systems was improved, the recurrence relation was deduced between the approximate solutions of the linear equation system Ax = b, a... In this paper, the minimal residual (MRES) method for solving nonsymmetric equation systems was improved, the recurrence relation was deduced between the approximate solutions of the linear equation system Ax = b, and a more effective method was presented, which can reduce the operational count and the storage. 展开更多
关键词 nonsymmetric matrix minimal residual (MRES) method the recurrence relation between approximate solutions.2000 Mathematics Subject Classification 65f10
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Applications of F-expansion method to the coupled KdV system 被引量:2
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作者 李保安 王明亮 《Chinese Physics B》 SCIE EI CAS CSCD 2005年第9期1698-1706,共9页
An extended F-expansion method for finding periodic wave solutions of nonlinear evolution equations in mathematical physics is presented, which can be thought of as a concentration of extended Jacobi elliptic function... An extended F-expansion method for finding periodic wave solutions of nonlinear evolution equations in mathematical physics is presented, which can be thought of as a concentration of extended Jacobi elliptic function expansion method proposed more recently. By using the homogeneous balance principle and the extended F-expansion, more periodic wave solutions expressed by Jacobi elliptic functions for the coupled KdV equations are derived. In the limit cases, the solitary wave solutions and the other type of travelling wave solutions for the system are also obtained. 展开更多
关键词 coupled KdV equations extended f-expansion method Jacobi elliptic functions periodic wave solutions solitary wave solutions
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The Influence of Initial Carbonate Concentration on the Folin-Ciocalteu Micro-Method for the Determination of Phenolics with Low Concentration in the Presence of Me-thanol: A Comparative Study of Real-Time Monitored Reactions 被引量:1
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作者 Nunzia Cicco Vincenzo Lattanzio 《American Journal of Analytical Chemistry》 2011年第7期840-848,共9页
During the Folin Ciocalteu (F-C) micro-assay for the determination of phenolics in the presence of methanol, fine solids can form. In a previous paper, we hypothesized that the interference from alcohol on the F-C rea... During the Folin Ciocalteu (F-C) micro-assay for the determination of phenolics in the presence of methanol, fine solids can form. In a previous paper, we hypothesized that the interference from alcohol on the F-C reaction can be minimized depending on the particular procedure used to reach the alkalinity condition. In order to demonstrate our hypothesis we studied, by spectrophotometrically monitoring, the time-behaviour of the reactions carried out in the presence of different methanol concentrations at the same alkalinity condition from two protocols. The results showed that the interfering effect of methanol on the F-C micro-method can be affect and even prevented depending on working conditions. In particular, the formation of fine solids can be delayed, slowed down and prevented depending on the initial carbonate concentration used. We have explained why the initial carbonate concentration, used to reach the final alkalinity condition, plays an important role in the F-C reaction carried out in the presence of methanol. Moreover, the results from real-time monitoring showed that, differently from traditional F-C procedure, our procedure allows us to carry out the F-C micro method in the presence of 6% methanol, as an extreme concentration, reading the absorbance at real time 24 min. The real-time monitoring of absorbance can be considered as a useful means to explore the effect of other parameters on precipitate formation caused by the presence of methanol in the F-C reaction. 展开更多
关键词 f-C Micro-method Phenolics CARBONATE Influence METHANOL Effect
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Extended (G'/G) Method Applied to the Modified Non-Linear Schrodinger Equation in the Case of Ocean Rogue Waves
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作者 Atock A. Nwatchok Stéphane Daika Augustin Mbane Biouélé César 《Open Journal of Marine Science》 2014年第4期246-256,共11页
The existence of rogue (or freak) waves is now universally recognized and material proofs on the extent of damage caused by these ocean’s phenomena are available. Marine observations as well as laboratory experiments... The existence of rogue (or freak) waves is now universally recognized and material proofs on the extent of damage caused by these ocean’s phenomena are available. Marine observations as well as laboratory experiments show exactly that rogue waves occur in deep and shallow water. To study the behavior of freak waves in terms of their space and time evolution, that is, their motion and also in terms of mechanical transformations that these systems may suffer in their dealings with other systems, we derive a modified nonlinear Schr&oumldinger equation modeling the propagation of rogue waves in deep water in order to seek analytic solutions of this nonlinear partial differential equation by using generalized extended G'/G-expansion method with the aid of mathematica. Particular attentions have been paid to the behavior of rogue wave’s amplitude which highlights rogue wave’s destructive power. 展开更多
关键词 Deep Water Generalized EXTENDED G'/g-expansion method Rogue WAVES
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Exact solutions for the coupled Klein-Gordon-Schrǒdinger equations using the extended F-expansion method 被引量:1
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作者 何红生 陈江 杨孔庆 《Chinese Physics B》 SCIE EI CAS CSCD 2005年第10期1926-1931,共6页
The extended F-expansion method or mapping method is used to construct exact solutions for the coupled KleinGordon Schr/Sdinger equations (K-G-S equations) by the aid of the symbolic computation system Mathematica. ... The extended F-expansion method or mapping method is used to construct exact solutions for the coupled KleinGordon Schr/Sdinger equations (K-G-S equations) by the aid of the symbolic computation system Mathematica. More solutions in the Jacobi elliptic function form are obtained, including the single Jacobi elliptic function solutions, combined Jacobi elliptic function solutions, rational solutions, triangular solutions, soliton solutions and combined soliton solutions. 展开更多
关键词 extended f-expansion method exact solutions coupled K-G-S equations Jacobi elliptic function
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基于F⁃J法微动探测的表层结构调查 被引量:1
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作者 赵容容 杨振涛 +3 位作者 任承豪 周鑫 王轶 陈伟 《石油地球物理勘探》 EI CSCD 北大核心 2023年第4期789-800,共12页
三维地震勘探常常处于城镇、道路等无法实施微测井等静校正方法的区域,近期人们尝试利用微动调查替代现有的静校正方法,取得了一定效果。现今微动调查在石油勘探的应用中主要通过提取面波频散曲线反演地层速度结构。该方法在石油勘探领... 三维地震勘探常常处于城镇、道路等无法实施微测井等静校正方法的区域,近期人们尝试利用微动调查替代现有的静校正方法,取得了一定效果。现今微动调查在石油勘探的应用中主要通过提取面波频散曲线反演地层速度结构。该方法在石油勘探领域仍处于起步阶段,作为核心技术的频散成像方法种类繁多,其中2019年提出的频率—贝塞尔变换法(Frequency‑Bessel,F‑J)受到人们的广泛关注。相比空间自相关方法(SPAC),F‑J方法在利用背景噪声高阶模式面波成像上具有巨大优势。为了更好地研究F‑J方法的适用性,首先利用合成数据分析了不同观测系统和采集参数对F‑J成像的影响;然后利用四川某地实际噪声数据分析了不同观测系统、采集时间对F‑J频散成像的影响。实际应用中采用分段择优叠加得到的频散谱,可有效提高频散谱成像质量,为准确提取频散曲线提供了数据基础。进一步对比测井数据,发现利用基阶、高阶模式频散曲线进行多模式联合反演可精确地反演地层结构,使经济、高效地获得表层结构成为可能。 展开更多
关键词 微动 瑞雷波 高阶面波 基阶面波 频率—贝塞尔变换(f‑J) 空间自相关(SPAC)
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Comparison between methods for predicting maximum solid solubility of transition metals in solvent metal 被引量:1
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作者 周自强 方守狮 冯锋 《中国有色金属学会会刊:英文版》 CSCD 2003年第5期1185-1189,共5页
It is important to know the maximum solid solubility( C max ) of various transition metals in a metal when one designs multi component alloys. There have been several semi empirical approaches to qualitatively predict... It is important to know the maximum solid solubility( C max ) of various transition metals in a metal when one designs multi component alloys. There have been several semi empirical approaches to qualitatively predict the C max , such as Darken Gurry(D G) theorem, Miedema Chelikowsky(M C) theorem, electron concentration rule and the bond parameter rule. However, they are not particularly valid for the prediction of C max . It was developed on the basis of energetics of alloys as a new method to predict C max of different transition metals in metal Ti, which can be described as a semi empirical equation using the atomic parameters, i e, electronegativity difference, atomic diameter and electron concentration. It shows that the present method can be used to explain and deduce D G theorem, M C theorem and electron concentration rule. 展开更多
关键词 最大固溶度 金属溶解 原子大小系数 电子浓度 负电性区分
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A STUDY OF THE XBS^+CATIONS(X=H,F,Cl)BY IMPROVED MS-X_α METHOD
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作者 Han Xing LIU Advanced Materials Research Institute,Wuhan University of Technology,Wuhan,430070 Chia Chung SUN Institute of Theoretical Chemistry,Jilin University,Changchun,130023 《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第1期59-62,共4页
By means of improved overlapping Muffin-Tin X_a method recently developed the ground state ~2and the first excited state ~2Σ^+ of the XBS^+(X=H,F,Cl)cations are studied.The calculated energies are in good agreement w... By means of improved overlapping Muffin-Tin X_a method recently developed the ground state ~2and the first excited state ~2Σ^+ of the XBS^+(X=H,F,Cl)cations are studied.The calculated energies are in good agreement with experiment.The ionization potentials of sulphi- doborons,XBS(X=H,F,Cl,Br)are also computed and compared with photoelectron spectra re- sults. 展开更多
关键词 X=H f Cl)BY IMPROVED MS-X CATIONS method X A STUDY Of THE XBS MS CL
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A new measuring method for maximal length, width and thickness dimensions of coarse aggregates
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作者 段跃华 张肖宁 吴传海 《Journal of Central South University》 SCIE EI CAS 2011年第6期2150-2156,共7页
In order to establish a new method for measuring the dimensions of coarse aggregates, five different-size flat and elongated (F&E) coarse aggregates were glued into two specimens by epoxy resin, respectively, and ... In order to establish a new method for measuring the dimensions of coarse aggregates, five different-size flat and elongated (F&E) coarse aggregates were glued into two specimens by epoxy resin, respectively, and slice images were obtained by X-ray CT, then the aggregates were extracted by the fuzzy c-means clustering algorithm. Attributions of the particle on different cross-sections were determined by the ‘overlap area method’. And unified three-dimensional Cartesian coordinate system was established based on continuous slice images. The coefficient values of spherical harmonics descriptor representing particles surface profile were gained, then each scanned particle was represented by 60×120 discrete points conformably with spherical harmonics descriptor. The chord length and direction angles were determined by the calculation. With the major axis (L) and orthogonal axis (W and T), the calculated results were compared with those measured by caliper. It is concluded that the new L, W, and T dimension measuring method is able to take the place of the present manual measurement. 展开更多
关键词 coarse aggregate flat and elongated f&E) aggregate X-ray CT digital image processing fuzzy c-means clustering overlap area method spherical harmonics
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Classifying Heart Disease in Medical Data Using Deep Learning Methods
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作者 T. Velmurugan U. Latha 《Journal of Computer and Communications》 2021年第1期66-79,共14页
<div style="text-align:justify;"> Recent days, heart ailments assume a fundamental role in the world. The physician gives different name for heart disease, for example, cardiovascular failure, heart fa... <div style="text-align:justify;"> Recent days, heart ailments assume a fundamental role in the world. The physician gives different name for heart disease, for example, cardiovascular failure, heart failure and so on. Among the automated techniques to discover the coronary illness, this research work uses Named Entity Recognition (NER) algorithm to discover the equivalent words for the coronary illness content to mine the significance in clinical reports and different applications. The Heart sickness text information given by the physician is taken for the preprocessing and changes the text information to the ideal meaning, at that point the resultant text data taken as input for the prediction of heart disease. This experimental work utilizes the NER to discover the equivalent words of the coronary illness text data and currently uses the two strategies namely Optimal Deep Learning and Whale Optimization which are consolidated and proposed another strategy Optimal Deep Neural Network (ODNN) for predicting the illness. For the prediction, weights and ranges of the patient affected information by means of chosen attributes are picked for the experiment. The outcome is then characterized with the Deep Neural Network and Artificial Neural Network to discover the accuracy of the algorithms. The performance of the ODNN is assessed by means for classification methods, for example, precision, recall and f-measure values. </div> 展开更多
关键词 Named Entity Recognition Algorithm Neural Network methods Whale Optimization Algorithm f-MEASURE RECALL PRECISION
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