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Evolution of nonmetallic inclusions in 80-t 9CrMoCoB large-scale ingots during electroslag remelting process
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作者 Shengchao Duan Min Joo Lee +3 位作者 Yao Su Wangzhong Mu Dong Soo Kim Joo Hyun Park 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第7期1525-1539,共15页
In combination with theoretical calculations,experiments were conducted to investigate the evolution behavior of nonmetallic inclusions(NMIs)during the manufacture of large-scale heat-resistant steel ingots using 9CrM... In combination with theoretical calculations,experiments were conducted to investigate the evolution behavior of nonmetallic inclusions(NMIs)during the manufacture of large-scale heat-resistant steel ingots using 9CrMoCoB heat-resistant steel and CaF_(2)–CaO–Al_(2)O_(3)–SiO_(2)–B_(2)O_(3)electroslag remelting(ESR)-type slag in an 80-t industrial ESR furnace.The main types of NMI in the consumable electrode comprised pure alumina,a multiphase oxide consisting of an Al_(2)O_(3)core and liquid CaO–Al_(2)O_(3)–SiO_(2)–MnO shell,and M_(23)C_(6)carbides with an MnS core.The Al_(2)O_(3)and MnS inclusions had higher precipitation temperatures than the M_(23)C_(6)-type carbide under equilibrium and nonequilibrium solidification processes.Therefore,inclusions can act as nucleation sites for carbide layer precipitation.The ESR process completely removed the liquid CaO–Al_(2)O_(3)–SiO_(2)–MnO oxide and MnS inclusion with a carbide shell,and only the Al_(2)O_(3)inclusions and Al_(2)O_(3)core with a carbide shell occupied the remelted ingot.The M_(23)C_(6)-type carbides in steel were determined as Cr_(23)C_(6)based on the analysis of transmission electron microscopy results.The substitution of Cr with W,Fe,or/and Mo in the Cr_(23)C_(6)lattice caused slight changes in the lattice parameter of the Cr_(23)C_(6)carbide.Therefore,Cr_(21.34)Fe_(1.66)C_(6),(Cr_(19)W_(4)C_(6),Cr_(18.4)Mo_(4.6)C_(6),and Cr_(16)Fe_(5)Mo_(2)C_(6)can match the fraction pattern of Cr_(23)C_(6)carbide.The Al_(2)O_(3)inclusions in the remelted ingot formed due to the reduction of CaO,SiO_(2),and MnO components in the liquid inclusion.The increased Al content in liquid steel or the higher supersaturation degree of Al_(2)O_(3)precipitation in the remelted ingot than that in the electrode can be attributed to the evaporation of CaF_(2)and the increase in CaO content in the ESR-type slag. 展开更多
关键词 nonmetallic inclusion heat-resistant steel electroslag remelting M_(23)C_(6) carbide MnS inclusion supersaturation degree
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The Effects of Thermal Radiation and Viscous Dissipation on the Stagnation Point Flow of a Micropolar Fluid over a Permeable Stretching Sheet in the Presence of Porous Dissipation 被引量:1
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作者 Muhammad Salman Kausar H.A.M.Al-Sharifi +1 位作者 Abid Hussanan Mustafa Mamat 《Fluid Dynamics & Materials Processing》 EI 2023年第1期61-81,共21页
In this paper,the effects of thermal radiation and viscous dissipation on the stagnation–point flow of a micropolar fluid over a permeable stretching sheet with suction and injection are analyzed and discussed.A suit... In this paper,the effects of thermal radiation and viscous dissipation on the stagnation–point flow of a micropolar fluid over a permeable stretching sheet with suction and injection are analyzed and discussed.A suitable similarity transformation is used to convert the governing nonlinear partial differential equations into a system of nonlinear ordinary differential equations,which are then solved numerically by a fourth–order Runge–Kutta method.It is found that the linear fluid velocity decreases with the enhancement of the porosity,boundary,and suction parameters.Conversely,it increases with the micropolar and injection parameters.The angular velocity grows with the boundary,porosity,and suction parameters,whereas it is reduced if the micropolar and injection parameters become larger.It is concluded that the thermal boundary layer extension increases with the injection parameter and decreases with the suction parameter. 展开更多
关键词 Micropolar fluid viscous dissipation stagnation point stretching sheet porous media thermal radiation
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Nanoparticle Shape Effect on a Sodium–Alginate Based Cu–Nanofluid under a Transverse Magnetic Field 被引量:1
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作者 Samia Rani H.A.M.Al–Sharifi +2 位作者 Mohammad S.Zannon Abid Hussanan Zafar Ullah 《Fluid Dynamics & Materials Processing》 EI 2023年第7期1875-1896,共22页
Sodium-alginate(SA)based nanofluids represent a new generation of fluids with improved performances in terms of heat transfer.This work examines the influence of the nanoparticle shape on a non–Newtonian viscoplastic... Sodium-alginate(SA)based nanofluids represent a new generation of fluids with improved performances in terms of heat transfer.This work examines the influence of the nanoparticle shape on a non–Newtonian viscoplastic Cu–nanofluid pertaining to this category.In particular,a stretching/shrinking sheet subjected to a transverse magnetic field is considered.The proposed Cu–nanofluid consists of four different nanoparticles having different shapes,namely bricks,cylinders,platelets,and blades dispersed in a mixture of sodium alginate with Prandtl number Pr=6.45.Suitable similarity transformations are employed to reduce non–linear PDEs into a system of ODEs and these equations and related boundary conditions are solved numerically by means of a Runge–Kutta–Fehlberg(RKF)method.Moreover,analytical solutions are obtained through the application of a MAPLE built–in differential equation solver(Dsolve).The behavior of prominent parameters against velocity and temperature is analyzed.It is found that the temperature increases for all shapes of nanoparticles with the viscoplastic parameter and the Eckert number. 展开更多
关键词 NANOFLUID magnetic field viscous dissipation Dsolve
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An Innovative Technique for Constructing Highly Non-Linear Components of Block Cipher for Data Security against Cyber Attacks 被引量:1
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作者 Abid Mahboob Muhammad Asif +4 位作者 Rana Muhammad Zulqarnain Imran Siddique Hijaz Ahmad Sameh Askar Giovanni Pau 《Computer Systems Science & Engineering》 SCIE EI 2023年第11期2547-2562,共16页
The rapid advancement of data in web-based communication has created one of the biggest issues concerning the security of data carried over the internet from unauthorized access.To improve data security,modern cryptos... The rapid advancement of data in web-based communication has created one of the biggest issues concerning the security of data carried over the internet from unauthorized access.To improve data security,modern cryptosystems use substitution-boxes.Nowadays,data privacy has become a key concern for consumers who transfer sensitive data from one place to another.To address these problems,many companies rely on cryptographic techniques to secure data from illegal activities and assaults.Among these cryptographic approaches,AES is a well-known algorithm that transforms plain text into cipher text by employing substitution box(S-box).The S-box disguises the relationship between cipher text and the key to guard against cipher attacks.The security of a cipher using an S-box depends on the cryptographic strength of the respective S-box.Therefore,various researchers have employed different techniques to construct high order non-linear S-box.This paper provides a novel approach for evolving S-boxes using coset graphs for the action of the alternating group A5 over the finite field and the symmetric group S256.The motivation for this work is to study the symmetric group and coset graphs.The authors have performed various analyses against conventional security criteria such as nonlinearity,differential uniformity,linear probability,the bit independence criterion,and the strict avalanche criterion to determine its high cryptographic strength.To evaluate its image application performance,the proposed S-box is also used to encrypt digital images.The performance and comparison analyses show that the suggested S-box can secure data against cyber-attacks. 展开更多
关键词 Block cipher coset graphs S-BOX triangular group
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Magnetohydrodynamics hemodynamics hybrid nanofluid flow through inclined stenotic artery
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作者 B.K.SHARMA R.GANDHI +1 位作者 T.ABBAS M.M.BHATTI 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2023年第3期459-476,共18页
The present study aims to perform computational simulations of twodimensional(2D)hemodynamics of unsteady blood flow via an inclined overlapping stenosed artery employing the Casson fluid model to discuss the hemorheo... The present study aims to perform computational simulations of twodimensional(2D)hemodynamics of unsteady blood flow via an inclined overlapping stenosed artery employing the Casson fluid model to discuss the hemorheological properties in the arterial region.A uniform magnetic field is applied to the blood flow in the radial direction as the magneto-hemodynamics effect is considered.The entropy generation is discussed using the second law of thermodynamics.The influence of different shape parameters is explored,which are assumed to have varied shapes(spherical,brick,cylindrical,platelet,and blade).The Crank-Nicolson scheme solves the equations and boundary conditions governing the flow.For a given critical height of the stenosis,the key hemodynamic variables such as velocity,wall shear stress(WSS),temperature,flow rate,and heat transfer coefficient are computed. 展开更多
关键词 overlapping stenosis hematocrit-dependent viscosity Au-Cu/blood hybrid nanofluid entropy generation shape effect
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Multi-Attribute Group Decision-Making Method under Spherical Fuzzy Bipolar Soft Expert Framework with Its Application
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作者 Mohammed M.Ali Al-Shamiri Ghous Ali +1 位作者 Muhammad Zain Ul Abidin Arooj Adeel 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第11期1891-1936,共46页
Spherical fuzzy soft expert set(SFSES)theory blends the perks of spherical fuzzy sets and group decision-making into a unified approach.It allows solutions to highly complicated uncertainties and ambiguities under the... Spherical fuzzy soft expert set(SFSES)theory blends the perks of spherical fuzzy sets and group decision-making into a unified approach.It allows solutions to highly complicated uncertainties and ambiguities under the unbiased supervision and group decision-making of multiple experts.However,SFSES theory has some deficiencies such as the inability to interpret and portray the bipolarity of decision-parameters.This work highlights and overcomes these limitations by introducing the novel spherical fuzzy bipolar soft expert sets(SFBSESs)as a powerful hybridization of spherical fuzzy set theory with bipolar soft expert sets(BSESs).Followed by the development of certain set-theoretic operations and properties of the proposed model,important problems,including the selection of non-powered dam(NPD)sites for hydropower conversion are discussed and solved under the proposed approach.These problems mainly focus on the need for an efficient tool capable of considering the bipolarity of parameters,complicated ambiguities,and multiple opinions.Supporting the new approach by a detailed comparative analysis,it is concluded that the proposed model is more comprehensive and reliable for multi-attribute group decisionmaking(MAGDM)than the previous tools,particularly considering the bipolarity of parameters under SFSES environment. 展开更多
关键词 Spherical fuzzy sets bipolar soft expert sets group decision-making algorithm non-powered dams
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用人工神经网络混合元启发式优化技术分析不可压缩黏性流体在收敛和发散通道中的流动:一种智能方法
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作者 ASLAM Muhammad Naeem RIAZ Arshad +3 位作者 SHAUKAT Nadeem ALI Shahzad AKRAM Safia BHATTI M.M. 《Journal of Central South University》 SCIE EI CAS CSCD 2023年第12期4149-4167,共19页
本文采用人工神经网络(ANN)与进化算法(特别是阿基米德优化算法(AOA)和水循环算法(WCA)相结合的方法)对非线性磁流体动力学(MHD)的Jeffery-Hamel问题,特别是收敛和发散通道中的拉伸/收缩问题进行了数值研究。这种组合技术被称为ANN-AOA-... 本文采用人工神经网络(ANN)与进化算法(特别是阿基米德优化算法(AOA)和水循环算法(WCA)相结合的方法)对非线性磁流体动力学(MHD)的Jeffery-Hamel问题,特别是收敛和发散通道中的拉伸/收缩问题进行了数值研究。这种组合技术被称为ANN-AOA-WCA。将基于复杂非线性磁流体动力学Jeffery-Hamel问题的偏微分方程转化为速度和温度的非线性常微分方程系统,我们建立了基于人工神经网络的适应度函数来求解非线性微分问题。随后,采用了一种新的AOA和WCA结合方法(AOAWCA)来优化基于神经网络的适应度函数,并确定了神经网络的最优权值和偏差。为了证明提出混合方法的有效性和多功能性,探索了一系列雷诺数、通道角和可拉伸边界值的MHD模型,从而开发了两种不同的情况。ANN-AOA-WCA的数值结果与参考解(NDSOLVE)非常接近,NDSOLVE与ANNAOA-WCA的绝对误差约为3.35×10^(−8),对可拉伸收敛和发散通道的理解特别关键。此外,为了验证ANN-AOA-WCA技术,我们对150多个独立运行进行了统计分析,以获得适应度值。 展开更多
关键词 人工神经网络 阿基米德优化 水循环算法 拉伸/收缩表面 收敛或发散通道
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A Mathematical Approach for Generating a Highly Non-Linear Substitution Box Using Quadratic Fractional Transformation
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作者 Abid Mahboob Muhammad Asif +3 位作者 Rana Muhammad Zulqarnain Imran Saddique Hijaz Ahmad Sameh Askar 《Computers, Materials & Continua》 SCIE EI 2023年第11期2565-2578,共14页
Nowadays,one of the most important difficulties is the protection and privacy of confidential data.To address these problems,numerous organizations rely on the use of cryptographic techniques to secure data from illeg... Nowadays,one of the most important difficulties is the protection and privacy of confidential data.To address these problems,numerous organizations rely on the use of cryptographic techniques to secure data from illegal activities and assaults.Modern cryptographic ciphers use the non-linear component of block cipher to ensure the robust encryption process and lawful decoding of plain data during the decryption phase.For the designing of a secure substitution box(S-box),non-linearity(NL)which is an algebraic property of the S-box has great importance.Consequently,the main focus of cryptographers is to achieve the S-box with a high value of non-linearity.In this suggested study,an algebraic approach for the construction of 16×16 S-boxes is provided which is based on the fractional transformation Q(z)=1/α(z)^(m)+β(mod257)and finite field.This technique is only applicable for the even number exponent in the range(2-254)that are not multiples of 4.Firstly,we choose a quadratic fractional transformation,swap each missing element with repeating elements,and acquire the initial S-box.In the second stage,a special permutation of the symmetric group S256 is utilized to construct the final S-box,which has a higher NL score of 112.75 than the Advanced Encryption Standard(AES)S-box and a lower linear probability score of 0.1328.In addition,a tabular and graphical comparison of various algebraic features of the created S-box with many other S-boxes from the literature is provided which verifies that the created S-box has the ability and is good enough to withstand linear and differential attacks.From different analyses,it is ensured that the proposed S-boxes are better than as compared to the existing S-boxes.Further these S-boxes can be utilized in the security of the image data and the text data. 展开更多
关键词 Block cipher S-BOX data security fractional transformation
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Preliminary Report on the Anurans of Mount Hilong-hilong, Agusan Del Norte, Eastern Mindanao, Philippines 被引量:3
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作者 Jeszianlenn L.PLAZA Marites B.SANGUILA 《Asian Herpetological Research》 SCIE CSCD 2015年第1期18-33,共16页
Mount Hilong-hilong is a key biodiversity area, spanning several municipalities in the provinces of the Caraga Region (Agusan del Norte, Agusan del Sur, Surigao del Norte and Surigao del Sur), northeastern Mindanao ... Mount Hilong-hilong is a key biodiversity area, spanning several municipalities in the provinces of the Caraga Region (Agusan del Norte, Agusan del Sur, Surigao del Norte and Surigao del Sur), northeastern Mindanao Island, southern Philippines. The Hilong-hilong massif remains one of the most signiifcant forested areas in Mindanao, threatened with habitat modification (forest removal, degradation) and other anthropogenic disturbances related to renewable resource extraction. Amphibians are key indicator species for environmental quality and are useful focal taxa for conservation efforts. Relying on historical museum database information and new survey work on Mount Hilong-hilong, we provide species accounts and describe microhabitat preferences of the anurans (frogs and toads) present in the area. Twenty-seven species representing seven anuran families were studied in detail at elevations between 700 to 1300 meters above sea level; 16 of these species are Mindanao faunal region endemics. Qualitative overlap in microhabitat use was observed, suggesting that, for the species recorded, intact forest may ensure species persistence to some levels of anthropogenic disturbance. A more extensive herpetofaunal survey is needed to fully estimate the herpetofaunal diversity of Mount Hilong-hilong. Because amphibians represent ifne-scale indicators of environmental quality and microendemism, we recommend appropriate ifne-scaled regional strategies geared towards the conservation of amphibians in the Caraga area, northeast Mindanao Island. 展开更多
关键词 environmental indicator species key biodiversity areas species accounts historical records microhabitat preferences anthropogenic disturbance
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Legendre Rational Spectral Method for Nonlinear Klein-Gordon Equation 被引量:3
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作者 Zhongqing Wang Benyu Guo 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 2006年第2期143-149,共7页
A Legendre rational spectral method is proposed for the nonlinear Klein-Gordon equation on the whole line. Its stability and convergence are proved. Numerical results coincides well with the theoretical analysis and d... A Legendre rational spectral method is proposed for the nonlinear Klein-Gordon equation on the whole line. Its stability and convergence are proved. Numerical results coincides well with the theoretical analysis and demonstrate the e?ciency of this approach. 展开更多
关键词 勒让德有理数光谱方法 非线性方程 克莱因-戈登方程 收敛 稳定性
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Comparison of typhoon-induced near-inertial oscillations in shear flow in the northern South China Sea 被引量:4
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作者 SUN Zhenyu HU Jianyu +1 位作者 ZHENG Quanan GAN Jianping 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2015年第11期38-45,共8页
With moorings equipped with Acoustic Doppler Current Profilers (ADCP) in the northern South China Sea (SCS) in 2008 and 2009, we observed three near-inertial oscillation (NIO) events coded 2008a, 2009a and 2009b... With moorings equipped with Acoustic Doppler Current Profilers (ADCP) in the northern South China Sea (SCS) in 2008 and 2009, we observed three near-inertial oscillation (NIO) events coded 2008a, 2009a and 2009b induced by passages of typhoons or tropical storms. This study compares characteristics of the three NIO events. Event 2008a was the strongest one among the three, and had the longest sustaining period (15 d), while events 2009a and 2009b sustained for only 4 and 8 d, respectively. The three events were distinguished by vertical energy distribution and phase propagation. As for the frequency shift of the NIO, event 2008a had a peak frequency lower than the local Coriolis frequency (red-shift), while events 2009a and 2009b showed blue-shift. The behavior of individual NIO event is jointly decided by the typhoon disturbance and the background ocean condition. Especially the background flow plays an important role by effects of advection and modulation. The results in this study provide observational evidence of variational NIO response to background flow field. As indicated by the distribution of vorticity and effective Coriolis frequency derived from numerical modeling, the large amplitude and elongated sustaining period of event 2008a were attributed to the waveguide effect of the background shear flow. This effect redistributed the NIO energy after the typhoon passage, absorbed incident waves and trapped energy in the area of the negative vorticity. While the background flow during events 2009a and 2009b did not have such effects due to the near-zero vorticity in the mooring area. 展开更多
关键词 near-inertial oscillation TYPHOON northern South China Sea
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SOME DOUBLE SEQUENCE SPACES OF FUZZY NUMBERS DEFINED BY ORLICZ FUNCTIONS 被引量:1
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作者 Binod Chandra Tripathy Bipul Sarma 《Acta Mathematica Scientia》 SCIE CSCD 2011年第1期134-140,共7页
In this article, we introduce some double sequence spaces of fuzzy real numbers defined by Orlicz function, study some of their properties like solidness, symmetricity, completeness etc, and prove some inclusion results.
关键词 Orlicz function COMPLETENESS SEMINORM regular convergence solid space symmetric space
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关于一类p-赋范空间l^p的关联序列(英文) 被引量:1
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作者 TRIPATHYBinodChandra SENMausumi 《北京工业大学学报》 CAS CSCD 北大核心 2005年第5期553-556,共4页
引进了序列空间m(φ,p),0<p<1,它在空间lp,p>1和序列空间m(φ)相关联,并研究了户p-赋范空间m(φ,p)的性质.
关键词 对称空间 正则空间 完全性 P-赋范空间 K-空间
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Life prognosis of sentinel node navigation surgery for early-stage gastric cancer:Outcome of lymphatic basin dissection 被引量:5
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作者 Shinichi Kinami Naohiko Nakamura +7 位作者 Tomoharu Miyashita Hidekazu Kitakata Sachio Fushida Takashi Fujimura Yasuo Iida Noriyuki Inaki Toru Ito Hiroyuki Takamura 《World Journal of Gastroenterology》 SCIE CAS 2021年第46期8010-8030,共21页
BACKGROUND Lymphatic basin dissection is a sentinel node biopsy method that is specific for gastric cancer.In this method,the dyed lymphatic system is dissected en bloc,and sentinel nodes are identified at the back ta... BACKGROUND Lymphatic basin dissection is a sentinel node biopsy method that is specific for gastric cancer.In this method,the dyed lymphatic system is dissected en bloc,and sentinel nodes are identified at the back table(ex vivo).Even with lymphatic basin dissection,blood flow to the residual stomach can be preserved,and functionpreserving curative gastrectomy can be performed.The oncological safety of function-preserving curative gastrectomy combined with lymphatic basin dissection has not yet been fully investigated.We hypothesized that the oncological safety of sentinel node navigation surgery(SNNS)is not inferior to that of the guidelines.AIM To investigate the life prognosis of SNNS for gastric cancer in comparison with guidelines surgery.METHODS This was a retrospective cohort study.Patients were selected from gastric cancer patients who underwent sentinel node biopsy from April 1999 to March 2016.Patients from April 1999 to August 2008 were from the Department of Surgery II,Kanazawa University Hospital,and patients from August 2009 to March 2016 were from the Department of Surgical Oncology,Kanazawa Medical University Hospital.Patients who were diagnosed with gastric cancer,which was preoperatively diagnosed as superficial type(type 0),5 cm or less in length,clinical T1-2 and node negative,and underwent various gastrectomies guided by sentinel node navigation were retrospectively collected.The overall survival(OS)and relapsefree survival(RFS)of these patients(SNNS group)were investigated.Patients with gastric cancer of the same stage and who underwent guidelines gastrectomy with standard nodal dissection were also selected as the control group.RESULTS A total of 239 patients in the SNNS group and 423 patients in the control group were included.Pathological nodal metastasis was observed in 10.5%and 10.4%of the SNNS and control groups,respectively.The diagnostic abilities of sentinel node biopsy were 84%and 98.6%for sensitivity and accuracy,respectively.In the SNNS group,81.6%of patients underwent modified gastrectomy or functionpreserving curative gastrectomy with lymphatic basin dissection,in which the extent of nodal dissection was further reduced compared to the guidelines.The OS rate in the SNNS group was 96.8%at 5 years and was significantly better than 91.3%in the control group(P=0.0014).The RFS rates were equal in both groups.After propensity score matching,there were 231 patients in both groups,and the cumulative recurrence rate was 0.43%at 5 years in the SNNS group and 1.30%in the control group,which was not statistically different.CONCLUSION The oncological safety of patients who undergo gastrectomy guided by sentinel node navigation is not inferior to that of the guidelines surgery. 展开更多
关键词 Early gastric cancer Sentinel node biopsy Function preserving surgery Lymph node dissection GASTRECTOMY Lymphatic basin dissection
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Significance of induced magnetic field and variable thermal conductivity on stagnation point flow of second grade fluid 被引量:2
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作者 A.A.KHAN S.ILYAS +1 位作者 T.ABBAS R.ELLAHI 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第11期3381-3390,共10页
In this study,the stagnation point transport of second grade fluid with linear stretching under the effects of variable thermal conductivity is considered.Induced magnetic field impact is also incorporated.The nonline... In this study,the stagnation point transport of second grade fluid with linear stretching under the effects of variable thermal conductivity is considered.Induced magnetic field impact is also incorporated.The nonlinear set of particle differential equations is converted into set of ordinary differential equations through appropriate transformation.The resulting equations are then resolved by optimal homotopy analysis method.The effect of pertinent parameters of interest on skin friction coefficient,temperature,induced magnetic field,velocity and local Nusselt number is inspected by generating appropriate plots.For numerical results,the built-in bvp4 c technique in computational software MATLAB is used for the convergence and residual errors of obtained series solution.It is perceived that the induced magnetic field is intensified by increasing β.It can also be observed that skin friction coefficient enhances with increasing value of magnetic parameter depending on the stretching ratio a/c.For the validness of the obtained results,a comparison has been made and an excellent agreement of current study with existing literature is found. 展开更多
关键词 stagnation point variable thermal conductivity induced magnetic field second grade fluid
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Determination of Wood Moisture Properties Using a CT-Scanner in a Controlled High-Temperature Environment 被引量:2
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作者 Lars Hansson Ekaterina Cherepanova 《Journal of Civil Engineering and Architecture》 2012年第3期372-378,共7页
Theaim of the present work wasto analyze moisture flow and moisture content data for high-temperature drying by usingan advanced image- processing algorithm.Since wood starts to shrink below the fibre saturation point... Theaim of the present work wasto analyze moisture flow and moisture content data for high-temperature drying by usingan advanced image- processing algorithm.Since wood starts to shrink below the fibre saturation point during drying, the size and shape of wood will change. The dry wood image was thoroughly transformed to the shape of the wet wood image prior to calculating the dry weight moisture content. The use of the image- processing algorithm for the dry weight moisture content on density data from the CT-scanning during drying in a controlled high-temperature environment showed that this method is a powerful tool for analyzing the moisture flow inside the wood piece. Furthermore, the new CT-scanner together with the climate chamber gave unique results, as it has not been possible to study high-temperature drying with this method before. 展开更多
关键词 CT-scanning fibre saturation point high-temperature drying image analysis moisture content wood drying.
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DISTRIBUTIONS ON ALMOST CONTACT MANIFOLDS
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作者 Hyunjoo CHO 《Acta Mathematica Scientia》 SCIE CSCD 2017年第3期695-702,共8页
It is known that any hypersurface in an almost complex space admits an almost contact manifold [11, 14]. In this article we show that a hyperplane in an almost contact manifold has an almost complex structure. Along w... It is known that any hypersurface in an almost complex space admits an almost contact manifold [11, 14]. In this article we show that a hyperplane in an almost contact manifold has an almost complex structure. Along with this result, we explain how to deter- mine when an almost contact structure induces a contact structure, followed by examples of a manifold with a closed G2-structure. 展开更多
关键词 Almost contact structure contact structure G2-structure FOLIATION integra-bility
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A NEW ALGORITHM FOR COMPUTING LARGEST REAL PART EIGENVALUE OF MATRICES:COLLATZ & PERRON-FROBERNIUS' APPROACH
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作者 Tedja Santanoe Oepomo 《Acta Mathematica Scientia》 SCIE CSCD 2011年第3期1189-1202,共14页
This paper describes a new method and algorithm for the numerical solution of eigenvalues with the largest real part of positive matrices.The method is based on a numerical implementation of Collatz's eigenvalue incl... This paper describes a new method and algorithm for the numerical solution of eigenvalues with the largest real part of positive matrices.The method is based on a numerical implementation of Collatz's eigenvalue inclusion theorem for non-negative irreducible matrices.Eigenvalues are analyzed for the studies of the stability of linear systems.Finally, a numerical discussion is given to derive the required number of mathematical operations of the new algorithm. Comparisons between the new algorithm and several well known ones, such as Power, and QR methods, are discussed. 展开更多
关键词 Collatz’s theorem Perron-Frobernius’theorem EIGENVALUE
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Hybrid Surface Mesh Adaptation for Climate Modeling
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作者 Ahmed Khamayseh Valmor de Almeida Glen Hansen 《Numerical Mathematics(Theory,Methods and Applications)》 SCIE 2008年第4期410-434,共25页
Solution-driven mesh adaptation is becoming quite popular for spatial error control in the numerical simulation of complex computational physics applications,such as climate modeling.Typically,spatial adaptation is ac... Solution-driven mesh adaptation is becoming quite popular for spatial error control in the numerical simulation of complex computational physics applications,such as climate modeling.Typically,spatial adaptation is achieved by element subdivision (h adaptation) with a primary goal of resolving the local length scales of interest.A sec- ond,less-popular method of spatial adaptivity is called'mesh motion'(r adaptation); the smooth repositioning of mesh node points aimed at resizing existing elements to capture the local length scales.This paper proposes an adaptation method based on a combination of both element subdivision and node point repositioning (rh adaptation). By combining these two methods using the notion of a mobility function,the proposed approach seeks to increase the flexibility and extensibility of mesh motion algorithms while providing a somewhat smoother transition between refined regions than is pro- duced by element subdivision alone.Further,in an attempt to support the requirements of a very general class of climate simulation applications,the proposed method is de- signed to accommodate unstructured,polygonal mesh topologies in addition to the most popular mesh types. 展开更多
关键词 surface mesh generation mesh adaptation mesh optimization climate modeling.
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The Distribution of Prime Numbers and Finding the Factor of Composite Numbers without Searching
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作者 Dagnachew Jenber 《Advances in Pure Mathematics》 2015年第6期338-352,共15页
In this paper, there are 5 sections of tables represented by 5 linear sequence functions. There are two one-variable sequence functions that they are able to represent all prime numbers. The first one helps the last o... In this paper, there are 5 sections of tables represented by 5 linear sequence functions. There are two one-variable sequence functions that they are able to represent all prime numbers. The first one helps the last one to produce another three two-variable linear sequence functions. With the help of these three two-variable sequence functions, the last one, one-variable sequence function, is able to set apart all prime numbers from composite numbers. The formula shows that there are infinitely many prime numbers by applying limit to infinity. The three two-variable sequence functions help us to find the factor of all composite numbers. 展开更多
关键词 The nth SEQUENCE of an ARITHMETIC SEQUENCE NUMBER of Elements of the Set SEQUENCE FUNCTIONS
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