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关于Directly—Riemann积分的进一步属性 被引量:2
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作者 熊启才 王树勋 +2 位作者 郭天印 曹吉利 杨立夫 《陕西工学院学报》 2002年第1期75-78,共4页
在Directly—Riemann积分条件下 ,给出了积分绝对连续性以及连续函数逼近性等几个重要的积分性质。
关键词 directly-riemann积分 可测集 属性
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Directly—Riemann积分的重要性质 被引量:2
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作者 熊启才 王树勋 《陕西工学院学报》 2001年第4期59-61,94,共4页
利用文 [3 ,4]有关性质 ,得到了Directly—Riemann积分的一些重要性质。
关键词 directly-riemann积分 性质 可测函数
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关于Directly—Riemann积分的几个重要性质
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作者 熊启才 库热西.沙吾提 《新疆师范大学学报(自然科学版)》 1995年第1期22-25,共4页
本文在[1]、[2]的基础上进一步研究了Directly—Riemann积分的性质,得到几个重要的结果。
关键词 directly—riemann 积分 性质
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关于Directly—Riemann积分极限定理又一注记
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作者 熊启才 洪歧 +1 位作者 杨明安 冯甄玲 《陕西工学院学报》 2001年第1期59-61,83,共4页
在Directly—Riemann积分条件下 。
关键词 directly-riemann积分 函数列 极根定理 可积函数 广义-致收敛
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关于Directly-Riemann积分、Lebesgue积分与Riemann积分的相互关系
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作者 熊启才 和来香 张志学 《喀什师范学院学报》 2003年第3期18-21,共4页
利用 Directly- Riemann积分、Lebesgue积分及 Riemann积分的有关性质 ,得到了 Directly-Riemann积分可积条件以及它们之间的相互关系 .
关键词 directly—riemann积分 LEBESGUE积分 riemann积分 可积条件 相互关系
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关于Directly-Riemann积分Dirichlet和Abel判别法的充要性 被引量:3
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作者 熊启才 洪歧 《宝鸡文理学院学报(自然科学版)》 CAS 2001年第1期26-27,38,共3页
证明了 Directly-Riemann积分 Dirichlet判别法和 Abel判别法的必要性 ,而 Directly-Riemann积分的 Dirichlet判别法和 Abel判别法充分性熊启才已有证明 ,由此说明这 2个重要判别法不仅充分而且必要。
关键词 directly-riemann积分 Dirichlet判别法 Abel判别法收敛 (D-R)可积
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关于Directly-Riemann积分的进一步性质 被引量:15
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作者 李泽慧 熊启才 《西北师范大学学报(自然科学版)》 CAS 1994年第4期37-40,共4页
在文献[1]、[2]的基础上进一步研究了Directly-Riemann积分的性质,得到了如下结果:(1)函数f(x)(D-R)积分值唯一的条件。(2)截断函数f_n(x)(D-R)可积的条件。(3)非负函数f(x)... 在文献[1]、[2]的基础上进一步研究了Directly-Riemann积分的性质,得到了如下结果:(1)函数f(x)(D-R)积分值唯一的条件。(2)截断函数f_n(x)(D-R)可积的条件。(3)非负函数f(x)(D-R)可积的充要条件。 展开更多
关键词 可测集 可测函数 D-R积分 广义勒贝格积分
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关于Directly-Riemann积分的极限定理 被引量:7
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作者 刘锋 熊启才 《陕西工学院学报》 1999年第2期63-67,共5页
提出并着重研究了Directly—Riemann积分的极限定理。
关键词 可测集 积分 极限定理 D-R积分
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关于Directly-Riemann积分收敛性判别法
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作者 熊启才 何广平 刘淳安 《武汉科技大学学报》 CAS 2002年第4期431-432,共2页
利用Directly Riemann积分的基本性质,研究了判别Directly Riemann积分的收敛性问题。
关键词 directly-riemann积分 收敛性 判别法 非负可积函数 LEBESGUE可积
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关于Directly——Riemann积分的Riemann定理
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作者 熊启才 洪歧 冯甄玲 《陕西工学院学报》 2001年第2期42-45,共4页
在Fourier级数的收敛理论中 ,Riemann引理 (Riemann积分意义下 )起到了非常重要的作用。
关键词 directly-riemann积分 FOURIER级数 riemann定理 收敛理论 广义Lebesgue积分 可积函数
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边加权有限图的Weil-Riemann-Roch定理
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作者 曹廷彬 刘洁 《南昌大学学报(理科版)》 CAS 2024年第2期103-107,共5页
Riemann-Roch定理是数学中的一个重要结论,并有了广泛的应用。在有限图和边加权有限图等图中也有对应的Riemann-Roch定理以及应用,但所有这些工作都有一个共同点,那就是它们都聚焦于在除子或和除子线性等价的线丛的情况下,也就是秩为1... Riemann-Roch定理是数学中的一个重要结论,并有了广泛的应用。在有限图和边加权有限图等图中也有对应的Riemann-Roch定理以及应用,但所有这些工作都有一个共同点,那就是它们都聚焦于在除子或和除子线性等价的线丛的情况下,也就是秩为1的情况。为了得到高维秩的情形,可以借助多重除子的术语来描述。本文利用还原群GLn的root datum的概念给出了边加权有限图上主GLn-丛——向量丛的定义,并用多重除子的术语来描述向量丛,进而给出了边加权有限图的Weil-Riemann-Roch定理以及证明,推广了GROSS A.ULIRSCH M.和ZAKHAROV D的结果。 展开更多
关键词 边加权有限图 riemann-Roch定理 向量丛 多重除子
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关于Directly-Riemann积分的Hilbert不等式
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作者 熊启才 曹吉利 +1 位作者 王树勋 刘德斌 《陕西工学院学报》 2004年第1期81-84,共4页
 利用Directly Riemann积分的性质,定义了一类新型卷积积分。将著名的Hilbert不等式推广为Hilbert积分不等式形式。
关键词 directly-riemann积分 HILBERT不等式 卷积不等式 卷积积分 积分不等式
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Directly——Riemann积分极限定理(Ⅱ)
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作者 熊启才 王树勋 张志学 《陕西工学院学报》 2002年第3期67-69,共3页
利用文 [1— 1 0 ]有关基本理论 ,给出了Directly———Riemann积分几个重要极限定理。
关键词 可测集 directly-riemann积分 极限定理 随机过程 可测函数 (D-R)可积函数
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关于Directly-Riemann积分的属性
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作者 熊启才 胡明娣 《安康师专学报》 2001年第3期57-58,共2页
在文〔1〕 -〔4〕的基础上 ,给出了Directly -Riemann积分的几个性质 ;(i)Directly -Rie mann积分的绝对可积性 ;(ii)Directly -Riemann积分的绝对连续性 .
关键词 directly-riemann积分 绝对可积性 绝对连续性
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SlWRKY30 and SlWRKY81 synergistically modulate tomato immunity to Ralstonia solanacearum by directly regulating SlPR-STH2 被引量:2
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作者 Fengfeng Dang Jinhui Lin +5 位作者 Yajing Li Ruoyun Jiang Yudong Fang Fei Ding Shuilin He Yanfeng Wang 《Horticulture Research》 SCIE CSCD 2023年第5期99-111,共13页
Bacterial wilt is a devastating disease of tomato(Solanum lycopersicum)caused by Ralstonia solanacearum that severely threatens tomato production.Group III WRKY transcription factors(TFs)are implicated in the plant re... Bacterial wilt is a devastating disease of tomato(Solanum lycopersicum)caused by Ralstonia solanacearum that severely threatens tomato production.Group III WRKY transcription factors(TFs)are implicated in the plant response to pathogen infection;however,their roles in the response of tomato to R.solanacearum infection(RSI)remain largely unexplored.Here,we report the crucial role of SlWRKY30,a group III SlWRKY TF,in the regulation of tomato response to RSI.SlWRKY30 was strongly induced by RSI.SlWRKY30 overexpression reduced tomato susceptibility to RSI,and also increased H2O2 accumulation and cell necrosis,suggesting that SlWRKY30 positively regulates tomato resistance to RSI.RNA sequencing and reverse transcription–quantitative PCR revealed that SlWRKY30 overexpression significantly upregulated pathogenesis-related protein(SlPR-STH2)genes SlPR-STH2a,SlPR-STH2b,SlPR-STH2c,and SlPR-STH2d(hereafter SlPR-STH2a/b/c/d)in tomato,and these SlPR-STH2 genes were directly targeted by SlWRKY30.Moreover,four group III WRKY proteins(SlWRKY52,SlWRKY59,SlWRKY80,and SlWRKY81)interacted with SlWRKY30,and SlWRKY81 silencing increased tomato susceptibility to RSI.Both SlWRKY30 and SlWRKY81 activated SlPR-STH2a/b/c/d expression by directly binding to their promoters.Taking these results together,SlWRKY30 and SlWRKY81 synergistically regulate resistance to RSI by activating SlPR-STH2a/b/c/d expression in tomato.Our results also highlight the potential of SlWRKY30 to improve tomato resistance to RSI via genetic manipulations. 展开更多
关键词 directly SYNERGISTIC IMMUNITY
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Directly-Riemann积分的一个重要不等式
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作者 熊启才 《喀什师范学院学报》 2003年第6期11-13,共3页
利用Directly-Riemann积分相关性质,给出了Directly-Riemann积分的一个重要不等式.
关键词 directly-riemann积分 单调函数 不等式 第二积分中值定理 级数
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Anisotropic time-dependent behaviors of shale under direct shearing and associated empirical creep models 被引量:2
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作者 Yachen Xie Michael Z.Hou +1 位作者 Hejuan Liu Cunbao Li 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第4期1262-1279,共18页
Understanding the anisotropic creep behaviors of shale under direct shearing is a challenging issue.In this context,we conducted shear-creep and steady-creep tests on shale with five bedding orientations (i.e.0°,... Understanding the anisotropic creep behaviors of shale under direct shearing is a challenging issue.In this context,we conducted shear-creep and steady-creep tests on shale with five bedding orientations (i.e.0°,30°,45°,60°,and 90°),under multiple levels of direct shearing for the first time.The results show that the anisotropic creep of shale exhibits a significant stress-dependent behavior.Under a low shear stress,the creep compliance of shale increases linearly with the logarithm of time at all bedding orientations,and the increase depends on the bedding orientation and creep time.Under high shear stress conditions,the creep compliance of shale is minimal when the bedding orientation is 0°,and the steady-creep rate of shale increases significantly with increasing bedding orientations of 30°,45°,60°,and 90°.The stress-strain values corresponding to the inception of the accelerated creep stage show an increasing and then decreasing trend with the bedding orientation.A semilogarithmic model that could reflect the stress dependence of the steady-creep rate while considering the hardening and damage process is proposed.The model minimizes the deviation of the calculated steady-state creep rate from the observed value and reveals the behavior of the bedding orientation's influence on the steady-creep rate.The applicability of the five classical empirical creep models is quantitatively evaluated.It shows that the logarithmic model can well explain the experimental creep strain and creep rate,and it can accurately predict long-term shear creep deformation.Based on an improved logarithmic model,the variations in creep parameters with shear stress and bedding orientations are discussed.With abovementioned findings,a mathematical method for constructing an anisotropic shear creep model of shale is proposed,which can characterize the nonlinear dependence of the anisotropic shear creep behavior of shale on the bedding orientation. 展开更多
关键词 Rock anisotropy direct shear creep Creep compliance Steady-creep rate Empirical model Creep constitutive model
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Theoretical analysis of hydrogen solubility in direct coal liquefaction solvents 被引量:1
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作者 Xiaobin Zhang Aoqi Wang +1 位作者 Xingbao Wang Wenying Li 《International Journal of Coal Science & Technology》 EI CAS CSCD 2024年第2期187-197,共11页
The cyclic hydrogenation technology in a direct coal liquefaction process relies on the dissolved hydrogen of the solvent or oil participating in the hydrogenation reaction.Thus,a theoretical basis for process optimiz... The cyclic hydrogenation technology in a direct coal liquefaction process relies on the dissolved hydrogen of the solvent or oil participating in the hydrogenation reaction.Thus,a theoretical basis for process optimization and reactor design can be established by analyzing the solubility of hydrogen in liquefaction solvents.Experimental studies of hydrogen solubility in liquefaction solvents are challenging due to harsh reaction conditions and complex solvent compositions.In this study,the composition and content of liquefied solvents were analyzed.As model compounds,hexadecane,toluene,naphthalene,tetrahydronaphthalene,and phenanthrene were chosen to represent the liquefied solvents in chain alkanes and monocyclic,bicyclic,and tricyclic aromatic hydrocarbons.The solubility of hydrogen X(mol/mol)in pure solvent components and mixed solvents(alkanes and aromatics mixed in proportion to the chain alkanes+bicyclic aromatic hydrocarbons,bicyclic saturated aromatic hydrocarbons+bicyclic aromatic hydrocarbons,and bicyclic aromatic hydrocarbons+compounds containing het-eroatoms composed of mixed components)are determined using Aspen simulation at temperature and pressure conditions of 373–523 K and 2–10 MPa.The results demonstrated that at high temperatures and pressures,the solubility of hydrogen in the solvent increases with the increase in temperature and pressure,with the pressure having a greater impact.Further-more,the results revealed that hydrogen is more soluble in straight-chain alkanes than in other solvents,and the solubility of eicosanoids reaches a maximum of 0.296.The hydrogen solubility in aromatic ring compounds decreased gradually with an increase in the aromatic ring number.The influence of chain alkanes on the solubility of hydrogen predominates in a mixture of solvents with different mixing ratios of chain alkanes and aromatic hydrocarbons.The solubility of hydrogen in mixed aromatic solvents is less than that in the corresponding single solvents.Hydrogen is less soluble in solvent compounds containing heteroatoms than in compounds without heteroatoms. 展开更多
关键词 direct coal liquefaction Liquefaction solvents Process simulation Hydrogen solubility
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Complication rates after direct anterior vs posterior approach for hip hemiarthroplasty in elderly individuals with femoral neck fractures 被引量:2
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作者 Tatiana Charles Nicolas Bloemers +1 位作者 Bilal Kapanci Marc Jayankura 《World Journal of Orthopedics》 2024年第1期22-29,共8页
BACKGROUND Dislocation rates after hemiarthroplasty reportedly vary from 1%to 17%.This serious complication is associated with increased morbidity and mortality rates.Approaches to this surgery are still debated,with ... BACKGROUND Dislocation rates after hemiarthroplasty reportedly vary from 1%to 17%.This serious complication is associated with increased morbidity and mortality rates.Approaches to this surgery are still debated,with no consensus regarding the superiority of any single approach.AIM To compare early postoperative complications after implementing the direct anterior and posterior approaches(PL)for hip hemiarthroplasty after femoral neck fractures.METHODS This is a comparative,retrospective,single-center cohort study conducted at a university hospital.Between March 2008 and December 2018,273 patients(a total of 280 hips)underwent bipolar hemiarthroplasties(n=280)for displaced femoral neck fractures using either the PL(n=171)or the minimally invasive direct anterior approach(DAA)(n=109).The choice of approach was related to the surgeons’practices;the implant types were similar and unrelated to the approach.Dislocation rates and other complications were reviewed after a minimum followup of 6 mo.RESULTS Both treatment groups had similarly aged patients(mean age:82 years),sex ratios,patient body mass indexes,and patient comorbidities.Surgical data(surgery delay time,operative time,and blood loss volume)did not differ significantly between the groups.The 30 d mortality rate was higher in the PL group(9.9%)than in the DAA group(3.7%),but the difference was not statistically significant(P=0.052).Among the one-month survivors,a significantly higher rate of dislocation was observed in the PL group(14/154;9.1%)than in the DAA group(0/105;0%)(P=0.002).Of the 14 patients with dislocation,8 underwent revision surgery for recurrent instability(posterior group),and one of them had 2 additional procedures due to a deep infection.The rate of other complications(e.g.,perioperative and early postoperative periprosthetic fractures and infection-related complications)did not differ significantly between the groups.CONCLUSION These findings suggest that the DAA to bipolar hemiarthroplasty for patients with femoral neck fractures is associated with a lower dislocation rate(<1%)than the PL. 展开更多
关键词 HEMIARTHROPLASTY Femoral neck fracture direct anterior approach Posterior approach DISLOCATION MORTALITY
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Review on laser directed energy deposited aluminum alloys 被引量:2
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作者 Tian-Shu Liu Peng Chen +7 位作者 Feng Qiu Hong-Yu Yang Nicholas Tan Yew Jin Youxiang Chew Di Wang Ruidi Li Qi-Chuan Jiang Chaolin Tan 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第2期84-131,共48页
Lightweight aluminum(Al)alloys have been widely used in frontier fields like aerospace and automotive industries,which attracts great interest in additive manufacturing(AM)to process high-value Al parts.As a mainstrea... Lightweight aluminum(Al)alloys have been widely used in frontier fields like aerospace and automotive industries,which attracts great interest in additive manufacturing(AM)to process high-value Al parts.As a mainstream AM technique,laser-directed energy deposition(LDED)shows good scalability to meet the requirements for large-format component manufacturing and repair.However,LDED Al alloys are highly challenging due to their inherent poor printability(e.g.low laser absorption,high oxidation sensitivity and cracking tendency).To further promote the development of LDED high-performance Al alloys,this review offers a deep understanding of the challenges and strategies to improve printability in LDED Al alloys.The porosity,cracking,distortion,inclusions,element evaporation and resultant inferior mechanical properties(worse than laser powder bed fusion)are the key challenges in LDED Al alloys.Processing parameter optimizations,in-situ alloy design,reinforcing particle addition and field assistance are the efficient approaches to improving the printability and performance of LDED Al alloys.The underlying correlations between processes,alloy innovation,characteristic microstructures,and achievable performances in LDED Al alloys are discussed.The benchmark mechanical properties and primary strengthening mechanism of LDED Al alloys are summarized.This review aims to provide a critical and in-depth evaluation of current progress in LDED Al alloys.Future opportunities and perspectives in LDED high-performance Al alloys are also outlined. 展开更多
关键词 additive manufacturing laser directed energy deposition(LDED) aluminum alloys PRINTABILITY aluminum matrix composite auxiliary fields mechanical properties
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