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Limiting Property of the Distribution Function of L^p Function at Endpoints 被引量:1
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作者 Shaozhen XU Dunyan YAN 《Journal of Mathematical Research with Applications》 CSCD 2016年第2期177-182,共6页
We consider the limiting property of the distribution function of L^p function at endpoints 0 and ∞ and prove that for λ 〉 0 the following two equations limλ→+∞λ^p({x : |f(x)| 〉 λ}) = 0, limλ→0+λ^... We consider the limiting property of the distribution function of L^p function at endpoints 0 and ∞ and prove that for λ 〉 0 the following two equations limλ→+∞λ^p({x : |f(x)| 〉 λ}) = 0, limλ→0+λ^p({x : |f(x)| 〉 λ}) = 0hold for f ∈ L^p(Rn) with 1 ≤ p 〈 ∞. This result is naturally applied to many operators of type(p, q) as well. 展开更多
关键词 Hardy-Littlewood maximal function limiting behavior distribution function
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THE AUTOMATIC GENERATION OF LIMIT STATE FUNCTION OF HINGED STRUCTURE
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作者 车维毅 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1991年第12期1187-1193,共7页
In this paper, the theorem of structure continual variation of truss structure in the analysis of structure reliability is derived, and it is used to generate limit state function automatically. We can avoid repeated ... In this paper, the theorem of structure continual variation of truss structure in the analysis of structure reliability is derived, and it is used to generate limit state function automatically. We can avoid repeated assembly of global stiffness matrix and repeated inverse operations of the matrix caused by constant changes of structure topology. A new criterion of degenerate of the structure into mechanism is introduced. The calculation examples are satisfactory. 展开更多
关键词 hinged structure continual variation theorem limit state function
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THE SPHERICAL FUNCTIONS AND THE CENTRAL LIMIT THEOREM ON SU(2,2)/S(U(2)×U(2))
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作者 杨乔华 张钦 《Acta Mathematica Scientia》 SCIE CSCD 2007年第4期867-874,共8页
Let G = SU(2, 2), K = S(U(2) × U(2)), and for l ∈ Z, let {Tl}l∈z be a one-dimensional K-type and let El be the line bundle over G/K associated to Tl. It is shown that the Tl-spherical function on G is g... Let G = SU(2, 2), K = S(U(2) × U(2)), and for l ∈ Z, let {Tl}l∈z be a one-dimensional K-type and let El be the line bundle over G/K associated to Tl. It is shown that the Tl-spherical function on G is given by the hypergeometric functions of several variables. By applying this result, a central limit theorem for the space G/K is obtained. 展开更多
关键词 Spherical function central limit theorem hypergeometric function
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Assessment of the 2 Conventional Physiotherapy Sessions Alone versus One Session Associated to Kabat’s Method in the Rehabilitation of Buruli Ulcer Patients (PUB), with Functional Limitations in the District Hospital of Akonolinga, Cameroon
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作者 Fred Dikongue Dikongue Faustin Tsatedem Atemkeng +4 位作者 Joseph Fondop Jean Hubert Donfack Alain Djam Nkomo Banga Mbida Mpoame 《Surgical Science》 2023年第6期428-435,共8页
Buruli ulcer (BU) is a chronic, indolent necrotizing disease of the skin and underlying tissues caused by Mycobacterium ulcerans, which may result in functional disability. This disease is the third most frequent infe... Buruli ulcer (BU) is a chronic, indolent necrotizing disease of the skin and underlying tissues caused by Mycobacterium ulcerans, which may result in functional disability. This disease is the third most frequent infection after leprosy and tuberculosis caused by a mycobacterium. The main objective of this study was to determine comparative effectiveness of conventional physiotherapy alone to its association with Kabat’s method in the management of post-Buruli ulcer functional limitations. This was an interventional randomized, comparative and prospective study. It took place at the district hospital of Akonolinga from the 12<sup>th</sup> June to 12<sup>th</sup> September 2016. The study was included, post-Buruli ulcer patients who matched the eligibility criteria, were under treatment in the physiotherapy unit, and who accepted to participate in our study. A questionnaire on the socio-demographic profile of participants, the ulcer localization, the limitation stage, previous medical history and functional mobility assessment scale was administered to the subjects before and after the intervention which lasted for twelve weeks. We had 2 groups: the case group received association of Kabat technique to conventional physiotherapy and the control group received conventional physiotherapy alone. We had 22 patients, 11 patients for the experimental group, 11 patients for the control group. The mean age was 26.18 years, 54.5% of female participation, 68.2% of leg localization, 59.1% patients with severe limitations of functional mobility, and preference for traditional medication 95.5%. After evaluation of efficiency, we concluded that there was no statistically significant difference between the two treatment protocols. Further studies with larger sample size are recommended. 展开更多
关键词 Buruli Ulcer functional limitations PHYSIOTHERAPY Kabat Technique
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A Class of Strong Limit Theorems and Moment Generating Function Method 被引量:1
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作者 Wen Hart LI Gao Rong LI Nan Bin CAO 《Journal of Mathematical Research with Applications》 CSCD 2012年第1期76-82,共7页
In virtue of the notion of likelihood ratio and moment generating function, the limit properties of the sequences of absolutely continuous random variables are studied, and a class of strong limit theorems represented... In virtue of the notion of likelihood ratio and moment generating function, the limit properties of the sequences of absolutely continuous random variables are studied, and a class of strong limit theorems represented by inequalities with random bounds are obtained. 展开更多
关键词 likelihood ratio strong limit theorem moment generating function.
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PADE APPROXIMANTS AS LIMITS OF RATIONAL FUNCTIONS OF BEST APPROXIMATION IN ORLICZ SPACE
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作者 Li Jialiang Central China Normal University, China Department of Mathematics Central Normal University 《Analysis in Theory and Applications》 1994年第2期74-82,共9页
In this paper, we prove that the best rational approximation of a given analytic function in Orlicz space L~*(G), where G = {|z|≤∈}, converges to the Pade approximants of the function as the measure of G approaches ... In this paper, we prove that the best rational approximation of a given analytic function in Orlicz space L~*(G), where G = {|z|≤∈}, converges to the Pade approximants of the function as the measure of G approaches zero. 展开更多
关键词 RATIONAL MATH PADE APPROXIMANTS AS limitS OF RATIONAL functionS OF BEST APPROXIMATION IN ORLICZ SPACE AS
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The Ill-Posedness of Derivative Interpolation and Regularized Derivative Interpolation for Non-Bandlimited Functions
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作者 Weidong Chen 《Applied Mathematics》 2022年第1期87-100,共14页
In this paper, the ill-posedness of derivative interpolation is discussed, and a regularized derivative interpolation for non-bandlimited signals is presented. The convergence of the regularized derivative interpolati... In this paper, the ill-posedness of derivative interpolation is discussed, and a regularized derivative interpolation for non-bandlimited signals is presented. The convergence of the regularized derivative interpolation is studied. The numerical results are given and compared with derivative interpolation using the Tikhonov regularization method. The regularized derivative interpolation in this paper is more accurate in computation. 展开更多
关键词 Nonband-limited function Derivative Interpolation ILL-POSEDNESS REGULARIZATION
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THE INTEGRAL AS A FUNCTION OF THE UPPER LIMIT AND AN ANALYTICAL SOLUTION TO PLANE STRAIN DRAWING AND EXTRUSION
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作者 赵德文 赵志业 张强 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1990年第8期759-765,共7页
A kinematically admissible velocity field which is different from Avitzur's is established in Cartesian Coordinates. An upper-bound analytical solution to strip drawing andextrusion is obtained by using the integr... A kinematically admissible velocity field which is different from Avitzur's is established in Cartesian Coordinates. An upper-bound analytical solution to strip drawing andextrusion is obtained by using the integral as a function of the upper limit in this paper. 展开更多
关键词 THE INTEGRAL AS A function OF THE UPPER limit AND AN ANALYTICAL SOLUTION TO PLANE STRAIN DRAWING AND EXTRUSION
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Right prefrontal cortex is activated for perceiving postural limits: a functional near-infrared spectroscopy study
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作者 Noriyuki Kamata Yoshimi Matsuo +2 位作者 Ayako Matsuya Satoru Inoue Kazuo Abe 《Health》 2009年第3期239-243,共5页
The purpose of this study was to investigate neuronal mechanisms active during the percep-tion of forward postural limits in a standing po-sition and to specify fall-related brain activity using optical functional nea... The purpose of this study was to investigate neuronal mechanisms active during the percep-tion of forward postural limits in a standing po-sition and to specify fall-related brain activity using optical functional near-infrared spectros-copy. The study group included six right-handed, healthy female volunteers (range: 19, 20 years). The optical imaging device comprised 16 opto-des designed to provide 24-channel recording of changes in hemoglobin oxygenation. We meas-ured the changes of oxygenated hemoglobin levels in the frontal region when subjects per-ceived reachability in a standing position. Com- pared with those in other regions, the oxygen-ated hemoglobin levels in the right frontal region compatible with the right prefrontal cortex sig-nificantly increased. This result suggests that brain activities in the right prefrontal cortex are related to perception of reachability. Overesti-mation of postural limits has been reported as one of the risk factor for falling. This overesti-mation might be induced by dysfunction in the prefrontal cortex, resulting in a failure to inhibit a motor program that would have caused a loss of balance in reaching. Activation of the right prefrontal cortex may be a key factor for pre-venting accidental falls in the elderly and in pa-tients with neurological disorders. 展开更多
关键词 POSTURAL limits FALLS functional NEAR-INFRARED Spectroscopy (fNIRS) PREFRONTAL CORTEX (PFC)
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Iterative and adjusting method for computing stream function and velocity potential in limited domains and convergence analysis
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作者 黎爱兵 张立凤 +1 位作者 臧增亮 张云 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2012年第6期687-700,共14页
The stream function and the velocity potential can be easily computed by solving the Poisson equations in a unique way for the global domain. Because of the var- ious assumptions for handling the boundary conditions, ... The stream function and the velocity potential can be easily computed by solving the Poisson equations in a unique way for the global domain. Because of the var- ious assumptions for handling the boundary conditions, the solution is not unique when a limited domain is concerned. Therefore, it is very important to reduce or eliminate the effects caused by the uncertain boundary condition. In this paper, an iterative and ad- justing method based on the Endlich iteration method is presented to compute the stream function and the velocity potential in limited domains. This method does not need an explicitly specifying boundary condition when used to obtain the effective solution, and it is proved to be successful in decomposing and reconstructing the horizontal wind field with very small errors. The convergence of the method depends on the relative value for the distances of grids in two different directions and the value of the adjusting factor. It is shown that applying the method in Arakawa grids and irregular domains can obtain the accurate vorticity and divergence and accurately decompose and reconstruct the original wind field. Hence, the iterative and adjusting method is accurate and reliable. 展开更多
关键词 limited domain stream function velocity potential iteration and adjust-ment CONVERGENCE
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基于障碍函数的PMSM阻尼可变性能增强滑模控制
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作者 杨荣荣 谭家昌 +3 位作者 张玲 黄华 张朋 王德义 《电机与控制学报》 北大核心 2026年第1期155-166,178,共13页
为了抑制抖振和增强永磁同步电机(PMSM)转速控制性能,提出一种基于障碍函数的永磁同步电机阻尼可变性能增强新型转速滑模控制方法。首先,设计一种非级联转速-电流一体化单环控制架构,该架构直接利用可测量转速和电流直接设计控制器,而... 为了抑制抖振和增强永磁同步电机(PMSM)转速控制性能,提出一种基于障碍函数的永磁同步电机阻尼可变性能增强新型转速滑模控制方法。首先,设计一种非级联转速-电流一体化单环控制架构,该架构直接利用可测量转速和电流直接设计控制器,而无需设计观测器估计角加速度。其次,引入障碍函数使sign切换函数的增益自适应调整,这不但极大削弱抖振,同时还解决电流无法自动受限的问题。此外,在滑模面设计中创新性地设计积分阻尼可变函数,有效地提升转速暂态控制性能。同时积分项使系统动态仅为滑动阶段,大大简化控制器和自适应律的设计复杂度。为了进一步增强鲁棒性,设计一种滤波扰动估计器对PMSM中的匹配和非匹配扰动同时进行估计并补偿。最后,通过实际实验对所提方法进行验证,实验结果表明该控制方法能够有效降低抖振和增强PMSM的转速控制性能。 展开更多
关键词 转速-电流一体化 障碍函数 自动受限 积分阻尼可变函数 滤波扰动估计器
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Inverse Limit of Spaces of Upper Semicontinuous Functions
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作者 张德学 《Northeastern Mathematical Journal》 CSCD 2001年第1期49-52,共4页
Given a compact Hausdorff space X, U(X) denotes the compact Hausdorff space of all the upper semicontinuous functions from X to the unit interval with the dual lim inf topology. Then U is an endofunctor o... Given a compact Hausdorff space X, U(X) denotes the compact Hausdorff space of all the upper semicontinuous functions from X to the unit interval with the dual lim inf topology. Then U is an endofunctor on compact Hausdorff space. It is proved in this note that this functor preserves inverse limits. 展开更多
关键词 upper semicontinuous function continuous lattice lim inf convergence inverse limit
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LIMITING WEAK-TYPE BEHAVIORS FOR CERTAIN LITTLEWOOD-PALEY FUNCTIONS 被引量:2
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作者 Xianming HOU Huoxiong WU 《Acta Mathematica Scientia》 SCIE CSCD 2019年第1期11-25,共15页
In this paper, we establish the following limiting weak-type behaviors of Littlewood-Paley g-function g_φ: for nonnegative function f∈ L^1(R^n),■and ■where f_t(x) =t^(-n)f(t^(-1) x) for t > 0. Meanwhile, the co... In this paper, we establish the following limiting weak-type behaviors of Littlewood-Paley g-function g_φ: for nonnegative function f∈ L^1(R^n),■and ■where f_t(x) =t^(-n)f(t^(-1) x) for t > 0. Meanwhile, the corresponding results for Marcinkiewicz integral and its fractional version with kernels satisfying L_α~q-Dini condition are also given. 展开更多
关键词 limitING BEHAVIORS weak-type bounds LITTLEWOOD-PALEY g-functions Marcinkiewicz integrals L_α~q -Dini conditions
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Effect of Intermittent Pneumatic Compression on Functional Level and Quality of Life in Community-Dwelling Older Adults with Limited Ambulation Due to Leg Pain: A Randomized Controlled Trial
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作者 Weerasinghe Mudiyanselage Sujeewa Weerasinghe Thunpaththu Mudiyanselage Upul Sanjeewa Thunpaththu +4 位作者 Weerasinghe Mudiyanselage Sandali Anjana Weerasinghe Weerasinghe Mudiyanselage Shalindu Thushen Weerasinghe Pahala Walpola Gamarallage Shirani Walpola Dissanayaka Mudiyanselage Tharanga Padmini Dissanayaka Angelo Karunaratne 《Health》 2021年第10期1145-1169,共25页
Background and Purpose: Walking difficulties are defined as any reduction in speed, balance, or change of gait, causing limited ambulation. These difficulties are a common problem in older adults and may greatly affec... Background and Purpose: Walking difficulties are defined as any reduction in speed, balance, or change of gait, causing limited ambulation. These difficulties are a common problem in older adults and may greatly affect their quality of life (QOL) and restrict their personal independence and participation. This study aimed to determine the effect of intermittent pneumatic compression (IPC) on lower leg pain, walking capacity, functional mobility, ankle range of motion (AROM), and QOL of community-dwelling older people with walking difficulties. Methods: In this randomized controlled trial, 34 eligible participants with self-reported lower limb pain and limited ambulation were randomized either to the intermittent pneumatic compression intervention group (IPCIG) or static compression control group (SCCG). The IPCIG and SCCG were trained to receive IPC and SC respectively for both lower legs and instructed to continue the application independently at home for 15 minutes per session, 2 sessions a day, 7 days per week for 4 weeks independently at the home. Outcome measures of lower leg pain, AROM, walking capacity, and functional mobility were assessed at baseline and at the first, second, third, and fourth weeks after randomization. Quality of life was assessed at baseline and immediately after the intervention. Results and Discussion: IPCIG showed a more significant improvement compared to the SCCG at the post-interventional stage for QOL and all the subscales. The findings show that “80% improved QOL” is 53% higher with the application of IPC than with SC for 4 weeks. The IPCIG showed a more significant improvement in the 6-minute walk test (6 MWT) at the third and fourth weeks compared to the SCCG. A pairwise comparison of mean values of 6 MWT over 4 weeks within the IPCIG showed a significant difference between all the weeks. Pairwise comparisons between groups at each time point showed that the IPCIG showed a more significant improvement in the timed up and go (TUG) test at the third and fourth weeks compared to the SCCG. Pairwise comparison of mean values of TUG test within the IPCIG showed a significant difference over 4 weeks, except between the second and third weeks, fourth week, and third and fourth weeks. The IPCIG showed a more significant improvement in lower leg pain between all weeks except the first week compared to the SCCG. Pairwise comparison of mean values of lower leg pain over 4 weeks within the IPCIG showed a significant difference among all weekly outcomes except between 1 and 2 weeks. The IPCIG showed a more significant improvement in left and right ankle dorsiflexion ROM at the third and fourth weeks compared to the SCCG. Conclusions: The IPC was effective in reducing lower leg pain and increasing the AROM and improving the walking capacity, functional mobility level, and QOL of community-dwelling older people with walking disabilities. Walking disability in old age is a common condition requiring physical therapy. Intermittent pneumatic compression can be used as a physical therapy modality for this patient group. 展开更多
关键词 Intermittent Pneumatic Compression functional Level Quality of Life Older Adults limited Ambulation Leg Pain
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论义务性法律规范的概念
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作者 王夏昊 《现代法学》 北大核心 2026年第1期135-157,共23页
义务性法律规范是和允许性法律规范、授权性法律规范相区分的一种法律规范。它的逻辑算子包括“命令”和“禁止”,并且这两者是可以相互定义的,因此可以被归为和“允许”相对立的一种算子。特定国家的法律文本可以用不同的语言来表达这... 义务性法律规范是和允许性法律规范、授权性法律规范相区分的一种法律规范。它的逻辑算子包括“命令”和“禁止”,并且这两者是可以相互定义的,因此可以被归为和“允许”相对立的一种算子。特定国家的法律文本可以用不同的语言来表达这种逻辑算子。作为一种命令的义务性法律规范意味着:它们的权威意图它们的承受者用他的意志来代替承受者的意志作为承受者做行为的决定,并且用他的意志来代替承受者自己对做或不做行为进行慎思或推理。因此,规范权威就会对那些违反了义务性法律规范的行为规定一定的法律制裁。这就意味着对一定行为规定了法律制裁的法律条文所表达的也是一种义务性法律规范。相反,从命令的接收者即规范的承受者的角度看,义务性法律规范是它们的承受者在它们可适用情形下做或不做它们所规定的行为的一种不容置辩的独立于内容的理由,不是一种定效理由而是一种起效理由,是一种排他性理由。无论从规范权威的角度还是从规范的承受者的角度看,义务性法律规范所调整的行为或社会关系都是受限制的,也就是说,法律权威只能就一些人们的行为或社会关系来规定义务性法律规范,除此之外,不能或不应该规定义务性法律规范。 展开更多
关键词 义务性法律规范 命令 行为理由 作用的局限性
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巧用Stirling公式证明中心极限定理
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作者 梁静 《高等数学研究》 2026年第1期38-41,共4页
文章巧用Stirling公式给出De Moivre-Laplace中心极限定理的经典证明,进一步利用Fourier变换,给出了一般独立同分布随机变量的中心极限定理的证明.
关键词 中心极限定理 二项分布 STIRLING公式 特征函数
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叶黄素在保健食品中的合规性应用与递送系统研究进展
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作者 段昊 刘嘉琪 +7 位作者 任祥瑞 松伟 张绍时 包书源 常新悦 李璐 王利 闫文杰 《食品科学》 北大核心 2026年第2期366-375,共10页
叶黄素作为着色剂被用于各类食品中,因其功能性较为突出,也被用于保健食品、药品中。叶黄素具有缓解视觉疲劳、抗氧化、促进脑部神经系统发育等多种保健功效,其作为保健食品原料应用时,对于剂量的设计需考虑其起效剂量与安全性剂量。然... 叶黄素作为着色剂被用于各类食品中,因其功能性较为突出,也被用于保健食品、药品中。叶黄素具有缓解视觉疲劳、抗氧化、促进脑部神经系统发育等多种保健功效,其作为保健食品原料应用时,对于剂量的设计需考虑其起效剂量与安全性剂量。然而,叶黄素作为保健食品的功能性原料使用时,其使用量没有国家标准可供参考。基于此,本文统计并分析了叶黄素在我国保健食品中的应用现状、合规性使用依据、功能作用机制研究进展;综述了国内外8个国家及地区对于叶黄素的使用依据与限量;并详细论述了叶黄素高效利用的递送系统研究进展,以期为叶黄素在我国保健食品中的研究开发和应用提供一定的参考及依据。 展开更多
关键词 叶黄素 国内外法规限量 功能性 安全性 递送系统 保健食品
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污染遗留效应改变土壤生态功能对于水分限制的响应
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作者 张文 文书海 +2 位作者 郑静梅 冯娇 刘玉荣 《环境科学》 北大核心 2026年第1期614-621,共8页
长期环境污染可能会对土壤微生物群落及其维持的生态功能产生遗留效应.在全球变化的背景下,污染地区可能会同时经历其他环境压力因素(如水分限制);尽管大量研究探讨了水分限制对微生物群落及其多功能的影响,但长期污染遗留效应如何影响... 长期环境污染可能会对土壤微生物群落及其维持的生态功能产生遗留效应.在全球变化的背景下,污染地区可能会同时经历其他环境压力因素(如水分限制);尽管大量研究探讨了水分限制对微生物群落及其多功能的影响,但长期污染遗留效应如何影响土壤生态功能对于水分限制的响应仍不明确.采集了600多a重金属污染历史矿区农田土壤样品,通过室内水分梯度培养实验,结合功能指标测定和扩增子测序技术,探究了污染遗留效应下微生物及其介导的生态功能对于水分限制的响应.结果表明,与对照土壤相比,污染土壤的微生物呼吸、碳利用效率和多重功能性在水分限制下均显著降低.污染土壤的多重功能性与土壤水分之间存在显著的正相关关系,且污染土壤的整体功能稳定性高于对照土壤.进一步层次分析表明,污染土壤的多重功能性主要受到土壤水分、微生物生物量碳和生物量磷的共同影响,且这三者与多重功能性之间呈显著正相关.此外,污染遗留效应削弱了细菌多样性对于水分限制的抵抗力,并改变了微生物群落结构.总之,污染遗留效应削弱了细菌群落和土壤功能(微生物呼吸、碳利用效率和多重功能性)对于水分限制的抵抗力,但污染土壤的整体功能稳定性较高,研究结果可为评估污染地区土壤生态功能如何响应潜在水分限制提供重要依据. 展开更多
关键词 污染遗留效应 水分限制 微生物 生态功能 功能稳定性
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发展壮大农村集体经济的实践困境与转型路径
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作者 马彦丽 孙玉竹 曹斌 《经济与管理》 北大核心 2026年第2期21-27,共7页
发展壮大农村集体经济是实现乡村振兴的重要抓手,但在实践中面临诸多困境。基于农村集体经济组织应当定位于资源资产的“经营者”还是“管理者”这一核心问题,系统剖析其治理缺陷与组织优势,并据此明确其适宜的功能定位。研究发现,农村... 发展壮大农村集体经济是实现乡村振兴的重要抓手,但在实践中面临诸多困境。基于农村集体经济组织应当定位于资源资产的“经营者”还是“管理者”这一核心问题,系统剖析其治理缺陷与组织优势,并据此明确其适宜的功能定位。研究发现,农村集体经济组织因其追求多重目标导致的预算软约束,内部治理与外部约束机制不健全,以及不适用破产法导致市场竞争能力受限等治理缺陷,制约了其作为直接经营者的效率。不过,农村集体经济组织在降低资源整合的交易成本、高效承接与落地政府支农项目并增强项目普惠性等方面具有显著的组织优势。因此,农村集体经济组织应扬长避短,将其核心经济功能从直接参与市场竞争的“经营者”,调整为专注于集体资源资产整合、发包、维护与政策承接的“管理者”。通过强化资源管理能力、优化政策项目对接等举措,推动农村集体经济组织健康可持续发展。 展开更多
关键词 农村集体经济组织 治理局限 组织优势 功能定位
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基于四阶矩法的桥梁船撞易损性分析方法及应用
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作者 颜海泉 宋彦臣 王君杰 《公路交通技术》 2026年第1期135-145,共11页
桥梁船撞易损性分析是基于性能的桥梁船撞设计方法的重要内容,针对目前桥梁船撞易损性计算理论尚未系统建立的问题,提出了桥梁船撞易损性的定义及其计算公式,并建立了船舶撞击下桥梁结构体系的极限状态功能函数;考虑船撞作用的水位、船... 桥梁船撞易损性分析是基于性能的桥梁船撞设计方法的重要内容,针对目前桥梁船撞易损性计算理论尚未系统建立的问题,提出了桥梁船撞易损性的定义及其计算公式,并建立了船舶撞击下桥梁结构体系的极限状态功能函数;考虑船撞作用的水位、船舶吨位、偏航角随机性,以及结构参数的随机性参数,构建了桥梁船撞性能失效全概率计算的总体样本空间,提出了基于四阶矩法的桥梁结构船撞极限状态功能函数失效概率的计算方法,建立了桥梁船撞易损性分析计算流程。分析结果表明:1)四阶矩法能高效计算桥梁船撞功能函数失效概率,船舶撞击作用下桥梁轻微损伤失效概率呈阶跃型,中等损伤、严重损伤以及倒塌破坏失效概率呈S型;2)分析结果能准确表征钢筋屈服、混凝土压溃、钢筋弹塑性变形对桥梁船撞易损性的影响规律。本文提出的桥梁船撞易损性计算公式与求解方法可为基于性能的桥梁船撞设计理论与应用提供重要参考。 展开更多
关键词 船-桥碰撞 基于性能设计 性能指标 易损性分析 极限状态功能函数
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