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间歇性泄洪对鱼类躲避TDG过饱和胁迫空间的影响研究

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水电能源科学 2025年第2期43卷 78-83页

作者：王莉唐琦冀前锋梁瑞峰李克锋中国电建集团成都勘测设计研究院有限公司四川成都611130 四川水发勘测设计研究有限公司四川成都610072 长江水资源保护科学研究所湖北武汉430051 四川大学山区河流保护与治理全国重点实验室四川成都610065

高坝泄洪造成的总溶解气体(TDG)过饱和威胁河道生态安全,目前尚无较好的解决方法。因此,采用平面二维数值模型,针对日调节水库运行特征,研究了不同间歇性泄洪工况下的TDG饱和度分布。结合鱼类对TDG饱和度的耐受能力,分析了间歇性泄洪工... 详细信息

高坝泄洪造成的总溶解气体(TDG)过饱和威胁河道生态安全,目前尚无较好的解决方法。因此,采用平面二维数值模型,针对日调节水库运行特征,研究了不同间歇性泄洪工况下的TDG饱和度分布。结合鱼类对TDG饱和度的耐受能力,分析了间歇性泄洪工况下可供鱼类躲避区域面积的变化规律。结果表明,在等时段间歇性泄洪模式下,随着间歇时间增加,鱼类可躲避区域面积平均值逐渐增加,但可躲避区域面积最小值随间歇时间增加先减小后增大;在不等时段间歇性泄洪模式下,提高间歇时间与泄洪时间之比将增加鱼类可躲避区域面积,降低可躲避区域面积最小值。研究结果可为高坝工程制定生态调度提供方法参考,对维护河流生态安全具有一定的生态意义。

关键词：调度方案数值模拟 TDG过饱和可躲避区域间歇性泄洪

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Column envelope meshing pair and its design method for single screw compressors

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第1期10卷 31-36页

作者： Wei-feng WU Quan-ke feng School of Energy and Power Engineering Xi 'an Jiaotong University Xi 'an 710049 China

A single screw compressor (SSC) is an important component found in many refrigeration ***,the durability is not so good because of the friction between its meshing *** the column envelope meshing pair was pro-posed to prolong the operating life of SSCs,although it has not been applied to commercial refrigeration *** accelerate the industrial application,a mathematical model for analyzing the column envelope meshing pair is established based on the geometry and *** giving the flanks of column envelope grooves are obtained,and teeth flank meshing with the groove is *** show that this model could be applicable in the design of the column envelope type SSC.

关键词： Column envelope Single screw compressor (SSC) Meshing pair design Mathematical model

The partial C^(0)-estimate along a general continuity path and applications

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Science China Mathematics 2021年第11期64卷 2495-2520页

作者： ke feng Liangming Shen School of Mathematical Sciences University of Electronic Science and Technology of ChinaChengdu 611731China School of Mathematical Sciences Beihang UniversityBeijing 100191China

We establish a new partial C^(0)-estimate along a continuity path mixed with conic singularities along a simple normal crossing divisor and a positive twisted(1,1)-form on Fano *** an application,this estimate enables us to show the reductivity of the automorphism group of the limit space,which leads to a new proof of the Yau-Tian-Donaldson conjecture.

关键词： partial C0-estimate K?hler-Einstein metric conic K?hler metric

基于RBF神经网络的防空导弹武器系统作战效能评估

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系统仿真学报 2025年第2期37卷 529-540页

作者：张鹏冯柯宫建成杨小强申金星陆军工程大学野战工程学院江苏南京210000

针对防空导弹武器系统作战效能指标维度高、复杂性强以及评估方法主观等问题,提出基于RBF神经网络的作战效能评估方法。通过分析OODA环作战理论,构建了防空导弹武器系统作战效能指标体系。通过MATLAB实现RBF神经网络模型仿真,并应用BP、... 详细信息

针对防空导弹武器系统作战效能指标维度高、复杂性强以及评估方法主观等问题,提出基于RBF神经网络的作战效能评估方法。通过分析OODA环作战理论,构建了防空导弹武器系统作战效能指标体系。通过MATLAB实现RBF神经网络模型仿真,并应用BP、PCA-BP、Elman神经网络等多种方法进行对比仿真验证。仿真结果表明:RBF神经网络模型预测评估结果与真实值更为接近,充分证明了该模型在防空导弹武器系统作战效能评估中的有效性,为指挥员作战决策提供有力支持。

关键词： RBF神经网络防空导弹武器系统效能评估作战仿真 OODA环

Novel algorithm for complex bit reversal:employing vector permutation and branch reduction methods

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第10期10卷 1492-1499页

作者： feng YU Ze-ke WANG Rui-feng GE Department of lnstrument Engineering Zhejiang University Hangzhou 310027 China

We present novel vector permutation and branch reduction methods to minimize the number of execution cycles for bit reversal *** new methods are applied to single instruction multiple data(SIMD) parallel implementation of complex data floating-point fast Fourier transform(FFT).The number of operational clock cycles can be reduced by an average factor of 3.5 by using our vector permutation methods and by 1.1 by using our branch reduction methods,compared with conventional *** on MPC7448(a well-known SIMD reduced instruction set computing processor) demonstrate that our optimal bit-reversal algorithm consistently takes fewer than two cycles per element in complex array operations.

关键词： Bit reversal Vector permutation Branch reduction Single instruction multiple data (SIMD) Fast Fourier transform (FFT)

Modular Invariance and Anomaly Cancellation Formulas in Odd Dimension Ⅱ

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Acta Mathematica Sinica,English Series 2017年第4期33卷 455-469页

作者： ke feng LIU Yong WANG Center of Mathematical Sciences Zhejiang UniversityHangzhou 310027P.R.China Department of Mathematics University of California at Los AngelesLos Angeles CA90095-1555USA School of Mathematics and Statistics Northeast Normal UniversityChangchun 130024P.R.China

By studying modular invariance properties of some characteristic forms, we get some generalized anomaly cancellation formulas on(4 r-1)-dimensional manifolds with no assumption that the 3 rd de-Rham cohomology of manifolds vanishes. These anomaly cancellation formulas generalize our previous anomaly cancellation formulas on(4 r-1)-dimensional manifolds. We also generalize our previous anomaly cancellation formulas on(4 r-1)-dimensional manifolds and the Han–Yu rigidity theorem to the(a, b) case.

关键词： Modular invariance Eisenstein series generalized cancellation formulas in odd dimension Witten rigidity theorem

New Results on Nonexistence of Perfect p-Ary Sequences and Almost p-Ary Sequences

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Acta Mathematica Sinica,English Series 2016年第1期32卷 2-10页

作者： Hai Ying LIU ke Qin feng School of Mathematical Sciences Peking University Department of Mathematical Sciences Tsinghua University

Complex periodical sequences with lower antocorrelation values are used in CDMA comnmnieation systems and cryptography. In this paper we present new nonexistence results on perfect p-ary sequences and almost p-ary seq... 详细信息

关键词： Perfect sequence p-ary and almost p-ary sequence difference set cyclotomic field imag-inary quadratic field

Minimal Complex Surfaces with Levi–Civita Ricci-flat Metrics

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Acta Mathematica Sinica,English Series 2018年第8期34卷 1195-1207页

作者： ke feng LIU Xiao Kui YANG Department of Mathematics Capital Normal University Beijing 100048 P. R. ChinaDepartment of Mathematics University of California at Los Angeles California 90095 USA Morningside Center of Mathematics Institute of Mathematics Hua Loo-Keng center of Mathematical Sciences Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 P. R. China

This is a continuation of our previous paper [14]. In [14], we introduced the first Aeppli- Chern class on compact complex manifolds, and proved that the （1, 1） curvature form of the Levi-Civita connection represents the first Aeppli-Chern class which is a natural link between Riemannian geometry and complex geometry. In this paper, we study the geometry of compact complex manifolds with Levi- Civita Ricci-flat metrics and classify minimal complex surfaces with Levi-Civita Ricci-flat metrics. More precisely, we show that minimal complex surfaces admitting Levi-Civita Ricci-flat metrics are K/ihler Calabi-Yau surfaces and Hopf surfaces.

关键词： Levi-Civita Ricci-flat metric kodaira dimension classication

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数字化转型与企业碳减排

安徽师范大学学报(社会科学版) 2025年第1期53卷 85-99页

作者：何理甄皓晴冯科中国社会科学院大学应用经济学院北京102488 北京大学经济学院北京100871

随着气候异常问题日益严峻,减少碳排放已成为全球共识。数字经济作为一种新兴的经济形态,以其高效、智能、创新的特点,正成为推动碳减排的重要力量。本研究基于2011—2021年上市公司数据,从微观企业视角探究了数字化转型对企业碳减排的... 详细信息

随着气候异常问题日益严峻,减少碳排放已成为全球共识。数字经济作为一种新兴的经济形态,以其高效、智能、创新的特点,正成为推动碳减排的重要力量。本研究基于2011—2021年上市公司数据,从微观企业视角探究了数字化转型对企业碳减排的影响及其具体作用机制。研究结果发现:(1)数字化转型能够显著促进我国企业的碳减排效果,该结论在经过多种稳健性检验后依然成立。(2)企业碳减排信息披露强化了数字化转型的碳减排作用。(3)数字化转型可以通过提升技术创新和提高企业社会关注度,进而促进碳减排。(4)对于环境规制强度越高、市场竞争越激烈、资本密集程度越高的企业而言,其数字化转型对碳减排的影响越显著。本研究揭示了企业数字化转型影响碳减排的具体作用机制,为后续的微观企业研究奠定了基础,也为企业数字化转型与碳减排的协调发展提供了理论支持和实践借鉴。

关键词：数字化转型企业碳减排 “双碳”目标技术创新社会关注度