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铁路工程造价“营改增”影响分析

交通企业管理 2025年第1期40卷 52-54页

作者：田泽仁中国铁建大桥工程局集团有限公司

自2016年4月起,我国开始实施“营改增”税制改革,将原有的增值税和营业税合并为一种税种。这一改革旨在促进国民经济发展,优化税制结构,减轻企业负担,提高税收透明度等。然而,“营改增”对于铁路工程建设所产生的影响却备受关注。铁路... 详细信息

自2016年4月起,我国开始实施“营改增”税制改革,将原有的增值税和营业税合并为一种税种。这一改革旨在促进国民经济发展,优化税制结构,减轻企业负担,提高税收透明度等。然而,“营改增”对于铁路工程建设所产生的影响却备受关注。铁路工程建设是我国基础设施建设的重要领域之一,对国民经济的发展起着至关重要的作用。由于铁路工程建设所需资金巨大、工程周期长、风险高等特点.

关键词：铁路工程 “营改增” 工程造价税收政策会记核算企业创新

Dalea:A Persistent Multi-Level Extendible Hashing with Improved Tail Performance

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Journal of Computer Science & Technology 2023年第5期38卷 1051-1073页

作者：熊子威蒋德钧熊劲 ren ren Center for Advanced Computer Systems Institute of Computing TechnologyChinese Academy of Sciences Beijing 100190China University of Chinese Academy of Sciences Beijing 101408China Huawei Technology Co. Ltd.Shanghai 201206China

Persistent memory(PM)promises byte-addressability,large capacity,and *** memory systems,such as key-value stores and in-memory databases,benefit from such features of *** to the great popularity of hash-ing index in main memory systems,a number of research efforts are made to provide high average performance persistent ***,suboptimal tail performance in terms of tail throughput and tail latency is still observed for existing persistent *** this paper,we analyze major sources of suboptimal tail performance from key design issues of persis-tent *** identify the global hash structure and concurrency control as remaining explorable design spaces for im-proving tail *** propose Directory-sharing Multi-level Extendible Hashing(Dalea)for *** designs an-cestor link-based extendible hashing as well as fine-grained transient lock to address the two main sources(rehashing and locking)affecting tail *** evaluation results show that,compared with state-of-the-art persistent hashing Dash,Dalea achieves increased tail throughput by 4.1x and reduced tail latency by ***,in order to provide de-sign guidelines for improving tail performance,we adopt Dalea as a testbed to identify different impacts of four factors on tail performance,including fine-grained rehashing,transient locking,memory pre-allocation,and fingerprinting.

关键词： persistent memory persistent hashing indexing structure

In situ observation of the dissolution kinetics of Al_(2)O_(3) particles in CaO–Al_(2)O_(3)–SiO_(2) slags using laser confocal scanning microscopy

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International Journal of Minerals,Metallurgy and Materials 2023年第2期30卷 345-353页

作者： Changyu ren Caide Huang Lifeng Zhang Ying ren School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004China Shougang Jingtang United Iron and Steel Co. Ltd.Tangshan 063200China School of Mechanical and Materials Engineering North China University of TechnologyBeijing 100144China

The dissolution kinetics of Al_(2)O_(3) in CaO-Al_(2)O_(3) SiOslags was studied using a high-temperature confocal scanning laser microscope at 1773 to 1873 *** results show that the controlling step during the Al_(2)O_(3) dissolution was the diffusionin molten *** was found that the dissolution curves of Al_(2)O_(3) particles were hardly agreed with the traditional boundary layer diffusion model with the increase of the CaO/Al_(2)O_(3) ratio of slag.A modified diffusion equation considering slag viscosity was developed to study the dissolution mechanism of Al_(2)O_(3) in *** coefficients of Al_(2)O_(3) in slag were calculated as 2.8×10to 4.1×10m~2/s at the temperature of 1773-1873 *** dissolution rate of Al_(2)O_(3) increased with higher temperature,CaO/Al_(2)O_(3),and particle size.A new model was shown to be v_(Al_(2)O_(3))=0.16×r_(0)^(1.58)×x^(3.52)×(T-T_(mp))^(1.11)to predict the dissolution rate and the total dissolution time of Al_(2)O_(3) inclusions with various sizes,where vAl_(2)O_(3) is the dissolution rate of Al_(2)O_(3) in volume,μm^(3)/s;x is the value of CaO/Al_(2)O_(3) mass ratio;R_(0) is the initial radius of Al_(2)O_(3),μm;T is the temperature,K;T_(mp) is the melting point of slag,K.

关键词： inclusion dissolution kinetics confocal scanning laser microscope refining slag

Dynamic crossover in [VIO^(2+)][Tf_(2)N-]_(2) ionic liquid

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Chinese Physics B 2021年第1期30卷 374-379页

作者： Gan ren Departments of Physics&Key Laboratory of Photonic and Optical Detection in Civil Aviation Civil Aviation Flight University of ChinaGuanghan 618307China

Ionic liquids usually behave as fragile liquids,and the temperature dependence of their dynamic properties obeys supper-Arrhenius *** this work,a dynamic crossover is observed in([VIO^(2+)][Tf_(2)N-]_(2)) ionic liquid at the temperature of 240-800 *** diffusion coefficient does not obey a single Arrhenius law or a Vogel-Fulcher-Tammann(VFT) relation,but can be well fitted by three Arrhenius laws or a combination of a VFT relation and an Arrhenius *** origin of the dynamic crossover is analyzed from correlation,structure,and *** gets a stronger backward correlation at a lower temperature,as shown by the fractal dimension of the random *** temperature dependence function of fractal dimension,heterogeneity order parameter,and thermodynamic data can be separated into three regions similar to that observed in the diffusion *** two crossover temperatures observed in the three types of data are almost the same as that in diffusion coefficient fitted by three Arrhenius *** results indicate that the dynamic crossover of[VIO2+][Tf2 N-]2 is attributed to the heterogeneous structure when it undergoes cooling.

关键词： ionic liquids dynamic crossover heterogeneity order parameter fractal dimension fragile

Bioinspired soft actuators with highly ordered skeletal muscle structures

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Bio-Design and Manufacturing 2022年第1期5卷 174-188页

作者： Yingjie Wang Chunbao Liu Luquan ren Lei ren School of Mechanical and Aerospace Engineering Jilin UniversityChangchun 130022China School of Mechanical Aerospace and Civil EngineeringUniversity of ManchesterManchester M139PLUK Key Laboratory of Bionic Engineering Ministry of EducationJilin UniversityChangchun 130022China

Mammals such as humans develop skeletal muscles composed of muscle fibers and connective tissue,which have mechanical properties that enable power output with three-dimensional motion when *** muscle-like actuators developed to date,such as the McKibben artificial muscle,often focus sole contractile elements and have rarely addressed the contribution of flexible connective tissue that forms an integral part of the structure and morphology of biological ***,we present a class of pneumatic muscle-like actuators,termed highly mimetic skeletal muscle(HimiSK)actuator,that consist of parallelly arranged contractile units in a flexible matrix inspired by ultrasonic measurements on skeletal *** contractile units act as a muscle fiber to produce active shortening force,and the flexible matrix functions as connective tissue to generate passive *** application of positive pressure to the contractile units can produce a linear contraction and *** this actuator,we assign different flexible materials as contractile units and a flexible matrix,thus forming five mold *** actuators feature three-dimensional motion on activation and present both intrinsic force-velocity and force-length characteristics that closely resebmle those of a biological *** output and tetanic force produced by harder contractile units improve the maximum output force by up to about 41.3%and the tetanic force by up to about 168%.Moreover,high displacement and velocity can be generated by a softer flexible matrix,with the improvement of maximum displacement up to about 33.3%and velocity up to about 73%.The results demonstrate that contractile units play a crucial role in force generation,while the flexible matrix has a significant impact on force transmission and deformation;the final force,velocity,displacement,and three-dimensional motion results from the interplay of contractile units,fluid and flexible *** approach introduces a m

关键词： Bioinspired Soft robotics Actuator Skeletal muscle

Load-dependent Variable Gearing Mechanism of Muscle-like Soft Actuator

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Journal of Bionic Engineering 2022年第1期19卷 29-43页

作者： Yingjie Wang Chunbao Liu Luquan ren Lei ren School of Mechanical and Aerospace Engineering Jilin UniversityChangchun130022China Key Laboratory of Bionic Engineering Ministry of EducationJilin UniversityChangchun130022China School of Mechanical Aerospace and Civil EngineeringUniversity of ManchesterManchesterM139PLUK

Pennate muscle is characterized by muscle fibers that are oriented at a certain angle(pennation angle)relative to the muscle’s line of action and rotation during *** fiber rotation amplifies the shortening velocity of muscle,to match loading conditions without any control *** unique variable gearing mechanism,which characterized by Architecture Gear Ratio(AGR),is involves complex interaction among three key elements:muscle fibers,connective tissue,and the pennation ***,how three elements determine the AGR of muscle-like actuator is still *** study introduces a Himisk actuator that arranges five contractile units at a certain pennation angle in a flexible matrix,the experiment and simulation results demonstrated that the proposed actuator could vary AGR automatically in response to variable loading *** on this actuator,we present a series of actuators by simulations with the varying pennation angle(P),elastic modulus of the flexible matrix(E),and number of contractile units(N)to analyze their effects on AGR,and their interaction by three-factor analysis of *** results demonstrated that P and N effect on the AGR significantly,while E effects on AGR slightly,which supported the idea that the P is the essential factor for the AGR,and N is also an important factor due to the capability of force *** provides a better understanding of mechanical behavior and an effective optimizing strategy to muscle-like soft actuator.

关键词： Bioinspired Actuator Pennate muscle Gearing mechanism

From Elastic Spin to Phonon Spin:Symmetry and Fundamental Relations

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Chinese Physics Letters 2022年第12期39卷 41-49页

作者： Jie ren Center for Phononics and Thermal Energy Science China-EU Joint Lab on NanophononicsShanghai Key Laboratory of Special Artificial Microstructure Materials and TechnologySchool of Physics Science and EngineeringTongji UniversityShanghai 200092China

This work is mainly based on postgraduate lectures at Tongji University since 2020 *** firstly revisit the elastic spin and orbital angular momentum[*** 115,9951(2018)]but more general for anisotropic systems by applying Noether’s theorem to the elastic Lagrangian and by applying the symmetry argument in the field ***,fundamental relations between elastic energy flux and elastic spin are *** particular cases,the wave spin is closely related to the vorticity of energy flux and ***,we move forward from the elastic spin to revisit the phonon spin[Fizika Tverdogo Tela 3,2160(1961)]by applying the second quantization to elastic *** show that the uncovered phonon spin,a polarized elastic-vibration quanta,is generally not restricted to transverse phonon modes,but applying to general phonon modes,such as the longitudinal phonon modes,surface phonon modes,and hybridized phonon modes,regarded as a consequence of mode *** elastic spin and phonon spin originate from the local rotating of the field polarization in time domain,not the local circulation(vorticity)of displacement or velocity in space *** is hopeful that the present results could advance the fundamental understanding of phonon spin and elastic spin,and promote the spin phononics for hybrid quantum sensing and technology with multiple degrees of freedom.

关键词： theory phonon applying

Discrete Differential Calculus on Simplicial Complexes and Constrained Homology

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Chinese Annals of Mathematics,Series B 2023年第4期44卷 615-640页

作者： Shiquan ren School of Mathematics and Statistics Henan University

Let V be a finite *** K be a simplicial complex with its vertices in *** this paper,the author discusses some differential calculus on *** constructs some constrained homology groups of K by using the differential calculus on ***,he defines an independence hyper graph to be the complement of a simplicial complex in the complete hypergraph on *** L be an independence hypergraph with its vertices in *** constructs some constrained cohomology groups of L by using the differential calculus on V.

关键词： Simplicial complexes Hypergraphs Chain complexes Homology Differential calculus

New advances in biomimetic surface

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Science China(Technological Sciences) 2016年第10期59卷 1619-1620页

作者： ren LuQuan Key Laboratory of Bionic Engineering Ministry of Education Jilin University

Anti-adhesion is a common phenomenon in living organisms, which is the evolution results to adapt their living surroundings. From the perspective of surface type, there are two typical anti-adhesion mechanisms： micro- and nano- surface structures and liquid-covered surface. Many living organisms possess one or two of these anti-adhesion surfac- es in order to achieve superior anti-adhesion, for example, soil animals like mole cricket and earthworm [1]. Carnivo- rous pitcher plant Nepenthes can capture and digest insects to meet the fundamental nutrients needs. When the insects crawl on its slippery peristome, they could easy-sliding into the picher, known as ＂aquaplaning＂. Wong et al. [2] at Harvard University has designed and fabricated slippery surface mimicking this slippery mechanism in Nepenthes, the results of which was published in Nature. However, questions remain about the mechanism underlying its func- tion, especially for the liquid film formation mechanism.

关键词： Biomimetics Hydrophilicity