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Campus Bus Network Design and Evaluation Based on the Route Property

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Tsinghua Science and Technology 2017年第5期22卷 539-550页

作者： Jishiyu Ding Shuo feng li li yi Zhang the Department of Automation Tsinghua University

A campus bus network design and evaluation, taking Tsinghua University as an example, is investigated in this paper. To minimize the total cost for both passengers and operator, the campus bus system planning in a sequential approach is discussed, including the route network design, headway （i.e., the inverse of service frequency） optimization, and system evaluation. The improved genetic algorithm is proposed to optimize the route network based on the route property, and the impacts of the fluctuation of passenger demand and average traveling time are analyzed. The identity proportion in the headway optimization is then introduced with full consideration of its impacts. Based on the actual variety of passenger demand, a non-fixed schedule demonstrates its efficiency. VISSIM is finally adopted to simulate the campus bus system and a comprehensive evaluation system for the campus bus is developed. Compared with the current bus network and the one without considering the route property, the evaluation of the proposed approach shows an improvement of 18.7% and 10.1%, respectively. Moreover, the sequential approach shows an efficiency significance for the development of public transit systems passengers and operator. mprovement over the alternative method. It is of great n large industrial parks to decrease the total cost for both

关键词： genetic algorithm transit network design route property identity proportion transit system evaluation

Formation mechanism and mechanical properties of surface nanocrystallized Ti-6Al-4V alloy processed by surface mechanical attrition treatment

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Rare Metals 2023年第4期42卷 1343-1352页

作者： yi-feng li Cheng Chen J.Ranabhat yi-Fu Shen College of Materials Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing210016China

In the present work,surface mechanical attrition treatment(SMAT)was proposed to achieve surface nanocrystallization on Ti-6Al-4V surface via high-energy planetary ball milling method using a planetary ball *** characteristics of microstructure were studied using different *** nanocrystallization is achieved on Ti-6Al-4V *** process of refinement could be summarized into four *** the refinement process,the reticular continuous beta phase performs a significant role,it cracked,broke up and moved to each side along the grain *** movement of beta grains has the capabilities of effectively optimizing the grain orientation and accelerating the further refinement of alpha *** also plays an important role during the *** grain orientation between different types of grains seems to be larger than that of same type *** interface will be divided into smaller nanocrystalline grains once the dislocation density breaks the ***,the balance will be achieved again and owns a higher critical value which cannot be broken,then a stable grain size can be achieved *** results of microhardness,friction coefficient and wear mass loss tests of SMAT samples indicate that the mechanical behaviors of substrate are greatly enhanced after this novel SMAT treatment.

关键词： Surface nanocrystallization Dual-phase titanium alloy SMAT Mechanical properties

Manipulation of acoustic wavefront by transmissive metasurface based on pentamode metamaterials

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Chinese Physics B 2019年第2期28卷 306-312页

作者： ying liu yi-feng li Xiao-Zhou liu College of Computer Science and Technology Nanjing Tech University Key Laboratory of Modern Acoustics Ministry of EducationNanjing University Key Laboratory of Modern Acoustics Ministry of EducationInstitute of Acoustics and School of PhysicsNanjing University

An underwater acoustic metasurface with sub-wavelength thickness is designed for acoustic wavefront *** this paper, a pentamode lattice and a frequency-independent generalized acoustic Snell's law are introduced to overcome the limitations of narrow bandwidth and low transmittance. The bulk modulus and effective density of each unit cell can be tuned simultaneously, which are modulated to guarantee the achievement of refractive index profile and high transmission. Here, we actualize anomalous refraction, generation of non-diffracting Bessel beam, sub-wavelength flat focusing,and surface wave conversion by constructing inhomogeneous acoustic metasurface. This design approach has potential applications in medical ultrasound imaging and underwater acoustic communications.

关键词： metasurface frequency-independent pentamode high transmission

Preparation of Uniform Ni-B Amorphous Alloy Catalyst on CNTs and its Performance for Acetylene Selective Hydrogenation

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Chinese Chemical Letters 2006年第1期17卷 109-112页

作者： Chang Yuan HU feng yi li Rong Bin ZHANG li HUA Department of Chemistry Nanchang University Nanchang 330047

Uniform Ni-B amorphous alloys about 14 nm have been prepared on CNTs-A support,named Ni-B/CNTs-A. In comparison with the Ni-B/CNTs amorphous catalyst, Ni-B/CNTs-A showed higher nickel loading, determined by ICP and be... 详细信息

关键词： CNTs aniline Ni-B amorphous alloy catalyst acetylene selective hydrogenation.

Characterization of machined surface quality and near-surface microstructure of a high speed thrust angular contact ball bearing

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Journal of Materials Science & Technology 2021年第27期86卷 219-226页

作者： Di Wu Xiao-Chen Zhang yi-feng li Jianqiu Wang En-Hou Han Institute of Metal Research Chinese Academy of Sciences62 Wencui RoadShenyang110016China School of Materials Science and Engineering University of Science and Technology of China72 Wenhua RoadShenyang110016China Institute of Materials Shanghai University99 Shangda RoadShanghai200072China

Bearings are one of the most important components in modern *** contact fatigue(RCF)initiating from surface and subsurface is the major failure *** this paper,a typical high speed thrust angular contact ball bearing was selected,and the machined surface quality and near-surface microstructure of the race-way and rolling ball were systematically characterized by using of a probe surface profiler,white light interferometer,optical microscopy(OM),scanning electron microscopy(SEM),electron backscatter diffraction(EBSD)and transmission electron microscopy(TEM)combined with focused ion beam(FIB).Two kinds of precursor,probably resulting in pitting or spalling during the following rolling contact,were *** is the defects on the surface of either the race-way or the rolling ball,such as heavy machining marks,scratches and *** other is nano-crystalline layer due to machining,in the outermost layer around the surface of *** results may well lay foundation for our further research on RCF with the real part of such typical rolling bearings.

关键词： Rolling bearing GCr15 Race-way Rolling ball Machined surface quality Surface nano-crystalline layer

Aluminum matrix composites reinforced by molybdenum-coated carbon nanotubes

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International Journal of Minerals,Metallurgy and Materials 2011年第6期18卷 695-702页

作者： Jun-hui Nie Cheng-chang Jia Na Shi Ya-feng Zhang yi li XianJia School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

To extend the application of carbon nanotubes （CNTs） and explore novel aluminum matrix composites,CNTs were coated by molybdenum layers using metal organic chemical vapor deposition,and then Mo-coated CNT （Mo-CNT）/Al composites were prepared by the combination processes of powder mixing and spark plasma *** influences of powder mixing and Mo-CNT content on the mechanical properties and electrical conductivity of the composites were *** results show that magnetic stirring is better than mechanical milling for mixing the Mo-CNTs and Al *** electrical conductivity of the composites decreases with increasing Mo-CNT *** the Mo-CNT content is 0.5wt%,the tensile strength and hardness of Mo-CNT/Al reach their maximum *** tensile strength of 0.5wt% Mo-CNT/Al increases by 29.9%,while the electrical conductivity only decreases by 7.1%,relative to sintered pure *** phase analysis of Mo-CNT/Al composites reveals that there is no formation of Al carbide in the composites.

关键词： carbon nanotubes aluminum matrix composites molybdenum layer mechanical properties electrical conductivity

Pt Complexes with High Molecular Weight Polyvinylmethyldimethylsiloxane ligands Supported on Diatomite for liquid-phase Hydrosilylation of 3, 3, 3-Trifluoropropene with Methyldichlorosilane

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Chinese Chemical Letters 2006年第6期17卷 803-806页

作者： Hong liu liA0 Huai Jun ZHU feng yi li College of Chemical and Energy South China University of Technology Guangzhou 510640 Chemistry Department of Nanchang University Nanchang 330047

Pt complexes with high molecular weight polyvinylmethyldimethylsiloxane （HMPVMS） ligands supported on diatomite as a catalyst for the hydrosilylation of 3, 3, 3-trifluoropropene and methyldichlorosilane. Results show that this catalyst displays good thermal stability, high activity and excellent recyclability, and it can be readily fabricated by a simple process.

关键词： Pt hydmsilylation high molecular weight polyvinylmethyldimethylsiloxane.

Cascading decomposition of Boolean control networks:a graph-theoretical method

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Frontiers of Information Technology & Electronic Engineering 2020年第2期21卷 304-315页

作者： yi-feng li Jian-dong ZHU Institute of Mathematics School of Mathematical SciencesNanjing Normal UniversityNanjing 210023China

Two types of cascading decomposition problems of Boolean control networks are investigated using a graph-theoretical method.A new graphic concept called nested perfect equal vertex partition(NPEVP)is *** on NPEVP,the necessary and sufficient graphic conditions for solvability of the cascading decomposition problems are *** the proposed graphic conditions,the logical coordinate transformations are constructively obtained to realize the corresponding cascading decomposition ***,two illustrative examples are provided to validate the results.

关键词： Boolean control networks Semi-tensor product Cascading decomposition Graphic condition

Honokiol Prevents Intestinal Barrier Dysfunction in Mice with Severe Acute Pancreatitis and Inhibits JAK/STAT1 Pathway and Acetylation of HMGB1

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Chinese Journal of Integrative Medicine 2024年第6期30卷 534-542页

作者： li Jie CHEN Ya-feng GAO Lei li yi-jie feng Dian-xu Department of General Surgery Putuo HospitalShanghai University of Traditional Chinese MedicineShanghai200062China

Objective To investigate the effect of honokiol(HON)and the role of high-mobility group protein B1(HMGB1)on the pathogenesis of severe acute pancreatitis(SAP).Methods Thirty mice were numbered according to weight,and randomly divided into 5 groups using a random number table,including control,SAP,SAP and normal saline(SAP+NS),SAP and ethyl pyruvate(SAP+EP),or SAP+HON groups,6 mice in each *** of pancreas,intestine,and blood were collected 12 h after SAP model induction for examination of pathologic changes,immune function alterations by enzyme linked immunosorbent assay(EliSA),and Western *** vitro experiments,macrophages were divided into 5 groups,the control,lipopolysaccharide(LPS),LPS+DMSO(DMSO),LPS+anti-HMGB1 monoclonal antibody(mAb),and LPS+HON *** tight connection level was determined by transmission electron microscopy and fluorescein *** location and acetylation of HMGB1 were measured by Western ***,pyridone 6 and silencing signal transducer and activator of the transcription 1(siSTAT1)combined with honokiol were added to determine whether the Janus kinase(JAK)/STAT1 participated in the regulation of honokiol on *** protein expression levels of HMGB1,JAK,and STAT1 were detected using Western *** Mice with SAP had inflammatory injury in the pancreas,bleeding of intestinal tissues,and cells with disrupted *** in the SAP+HON group had significantly fewer pathological *** with SAP also had significant increases in the serum levels of amylase,lipase,HMGB1,tumor necrosis factor-α,interleukin-6,diamine oxidase,endotoxin-1,and *** in the SAP+HON group did not show these abnormalities(Plity,decreased the levels of junctional adhesion molecule C,and elevated intercellular permeability(P<0.01).HON treatment blocked these *** of

关键词： severe acute pancreatitis intestinal barrier dysfunction honokiol high-mobility group protein B1 Januskinase signal transducerand activatorof transcription1