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Upgrading Pathways of Intelligent Manufacturing in China:Transitioning across Technological Paradigms

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Engineering 2019年第4期5卷 691-701页

作者： Yuan Zhou jiyuan Zang Zhongzhen Miao Tim Minshall School of Public Policy and Management Tsinghua UniversityBeijing 100084China Center for Strategic Studies Chinese Academy of EngineeringBeijing 100088China Institute for Manufacturing University of CambridgeCambridge CB3 0FSUK

Intelligent technologies are leading to the next wave of industrial revolution in *** developed economies,firms are embracing these advanced technologies following a sequential upgrading strategy-from digital manufacturing to smart manufacturing(digital-networked),and then to newgeneration intelligent manufacturing ***,Chinese firms face a different *** the one hand,they have diverse technological bases that vary from low-end electrified machinery to leading-edge digital-network technologies;thus,they may not follow an identical upgrading *** the other hand,Chinese firms aim to rapidly catch up and transition from technology followers to probable frontrunners;thus,the turbulences in the transitioning phase may trigger a precious opportunity for leapfrogging,if Chinese manufacturers can swiftly acquire domain expertise through the adoption of intelligent manufacturing *** study addresses the following question by conducting multiple case studies:Can Chinese firms upgrade intelligent manufacturing through different pathways than the sequential one followed in developed economies?The data sources include semistructured interviews and archival *** study finds that Chinese manufacturing firms have a variety of pathways to transition across the three technological paradigms of intelligent manufacturing in nonconsecutive *** finding implies that Chinese firms may strategize their own upgrading pathways toward intelligent manufacturing according to their capabilities and industrial specifics;furthermore,this finding can be extended to other catching-up *** paper provides a strategic roadmap as an explanatory guide to manufacturing firms,policymakers,and investors.

关键词： Intelligent manufacturing Upgrading pathways China’s manufacturing Digitalization Networkization New-generation intelligent manufacturing

Asymptotic Mandelbrot Law for Some Evolving Networks

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Tsinghua Science and Technology 2012年第3期17卷 310-312页

作者： jiyuan Tan Li Li Yi Zhang Tsinghua National Laboratory for Information Science and Technology Department of AutomationTsinghua UniversityBeijing 100084China

Complex networks are now the focus of many branches of research. Particularly, the scale-free property of some networks is of great interest, due to their importance and pervasiveness. Recent studies have shown that in some complex networks, e.g., transportation networks and social collaboration networks, the degree distribution follows the so-called ＂shifted power law＂（or Mandelbrot law） P（k）oc （k ＋cyy. This study analyzes some evolving networks that grow with linear preferential attachments. Recent results for the quotient Gamma function are used to prove the asymptotic Mandelbrot law for the degree distribution in certain conditions. The best fit values for the scaling exponent, y, and the shifting coefficient, c, can be directly calculated using Bernoulli polynomial functions. The study proves that the degree distribution of some complex networks follows an asymptotic Mandelbrot law with linear preferential attachment depicted by p（k） .

关键词： complex networks scale-free asymptotic Mandelbrot law

A micro-investigation on water bridge effects for unsaturated granular materials with constant water content by discrete element method

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Particuology 2023年第12期83卷 50-62页

作者： Mengchen Li jiyuan Luan xuguang Gao Ji-Peng Wang Abdelali Dadda School of Civil Engineering Shandong University17922 Jingshi RoadJinan250061China

The most common state of surface soil is *** in water content will substantially impact its strength,leading to geological and engineering *** paper used LIGGGHTS software to simulate the water bridge effect of unsaturated granular materials with constant water content and verify the rationality of the simplification of the stress-force-fabric(SFF)*** results showed that the capillary force was not isotropic,which was different from the previous study,thus it cannot be overlooked in the simplification of the SFF ***,the influence of water content on the macroscopic mechanical behavior of unsaturated granular materials was interpreted through the evolutions of coordination number,interparticle force,fabric and force anisotropy,and other microscopic *** to the literature,we found that different water bridge models would not change the characteristics of the solid skeleton.

关键词： Unsaturated granular material Water bridge effect Water content Discrete element method Stress-force-fabric(SFF)relationship

Aligned Ni nanowires towards highly stretchable electrode

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Science China(Technological Sciences) 2020年第10期63卷 2131-2136页

作者： LI JiDong NIU jiyuan LI xueMei ZHOU JianXin HU ZhiLi GUO WanLin State Key Laboratory of Mechanics and Control of Mechanical Structures The Key Laboratory of Intelligent Nano Materials and Devices of DoEInstitute of Nano Science of Nanjing University of Aeronautics and AstronauticsNanjing 210016China

Easy fabrication of super-stretchable electrodes can pave the way for smart and wearable *** drop casting unidirectional nickel nanowires with polyurethane matrix,we fabricated a super-stretchable film with high electric *** as-fabricated film can withstand a 300%tensile strain in the direction perpendicular to nanowires,owing to the transformation of percolating nanowire network from 2D to *** contrast to the decreased film conductivities under large tension in most stretchable electrodes,which usually associate with fractures and irreversible deformations,our film conductivity can increase with the applied *** probably benefits from the enhanced electrical contacts between twisted nanowires under *** developed super-stretchable film with unprecedented behavior in this work sheds light on the facile fabrication of super-stretchable electrodes with durable performance.

关键词： nickel nanowire stretchable electrode polyurethane matrix three-dimensional network alignment

Effects of temperature and particle size on the thermophysical properties of six plant-origin protein supplements

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International Journal of Agricultural and Biological Engineering 2023年第6期16卷 263-272页

作者： Dandan Kong jiyuan Chen Hongying Wang Yong He College of Biosystems Engineering and Food Science Zhejiang UniversityHangzhou 310058China Key Laboratory of Spectroscopy Sensing Ministry of Agriculture and Rural AffairsHangzhou 310058China College of Engineering China Agricultural UniversityBeijing 100083China

Reasonable design of the parameters of thermal processing such as conditioning and cooling according to formula changes of pelleted feeds has always been a serious challenge for Chinese feed mills and feed equipment manufacturers. Studying the thermophysical properties of different protein feeds under different temperatures and particle sizes will facilitate the equipment design, parameter optimization, and simulation for the thermal processing of pelleted feeds. In this study, the specific heat (Cp), thermal conductivity (kb), and thermal diffusivity (α) of six plant protein supplements with three particle sizes were determined over a temperature range of 25℃-100℃. The differences in Cp, kb, and α among different feedstuffs and particle sizes were analyzed and the influences of temperature and particle size on these properties were evaluated. Results showed that the Cp, kb, and α of all the feedstuffs increased with increasing temperature and varied from 1.622 to 2.417 kJ/(kg∙℃), 0.080 to 0.362 W/(m∙℃), 6.379×10^(-8) to 21.984×10^(-8) m^(2)/s, respectively. To rise to the same temperature, the distiller’s dried grain with solubles (DDGS) needed to absorb 3% more heat than that required for soybean meal (SBM), while the rest four feedstuffs just needed to absorb 93%-98% heat for SBM. Particle size had no significant effect on Cp for all the feedstuffs (p>0.05). However, descending trends in kb and α were observed with increasing particle size for a certain feedstuff at the same bulk density. In addition, regression equations with only statistically significant terms were developed to describe Cp, kb, and α as a function of temperature and particle size for six feedstuffs. The results can provide basic theory and data for the optimization of thermal processing parameters required for the plant-protein ingredient change in compound feed formulations.

关键词： plant protein supplement specific heat thermal conductivity thermal diffusivity particle size

A Study on the Transfer of China’s Manufacturing under the Adjustment of Global Industrial Layout-An Analysis Based on the Multi-Regional Input-Output Model of China and the United States

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China Finance and Economic Review 2020年第3期9卷 26-49页

作者： Guoliang Hu jiyuan Wang Zhong An Joint Investment Group Co. Ltd. Institute of Territorial Development&Regional Economy Chinese Academy of Macroeconomic Research

Based on the multi-regional input-output model and WIOD data in 2014,this paper quantitatively estimates the impact of manufacturing transfer on China’s GDP and industrial structure from three technological categories of manufacturing,two stages and three *** paper finds that:(1)China’s exports to the United States are mainly high-tech products,and high-tech manufacturing is greatly constrained by the United States,which requires close attention.(2)Manufacturing transfer has an impact through three channels,*** effect,correlation effect and spillover *** effect is the main channel of infl uence in the short term,but in the long term,spillover effect is the main factor causing inter-sector differences.(3)In the short run,the transfer of low-tech manufacturing has the greatest impact on China’s GDP,while in the long run,the transfer of medium-and high-tech manufacturing will exert much stronger impact than that of low-tech manufacturing,and low-tech manufacturing is less helpful for the upgrading of China’s industrial *** order to mitigate the impact of industrial transfer,this paper suggests that differentiated policies be adopted for different technological categories of manufacturing,with special focus on strengthening the dominance and irreplaceability of medium-and high-tech manufacturing in the industrial chain in China.

关键词： industrial transfer manufacturing transfer GDP industrial structure

Influence of Steam and Sulfide on High Temperature Selective Catalytic Reduction

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Fluid Dynamics & Materials Processing 2020年第3期16卷 615-621页

作者： jiyuan Zhang Linbo Wang Chengqiang Zhang Shuzhan Bai R&D Center Weichai Power Co.Ltd.Weifang261041China School of Energy and Power Engineering Shandong UniversityJinan250061China

The influences of steam and sulfide on the efficiency of NOx reduction using ammonia(NH_(3))over the nanometer-class V-W/Ti catalyst in conditions of high temperature is experimentally investigated using a steady-flow *** results showed that selective catalytic reduction(SCR)is inhibited by H_(2)O at low temperature,but higher NO conversion efficiency is achieved at high temperature since the reaction of NH_(3) oxidized by O_(2) to NOx is inhibited by H_(2)*** activity of SCR is promoted by SO_(2) in the temperature range of 200~500℃,the NO conversion efficiency was improved to 98%from 94%by adding SO_(2).SCR would be improved at 350~500℃ when H_(2)O and SO_(2) exist at the same ***,the positive influence to the NOx conversion was proved in the presence of H_(2)O and SO_(2) as a result of the European Stationary Cycle test.

关键词： High temperature selective catalytic reduction efficiency

Spatio-temporal characteristics of soil protection efforts of the Grain for Green Project in northern Shaanxi Province

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Journal of Geographical Sciences 2020年第3期30卷 401-422页

作者： LIU Wenchao LIU jiyuan KUANG Wenhui Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China School of Geographic and Environmental Sciences Tianjin Normal UniversityTianjin 300387China

This paper looks at the Green for Grain Project in northern Shaanxi *** on remote sensing monitoring data,this study analyzes the locations of arable land in northern Shaanxi in the years 2000,2010 and 2013 as well as spatio-temporal changes over that period,and then incorporates data on the distribution of terraced fields to improve the input parameters of a RUSLE model and simulate and generate raster data on soil erosion for northern Shaanxi at different stages with a accuracy ***,combined with the dataset of farmland change,compared and analyzed the characteristics of soil erosion change in the converted farmland to forest(grassland)and the unconverted farmland in northern Shaanxi,so as to determine the project’s impact on soil erosion over time across the *** results show that between 2000 and 2010,the soil erosion modulus of repurposed farmland in northern Shaanxi decreased 22.7 t/ha,equivalent to 47.08%of the soil erosion modulus of repurposed farmland in *** the same period,the soil erosion modulus of non-repurposed farmland fell 10.99 t/ha,equivalent to 28.6%of the soil erosion modulus of non-repurposed farmland in *** soil erosion modulus for all types of land in northern Shaanxi decreased by an average of 14.51 t/ha between 2000 and 2010,equivalent to 41.87%of the soil erosion modulus for the entire region in *** suggests that the Green for Grain Project effectively reduced the soil erosion modulus,thus helping to protect the *** particular,arable land that was turned into forest and grassland reduced erosion most noticeably and contributed most to soil ***,in the period 2010 to 2013,which was a period of consolidation of the Green for Grain Project,the soil erosion modulus and change in volume of soil erosion in northern Shaanxi were significantly lower than in the previous decade.

关键词： northern Shaanxi converting farmland into forest and grassland remote sensing RUSLE soil erosion soil conservation

Thermo-hydraulic experimental validation of an integrated modular small reactor operating in full power natural circulation

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Science China(Technological Sciences) 2014年第1期57卷 1-8页

作者： YANG XingTuan REN Cheng LIU ZhiYong TU jiyuan JIANG ShengYao Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of Education Institute of Nuclear and New Energy Technology Tsinghua University

Small reactors have become a new hotspot of international nuclear energy *** nuclear heating reactor(NHR)technology developed by Tsinghua University is an important multipurpose small reactor solution with features such as high integration,modular design and full power natural circulation.A new small reactor based on the existing NHR-200 reactor was developed by the Institute of Nuclear and New Energy Technology of Tsinghua University.A full-scale natural circulation test loop with the same operating parameters as the actual reactor was built in order to experimentally validate the natural circulation ability of the reactor primary loop and heat-transfer ability of fuel assemblies and heat *** results are given in detail,including parameter validation of the reactor primary loop,flow rules of the natural circulation and heat-transfer coefficients of heaters and heat exchangers,which can be directly used in the actual reactor as a reference for optimization ***,a characteristic parameter k is proposed to represent the natural circulation ability of a *** using the new data arrangement method in the form of parameter k,comprehensive experimental results of the natural circulation can be represented by a simple integrated *** work in this paper is of importance in broadening application fields and pushing forward commercialization of the NHR type reactors.

关键词： small reactor natural circulation validation experiment