Technological Breakthrough and Domestic Substitution of Key Products Based on Asymmetric Competition:Taking the Integrated Circuit Industry as an Example

Integrated circuit is a typical key product in the digital economy era.Given external containment,breakthroughs in core technologies of integrated circuit are confronted with barriers of first movers in underlying technological ecology and with their threats of decoupling from the supply chain.Currently,China has various bottlenecks in the proprietary industrial ecosystem,and domestic substitution lacks effective overall planning.Therefore,it is essential to apply the underlying logic of asymmetric competition and to leverage a relatively complete industrial system,abundant application scenarios,solid talent base,and the institutional advantages of the new system for mobilizing resources nationwide to break through in integrated circuit manufacturing technologyand in domestic substitution.As such,it is necessary to further strengthen the top-level design,leverage the advantages of the new system for mobilizing resources nationwide to enhance the institutiona1lguarantee for domestic substitution of bottlenecks,and enhance basic research to consolidate the technological foundation for domestic substitution.Moreover,we should implement talent strategy to enhanceethe driving force of human resource for domestic substitution development.We should also further opening-up and cooperation policy to create an open domestic substitution ecology.In addition,we should increase counter-cyclical investment to nurture leaderssin asymmetric competition,and seize the demand window to drive domestic substitution with"epoch-making products."

Asymmetric competition for light varies across functional groups

Aims Asymmetric competition for light may depress the growth rates(GRs)to different extents for different-sized tree individuals.Various responses of different functional groups to light availability result that tree individuals of different functional groups may experience different competition intensities,e.g.canopy and deciduous species grow faster and demand more light than understory and evergreen species.In this study,we estimated the effects of asymmetric competition for light using individual GRs and explored the effects of asymmetric competition on growth among different functional groups(e.g.canopy vs.understory species and deciduous vs.evergreen species).Methods We measured growth in circumference to determine the radial increments of a total of 2233 stems with diameter at breast height≥5.0 cm in a permanent plot(140×80 m^(2))located in a typical evergreen and deciduous broadleaved mixed forest on Mt Shennongjia,China.All of the measurements were carried out at~6-month intervals every April and October from 2012 to 2014,and biomass of each individual was calculated based on its diameter and species-specific allometry.We then calculated GRs of annual biomass growth(growth between October and the next October).Considering the hypothesis that asymmetric competition for light among trees of different sizes may result in a steeper allometric growth curve with increasing tree size,we further divided the sampled trees into different subsets according to their height,at intervals of 1 m,and then fitted the scaling relationship between the logarithm of the biomass GR(logGR)and the logarithm of diameter(logD)for each height class using standardized major axis regression.Finally,we used simple linear regression to test whether the scaling exponent was related to tree height.The above analyses were conducted for the annual growth of all tree species,canopy species,understory vs.treelets species and deciduous vs.evergreen species.Important findings We observed a concave curve for the relationship between logGR and logD with an increase in the scaling exponent between logGR and logD with increasing tree height.This pattern held for the annual growth of canopy species and deciduous species but not for the annual growth of understory species,treelets or evergreen species.These results suggest that asymmetric competition for light is more important in regulating the GRs of the fast-growing species,such as canopy species and deciduous species,than those of shade-tolerant species,such as understory species,treelets and evergreen species.

Problems with models assessing influences of tree size and inter-tree competitive processes on individual tree growth:a cautionary tale

In forest growing at any one site, the growth rate of an individual tree is determined principally by its size, which reflects its metabolic capacity, and by competition from neighboring trees. Competitive effects of a tree may be proportional to its size;such competition is termed ‘sym-metric’ and generally involves competition below ground for nutrients and water from the soil. Competition may also be ‘asymmetric’, where its effects are disproportionate to the size of the tree;this generally involves competition above ground for sunlight, when larger trees shade smaller, but the reverse cannot occur. This work examines three model systems often seen as exemplars relating individual tree growth rates to tree size and both competitive processes. Data of tree stem basal area growth rates in plots of even- aged, monoculture forest of blackbutt (Eucalyptus pilularis Smith) growing in sub-tropical eastern Australia were used to test these systems. It was found that none could distin-guish between size and competitive effects at any time in any one stand and, thus, allow quantification of the contribution of each to explaining tree growth rates. They were prevented from doing so both by collinearity between the terms used to describe each of the effects and technical problems involved in the use of nonlinear least-squares regression to fit the models to any one data set. It is concluded that quite new approaches need to be devised if the effects on tree growth of tree size and competitive processes are to be quantified and modelled successfully.

Tax Burden,Institutional Environment and Foreign Direct Investment Flow:From the Perspective of Asymmetric International Tax Competition

The global economic uncertainty is mounting.Governments need to respond with supporting measures for long-term external environment changes as they lower tax burden to attract working capital.Based on the asymmetric tax competition theory,this paper constructs a theoretical model of tax burden,institutional transaction costs and FDI flow.It is found that one country’s strength of institutional environment makes its equilibrium tax rate higher than that of another within certain limits of market size.Based on the data of 199 countries and regions from 2005 to 2018,this paper conducts an empirical analysis,proving that favorable institutional environment narrows the negative impact of tax burden on FDI fl ow.Moreover,it is showed that in small-market,low-income countries and regions,tax burden level has a larger negative impact on foreign direct investment(FDI)when institutional environment produces no positive impact;in large-market,high-income countries,the negative impact of tax burden is relatively weak but the institutional environment shows largely positive impact.This paper contributes some policy recommendations on how to make use of and improve institutional environment to meet challenges and impacts of the international economic climate.

Context-dependent responses of food-hoarding to competitors in Apodemus peninsulae:implications for coexistence among asymmetrical species

Superior species may have distinct advantages over subordinates within asymmetrical interactions among sympatric animals.However,exactly how the subordinate species coexists with superior species is unknown.In the forests west of Beijing City,intense asymmetrical interactions of food competition exist among granivorous rodents(e.g.Apodemus peninsulae,Niviventer confucianus,Sciurotamias davidianus and Tscherskia triton)that have broadly overlapping habitats and diets but have varied body size(range 15-300 g),hoarding habits(scatter vs larder)and/or daily rhythm(diurnal vs nocturnal).The smallest rodent,A.peninsulae,which typically faces high competitive pressure from larger rodents,is an ideal model to explore how subordinate species coexist with superior species.Under semi-natural enclosure conditions,we tested responses of seed-hoarding behavior in A.peninsulae to intraspecific and interspecific competitors in the situations of pre-competition(without competitor),competition(with competitor)and post-competition(competitor removed).The results showed that for A.peninsulae,the intensity of larder-hoarding increased and the intensity of scatter-hoarding declined in the presence of intraspecifics and S.davidianus,whereas A.peninsulae ceased foraging and hoarding in the presence of N.confucianus and T.triton.A.peninsulae reduced intensity of hoarding outside the nest and moved more seeds into the nest for larder-hoarding under competition from intraspecific individuals and S.davidianus.In most cases,the experimental animals could recover to their original state of pre-competition when competitors were removed.These results suggest that subordinate species contextually regulate their food-hoarding strategies according to different competitors,promoting species coexistence among sympatric animals that have asymmetrical food competition.

How reproductive allocation and flowering probability of individuals in plant populations are affected by position in stand size hierarchy,plant size and CO_(2) regime

Aims We investigate the effect of position within a size-structured population on the reproductive allocation(RA)and flowering probability of individual plants of Sinapis arvensis.We also assess the effects of plant size and changing level of CO_(2) on both responses.Methods Sinapis arvensis L.,(field mustard),an annual agricultural weed,was grown in monoculture at six densities under ambient and elevated CO_(2) in a study with 84 stands.Individual aboveground biomass and reproductive biomass were measured.Varying density produced a wide range of mean plant sizes across stands and size hierarchies within stands.Many(;40%)individuals had zero reproductive biomass.Employing a novel modelling approach,we analysed the joint effects of position in stand size hierarchy,plant size and CO_(2) on RA and flowering probability of individuals.Important Findings We found a strong effect of position within the size hierarchy of individuals in a population:for an individual of a given size,greater size relative to neighbours substantially increased RA and flowering probability at a single harvest time.There was no other effect of plant size on RA.We found a positive effect of elevated CO_(2) on RA regardless of position within the size hierarchy.These observed patterns could impact doubly on the reproductive biomass(R)of small individuals.First,because RA is not affected by size,smaller plants will have smaller R than larger plants;and second,for smaller plants lower down in a population size hierarchy,their RA and hence R will be further reduced.These results suggest that size relative to neighbours may be independent of and more important than direct abiotic effects in determining RA.Further studies are required to evaluate how these observed patterns generalize to other populations in non-experimental conditions.