期刊文献+
共找到76,166篇文章
< 1 2 250 >
每页显示 20 50 100
Impact of BRICS Trade Facilitation on China's Exports Using Cross-Border E-Commerce
1
作者 Longling LI Kaimei CHEN Zijian LONG 《Asian Agricultural Research》 2024年第5期1-7,共7页
With the rapid growth of the global digital economy, cross-border e-commerce, as an emerging form of trade, has gradually become a powerful engine to promote the development of global trade. BRICS is an important forc... With the rapid growth of the global digital economy, cross-border e-commerce, as an emerging form of trade, has gradually become a powerful engine to promote the development of global trade. BRICS is an important force in the global economy, and the progress of the BRICS countries' trade facilitation level has an important impact on the global trade environment. This paper conducts an in-depth study of the dynamic changes in BRICS trade facilitation from 2013 to 2022, and uses an extended gravity model to analyze the specific impact of this change on China's exports using cross-border e-commerce. The results show that although the BRICS countries have made some progress in trade facilitation, the overall level still needs to be improved, and there are obvious differences among member countries. However, the improvement of trade facilitation among BRICS countries has undoubtedly brought significant positive effects to China's exports using cross-border e-commerce. 展开更多
关键词 Trade facilitation BRICS cross-border e-commerce Export trade
下载PDF
Anion competition for Li^(+)solvated coordination environments in poly(1,3 dioxolane)electrolyte to enable high-voltage lithium metal solid-state batteries
2
作者 Qiujun Wang Yanqiang Ma +6 位作者 Xiaomeng Jia Di Zhang Zhaojin Li Huilan Sun Qujiang Sun Bo Wang Li-Zhen Fan 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第9期633-641,共9页
Gel-based polymer electrolytes are limited by the polarity of the residual solvent,which restricts the coupling-breaking behaviour during Li^(+)conduction,resulting in the Li^(+)transport kinetics being greatly affect... Gel-based polymer electrolytes are limited by the polarity of the residual solvent,which restricts the coupling-breaking behaviour during Li^(+)conduction,resulting in the Li^(+)transport kinetics being greatly affected.Here,we designed anion competitive gel polymer electrolyte(ACPE)by introducing lithium difluoro(oxalato)borate(LiDFOB)anion into the 1,3-dioxolane(DOL)in situ polymerisation system.ACPE enhances the ionic dipole interaction between Li^(+)and the solvent molecules and synergizes with Li^(+)across the solvation site of the polymer ethylene oxide(EO)unit,combination that greatly improves the Li^(+)transport efficiency.As a result,ACPE exhibits 1.12 mS cm^(−1)ionic conductivity and 0.75 Li^(+)transfer number at room temperature.Additionally,this intra-polymer solvation sheath allows preferential desolvation of DFOB−,which contributes to the formation of kinetically stable anion-derived interphase and effectively mitigates side reactions.Our results demonstrate that the assembled Li||NCM622 solid-state battery exhibits lifespan of over 300 cycles with average Coulombic efficiency of 98.8%and capacity retention of 80.3%.This study introduces a novel approach for ion migration and interface design,paving the way for high-safety and high-energy-density batteries. 展开更多
关键词 Li-metal batteries Poly(1 3-dioxolane) In situ polymerization Solid-state polymer electrolytes Anion competition
下载PDF
Tree allometry responses to competition and complementarity in mixed-species plantations of Betula alnoides
3
作者 Boyao Chen Kaili Liu +5 位作者 Chunsheng Wang Junjie Guo Junkun Lu Lin Chen Zhigang Zhao Jie Zeng 《Forest Ecosystems》 SCIE CSCD 2024年第4期469-479,共11页
Tree allometry plays a crucial role in tree survival,stability,and timber quantity and quality of mixed-species plantations.However,the responses of tree allometry to resource utilisation within the framework of inter... Tree allometry plays a crucial role in tree survival,stability,and timber quantity and quality of mixed-species plantations.However,the responses of tree allometry to resource utilisation within the framework of interspecific competition and complementarity remain poorly understood.Taking into consideration strong-and weakspace competition(SC and WC),as well as N_(2)-fixing and non-N_(2)-fixing tree species(FN and nFN),a mixedspecies planting trial was conducted for Betula alnoides,a pioneer tree species,which was separately mixed with Acacia melanoxylon(SC+FN),Erythrophleum fordii(WC+FN),Eucalyptus cloeziana(SC+nFN)and Pinus kesiya var.langbianensis(WC+nFN)in southern China.Six years after planting,tree growth,total nitrogen(N)and carbon(C)contents,and the natural abundances of^(15)N and^(13)C in the leaves were measured for each species,and the mycorrhizal colonisation rates of B.alnoides were investigated under each treatment.Allometric variations and their relationships with space competition and nutrient-related factors were analyzed.The results showed a consistent effect of space competition on the height-diameter relationship of B.alnoides in mixtures with FN or nFN.The tree height growth of B.alnoides was significantly promoted under high space competition,and growth in diameter at breast height(DBH),tree height and crown size were all expedited in mixtures with FN.The symbiotic relationship between ectomycorrhizal fungi and B.alnoides was significantly influenced by both space competition and N_(2) fixation by the accompanying tree species,whereas such significant effects were absent for arbuscular mycorrhizal fungi.Furthermore,high space competition significantly decreased the water use efficiency(WUE)of B.alnoides,and its N use efficiency(NUE)was much lower in the FN mixtures.Structural equation modeling further demonstrated that the stem allometry of B.alnoides was affected by its NUE and WUE via changes in its height growth,and crown allometry was influenced by the mycorrhizal symbiotic relationship.Our findings provide new insights into the mechanisms driving tree allometric responses to above-and belowground resource competition and complementarity in mixed-species plantations,which are instructive for the establishment of mixed-species plantations. 展开更多
关键词 Allometric relationship Resources competition and complementarity Mixed-species forest Tree-fungal symbiotic relationship N_2-fixing tree species Resource utilisation strategies
下载PDF
Dilemmas and Optimization of Third-Party Assessment System in Chinese Fair Competition Review
4
作者 Cui Xu Mingyu Hu 《Open Journal of Applied Sciences》 2024年第8期2039-2049,共11页
The current predominant self-review mechanism by policy-making bodies suffers from deficiencies such as insufficient motivations, limited review capabilities, and weak external supervision. Third-party assessment, cha... The current predominant self-review mechanism by policy-making bodies suffers from deficiencies such as insufficient motivations, limited review capabilities, and weak external supervision. Third-party assessment, characterized by independence and specialization, is designed to mitigate these shortcomings. However, the implementation of third-party assessment faces challenges too. This paper intends to improve the third-party assessment system and to realize the legislative purpose of the system. Based on social research, discussions and exchanges with relevant parties, and the existing research results, this paper analyzes the challenges and possible optimization measures for the third-party assessment. The challenges include repulsion from policy-making bodies, insufficient independence of assessment bodies, disparity of assessment quality, and limited application of assessment outcomes. Possible optimization measures include promoting fair competition culture, increasing the acceptance of third-party assessment from policy-making bodies, enhancing the quality of third-party assessment, clarifying the relationship between policy-making bodies and assessment bodies, ensuring the independence of third-party assessments, and promoting the application of assessment results. 展开更多
关键词 Fair competition Review Self-Review Third-Party Assessment DILEMMA Optimization
下载PDF
Micro,Small,and Medium Enterprises’Cross-Border Business Strategies
5
作者 Xuan Chen Yijun Xia Tian Hou 《Proceedings of Business and Economic Studies》 2024年第2期191-197,共7页
This paper explores the operational strategies of cross-border micro, small, and medium enterprises (MSMEs). Against the backdrop of globalization and digitalization, cross-border trade has become one of the important... This paper explores the operational strategies of cross-border micro, small, and medium enterprises (MSMEs). Against the backdrop of globalization and digitalization, cross-border trade has become one of the important pathways for many MSMEs to achieve growth and competitive advantage. Firstly, the paper outlines the concept and characteristics of cross-border MSMEs, as well as the analysis of their operational environment in the context of globalization, including political, economic, social, technological, environmental, and legal factors. Secondly, the paper proposes operational strategies for cross-border MSMEs, including international market selection and positioning, cross-border marketing strategies, supply chain management, cross-border financial management, and cross-border risk management. Finally, the paper summarizes the importance of effectively implementing these strategies for cross-border MSMEs to seize international market opportunities, reduce operational risks, and enhance competitiveness and profitability. 展开更多
关键词 cross-border MSMEs Operational strategies GLOBALIZATION DIGITALIZATION International market cross-border trade marketing finance and risk management Supply chain management
下载PDF
Brain-derived neurotrophic factor signaling in the neuromuscular junction during developmental axonal competition and synapse elimination
6
作者 Josep Tomàs Víctor Cilleros-Mañé +7 位作者 Laia Just-Borràs Marta Balanyà-Segura Aleksandra Polishchuk Laura Nadal Marta Tomàs Carolina Silvera-Simón Manel M.Santafé Maria A.Lanuza 《Neural Regeneration Research》 SCIE CAS 2025年第2期394-401,共8页
During the development of the nervous system,there is an overproduction of neurons and synapses.Hebbian competition between neighboring nerve endings and synapses performing different activity levels leads to their el... During the development of the nervous system,there is an overproduction of neurons and synapses.Hebbian competition between neighboring nerve endings and synapses performing different activity levels leads to their elimination or strengthening.We have extensively studied the involvement of the brain-derived neurotrophic factor-Tropomyosin-related kinase B receptor neurotrophic retrograde pathway,at the neuromuscular junction,in the axonal development and synapse elimination process versus the synapse consolidation.The purpose of this review is to describe the neurotrophic influence on developmental synapse elimination,in relation to other molecular pathways that we and others have found to regulate this process.In particular,we summarize our published results based on transmitter release analysis and axonal counts to show the different involvement of the presynaptic acetylcholine muscarinic autoreceptors,coupled to downstream serine-threonine protein kinases A and C(PKA and PKC)and voltage-gated calcium channels,at different nerve endings in developmental competition.The dynamic changes that occur simultaneously in several nerve terminals and synapses converge across a postsynaptic site,influence each other,and require careful studies to individualize the mechanisms of specific endings.We describe an activity-dependent balance(related to the extent of transmitter release)between the presynaptic muscarinic subtypes and the neurotrophin-mediated TrkB/p75NTR pathways that can influence the timing and fate of the competitive interactions between the different axon terminals.The downstream displacement of the PKA/PKC activity ratio to lower values,both in competing nerve terminals and at postsynaptic sites,plays a relevant role in controlling the elimination of supernumerary synapses.Finally,calcium entry through L-and P/Q-subtypes of voltage-gated calcium channels(both channels are present,together with the N-type channel in developing nerve terminals)contributes to reduce transmitter release and promote withdrawal of the most unfavorable nerve terminals during elimination(the weakest in acetylcholine release and those that have already become silent).The main findings contribute to a better understanding of punishment-rewarding interactions between nerve endings during development.Identifying the molecular targets and signaling pathways that allow synapse consolidation or withdrawal of synapses in different situations is important for potential therapies in neurodegenerative diseases. 展开更多
关键词 acetylcholine release adenosine receptors axonal competition brain-derived neurotrophic factor calcium channels motor end-plate muscarinic acetylcholine receptors postnatal synapse elimination serine kinases tropomyosin-related kinase receptorB
下载PDF
Discussion on the Application of Technical and Tactical Skills in Mixed Martial Arts Competitions
7
作者 Yu Huang 《Journal of Contemporary Educational Research》 2024年第2期8-13,共6页
This article mainly analyzes the application of technical and tactical skills in mixed martial arts competitions,including mixed martial arts and its competition characteristics,the main application significance of te... This article mainly analyzes the application of technical and tactical skills in mixed martial arts competitions,including mixed martial arts and its competition characteristics,the main application significance of technical and tactical skills in mixed martial arts competitions,and its primary application strategies.It is hoped that this analysis can provide some guidelines for the appropriate application of mixed martial arts athletes’technical and tactical skills to improve their winning rate in mixed martial arts competitions. 展开更多
关键词 Mixed martial arts competition Technical and tactical skills Fighting awareness Fighting movements competition rhythm
下载PDF
Research on the Role of Guiding Students to Participate in Skills Competitions on the Development of Young Teachers in Vocational Colleges
8
作者 Jinru Ma Meiqin Liang 《Journal of Contemporary Educational Research》 2024年第5期212-217,共6页
This paper explores the role of guiding students to participate in skills competitions on the development of young teachers in vocational colleges.We investigate the impact of skills competitions on the consolidation ... This paper explores the role of guiding students to participate in skills competitions on the development of young teachers in vocational colleges.We investigate the impact of skills competitions on the consolidation of professional knowledge,development of innovation capabilities,improvement of hands-on abilities,and enhancement of communication skills with students.The results of this research demonstrate that skills competitions have a positive influence on the professional growth of young teachers.The consolidation of professional knowledge,development of innovation capabilities,improvement of hands-on abilities,and enhancement of communication skills collectively contribute to the effectiveness of young teachers in vocational colleges.It is recommended that vocational colleges prioritize and support the participation of young teachers in skills competitions to foster their professional development. 展开更多
关键词 Skills competitions Young teachers Vocational colleges Professional development Communication skills
下载PDF
Teaching Design and Implementation of the Electrical and Electronic Technology Course Based on Teaching Ability Competition
9
作者 Xiayida Maxue’er 《Journal of Electronic Research and Application》 2024年第3期66-71,共6页
The teaching ability competition is a vital method for stimulating teachers’enthusiasm and enhancing their teaching skills.This approach has gained increasing attention from colleges and universities in recent years.... The teaching ability competition is a vital method for stimulating teachers’enthusiasm and enhancing their teaching skills.This approach has gained increasing attention from colleges and universities in recent years.The competition focuses on evaluating teachers’capabilities in designing and implementing lessons,encouraging the exchange of new educational ideas and high-quality teaching methods.Reforming the teaching of Electrical and Electronic Technology courses based on insights from teaching competitions can significantly improve teaching quality.This paper explores the teaching design and implementation of the Electrical and Electronic Technology course,drawing on the principles of teaching ability competitions.First,it analyzes the existing problems in teaching this course.Then,it highlights the significant benefits that teaching competitions bring to the course.Based on these insights,the paper proposes practical strategies aimed at enhancing students’interest and practical skills,thereby promoting innovative developments in teaching Electrical and Electronic Technology. 展开更多
关键词 Teaching ability competition Electrical and Electronic Technology Course instructional design Colleges and universities
下载PDF
Discussion on the Integration of“Post,Course,Competition,Certificate”:Taking the Internet of Things Application Technology Courses in Higher Vocational Colleges as an Example
10
作者 Dongmei He 《Journal of Contemporary Educational Research》 2024年第9期25-31,共7页
This article explores the development of the Internet of Things(IoT)application technology course in higher vocational colleges under the background of“post,course,competition,certificate.”It first emphasizes the im... This article explores the development of the Internet of Things(IoT)application technology course in higher vocational colleges under the background of“post,course,competition,certificate.”It first emphasizes the importance of IoT talent training and course construction in higher vocational colleges and deeply analyzes the core concept of“post,course,competition,certificate”integration.In view of the problems faced in the course construction of IoT application technology in higher vocational colleges and the practical experience of Tianjin Vocational College of Mechanics and Electricity,the implementation strategy of the course construction of IoT application technology in higher vocational colleges is elaborated in detail based on the integrated concept of“post,course,competition,certificate.” 展开更多
关键词 Post course competition certificate Course construction Integration of industry and education
下载PDF
The Model of“Post,Course,Competition,Certificate”Integrated Education for Electronic Information Engineering Technology Major in Higher Vocational Colleges
11
作者 Qinqin Jing Yun Liu Xinyu Zheng 《Journal of Contemporary Educational Research》 2024年第5期223-229,共7页
The core education function of higher vocational colleges is to train technical talents with high quality,so as to meet the needs of talents in the development stage of our society.Under the guidance of talent trainin... The core education function of higher vocational colleges is to train technical talents with high quality,so as to meet the needs of talents in the development stage of our society.Under the guidance of talent training,higher vocational colleges need to pay attention to establishing an all-round and three-dimensional education model,and promote innovation of higher vocational education on the basis of this.It is also a way to promote the innovation of higher vocational education to vigorously promote the construction of“post,course,competition,certificate”mode in the construction of education mode.Through the construction of“post,course,competition,certificate”mode,the education mode of higher vocational colleges is gradually improved,so as to strengthen the effectiveness of talent training in higher vocational colleges.Therefore,in this paper,the author puts forward some suggestions to promote the construction of the integrated education mode of the electronic information engineering technology major in higher vocational colleges,so as to help improve the talent training level of higher vocational colleges. 展开更多
关键词 Higher vocational education Electronic information engineering technology major “Post course competition certificate” Integrated education model
下载PDF
Developing nonlinear additive tree crown width models based on decomposed competition index and tree variables 被引量:1
12
作者 Siyu Qiu Peiwen Gao +4 位作者 Lei Pan Lai Zhou Ruiting Liang Yujun Sun Yifu Wang 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第5期1407-1422,共16页
Crown development is closely related to the biomass and growth rate of the tree and its width(CW)is an important covariable in growth and yield models and in forest management.To date,various CW models have been propo... Crown development is closely related to the biomass and growth rate of the tree and its width(CW)is an important covariable in growth and yield models and in forest management.To date,various CW models have been proposed.However,limited studies have explicitly focused on additive and inherent correlation of crown components and total CW as well as the influence of competition on crown radius from the corresponding direction.In this study,two model systems were used,i.e.,aggregation method system(AMS)and disaggregation method system(DMS),to develop crown width additive model systems.For calculating spatially explicit competition index(CI),four neighbor tree selection methods were evaluated.CI was decomposed into four cardinal directions and added into the model systems.Results show that the power model form was more proper for our data to fit CW growth.For each crown radius and total CW,height to the diameter at breast height(HDR)and basal area of trees larger than the subject tree(BAL)significantly contributed to the increase of prediction accuracy.The 3-m fixed radius was optimal among the four neighborhoods selection ways.After adding decomposed competition Hegyi index into model systems AMS and DMS,the prediction accuracy improved.Of the model systems evaluated,AMS based on decomposed CI provided the best performance as well as the inherent correlation and additivity properties.Our study highlighted the importance of decomposed CI in tree CW modelling for additive model systems.This study focused on methodology and could be applied to other species or stands. 展开更多
关键词 competition decomposition ADDITIVITY Crown width Spatially explicit competitor selection
下载PDF
Competitive oxidation behavior of Ni-based superalloy GH4738 at extreme temperature 被引量:3
13
作者 Hui Xu Shufeng Yang +4 位作者 Enhui Wang Yunsong Liu Chunyu Guo Xinmei Hou Yanling Zhang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CSCD 2024年第1期138-145,共8页
A high thrust-to-weight ratio poses challenges to the high-temperature performance of Ni-based superalloys. The oxidation behavior of GH4738 at extreme temperatures has been investigated by isothermal and non-isotherm... A high thrust-to-weight ratio poses challenges to the high-temperature performance of Ni-based superalloys. The oxidation behavior of GH4738 at extreme temperatures has been investigated by isothermal and non-isothermal experiments. As a result of the competitive diffusion of alloying elements, the oxide scale included an outermost porous oxide layer (OOL), an inner relatively dense oxide layer (IOL), and an internal oxide zone (IOZ), depending on the temperature and time. A high temperature led to the formation of large voids at the IOL/IOZ interface. At 1200℃, the continuity of the Cr-rich oxide layer in the IOL was destroyed, and thus, spallation occurred. Extension of oxidation time contributed to the size of Al-rich oxide particles with the increase in the IOZ. Based on this finding,the oxidation kinetics of GH4738 was discussed, and the corresponding oxidation behavior at 900-1100℃ was predicted. 展开更多
关键词 Ni-based superalloy GH4738 extreme temperature competitive oxidation oxidation mechanism oxidation kinetics
下载PDF
Cross-border Urban Networks Based on Manufacturing Global Value Chain:A Study of Listed Companies in Western China
14
作者 MAN Shan YANG Yongchun +1 位作者 ZENG Tonggang WANG Meimei 《Chinese Geographical Science》 SCIE CSCD 2023年第6期1033-1052,共20页
Cross-border investment is essential for western China’s globalization.Global value chain(GVC)forms cross-border investment networks between industries in western China and overseas cities.Focusing on GVC,this study ... Cross-border investment is essential for western China’s globalization.Global value chain(GVC)forms cross-border investment networks between industries in western China and overseas cities.Focusing on GVC,this study uses the social network analysis method,entropy method,multi-index comprehensive evaluation method,and quadratic assignment procedure analysis method to examine the characteristics and influencing factors of the urban networks of research and development(R&D),production,and sales formed as a result of the overseas investments of listed manufacturing companies in western China.Results showed that the three types of investment networks involved multiple industry types and multiple central cities with differentiated diversity and multicentrality.The R&D urban network’s leading sub-industries were the mechanical equipment and instruments,medicine and biological products,and metal and nonmetal industries.The destination cities were mostly those home to educational and scientific research centers.The production urban network’s leading sub-industries were the mechanical equipment,instrument,and food and beverage industries.The destination cities were mostly regional central cities in developing countries.The sales urban network’s leading sub-industries were the mechanical equipment and instrument,metal and nonmetal,and petrochemical and plastics industries.The destination cities were numerous and scattered.In addition,the R&D urban network easily formed specialized clusters,core nodes easily controlled the production urban network,and individual nodes did not easily control the sales urban network.Technological and economic system advantages greatly impacted the three network types.Considering the different influencing factors,this study suggests optimizing the institutional investment environment to narrow the institutional gap,adjusting and optimizing the investment layout to expand overseas markets,and increasing R&D funds to stimulate technological progress and overseas investments in western China. 展开更多
关键词 manufacturing industry Global value chain(GVC) overseas investment cross-border networks western China
下载PDF
ENTIRE SOLUTIONS OF LOTKA-VOLTERRA COMPETITION SYSTEMS WITH NONLOCAL DISPERSAL
15
作者 郝玉霞 李万同 +1 位作者 王佳兵 许文兵 《Acta Mathematica Scientia》 SCIE CSCD 2023年第6期2347-2376,共30页
This paper is mainly concerned with entire solutions of the following two-species Lotka-Volterra competition system with nonlocal(convolution)dispersals:{u_(t)=k*u-u+u(1-u-av),x∈R,t∈R,vt=d(k*v-v)+rv(1-v-bu),c∈R,t∈... This paper is mainly concerned with entire solutions of the following two-species Lotka-Volterra competition system with nonlocal(convolution)dispersals:{u_(t)=k*u-u+u(1-u-av),x∈R,t∈R,vt=d(k*v-v)+rv(1-v-bu),c∈R,t∈R.(0.1)Here a≠1,b≠1,d,and r are positive constants.By studying the eigenvalue problem of(0.1)linearized at(ϕc(ξ),0),we construct a pair of super-and sub-solutions for(0.1),and then establish the existence of entire solutions originating from(ϕc(ξ),0)as t→−∞,whereϕc denotes the traveling wave solution of the nonlocal Fisher-KPP equation ut=k*u−u+u(1−u).Moreover,we give a detailed description on the long-time behavior of such entire solutions as t→∞.Compared to the known works on the Lotka-Volterra competition system with classical diffusions,this paper overcomes many difficulties due to the appearance of nonlocal dispersal operators. 展开更多
关键词 entire solutions Lotka-Volterra competition systems nonlocal dispersal traveling waves
下载PDF
GPU parallel computation of dendrite growth competition in forced convection using the multi-phase-field-lattice Boltzmann model
16
作者 高梓豪 朱昶胜 王苍龙 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第7期530-547,共18页
A graphics-processing-unit(GPU)-parallel-based computational scheme is developed to realize the competitive growth process of converging bi-crystal in two-dimensional states in the presence of forced convection condit... A graphics-processing-unit(GPU)-parallel-based computational scheme is developed to realize the competitive growth process of converging bi-crystal in two-dimensional states in the presence of forced convection conditions by coupling a multi-phase field model and a lattice Boltzmann model.The elimination mechanism in the evolution process is analyzed for the three conformational schemes constituting converging bi-crystals under pure diffusion and forced convection conditions,respectively,expanding the research of the competitive growth of columnar dendrites under melt convection conditions.The results show that the elimination mechanism for the competitive growth of converging bi-crystals of all three configurations under pure diffusion conditions follows the conventional Walton-Chalmers model.When there is forced convection with lateral flow in the liquid phase,the anomalous elimination phenomenon of unfavorable dendrites eliminating favorable dendrites occurs in the grain boundaries.In particular,the anomalous elimination phenomenon is relatively strong in conformation 1 and conformation 2 when the orientation angle of unfavorable dendrites is small,and relatively weak in conformation 3.Moreover,the presence of convection increases the tip growth rate of both favorable and unfavorable dendrites in the grain boundary.In addition,the parallelization of the multi-phase-field-lattice Boltzmann model is achieved by designing the parallel computation of the model on the GPU platform concerning the computerunified-device-architecture parallel technique,and the results show that the parallel computation of this model based on the GPU has absolute advantages,and the parallel acceleration is more obvious as the computation area increases. 展开更多
关键词 multi-phase field model GPU grain competition growth lattice Boltzmann model
下载PDF
Digital Development Rights in Developing Countries:Where the Governance Rules for Cross-Border Data Flows
17
作者 李艳华 JIANG Yu(译) 《The Journal of Human Rights》 2023年第5期1040-1066,共27页
The digital development rights in developing countries are based on establishing a new international economic order and ensuring equal participation in the digital globalization process to achieve people's well-ro... The digital development rights in developing countries are based on establishing a new international economic order and ensuring equal participation in the digital globalization process to achieve people's well-rounded development in the digital society.The relationship between cross-border data flows and the realization of digital development rights in developing countries is quite complex.Currently,developing countries seek to safeguard their existing digital interests through unilateral regulation to protect data sovereignty and multilateral regulation for cross-border data cooperation.However,developing countries still have to face internal conflicts between national digital development rights and individual and corporate digital development rights during the process of realizing digital development rights.They also encounter external contradictions such as developed countries interfering with developing countries'data sovereignty,developed countries squeezing the policy space of developing countries through dominant rules,and developing countries having conflicts between domestic and international rules.This article argues that balancing openness and security on digital trade platforms is the optimal solution for developing countries to realize their digital development rights.The establishment of WTO digital trade rules should inherently reflect the fundamental demands of developing countries in cross-border data flows.At the same time,given China's dual role as a digital powerhouse and a developing country,it should actively promote the realization of digital development rights in developing countries. 展开更多
关键词 developing countries digital development rights cross-border data flows governance rules
下载PDF
Competitive effect, but not competitive response, varies along a climatic gradient depending on tree species identity
18
作者 Teresa Valor Lluís Coll +9 位作者 David I.Forrester Hans Pretzsch Miren del Río Kamil Bielak Bogdan Brzeziecki Franz Binder Torben Hilmers Zuzana Sitková Roberto Tognetti Aitor Ameztegui 《Forest Ecosystems》 SCIE CSCD 2024年第2期142-151,共10页
Background: Understanding the role of species identity in interactions among individuals is crucial for assessing the productivity and stability of mixed forests over time. However, there is limited knowledge concerni... Background: Understanding the role of species identity in interactions among individuals is crucial for assessing the productivity and stability of mixed forests over time. However, there is limited knowledge concerning the variation in competitive effect and response of different species along climatic gradients. In this study, we investigated the importance of climate, tree size, and competition on the growth of three tree species: spruce(Picea abies), fir(Abies alba), and beech(Fagus sylvatica), and examined their competitive response and effect along a climatic gradient.Methods: We selected 39 plots distributed across the European mountains with records of the position and growth of 5,759 individuals. For each target species, models relating tree growth to tree size, climate and competition were proposed. Competition was modelled using a neighbourhood competition index that considered the effects of inter-and intraspecific competition on target trees. Competitive responses and effects were related to climate.Likelihood methods and information theory were used to select the best model.Results: Our findings revealed that competition had a greater impact on target species growth than tree size or climate. Climate did influence the competitive effects of neighbouring species, but it did not affect the target species? response to competition. The strength of competitive effects varied along the gradient, contingent on the identity of the interacting species. When the target species exhibited an intermediate competitive effect relative to neighbouring species, both higher inter-than intraspecific competitive effects and competition reduction occurred along the gradient. Notably, species competitive effects were most pronounced when the target species' growth was at its peak and weakest when growing conditions were far from their maximum.Conclusions: Climate modulates the effects of competition from neighbouring trees on the target tree and not the susceptibility of the target tree to competition. The modelling approach should be useful in future research to expand our knowledge of how competition modulates forest communities across environmental gradients. 展开更多
关键词 competition coefficient competition reduction Interspecific competition Intraspecific competition Mixing effects Mixed species forest Neighbourhood models Plant-plant interactions
下载PDF
Analysis of the Development Environment and Trend of Cross-Border E-commerce in China
19
作者 Yanxia Li Can Xu Ping Zhu 《Proceedings of Business and Economic Studies》 2023年第6期30-38,共9页
With the conclusion of the novel coronavirus pandemic and the increasingly complex market environment,China’s cross-border e-commerce has entered a new phase of development.The external landscape is evolving rapidly,... With the conclusion of the novel coronavirus pandemic and the increasingly complex market environment,China’s cross-border e-commerce has entered a new phase of development.The external landscape is evolving rapidly,and there is a gradual improvement in laws and regulations governing cross-border e-commerce,coupled with increased government support.Despite the impact of the COVID-19 pandemic on the market economy,overall development has been steadily improving.The Internet population is expanding,the online retail market is experiencing rapid growth,the consumption structure is undergoing transformation and upgrading,and the e-commerce market is demonstrating significant potential.The advancement of technologies such as big data,artificial intelligence,blockchain,and supply chain has provided more efficient operational support for the cross-border e-commerce industry.Against the backdrop of the emergence of new forms of cross-border e-commerce in China post-pandemic,this paper utilizes the PEST model to analyze the macro environment of cross-border e-commerce in China and project its future development trends. 展开更多
关键词 cross-border e-commerce Environmental analysis Development trend
下载PDF
Live-streaming selling strategies for competitive firms
20
作者 Quan Du Zhixin Chen +1 位作者 Jie Wu Xiang Ji 《中国科学技术大学学报》 CAS CSCD 北大核心 2024年第5期22-35,I0006,I0007,共16页
The booming live-streaming commerce has significantly changed the traditional e-commerce model,thus attracting much attention from both industry and academia.In recent years,an increasing number of scholars have appli... The booming live-streaming commerce has significantly changed the traditional e-commerce model,thus attracting much attention from both industry and academia.In recent years,an increasing number of scholars have applied analytical models to explore live-streaming strategies for firms in different scenarios.However,the previous literature mainly considers monopolists,while in the real world,competition is not rare.To fill this gap between the literature and practical observations,this paper applies a game theoretical model to study live-streaming adoption and pricing strategy for firms under competitive environments.The results show that,for competitive firms,the equilibrium strategy depends on the relation between the commission rate and the intensity of the market expansion effect.Additionally,compared to the case in which no firm adopts live-streaming,competitive firms do not always benefit from the adoption of live-streaming selling.The paper also shows that competition plays a negative role in inducing a firm to adopt live-streaming. 展开更多
关键词 live-streaming commerce live-streaming strategy game competition
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部