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Competitive oxidation behavior of Ni-based superalloy GH4738 at extreme temperature 被引量:3
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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
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Competitive effect, but not competitive response, varies along a climatic gradient depending on tree species identity
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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
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Live-streaming selling strategies for competitive firms
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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
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Optimal Control for Age Distribution and Weighted Size Competitive Species in a Polluted Environment
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作者 WANG Zhanping 《应用数学》 北大核心 2024年第4期1014-1026,共13页
In the paper,we study an optimal control for a system representing a competitive species model with fertility and mortality depending on a weighted size in a polluted environment.A fixed point theorem is applied to ob... In the paper,we study an optimal control for a system representing a competitive species model with fertility and mortality depending on a weighted size in a polluted environment.A fixed point theorem is applied to obtain the existence and uniqueness exhibited by a non-negative solution of above mentioned model.A maximum principle helps to carefully verify the existence of the optimal control policy,and tangent-normal cone techniques help to obtain the optimal condition specific to control issue. 展开更多
关键词 Optimal control competitive species POLLUTION Maximum principle
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CRB:A new rumor blocking algorithm in online social networks based on competitive spreading model and influence maximization
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作者 董晨 徐桂琼 孟蕾 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期588-604,共17页
The virtuality and openness of online social platforms make networks a hotbed for the rapid propagation of various rumors.In order to block the outbreak of rumor,one of the most effective containment measures is sprea... The virtuality and openness of online social platforms make networks a hotbed for the rapid propagation of various rumors.In order to block the outbreak of rumor,one of the most effective containment measures is spreading positive information to counterbalance the diffusion of rumor.The spreading mechanism of rumors and effective suppression strategies are significant and challenging research issues.Firstly,in order to simulate the dissemination of multiple types of information,we propose a competitive linear threshold model with state transition(CLTST)to describe the spreading process of rumor and anti-rumor in the same network.Subsequently,we put forward a community-based rumor blocking(CRB)algorithm based on influence maximization theory in social networks.Its crucial step is to identify a set of influential seeds that propagate anti-rumor information to other nodes,which includes community detection,selection of candidate anti-rumor seeds and generation of anti-rumor seed set.Under the CLTST model,the CRB algorithm has been compared with six state-of-the-art algorithms on nine online social networks to verify the performance.Experimental results show that the proposed model can better reflect the process of rumor propagation,and review the propagation mechanism of rumor and anti-rumor in online social networks.Moreover,the proposed CRB algorithm has better performance in weakening the rumor dissemination ability,which can select anti-rumor seeds in networks more accurately and achieve better performance in influence spread,sensitivity analysis,seeds distribution and running time. 展开更多
关键词 online social networks rumor blocking competitive linear threshold model influence maximization
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Construction of CDKN2A-related competitive endogenous RNA network and identification of GAS5 as a prognostic indicator for hepatocellular carcinoma
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作者 Yong Pan Yi-Ru Zhang +4 位作者 Ling-Yun Wang Li-Na Wu Ying-Qiu Ma Zhou Fang Shi-Bo Li 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第4期1514-1531,共18页
BACKGROUND Competitive endogenous RNA(ceRNA)is an innovative way of gene expression modulation,which plays a crucial part in neoplasia.However,the intricacy and behavioral characteristics of the ceRNA network in hepat... BACKGROUND Competitive endogenous RNA(ceRNA)is an innovative way of gene expression modulation,which plays a crucial part in neoplasia.However,the intricacy and behavioral characteristics of the ceRNA network in hepatocellular carcinoma(HCC)remain dismal.AIM To establish a cyclin dependent kinase inhibitor 2A(CDKN2A)-related ceRNA network and recognize potential prognostic indicators for HCC.METHODS The mutation landscape of CDKN2A in HCC was first explored using the cBioPortal database.Differential expression analysis was implemented between CDKN2Ahigh and CDKN2Alow expression HCC samples.The targeted microRNAs were predicted by lncBasev3.0,and the targeted mRNAs were predicted by miRDB,and Targetscan database.The univariate and multivariate analysis were utilized to identify independent prognostic indicators.RESULTS CDKN2A was frequently mutated and deleted in HCC.The single-cell RNA-sequencing analysis revealed that CDKN2A participated in cell cycle pathways.The CDKN2A-related ceRNA network-growth arrest specific 5(GAS5)/miR-25-3p/SRY-box transcription factor 11(SOX11)was successfully established.GAS5 was recognized as an independent prognostic biomarker,whose overexpression was correlated with a poor prognosis in HCC patients.The association between GAS5 expression and methylation,immune infilt-ration was explored.Besides,traditional Chinese medicine effective components targeting GAS5 were obtained.CONCLUSION This CDKN2A-related ceRNA network provides innovative insights into the molecular mechanism of HCC formation and progression.Moreover,GAS5 might be a significant prognostic biomarker and therapeutic target in HCC. 展开更多
关键词 Hepatocellular carcinoma competitive endogenous RNA Molecular mechanism Prognosis Biomarker
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A Cooperated Imperialist Competitive Algorithm for Unrelated Parallel Batch Machine Scheduling Problem
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作者 Deming Lei Heen Li 《Computers, Materials & Continua》 SCIE EI 2024年第5期1855-1874,共20页
This study focuses on the scheduling problem of unrelated parallel batch processing machines(BPM)with release times,a scenario derived from the moulding process in a foundry.In this process,a batch is initially formed... This study focuses on the scheduling problem of unrelated parallel batch processing machines(BPM)with release times,a scenario derived from the moulding process in a foundry.In this process,a batch is initially formed,placed in a sandbox,and then the sandbox is positioned on a BPM formoulding.The complexity of the scheduling problem increases due to the consideration of BPM capacity and sandbox volume.To minimize the makespan,a new cooperated imperialist competitive algorithm(CICA)is introduced.In CICA,the number of empires is not a parameter,and four empires aremaintained throughout the search process.Two types of assimilations are achieved:The strongest and weakest empires cooperate in their assimilation,while the remaining two empires,having a close normalization total cost,combine in their assimilation.A new form of imperialist competition is proposed to prevent insufficient competition,and the unique features of the problem are effectively utilized.Computational experiments are conducted across several instances,and a significant amount of experimental results show that the newstrategies of CICAare effective,indicating promising advantages for the considered BPMscheduling problems. 展开更多
关键词 Release time ASSIMILATION imperialist competitive algorithm batch processing machines scheduling
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Treatment of Helicobacter pylori with potassium competitive acid blockers:A systematic review and meta-analysis
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作者 Joseph Edwin Kanu Jonathan Soldera 《World Journal of Gastroenterology》 SCIE CAS 2024年第9期1213-1223,共11页
BACKGROUND Helicobacter pylori(H.pylori)infects over half the global population,causing gastrointestinal diseases like dyspepsia,gastritis,duodenitis,peptic ulcers,GMALT lymphoma,and gastric adenocarcinoma.Eradicating... BACKGROUND Helicobacter pylori(H.pylori)infects over half the global population,causing gastrointestinal diseases like dyspepsia,gastritis,duodenitis,peptic ulcers,GMALT lymphoma,and gastric adenocarcinoma.Eradicating H.pylori is crucial for treating and preventing these conditions.While conventional proton pump inhibitor(PPI)-based triple therapy is effective,there’s growing interest in longer acid suppression therapies.Potassium competitive acid blocker(P-CAB)triple and dual therapy are new regimens for H.pylori eradication.Initially used in Asian populations,vonoprazan(VPZ)has been recently Food and Drug Administration-approved for H.pylori eradication.AIM To assess the efficacy of regimens containing P-CABs in eradicating H.pylori infection.METHODS This study,following PRISMA 2020 guidelines,conducted a systematic review and meta-analysis by searching MEDLINE and Scopus libraries for randomized clinical trials(RCTs)or observational studies with the following command:[("Helicobacter pylori"OR"H pylori")AND("Treatment"OR"Therapy"OR"Eradication")AND("Vonaprazan"OR"Potassium-Competitive Acid Blocker"OR"P-CAB"OR"PCAB"OR"Revaprazan"OR"Linaprazan"OR"Soraprazan"OR"Tegoprazan")].Studies comparing the efficacy of P-CABs-based treatment to classical PPIs in eradicating H.pylori were included.Exclusion criteria included case reports,case series,unpublished trials,or conference abstracts.Data variables encompassed age,diagnosis method,sample sizes,study duration,intervention and control,and H.pylori eradication method were gathered by two independent reviewers.Meta-analysis was performed in R software,and forest plots were generated.RESULTS A total of 256 references were initially retrieved through the search command.Ultimately,fifteen studies(7 RCTs,7 retrospective observational studies,and 1 comparative unique study)were included,comparing P-CAB triple therapy to PPI triple therapy.The intention-to-treat analysis involved 8049 patients,with 4471 in the P-CAB intervention group and 3578 in the PPI control group across these studies.The analysis revealed a significant difference in H.pylori eradication between VPZ triple therapy and PPI triple therapy in both RCTs and observational studies[risk ratio(RR)=1.17,95%confidence interval(CI):1.11-1.22,P<0.0001]and(RR=1.13,95%CI:1.09-1.17,P<0.0001],respectively.However,no significant difference was found between tegoprazan(TPZ)triple therapy and PPI triple therapy in both RCTs and observational studies(RR=1.04,95%CI:0.93-1.16,P=0.5)and(RR=1.03,95%CI:0.97-1.10,P=0.3),respectively.CONCLUSION VPZ-based triple therapy outperformed conventional PPI-based triple therapy in eradicating H.pylori,positioning it as a highly effective first-line regimen.Additionally,TPZ-based triple therapy was non-inferior to classical PPI triple therapy. 展开更多
关键词 Helicobacter pylori infection Potassium competitive acid blockers Proton pump inhibitors Vonoprazan AMOXICILLIN
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Extensive numerical simulations on competitive growth between the Edwards–Wilkinson and Kardar–Parisi–Zhang universality classes
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作者 余成志 刘潇 +1 位作者 唐军 夏辉 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期298-307,共10页
Extensive numerical simulations and scaling analysis are performed to investigate competitive growth between the linear and nonlinear stochastic dynamic growth systems, which belong to the Edwards–Wilkinson(EW) and K... Extensive numerical simulations and scaling analysis are performed to investigate competitive growth between the linear and nonlinear stochastic dynamic growth systems, which belong to the Edwards–Wilkinson(EW) and Kardar–Parisi–Zhang(KPZ) universality classes, respectively. The linear growth systems include the EW equation and the model of random deposition with surface relaxation(RDSR), the nonlinear growth systems involve the KPZ equation and typical discrete models including ballistic deposition(BD), etching, and restricted solid on solid(RSOS). The scaling exponents are obtained in both the(1 + 1)-and(2 + 1)-dimensional competitive growth with the nonlinear growth probability p and the linear proportion 1-p. Our results show that, when p changes from 0 to 1, there exist non-trivial crossover effects from EW to KPZ universality classes based on different competitive growth rules. Furthermore, the growth rate and the porosity are also estimated within various linear and nonlinear growths of cooperation and competition. 展开更多
关键词 competitive growth scaling behavior discrete growth model Kardar–Parisi–Zhang universality class
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Enhancement of Competitiveness of Border Trade Entrepreneurs: Case Study of Su-Ngai Kolok Checkpoint, Narathiwat Province
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作者 Sumalee Grodgangunt Roihan Saaree +2 位作者 Chonlakan Satabodee Rungsiri Padungrat Mathurose Tongintharach 《Management Studies》 2024年第4期225-244,共20页
This research aimed to analyze the enhancement of competitiveness among fruit and vegetable export entrepreneurs,with the case study of the Su-ngai Kolok checkpoint in Narathiwat Province.This research focused on thre... This research aimed to analyze the enhancement of competitiveness among fruit and vegetable export entrepreneurs,with the case study of the Su-ngai Kolok checkpoint in Narathiwat Province.This research focused on three objectives:(1)examining how competitiveness is enhanced through government support and the development of border trade zones,(2)studying the supply chain dynamics,including strategic factors and opportunities in agricultural product management,and(3)developing a model for border trade to strengthen exporters’capabilities.The research employed qualitative methods,with data collected from 25 informants through interviews and employed descriptive methods.The research results revealed that:(1)government agencies play a crucial role in improving competitiveness by developing border economic zones and trade policies;additionally,(2)the research highlighted the importance of strategic partnerships,network building,and efficient logistics along the value chain;(3)the proposed Border Trade Model includes elements for instance government policy,partnerships,entrepreneurial potential,and transportation channels,aiming to enhance the overall efficiency and effectiveness of vegetable and fruit exporters in the region. 展开更多
关键词 ENHANCEMENT competitiveNESS border trade entrepreneurs
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Impact of coupling coordination development of port and city environments on urban economic competitiveness:Evidence from the coastal port cities in eastern China
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作者 LI Zhen-qiang YI Ying +2 位作者 LI Jia-li YOU Xiao-yue ZHOU Qiu-yang 《Ecological Economy》 2024年第1期53-71,共19页
Promoting the coupling coordination development of port and its hinterland city environments is an important way to improve urban economic competitiveness.Based on relevant data of 13 coastal port cities in eastern Ch... Promoting the coupling coordination development of port and its hinterland city environments is an important way to improve urban economic competitiveness.Based on relevant data of 13 coastal port cities in eastern China from 2000 to 2018,this study explores the coupling coordination development of port and city environments and its impact on urban economic competitiveness by constructing the coupling coordination degree model and the panel threshold model.The research results show that:(1)In terms of the coupling coordination development of port and city environments,most coastal ports and their hinterland cities are in a state of moderate or serious disorder.Overall,the degree of coupling coordination of port and city environments needs to be further improved;(2)The coupling coordination degree of port and city environments has a significant impact on urban economic competitiveness,and this effect gradually increases with the development of the ports and the urban economy.Among the variables that impact the urban economic competitiveness,fixed assets investment and foreign trade are significant factors that can enhance urban economic competitiveness.(3)At present,there is a“U-shaped”relationship between the coupling coordination degree of port-city environments and the urban economic competitiveness.This relationship lies on the right side of the inflection point of the“U-shaped”curve.Therefore,following the concept of assigning priority to ecological development,expanding fixed assets investment and actively developing foreign trade can further enhance the urban economic competitiveness. 展开更多
关键词 coastal ports city environments coupling coordination degree urban economic competitiveness threshold effect
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Export Competitiveness and Sustainable Development of the Ukrainian Timber Industry
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作者 Anastasiia Shapiro 《Open Journal of Applied Sciences》 2024年第10期2777-2789,共13页
This paper conducts a comprehensive analysis of the export dynamics within the Ukrainian timber industry, emphasizing its pivotal role in the national economy. The study begins by outlining the research objectives, co... This paper conducts a comprehensive analysis of the export dynamics within the Ukrainian timber industry, emphasizing its pivotal role in the national economy. The study begins by outlining the research objectives, context, and innovative methodologies, setting the stage for a deep dive into the theoretical underpinnings of sustainable and competitive trade. It explores Ukraine’s rich forest biodiversity across varied vegetation zones and its geopolitical significance. Detailed evaluations of forest resource management, policy frameworks, and institutional support form the core of the analysis. Challenges such as imbalanced export structures and legal inconsistencies are critically examined. The research employs trade gravity models and competitive indicators like the Revealed Comparative Advantage (RCA) and Market Share (MS) to assess factors influencing exports and to forecast potential growth areas. The findings inform strategic recommendations aimed at enhancing export capacity through market diversification, brand development, and legal stability. The conclusion highlights the need for strategic interventions to harness Ukraine’s timber resources sustainably, balancing economic gains with environmental stewardship. 展开更多
关键词 Ukrainian Timber Industry Export Dynamics Export competitiveness Sustainable Trade Forest Resource Management
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The competitive dynamics of Bangladesh and Turkey in apparel exports
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《China Textile》 2024年第3期54-55,共2页
Turkish-made apparel now costs approximately 40%more than similar products from Bangladesh,a gap that was only 15-20%a few years ago.This is creating opportunities for Bangladeshi exporters to attract consumer's a... Turkish-made apparel now costs approximately 40%more than similar products from Bangladesh,a gap that was only 15-20%a few years ago.This is creating opportunities for Bangladeshi exporters to attract consumer's attention. 展开更多
关键词 competitive BANGLADESH CONSUMER
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Strategies for Boxing Teaching in Competitive Sports Schools
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作者 Yu Huang 《Journal of Contemporary Educational Research》 2024年第7期258-263,共6页
To improve the quality of boxing teaching in competitive sports schools,it is necessary to first analyze the strengths and weaknesses of boxing teaching in competitive sports schools,and then optimize the teaching str... To improve the quality of boxing teaching in competitive sports schools,it is necessary to first analyze the strengths and weaknesses of boxing teaching in competitive sports schools,and then optimize the teaching strategy.The strategies include innovating the boxing curriculum system and content,building learning communities inside and outside the classroom,personalizing the teaching forms and methods,using multimedia to broaden the teaching path,focusing on the integration of boxing teaching leagues,and diversifying the teaching incentives and evaluations. 展开更多
关键词 competitive sports schools BOXING Teaching strategies
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Analysis of Porter’s Five Forces Competitive Model in China’s Property Rights Trading Market
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作者 Weinong Wang 《Proceedings of Business and Economic Studies》 2024年第3期206-211,共6页
In recent years,China’s property rights trading market has been extremely competitive,but there are also new contradictions and challenges.This paper aims to analyze the external and internal competitive market of th... In recent years,China’s property rights trading market has been extremely competitive,but there are also new contradictions and challenges.This paper aims to analyze the external and internal competitive market of the property rights market through Porter’s five forces competition model,then find out the problems and defects in the development,thereby promoting the better development and progress of China’s property rights trading market. 展开更多
关键词 Porter’s five forces competitive model Market optimization Innovative development
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美国家庭校外活动的“鸡娃书评”史与儿童竞争资本的制造——Playing to Win: Raising Children in a Competitive Culture
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作者 李一 《中华家教》 2024年第4期80-88,共9页
自20世纪80年代起,校外活动在美国家庭生活中逐渐占据重要地位,并具备了显著的竞争性意义,这也导致中产及以上阶层父母将大量金钱和精力投入到儿童校外生活中。希拉里·弗瑞德曼的Playing to Win:Raising Children in a Competitive... 自20世纪80年代起,校外活动在美国家庭生活中逐渐占据重要地位,并具备了显著的竞争性意义,这也导致中产及以上阶层父母将大量金钱和精力投入到儿童校外生活中。希拉里·弗瑞德曼的Playing to Win:Raising Children in a Competitive Culture一书深入剖析了美国中产及以上阶层家庭校外活动的历史背景、活动内容以及竞争资本的转化机制等,详细记录了家长们如何通过国际象棋、足球、舞蹈等校外竞技活动,看似在“玩”,实际上却是引导儿童内化竞争意识、积累竞争资本,揭示了美国父母“鸡娃”现象与社会竞争加剧、阶层固化之间的内在联系。这对于理解当前中国中产阶层家庭的教育选择具有重要参考价值。 展开更多
关键词 美国家庭 校外活动 “鸡娃” 竞争资本
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Co-evolution of the brand effect and competitiveness in evolving networks 被引量:1
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作者 郭进利 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第7期230-237,共8页
The principle that 'the brand effect is attractive' underlies the preferential attachment. Here we show that the brand effect is just one dimension of attractiveness. Another dimension is competitiveness. We firstly... The principle that 'the brand effect is attractive' underlies the preferential attachment. Here we show that the brand effect is just one dimension of attractiveness. Another dimension is competitiveness. We firstly introduce a general frame- work that allows us to investigate the competitive aspect of real networks, instead of simply preferring popular nodes. Our model accurately describes the evolution of social and technological networks. The phenomenon that more competitive nodes become richer can help us to understand the evolution of many competitive systems in nature and society. In general, the paper provides an explicit analytical expression of degree distributions of the network. In particular, the model yields a nontrivial time evolution of nodes' properties and the scale-free behavior with exponents depending on the microscopic parameters characterizing the competition rules. Secondly, through theoretical analyses and numerical simulations, we reveal that our model has not only the universality for the homogeneous weighted network, but also the character for the heterogeneous weighted network. Thirdly, we also develop a model based on the profit-driven mechanism. It can better describe the observed phenomenon in enterprise cooperation networks. We show that the standard preferential attachment, the growing random graph, the initial attractiveness model, the fitness model, and weighted networks can all be seen as degenerate cases of our model. 展开更多
关键词 complex network weighted network scale-free network competitive network
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Method for Evaluating Bolt Competitive Failure Life Under Composite Excitation 被引量:1
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作者 Guangwu Yang Long Yang +3 位作者 Han Zhao Haoxu Ding Bing Yang Shoune Xiao 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2023年第4期372-384,共13页
In this study,the competitive failure mechanism of bolt loosening and fatigue is elucidated via competitive failure tests on bolts under composite excitation.Based on the competitive failure mechanism,the mode predict... In this study,the competitive failure mechanism of bolt loosening and fatigue is elucidated via competitive failure tests on bolts under composite excitation.Based on the competitive failure mechanism,the mode prediction model and“load ratio-life prediction curve”(ξ-N curve)of the bolt competitive failure are established.Given the poor correlation of theξ-N curve,an evaluation model of the bolt competitive failure life is proposed based on Miner’s linear damage accumulation theory.Based on the force analysis of the thread surface and simulation of the bolt connection under composite excitation,a theoretical equation of the bolt competitive failure life is established to validate the model for evaluating the bolt competitive failure life.The results reveal that the proposed model can accurately predict the competitive failure life of bolts under composite excitation,and thereby,it can provide guidance to engineering applications. 展开更多
关键词 BOLT competitive failure life Evaluation model Mode prediction model Composite excitation
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Forge ahead and improve the core competitiveness of Animal Models and Experimental Medicine(AMEM)
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作者 Jian-Dong Jiang 《Animal Models and Experimental Medicine》 CAS CSCD 2023年第1期2-2,共1页
After 5 years of accumulation, Animal Models and Experimental Medicine(AMEM) has received 396 manuscripts from 46 countries and regions, including Chinese mainland, Iran, the United States, India, Israel, Nigeria, Bra... After 5 years of accumulation, Animal Models and Experimental Medicine(AMEM) has received 396 manuscripts from 46 countries and regions, including Chinese mainland, Iran, the United States, India, Israel, Nigeria, Brazil, Bangladesh, Sri Lanka, the Netherlands, Denmark, Australia, Japan, and Spain. It has become an important international exchange and display platform for innovative research results in the field of laboratory animal science and basic medicine. 展开更多
关键词 competitiveNESS MAINLAND Israel
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Effect of Bt traits on transgenic rice's growth and weed competitiveness
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作者 WANG Kang-xu ZHANG Ke-rou +1 位作者 CAO Cou-gui JIANG Yang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第8期2346-2358,共13页
Transgene escape could lead to genetically modified rice establishing wild populations in the natural environment and competing for survival space with weeds.However,whether the expression of the Bacillus thuringiensi... Transgene escape could lead to genetically modified rice establishing wild populations in the natural environment and competing for survival space with weeds.However,whether the expression of the Bacillus thuringiensis(Bt)gene in rice will alter the relationship between transgene plants and weeds and induce undesirable environmental consequences are poorly understood.Thus,field experiments were conducted to investigate the weed competitiveness and assess the ecological risk of transgenic Bt rice under herbicide-free and lepidopterous pest-controlled environments.Results showed that weed–rice competition in the direct-sowing(DS)field was earlier and more severe than that in the transplanting(TP)field,which resulted in a significant decrease in biomass and yield in DS.However,conventional Bt and non-Bt rice yield was not significantly different.The weed number,weed coverage ratio,and weed diversity of conventional Bt rice were significantly higher than those of non-Bt rice at the early growth and mature stages,especially in DS plots,suggesting that Bt traits did not increase the weed competitiveness of transgenic rice and had no negative effect on weed diversity.Grain yield and weed number varied between different hybrid rice lines,but those differences were insignificant between Bt and non-Bt rice.The number of insects increased with the increase of weeds in hybrid rice plots,whereas the insect number and diversity did not display a significant difference between Bt and non-Bt rice.Therefore,the ecological risk of transgenic Bt rice is comparable to non-Bt rice. 展开更多
关键词 BIOSAFETY field evaluation genetically modified crops Oryza sativa weed competitiveness
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