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Frontiers of Engineering Management 2024年第1期11卷 128-142页

作者： Xiaowei SHI Qiang WEI Guoqing CHEN School of Economics and Management Tsinghua UniversityBeijing 100084China

Amidst the inefficiencies of traditional job-seeking approaches in the recruitment ecosystem, the importance of automated job recommendation systems has been magnified. However, existing models optimized to maximize user clicks for general product recommendations prove inept in addressing the unique challenges of job recommendation, namely reciprocity and competition. Moreover, sparse data on online recruitment platforms can further negatively impact the performance of existing job recommendation algorithms. To counteract these limitations, we propose a bilateral heterogeneous graph-based competition iteration model. This model comprises three integral components: 1) two bilateral heterogeneous graphs for capturing multi-source information from people and jobs and alleviating data sparsity, 2) fusion strategies for synthesizing attributes and preferences to produce mutually beneficial job matches, and 3) a competition-enhancing strategy for dispersing competition realized through a two-stage optimization algorithm. Augmented by granular attention mechanisms for enhanced interpretability, the model’s efficacy, competition dispersion, and interpretability are validated through rigorous empirical evaluations on a real-world recruitment platform.

关键词： job recommendation competition reciprocity interpretability

Overshoot phenomena:Observation and simulation

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Earth and Planetary Physics 2024年第2期8卷 391-399页

作者： Ting Feng MoRan Liu ShiMin He Xiang Wang Chen Zhou Department of Space Physics School of Electronic InformationWuhan UniversityWuhan 430072China

High-power O-mode radio waves can excite artificial instabilities in the F region,according to experiments conducted at the European Incoherent Scatter Science Association(EISCAT)heating facility.The main instabilities include the parametric decay instability(PDI),oscillating two-stream instability(OTSI),and thermal parametric instability(TPI).The PDI and OTSI not only compete with each other,but also compete with the TPI,leading to a two-stage overshoot phenomenon:a miniovershoot occurs on a millisecond time scale after pump-on,followed by the main overshoot.We gain insight into the miniovershoot via a generalized Zakharov model,whereas the main overshoot can be observed as an enhanced plasma line overshoot phenomenon in incoherent scatter radar spectra.We can also observe that the zero-frequency ion line exists only in the initial heating period after a cold start and that the upshifted and downshifted ion lines behave irregularly in the spectra.The simulation results show that competition between the PDI and OTSI leads to an initial peak,which we named the pre-miniovershoot.The following processes,namely ion density caviton generation,and collapse and cascade in the development of the PDI,contribute to the miniovershoot phenomenon.

关键词： overshoot parametric decay instability oscillating two-stream instability competition

Population Dynamics in an Advective Environment

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Communications on Applied Mathematics and Computation 2024年第1期6卷 399-430页

作者： King-Yeung Lam Ray Lee Yuan Lou Department of Mathematics The Ohio State UniversityColumbusOH43210USA School of Mathematical Sciences CMA-Shanghai and MOE-LSCShanghai Jiao Tong UniversityShanghai200240China

We consider a one-dimensional reaction-diffusion equation describing single-and two-species population dynamics in an advective environment,based on the modeling frameworks proposed by Lutscher et al.in 2006.We analyze the effect of rate of loss of individuals at both the upstream and downstream boundaries.In the single-species case,we prove the existence of the critical domain size and provide explicit formulas in terms of model parameters.We further derive qualitative properties of the critical domain size and show that,in some cases,the critical domain size is either strictly decreasing over all diffusion rates,or monotonically increasing after first decreasing to a minimum.We also consider competition between species differing only in their diffusion rates.For two species having large diffusion rates,we give a sufficient condition to determine whether the faster or slower diffuser wins the competition.We also briefly discuss applications of these results to competition in species whose spatial niche is affected by shifting isotherms caused by climate change.

关键词： Reaction-diffusion-advection Critical domain size competition Climate change

Twenty years of population dynamics in European beech-oak forest at their rear range margin anticipate changes in its structure and composition

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Forest Ecosystems 2024年第3期11卷 358-370页

作者： álvaro Rubio-Cuadrado Iciar Alberdi Isabel Canellas Fernando Montes Jesús Rodríguez-Calcerrada Rosana López Guillermo G.Gordaliza María Valbuena-Carabana Nikos Nanos Ramón Perea Luis Gil Departamento de dinamica y gestion forestal Instituto de Ciencias Forestales(ICIFOR-INIA)CSICCtra.La Coruna km 7.528040MadridSpain Departamento de Sistemas y Recursos Naturales Escuela Tecnica Superior de Ingeniería de MontesForestal y del Medio NaturalUniversidad Politecnica de Madrid.Ciudad Universitaria s/n28040MadridSpain School of Forestry and Natural Environment Aristotle University of ThessalonikiUniversity Campus54124ThessalonikiGreece

There is an increasing interest in restoring degraded forests,which occupy half of the forest areas.Among the forms of restoration,passive restoration,which involves the elimination of degrading factors and the free evolution of natural dynamics by applying minimal or no management,is gaining attention.Natural dynamics is difficult to predict due to the influence of multiple interacting factors such as climatic and edaphic conditions,composition and abundance of species,and the successional character of these species.Here,we study the natural dynamics of a mixed forest located in central Spain,which maintained an open forest structure,due to intensive use,until grazing and cutting were banned in the 1960s.The most frequent woody species in this forest are Fagus sylvatica,Quercus petraea,Quercus pyrenaica,Ilex aquifolium,Sorbus aucuparia,Sorbus aria and Prunus avium,with contrasting shade and drought tolerance.These species are common in temperate European deciduous forest and are found here near their southern distribution limit,except for Q.pyrenaica.In order to analyze forest dynamics and composition,three inventories were carried out in 1994,2005 and 2015.Our results show that,despite the Mediterranean influence,the natural dynamics of this forest has been mainly determined by different levels of shade tolerance.After the abandonment of grazing and cutting,Q.pyrenaica expanded rapidly due to its lower shade tolerance,whereas after canopy closure and forest densification,shade-tolerant species gained ground,particularly F.sylvatica,despite its lower drought and late-frost tolerance.If the current dynamics continue,F.sylvatica will overtake the rest of the species,which will be relegated to sites with shallow soils and steep slopes.Simultaneously,all the multi-centennial beech trees,which are undergoing a rapid mortality and decline process,will disappear.

关键词： Forest succession Secondary forest Woodland Mixed forest competition Recruitment

Quality disclosure strategies for small business enterprises under consumer loss aversion

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Journal of Management Science and Engineering 2024年第1期9卷 62-87页

作者： Danli Yao Simai He Meng Zheng Business School University of Shanghai for Science and TechnologyShanghai200093China School of Information Management and Engineering Shanghai University of Finance and EconomicsShanghai200433China

In this paper,we focus on small business enterprises(SBEs)that usually have low market power but can rely on retailers to transact sales and gain the ability to disclose quality information.Moreover,consumer loss aversion(CLA)is pronounced when buying from SBEs that have yet to develop a strong reputation and uncertain quality.We focus on two competing SBEs with heterogeneous quality levels and discuss their quality disclosure strategiesd whether selling through a retailerd in the context of CLA.We study the interaction between consumers'prior belief in product quality and CLA and how these factors affect equilibrium outcomes.We show that a situation in which low-quality and high-quality SBEs both choose to disclose will not occur under a neutral consumer attitude,i.e.,it happens only when the aversion level is significant.When the aversion level is low,either the low-quality SBE or the high-quality SBE will decide to disclose,and the disclosing party depends on the prior belief.In addition,CLA significantly impacts the monotonicity of both SBEs'and retailers'prices and profits relating to the consumers'prior beliefs.

关键词： Quality disclosure Consumer loss aversion competition Game theory

competition of insect decomposers over large vertebrate carrion:Necrodes beetles(Silphidae)vs.blow flies(Calliphoridae)

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Current Zoology 2022年第6期68卷 645-656页

作者： Szymon MATUSZEWSKI Anna MADRA-BIELEWICZ Laboratory of Criminalistics Adam Mickiewicz UniversityPoznan 61-809Poland Wielkopolska Centre for Advanced Technologies Adam Mickiewicz UniversityPoznan 61-614Poland

Large carrion is inhabited by highly variable and interactive communities of insects.Positive interactions in carrion insect communities have been recently the focus in carrion ecology.In contrast,competition between carrion insects is rather undervalued.Here we provide evidence that blow flies(Calliphoridae)and Necrodes beetles(Silphidae),dominant decomposers of large carcasses in terrestrial habitats,compete over carrion.By reanalyzing the results from 90 pig carcasses,we demonstrated that the contribution of the flies and the beetles to the decay was negatively related.The greater part of the large carrion pool was monopolized by blow flies,whereas Necrodes beetles abundantly colonized carcasses,on which blow flies were less effective as decomposers.In behavioral assays,we found that adult beetles killed 4 times more frequently feeding than postfeeding third instar larvae of the flies,with the large decrease in the killing frequency after the larvae reached the age of early third instar.Therefore,adult Necrodes beetles preferentially killed the larvae that were before or in their peak feeding.The study provides evidence that the interaction between blow flies and Necrodes beetles is a combination of indirect exploitative effects of the flies and direct interference effects of the beetles(the mixed competition).

关键词： carrion competition interspecific interactions

competition,spatial pattern,and regeneration of Haloxylon ammodendron and Haloxylon persicum communities in the Gurbantunggut Desert,Northwest China

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Journal of Arid Land 2022年第10期14卷 1138-1158页

作者： LIU Yaxuan ZENG Yong YANG Yuhui WANG Ning LIANG Yuejia Xinjiang Laboratory of Lake Environment and Resources in Arid Zone Urumqi 830054China College of Geographic Science and Tourism Xinjiang Normal UniversityUrumqi 830054China School of Geography and Tourism Shaanxi Normal UniversityXi'an 710119China

competition,spatial pattern,and regeneration are important factors affecting community composition,structure,and dynamics.In this study,we surveyed 300 quadrats from three dunes(i.e.,fixed dunes,semifixed dunes,and mobile dunes)in the Gurbantunggut Desert,Northwest China,from late May to early June in 2021.The intraspecific and interspecific competition,spatial pattern,and regeneration of Haloxylon ammodendron and Haloxylon persicum were studied using the Hegyi competition index and point pattern analysis methods.The results showed that the optimal competition distance of the objective tree in the H.ammodendron and H.persicum communities was 6 m.The intraspecific and interspecific competition of H.ammodendron was the greatest in fixed dunes,while the competition intensity of H.persicum in semifixed dunes and mobile dunes was greater than that in fixed dunes.The order of competition intensity of the two populations was seedlings>saplings>adults,and the competition intensity gradually decreased with the increase in plant diameter.The spatial distribution pattern of the three life stages of H.ammodendron and H.persicum was random,and there were no correlations between seedlings and saplings,adults and saplings,and seedlings and adults.The density of regenerated seedlings and saplings of H.ammodendron in the three dunes followed the order of fixed dunes>semifixed dunes>mobile dunes,and that of H.persicum in the three dunes followed the order of mobile dunes>semifixed dunes>fixed dunes.Therefore,when artificially planting H.ammodendron and H.persicum for sand control,the planting interval should be 6 m,and seedlings should be planted next to adults to minimize the competition between plants,which can promote the renewal of H.ammodendron and H.persicum and the stabilization of the ecosystem.

关键词： competition spatial pattern regeneration Haloxylon ammodendron Haloxylon persicum Gurbantunggut Desert

Spacecraft collision avoidance challenge:Design and results of a machine learning competition

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Astrodynamics 2022年第2期6卷 121-140页

作者： Thomas Uriot Dario Izzo Luís FSimões Rasit Abay Nils Einecke Sven Rebhan Jose Martinez-Heras Francesca Letizia Jan Siminski Klaus Merz The European Space Agency Noordwijk2201 AZthe Netherlands ML Analytics LisbonPortugal FuturifAI CanberraAustralia Honda Research Institute Europe GmbH Offenbach 63073Germany ESOC Space Debris OfficeDarmstadt 64293Germany

Spacecraft collision avoidance procedures have become an essential part of satellite operations.Complex and constantly updated estimates of the collision risk between orbiting objects inform various operators who can then plan risk mitigation measures.Such measures can be aided by the development of suitable machine learning(ML)models that predict,for example,the evolution of the collision risk over time.In October 2019,in an attempt to study this opportunity,the European Space Agency released a large curated dataset containing information about close approach events in the form of conjunction data messages(CDMs),which was collected from 2015 to 2019.This dataset was used in the Spacecraft Collision Avoidance Challenge,which was an ML competition where participants had to build models to predict the final collision risk between orbiting objects.This paper describes the design and results of the competition and discusses the challenges and lessons learned when applying ML methods to this problem domain.

关键词： space debris collision avoidance competition kelvins

Local mate competition model alone cannot predict the offspring sex ratio in large and dense populations of a haplodiploid arthropod

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Current Zoology 2023年第2期69卷 219-221页

作者： Nuwan Weerawansha Qiao Wang Xiong Zhao He School of Agriculture and Environment Massey UniversityPrivate Bag 11222Palmerston North 4442New Zeal Faculty of Animal Science and Export Agriculture Uva Wellassa University of Sri LankaPassara RoadBadulla 90000Sri Lanka

Sex ratio in animals has profound impacts on the fitness of mothers and their offspring.When the local competition intensity is sex-specific,selection favors the sex that may mitigate such negative impacts(West 2009).This may occur under 1)local mate competition(LMC)-in a discrete population established by one or a few foundresses,they tend to produce female-biased offspring sex ratio to reduce the LMC between related males(Hamilton 1967);2)local resource competition(LRC)-in a dense population where related individuals compete for resources,mothers are selected to produce more off spring of dispersive sex to decrease resource competition(Clark 1978;Wild and Taylor 2004;Iritani et al.2021),and 3)local resource enhancement(LRE)-when one sex helps one another rather than compete with one another,selection favors an excess production of the more helpful sex(Taylor 1981).

关键词： competition cooperation population sizeanddensity sexallocation

The Logic of Digital Finance in the Age of Digital Economy

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Proceedings of Business and Economic Studies 2024年第2期7卷 53-59页

作者： Zhuoyuan Chen University of New South Wales Sydney 2052Australia

This paper explores the development logic,trends,and challenges of digital finance in the era of the digital economy.As a crucial component of the digital economy,digital finance has completely transformed the traditional financial services model through factors such as technological innovation,data intelligence,and personalized user experiences,paving the way for new business models and market opportunities.However,the rapid development of digital finance also faces challenges such as competition,security,and regulation.This paper emphasizes the importance of finding a balance between innovation and security in the development of digital finance and discusses the potential of digital finance in promoting financial inclusion and sustainable development.Through comprehensive analysis,this paper aims to provide valuable insights for academic researchers and industry practitioners,promoting the healthy development of digital finance.

关键词： Digital economy Digital finance Technological innovation Data intelligence User experience competition Security Regulation Financial inclusion Sustainable development