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| 1 | 亚言语的理论与应用显示文摘成晓光,辽 宁 师 范 大 | 成晓光 | 1999 | 外语与外语教学1999，，9： | 39 |
| 2 | Enhanced allelopathy and competitive ability of invasive plant Solidago canadensis in its introduced range显示文摘Aims Why invasive plants are more competitive in their introduced range than native range is still an unanswered question in plant invasion ecology.Here,we used the model invasive plant Solidago canaden-sis to test a hypothesis that enhanced production of allelopathic compounds results in greater competitive ability of invasive plants in the invaded range rather than in the native range.We also exam-ined the degree to which the allelopathy contributes increased com-petitive ability of S.canadensis in the invaded range.Methods We compared allelochemical production by S.canadensis growing in its native area(the USA)and invaded area(China)and also by populations that were collected from the two countries and grown together in a'common garden'greenhouse experiment.We also tested the allelopathic effects of S.canadensis collected from either the USA or China on the germination of Kummerowia striata(a native plant in China).Finally,we conducted a common garden,greenhouse experiment in which K.striata was grown in monocul-ture or with S.canadensis from the USA or China to test the effects of allopathy on plant-plant competition with suitable controls such as adding activated carbon to the soil to absorb the allelochemicals and thereby eliminating any corresponding allopathic effects.Important findings Allelochemical contents(total phenolics,total flavones and total saponins)and allelopathic effects were greater in S.canadensis sampled from China than those from the USA as demonstrated in a field survey and a common garden experiment.Inhibition of K.stri-ata germination using S.canadensis extracts or previously grown in soil was greater using samples from China than from the USA.The competitive ability of S.canadensis against K.striata was also greater for plants originating from China than those from the USA.Allelopathy could explain about 46%of the difference.These find-ings demonstrated that S.canadensis has evolved to be more allelo-pathic and competitive in the introduced range and that allelopathy significantly contributes to increased competitiveness for this inva-sive species. | Yongge Yuan Bing Wang Shanshan Zhang Jianjun Tang Cong Tu Shuijin Hu Jean W.H.Yong Xin Chen | 2013 | Journal of Plant Ecology2013，6，3： | 15 |
| 3 | 蓝舌病多克隆抗体C-ELISA检测方法的建立和比较研究显示文摘为建立一种检测成本低、操作简便的蓝舌病血清抗体监测方法,本研究通过制备群特异性的蓝舌病多克隆检测抗体和优化抗原固定技术,建立了蓝舌病多克隆抗体C-ELISA检测方法。通过对150份牛羊已知阴性血清的检测确定该检测方法的cut-off值为40%;对58份已知阳性血清样品同时进行中和实验和C-ELISA检测,检测结果经SPSS软件进行t检测统计分析,Sig.(双侧)=0.651,相关性0.912,相关性显著。对24个BTV血清型阳性血清,2份牛BVD阳性血清,2份羊口蹄疫阳性血清,2份羊痘阳性血清进行检测。结果表明,24个BTV血清型阳性血清为阳性,其他血清全部为阴性。对150份已知阴性血清和55份已知阳性血清用中和试验、美国VMRD公司试剂盒和本方法分别进行检测。结果表明,本检测方法与中和试验检测结果符合率达100%,进口试剂盒符合率为96.7%。 | 苗海生 李乐 廖德芳 杨永钦 李华春 | 2014 | 云南农业大学学报(自然科学版)2014，29，1： | 13 |
| 4 | Tele-Network Design Based on Queue Competition Algorithm显示文摘In this paper, we report research on how to design the tele-network. First of all, we defined the reliability of tele-network. According to the definition, we divide the whole reliability into two parts:the reliability of the mini-way and that of the whole system. Then we do algebra unintersection of the mini-way, deriving a function of reliability of tele-network. Also, we got a function of the cost of tele-network after analyzing the cost of arcs and points. Finally, we give a mathematical model to design a tele-network. For the algorithm, we define the distance of a network and adjacent area within certain boundaries . We present a new algorithm--Queue Competition Algorithm (QCA) based on the adjacent area . The QCA correlates sequence of fitnesses in their father-generations with hunting zone of mutation and the number of individuals generated by mutation, making the stronger fitness in a small zone converge at a local extreme value, but the weaker one takes the advantage of lots of individuals | Huang Zhang-can, Wan Li-jun, Tang Tao, Chen Zheng-xuState Key Laboratory of Software Engineering, Wuhan University, Wuhan 430072, Hubei, ChinaSchool of Material Science and Engineering, Wuhan University of Technology , Wuhan 430070, Hubei, ChinaSchool of Automation, Wuhan University of Technology, Wuhan 430070, Hubei, ChinaSchool of Science, Wuhan University of Technology, Wuhan 430070, Hubei, China | 2003 | Wuhan University Journal of Natural Sciences2003，8，S1： | 12 |
| 5 | The evolution of cooperation in asymmetric systems显示文摘Explaining the 'Tragedy of the Commons' of the evolution of cooperation remains one of the greatest problems for both biology and social science.Asymmetrical interaction,which is one of the most important characteristics of cooperative systems,has not been sufficiently considered in the existing models of the evolution of cooperation.Considering the inequality in the number and payoff between the cooperative actors and recipients in cooperation systems,discriminative density-dependent interference competition will occur in limited dispersal systems.Our model and simulation show that the local but not the global stability of a cooperative interaction can be maintained if the utilization of common resource remains unsaturated,which can be achieved by density-dependent restraint or competition among the cooperative actors.More intense density dependent interference competition among the cooperative actors and the ready availability of the common resource,with a higher intrinsic contribution ratio of a cooperative actor to the recipient,will increase the probability of cooperation.The cooperation between the recipient and the cooperative actors can be transformed into conflict and,it oscillates chaotically with variations of the affecting factors under different environmental or ecological conditions.The higher initial relatedness(i.e.similar to kin or reciprocity relatedness),which is equivalent to intrinsic contribution ratio of a cooperative actor to the recipient,can be selected for by penalizing less cooperative or cheating actors but rewarding cooperative individuals in asymmetric systems.The initial relatedness is a pivot but not the aim of evolution of cooperation.This explains well the direct conflict observed in almost all cooperative systems. | WANG RuiWu1 & SHI Lei2 1 State Key Laboratory of Genetic Resources and Evolution,Kunming Institute of Zoology,Chinese Academy of Science,Kunming 650223,China 2 Statistics and Mathematics College,Yunnan University of Finance and Economics,Kunming 650221,China | 2010 | Science China(Life Sciences)2010，53，1： | 11 |
| 6 | Storage reliability assessment model based on competition failure of multi-components in missile显示文摘The degradation data of multi-components in missile is derived by periodical testing. How to use these data to assess the storage reliability(SR) of the whole missile is a difficult problem in current research. An SR assessment model based on competition failure of multi-components in missile is proposed. By analyzing the missile life profile and its storage failure feature, the key components in missile are obtained and the characteristics voltage is assumed to be its key performance parameter. When the voltage testing data of key components in missile are available, a state space model(SSM) is applied to obtain the whole missile degradation state, which is defined as the missile degradation degree(DD). A Wiener process with the time-scale model(TSM) is applied to build the degradation failure model with individual variability and nonlinearity. The Weibull distribution and proportional risk model are applied to build an outburst failure model with performance degradation effect. Furthermore, a competition failure model with the correlation between degradation failure and outburst failure is proposed. A numerical example with a set of missiles in storage is analyzed to demonstrate the accuracy and superiority of the proposed model. | Yunxiang Chen Qiang Zhang Zhongyi Cai Lili Wang | 2017 | Journal of Systems Engineering and Electronics2017，28，3： | 9 |
| 7 | Product market competition,ultimate controlling structure and related party transactions显示文摘Previous studies have shown that product market competition has an important effect on corporate strategies and internal governance mechanisms. Using a sample of China's listed firms from 2004 to 2009, we explore the relationship between product market competition and normal related party transactions and find a significant positive relationship. In addition, we investigate the substitutive effect of product market competition and the cash flow rights owned by ultimate controlling shareholders on the extent of normal related party transactions. In particular, our results suggest a positive relationship between the ultimate controlling shareholders' cash flow rights and normal related party transactions that is strongest in noncompetitive industries and weakens as product market competition increases. | Shenglan Chen Kun Wang Xiaoxue Li | 2012 | China Journal of Accounting Research2012，，4： | 7 |
| 8 | A Memetic Algorithm With Competition for the Capacitated Green Vehicle Routing Problem显示文摘In this paper, a memetic algorithm with competition(MAC) is proposed to solve the capacitated green vehicle routing problem(CGVRP). Firstly, the permutation array called traveling salesman problem(TSP) route is used to encode the solution, and an effective decoding method to construct the CGVRP route is presented accordingly. Secondly, the k-nearest neighbor(k NN) based initialization is presented to take use of the location information of the customers. Thirdly, according to the characteristics of the CGVRP, the search operators in the variable neighborhood search(VNS) framework and the simulated annealing(SA) strategy are executed on the TSP route for all solutions. Moreover, the customer adjustment operator and the alternative fuel station(AFS) adjustment operator on the CGVRP route are executed for the elite solutions after competition. In addition, the crossover operator is employed to share information among different solutions. The effect of parameter setting is investigated using the Taguchi method of design-ofexperiment to suggest suitable values. Via numerical tests, it demonstrates the effectiveness of both the competitive search and the decoding method. Moreover, extensive comparative results show that the proposed algorithm is more effective and efficient than the existing methods in solving the CGVRP. | Ling Wang Jiawen Lu | 2019 | IEEE/CAA Journal of Automatica Sinica2019，6，2： | 7 |
| 9 | On Tariffs and the General Agreement on Tariffs and Trade (GATT)显示文摘 | 王鼎咏 | 1994 | Social Sciences in China1994，15，1： | 7 |
| 10 | 垄断行业和国有企业改革显示文摘被称为'垄断行业'的电力、电信、铁道、民航、邮政、公用、石油、军工等均为关系国计民生的重要行业和关键领域。30年来,这些行业不同程度地推进了政企分开、引入竞争和国企股份制等改革,促进了发展。上述行业或由于固有的自然垄断性质,或由于其外部性或战略重要性,应该保持国有经济的支配地位,根据行业具体情况决定竞争的程度。深化改革的目标是通过引进竞争和产权多元化,转变机制,增强活力,以增进社会福利和提高国家竞争力,而不是要国有经济退出这些领域。 | 高梁 | 2010 | 政治经济学评论2010，1，3： | 7 |
| 11 | Designing near-natural planting patterns for plantation forests in China显示文摘Background: China has a long tradition of managing planted forests. Different species of Populus, Eucalyptus, Larix, Cunninghamia and Pinus are planted to satisfy the local demand for wood products and provide ecological services at the same time. Evidence of the greater resilience of natural forests provides the motivation to develop asymmetric planting patterns, which is the focus of this study. We present a new method for designing plantation patterns that follow those observed in natural ecosystems and to maintain some regularity for operational convenience. Methods: Based on the uniform angle index, we analyzed the spatial structure of six natural forests in different regions of China. The uniform angle index describes the degree of spatial uniformity of the n nearest neighbors of a given reference tree. Accordingly, we identified all possible patterns of a neighborhood group within a regular planting pattern and developed a method to optimize planting point arrangements that contain some randomness as well as a minimum degree of regularity. Results:(1) There are 13 types of structural units in a regular planting, including seven random units, five even units and one cluster unit;(2) Five near-natural arrangements are presented with a minimum proportion of 50% of random units. These five arrangements represent a combination of regularity for operational convenience and asymmetry. Conclusions: The new planting patterns developed in this study are expected to increase the asymmetric competition and resilience of these important ecosystems. Some experimental plantings, based on our findings, have already been established, e.g., in Pinus tabulaeformis plantations in Tianshui, Gansu Province, and in a Populus deltoides plantation in Fangshan near Beijing. | Gongqiao Zhang Gangying Hui Yanbo Hu Zhonghua Zhao Xiuling Guan Klaus von Gadow Ganggang Zhang | 2019 | Forest Ecosystems2019，6，3： | 6 |
| 12 | China's Belt and Road Initiative:Perspectives from India显示文摘China "s Belt and Road Initiative (BRI) is often simplistically understood as beingopposed by lndia and supported by Pakistan. The reality on the ground is rather morecomplex. The emerging consensus in lndia appears to be that, far from being exclusivelyan economic and infrastructure development program, the BRI may be understood as along-term strategic initiative that seeks to convert China "s current economic might intodiplomatic influence. While attempts have been made by Beijing, the reflexive lndiansuspicion of Chinese international projection, including of China "s BRL has not yetbeen met by a coherent discourse designed to specifically address lndian concerns. Incontrast, in Pakistan, widespread acceptance of the importance and necessity of theChina-Pakistan Economic Corridor is increasingly coupled with concerns within sectorsof Pakistani society over the fairness, transparency and eventual economic outcomesof the project. Accordingly, this paper is divided into two parts: the first looks at howlndian analysts have viewed and responded to the Chinese discourse and arguments onthe BR1; the second considers the debate over the China-Pakistan Economic Corridorwithin Pakistan. | Jabin T. Jacob | 2017 | China & World Economy2017，25，5： | 5 |
| 13 | Timing is everything:does early and late germination favor invasions by herbaceous alien plants?显示文摘Aims Plant invasions represent a unique opportunity to study the mechanisms underlying community assembly rules and species distribution patterns.While a superior competitive ability has often been proposed as a major driver of successful plant invasions,its significance depends crucially on the timing of any competitive interaction.We assess whether a mismatch in germination phenology can favor the establishment of alien species,allowing them to exploit vacant niches where competition is low.As well as having important effects on the survival,growth and fitness of a species,asymmetric competition and potential soil legacies resulting from early or late germination can also impact on species recruitment.However,early or late germination comes at a cost,increases the risks of exposure to unfavorable conditions and requires an enhanced abiotic resistance if it is to lead to successful establishment.Important Findings While there are several anecdotal accounts of early and late ger-mination for invasive species,there are limited comparative data with resident species growing under natural conditions.Available evidence from grassland communities indicates that a short-term germination advantage or priority(few days/weeks)provides inva-sive species with a strong competitive advantage over native species and is a critical factor in many invasions.While the exploitation of periods of low competition is a plausible mechanism for the suc-cessful establishment of many invasive plants,direct evidence for this strategy is still scarce.This is particularly true with regard to the exploitation of late germination niches.Consequently,long-term comparative monitoring of the germination phenology of invasive and native plants in situ is needed to assess its significance in a range of ecosystems and its impact on community dynamics. | Margherita Gioria Petr Pyšek Bruce A.Osborne | 2018 | Journal of Plant Ecology2018，11，1： | 5 |
| 14 | Soil heterogeneity affects ramet placement of Hydrocotyle vulgaris显示文摘Aims Soil heterogeneity is common in natural habitats.It may trigger for-aging responses(placing more ramets and/or roots in nutrient-rich patches than in nutrient-poor patches)and further affect the growth of plants.However,the impact of soil heterogeneity on competitive interactions has been little tested.Methods We conducted a greenhouse experiment to investigate the effects of soil heterogeneity on intraspecific competition with a stolonif-erous herb Hydrocotyle vulgaris.We grew one(without com-petition)or nine ramets(with competition)of H.vulgaris under a homogeneous environment and two heterogeneous environ-ments differing in patch size(large or small patches).In the het-erogeneous treatment,the soil consisted of the same number of nutrient-rich and nutrient-poor patches arranged in a chessboard manner,and in the homogeneous treatment,the soil was an even mixture of the same amount of the nutrient-rich and the nutrient-poor soil.Important Findings Irrespective of intraspecific competition,H.vulgaris showed for-aging responses to soil heterogeneity in the large patch treatment,e.g.it produced significantly more biomass,ramets,aboveground mass and root mass in the nutrient-rich patches than in the nutrient-poor patches.In the small patch treatment,foraging responses were observed when intraspecific competition was present,but responses were not observed when there was no competition.However,we find a significant effect of soil heterogeneity on neither overall growth nor competitive intensity of H.vulgaris.Our results suggest that foraging responses to soil heterogeneity may not necessarily be adaptive and intraspecific competition may not be influenced by soil heterogeneity. | Bi-Cheng Dong Jiu-Zhong Wang Rui-Hua Liu Ming-Xiang Zhang Fang-Li Luo Fei-Hai Yu | 2015 | Journal of Plant Ecology2015，8，1： | 5 |
| 15 | “Work Units” and the Commodification of Housing: Observations on the Transition to a Market Economy with Chinese Characteristics显示文摘 | John R.Logan 边燕杰 关颖 卢汉龙 潘允康 | 1997 | Social Sciences in China1997，18，4： | 5 |
| 16 | GLOBAL ATTRACTIVITY IN A PERIODIC COMPETITION SYSTEM WITH FEEDBACK CONTROLS显示文摘WENGPEIXUAN(翁佩萱)(DepartmentofMathematics,SouthChinaNormalUniversity,Guangzhou510631,China)GLOBALATTRACTIVITYINAPERIODICCOMPET... | 翁佩萱 | 1996 | Acta Mathematicae Applicatae Sinica1996，12，1： | 5 |
| 17 | Activity patterns and resource partitioning: seven species at watering sites in the Altun Mountains, China显示文摘As part of a larger project to examine the richness and distribution of wildlife in Kumtag Desert area, we conducted camera trapping surveys during the period 2010–2012 at seven watering sites in an arid region of the Altun Mountains in western China. Information on activity patterns of the wild bactrian camel (Camelus ferus), kiang (Equus kiang), goitered gazelle (Gazella subgutturosa), argali (Ovis ammon), blue sheep (Pseudois nayaur), red fox (Vulpes vulpes), and wolf (Canis lupus) was obtained. We found that the wild camel, kiang, goitered gazelle, argali, and blue sheep were predominantly diurnal at watering sites, whereas red fox and wolf were nocturnal. Five herbivores partitioned the use of watering sites in a temporal manner to minimize the risk of predation by carnivores. The wild camel was the dominant herbivorous species at the watering sites. The kiang, goitered gazelle, argali, and blue sheep displayed adaptive water use by altering spatial or temporal patterns based on the presence or absence of wild camel, to minimize the risk of interspecific strife. These results are suggestive of the differences in activity patterns that might modulate water partitioning by different species, and provide insights for the development of conservation strategies for integrated species and decisions regarding water development in the Altun Mountains. | XUE Yadong LI Jia SAGEN Guli ZHANG Yu DAI Yunchuan LI Diqiang | 2018 | Journal of Arid Land2018，10，6： | 4 |
| 18 | Cooperation and Competition Strategy Analysis of Decision-Making Units Based on Efficiency Game显示文摘Data envelopment analysis(DEA)method based on game theory effectively ranks the decisionmaking units(DMUs)by the view of cooperation or competition.The DEA method based on partial ordered set theory depicts the relationships among DMUs.However,these methods are unable to reveal the complex cooperation and competition relationships among DMUs.In this paper,an optimal model for DMU group game strategy is proposed based on the generalized DEA method and game theory.According to this model,we can effectively depict the efficiency change of DMUs.Moreover,the effect of various game relationships on individual and the union of DMUs can be characterized.It is of positive significance for decision makers to find partners and moderate the cooperation and competition situation of their competitors.Finally,the cooperation and competition relationships of 9 express enterprises in a certain area in China are analyzed by using the method proposed in this paper. | Li Cao Zhanxin Ma Muren | 2020 | Journal of Systems Science and Systems Engineering2020，29，2： | 4 |
| 19 | Spatial dynamic patterns of saltmarsh vegetation in southern Hangzhou Bay:Exotic and native species显示文摘A saltmarsh has developed rapidly on the mudflat of Andong Shoal,in southern Hangzhou Bay,over the last decade since embankment.The saltmarsh vegetation changes are driven by both sediment dynamic conditions and the competition between the exotic species Spartina alterniflora(S.alterniflora) and the native species Scirpus mariqueter(S.mariqueter).This study attempted to investigate large-scale spatial variations in the exotic and native species,by analyzing and interpreting a time series(2016-2018) of high-resolution(less than 1 m) remote sensing images.The total area of the saltmarsh increased at a rate of 1.07 km^2/year,due to the accretion of the whole tidal flat.The spatial patterns revealed a new bimodal pattern for S.alterniflora invasion.S.alterniflora expanded over the upper to middle saltmarsh at a rate of1.68 km2/year.However,the S.alterniflora patches at the seaward edge expanded at a negative rate of-0.005 km^2/year,indicating a different pattern in competition:S.alterniflora had more advantages in the upper saltmarsh,while S.mariqueter had more advantages in the pioneer zone with low elevation.Consequently,S.alterniflora mainly established new habitats by invading S.mariqueter in the middle saltmarsh,but S.mariqueter occupied the bare mudflat for tradeoff.Our results aindicated that the interspecific competition result between S.alterniflora and S.mariqueter depended on elevation,and low elevation might create a favorable environment for S.mariqueter to win the competition with exotic species.This finding could be applied to future invasive species control and saltmarsh management. | Si-long Huang Yi-ning Chen Yan Li | 2020 | Water Science and Engineering2020，13，1： | 3 |
| 20 | Pledgee competition, strategic disclosure, and future crash risk显示文摘We investigate whether pledgee competition affects the disclosure choice of firms whose controlling shareholders pledge their shares.We find that pledgee competition is positively related to pledge firms’ annual report tone management.This positive relationship is stronger for pledge firms with lower credit quality and non-state-owned enterprise pledge firms.Further corroborating our results, higher pledgee competition increases the future crash risk of pledge firms.Collectively, our results suggest that competition pressure induces pledgees to lower their monitoring incentives to remain competitive in the marketplace, thus leading to pledge firms’ bad news hoarding behavior. | Xiaoxi Li Jing Liu Kemin Wang | 2019 | China Journal of Accounting Research2019，，3： | 3 |
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