In this paper,we propose a Multi-token Sector Antenna Neighbor Discovery(M-SAND)protocol to enhance the efficiency of neighbor discovery in asynchronous directional ad hoc networks.The central concept of our work invo...In this paper,we propose a Multi-token Sector Antenna Neighbor Discovery(M-SAND)protocol to enhance the efficiency of neighbor discovery in asynchronous directional ad hoc networks.The central concept of our work involves maintaining multiple tokens across the network.To prevent mutual interference among multi-token holders,we introduce the time and space non-interference theorems.Furthermore,we propose a master-slave strategy between tokens.When the master token holder(MTH)performs the neighbor discovery,it decides which 1-hop neighbor is the next MTH and which 2-hop neighbors can be the new slave token holders(STHs).Using this approach,the MTH and multiple STHs can simultaneously discover their neighbors without causing interference with each other.Building on this foundation,we provide a comprehensive procedure for the M-SAND protocol.We also conduct theoretical analyses on the maximum number of STHs and the lower bound of multi-token generation probability.Finally,simulation results demonstrate the time efficiency of the M-SAND protocol.When compared to the QSAND protocol,which uses only one token,the total neighbor discovery time is reduced by 28% when 6beams and 112 nodes are employed.展开更多
In clustering algorithms,the selection of neighbors significantly affects the quality of the final clustering results.While various neighbor relationships exist,such as K-nearest neighbors,natural neighbors,and shared...In clustering algorithms,the selection of neighbors significantly affects the quality of the final clustering results.While various neighbor relationships exist,such as K-nearest neighbors,natural neighbors,and shared neighbors,most neighbor relationships can only handle single structural relationships,and the identification accuracy is low for datasets with multiple structures.In life,people’s first instinct for complex things is to divide them into multiple parts to complete.Partitioning the dataset into more sub-graphs is a good idea approach to identifying complex structures.Taking inspiration from this,we propose a novel neighbor method:Shared Natural Neighbors(SNaN).To demonstrate the superiority of this neighbor method,we propose a shared natural neighbors-based hierarchical clustering algorithm for discovering arbitrary-shaped clusters(HC-SNaN).Our algorithm excels in identifying both spherical clusters and manifold clusters.Tested on synthetic datasets and real-world datasets,HC-SNaN demonstrates significant advantages over existing clustering algorithms,particularly when dealing with datasets containing arbitrary shapes.展开更多
Against the backdrop of the international political and economic configuration featuring that“the East is rising and the West is declining”,relations between China and its neighboring countries enjoy steady developm...Against the backdrop of the international political and economic configuration featuring that“the East is rising and the West is declining”,relations between China and its neighboring countries enjoy steady development in general.However,the return of the Cold War mentality,rampant protectionism and prominent security governance issues have seriously threatened peace and stability in China’s neighboring region.展开更多
In unmanned aerial vehicle(UAV)networks,the high mobility of nodes leads to frequent changes in network topology,which brings challenges to the neighbor discovery(ND)for UAV networks.Integrated sensing and communicati...In unmanned aerial vehicle(UAV)networks,the high mobility of nodes leads to frequent changes in network topology,which brings challenges to the neighbor discovery(ND)for UAV networks.Integrated sensing and communication(ISAC),as an emerging technology in 6G mobile networks,has shown great potential in improving communication performance with the assistance of sensing information.ISAC obtains the prior information about node distribution,reducing the ND time.However,the prior information obtained through ISAC may be imperfect.Hence,an ND algorithm based on reinforcement learning is proposed.The learning automaton(LA)is applied to interact with the environment and continuously adjust the probability of selecting beams to accelerate the convergence speed of ND algorithms.Besides,an efficient ND algorithm in the neighbor maintenance phase is designed,which applies the Kalman filter to predict node movement.Simulation results show that the LA-based ND algorithm reduces the ND time by up to 32%compared with the Scan-Based Algorithm(SBA),which proves the efficiency of the proposed ND algorithms.展开更多
In order to reveal the complex network characteristics and evolution principle of China aviation network,the probability distribution and evolution trace of arithmetic average of edge vertices nearest neighbor average...In order to reveal the complex network characteristics and evolution principle of China aviation network,the probability distribution and evolution trace of arithmetic average of edge vertices nearest neighbor average degree values of China aviation network were studied based on the statistics data of China civil aviation network in 1988,1994,2001,2008 and 2015.According to the theory and method of complex network,the network system was constructed with the city where the airport was located as the network node and the route between cities as the edge of the network.Based on the statistical data,the arithmetic averages of edge vertices nearest neighbor average degree values of China aviation network in 1988,1994,2001,2008 and 2015 were calculated.Using the probability statistical analysis method,it was found that the arithmetic average of edge vertices nearest neighbor average degree values had the probability distribution of normal function and the position parameters and scale parameters of the probability distribution had linear evolution trace.展开更多
Plants have developed sophisticated mechanisms to survive in dynamic environments.Plants can communicate via volatile organic compounds(VOCs)to warn neighboring plants of threats.In most cases,VOCs act as positive reg...Plants have developed sophisticated mechanisms to survive in dynamic environments.Plants can communicate via volatile organic compounds(VOCs)to warn neighboring plants of threats.In most cases,VOCs act as positive regulators of plant defense.However,the communication and role of volatiles in response to drought stress are poorly understood.Here,we showed that tea plants release numerous VOCs.Among them,methyl salicylate(MeSA),benzyl alcohol,and phenethyl alcohol markedly increased under drought stress.Interestingly,further experiments revealed that drought-induced MeSA lowered the abscisic acid(ABA)content in neighboring plants by reducing 9-cis-epoxycarotenoid dioxygenase(NCED)gene expression,resulting in inhibition of stomatal closure and ultimately decreasing early drought tolerance in neighboring plants.Exogenous application of ABA reduced the wilting of tea plants caused by MeSA exposure.Exposure of Nicotiana benthamiana to MeSA also led to severe wilting,indicating that the ability of drought-induced MeSA to reduce early drought tolerance in neighboring plants may be conserved in other plant species.Taken together,these results provide evidence that drought-induced volatiles can reduce early drought tolerance in neighboring plants and lay a novel theoretical foundation for optimizing plant density and spacing.展开更多
The Deep Seismic Sounding( DSS) projects carried out from the 1970 s in the lower Yangtze region and its neighboring area were reviewed in this paper,then the basic wave group features of those wide angle reflection /...The Deep Seismic Sounding( DSS) projects carried out from the 1970 s in the lower Yangtze region and its neighboring area were reviewed in this paper,then the basic wave group features of those wide angle reflection / refraction record sections,and of the crustal structure are summarized. It shows that there were in total five clear wave groups on the record sections,which include the first arrival Pg,the reflection P1 from the bottom interface of the upper crust,the reflection P3 from the bottom interface of the middle crust,the strong reflection Pm from the Moho boundary,and the refraction Pn from uppermost mantle. In general,these phases are easily consistently traced and compared,despite some first arrivals being delayed or arriving earlier than normal due to the shallow sedimentary cover or bedrocks. In particular,in the Dabie Mountain region the seismic events of a few gathered shots always have weak reflection energy,are twisted,or exhibit disorganized waveforms, which could be attributed to the disruption variations of reflection depth,the broken Moho,and the discontinuity of the reflection boundary within crust. The regional crustal structures are composed of the upper,middle and lower crust,of which the middle and lower layers can be divided into two weak reflection ones. The crustal thickness of the North China and Yangtze platform are 30km- 36 km,and the Moho exhibits a flat geometry despite some local uplifts. The average pressure velocity in lower crust beneath this two tectonic area is 6. 7 ± 0. 3km / s. Nevertheless,beneath the Dabieshan area the crustal thickness is 32km- 41 km,the Moho bends down sharply andtakes an abrupt 4km- 7km dislocation in the vertical direction. The average pressure velocity in the lower crust beneath the Dabieshan area is 6. 8 ± 0. 2km / s.展开更多
After the publication of this article 1,the authors became aware that the word of“tea”was not mentioned in the title.To make the title clear and complete,the word‘tea’is added to the title.
Zipf's approach in linguistics is utilized to analyze the statistical features of frequency and correlation of 16 nearest neighboring nucleotides (AA, AC, AG, …, TT) in 12 human chro- mosomes (Y, 22, 21, 20, 19, ...Zipf's approach in linguistics is utilized to analyze the statistical features of frequency and correlation of 16 nearest neighboring nucleotides (AA, AC, AG, …, TT) in 12 human chro- mosomes (Y, 22, 21, 20, 19, 18, 17, 16, 15, 14, 13, and 12). It is found that these statistical features of nearest neighboring nucleotides in human genome: (i) the frequency distribution is a linear function, and (ii) the correlation distribution is an inverse function. The coefficients of the linear function and inverse function depend on the GC content. It proposes the correlation distribution of nearest neighboring nucleotides for the first time and extends the descriptor about nearest neighboring nueleotides.展开更多
In order to determine the influence of shearer's cutting and neighboring shields' advance on the support resistance variation, leg pressure data of all 235 shields in the panel LW61 of Cumberland coal mine wer...In order to determine the influence of shearer's cutting and neighboring shields' advance on the support resistance variation, leg pressure data of all 235 shields in the panel LW61 of Cumberland coal mine were analyzed. The results show that the relationship between the leg pressure increment and the distance from shield to front drum of shearer is a quadratic function and that the higher leg pressure increment before shield advance tends to be related to adverse roof conditions. In addition, the three proposed leg pressure increment-related parameters and the three traditional parameters(time-weighted average pressure, setting pressure, and final pressure) of approximately 32000 shield supporting cycles were calculated by a self-developed software package to analyze the correlation between them. The results show that there is a powerful connection between them, and that the three proposed leg pressure increment-related parameters could be used as the indexes to evaluate the interaction between shields and the roof, and to identify the periodic weighting.展开更多
In the present experiment,we investigate the effects of orthodontic tooth rotation onneighboring teeth and periodontal tissues.The second maxillary incisors of 16 randomly selecteddogs were subjected to rotation at a ...In the present experiment,we investigate the effects of orthodontic tooth rotation onneighboring teeth and periodontal tissues.The second maxillary incisors of 16 randomly selecteddogs were subjected to rotation at a magnitude of 100 grams and a moment of 550 g·mm in a du-ration of 3 to 56 days.Then sections were prepared for histological examination.The findings re-vealed that,due to tooth rotation,neighboring teeth were drifted and rotated(82%),and therewere disarrangement and hyalinization of the periodontal ligament(88%),remodeling of the pe-riodontium(86%)and root resorption(32%)were also observed.These results demonstratethat tooth rotation may exert marked effects on neighboring teeth and periodontal tissues,whichmay be of important clinical significance.展开更多
By means of Logic symmetric relation,the single neighboring Logic path for Ndimensions Boolean ordered set is solved.A new method of determining any logic neighboringsubset in limited dimension is proposed.Its results...By means of Logic symmetric relation,the single neighboring Logic path for Ndimensions Boolean ordered set is solved.A new method of determining any logic neighboringsubset in limited dimension is proposed.Its results are intuitional and realizable for computer.展开更多
The Indochina Peninsula is of special and important significance to China's geopolitical strategy,which is the foothold of China's strategy in Southeast Asia and even the whole Asia-Pacific region,as well as t...The Indochina Peninsula is of special and important significance to China's geopolitical strategy,which is the foothold of China's strategy in Southeast Asia and even the whole Asia-Pacific region,as well as the strategic springboard of*China s global development.In 2016,China led the establishment of the Lancang-Mekong Cooperation mechanism,and achieved remarkable results in terms of institutional development,project implementation and the construction of international relations among member states in the short term.The establishment and rapid development of the Lancang-Mekong Cooperation is based on member states,strong willingness to cooperate.It also benefits from the rational design of their institutional structures,geographical advantages,strong and complementary economies,and close sociocultural similarities.On the other hand,the further development of the Lancang?Mekong Cooperation is facing many risks and challenges as a result of the complexities of the internal environment of the Indochina Peninsula and the geopolitical competition of extraterritorial forces in the region.In this regard,China should make more efforts to improve relevant institutional arrangements for the Lancang-Mekong Cooperation,broaden the areas and enrich the content of cooperation,coordinate with extraterritorial forces and increase the number of stakeholders.展开更多
Recently manifold learning algorithm for dimensionality reduction attracts more and more interests, and various linear and nonlinear,global and local algorithms are proposed. The key step of manifold learning algorith...Recently manifold learning algorithm for dimensionality reduction attracts more and more interests, and various linear and nonlinear,global and local algorithms are proposed. The key step of manifold learning algorithm is the neighboring region selection. However,so far for the references we know,few of which propose a generally accepted algorithm to well select the neighboring region. So in this paper,we propose an adaptive neighboring selection algorithm,which successfully applies the LLE and ISOMAP algorithms in the test. It is an algorithm that can find the optimal K nearest neighbors of the data points on the manifold. And the theoretical basis of the algorithm is the approximated curvature of the data point on the manifold. Based on Riemann Geometry,Jacob matrix is a proper mathematical concept to predict the approximated curvature. By verifying the proposed algorithm on embedding Swiss roll from R3 to R2 based on LLE and ISOMAP algorithm,the simulation results show that the proposed adaptive neighboring selection algorithm is feasible and able to find the optimal value of K,making the residual variance relatively small and better visualization of the results. By quantitative analysis,the embedding quality measured by residual variance is increased 45. 45% after using the proposed algorithm in LLE.展开更多
In the international community,the internal ethnic issues of one country can easily spread out of its borders through the impact of internal and external factors to affect the national security of other countries,know...In the international community,the internal ethnic issues of one country can easily spread out of its borders through the impact of internal and external factors to affect the national security of other countries,known as the spillover effect.Presently,the ethnic issues of China's neighboring countries that have real consequences on the country's national security break down mainly into four types:the internal ethnic conflict,the transnational ethnic issue,the issues related with immigrants and the collaboration of the Three Forces.The risk of spillover can be summed up according to the intensity of its effect in five categories:infiltration,springboard,spillover,immigration and harassment.As diverse ethnic issues of the neighboring countries have different effects on China's national security,the Chinese government must grasp the core element of each issue to formulate specific policies.展开更多
Seismic pounding phenomena, particularly the collision of neighboring buildings under long-period ground motion, are becoming a significant issue in Japan. We focused on a specific apartment structure called the Nuevo...Seismic pounding phenomena, particularly the collision of neighboring buildings under long-period ground motion, are becoming a significant issue in Japan. We focused on a specific apartment structure called the Nuevo Leon buildings in the Tlatelolco district of Mexico City, which consisted of three similar buildings built consecutively with narrow expansion joints between the buildings. Two out of the three buildings collapsed completely in the 1985 Mexican earthquake. Using a finite element code based on the adaptively shifted integration (ASI)-Gauss technique, a seismic pounding analysis is performed on a simulated model of the Nuevo Leon buildings to understand the impact and collapse behavior of structures built near each other. The numerical code used in the analysis provides a higher computational efficiency than the conventional code for this type of problem and enables us to address dynamic behavior with strong nonlinearities, including phenomena such as member fracture and elemental contact. Contact release and recontact algorithms are developed and implemented in the code to understand the complex behaviors of structural members during seismic pounding and the collapse sequence. According to the numerical results, the collision of the buildings may be a result of the difference of natural periods between the neighboring buildings. This difference was detected in similar buildings from the damages caused by previous earthquakes. By setting the natural period of the north building to be 25% longer than the other periods, the ground motion, which hada relatively long period of 2 s, first caused the collision between the north and the center buildings. This collision eventually led to the collapse of the centerbuilding, followed by the destruction of the north building.展开更多
Plants respond differently to the identity of their neighbors,such as their sex and kinship,showing plasticity in their traits.However,how the functional traits of dioecious trees are shaped by the recognition of neig...Plants respond differently to the identity of their neighbors,such as their sex and kinship,showing plasticity in their traits.However,how the functional traits of dioecious trees are shaped by the recognition of neighbors with different sex and kinship remains unknown.In this study,we set up an experiment with different kin/nonkin and inter/intrasexual combinations for a dioecious tree species,Diospyros morrisiana.The results showed that plants grew better with nonkin and intrasexual neighbors than with kin and intersexual neighbors.Kin combinations had significantly shorter root length in the resource-overlapping zone than nonkin combinations,suggesting that kin tended to reduce competition by adjusting their root distribution,especially among female siblings.Our study suggested that the seedling growth of D.morrisiana was affected by both the relatedness and sexual identity of neighboring plants.Further analysis by gas chromatography-mass spectrometry showed that the root exudate composition of female seedlings differed from that of male seedlings.Root exudates may play important roles in sex competition in dioecious plants.This study indicates that sex-specific competition and kin recognition interact and co-shape the traits of D.morrisiana seedlings,while intrasexual and nonkin neighbors facilitate the growth of seedlings.Our study implies that kin-and sex-related interactions depend on different mechanisms,kin selection,and niche partitioning,respectively.These results are critical for understanding how species coexist and how traits are shaped in nature.展开更多
To overcome the problem of existing neighboring access point (AP) discovery methods in WLAN, for example they (PnP) of mul proposed. Us can not provide the accurate neighboring APs information needed for the Plug-...To overcome the problem of existing neighboring access point (AP) discovery methods in WLAN, for example they (PnP) of mul proposed. Us can not provide the accurate neighboring APs information needed for the Plug-and-Play ti-mode APs, three kinds of neighboring AP discovery and information exchange methods are ing these three neighboring AP discovery methods, passive discovery method, active discovery method and station assistant discovery method, the multi-mode AP can discover all neighboring APs and obtain needed information. We further propose two whole process flows, which combine three discovery methods in different manner, to achieve different goals. One process flow is to discover the neighboring AP as fast as possible, called fast discovery process flow. The other is to discover the neighboring AP with minimal interference to neighboring and accuracy of the method is confirmed APs, called the minimal interference process flow. The validity by the simulation.展开更多
The binding energy and generalized stacking-fault energy (GSFE) are two critical interface properties of two dimensional layered materials, and it is still unclear how neighboring layers affect the interface energy of...The binding energy and generalized stacking-fault energy (GSFE) are two critical interface properties of two dimensional layered materials, and it is still unclear how neighboring layers affect the interface energy of adjacent layers. Here, we investigate the effect of neighboring layers by comparing the differences of binding energy and GSFE between trilayer heterostructures (graphene/graphene/graphene, graphene/graphene/boron nitride,boron nitride/graphene/boron nitride) and bilayer heterostructures (graphene/graphene,graphene/boron nitride) using density functional theory. The binding energy of the adjacent layers changes from -2.3% to 22.55% due to the effect of neighboring layer, with a very small change of the interlayer distance. Neighboring layers also make a change from -2% to 10% change the GSFE, depending on the property of the interface between adjacent layers. In addition, a new simple expression is proven to describe the GSFE landscape of graphene-like structure with high accuracy.展开更多
With the deepening of globalization,geographically speaking,East Asian countries have proceeded from their respective realist positions and tried to promote the successful practice of economic cooperation between coun...With the deepening of globalization,geographically speaking,East Asian countries have proceeded from their respective realist positions and tried to promote the successful practice of economic cooperation between countries after the Cold War into a discussion of new regionalism in East Asia and Asia-Pacificism.Although the prototype of the“East Asia Community”led by Association of Southeast Asian Nations(ASEAN)gradually emerged,the successful practice of the East Asia Summit proved that the low-binding regional integration model led by ASEAN has a high probability of becoming a classic sample of the“East Asia Community”.It not only maintains regional stability,promotes regional cooperation,shapes regional norms,but also builds a collective identity within the region.However,in today’s world,isolationism which takes the supremacy of national interests as the supremacy has risen.It is difficult to internalize the value identity into a super-national model that breaks through the principles of realism,breakthroughs in interests,and the power framework.The thorny issues pose various challenges to the nation-states in the region trying to integrate into regional integration.The openness of East Asian regionalism has led to the persistent illness of its generalization.In the context of insufficient political mutual trust among regional countries,intensified competition among major powers,and continued weakening of ASEAN leadership,it is often prone to controversy and doubt when proposing new cooperation initiatives or ideas.The idea of the“East Asia Community”that once guided East Asian cooperation and was temporarily ignored now is still the most realistic choice.Although the theoretical construction and practical roads of East Asian regionalism are full of thorns,difficulties coexist with opportunities.With the extensive participation of countries in the region,the optimization and reconstruction of the East Asian cooperation model will be worth looking forward to.展开更多
基金supported in part by the National Natural Science Foundations of CHINA(Grant No.61771392,No.61771390,No.61871322 and No.61501373)Science and Technology on Avionics Integration Laboratory and the Aeronautical Science Foundation of China(Grant No.201955053002 and No.20185553035)。
文摘In this paper,we propose a Multi-token Sector Antenna Neighbor Discovery(M-SAND)protocol to enhance the efficiency of neighbor discovery in asynchronous directional ad hoc networks.The central concept of our work involves maintaining multiple tokens across the network.To prevent mutual interference among multi-token holders,we introduce the time and space non-interference theorems.Furthermore,we propose a master-slave strategy between tokens.When the master token holder(MTH)performs the neighbor discovery,it decides which 1-hop neighbor is the next MTH and which 2-hop neighbors can be the new slave token holders(STHs).Using this approach,the MTH and multiple STHs can simultaneously discover their neighbors without causing interference with each other.Building on this foundation,we provide a comprehensive procedure for the M-SAND protocol.We also conduct theoretical analyses on the maximum number of STHs and the lower bound of multi-token generation probability.Finally,simulation results demonstrate the time efficiency of the M-SAND protocol.When compared to the QSAND protocol,which uses only one token,the total neighbor discovery time is reduced by 28% when 6beams and 112 nodes are employed.
基金This work was supported by Science and Technology Research Program of Chongqing Municipal Education Commission(KJZD-M202300502,KJQN201800539).
文摘In clustering algorithms,the selection of neighbors significantly affects the quality of the final clustering results.While various neighbor relationships exist,such as K-nearest neighbors,natural neighbors,and shared neighbors,most neighbor relationships can only handle single structural relationships,and the identification accuracy is low for datasets with multiple structures.In life,people’s first instinct for complex things is to divide them into multiple parts to complete.Partitioning the dataset into more sub-graphs is a good idea approach to identifying complex structures.Taking inspiration from this,we propose a novel neighbor method:Shared Natural Neighbors(SNaN).To demonstrate the superiority of this neighbor method,we propose a shared natural neighbors-based hierarchical clustering algorithm for discovering arbitrary-shaped clusters(HC-SNaN).Our algorithm excels in identifying both spherical clusters and manifold clusters.Tested on synthetic datasets and real-world datasets,HC-SNaN demonstrates significant advantages over existing clustering algorithms,particularly when dealing with datasets containing arbitrary shapes.
文摘Against the backdrop of the international political and economic configuration featuring that“the East is rising and the West is declining”,relations between China and its neighboring countries enjoy steady development in general.However,the return of the Cold War mentality,rampant protectionism and prominent security governance issues have seriously threatened peace and stability in China’s neighboring region.
基金supported in part by the Fundamental Research Funds for the Central Universities under Grant No.2024ZCJH01in part by the National Natural Science Foundation of China(NSFC)under Grant No.62271081in part by the National Key Research and Development Program of China under Grant No.2020YFA0711302.
文摘In unmanned aerial vehicle(UAV)networks,the high mobility of nodes leads to frequent changes in network topology,which brings challenges to the neighbor discovery(ND)for UAV networks.Integrated sensing and communication(ISAC),as an emerging technology in 6G mobile networks,has shown great potential in improving communication performance with the assistance of sensing information.ISAC obtains the prior information about node distribution,reducing the ND time.However,the prior information obtained through ISAC may be imperfect.Hence,an ND algorithm based on reinforcement learning is proposed.The learning automaton(LA)is applied to interact with the environment and continuously adjust the probability of selecting beams to accelerate the convergence speed of ND algorithms.Besides,an efficient ND algorithm in the neighbor maintenance phase is designed,which applies the Kalman filter to predict node movement.Simulation results show that the LA-based ND algorithm reduces the ND time by up to 32%compared with the Scan-Based Algorithm(SBA),which proves the efficiency of the proposed ND algorithms.
文摘In order to reveal the complex network characteristics and evolution principle of China aviation network,the probability distribution and evolution trace of arithmetic average of edge vertices nearest neighbor average degree values of China aviation network were studied based on the statistics data of China civil aviation network in 1988,1994,2001,2008 and 2015.According to the theory and method of complex network,the network system was constructed with the city where the airport was located as the network node and the route between cities as the edge of the network.Based on the statistical data,the arithmetic averages of edge vertices nearest neighbor average degree values of China aviation network in 1988,1994,2001,2008 and 2015 were calculated.Using the probability statistical analysis method,it was found that the arithmetic average of edge vertices nearest neighbor average degree values had the probability distribution of normal function and the position parameters and scale parameters of the probability distribution had linear evolution trace.
基金This work was financially supported by the National Natural Science Foundation of China(31961133030,31870678,32022076)the Science Fund for Distinguished Young Scientists of Anhui Province(1908085J12)the Deutsche Forschungsgemeinschaft(SCHW634/32-1 and SCHW634/34-1).
文摘Plants have developed sophisticated mechanisms to survive in dynamic environments.Plants can communicate via volatile organic compounds(VOCs)to warn neighboring plants of threats.In most cases,VOCs act as positive regulators of plant defense.However,the communication and role of volatiles in response to drought stress are poorly understood.Here,we showed that tea plants release numerous VOCs.Among them,methyl salicylate(MeSA),benzyl alcohol,and phenethyl alcohol markedly increased under drought stress.Interestingly,further experiments revealed that drought-induced MeSA lowered the abscisic acid(ABA)content in neighboring plants by reducing 9-cis-epoxycarotenoid dioxygenase(NCED)gene expression,resulting in inhibition of stomatal closure and ultimately decreasing early drought tolerance in neighboring plants.Exogenous application of ABA reduced the wilting of tea plants caused by MeSA exposure.Exposure of Nicotiana benthamiana to MeSA also led to severe wilting,indicating that the ability of drought-induced MeSA to reduce early drought tolerance in neighboring plants may be conserved in other plant species.Taken together,these results provide evidence that drought-induced volatiles can reduce early drought tolerance in neighboring plants and lay a novel theoretical foundation for optimizing plant density and spacing.
基金funded by the Special Public Welfare Industry Research of China Earthquake Administration(201408023)Academician Chen Yong Workstation Special Funds of Yunnan Province and Natural Science Foundation of China(41374062,41174075)
文摘The Deep Seismic Sounding( DSS) projects carried out from the 1970 s in the lower Yangtze region and its neighboring area were reviewed in this paper,then the basic wave group features of those wide angle reflection / refraction record sections,and of the crustal structure are summarized. It shows that there were in total five clear wave groups on the record sections,which include the first arrival Pg,the reflection P1 from the bottom interface of the upper crust,the reflection P3 from the bottom interface of the middle crust,the strong reflection Pm from the Moho boundary,and the refraction Pn from uppermost mantle. In general,these phases are easily consistently traced and compared,despite some first arrivals being delayed or arriving earlier than normal due to the shallow sedimentary cover or bedrocks. In particular,in the Dabie Mountain region the seismic events of a few gathered shots always have weak reflection energy,are twisted,or exhibit disorganized waveforms, which could be attributed to the disruption variations of reflection depth,the broken Moho,and the discontinuity of the reflection boundary within crust. The regional crustal structures are composed of the upper,middle and lower crust,of which the middle and lower layers can be divided into two weak reflection ones. The crustal thickness of the North China and Yangtze platform are 30km- 36 km,and the Moho exhibits a flat geometry despite some local uplifts. The average pressure velocity in lower crust beneath this two tectonic area is 6. 7 ± 0. 3km / s. Nevertheless,beneath the Dabieshan area the crustal thickness is 32km- 41 km,the Moho bends down sharply andtakes an abrupt 4km- 7km dislocation in the vertical direction. The average pressure velocity in the lower crust beneath the Dabieshan area is 6. 8 ± 0. 2km / s.
文摘After the publication of this article 1,the authors became aware that the word of“tea”was not mentioned in the title.To make the title clear and complete,the word‘tea’is added to the title.
基金ACKNOWLEDGMENTS This work was supported by the National Natural Science Foundation of China (No.20173023 and No.90203012) and the Specialized Research Fund for the Doctoral Program of Higher Education of China
文摘Zipf's approach in linguistics is utilized to analyze the statistical features of frequency and correlation of 16 nearest neighboring nucleotides (AA, AC, AG, …, TT) in 12 human chro- mosomes (Y, 22, 21, 20, 19, 18, 17, 16, 15, 14, 13, and 12). It is found that these statistical features of nearest neighboring nucleotides in human genome: (i) the frequency distribution is a linear function, and (ii) the correlation distribution is an inverse function. The coefficients of the linear function and inverse function depend on the GC content. It proposes the correlation distribution of nearest neighboring nucleotides for the first time and extends the descriptor about nearest neighboring nueleotides.
基金provided by the National High Technology Research and Development Program of China(No.2012AA062100)the Program for New Century Excellent Talents in University of China(No.NCET-10-0770)
文摘In order to determine the influence of shearer's cutting and neighboring shields' advance on the support resistance variation, leg pressure data of all 235 shields in the panel LW61 of Cumberland coal mine were analyzed. The results show that the relationship between the leg pressure increment and the distance from shield to front drum of shearer is a quadratic function and that the higher leg pressure increment before shield advance tends to be related to adverse roof conditions. In addition, the three proposed leg pressure increment-related parameters and the three traditional parameters(time-weighted average pressure, setting pressure, and final pressure) of approximately 32000 shield supporting cycles were calculated by a self-developed software package to analyze the correlation between them. The results show that there is a powerful connection between them, and that the three proposed leg pressure increment-related parameters could be used as the indexes to evaluate the interaction between shields and the roof, and to identify the periodic weighting.
文摘In the present experiment,we investigate the effects of orthodontic tooth rotation onneighboring teeth and periodontal tissues.The second maxillary incisors of 16 randomly selecteddogs were subjected to rotation at a magnitude of 100 grams and a moment of 550 g·mm in a du-ration of 3 to 56 days.Then sections were prepared for histological examination.The findings re-vealed that,due to tooth rotation,neighboring teeth were drifted and rotated(82%),and therewere disarrangement and hyalinization of the periodontal ligament(88%),remodeling of the pe-riodontium(86%)and root resorption(32%)were also observed.These results demonstratethat tooth rotation may exert marked effects on neighboring teeth and periodontal tissues,whichmay be of important clinical significance.
文摘By means of Logic symmetric relation,the single neighboring Logic path for Ndimensions Boolean ordered set is solved.A new method of determining any logic neighboringsubset in limited dimension is proposed.Its results are intuitional and realizable for computer.
基金a major research project funded by the National Social Science Foundation,titled “Research on the Construction of the Belt and Road Initiative and Neighboring Diplomacy”(Project No.2017010186)
文摘The Indochina Peninsula is of special and important significance to China's geopolitical strategy,which is the foothold of China's strategy in Southeast Asia and even the whole Asia-Pacific region,as well as the strategic springboard of*China s global development.In 2016,China led the establishment of the Lancang-Mekong Cooperation mechanism,and achieved remarkable results in terms of institutional development,project implementation and the construction of international relations among member states in the short term.The establishment and rapid development of the Lancang-Mekong Cooperation is based on member states,strong willingness to cooperate.It also benefits from the rational design of their institutional structures,geographical advantages,strong and complementary economies,and close sociocultural similarities.On the other hand,the further development of the Lancang?Mekong Cooperation is facing many risks and challenges as a result of the complexities of the internal environment of the Indochina Peninsula and the geopolitical competition of extraterritorial forces in the region.In this regard,China should make more efforts to improve relevant institutional arrangements for the Lancang-Mekong Cooperation,broaden the areas and enrich the content of cooperation,coordinate with extraterritorial forces and increase the number of stakeholders.
基金Sponsored by the National Natural Science Foundation of China (Grant No. 61101122 and 61071105)Fundamental Research Funds for the Central Universities (Grant No. HIT. NSRIF. 2010090)+1 种基金Science and Technology on Information Transmission and Dissemination in Communication Networks Laboratory (Grant No. ITD-U12004)Postdoctoral Science Research Development Foundation of Heilongjiang Province (Grant No. LBH-Q12080)
文摘Recently manifold learning algorithm for dimensionality reduction attracts more and more interests, and various linear and nonlinear,global and local algorithms are proposed. The key step of manifold learning algorithm is the neighboring region selection. However,so far for the references we know,few of which propose a generally accepted algorithm to well select the neighboring region. So in this paper,we propose an adaptive neighboring selection algorithm,which successfully applies the LLE and ISOMAP algorithms in the test. It is an algorithm that can find the optimal K nearest neighbors of the data points on the manifold. And the theoretical basis of the algorithm is the approximated curvature of the data point on the manifold. Based on Riemann Geometry,Jacob matrix is a proper mathematical concept to predict the approximated curvature. By verifying the proposed algorithm on embedding Swiss roll from R3 to R2 based on LLE and ISOMAP algorithm,the simulation results show that the proposed adaptive neighboring selection algorithm is feasible and able to find the optimal value of K,making the residual variance relatively small and better visualization of the results. By quantitative analysis,the embedding quality measured by residual variance is increased 45. 45% after using the proposed algorithm in LLE.
基金the initial result of the“Ethnic Situation of the Neighboring Countries Vs.the Ethnic Relation in China and China’s National Unity”,which is a sub-project of A Number of Important Basic Theoretical Research on Ethnic Issues under the Marxist Theory Research and Construction Project-2015
文摘In the international community,the internal ethnic issues of one country can easily spread out of its borders through the impact of internal and external factors to affect the national security of other countries,known as the spillover effect.Presently,the ethnic issues of China's neighboring countries that have real consequences on the country's national security break down mainly into four types:the internal ethnic conflict,the transnational ethnic issue,the issues related with immigrants and the collaboration of the Three Forces.The risk of spillover can be summed up according to the intensity of its effect in five categories:infiltration,springboard,spillover,immigration and harassment.As diverse ethnic issues of the neighboring countries have different effects on China's national security,the Chinese government must grasp the core element of each issue to formulate specific policies.
文摘Seismic pounding phenomena, particularly the collision of neighboring buildings under long-period ground motion, are becoming a significant issue in Japan. We focused on a specific apartment structure called the Nuevo Leon buildings in the Tlatelolco district of Mexico City, which consisted of three similar buildings built consecutively with narrow expansion joints between the buildings. Two out of the three buildings collapsed completely in the 1985 Mexican earthquake. Using a finite element code based on the adaptively shifted integration (ASI)-Gauss technique, a seismic pounding analysis is performed on a simulated model of the Nuevo Leon buildings to understand the impact and collapse behavior of structures built near each other. The numerical code used in the analysis provides a higher computational efficiency than the conventional code for this type of problem and enables us to address dynamic behavior with strong nonlinearities, including phenomena such as member fracture and elemental contact. Contact release and recontact algorithms are developed and implemented in the code to understand the complex behaviors of structural members during seismic pounding and the collapse sequence. According to the numerical results, the collision of the buildings may be a result of the difference of natural periods between the neighboring buildings. This difference was detected in similar buildings from the damages caused by previous earthquakes. By setting the natural period of the north building to be 25% longer than the other periods, the ground motion, which hada relatively long period of 2 s, first caused the collision between the north and the center buildings. This collision eventually led to the collapse of the centerbuilding, followed by the destruction of the north building.
基金This work was supported by National Nonprofit Institute Research Grants of CAF(CAFYBB2017QC003),NSFC(31370441,31670628)Guangdong Basic and Applied Basic Research Foundation(2020A1515010391).
文摘Plants respond differently to the identity of their neighbors,such as their sex and kinship,showing plasticity in their traits.However,how the functional traits of dioecious trees are shaped by the recognition of neighbors with different sex and kinship remains unknown.In this study,we set up an experiment with different kin/nonkin and inter/intrasexual combinations for a dioecious tree species,Diospyros morrisiana.The results showed that plants grew better with nonkin and intrasexual neighbors than with kin and intersexual neighbors.Kin combinations had significantly shorter root length in the resource-overlapping zone than nonkin combinations,suggesting that kin tended to reduce competition by adjusting their root distribution,especially among female siblings.Our study suggested that the seedling growth of D.morrisiana was affected by both the relatedness and sexual identity of neighboring plants.Further analysis by gas chromatography-mass spectrometry showed that the root exudate composition of female seedlings differed from that of male seedlings.Root exudates may play important roles in sex competition in dioecious plants.This study indicates that sex-specific competition and kin recognition interact and co-shape the traits of D.morrisiana seedlings,while intrasexual and nonkin neighbors facilitate the growth of seedlings.Our study implies that kin-and sex-related interactions depend on different mechanisms,kin selection,and niche partitioning,respectively.These results are critical for understanding how species coexist and how traits are shaped in nature.
基金NTT-DoCoMo Beijing Communication Labs the National High Technology Research and Development Program of China(No.2006AA01Z276).
文摘To overcome the problem of existing neighboring access point (AP) discovery methods in WLAN, for example they (PnP) of mul proposed. Us can not provide the accurate neighboring APs information needed for the Plug-and-Play ti-mode APs, three kinds of neighboring AP discovery and information exchange methods are ing these three neighboring AP discovery methods, passive discovery method, active discovery method and station assistant discovery method, the multi-mode AP can discover all neighboring APs and obtain needed information. We further propose two whole process flows, which combine three discovery methods in different manner, to achieve different goals. One process flow is to discover the neighboring AP as fast as possible, called fast discovery process flow. The other is to discover the neighboring AP with minimal interference to neighboring and accuracy of the method is confirmed APs, called the minimal interference process flow. The validity by the simulation.
文摘The binding energy and generalized stacking-fault energy (GSFE) are two critical interface properties of two dimensional layered materials, and it is still unclear how neighboring layers affect the interface energy of adjacent layers. Here, we investigate the effect of neighboring layers by comparing the differences of binding energy and GSFE between trilayer heterostructures (graphene/graphene/graphene, graphene/graphene/boron nitride,boron nitride/graphene/boron nitride) and bilayer heterostructures (graphene/graphene,graphene/boron nitride) using density functional theory. The binding energy of the adjacent layers changes from -2.3% to 22.55% due to the effect of neighboring layer, with a very small change of the interlayer distance. Neighboring layers also make a change from -2% to 10% change the GSFE, depending on the property of the interface between adjacent layers. In addition, a new simple expression is proven to describe the GSFE landscape of graphene-like structure with high accuracy.
文摘With the deepening of globalization,geographically speaking,East Asian countries have proceeded from their respective realist positions and tried to promote the successful practice of economic cooperation between countries after the Cold War into a discussion of new regionalism in East Asia and Asia-Pacificism.Although the prototype of the“East Asia Community”led by Association of Southeast Asian Nations(ASEAN)gradually emerged,the successful practice of the East Asia Summit proved that the low-binding regional integration model led by ASEAN has a high probability of becoming a classic sample of the“East Asia Community”.It not only maintains regional stability,promotes regional cooperation,shapes regional norms,but also builds a collective identity within the region.However,in today’s world,isolationism which takes the supremacy of national interests as the supremacy has risen.It is difficult to internalize the value identity into a super-national model that breaks through the principles of realism,breakthroughs in interests,and the power framework.The thorny issues pose various challenges to the nation-states in the region trying to integrate into regional integration.The openness of East Asian regionalism has led to the persistent illness of its generalization.In the context of insufficient political mutual trust among regional countries,intensified competition among major powers,and continued weakening of ASEAN leadership,it is often prone to controversy and doubt when proposing new cooperation initiatives or ideas.The idea of the“East Asia Community”that once guided East Asian cooperation and was temporarily ignored now is still the most realistic choice.Although the theoretical construction and practical roads of East Asian regionalism are full of thorns,difficulties coexist with opportunities.With the extensive participation of countries in the region,the optimization and reconstruction of the East Asian cooperation model will be worth looking forward to.