演變樹種 的英文怎麼說
中文拼音 [yǎnbiànshùzhǒng]
演變樹種
英文
succession species-
Niche breadth of four dominate populations at three age groups was studied by the methods of resource utilization ability and ratio. the result shows that : symplocos sectchuanensis is a typical gengeration species whi ch resource utilization ability is strong, and distribution is wide. meanwhile, go rdonia acuminata, castanopsis fargesis and pinus massoniana specialized at some d egree in resource utilizationm, their distribution is limited. especially, the ju venile of pinus massoniana specialized outstandingly. with the devlopment of pinu s massoniana, which is the pioneer population in mt. jinyun, the environment become s unfit to it ' s juvenile. it turns to needle and evergreen broad - leaves mixed fo r est. because the tolerance toward shading of gordonia acuminata is lower than tha t of castanopsis fargesis, gordonia acuminata will be substituted by castanopsis fargesis and other evergreen broad - leaves species are the edificators. the popul ation ' s ability of resource utilization is the inner factor of population distri bution and community succession. the distribution of light and the concentrate of nutrient ( such as n ) is the outer factors of community succession
對縉雲山森林植被的4個優勢種群3個年齡級生態位寬度進行了研究.結果表明,川灰木利用資源的能力最強、分佈廣,為典型的泛化種.大頭茶、栲樹、馬尾松對資源的利用在一定程度上特化,分佈上有一定的局限性.馬尾松的中齡組與幼齡組特化現象十分顯著.縉雲山森林植被的先鋒種馬尾松的發展,導致環境的改變不適于其幼齡個體的生長,群落演替到針闊葉混交林階段,最後發展為以栲樹等為建群種的常綠闊葉林.種群的資源利用能力,是種群分佈與群落演替的內在原因,光因子和營養元素(如n )是群落演替的主要外部動力Then, an improved genetic algorithm is proposed to solve this problem. this algorithm makes trees with the source and all destinations are the space of operation and filter operation. with hybrid selection operator, competition among brothers, greedy operation, filter operation
然後給出了一種基於遺傳演算法的實時多播路由選擇方法,並用改進的遺傳演算法進行了求解,該演算法採用包含源節點和目的節點的樹作為交叉和變異的空間的方法,通過加入混合選擇、小范圍競爭擇優的交叉變異操作,提高了全局搜索能力和收斂速度。Based on investigation of natural forest vegetation in chaoguanxigou watershed of rocky mountain area of north of china, the composition of species, structure of dbh of trees and species diversity of trees and shrubs in the course of forest succession are researched
摘要基於華北土石山區潮關西溝流域天然森林植被調查的基礎上,對森林植被群落演替中群落樹種組成、胸徑結構和生物多樣性變化進行了研究。The systematic and synthetic description and review of lianas, chiefly in tropic, are described and reviewed in this paper, in which some ecological questions of lianas are included distributed as follows : ( 1 ) the conception and significances of lianas ; ( 2 ) liana flora and its distribution in the world ; ( 3 ) its biological characteristics ; ( 4 ) its ecological characteristics ; ( 5 ) its abundance ( density ) and species - richness in tropical forest ; ( 6 ) the ecological significance of lianas - aggregation in gap and the variance of its abundance in the process of forest succession ; ( 7 ) the relationship between lianas and trees ; ( 8 ) the positive and the negative contribution of lianas to tropical forest ; ( 9 ) the types of climbing mechanism of lianas and its competitive predominance ; ( 10 ) global climate - variance ( co2 increase ) promotes abundance of lianas to increase, and some ecological consequence are resulted from which
摘要對藤本植物(以熱帶為主)研究的動態與發展進行了綜述,其中包括: ( 1 )藤本植物的概念及重要性; ( 2 )藤本植物區系和分佈; ( 3 )藤本植物的生物學特性; ( 4 )藤本植物的生態學特性; ( 5 )藤本在森林中的多度(密度)及種的豐富度; ( 6 )藤本在空地上聚生的生態意義以及它們在森林演進過程中的消長; ( 7 )藤本與樹木的相互關系; ( 8 )藤本對森林正面和負面的影響; ( 9 )藤本的攀援方式類別及其競爭優勢; ( 10 )全球氣候變化( co2濃度增高)促進藤本優勢度增長並導致不良的生態後果。A novel coding algorithm was presented for still ima ge using biorthogonal wavelet transform. combined with the visibility preaccentua tion before the quantization , a new data structure named extended q _ tree was pro posed to organize wavelet transformation coefficients. experimental results show that the new algorithm is very practical and with good performance
研究了一種基於雙正交小波變換的靜止圖象編碼演算法.結合帶視覺加權的標量量化技術,提出了一種新的數據結構? ?擴展四叉樹,從而實現了一種性能較好、復雜度較低的靜止圖象編碼方案Abstract : in this article an optimization method is applied to de sign open - type distribution networks. graph theory technology is used. its mathem at ical model considers both the investment of constructing lines and the cost of o peration. the main idea is getting the structure of tree network that meets with the technical constraint conditions and at the same time make the annual cost mi nimum. the examples of simulation show that this method is fast and effective
文摘:將圖論優化技術應用於配電網路的優化設計,提出了一種適合於開式配電網路規劃的優化方法.所建的數學模型綜合考慮了待建線路的投資和運行費用.求解方法是以圖論中的最短路徑問題為基礎,配合以開式網路潮流演算法,並通過可行路徑的合理變換,得出滿足技術約束條件且使年計算費用取極小值的樹狀網路結構My principal work is these : transforming image in wavelet at first, then encoding wavelet coefficients in sofm arithmetic methodology, lbg arithmetic methodology, dpcm encoding step by step, wavelet zero tree compression separately, reconstructing the image at last, so researching how to improve compression ratio, hi addition, the article puts forward a new arithmetic methodology, sl arithmetic methodology, on the base of comparing sofm arithmetic methodology with lbg arithmetic methodology what it needs emphasis is the variety of reconstructed image because of the diversity of mother wavelet
本人所做的工作主要圍繞著這樣的步驟:將圖像數據先進行小波變換,然後分別應用sofm演算法、 lbg演算法、 dpcm分步編碼、小波零樹壓縮等對圖像小波系數進行編碼,最後重構圖像。 akqnk44 wa從而研究如何能夠提高圖像壓縮比,並比較了各演算法在圖像壓縮中的特點。另外,根據sofm演算法、 lbg演算法在圖像壓縮中的各自特點,提出了一種新的算祛一七l演算法。The binary fat tree is a network topology which is prone to accomplish butterfly computing. according to this feature, a logical model for binary fat tree was constructed at first, and then a parallel fast fourier transform algorithm based on it was devel.
二叉胖樹網路結構是一種易於實現蝶式計算的網路拓撲結構,基於這一特點,首先構造了一種二叉胖樹的邏輯模型,並提出了一種基於該模型的并行快速傅立葉變換演算法。To the former one, since most previous work depends on the signature of nodes, which would be costly to be computed, a new way is proposed to discriminate those nodes that have the same paths in the intrinsic properties of the xml document. towards this end, the thesis introduces a series of notions related to the key path, which make the change detection of xml document easier. based on the notions, a change detection algorithm named kf - diff is presented, which is tailored to unordered trees
對於前者,針對已有演算法大多依賴非常耗時的結點簽名,並且演算法過程復雜的問題,本文提出了一種文檔變化檢測的處理方法,該方法利用文檔固有信息建立特徵參照體系,通過特徵路徑相關的一系列概念的引入,將傳統標號樹匹配問題轉化為無重復路徑的標號樹匹配問題,有效地解決了路徑等價類比較的問題,簡化了xml文檔的比較。( 3 ) combined with probability statistic knowledge, introduce the basic theory of message passing algorithm ; analyse the classical decoding algorithm of ldpc codes, including sum product algorithm which based on probability and llr, and min sum algorithm. ( 4 ) research message passing process on the tree ; according spa, turn the flooding schedule to serial schedule based on c - nodes and v - nodes, namely serial algorithm and, analyse de and complexity ; simulations show that the both serial algorithms could improve decoding performance, improve convergence property, reduce complexity
( 4 )研究了和積譯碼演算法在樹上的消息傳遞過程;在ldpc碼經典譯碼演算法基礎上,將洪水消息傳遞機制轉換成基於校驗節點的串列消息傳遞機制和基於變量節點的消息傳遞機制,分別對應串列譯碼演算法和串列譯碼演算法,並對密度進化和譯碼復雜度等方面進行分析;模擬結果表明,兩種串列譯碼演算法都使譯碼性能得到明顯提高,改善了消息收斂特性,降低了譯碼復雜度。The new image encoding algorithm based on analyzing the characteristics of the wavelet transform and the disadvantages of the ezw is presented
摘要在分析小波變換后系數特點和零樹編碼演算法的基礎上,提出了一種新的演算法。So far, there have been many heuristic algorithms for building decision trees. most are based on the entropy of information or vagueness, such as id3, min - ambiguity and their variation
目前,已有許多種構建決策樹的方法,大多數是基於信息熵的或信息的不確定性,例如, id3演算法, min ? ambiguity演算法以及它們的變異版本。This paper analysis three kinds of deformations and propose resolving method respectively. a bottom - up updating method is propose especially which can compute the bounding volume of parent node through bounding volumes of the two children by k comparison. furthermore, a traverse tracing strategy that can speed up collision detection is proposed in this paper based on developing and utilizing temporal - spatial coherence in virtual environment
本文在對幾種變形情況進行分析的基礎上,分別提出了相應的解決方法,並著重提出了一種自底向上的包圍盒樹快速更新演算法,通過k次比較運算由子結點的包圍盒得到父結點的包圍盒,以解決拉壓變形和拓撲變化后包圍盒樹的更新問題。分享友人