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1.
The rise of granular computing   总被引:3,自引:0,他引:3  
This paper has two purposes. One is to present a critical examination of the rise of granular computing and the other is to suggest a triarchic theory of granular computing. By examining the reasons, justifications, and motivations for the rise of granular computing, we may be able to fully appreciate its scope, goal and potential values. The results enable us to formulate a triarchic theory in the light of research results from many disciplines. The three components of the theory are labeled as the philosophy, the methodology, and the computation. The integration of the three offers a unified view of granular computing as a way of structured thinking, a method of structured problem solving, and a paradigm of structured information processing, focusing on hierarchical granular structures. The triarchic theory is an important effort in synthesizing the various theories and models of granular computing.  相似文献   

2.
Sky islands are high-elevation areas in continental mountain ranges,which are geographically isolated.We adopted this concept for the mountains in southwest China,which are among the most important biodiversity hot spots on earth.We reviewed the phylogeographic studies of this area and highlighted the sky-island features.We concluded that the genetic structures of species in these islands were shaped by complex topography,climate and habitats.The global climate change,such as Pleistocene climate fluctuations and periodic uplift of the Qinghai–Tibetan Plateau,also have important effects on biodiversity and geographic patterns,when species have responded idiosyncratically by changing their distributions or through adaptation.Future research needs in sky islands include multilocus data and comparative phylogeographic studies,integrating with the methodological advances in the other fields.Using these approaches,we can examine to what degree the geographic,climate and/or biological factors,shape strong geographic patterns,promote diversification/speciation and preserve species/genetic diversity.We hope this paper will inspire future work to uncover the mechanism that has generated the endemic biodiversity and to further resolve the most essential problem:How to protect the biodiversity with limited funding during the coming drastic global climate change.  相似文献   

3.
The rapid expansion of the Internet has resulted not only in the ever growing amount of data therein stored, but also in the burgeoning complexity of the concepts and phenomena pertaining to those data. This issue has been vividly compared by the renowned statistician, prof. Friedman of Stanford University, to the advances in human mobility from the period of walking afoot to the era of jet travel. These essential changes in data have brought new challenges to the development of new data mining methods, especially that the treatment of these data increasingly involves complex processes that elude classic modeling paradigms. “Hot” datasets like biomedical, financial or net user behavior data are just a few examples. Mining such temporal or stream data is on the agenda of many research centers and companies worldwide. In the data mining community, there is a rapidly growing interest in developing methods for process mining, e.g〖DK〗., for discovery of structures of temporal processes from data. Works on process mining have recently been undertaken by many renowned centers worldwide. This research is also related to functional data analysis , cognitive networks , and dynamical system modeling, e.g., in biology. In the lecture, we outline an approach to discovery of processes from data and domain knowledge which is based on the roughgranular computing.  相似文献   

4.
In this article, a real number is defined as a granulation and the real space is transformed into real granu-lar space[1]. In the entironment, solution of nonlinear equation is denoted by granulation in real granular space. Hence,the research of whole optimization to solve nonlinear equation based on granular computing is proposed[2]. In classicalcase, we solve usually accurate solution of problems. If can't get accurate solution, also finding out an approximate solutionto close to accurate solution. But in real space, approximate solution to close to accurate solution is very vague concept. Inreal granular space, all of the approximate solutions to close to accurate solution are constructed a set, it is a granulation inreal granular space. Hence, this granulation is an accurate solution to solve problem in some sense, such, we avoid to sayvaguely "approximate solution to close to accurate solution". We introduce the concept of granulation in one dimension real space. Any positive real number a together with movinginfinite small distance ε will be constructed an interval [a-ε,a ε], we call it as granulation in real granular space, denotedby ε(a) or [a]. We will discuss related properties and operations[3] of the granulations. Let one dimension real space be R, where each real number a will be generated a granulation, hence we get a granularspace R* based on real space R. Obviously, R∈R*. Infinite small number in real space R is only O, and there are three in-finite small granulations in real number granular space R* : [0], [ε] and [-ε]. As the graph in Fig. 1 shows. In Fig. 1,[-ε] is a negative infinite small granulation,[ε] is a positive infinite small granulation,[0] is a infinite small granulation.[a] is a granulation of real number a generating, it could be denoted by interval [a-ε,a ε] in real space [3-5].Letf(x)=0 be a nonliner equation,its graph in interval[-3,10]id showed in Fig.2.Where -3≤x≤10 Relation ρ(f‖,ε)is defied is follows:(x1,x2)∈ p(f‖,ε)iff |f(x1)- f(x2)|<εWhere ε is any given small real number.We have five appoximate solution sets on the nonliner equation f(x)=0 by ρ(f‖,ε)∧|f(x)|[a,b]max,to denote by granulations[xi1 xi2/2],[xi3 xi4/2],[xi5 xi6/2],[xi7 xi8/2]and[xi9 xi10/2]respectively,where |f(x)|[a,b]max denotes local maximum on x ∈[a,b].This is whole optimum on nonliear equation in interval [-3,10].We will get best opmension solution on nonliner equation via computing f(x)to use the five solutions dented by grandlation in one dimension real granlar space[2,5].  相似文献   

5.
This paper investigates a novel molecular scale material removal mechanism in chemical mechanical polishing (CMP) by incorporating the order-of-magnitude calculations, particle adhesion force, defect of wafer, thickness of newly formed oxidized layer, and large deformation of pad/particle not discussed by previous analysis. The theoretical analysis and experimental data show that the indentation depth, scratching depth and polishing surface roughness are on the order of molecular scale or less. Therefore, this novel mechanism has gained the support from wide order-of- magnitude calculations and experimental data. In addition, with the decrease in the particle size, the molecular scale removal mechanism is plausibly one of the most promising removal mechanisms to clarify the CMP polishing process. The results are useful to substantiating the molecular-scale mechanism of the CMP material removal in addition to its underlying theoretical foundation.  相似文献   

6.
Surface seawater was collected for ~(226)Ra measurement in the North Pacific Subtropical Gyre from July to October, 1999 and October to December, 2003. Combined with the historical data reported for this sea area, a declined trend of surface ~(226)Ra concentrations was observed since 1960s, indicating the ecosystem shift in response to global warming. On one side, the enhanced stratification of the upper water column resulting from global warming reduced the ~(226)Ra input from the depth, on the other, the temporal increase of biological production resulting from the climate-related ecosystem structure change strengthened the ~(226)Ra removal from the surface ocean. Both the physical and biological processes resulted in the decrease of surface ~(226)Ra concentrations in the North Pacific Subtropical Gyre. The temporal trend of surface ~(226)Ra concentrations was consistent with the trends of chlorophyll a, silicate, phosphate and primary production previously reported. This study provided ~(226)Ra evidence for the ecosystem shift under global change.  相似文献   

7.
Distributed denial of service (DDoS) attacks exploit the availability of Web servers, resulting in the severe loss of their connectivity. We present a robust IP packets filtering mechanism which combines the detection and filtering engine together to protect Web Servers from DDoS Attacks. The mechanism can detect DDoS attacks by inspecting inbound packets with an IP address database, and filter out lower priority IP addresses to preserve the connection for valid users by monitoring the queues status. We use the Netfilter's technique, a framework inside the Linux 2.4. X, to implement it on a Web server. Also, we evaluate this mechanism and analyze the influence of some important parameters on system performance. The experimental results show that this mechanism is effective against DDoS attacks.  相似文献   

8.
We present a secure storage system named Hermit FS against many types of attacks. HermitFS uses strong cryptography algorithms and a secure protocol to secure the data from the time it is written to the time an authorized user accesses it. Our experimental results and secure analysis show that HermitFS can protect information from unauthorized access in any open environment with little penalty of data overhead and acceptable performance.  相似文献   

9.
Orogenesis of the Qinghai-Tibetan Plateau,which occurred in a stepwise manner,contributed to the extreme aridity of the Tarim Basin,resulting in vulnerable and unstable ecosystems.Quaternary climatic oscillations may have affected the ecosystems and,consequently,the distributions and genetic structuring of the Tarim Basin’s biota.We used nucleotide sequence data from 2 mitochondrial (mt) DNA genes (Cyt b and the D-loop) to test hypotheses associated with the matrilineal and demographical histories of the Tarim Basin’s endemic Yarkand hare (Lepus yarkandensis).Range-wide sampling involving 20 populations and 224 individuals detected 126 haplotypes that clustered into 5 major lineages in both the phylogenetic tree and median-joining network.Populations from the northern and eastern Tarim Basin shared a similar history,as did those from the western and southern regions.Demographical analysis and genetic diversity estimations suggested that the western and southern regions might have served as glacial refugia for the Yarkand hare during Quaternary climatic oscillations.The distribution of the Yarkand hare,especially in the northern and eastern parts,probably represented 3 postglacial colonization events,dated to 0.21,0.090 and 0.054 MYA,which corresponded to known interglacial periods.Given the relatively complete geographic isolation between the eastern and southern populations,the Yarkand hare likely dispersed during postglacial periods from the southwest to the north,and then onward to the east.The absence of water likely forced the species into refugia,and this differed from other Pleistocene biogeographical drivers.The demographical and historical patterns have important implications for conservation.  相似文献   

10.
Thrust-nappe structures and extensional structures simultaneonsly occur in the northern part of the Dabie Mountains. The systematic structural study reveals that extensional structures along the Mozitan-Xiaotian fault and thrust-nappe structures that take the Jinzhai-Shucheng fault as their frontal thrust share the same shear sense, and display a transitional relationship from the ductile extensional structure of deep level in the south to the ductile-brittle and brittle thrust-nappe structure of shallow level in the north. The extensional and thrnst-nappe structures in the region are explained to result from post-collisional processes by the continuous subduction of the Yangtze continental block and the extension induced by the uplifting of the core part of the Dabie Mountains, which are components of the exteasional structures produced in the exhumation process of the ultrahigh pressure metamorphic rocks in the Dabie Mountains. Because of the frontal blocking in the process of the north-westward spreading, the extension and detachment of the low-grade metamorphic rocks along the Mozitan-Xiaotian fault was transformed into the northwestward thrustiag, resulting in the thrust-nappe structures. They developed in the period of 200-170 Ma, maybe last till the late Jurassic.  相似文献   

11.
 采用升流式厌氧污泥床(UASB)反应器,以城市污水处理厂二沉池活性污泥为种泥,研究好氧絮状污泥的厌氧颗粒化过程及其机制.UASB在污泥负荷(SLR)0.25kg(COD)/(kg(VSS)·d)和水力负荷(HLR)0.1m3/(m2·h)的条件下启动后,通过分阶段缩短水力停留时间(HRT)的方式逐步将SLR和HLR提高到0.52kg(COD)/(kg(VSS)·d)和0.3m3/m2·h,经过150d的连续运行,成功培育出了厌氧颗粒污泥,系统对COD的去除率达到了95%以上.厌氧颗粒污泥的形成过程先后经历了污泥驯化期、微生物聚集体形成期、初生颗粒污泥形成期、次生颗粒污泥形成期、成熟颗粒污泥形成期5个时期.好氧絮状污泥的厌氧颗粒化机制整体上符合二次核学说,其中初生颗粒污泥的形成符合黏液学说,而次生颗粒污泥的形成机制与目前已报道的厌氧颗粒污泥形成机制不同,其内核是由初生颗粒污泥破碎后的碎片组成,产甲烷丝状菌和其他细菌通过插入碎片中或者附着于碎片表面的方式形成聚集体,并逐渐发展成为次生颗粒污泥.  相似文献   

12.
生物絮凝剂对好氧污泥颗粒化性能及其种群结构的影响   总被引:1,自引:0,他引:1  
为了加速好氧污泥的颗粒化进程,在好氧颗粒污泥培养的过程中投加生物絮凝剂,研究其对颗粒污泥理化性能的影响。利用分子生物学手段分析颗粒污泥的种群结构,探讨生物絮凝剂促进污泥颗粒化的作用机理。结果表明,生物絮凝剂的投加使污泥颗粒化的时间由56 d缩短为28 d,形成的颗粒具有良好的疏水性能和沉降性能。DGGE分析显示颗粒污泥的群落多样性十分丰富,总共测序的28个OTUs中,存在较多的是Actinobacteria和Proteobacteria的α和γ亚群,大约占OTUs总数的64.3%。而且投加的能分泌胞外多糖黏液的菌种Devosia hwasunensis strain HST2-16T、Tetrasphaera elongate在颗粒形成和维持其稳定性方面起到了重要的作用。  相似文献   

13.
知识过滤和它的依赖推理发现   总被引:8,自引:0,他引:8  
知识具有颗粒,知识具有粒度;颗粒,粒度是知识的两个基本特征;知识的颗粒特征,知识的粒度特征与知识的属性保持着紧密联系,属性的变化引起知识颗粒特征,知识粒度特征的变化.本文将物理学中物质具有颗粒的概念和过渡的概念引入到粗集(rough set)理论与应用的研究中,提出了知识过滤的概念,给出知识过滤的数值度量,知识筛子原理.利用知识过滤的概念,给出知识过滤在依赖推理中的推理结构,依赖推理的数值关系和在知识发现中的应用.知识过滤与依赖推理相互交叉,互补共享,是知识发现研究的一个新方向.  相似文献   

14.
UASB反应器中高效能厌氧产酸污泥颗粒化的研究   总被引:2,自引:0,他引:2  
杨虹 《上海交通大学学报》1995,29(5):165-169,186
在产酸UASB反应器中,以配制葡萄糖废水为基质能够快速培养得到高活性、高沉降性的厌氧产酸颗粒污泥,形成高效能的产酸颗粒污泥床,反应器体积有机负荷达210gCOD/L·d时,酸化率为93%;观察研究了产酸污泥颗粒化过程中生物相和气体成分的变化规律,得出了产酸污泥颗粒化的主要控制条件是在反应器启动初期控制反应器内的PH为4.0左右;最后,探讨并提出了产酸污泥颗粒化机理.  相似文献   

15.
粒计算作为研究热点之一, 使得用多角度、多层次的方法研究问题变为可能。将粒计算引入决策形式背景, 将会获得更为精确的决策规则。从属性粒度树的角度出发, 首先定义了多粒度决策形式背景,其次研究了粒化前后协调性之间的关系,最后给出了粒化前后多粒度决策形式背景上的规则之间的关系。  相似文献   

16.
接种污泥对好氧污泥颗粒化影响的实验研究   总被引:1,自引:0,他引:1  
为了加快污泥颗粒化进程,在气升式内循环序批反应器中,取普通絮状活性污泥和在絮状污泥中添加一定比例的好氧颗粒污泥分别为接种污泥,进行好氧颗粒污泥的培养,探讨其对污泥颗粒化速度及生物降解性能的影响。结果表明,接种污泥中适量添加颗粒污泥能使颗粒成熟时间由35 d缩短为28 d,缩短了反应器启动时间,培养的成熟颗粒污泥具有较好的沉降性能和降解性能,SVI稳定在36 mL/g左右,沉降速度达36.23 m/h,COD、氨氮和总磷的去除率分别达到97.86%、90.23%、89.60%。  相似文献   

17.
利用粒计算对机器学习中的ID3算法给予重新思考与实现,采取人类问题求解的结构化思维方式,对数据进行粒化表示,使得机器问题求解的思路更易于让人接受,且运算模式更适于计算机上的实现.  相似文献   

18.
为了探究颗粒污泥对燃煤厂烟气脱硫废水营养型污染物的去除及微生物种群结构的变化特征,建立序批式厌氧/好氧反应器,以预处理后的燃煤厂烟气脱硫废水为研究对象,分析了污泥颗粒化进程中污泥特征,营养型污染去除及微生物群落结构的演变规律。结果表明污泥颗粒化进程中污泥沉降指数(SVI)显著下降,污泥中生物量显著升高,在120 d时,SVI下降至62 mL/g,混合液总悬浮固体(MLTSS)升高至7.1 g/L。此外颗粒污泥胞外聚合物中蛋白质(PN)显著提高,PN/多糖(PS)升高至2.71-2.74。在稳定运行期,颗粒污泥对COD,NH4+-N及总磷(TP)去除效率分别高达89.25-89.56%,93.4%和73.2%。微生物群落结构演变揭示污泥颗粒化进程提高Comamonadaceae及Pseudomonadaceae的相对丰度,从而提高脱氮除磷效率。  相似文献   

19.
设计了一种针对时间序列的k平面聚类算法,在时间维度和数值维度上同时对所有时序数据点进行聚类,从而将所有数据点划分到若干个不等长的时间窗口.在每个时间窗口上建立线性模糊信息粒子,最终得到原始时间序列的分段线性粒化表示.为便于采用模糊推理系统进行时间序列的预测,还定义了这些线性粒子的距离,从而构建了一种基于线性模糊信息粒子的预测方法.实验表明,所提出的预测方法可以有效地对具有伪周期的时间序列进行长期预测.   相似文献   

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