• 제목/요약/키워드: Yunnan

검색결과 345건 처리시간 0.024초

ALMOST PERIODIC SOLUTION FOR A n-SPECIES COMPETITION MODEL WITH FEEDBACK CONTROLS ON TIME SCALES

  • Li, Yongkun;Han, Xiaofang
    • Journal of applied mathematics & informatics
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    • 제31권1_2호
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    • pp.247-262
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    • 2013
  • In this paper, using the time scale calculus theory, we first discuss the permanence of a $n$-species competition system with feedback control on time scales. Based on the permanence result, by the Lyapunov functional method, we establish sufficient conditions for the existence and uniformly asymptotical stability of almost periodic solutions of the considered model. The results of this paper is completely new. An example is employed to show the feasibility of our main result.

GLOBAL EXPONENTIAL STABILITY OF ALMOST PERIODIC SOLUTIONS OF HIGH-ORDER HOPFIELD NEURAL NETWORKS WITH DISTRIBUTED DELAYS OF NEUTRAL TYPE

  • Zhao, Lili;Li, Yongkun
    • Journal of applied mathematics & informatics
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    • 제31권3_4호
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    • pp.577-594
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    • 2013
  • In this paper, we study the global stability and the existence of almost periodic solution of high-order Hopfield neural networks with distributed delays of neutral type. Some sufficient conditions are obtained for the existence, uniqueness and global exponential stability of almost periodic solution by employing fixed point theorem and differential inequality techniques. An example is given to show the effectiveness of the proposed method and results.

AN ANALYSIS ON THE RARE SUBTYPES OF THE FAST SOLAR RADIO ACTIVITY

  • XIE R. X.;WANG M.
    • 천문학회지
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    • 제29권spc1호
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    • pp.331-332
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    • 1996
  • We present 3 rare subtypes of the FFSs observed with high temporal resolution at 4-frequency (1.42, 2.13, 2.84 and 4.2G GHz). The various FFSs occurred during the main and post-flare phase can demonstrate that coronal nonthermal electron acceleration/injection may go through the whole development process of flares, and deduce that there may exist the re-forming of loop-like structures in the post-flare phase, and the complex multi-type magnetic structures in corona.

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Two Species of Bryoria (Lichenized Ascomycota, Parmeliaceae) from the Sino-Himalayas

  • Wang, Li-Song;Harada, Hiroshi;Koh, Young-Jin;Hur, Jae-Seoun
    • Mycobiology
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    • 제33권4호
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    • pp.173-177
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    • 2005
  • We performed a taxonomic study on two species of the genus Bryoria from the Sino-Himalayas, SW-China. B, nadvornikiana is new to China and B. furcellata is new to Yunnan and Sichuan provinces in the Sino-Himalayas. Morphology, habitat, distributions and chemistry of the two species are discussed.

Research on Metadata Model of Data Warehouse

  • Zeng, Zhi-Yong;Yu, Jian-Kun
    • 한국산업정보학회:학술대회논문집
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    • 한국산업정보학회 2007년도 춘계학술대회
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    • pp.72-79
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    • 2007
  • OMG's Common Warehouse Metamodel is now a single data warehouse metadata standard. Interchange of metadata between data warehousing tools and metadata repositories made easy and convenient by using CWM. In this paper, we present the origin, importance and architecture of CWM, and offer an application case.

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SINGULARITY FORMATION FOR A NONLINEAR VARIATIONAL SINE-GORDON EQUATION IN A MULTIDIMENSIONAL SPACE

  • Fengmei Qin;Kyungwoo Song;Qin Wang
    • 대한수학회보
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    • 제60권6호
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    • pp.1697-1704
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    • 2023
  • We study a multidimensional nonlinear variational sine-Gordon equation, which can be used to describe long waves on a dipole chain in the continuum limit. By using the method of characteristics, we show that a solution of a nonlinear variational sine-Gordon equation with certain initial data in a multidimensional space has a singularity in finite time.

Phylogenetic Diversity of Bacteria in an Earth-Cave in Guizhou Province, Southwest of China

  • Zhou, Jun-Pei;Gu, Ying-Qi;Zou, Chang-Song;Mo, Ming-He
    • Journal of Microbiology
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    • 제45권2호
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    • pp.105-112
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    • 2007
  • The objective of this study was to analyze the phylogenetic composition of bacterial community in the soil of an earth-cave (Niu Cave) using a culture-independent molecular approach. 16S rRNA genes were amplified directly from soil DNA with universally conserved and Bacteria-specific rRNA gene primers and cloned. The clone library was screened by restriction fragment length polymorphism (RFLP), and representative rRNA gene sequences were determined. A total of 115 bacterial sequence types were found in 190 analyzed clones. Phylogenetic sequence analyses revealed novel 16S rRNA gene sequence types and a high diversity of putative bacterial community. Members of these bacteria included Proteobacteria (42.6%), Acidobacteria (18.6%), Planctomycetes (9.0 %), Chloroflexi (Green nonsulfur bacteria, 7.5%), Bacteroidetes (2.1%), Gemmatimonadetes (2.7%), Nitrospirae (8.0%), Actinobacteria (High G+C Gram-positive bacteria, 6.4%) and candidate divisions (including the OP3, GN08, and SBR1093, 3.2%). Thirty-five clones were affiliated with bacteria that were related to nitrogen, sulfur, iron or manganese cycles. The comparison of the present data with the data obtained previously from caves based on 16S rRNA gene analysis revealed similarities in the bacterial community components, especially in the high abundance of Proteobacteria and Acidobacteria. Furthermore, this study provided the novel evidence for presence of Gemmatimonadetes, Nitrosomonadales, Oceanospirillales, and Rubrobacterales in a karstic hypogean environment.

중국 윈남성 소수민족 복식의 장신구 특성 - 바이족(白族), 좡족(壮族), 다이족(傣族), 장족(藏族), 하니족(哈尼族)을 중심으로 - (Characteristics of fashion accessories of minorities in Yunnan, China - focused on Bai, Zhuang, Hani, Dai, and the Zang nationality -)

  • 조선맹;윤정아;이연희
    • 한국의상디자인학회지
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    • 제20권1호
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    • pp.109-124
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    • 2018
  • This study focused on the accessory of clothes of minority groups in Yunnan province to further the research about specific accessories' development in the future. Among the minorities in Yunnan, this study centralized characteristics of ornaments, hats and belts among five minority groups such as the Bai, Zhuang, Hani, Dai, and the Zang as representatives to study in detail because these five ethnicities have a relatively long history and plentiful information. The results are as follows: First, exaggeration means large gorgeous patterns that attract attention. Generally, there are many natural resources that can be used in places where these minority groups live such as gems, gold, silver shells and animals' horns, bone, teeth and the like. Headdress includes combs, loops, hairpins and other similar articles. Second, nature is a very fundamental part that people rely on for existence and development. The production and living that people need in life all depend on nature. The design of accessories is made from animal forms and patterns of clothes are presented through embroidery and wax printing. Designers always tried to add natural elements to their works. Third, symbolism consists of two aspects: One is the people's imagination, which related to actual materials, and the other is the product of imagination that provides better conditions to inspire people when they design. In China, most minority groups believe in Buddhism. The symbols in the clothing show their devout faith. Even the method of wear has many special implications like the use of accessories and length of clothing. The pattern of dragons and use of golden, red and other colors all have a proper symbolic significance in modern designs.

OBSERVATIONS OF EUV RECURRING JETS IN AN ACTIVE REGION CONFINED BY CORONAL LOOPS

  • Zheng, Yan-Fang;Wang, Feng;Ji, Kai Fan;Deng, Hui
    • 천문학회지
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    • 제46권5호
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    • pp.183-190
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    • 2013
  • Recurring jets, which are jets ejected from the same site, are a peculiar type among various solar jet phenomena. We report such recurring jets ejecting from the same site above an active region on January 22, 2012 with high-resolution multi-wavelength observations from Solar Dynamics Observatory(SDO). We found that the recurring jets had velocities, lengths and lifetimes, but had similar directions. The visible brightening appeared at the jet base before each jet erupted. All the plasma produced by the recurring jets could not overcome the large coronal loops. It seemed that the plasma ejecting from the jet base was confined and guided by preexisting coronal loops, but their directions were not along the paths of the loops. Two of the jets formed crossing structures with the same preexisting filament. We also examined the photospheric magnetic field at the jet base, and observed a visible flux emergence, convergence and cancellation. The four recurring jets all were associated with the impulsive cancellation between two opposite polarities occurring at the jet base during each eruption. In addition, we suggest that the fluxes, flowing out of the active region, might supply the energy for the recurring jets by examining the SDO/Helioseismic and Magnetic Imager (HMI) successive images. The observational results support the magnetic reconnection model of jets.

Treatment of natural rubber wastewater by membrane technologies for water reuse

  • Jiang, Shi-Kuan;Zhang, Gui-Mei;Yan, Li;Wu, Ying
    • Membrane and Water Treatment
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    • 제9권1호
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    • pp.17-21
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    • 2018
  • A series of laboratory scale experiments were performed to investigate the feasibility of membrane separation technology for natural rubber (NR) wastewater treatment and reuse. Three types of spiral wound membranes were employed in the cross-flow experiments. The NR wastewater pretreated by sand filtration and cartridge filtration was forced to pass through the ultrafiltration (UF), nanofiltration (NF) and reverse osmosis (RO) membranes successively. The UF retentate, which containing abundant proteins, can be used to produce fertilizer, while the NF retentate is rich in quebrachitol and can be used to extract quebrachitol. The permeate produced by the RO module was reused in the NR processing. Furthermore, about 0.1wt% quebrachitol was extracted from the NR wastewater. Besides, the effluent quality treated by the membrane processes was much better than that of the biological treatment. Especially for total dissolved solids (TDS) and total phosphorus (T-P), the removal efficiency improved 53.11% and 49.83% respectively. In addition, the removal efficiencies of biological oxygen demand (BOD) and chemical oxygen demand (COD) exceeded 99%. The total nitrogen (T-N) and ammonia nitrogen (NH4-N) had approximately similar removal efficiency (93%). It was also found that there was a significant decrease in the T-P concentration in the effluent, the T-P was reduced from 200 mg/L to 0.34 mg/L. Generally, it was considered to be a challenging problem to solve for the biological processes. In brief, highly resource utilization and zero discharge was obtained by membrane separation system in the NR wastewater treatment.