Diversity of filamentous fungi in leaf litter and aerial litter in semi-deciduous forest,Bahia, Brazil

The fungi have wide distribution in ecosystems and can be found colonizing various substrates,where they act as efficient decomposers,participating in cycling of nutrients.The present study aimed to assess the diversity,richness and composition of filamentous fungi in leaf litter and aerial litter in a semi-deciduous forest in the Chapada Diamantina,Bahia,Brazil.Samples of leaf litter and aerial litter were collected monthly from October/2009 to September/2010 in eight installments in the studied area.Those samples were washed,placed in moist chambers and incubated.47 taxa were identified,37 in leaf litter and 35 in aerial litter,with 25 species common to both.A similarity of 69 % according to Sorensen index.The similarity was considered low when the sample points were compared to the same litter.Most fungi showed sporadic intervals.     

干旱区内陆艾比湖流域景观格局时空变化及生态安全评价

[目的]为了探讨艾比湖流域近10a间景观格局及生态安全的动态变化。[方法]运用RS和GIS技术,并结合景观指数和生态弹性度对该流域生态安全进行了综合评价。[结果](1)近10a来,艾比湖流域土地利用变化剧烈,说明景观格局持续受社会经济发展两方面矛盾的巨大压力;(2)2001年斑块个数为2 560个,而2009年增加至3 476个,说明该流域生态环境整体呈破碎化趋势。景观破碎度由2001年的0.054 0增加为2009年的0.073 3,说明其景观趋于不稳定,生态安全性降低;(3)2001—2009年生态弹性度呈"∧"型变化趋势,先由2001年的1.20×107增加为2005年的1.57×107,然后再降为2009年的1.49×107,但总体是趋于增大的趋势。[结论]从整体上综合考虑,2001—2009年艾比湖流域土地利用的景观生态安全度降低。     

光怪陆离的布达佩斯动物园建筑群

在布达佩斯，如果说市民们仅仅是为了观赏动物而造访动物园，那动物园恐怕早就关门大吉了．至少门庭罗雀。尽管布达佩斯动物园一只也没有像熊猫、虎鱼这样的珍稀动物来吸引游客的眼球，但生意的持久火爆却匪人所思。动物园共饲养有3000只动物，占地面积为104b顷。它作为世界上著名动物园之一而享誉全球。而动物的生存环境之极其狭窄，也在世界上列属前一、二位。     

温度对柴油和二甲醚喷射系统性能的影响

针对普通油泵-油管-油嘴燃油系统,建立了喷射系统的数学模型.对不同温度下柴油和二甲醚喷射系统性能进行了数值模拟.研究表明:在相同温度下,二甲醚喷嘴压力的上升和下降速率、压力峰值都比柴油低,20℃时二甲醚较柴油下降51.1%,50℃时较柴油下降45.2%,喷射速度和累积喷油量均远低于柴油,针阀开启时刻较柴油明显延后;在最大速度点,20℃和50℃时二甲醚分别较柴油下降38.8%和36.8%.随着温度的升高,柴油和二甲醚的喷嘴压力、喷射速度下降,针阀开启时刻延迟,且柴油的索特平均直径明显减小.     

内蒙古白绒山羊优质高产新品系绒毛物理性能的研究

通过对内蒙古3个盟市的4个育种基地绒样测试结果表明,内蒙古白绒山羊优质高产新品系羊绒细长、色白、光泽和手感良好,已达到国际领先水平,是优质的纺织原料.绒毛细度、长度、密度、强伸度、净绒率、含脂率符合绒山羊品种指标的要求.绒毛细度、绒层高度和净绒率已达到了攻关指标的要求.     

Corner Point Detection Based on Adaptive Line Approximation

The detection of corner points is one of the basic problems of computer vision. Usually the key question of detecting corner points is how to calculate curvature. This paper presents a novel approach of calculating the backward and forward direction of reference point based on the adaptive line approximation. Our line approximation method objects minimize the distance error and the length of approximation widow adaptively changes with the approximation error. Our adaptive method finds a compromise between the length of approximation widow and the calculation precise. The experiments results show, the method can robustly, effectively and precisely locate corner point for curves with apparent corners with little computation.     

And/or Dag Method in Dynamic Design and Maintenance of Data Warehouse

A data warehouse (DW) is taken as a set of materialized views defined over base relations. It is dynamic entity that evolves continually over time .As time passes, new queries can be made into new views to be added to the DW. Data Warehouse is expressed as and/or dag can describe the relations between queries in DW preferably. Thus, the design of DW can simulate the problem of state space search, relevant exchange rule may define state exchange rule. It can achieve the dynamic design of DW by exchanging and predigesting of state space search. A dynamic design way is proposed to add the new views to the DW by an example.     

Design of Manufacturing System for Business

In the new environment, product development is the core of product innovation and quickly responsive to the market for the enterprises. The speed and effectiveness of development is the key factor to the success of product development. The design for business is the key technique in achieving the effectiveness of product development. And manufacturing system is the bridge between business and products. The design method of facing business is discussed, and the design flow and content of manufacturing system supporting facing business are pointed out. At the same time, the author also sets forth the construction definition, the construction design and the detailed design of the manufacturing system. So the design flow of manufacturing system facing business is established.     

Walsh Sequences Generation with Rademacher Functions and Its Digital Realization

This paper first discusses the application of Walsh sequences in the forward link and the reverse link of the IS-95 system. The advantages and disadvantages of each way generating Walsh sequences are analyzed. The theory and step of using Rademacher function to construct Walsh sequences is discussed especially. Then a way of generating Walsh sequences with CPLD is presented and the Design is described by VHDL on CPLD chip. This way mostly relays on digital logic operation, so it can be realized easily through digital circuit and it needs little memory unit. The result of emluator makes clear this way is feasible.     

封育对沙化典型草原土壤种子库的影响

本文对封育和未封育放牧草地土壤种子库种子密度、种子库组成、种子库物种多样性及均匀性进行了比较研究,并得出的主要结论是:①实施封育提高了土壤种子库种子密度。②封育能使草地中的优良禾草及多年生植物种子所占比例增加。③封育能使土壤种子库物种多样性及丰富度增加。