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THE STUDY OF A SPECIOUS INVASIVE PLANT,WATER HYACINTH ( EICHHORNIA CRASSIPES):ACHIEVEMENTS AND CHALLENGES
入侵植物凤眼莲研究现状及存在的问题

GAO Lei,LI Bo,<br>高,
植物生态学报 , 2004,
Abstract: 凤眼莲(Eichhornia crassipes)原产南美洲,被列为世界十大恶性杂草之一,现已入侵了非洲、亚洲、北美洲、大洋州、甚至欧洲等5个大洲,至少62个国家和地区都受到了凤眼莲入侵的危害.凤眼莲的入侵已经引起了一系列的生态、经济、社会问题:首先,它改变了当地水体生态系统的物理、化学环境,进而影响水体生态系统的生物多样性,破坏食物链、物质循环等生态过程的正常运行;其次,凤眼莲造成当地经济的重大损失,航运、渔业、水利等都受到了危害;再次,凤眼莲的入侵爆发也对当地居民饮水、健康等造成威胁.目前,对于凤眼莲的控制及其治理主要有物理的、化学的、以及生物的等3种方法.利用天敌、病菌、以及化感作用等的生物控制被许多专家和学者推崇,同时,利用生物控制凤眼莲入侵也日益成为研究的热点.但是,综合目前对于凤眼莲的认识和研究,仍然具有片面性,需要从生物特性、种群生态、生态系统等方面深入研究凤眼莲入侵机制.而利用生物控制凤眼莲的研究和技术尚不完善,需要进行种间竞争、捕食及遗传变异等方面的探讨和研究.通过总结控制凤眼莲各种方法的长处和不足,最后指出利用生物的方法,并结合污水治理、水系宏观调控及监测等方法,综合治理凤眼莲,是十分必要的,而且也是最具有前景的.
Two-dimensional Extension of Minimum Error Threshold Segmentation Method for Gray-level Images
灰度图像最小误差阈值分割法的二维推广

FAN Jiu-Lun LEI Bo,<br>范九伦,
自动化学报 , 2009,
Abstract: One-dimensional minimum error thresholding method assumed that the histogram distributions of object and background are governed by a mixture Gaussian distribution. Considering the affects of noise and other factors on image quality, based on the assumption of a two-dimensional mixture Gaussian distribution, a two-dimensional expression of the minimum error thresholding method on the two-dimensional gray-level histogram is proposed. In order to improve the running speed, the fast recursive formulas are also given. Experimental results show that the two-dimensional minimum error thresholding method is a valuable image segmentation method, and can be well adapted to the images with noises and large variances between object and background.
Two-Dimensional Linear-Type Mnimum Error Threshold Segmentation Method
二维直线型最小误差阈值分割法

Fan Jiu-lun,Lei Bo,<br>范九伦,
电子与信息学报 , 2009,
Abstract: One-dimensional minimum error thresholding method assumes that the histogram distributions of object and background are governed by a mixture Gaussian distribution. Considering the affects of noise and other factors on image quality, based on the assumption of two-dimensional mixture Gaussian distribution, a two-dimensional linear-type minimum error threshold segmentation method is proposed on two-dimensional gray-level histogram. In order to improve the running speed, a fast recursive formula is also given. Experimental results show that the new method is a valuable image segmentation method which can be well adapted to the cases where the variances of the object and the background are distinctly different and contains noises.
Two-dimensional Cross-entropy Thresholding Segmentation Method for Gray-level Images
灰度图像的二维交叉熵阈值分割法

LEI Bo,FAN Jiu-lun,<br>,范九伦
光子学报 , 2009,
Abstract: Based on the explanation and illustration of the one-dimensional cross-entropy thresholding segmentation method proposed by Li & Lee,a two-dimensional cross-entropy thresholding method was proposed.Considering the disadvantage of high complexity and large computation of two-dimensional method,a fast recursive formula was presented also.Compared with the traditional two-dimensional Otsu's method,the new method can be better adapted to the cases that the variance between the object and the background is large...
Combined Method in Data Pretreatment Optimized by
基于混合遗传算法优化的数据预处理组合方法研究*

HAO Bo,WANG Lei,JING Xiao-dong,<br>郝,,景晓东
计算机应用研究 , 2005,
Abstract: In the course of data pretreatment,it's very difficult in finding the correct method of data pretreatment in terms of different data background and different characters.The combined method optimized by genetic algorithm based on simulated annealing method that combines the different estimative results of some mathematics solves this problem successfully.Simulation results of the combined method show that genetic algorithm based on simulated annealing method converges efficiently,approaches the best value quickly and improves the combined method's convergence efficiency and reliability.
Application of Genetic Algorithm in Hierarchical Structure Product Integer Conceptual Innovation Design
一种基于知识进化的多层次结构产品整体方案创新设计方法*

HAO Bo,WANG Li-xin,WANG Lei,<br>郝,王立新,
计算机应用研究 , 2005,
Abstract: Based on the genetic algorithm, a model of hierarchical structure product integer conceptual innovation design system is researched and proposed. In this paper, particular emphasis is placed on the fact that machine systems generally have hierarchical structures. Via treating those machines conceptual designs as design spaces to resolve, using the genetic algorithm, controlled its search process on the whole, a new hierarchical genotype representation is developed. In order to adapt this kind of representation, the genetic operators include of crossover operators and mutation operators, i.e., are newly constructed. Utilized the reproduction, crossover and mutation i.e. to iteration, a set of optimized design scheme are built automatically. A design example demonstrates this system is effective, exact and applied.
Precise advertised window adjustment based on TCP bandwidth control algorithm
基于精细广播窗口调整的TCP带宽控制算法

ZHANG Yi-bo,LEI Zhen-ming,<br>张轶,振明
重庆邮电大学学报(自然科学版) , 2005,
Abstract: 有效地控制TCP带宽对于改善TCP业务质量有着积极的意义。但是传统的TCP带宽控制算法较为复杂,增加了部署实施的难度。提出了一种精细的广播窗口调整算法(PAWA),用于对长时TCP连接的带宽进行控制。由于PAWA不需要对ACK报文进行延时处理,从而降低了实现的复杂程度,为TCP带宽控制算法的部署提供了可行的途径。仿真结果验证了PAWA算法的有效性和顽健性。 
Gray projection image stabilizing algorithm based on log-polar image transform
基于对数极坐标变换的灰度投影稳像算法

YU Bo,GUO Lei,ZHAO Tian-yun,<br>余,,赵天云
计算机应用 , 2008,
Abstract: Traditional gray projection image stabilizing algorithm just works under horizontal and vertical movement; but it is unable to deal with either scaling or rotation of the matched images. Due to the limitation, a gray projection image stabilizing algorithm based on log-polar image transform was introduced. When log-polar image transform was used in scaling or rotation image, the scaling or rotation movement in Descartes reference frame was represented by horizontal and vertical movement in log-polar reference frame. Accordingly, gray projection algorithm could be used in scaling or rotation image.
The effect of water media on the magnetic field of local magnetic objects
水介质对水下目标体磁场的影响

WANG Chuan-lei,QU Zan,SHEN Bo,<br>王传,曲赞,
地球物理学进展 , 2005,
Abstract: The magnetic field intensity caused by some similar magnetic objects in distinct media can produce certain modifications. This is measured and tested by a series of results about magnetic survey and verification obtained from Yangtze River channels. The modifications mechanism of magnetic field intensity from magnetic bodies in various media has not been discussed in this paper, but the phenomenon mentioned above can probably influence the effect on magnetic survey.
Phytoplankton assemblage and seasonal dynamics in the large oligotrophic Xinfengjiang reservoir in southern China
南亚热带大型贫营养水库浮游植物群落结构与季节变化——以新丰江水库为例

HU Ren,LEI La-Mei,HAN Bo-Ping,<br>胡韧,腊梅,
生态学报 , 2008,
Abstract: 新丰江水库是我国第四大的水库,也是广东省最大的水库和重要的水源地。于2004~2005年2月一次调查了新丰江水库水文、水质和浮游植物分布,分析了浮游植物群落季节动态特征。新丰江水库浮游植物生物量比较低,在0.037—1.497mg·L^-1之间变化。浮游植物种类较多,11次采样共检到158种。在丰度上,水库浮游植物主要以小环藻、蓝纤维藻、小球藻和纤维藻等优势种为主,而在生物量上则以微小多甲藻为优势。浮游植物组成随季节变化而不同,春季以硅藻、甲藻和绿藻为优势类群;夏季以蓝藻、绿藻和硅藻为优势类群;秋季蓝、绿藻减少而硅藻和甲藻增加。2004年的浮游植物季节性变化更为明显,有从硅藻-绿藻优势(2月和4月份),到蓝藻-绿藻优势(6月和8月份),到混合优势(10月份)和金藻优势(12月份)这样一个变化过程。2005年硅藻的相对丰度比2004年高出很多。两年浮游植物组成的差异与两年的降水量有关。水动力学对丰水期(6~8月份)浮游植物组成结构有较大影响,导致硅藻和绿藻相对丰度的增加。与温带贫营养型水库相比,新丰江水库的浮游植物群落具有春季和秋季种类多、夏季的蓝藻种类丰富的特点。从细胞大小分布上看,小于20μm浮游植物是生物量的主要贡献者,其次是大于45μm的浮游植物。在粒径小于20μm的浮游植物中,微小多甲藻是最主要的贡献者。浮游植物群落的大小分布受水动力学条件和营养盐浓度动态的影响。
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