亚热带地区国有林场可持续经营问题研究

通过实地调研与文献研究,分析亚热带地区国有林场可持续经营存在的问题,结果表明:国有林场生产经营水平低、社会支持较少、政府管理及政策待完善是产生林地林权有争议、林下经济发展差、人才队伍建设水平待提高等问题的主要原因。故,从政府、社会、林场三方面提出促进国有林场可持续经营的针对性对策。国家社会科学基金项目(15BZZ071

Study and Modeling of Bi-Stochastic Fund Estimation for Rural Social Pension Insurance

社会保障制度是国家基本的社会经济制度，不仅在国民经济和社会和谐发展中占有重要地位，发挥着积极作用，而且事关千家万户的生计和每一个公民的福祉，为全社会所高度重视。尤其是农村社会养老保险制度的建立和推进，为我国社会主义新农村建设的顺利进行提供了有力的保障。然而无论是我国的城市社会养老保险还是农村养老保险都存在着一定的问题，特别是农村社会养老保险存在着各地条件不同，制度不同以及政府风险责任不明确的问题，需要进行改革和创新。近年来对养老保险制度的定量、精算研究已逐渐成为热点，但对总基金风险的定量估计却相对缺乏。基于以上背景，本文综合养老保险基金的筹集、运营和支付三个最基本也是最重要的方面，结合国内外先...Social Security is one of the essential economic and political systems. It takes an active role in the development of national economy and harmony society. And it is attached the importance by the whole people, because it is closed relative to the people’s lives. Specially, the establishment and development of rural social pension insurance system provide a strong guarantee to the processing of ne...学位：工学硕士院系专业：信息科学与技术学院自动化系_模式识别与智能系统学号：20043105

我国商业银行与外资银行合作探讨

在国际金融业并购的背景下 ,中国银行业面临入世后的竞争压力 ,吸收外资不仅能增强国内商业银行实力 ,更重要的是能给银行带来了先进的管理理念 ,把国内商业银行日益改造成符合国际标准的银行 ;对外资银行而言 ,与中资银行合作乃绕过管制 ,低成本向中国市场扩张 ,实现本土化发展战略的最佳选择

A clustering algorithm based on the grid2density and the spatial partition tree

摘要: 　基于密度的聚类是聚类分析中的一种,其主要优点是发现任意形状的聚类和对噪音数据不敏 感. 文章提出了一种新的基于网格密度和空间划分树的CGDSPT(Clustering based on Grid - Density and Spatial Partition Tree) 聚类算法. 其创新点在于,将数据空间划分成多个体积相等的单元格,然后基于单元 格定义了密度、簇等概念,对单元格建立了一种基于空间划分的空间索引结构(空间划分树) 来对数据进 行聚类. CGDSPT算法保持了基于密度的聚类算法的上述优点,而且CGDSPT 算法具有线性的时间复杂 性,因此CGDSPT算法适合对大规模数据的挖掘. 理论分析和实验结果也证明了CGDSPT算法的优点.Abstract : 　The density2based clustering algorithm is a sort of clustering analysis , its main merit is to discover arbitrary shape cluster and is insensitive to the noise data. This paper proposed a new clustering algorithm based on the grid density and the spatial partition tree CGDSPT. It is able to cluster data through dividing the data space into several unit cells. Some concepts , for example : the density , the bunch and so on , are defined on the unit cell. Then we established a spatial index structure for spatial division. The CGDSPT inherits the merit of the density2based clustering algorithm, moreover CGDSPT has the linear time2complexity , therefore it suits to the large2scale data mining. The theoretical analysis and the experimental result have also proven the merit of CGDSPT.资助项目:厦门大学“985”工程二期项目“国防信息化安全智能创新平台”资

Island instantaneous coastline extraction based on the characteristics of regional statistics of multispectral remote sensing image

本研究采用IkOnOS遥感图像,选取波谱特征区,通过区域像元统计并计算各波段权重系数,将影像进行波谱归一化处理,使归一化的影像岛陆与海水特征更明显。在此基础上,采用最大类间方差法确定最佳分割阈值,对归一化的影像进行二值化,从而提取海岛岸线。该方法采用特征曲线法进行水陆分离,得到的二值图像保持了原图的有效边缘,采用二值形态学提取的海岸线连续可靠、信噪比高。结果表明,该方法简单、快速,能有效提取海岸线,具有实用价值。This study adopted IKONOS remote sensing images and selected spectral characteristic areas, through regional pixel statistics and calculating weight coefficients of each band, processed the images with the spectral normalized method, which made the features of islands, land and water features more obviously in the images.On this basis, the OTUS was used to determine the optimal segmentation threshold, and the normalization image binarization was made, thus the island coastline was extracted.This method used the characteristic curve method to separate the land and water, obtained the binarization images and maintained the original edge effectively.The coastline that was extracted by Binary Morphology was continuous, reliable and high signal-to-noise ratio.The results showed that this method could extract the coastline fast, simply and effectively, which had the practical value

改良双袖套法大鼠原位肝移植500例

目的:改进大鼠肝移植的方法,缩短无肝期,提高手术成功率,总结大鼠原位肝移植经验.方法:正式实验分组:(1)预输注供者凋亡的脾细胞正常大鼠肝移植研究组(分4小组);(2)同期输注供者凋亡的脾细胞对正常大鼠肝移植研究组(分4小组);(3)术后输注供者凋亡的脾细胞正常大鼠肝移植研究组(分4小组);(4)预输注供者凋亡的脾细胞对肝硬化大鼠肝移植研究组(分4小组);(5)预输注供者凋亡的血液淋巴细胞对正常大鼠肝移植研究组(分3小组),每小组各10只大鼠.观察手术时间以及大鼠肝移植2d和1wk存活率.结果:在正式实验大鼠肝移植中,供体手术时间30±5min,供肝热缺血时间2±0.5min,袖套准备及肝脏修整时间10±2min,受体手术时间51±10min;无肝期16±4min.冷缺血时间61±5min.正式实验大鼠肝移植2d存活率96.8%(184/190),1wk存活率95.3%(181/190).结论:改进显露方法及肝上下腔静脉吻合方法后,手术简化,同时并发症减少,生存率提高

理想声源辐射声场的数值分析

通过声场的特性和规律分析可以识别和定位噪声源,对噪声控制以及声源的设计提供参考。数值方法是求解有源声场的重要工具,复杂的声辐射一般可分解为简单的声辐射叠加。研究了单极子、偶极子、活塞等几种理想声源辐射声场的解析解,并用有限元法计算数值解,得到相应的辐射声场,包括声压、速度、指向性等量,有限元法得到的数值结果与解析解吻合;利用有限元法计算了点声源的线性阵列与平面阵列等典型的叠加声场。对各种声源的特性和辐射声场的规律以及在工程领域中的应用进行了归纳。国家自然科学基金项目(51505261);;山东省自然科学基金项目(ZR2015AM013

MIMO channel identification using joint white noise statistics estimation and Kalman filtering

提出了一种新的时间选择性衰落环境下MIMO信道辨识算法。为了提高信息传输效率,训练序列被直接叠加于信息序列之上。算法将信息符号输出、接收端AWGN和由于采用零中频接收技术而产生的直流偏移当做虚拟的观测噪声,其均值和自协方差均未知。通过联合的递推白噪声统计估计器和卡尔曼滤波器对时变信道进行跟踪,推导了一种计算简单的次优无偏时变白噪声统计估计器。以简单有效的方法抑制直流偏移对辨识精度的影响。仿真结果表明了算法具有良好的性能。A novel scheme to perform multiple input multiple output (MIMO) channel identification in time -selective fading environments is suggested. In order to improve transmission efficiency, training sequences are arithmetically added to the information symbols. The output of information symbols ,additive white noises and dc -offsets at the receiver are regarded as fiction measurement noise, whose mean and autocovariance are both unknown.A time -varying measurement noise recursive estimator and Kalman filters cooperate to track the time - varying MIMO channel impulse response (CIR).A low complexity,sub -optimal and unbiased time-varying white noise statistics estimator is derived. Moreover, the influence of dc-offset is restrained in a simple way. Finally,it is compared with some existing methods, and all these indicate that the proposal exhibits good performance.国家高技术研究发展(863计划)项目(2006AA09Z108);; 国家自然科学基金资助项目(05C777

海上油田含聚生产水旋流气浮装置试验研究

旋流气浮装置是海洋石油平台含聚污水的处理装置。装置将管式旋流分离器与微孔气浮、溶气气浮技术相结合,结构紧凑,占地面积小,适用于海上采油平台。针对海上油田特点试制一套处理量为15 m~3/h工业化样机,并进行油田现场试验。现场试验表明,该装置能将污水含油质量浓度从494 mg/L降到46.3 mg/L,除油率为90.6%;固体悬浮物质量浓度从269 mg/L降到41 mg/L,除悬浮物能力为84.5%