油松建筑材密度管理图的编制及其应用     

贾茜  贾忠奎  孙启越  张晓文  赵连清  谭红岩  迟明峰 《东北林业大学学报》2021,49(2):65-69

针对建筑材目的油松人工林经营措施,探讨不同生长发育阶段油松人工林密度调控下蓄积变化,为森林可持续经营提供科学依据。对河北平泉阳坡中土、阴坡中土和阴坡厚土3种主要立地类型的全生命周期油松人工林编制密度管理图,得出培育小、中、大径级建筑材措施。结果表明:河北油松建筑材林的培育,阳坡中土培育小径材、阴坡中土和阴坡厚土培育中大径材,期间经过2~3次间伐以达到高效培育的目的。阳坡中土林分,初植密度3 000~3 300株/hm2,10年生间伐强度12%,15年生强度20%,25年生强度25%,主伐时树高级为9~11 m,培育小径材。阴坡中土林分,初植密度2 700~3 000株/hm2,9年生间伐强度25%,19年生强度30%,主伐时树高级为9~11 m,培育中径材;初植密度2 200~2 500株/hm2,9年生间伐强度20%,17年生强度25%,27年生强度30%,主伐时树高级为11~13 m,培育大径材。阴坡厚土林分,初植密度2 000~2 300株/hm2,7年生间伐强度20%,15年生强度30%,主伐时树高级为11~13 m,培育中径材;初植密度1 000~1 200株/hm2,7年生间伐强度20%,13年生强度20%,23年生强度25%,主伐时树高级为13~15 m,培育大径材。  相似文献   

基于IMM UKF的冲量式测产系统研究     

赵博  赵士猛  安飒  刘阳春  汪凤珠  邢高勇 《中国农机化学报》2021,42(12):144

为适应精准农业的发展趋势,提高测产计量系统的精度,开发一套基于IMM UKF算法的冲量式测产系统。该系统由冲量传感器模块、北斗定位模块、DTU传输模块和上位机等组成。系统通过传感器模块进行信号的采集和处理,采用CAN通信方式将处理后的数据发送至上位机。上位机使用IMM UKF滤波算法对传感器上传的数据进行滤波,最终根据标定曲线得到谷物产量。通过车辆空载试验,采用IMM UKF算法与KF和UKF算法进行对比验证,结果表明IMM UKF算法的滤波效果更好,均方差为0.000 42 N。通过传感器标定试验,确定传感器的检测值与实际谷物重量的关系。通过大田测产试验,得出每个地块的产量分布图,试验结果表明该测产系统的平均误差达到3.911%。  相似文献   

基于深度残差网络的麦穗回归计数方法   总被引：2，自引：0，他引：2  

刘航  刘涛  李世娟  李路华  吕纯阳  刘升平 《中国农业大学学报》2021,26(6):170-179

单位面积的穗数是估算小麦产量的重要指标,针对传统麦穗计数方法效率低、主观性高等问题,将基于深度残差网络的密度回归模型引入麦穗的计数领域,建立原始图片与密度图的对应关系,以密度图像素值总和确定图像中麦穗数量。对ResNet34网络进行改进,提出了ResNet-16模型,实现端对端的麦穗计数。针对ResNet34网络复杂度高的特点,ResNet-16增加了残差块的宽度,减少了ResNet34网络的深度;为了避免真值密度图的精度误差以及梯度下降过快,引入了矫正因子δ和膨胀因子K。结果表明:改进后的ResNet-16模型能够取得更好的预测精度,平均绝对误差为2.50,均方根误差为3.27,相关系数R~2为0.973,计数准确率达到94%,较MCNN计数模型精度提高了6%,可以实现高效、快速的麦穗计数。利用基于深度残差网络的回归计数模型为麦穗计数提供了一种新的计数方式。  相似文献   

海洋渔业电子地图系统软件设计与实现   总被引：2，自引：0，他引：2       下载免费PDF全文

邵全琴 《水产学报》2001,25(4):367-372

系统地介绍了海洋渔业电子地图系统软件EA2000的数据模型和主要功能的设计与实现，EA2000采用了面向对象的数据模型，紧密的矢栅数据接口，以及图层－地图－图集一体化数据组织管理方法，该软件具有开放的数据输入接口，图层创作的自动化和动态交互式编辑，双向查询检索，缩放漫游与多级比例尺联动显示，动态显示，对象信息自动显示，地理信息系统渔船动态监控管理，多媒体信息插入管理，互操作等功能。  相似文献   

AFLP-based genetic linkage map of marine shrimp Penaeus (Fenneropenaeus) chinensis     

Zhaoxia Li  Jian Li  Qingyin Wang  Yuying He  Ping Liu 《Aquaculture (Amsterdam, Netherlands)》2006,261(2):463-472

This paper presents the genetic linkage map of the Chinese shrimp Penaeus (Fenneropenaeus) chinensis constructed with 472 AFLP markers. A hundred F₁ progeny from an intercross between a female from the new variety “Yellow Sea No. 1” and wild caught male used for the mapping study. Two separate maps were constructed for each parent. The female linkage map consisted of 197 marker loci forming 35 linkage groups and spanned a total length of 2191.1 cM, with an average marker space of 13.5 cM. The male map consisted of 194 marker loci mapped to 36 linkage groups and spanned a total length of 1737.3 cM, with an average marker spacing of 11.0 cM. The level of segregation distortion observed in this study was 12.2%. The estimated genome length of P. chinensis was 3150.3 cM for the female and 2549.3 cM for the male, respectively. The observed genome coverage was 69.6% for the female and 68.1% for the male map. The linkage maps constructed in this study provide basic information for further linkage studies on Chinese shrimp, and more importantly, the construction of the maps are part of the work of the genetic breeding programs which will be used for growth discovered in the QTL analysis of P. chinensis.  相似文献   

Haplotype phasing after joint estimation of recombination and linkage disequilibrium in breeding populations     

Luis Gomez-Raya  Amanda M Hulse  David Thain  Wendy M Rauw 《畜牧与生物技术杂志(英文版)》2014,5(1):38-52

A novel method for haplotype phasing in families after joint estimation of recombination fraction and linkage disequilibrium is developed. Results from Monte Carlo computer simulations show that the newly developed E.M. algorithm is accurate if true recombination fraction is 0 even for single families of relatively small sizes. Estimates of recombination fraction and linkage disequilibrium were 0.00 （SD 0.00） and 0.19 （SD 0.03） for simulated recombination fraction and linkage disequilibrium of 0.00 and 0.20, respectively. A genome fragmentation phasing strategy was developed and used for phasing haplotypes in a sire and 36 progeny using the 50 k Illumina BeadChip by： a） estimation of the recombination fraction and LD in consecutive SNPs using family information, b） linkage analyses between fragments, c） phasing of haplotypes in parents and progeny and in following generations. Homozygous SNPs in progeny allowed determination of paternal fragment inheritance, and deduction of SNP sequence information of haplotypes from dams. The strategy also allowed detection of genotyping errors. A total of 613 recombination events were detected after linkage analysis was carried out between fragments. Hot and cold spots were identified at the individual （sire level）. SNPs for which the sire and calf were heterozygotes became informative （over 90%） after the phasing of haplotypes. Average of regions of identity between half-sibs when comparing its maternal inherited haplotypes （with at least 20 SNP） in common was 0.11 with a maximum of 0.29 and a minimum of 0.05. A Monte-Carlo simulation of BTA1 with the same linkage disequilibrium structure and genetic linkage as the cattle family yielded a 99.98 and 99.94% of correct phases for informative SNPs in sire and calves, respectively.  相似文献   

Interactive mapping of urban tree benefits using Google Fusion Tables and API technologies     

Gregory D. Bowie  Andrew A. Millward  Nikesh N. Bhagat 《Urban Forestry & Urban Greening》2014,13(4):742-755

Geographic Information Systems (GIS) and web-based GIS platforms are typically used by large organizations and government agencies for the purpose of data storage, query, analysis, and spatial data mapping. Google Fusion Tables, however, provides cloud-based computing services for data management and easy user collaboration through the Google Maps interface. Fusion Tables are oriented towards smaller organizations that previously were unable to publish data online due to limitations of database knowledge, high cost of start-up, and restrictions on implementation. In this research project, we assess the functionality and limitations of Fusion Tables and associated API as a spatial data management system by programming an interactive web-based mapping platform, the CityTrees.ca Project, designed to showcase the benefits of trees growing on the campus of Ryerson University, Toronto. Specifically, Fusion Tables functionality, such as data storage and manipulation, is used to build a query interface (both attribute and spatial) that permits users of CityTrees.ca to search for and map trees by species, diameter, height, and location. We found that Fusion Tables performed well as a storage medium for our campus tree data, which could easily be explored through our creation of a JavaScript-enabled query tool. Our project provides a unique roadmap for small to medium-sized urban forestry organizations and environmental non-profits seeking to create interactive mapping applications where data privacy and advanced spatial analysis are not fundamental.  相似文献   

利用重组自交系群体定位玉米生育期相关性状QTL   总被引：1，自引：0，他引：1  

魏海忠  商伟  钟世宜  张彦军  徐长利  赵燕  王红红  刘保申 《玉米科学》2014,22(1):49-55

利用玉米自交系80007和80044为亲本,衍生包含355个家系的重组自交系(RIL)F9群体,采用SSR标记构建包括219个标记的连锁图谱,图谱总长度2 133.5 cM,标记间平均距离9.7 cM。采用完备区间作图法对控制玉米抽雄期、散粉期、吐丝期以及散粉至吐丝间隔期的4个生育期相关性状进行QTL分析。结果表明,共检测到60个QTL,其中抽雄期检测到20个QTL,吐丝期检测到15个QTL,散粉期检测到20个QTL,散粉至吐丝间隔期检测到5个QTL。共有7个QTL对表型变异的解释率超过了10%,表现为主效QTL效应,分布在第3、4和第9染色体。有11个QTL在不同环境中能重复检测出,是受环境影响较小、为较稳定的QTL。分析发现,生育期相关性状的QTL在染色体上有"成簇"分布的现象,并且贡献率较大的QTL控制着多个相关性状。结果表明,bin3.04-3.05、bin3.09、bin7.03和bin9.02-9.03是生育期相关性状QTL的密集区域,这些区域存在对生育期相关性状重要作用的位点。  相似文献   

水蜡蛾中国属及其地理分布     

张秀荣  郝蕙玲  杨集昆 《中国农业大学学报》1999,4(5):37-42

本文将水蜡蛾科（Brahmaeidae）的中国种归属问题进行了统一，并把外生殖器特征纳入属征，系统描述了各届特征和在中国的分布。  相似文献   

禽腺病毒贵州分离株ＨＳ—１的核酸酶切分析与蛋白抗原鉴定     

吴彤  韩丽珍  周碧君  李永明 《中国兽医杂志》2001,37(1):5-8

本研究利用１０％ＳＤＳ－ＰＡＧＥ及Ｗestern-Blotting技术鉴定３株不同的减蛋综合征病毒（贵州株ＨＳ－１、南京分离毒ＧＣ２、国际标准毒ＡＶ－１２７）的蛋白抗原性，结果表明，３株毒的蛋白多肽分子量均在１０６－１２kＤ范围,一各条多肽的组成上略有差异；它们都具有两条相同的免疫原性多肽，分子量分别为１０６和１００ＫＤ。同时，运用ＥcoRⅠ,HindⅢ，ＰｓｔⅠ和ＳmaⅠ等５种限制性内切酶进行了酶切分析，证实３株ＥＤＳ病毒用ＰstⅠ和ＳmsⅠ酶切的片段大小及长度略有不同，而其它３种酶的酶切图谱完全相同。  相似文献