基于BP神经网络的工业生态安全动态评价及障碍因子诊断

[目的]对安徽省工业生态安全进行评价和预测,为安徽省工业生态安全可持续发展提供科学依据.[方法]基于压力、状态、响应框架和生态、环境、经济、社会框架构建工业生态安全评价指标体系,采用聚类工具进行安全等级划分,结合熵权法和综合指数法评价2009-2018年安徽省工业生态安全水平,运用BP神经网络模型对2019-2025年...     

利用Kalman滤波和Hungarian算法的多目标奶牛嘴部跟踪及反刍监测

针对奶牛养殖场复杂环境下多目标奶牛嘴部自动跟踪及反刍监测困难的情况,该研究提出了一种基于嘴部区域跟踪的多目标奶牛反刍行为智能监测方法。在YOLOv4模型识别奶牛嘴部上下颚区域的基础上,以Kalman滤波和Hungarian算法跟踪上颚区域,并对同一奶牛目标的上颚和下颚区域进行关联匹配获取嘴部咀嚼曲线,以此获取反刍相关信息,从而实现多目标奶牛个体的嘴部跟踪和反刍行为监测;为解决奶牛快速摆头运动和棚舍栏杆遮挡引发奶牛标号变化的问题,提出未匹配跟踪框保持及扩大的方法。采集并选择实际养殖场环境下的反刍奶牛视频66段,对其中58段视频采取分帧操作得到图像,制作YOLOv4模型数据集,以其余8段视频验证跟踪方法和反刍行为判定方法的有效性。试验结果表明,YOLOv4模型对奶牛嘴部上颚、下颚区域的识别准确率分别为93.92%和92.46%;改进的跟踪算法可实现复杂环境下多目标奶牛嘴部区域的稳定跟踪,且有效解决了栏杆遮挡、快速摆头运动造成的奶牛标号变化现象,上下颚匹配率平均为99.89%,跟踪速度平均为31.85帧/s;由反刍行为判定方法获取的咀嚼次数正确率的平均值为96.93%,反刍时长误差的平均值为1.48 s。该研究可为实际养殖中多目标奶牛反刍行为的智能监测和分析提供参考,也可供其他群体动物运动部位的跟踪和行为监测借鉴。     

苹果采摘机器人果实识别与定位方法

提出了利用归一化的红绿色差(R-G)/(R+G)分割苹果的方法.对不同光照情况下拍摄的苹果图像进行了识别,并对识别后的图像进行预处理后,获得苹果的轮廓图像.对轮廓图像采用随机圆环法进行果实圆心、半径提取.通过建立基于面积特征与极线几何相结合的匹配策略实现双目视觉下的果实定位,对于搜索区域内面积相似的果实,通过计算垂直投影的互相关函数最大值的方法,得到排序基准线,然后根据顺序一致性原则进行匹配.实验结果表明:识别算法可以较好地消除阴影、裸露土壤等影响,识别率达到92%.采用随机圆环法,可以准确地提取果实的圆心、半径.在60～150 cm的距离范围内,测量误差小于2 cm.     

“云大— 120 ”浸种对水稻秧苗素质及产量影响的研究

试验结果表明：用“云大— 120 ”浸稻种对种子的发芽势、发芽率、秧苗素质、有效穗和稻谷产量具有一定的促进作用，发芽势比对照提高 12.68% — 23.94% ；发芽率提高 3.75% — 18.75% ；有效穗提高 0.5% — 7.43% ；产量增加 1.03% — 8.49% 。其使用方法简单易行，在生产上具有重要的推广价值。     

生物质结皮制剂在民勤流动沙区恢复植被的作用

利用矿物质材料和生物高分子材料的环境友好和吸湿保水的特性制作形成结皮,对立地条件极端恶劣的流动沙丘进行植被恢复.首先将草籽(黄蒿籽)撒播于目的沙丘表面,然后将与砂土混匀的结皮制剂均匀地撒在沙地表面,最后,洒木质素液使结皮凝固并用围栏封育试验区.通过调查结皮制剂施用后沙丘植物的种类、覆盖度、生长状况等植被恢复指标,分析了生物质结皮制剂在流动沙区植被恢复的效果.研究结果表明:结皮封育区内大量草籽萌发,达1000颗/m2;结皮区植物物种丰富度为13,对照区仅为2,物种多样性和均匀度指数也高于对照区,分别为1.57(Shannon-Weaver index H)、0.41(Simpson index D)和0.81(Pielou index),对照区则分别为0.47、0.40和0.68;结皮区植物生长期较对照延长,2010年早春提前10 d萌发,深秋枯黄延迟约20 d;结皮区植物在干旱季节亦可生长存活;2010年9月,结皮区沙丘植被盖度可达38%,对照区植被盖度仅为4%.研究结果表明该制剂可能在寒区旱区困难立地条件下的植被恢复工作中具有较大的潜在应用价值.     

Responses of labile soil organic carbon and enzyme activity in mineral soils to forest conversion in the subtropics

Aims

Globally, extensive areas of native forest have been almost replaced by plantations to meet the demands for timber, fuel material and other forest products. This study aimed to evaluate the effects of forest conversion on labile soil organic C (SOC), soil respiration, and enzyme activity, and to quantify their relationship in subtropical forest ecosystems.

Methods

Surface mineral soil (0–20 cm) was collected from a Cunninghamia lanceolata Hook. plantation, Pinus massoniana Lamb. plantation, Michelia macclurei Dandy plantation, and an undisturbed native broadleaf forest. Soil microbial biomass C, dissolved organic C, permanganate-oxidizable C, basal respiration, and six enzyme activities were investigated.

Results

Soil microbial biomass C was higher by 45.9 % in native broadleaf forest than that in M. macclurei Dandy plantation. The ratio of soil microbial biomass C to total SOC was 27.6 % higher in the M. macclurei Dandy plantation than in the native broadleaf forest. The soil respiration increased by 25.2 % and 21.7 % after conversion from native broadleaf forest to P. massoniana Lamb. and M. macclurei Dandy plantations respectively. The effects of forest conversion on the soil enzyme activities differed among the tree species. Soil microbial biomass C had higher correlation with soil respiration than with the other SOC fractions. Moreover, soil microbial biomass C was positively correlated with urease and negatively correlated with cellulase activity. Soil respiration had higher correlation with soil microbial biomass C, dissolved organic C and permanganate-oxidizable C.

Conclusion

Forest conversion affected the soil microbial biomass C, soil respiration, invertase, cellulase, urease, catalase, acid phosphatase, and polyphenol oxidase activities, but their response depended on tree species. Soil respiration was mainly controlled by labile SOC, not by total SOC.     

植酸酶对肉鸭饲用原料钙与磷及其养分真利用率的影响

在18种常用肉鸭饲料原料中添加750 U/kg的植酸酶,通过鸭的强饲代谢试验来探究植酸酶对钙、磷及干物质、粗蛋白、粗脂肪、能量等真利用率的改善程度。结果表明:与加酶前比较,加酶后供试原料的总磷真利用率的提高幅度为0.92%~17.29%,其中,对次粉2、麦麸、米糠、玉米总磷的提高幅度差异达到显著或极显著水平,分别为11.79%(P0.05)、8.46%(P0.05)、17.29%(P0.05)、16.33%(P0.01),其余原料的总磷真利用率均有不同程度的提高,但差异不显著(P0.05);对钙真利用率的提高幅度为2.74%~22.12%,其中,对碎米(早)、玉米皮、小麦、麦麸、棉粕的钙真利用率的提高作用显著(P0.05),分别为16.37%、17.12%、30.75%、21.40%、22.12%,对糙米(晚)的提高幅度最小,仅为2.74%,对其余原料的提高幅度均在5%以上;加酶后供试原料的干物质、粗蛋白、粗脂肪、能量真利用率的提高幅度分别为0.03%~14.60%,0.71%~27.05%,2.00%~37.69%、0.17%~10.07%;植酸酶对原料有效磷的改进值范围为0.02~2.60 g/kg。综合分析,在肉鸭饲料原料中添加750 U/kg的植酸酶,对钙、磷及干物质、粗蛋白、粗脂肪真利用率的改善效果较明显。     

定向刨花板加固腹板开洞竹木工字梁力学性能研究

为研究定向刨花板(oriented strand board,OSB)加固腹板开洞的竹木工字梁的力学性能,揭示其受力破坏机理。以孔径与腹板高度的比值(d/hw)和补强板型为参数,制作并测试了42根竹木工字梁,考察测试过程中的破坏形态、弯曲变形性能,分析各因素对工字梁力学性能的影响规律。结果表明,当孔径较小(d/hw≤25%)时,试件的破坏形态以翼缘内OSB层裂和腹板剪切破坏为主,孔洞对开洞梁承载力和刚度的影响较小,可忽略不计。当孔径较大(d/hw25%)时,破坏形态以洞口周边受拉和受压破坏为主,随着孔洞直径d增加,孔洞的不利影响愈发明显,开洞梁的承载能力呈下降趋势,但对梁的刚度影响较小。OSB补强板能有效约束孔角裂缝开展,加固后的开洞梁的开裂荷载、正常使用极限状态荷载和承载能力极限状态荷载较未加固开洞梁明显提高,平均提高52.9%、12.1%和28.2%。但OSB补强板对开洞梁抗弯刚度的改善作用不明显,平均提高仅为11.5%。承载力和刚度的提高幅度与补强板类型密切相关,其中,套环定向刨花板(collar oriented strand board,C-OSB)增强效果最好、双U型定向刨花板(two U shaped oriented strand board,TU-OSB)次之,U型定向刨花板(U shaped oriented strand board,U-OSB)最差。C-OSB适合于管道施工前对开洞梁进行加固,而U-OSB和TU-OSB适合加固d/hw不大于75%的开洞梁。粘贴OSB加固开洞竹木工字梁是一种有效的加固方法。     

Molecular cloning and sequence analysis of an LFY homologous gene from Juglans regia L.

The existence of a long juvenile phase is found seriously to affect the early-stage economic benefits of later mature walnuts (Juglans regia L.). Studies on LFY, a key gene controlling floral transition and flower differentiation, may be helpful in solving the problem. This study reports the identification and characterization of a JrLFY gene from Juglans regia L., a homolog of FLORICAULA/LFY. The gene was isolated from flower buds of precocious walnut cultivar Zhonglin No. 5 by RT-PCR and RACE. The cDNA sequence of JrLFY (GenBank accession no. GU194836) was 1496 bp and contained an ORF of 1158 bp. Its corresponding genomic sequence (GenBank accession no. HQ019159) showed that the JrLFY contained three exons and two introns. The predicted amino acid sequence of the gene consisted of 385 amino acids and had a conserved region in the C-terminal when being aligned with sequences of other LFY homologs. Phylogenetic analysis showed that the LFY protein of walnut was close to those of hickory and chestnut. These studies will lay a foundation for understanding the mechanism of early fruiting and preparation for transfer of the JrLFY as a transgene to later mature walnuts.     

三北地区大扁杏栽培管理实用技术

大扁杏是我国三北地区特有的经济树种之一。它适应性强,经济价值高。一般10～15年生杏平均收入1.5万元/(ｈ·ａ)。杏仁除含有多种营养成分外,还含有抗癌物质维生素Ｂ17,广泛应用于食品、医药等工业,是外贸出口产品,深受外商欢迎。栽植大扁杏是三北地区人民脱贫致富的一个?..