排序方式： 共有14条查询结果，搜索用时 31 毫秒
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针对目前气动关节存在的缺点,提出了采用气动柔性驱动器(flexible pneumatic actuator,FPA)直接驱动,模拟人手指侧摆运动的侧摆关节。介绍了侧摆关节的工作原理。根据热力学第一定律,结合关节的动力学方程,推导建立了关节的转角及输出力矩的动态模型,并进行了仿真分析研究了关节的动态特性;试验研究了侧摆关节的动态特性,分析了关节转角及输出力矩的实际动态响应较慢原因;采用了串联双闭环控制方法,对关节的转角及输出力矩进行了控制研究,结果表明:期望角度为15°时,关节转角闭环动态响应时间约为0.3s,稳态相对偏差小于0.65%;期望输出力矩为188N?mm时,闭环输出力矩动态响应约为0.3s,稳态相对偏差小于1.5%。侧摆关节可控性高,可满足多指灵巧手关节设计要求。 相似文献
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基于特征金字塔注意力与深度卷积网络的多目标生猪检测 总被引：13，自引：12，他引：1
在生猪饲养环境中,猪只黏连、杂物遮挡等给生猪个体多目标检测带来很大困难。该研究以猪圈群养生猪为研究对象,以视频帧为数据源,提出一种适用于生猪形体检测的特征金字塔注意力(FeaturePyramidAttention,FPA)与Tiny-YOLO相结合的模型FPA-Tiny-YOLO。该模型将注意力信息融入到特征提取过程,在不大幅增加计算量的前提下即可提升特征提取能力、提高检测精度。对8栏日龄20～105 d的45头生猪视频截取图像进行图像处理,获得标注图片4 102张,构建了4种深度FPA模块分别加入YOLOV3与Tiny-YOLO模型中。试验表明,深度为3的FPA模块(即FPA-3)的Tiny-YOLO模型在测试集上对群养生猪多目标检测的召回率Recall、F1与平均检测精度m AP指标值最佳,分别达到86.09%、91.47%和85.85%,比未引入FPA模块的Tiny-YOLO模型均有不同程度的提高。选用不同的IOU(Intersection Over Union)和score阈值超参数值对模型预测结果均有不同程度影响;将测试集图像按照是否黏连与遮挡划分4种场景来探究该模型的鲁棒性。试验表明,加入FPA-3模块后Tiny-YOLO的Recall、F1与m AP比Tiny-YOLO分别提升6.73、4.34和7.33个百分点,说明特征金字塔注意力信息有利于精确、有效地对不同场景群养生猪进行多目标检测。研究结果可为后续开展生猪身份识别和行为分析移动端应用提供参考。 相似文献
3.
基于不同水平分辨率和边界层参数化方案的集合预报思路,应用花授粉算法与不限制负值的约束理论(FPA-NNCT)进行权重平均,提出一种新的风速集合预报模型(FPA-NNCT-WRF-E).利用山东省代表山地和海滨下垫面的2个风电场风速实测数据,将新模型与传统算术集合模型(M-WRF-E)以及FPA模型(FPA-WRF-E)的风速预报结果进行对比评估.结果表明:FPA-NNCT-WRF-E预报明显优于M-WRF-E和FPA-WRF-E的风速预报,与M-WRF-E相比, FPA-WRF-E将风速平均绝对误差(MAE)减小了20%以上,而新模型FPA-NNCT-WRF-E将MAE减小了38%以上.预报的准确性得到了提高. 相似文献
4.
M. Her D.‐H. Cho S.‐I. Kang J.‐S. Lim H.‐J. Kim Y.‐S. Cho I.‐Y. Hwang T. Lee S.‐C. Jung H.‐S. Yoo 《Zoonoses and public health》2010,57(3):155-161
Seven of 18 elk on a deer farm were found by the official Rose‐Bengal agglutination test (RBT) and tube agglutination test to be brucellosis reactors/suspects. Evaluation with the competitive ELISA (C‐ELISA) and the fluorescence polarization assay (FPA) tests revealed that six and five sera were positive respectively. The seven reactors/ suspects were slaughtered and their blood and tissues were collected. Brucella species could be isolated from three of the slaughtered animals, with nine isolates being obtained from the popliteal, supramammary and submandibular lymph nodes, vaginal discharge, mammary tissue and spleen. Brucella genus‐specific PCR based on 16S rRNA and AMOS‐PCR, which is specific for differential Brucella species, revealed that all nine isolates were Brucella abortus. These nine were further confirmed to be B. abortus biovar 1 by classical biotyping scheme assays. This is the first report of an outbreak of brucellosis in domestic elk in Korea. Our observations suggest that deer should be included in the routine Brucella surveillance programme for the effective control and prevention of brucellosis in Korea. 相似文献
5.
里氏木霉产纤维素酶条件的优化 总被引：3，自引：1，他引：2
研究采用里氏木霉菌株30911、40358和40359,设计了9个影响里氏木霉产纤维素酶活性因素,对里氏木霉的纤维素酶活性进行了液体摇瓶发酵试验。结果表明,培养基中微晶纤维素和小麦麸皮的最适添加量分别为:微晶纤维素20 g·L-1,小麦麸皮80 g.L-1,微晶纤维素与小麦麸皮最适配比为1:4;接种孢子悬液浓度1×107个·mL-1,培养温度28～30℃,pH 5.5,培养时间72 h,摇瓶转速180 r·min-1,250 mL三角瓶中装液量为50～75 mL。 相似文献
6.
Muma JB Lund A Nielsen K Matope G Munyeme M Mwacalimba K Skjerve E 《Tropical animal health and production》2009,41(5):723-729
The effectiveness of Rose Bengal test (RBT) and fluorescence polarization assay (FPA) in diagnosing cattle brucellosis in
endemic areas was assessed and RBT and FPA test agreement was compared (n = 319). The sensitivity of RBT and FPA in detecting
low Brucella titres were evaluated in paired sera (n = 34). A logistic regression model was constructed to predict cattle test result
in FPA using RBT as the main predictor and incorporating bio-data and animal history. There was 79.3% agreement between the
RBT and FPA (Kappa = 0.59; Std error = 0.05; p = 0.000) and a high correspondence between high RBT scores and positive FPA
results suggesting that sera with high RBT score may not require confirmation with tests such as competitive-ELISA or CFT.
High FPA cut-off points were more likely to miss animals with low antibody titres. The RBT had a reduced ability in detecting
low antibody titres compared to the FPA. FPA test interpretation was improved if a priori information, such as sex and age was used. Under the challenging disease surveillance conditions prevailing in rural Africa,
field-testing methods that are sensitive and specific; allow single animal contact, low technical skills in data interpretation
are suitable. 相似文献
7.
纤维素酶高产菌株的选育及产酶条件的研究 总被引：20，自引：0，他引：20
利用产纤维素酶的微生物分解废弃物(如农作物秸秆)不仅可以减少污染,还可以节省能源.该实验以康氏木霉TR为出发菌株,经过紫外线诱变,结合双层平板分离技术选育出1株纤维素酶活力明显提高的菌株TR6.并通过对康氏木霉固体发酵培养基、接种量、氮源、培养时间和培养温度等培养条件的研究,通过测定其所产纤维素酶的CMA和FPA酶活,找到了最佳的产酶条件.即:秸秆粉∶麸皮=1∶1,固液比=1∶3,添加硫酸铵为氮源,添加量为2%,接种量5%,30℃培养84h左右为宜.CMC,FPA酶活分别达到468.27U/g和275.31U/g. 相似文献
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[目的]筛选纤维素酶活力高的纤维素降解真菌,研究其粗酶活性.[方法]从土壤中分离、筛选高效纤维素降解菌,以透明圈试验和滤纸降解试验验证其降解能力,通过菌落菌丝形态及rDNA-ITS序列测序鉴定菌株种属,通过改变培养时间、氮源、装液量、起始pH及培养温度5个因素探讨纤维素降解真菌的最适产酶条件.[结果]得到3株纤维素降解真菌QS2、QS6和QW9,经鉴定确定QS2和QS6属青霉属(Penicillium),QW9为康宁木霉(Trichoderma koningii).QS6菌株的FPA酶活和CMC酶活在3个菌株中均表现活力最高,且最适产酶条件为32℃时氮源为磷酸铵、起始pH 6.0、装液量100 ml,培养时间14 d.[结论]高效纤维素降解真菌粗酶活性的研究为纤维素酶的发酵生产提供一定的技术支持. 相似文献
10.
在无"金标准"的情况下,为评估虎红平板凝集试验(RBT)、荧光偏振分析法(FPA)和间接酶联免疫吸附试验(I-ELISA)用于奶牛布鲁氏菌病的抗体检测能力,作者分别以RBT、FPA、I-ELISA3种方法对采自某奶牛场的血清样品进行检测,通过贝叶斯分析法对检测结果进行分析,研究3种方法检测奶牛布鲁氏菌血清抗体的敏感性(Se)和特异性(Sp)。结果显示,RBT、FPA、I-ELISA3种检测方法的敏感性(Se)分别为91.81%、95.92%和95.98%;特异性(Sp)分别为98.80%、86.54%和98.65%。本研究表明,3种血清学检测方法中以I-ELISA的检测能力最好。 相似文献