自然条件下番茄成熟度机器人判别模型

针对机器人采摘番茄因用途不同而进行选择性收获的问题,对人工选择的番茄图像样本集进行特征分析,从番茄的摄像机透视几何出发,提出将番茄表面红色调所占着色面积比与其他色调所占着色面积比的差值作为描述番茄成熟程度的主要分组特征。利用该特征并结合番茄着色区域整体色调均值和方差,用BP神经网络建立番茄成熟度的判别模型。通过模型测试和噪声水平测试表明,将着色面积比差值和色调均值作为模型的两个输入时,模型的准确判别率和抗干扰能力都是最佳的。模型测试的准确判别率为97.5%,当噪声水平在0.05以下时准确判别率可达到95.26%以上,可以为番茄自动收获作业提供一定的理论参考依据。     

冷板冷藏汽车冷板强化换热放冷过程数值模拟

利用建立显热容法模型,对板内共晶冰融解过程进行了数值模拟,研究了冷板和在冷板外表面添加翅片、内部添加肋片等方式对冷板放冷时间的影响和内部温度场的分布。研究结果表明,冷板内共晶冰融解不均匀,放冷结束时,板内仍有大量的共晶冰未融解,造成冷量浪费;在冷板外表面添加翅片可缩短放冷时间,但内外温差较大;在冷板内部布置肋片,可使板内冷量均匀放出,板内蓄冷剂温度分布均匀,冷板放冷时间延长,达到节能的目的。     

基于神经网络技术的乘员体型识别系统

BPMS(Body Pressure Measurement System)系统是针对汽车安全气囊系统设计的辅助系统。本系统应用神经网络技术,通过对座椅压力传感器信号的分析处理,识别出车内乘员的体型特征,从而辅助控制车辆安全气囊的爆发。BPMS系统由试验台架设计、座椅压力采集、数据预处理、乘员体型识别系统等部分组成。试验结果表明,该系统可以有效地识别乘员体型特征,为准确控制安全气囊系统的工作提供保障。     

Comparison of 2 methods for inducing iPSC to differentiate into neural stem cells

AIM: To select an efficient way of promoting induced pluripotent stem cells (iPSC) to differentiate into neural stem cells (NSC) by comparing 2 methods. METHODS: The culture system in method A contained SB431542 (5 mmol/L) and drosomophorin (5 mmol/L) with 100% initial cell density, while that in method B contained SB431542 (5 mmol/L) and drosomophorin (1 mmol/L) with 30%~50% initial cell density. For comparison and identification of the 2 methods, the growth state was observed under microscope, and the expression of Pax6, nestin, Sox1 and Sox2 was quantitatively detected by real-time PCR and flow cytometry. The related protein expression and the ability of spontaneous differentiation were determined by immunofluorescence analysis. RESULTS: The cells derived from method A with 5 mmol/L of SB431542 and drosomophorin and 100% initial cell density achieved the higher expression of Pax6, nestin, Sox1 and Sox2. The growth state was better and the cells differentiated into neurons and astrocytes normally. CONCLUSION: The method A was superior to method B, and we recommend the method A with 5 mmol/L of SB431542 and drosomophorin and 100% initial cell density as the method for differentiating NSC.     

Discriminating power of selected physical properties of seeds of various rapeseed (Brassica napus L.) cultivars

In this study, the seeds of open-pollinated winter rapeseed cultivars, hybrid winter rapeseed cultivars, open-pollinated spring rapeseed cultivars and hybrid spring rapeseed cultivars were investigated. The physical, optical, mechanical, geometric and image texture properties of rapeseeds were compared. Statistical models were developed based on the analyzed parameters to discriminate between seed groups. Most parameters effectively discriminated between cultivars of winter and spring rapeseed, including true density, porosity, L*, a*, b*, and spectral values at 400 nm, 470 nm, 500–530 nm, 560–620 nm, 640–650 nm and 690 nm. Four homogeneous groups were identified based on linear dimensions: F (surface area), S (width) and shape factors W₆ (circularity ratio), Rb (Blair-Bliss coefficient) and W₁₃ (roundness). No statistically significant differences in the mean values of hardness or area under the force-displacement graph were observed between seed groups. The model developed based on image texture variables from channel Y (luminance) was characterized by the highest discrimination accuracy of 82–87%. The experimental groups were classified with 89–92% accuracy in the model combining the best variables from each group of physical parameters. Total classification accuracy in neural networks reached 75% for a validation set comprising geometric properties and 91–92% for a validation set containing physical characteristics.     

Validation of a Reversible Lameness Model and the Assessment of a Topically Applied Nonsteroidal Anti-Inflammatory Drug

The objective of this study was to validate and use a model of reversible foot lameness in the horse. The model used both forelimb hooves fitted with a clamp. After force platform baseline measurements, one clamp was tightened to induce an asymmetry index (ASI) between 25% and 30% and left in place for 120 hours. Serial force platform measurements were obtained. After 120 hours, the clamp was released, and force platform data were recorded until the horse returned to soundness. The procedure was repeated on the opposite forelimb. To use the model, the same procedure was performed in another group of horses with one limb treated with topical diclofenac at 12-hour intervals beginning when the initial ASI was between 25% and 30% and continued for 120 hours. The response was evaluated for each outcome variable using linear mixed models. Time (duration of clamp being tight), limb (left or right), and clamping order (first or second foot) were fixed effects, whereas horse was a random effect. A similar analysis was completed with the additional variable (diclofenac treatment) for the model utilization data. For model validation, the only significant force plate data variable was time, which is consistent with model design. For model utilization, there was a significant effect of time and a significant decrease in the ASI associated with topical diclofenac. The model created a consistent lameness that will provide a mechanism to compare treatments for pain and lameness. Topical diclofenac applied twice daily decreased the lameness associated with the model.     

可降解育苗杯自动装盘机的设计

介绍了创新设计的自动装盘机的工作原理、主要结构及性能参数，该机可提高现有林木育苗装播线的生产效率和自动化水平，满足实际生产需要。     

Studies on the Development and Quality of Fish Chiffon Cake and its Storage Stability

Thirty percent flour was substituted with dolphinfish (Coryphaena hippurus) and unicorn leatherjacket (Aluterus monoceros) paste in a cake recipe to evaluate the quality and shelf life of fish chiffon cakes stored at 4℃ and 25℃. Proximate composition, free amino acid (FAA), aerobic plate count (APC), total volatile basic nitrogen (T-VBN), and texture profile and sensory evaluation of fish chiffon cakes were conducted. Fish paste addition increases proteins. Cakes made with dolphinfish paste had the highest FAA content, followed by the cake made with unicorn leatherjacket. Histidine is the predominant FAA in dolphinfish chiffon cake, and it is significantly higher than the other two cakes. T-VBN values and APC increased with the addition of fish paste and was lower than the upper limit of acceptable fish products during storage period. The hardness of the two fish cakes was slightly lower than the control after 1 and 2 days storage at 25℃ or 3 and 5 days storage at 4℃ and increased during storage. Sensory evaluation showed no significant differences among the ordinary cake and two fish chiffon cakes for odor, texture, flavor, and overall acceptability. Therefore, incorporation of white fish meat is feasible for chiffon cake.     

普通T形骨板治疗玩具犬桡尺骨远端骨折的手术效果

旨在评估普通T形骨板内固定治疗玩具犬桡尺骨远端骨折的临床效果及并发症。回顾了在中国农业大学动物医院采用开放式复位和普通T形骨板内固定治疗桡尺骨远端骨折的玩具犬的病历记录,并对这些病例进行回访。入选病例满足：体重不超过7 kg;骨折位置位于前臂远端(远端骨段与桡骨长度比值<0.25);回访时间>12个月;病例信息记录完整。结果表明：共纳入29只犬的29例桡尺骨远端骨折,26例(89.7%)术后无跛行,3例(10.3%)术后勉强可见跛行。未发生严重并发症,轻微并发症的发生率是20.7%(n=6)。普通T形骨板内固定能有效治疗玩具犬桡尺骨远端骨折,临床效果良好,无严重并发症。     

Minimally‐invasive plate osteosynthesis of a Salter‐Harris type 2 fracture of the proximal phalanx in a filly

A 7‐month‐old Warmblood filly was referred to the equine hospital because of a Salter‐Harris type 2 fracture of the proximal physis of the right hind P1. On admission, the filly had acute grade 3/5 lameness at the walk and diffuse swelling in the area of the right hind proximal phalanx. Radiographs were taken to assess the fracture and plan treatment. Surgical treatment using two 4.5 mm narrow locking compression plates (PIP‐LCPs) resulted in fracture stabilisation and rapid healing. This case report suggests that internal fixation using PIP‐LCPs is useful for the treatment of Salter‐Harris type 2 fractures of the proximal physis of P1 in large foals.