基于农业冷链物流的智能监测系统的设计与实现

在冷链物流的运输过程中,很多车辆因为生产年限较早,其环境保温的稳定性差,同时对车内环境的实时监控手段缺乏。所以这些冷链物流车辆在运输过程中农产品的生理状况难以监管,最终导致产品运输到目的地时可能已经处于腐坏状态。现有的装置体积较大,造价也不菲。所以我们设计一款便携,功能齐全,造价较低的冷链物流在线监管设备,其可以通过物联网传感器,对冷链车内的环境进行监控,方便农产品的运输。     

基于嵌入式linux的农业专家系统的开发与实现

为提高农业专家系统的使用率,使其可以被带到田间地头直接指导农业生产。主要研究便携式农业专家系统的开发和实现,特别是提出以图像采集作为专家系统人机交互的信息输入,并详细介绍摄像头采集图像过程,使农业专家系统指导农民生产更直接,使用更方便。     

PEMS与全流稀释系统试验对比研究

在轻型车排放试验室内,同时利用便携式排放测试系统(portable emission measurement system,PEMS)和全流稀释排放测试系统测量轻型乘用车排气污染物,通过对比排气污染物累积和瞬态测量结果,对比两种排放设备的差异。     

便携式土壤全氮测定仪性能研究

为研究土壤全氮含量,自主开发了基于近红外光谱技术的便携式土壤全氮测定仪.以中国农业大学上庄实验站采集的60个土壤样本作为实验材料,分别对土壤全氮测定仪的稳定性、准确性和预测模型精度进行了测试.使用模型的测定系数(RC)、验证系数(RV)、校正均方根误差(RMSEC)、预测均方根误差(RMSEP)和相对分析误差(RPD)作为模型精度的评价指标.实验结果显示,本测定仪在波长940、1 050、1 100、1 200、1 300、1 450和1 550 nm处的吸光度重复性误差分别为1.57％、1.80％、1.59％、0.94％、0.61％、0.64％和3.13％,平均误差1.80％;测定仪吸光度和傅里叶光谱分析仪吸光度相关系数分别达到0.971、0.948、0.928、0.873、0.920、0.901和0.913,平均值为0.922;使用测定仪平均吸光度数据,通过BP神经网络建立的土壤全氮预测模型Rc、RV、RMSEC、RMSEP和RPD分别达到0.81、0.80、0.029、0.019和3.44.使用该预测模型建立的土壤全氮分布图和实际土壤全氮分布图具有高度的一致性.实验结果表明,便携式土壤全氮测定仪工作稳定,使用平均吸光度数据建立的土壤全氮预测模型具有较好的预测能力和较强的鲁棒性,可以在土壤全氮含量实时检测中应用.     

便携式光合作用测定系统仪器误差探析

使用各种便携式光合仪测定植物单叶平均光合速率的总误差是由仪器误差、观测误差和叶片本身产生的某些光合反应综合而成。简析了因CO2 、流量、温度、气压等参数测量所用传感器的精度引起的仪器误差 ,且该误差因测量方式 (开路或闭路 )及叶片光合速率水平而异 ,光合强度越强其误差越小 ,误差变幅为 8%～ 2 0 % (开路 )或2 5%～ 15% (闭路 )。并分析了各测量参数误差对光合速率综合误差的贡献 ,指出仪器误差主要是由CO2 分析器和流量计误差所致     

普通手持式GPS接收机用于林区近实时差分定位的研究

ＧＰＳ接收机可实时、自动、全天候的确定空间内任一点的 3维坐标 ,因而是林业上的理想定位工具。由于美国政府实施ＳＡ(ＳｅｌｅｃｔｉｖｅＡｖａｉｌａｂｉｌｉｔｙ ,选择可用性 )政策 ,使得绝大多数条件下单机定位精度只有± 1 0 0ｍ的水平 ,这个精度远远不能解决绝大多数条件下的林区定位问题。因而研究提高ＧＰＳ定位精度的方法 ,不仅有理论意义 ,也有实用价值。目前 ,提高ＧＰＳ定位精度的主要手段有 :差分法、定轨法、延长观测时间法、软件处理法。学者们研究的热点仪器是ＧＰＳ中档次较高的单频机和双频机 ,这类接收机售价很高 ,在…     

Electrochemotherapy for the Treatment of Multiple Melanomas in a Horse

A 22-year-old Camargue mare was referred for showing signs of discomfort during chewing, building up of food in the mouth, and foul odor from the mouth. On physical examination, the mare presented bilateral pigmented labial masses affecting the upper and lower lips, more in the form of plaques at the mucocutaneous junction as well as multiple perivulvar and perianal lumps. The skin lesions were biopsied for histopathologic examination and the clinical suspect of melanoma was confirmed. The owner elected the lesions to be treated with electrochemotherapy using the drug cisplatin. After two sessions, the nodules were shrunk by 50% and the horse’s ability to feed normally was restored: at that time, the owner had the treatment discontinued because of financial issues. The horse is still in partial remission after 1 year from the end of the treatment. Electrochemotherapy can be successfully used to palliate large melanomas in horses.     

便携式光谱分析仪对叶菜失水程度的无损检测研究

利用自行研发的线性可调谐滤光片(LVF)便携式光谱仪对蔬菜失水程度进行了无损检测研究.通过获取小白菜、菠菜、叶菜生菜、油菜4种叶菜蔬菜叶片,分别在失水0h、失水12 h、失水24h、失水48 h的平均光谱曲线图进行对比分析.结果表明:蔬菜在失水过程中,便携式LVF光谱仪能有效快速反映其内部叶绿素的变化,并通过4种蔬菜叶片在同一个失水时间段下的光谱反射率曲线对比分析,表明利用便携LVF光谱仪可快速、无损的对叶菜类蔬菜失水程度的判别进行定性区分.与此同时,根据叶菜蔬菜叶片的光谱曲线构建蔬菜叶片叶绿素SPAD含量平均值综合预测模型,结果显示,叶菜类蔬菜叶片的平均光谱值在新鲜状态下的SPAD值建模相关系数为0.73,表明利用自行研发的便携式LVF光谱仪对叶菜类蔬菜叶片失水程度进行定量分析是可行的.     

Physiologic responses in healthy Labrador Retrievers during field trial training and competition

Ten healthy Labrador Retrievers (4 females and 6 males aged 3-6.5 years [mean, 4.5 years]) training with a professional trainer were studied. The dogs were in training during the entire study. Dogs were monitored within 5 minutes after retrieving birds on land and in water on 2 consecutive days during training and on 2 consecutive days at the Atlanta Retriever Club Fall Field Trial. Baseline samples were taken in the morning on a separate day before the dogs were loaded onto a truck. Venous samples were analyzed with a portable blood analyzer. Measurements included hematocrit, sodium, potassium, chloride, blood urea nitrogen (BUN), glucose, lactate, blood pH, Pco2, Po2, HCO3, and TCO2 plus rectal temperature, pulse rate, and respiratory rate. Ambient temperatures were recorded. Distances and times were estimated. Compared to baseline, significant increases occurred in rectal temperature, pulse rate, respiratory rate, chloride, lactate, and pH postexercise (P < .05): sodium, potassium, BUN, Pco2, and TCO2 were significantly decreased postexercise. Blood pH was markedly higher after retrieves on land than after retrieves in water. Estimated mean speeds were 11.4 mph (18.3 km/h) during a triple retrieve on land and 5.6 mph (9.0 km/h) during a retrieve in water. Maximal ambient temperatures were 84-86 degrees F (29-30 degrees C). In summary, Labrador Retrievers training with a professional trainer had evidence of hyperthermia, respiratory alkalosis, hypocapnia, and mild metabolic acidosis monitored within 5 minutes postexercise during training and field trial competition when maximal ambient temperatures were 85 degrees F (29 degrees C). The results provide a baseline against which physiologic responses of dogs with poor performance can be compared.     

手持式GPS三参数的确定

论述了影响手持式GPS精度的因素,并探讨了如何有效提高手持式GPS精度。着重阐述了空间直角坐标系之间的转换关系,并为实现这一转换进行了实践操作,在转换过程中运用了高斯投影的反变换、大地坐标系与空间直角坐标系之间的转换等诸多理论。成功地解算出了WGS-84坐标系与西安80坐标系之间转换的三参数,并且通过实测检验得到了较高的精度。