面向工业混杂系统故障检测的扩展数据逻辑分析方法

常规的数据驱动故障检测方法难以处理同时包含连续和离散变量的工业混杂系统,数据逻辑分析(logicalanalysisofdata,LAD)方法通过对历史数据中变量组合的逻辑分析,能够有效地挖掘离散和连续变量数据中存在的隐含规则。然而,常规的LAD在提取连续变量特征时存在对趋势变化信息丢失的问题,并且在处理具有高维度、多变量特征的工业数据时会导致提取的规则存在大量冗余。为此,本文提出一种基于扩展数据逻辑分析(extendedlogicalanalysisofdata,ELAD)的工业混杂系统故障检测方法,根据与关键变量的关联度选取相关变量,增加变量的趋势信息以进行过程状态变化的表征,生成可解释的故障检测模型。应用于工业煤气化汽包过程,有效地检测了关键混杂变量对汽包液位故障的影响,实验结果验证了所提方法的可行性和有效性。

High‐sensitivity distributed dynamic strain sensing by combining Rayleigh and Brillouin scattering

The phase-sensitive optical time-domain reflectometry(φ-OTDR)is a good candidate for distributed dynamic strain sensing,due to its high sensitivity and fast measurement,which has already been widely used in intrusion monitoring,geophysical exploration,etc.For the frequency scanning basedφ-OTDR,the phase change manifests itself as a shift of the intensity distribution.The correlation between the reference and measured spectra is employed for relative strain demodulation,which has imposed the continuous measurement for the absolute strain demodulation.Fortunately,the Brillouin optical time domain analysis(BOTDA)allows for the absolute strain demodulation with only one measurement.In this work,the combination of theφ-OTDR and BOTDA has been proposed and demonstrated by using the same set of frequency-scanning optical pulses,and the frequency-agile technique is also introduced for fast measurements.A 9.9 Hz vibration with a strain range of 500 nεhas been measured under two different absolute strains(296.7μεand 554.8με)by integrating the Rayleigh and Brillouin information.The sub-micro strain vibration is demonstrated by theφ-OTDR signal with a high sensitivity of 6.8 nε,while the absolute strain is measured by the BOTDA signal with an accuracy of 5.4με.The proposed sensor allows for dynamic absolute strain measurements with a high sensitivity,thus opening a door for new possibilities which are yet to be explored.

建筑增强专用聚丙烯腈纤维的耐环境性研究

模拟土工建筑材料沥青及混凝土实际应用中的酸碱性和日晒环境,研究建筑增强专用聚丙烯腈(PAN)纤维的耐环境性,并与普通PAN高强纤维进行对比。结果表明:相较于普通PAN高强纤维,建筑增强专用PAN纤维在1732 cm^-1处C=O伸缩振动峰较弱,并且结晶度和晶区取向度较高;经35 d日晒雨淋后,建筑增强专用PAN纤维的断裂强度和初始模量的保留率最高分别达到98.07%和96.43%;在50℃的极端酸性环境(pH值为1)中,建筑增强专用PAN纤维的断裂强度和初始模量的保留率均大于98%;建筑增强专用PAN纤维的热分解温度高于普通PAN高强纤维100℃以上;建筑增强专用PAN纤维的耐候性、耐酸碱性和耐热性均比普通PAN高强纤维好,能够更好地满足建筑材料的使用要求。

双金属Ag-Ni-MOF-74的合成及低温CO催化还原NO性能研究

采用后合成修饰法成功制备出一系列双金属Agx-Ni-MOF-74催化剂,并应用于CO选择性催化还原NO(CO-SCR)反应.研究结果发现,相较于单金属Ni-MOF-74催化剂,双金属Ag-Ni-MOF-74具有更加优良的低温CO催化还原NO能力,其中Ag1-Ni-MOF-74催化剂在200~300℃的温度范围达到接近100%NO转化率.利用X射线衍射分析(XRD)、傅氏转换红外线光谱分析(FT-IR)、场发射扫描电子显微镜(SEM)、X射线光电子能谱(XPS)、氢气程序升温还原性能测试(H_(2)-TPR)等技术对样品的结构和性能进行了探究,发现Ag的加入有利于丰富催化剂活性位点和提高催化剂的比表面积,并促进反应物的有效活化和传输.此外,基于原位红外光谱分析,发现了CO-SCR反应过程遵循具有较高低温催化效率的Langmuir-Hinshelwood(L-H)机理.

Development of transplanting manipulator for hydroponic leafy vegetables

The production of hydroponic leafy vegetable plug-seedlings uses coco-peat as culture substrate in South China.Coco-peat has lowered density than peat-moss,and the friction between substrate block and pickup tool is small.So,it is hard to pick up in mechanism transplantation.In order to increase the friction,the existing transplanting manipulator had relatively complex structures.To simplify the structure of transplanting manipulator and improve the stability of picking up substrate block,four stainless steel fingers with rectangular cross-section were used in this research.A vertical driving was used to realize the coupling effect that could insert and shrink at the same time,by applying different combination of constraints to the steel fingers.This could increase friction between the steel fingers and the substrate block,and then enhance the stability of the substrate block.Different combinations of constraints were applied to the rectangular stainless steel fingers(3 mm×0.8 mm).The working videos of steel fingers were taken by high-speed photography.High-speed motioned analysis software was used to acquire and analyze traces of steel fingers movements.When the length which top end of the steel fingers moved outward(M)is equal to 1.5 mm,the length which guiding part widened(N)is equal to 1 mm,the shrinking distance of steel fingers is 4.2 mm.In this research,16-day hydroponic leafy vegetable plug-seedlings were used for performance,which cultivated with coco-peat substrate with the moisture in the substrate at 81%.The transplanting manipulator was attached to a Denso robotic arm to conduct transplanting performance test.When the shrinking distance of steel fingers increased from 0 mm to 3.2 mm and the inserting angle decreased from 80°to 77°,the lifting force of substrate block increased by 118%from 1.45 N to 3.16 N.However,excessive shrinkage stirred the substrate block,which would reduce the friction between the substrate block and pickup parts and lowered the lifting force of pickup part in the substrate block.The experimental results also demonstrated that when the shrinking distance of the steel fingers reached 3.2 mm and the root distribution rate reached 46%,the success rate of transplantation was 80%.When the leafy vegetable plug-seedlings root distribution rate reached 92%,the success rate of transplantation was 96.67%.The degree of root distribution rate was positively correlated with the transplantation success rate.Therefore,in order to ensure an acceptable success rate of transplantation,the root distribution rate of leafy vegetable plug-seedlings should be at least 90%.This study provides a technical reference for developing simplified transplanting manipulator that can be used to transplant the hydroponic leafy vegetable plug-seedlings with coco-peat as the culture substrate.

Development of a high-productivity grafting robot for Solanaceae

Grafting is a green,environmentally friendly,and sustainable way to prevent soil-borne diseases.Although artificial grafting is the main grafting approach used for grafting production,it has some problems which are low productivity,unstable operating quality and labor-intensive.Hence,some countries have been engaged in the development of grafting robots for the past two decades;however,the productivity of these grafting robots has no advantage when compared to artificial grafting.This study aims to develop a high-productivity grafting robot(HPR)for Solanaceae.To improve grafting productivity,this paper adopted plug trays to feed crown-removed rootstocks automatically and carried out multi-plant simultaneous grafting to improve grafting productivity and extensibility.Manipulators were employed to take out rootstocks,increase the distance between them,and transfer them to transfer cups for the simultaneous multi-plant grafting.At the same time,negative pressure mechanisms were designed for speeding up the auxiliary feeding of root-removed scions.Although the HPR was designed in a two-operator mode,a one-operator mode can also be implemented by adjusting the control program.Tests were conducted by varying the artificial feeding speed to analyze the performance of the grafting robot.The results showed that the productivity of the robot in the two-operator mode was 2250 plants/h,and 1542 plants/h in one-operator mode;comparing the artificial feeding productivity with auto grafting productivity,it was found that the capacity of the grafting robot was higher than the feeding speed of the one-operator mode but lower than that of the two-operator mode.

Pneumatic separation system for collected seedlings using subdivided air streams

To adhere to the needs of automated supply of collected seedlings for mechanized grafting and cutting machines for enhancing their operational efficiency,herein,a separation system that uses subdivided air streams to separate the collected seedlings is developed.The separation system comprises a feeder for supplying collected seedlings,a seedling separator that uses subdivided air streams,a picking belt for the separated seedlings,a delivery unit for the separated seedlings,a pneumatic unit,and a control unit.To investigate the complete performance of separation,picking,and delivery of the separation system,several separation experiments were conducted to separate the collected Anthurium seedlings.The results show that the consistency of the moving direction of seedlings floated by subdivided air streams in the separation container and the moving direction of the picking belt have a significant effect on the picking of the separated seedlings by the picking belt.Moreover,the seedling supply timing of the feeder has a significant effect on the stability of the collected seedling separation rate during continuous separation.When this timing is such that the percentage of separated seedlings is 70%,the separation rate of continuous separation operation is 2.24 plant/s(the separation productivity is 8060 plants/h)with 0.12 CV.The operating conditions are 0.5 MPa separation pressure,0.5 s nozzle operation time,and 60 mm seedling thickness in the separation container.Moreover,the staying times of the collected seedlings separated in the separation container are less than 2.5 min.

Modulating Myofibroblastic Differentiation of Fibroblasts through Actin-MRTF Signaling Axis by Micropatterned Surfaces for Suppressed Implant-Induced Fibrosis

Myofibroblasts,the primary effector cells for implant-induced fibrosis,contribute to this process by secreting excessive collagen-rich matrix and contracting.Thus,approaches that suppress myofibroblasts may achieve desirable suppression effects in the fibrotic process.As one of the important physical properties of materials,material topographical structures have been proven to affect various aspects of cell behaviors,so is it possible to manipulate the formation of myofibroblasts by tailoring the topographical properties of medical devices?In this study,polycaprolactone(PCL)surfaces with typical micropatterns(micro column and micro pit)were fabricated.The regulatory effects of surface micropatterns on the myofibroblastic differentiation of fibroblasts were investigated.Compared to the flat surfaces and surfaces with micro pit,surfaces with micro columns triggered the F-to G-actin transition,inhibiting the nuclear transfer of myocardin-related transcription factor-A.Subsequently,the downstream geneα-smooth muscle actin,which is a marker of myofibroblasts,was suppressed.Further in vivo investigation showed that PCL implants with micro-column-patterned surfaces inhibited the formation of peri-implant fibrotic capsules.Our results demonstrate that surface topographical properties are a potent regulator of fibroblast differentiation into myofibroblasts and highlight the antifibrotic potential of modifying surfaces with micro-column patterns.