基于Bagging-WOA-SVR的粮堆温度场预测模型

采用阵列式分布的测温电缆检测粮仓温度变化情况,利用机器学习技术来预测粮食温度,用粮仓1年监测数据来预测粮堆未来27 d温度。传统的BP、RBF、RF、SVR单模型对粮堆温度进行预测存在误差大、泛化能力差等缺点,提出一种基于Bagging集成的鲸鱼算法优化支持向量回归模型(Bagging-WOA-SVR),并与灰狼算法优化支持向量回归模型作比较。将影响粮堆温度的多种因素做灰色关联分析,选取粮仓内温度、粮仓内湿度、粮仓外温度、粮仓外湿度、粮仓平均温度、地表温度作为神经网络的输入,粮堆平均温度作为预测输出,选取3个指标为评判标准,对比分析模型预测精度。结果表明:提出的Bagging-WOA-SVR模型相比之下有着较好的稳定性,均方误差为0.24,相关系数为0.9892。

In-plane spin excitation of skyrmion bags

Skyrmion bags are spin structures with arbitrary topological charges, each of which is composed of a big skyrmion and several small skyrmions. In this work, by using an in-plane alternating current(AC) magnetic field, we investigate the spinwave modes of skyrmion bags, which behave differently from the clockwise(CW) rotation mode and the counterclockwise(CCW) rotation mode of skyrmions because of their complex spin topological structures. The in-plane excitation power spectral density shows that each skyrmion bag possesses four resonance frequencies. By further studying the spin dynamics of a skyrmion bag at each resonance frequency, the four spin-wave modes, i.e., a CCW-CW mode, two CW-breathing modes with different resonance strengths, and an inner CCW mode, appear as a composition mode of outer skyrmion–inner skyrmions. Our results are helpful in understanding the in-plane spin excitation of skyrmion bags, which may contribute to the characterization and detection of skyrmion bags, as well as the applications in logic devices.

肺缺血再灌注细胞模型的建立及Bag-1表达

目的 建立肺缺血再灌注细胞模型并研究BCL-2结合抗凋亡基因(BCL-2 associated anthanogen-1,Bag-1)在肺缺血再灌注中的表达,以期为研究Bag-1在肺缺血再灌注疾病的作用机制提供实验基础。方法 本课题以A549细胞系作为肺缺血再灌注模型的细胞模型,实验分5组,将A549细胞给予不同缺氧时间:0 h、6 h、12 h、18 h、24 h缺氧,再复氧24 h处理后,通过低温、低氧、葡萄糖剥夺建立缺血再灌注细胞模型。通过比较5组细胞活性、乳酸脱氢酶(lactate dehydrogenase,LDH)以及活性氧自由基(reactive oxygen species,ROS)水平,确定建模效果,同时观察Bag在肺缺血再灌注中的表达。结果 不同缺氧时间处理后,缺氧组细胞活性均较正常组细胞活性降低(P<0.01),并随缺氧时间延长细胞活性下降,各时间点间细胞活性存在显著差异(F=85.03,P<0.001)。缺氧组LDH、ROS浓度均较正常组细胞明显升高(P<0.01),各时间点间LDH(F=107.67,P<0.001)、ROS(F=42.61,P<0.001)水平具有统计学意义,Bag-1表达在缺氧6 h时最高,后随时间延长水平逐渐下降。结论 以A549细胞系作为模型细胞,以低温、低氧、葡萄糖剥夺为方法可成功建立缺血再灌注细胞模型,Bag-1在缺血再灌注损伤中表达趋势为先升高,再降低。

含BAG-nMgO的新型牙科复合树脂的抗菌及再矿化性能研究

目的:联合应用生物活性玻璃(BAG)和纳米氧化镁(nMgO)改性牙科光固化复合树脂,以获得兼备优良的抗菌性及再矿化性能的新型牙科复合树脂。方法:将不同含量的BAG(2.5 wt%、7.5 wt%、12.5 wt%)和2.5 wt%nMgO引入牙科光固化复合树脂中,制备成含BAG-nMgO的实验树脂,并以卡瑞斯玛复合树脂作为对照。通过菌落计数、代谢活性分析(MTT)和活/死细菌染色,评价实验树脂的抗变形链球菌(S.mutans)能力;将脱矿人牙牙本质片及实验树脂在模拟体液(SBF)中浸泡21 d后,通过扫描电子显微镜(SEM)和X射线能谱仪(EDS)观察分析脱矿牙本质表面形貌和元素组成,评估实验树脂再矿化特性;通过万能试验机、维氏硬度仪等测试树脂的固化深度、压缩强度及维氏硬度。结果:实验组树脂的抗S.mutans活性显著高于卡瑞斯玛对照组,且与BAG的含量相关;当BAG添加量为7.5 wt%时,脱矿牙本质开始矿化;BAG添加比例为12.5 wt%时,可见厚的矿化层,牙本质小管几乎被完全封闭;实验组的固化深度均显著高于卡瑞斯玛,维氏硬度优于或与其相近,随着BAG比例的增加,各实验组的固化深度、压缩强度间无显著性差异。结论:BAG和nMgO的联合应用提高了实验树脂的抗菌性,并赋予其再矿化性能。新型复合树脂预期可减少细菌入侵和促进早期龋损的再矿化。本研究为新型多功能复合树脂的研究开发提供了理论依据和研究基础。

基于BS_Bagging-cLightGBM模型的电动汽车故障预测方法

针对因电动汽车故障数据样本类别不平衡引起的机器模型分类性能欠佳、故障查全率低的问题,本文提出一种以LightGBM为基学习器改进的Bagging集成电动汽车故障预测模型:在Bagging集成学习中使用Borderline_SMOTE方法对训练集重新采样,改善训练子集的数据不平衡程度,避免小类样本信息缺失;将权重系数和正则化项嵌入LightGBM基学习器的损失函数中,提高训练中小类样本的错分类代价。实验结果表明,该模型可有效提高故障查全率、宏平均和AUC值,其中AUC值达到0.898 4,故障样本的查全率为0.808 3,在电动汽车不平衡数据集上的故障分类性能显著优于传统单一模型和其他对比算法。

BAG3蛋白在心脏疾病中的研究进展

Bcl-2相关永生基因3(Bcl-2 associated athanogene 3,BAG3)是一种多功能的细胞保护蛋白,也被称为CAIR-1(CAI stressed-1)/Bis(BCL-2 interacting cell death suppressor)。BAG3在心肌和骨骼肌中高表达,发挥多种生理学功能,如维持Z盘的稳定性、减少心肌细胞凋亡,调节蛋白质量控制系统、线粒体稳态以及心肌收缩力等。BAG3和扩张型心肌病、心力衰竭、限制型心肌病、Tako-Tsubo心肌病等多种心脏疾病的发病有关。调控其表达及相关信号通路可能为心脏疾病的诊断和防治提供新的可能性。但目前尚缺少对于BAG3在心脏疾病中的作用的系统阐述。该文综述了BAG3的基本结构和功能,以及相关调控机制,聚焦于BAG3在多种心脏疾病中的作用,以期为疾病的诊断和治疗提供相应的理论支持。

基于BagR-CNN检测模型的物联网网关安全加固方法

物联网(IoT)网关作为多种网络间异构数据传输与交换的关键节点近年来长期遭受大规模攻击,可靠性差,大规模流量处理延时大、抗攻击能力差等问题显著。而现有对物联网网关的可靠性研究主要集中在加密技术和可信认证机制方面,没有解决大规模攻击环境下物联网的可靠性及安全性问题。因此,本文提出了基于BagR-CNN检测模型的物联网网关安全加固方法,设计了可低功耗集成在物联网网关上并能够快速检测出大规模多步骤攻击的模型。首先,不同于传统的单一流量分类,本方法将相关流量聚合到一个包中,并利用基于信息熵相关性的特征增强算法提高检测准确率。其次,区别于传统的特征提取与约简方法,本文提出基于包内相似度的特征扩展方法,挖掘出隐藏的关联信息并能保证包内数据在噪声扰动下的不变性。最后,本文提出基于高斯混合模型(GMM)的特征压缩算法,将聚合包映射为一维向量并由此训练简单的卷积神经网络,以提高检测效率。实验结果表明,基于BagR-CNN检测模型在准确率、召回率和F1值等方面均优于目前对于大规模多步骤攻击的检测方法。同时,在模拟网关上运行时平均CPU利用率(不使用GPU)低于20%,证明该方法适合集成到网关而不影响网关正常的数据传输工作。

Effects of different color paper bags on aroma development of Kyoho grape berries

This study investigated the influence of red,green,blue,and white paper bags on the free volatile compound development of Kyoho grape berries from green to harvest.Seven functional groups of volatiles were identified during the development of Kyoho grape berries including esters,aldehydes,alcohols,terpenes,ketones,acids,and hydrocarbons.Esters and aldehydes were abundant in Kyoho grape berries,mainly represented by ethyl acetate,ethyl butyrate,and(E)-2-hexenal.They accumulated quickly after veraison and slightly decreased toward maturation.Red,green,blue,and white paper bags promoted the accumulation of esters and inhibited the accumulation of aldehydes,also inhibited the accumulation of alcohols,tepenes,ketones,and acids.Their effect from strong to weak was green,blue,red,and white paper bags.The expression profiles of genes in the lipoxygenase-hydroperoxide lyase(LOX-HPL) pathway were also analyzed and the results indicated that the regulation of red,green,blue,and white paper bags on aldehydes,alcohols,and esters volatile aromas was at transcriptional level.The results expanded our comprehension in grape aroma biosynthesis and berry bagging technique in table grape cultivation.

基于Bagging混合策略的多风电场稀疏向量自回归概率预测

风电功率预测对电力系统的安全稳定运行具有重要意义。针对多风电场的超短期概率预测问题,提出了一种基于Bagging混合策略和核密度估计(kernel density estimation,KDE)的稀疏向量自回归预测方法。首先通过时间序列分解和余项自举,生成若干自举时间序列。对于每个时间序列,采用向量自回归(vector autoregression,VAR)模型进行预测。针对传统模型在风场数量较多时容易出现的过拟合问题,采用稀疏向量自回归模型,筛选最有效的回归系数,得到稀疏系数矩阵。每个时间序列训练的预测模型分别产生点预测结果,对于多重点预测结果,使用KDE方法产生概率密度的预测结果。在真实风电集群数据上,验证所提多场站概率预测方法的有效性,采用分位数得分评估概率预测精度。相关实验结果表明,该方法可以有效提高概率预测精度。

基于Bagging-异质k近邻的输电电缆故障诊断方法

针对110 kV交叉互联电缆输电线路故障分类不全、分类准确率低等问题。提出了一种基于Bagging-异质k近邻提升学习的交叉互联电缆故障分类方法,首先通过对各类故障得到的主芯及护层电流、电压等相关电气参数归一化处理,构建电气参数特征矩阵;然后基于k近邻(k-NN)算法采用不同k值及不同距离度量作为个体学习器并构建高差子学习器,通过引入Bagging算法提高异质学习器的整体学习效率,可以实现针对不同类型、不同区域交叉互联输电电缆故障的有效区分。该方法相比于传统SVM、k-近邻及逻辑回归等分类方法,降低了多分类误差率及空间复杂度并提高了模型泛化能力,具有较大的工程运用潜力。

EffectS of sequence of nylon bags rumen incubation on kinetics of degradation in some commonly used feedstuffs in dairy rations

Nowadays, most available information on the degradative behaviour of feeds in ruminants is based on in situ incubation in the rumen, and it is adopted by many feed evaluation systems currently in use for ruminants. However, the outcome of.this technique might be affected by many factors such as sequence of nylon bags incubation in the rumen. The objective of current study was to investigate effects of sequence of nylon bag incubation on degradative behavior of dry matter （DM）, crude protein （CP）, neutral detergent fiber （NDF） and acid detergent fiber （ADF） in some feed ingredients commonly used in dairy rations, including alfalfa haylage, corn silage, corn grain and soybean meal. Four multiparous Holstein lactating cows fitted with permanent ruminal cannulas were used. The nylon bags containing feed samples either were placed in the rumen at once and removed at designated time intervals （all in-gradually out method; AG） or were placed in the rumen at designated time points and retrieved at once （gradually in-all out method; GA）. Fractional rate of degradation of potentially degradable fraction, lag time and effective rumen degradability （ED） of DM and CP were significantly higher in the AG compared to the GA method （P〈0.05）. Fractional rates of DM and CP degradation was higher in alfalfa haylage samples incubated in the rumen using the AG method compared to that using the GA method （0.138 h-1 vs. 0.073 h-1 and 0.002 h-1 vs. 0.1125 h-1, for DM and CP, respectively; P〈0.05）. Due to a higher fractional rate of degradation （Kd） of DM and CP, the ED of DM and CP at different fractional passage rates were higher in the AG than those in the GA method （P〈0.05）. Potentially degradable fraction and lag time of NDF were higher in the AG method compared to the GA method （P〈0.05）. Placing all bags in the rumen at once and removing them at designated time intervals compared with introduction of bags in reverse sequence and removing them all at once led to a lower undegradable fraction （U） of NDF in alfalfa （1.8% vs. 4.0%, respectively; P〈0.05） and corn silage （3.3% vs. 6.7%, respectively; P〈0.05） samples. Potentially degradable fraction of ADF was significantly higher in the AG method compared with the GA method （P〈0.05）. Bag incubation sequence had profound effects on kinetics of degradation of DM, CP and NDF in situ in the feed samples studied. The effects were more evident in the forages （especially alfalfa haylage） than in the concentrate ingredientsnamely corn grain and soybean meal..This experiment is the first time to investigate effects of two methods under the same experiment conditions, providing basic data for the determination of ED.

Packaging Bags of Peanuts with Function of Prevention of Aflatoxin B_1

Packaging bags composited with barrier film and moisture absorbent nonwoven fabrics were prepared in order to design a kind of functional bag which could prevent the contamination of aflatoxin B1of peanuts. The internal relative humidity( RH) of packaging bags with peanuts was monitored. The influences of the superabsorbent fiber( SAF) and jute fiber were investigated and the mechanism was analyzed.

Study of Durability of Siliceous Sand Based Mortars in Togo, and of Binder of Plastic Bags of the Kind “Voltic”: Hydrocarbons’ Effect

The present study aims at environmental protection through the use of plastic wastes in the production of mortar. The behavior of siliceous sand-based mortars from Togo and binders of plastic bags of the kind “voltic” is analyzed. Mortar samples from a mixture of siliceous sand and binder of plastic bags are prepared and subjected to physical and mechanical tests after immersion in the hydrocarbon from 0 hour to 504 hours. The result demonstrates that hydrocarbons have no influence on mechanical properties of mortars for an immersion time below 3 hours. Between 3 hours and 24 hours the presence of hydrocarbon increases their physical and mechanical properties. After 24 hours mortars generally lose the mechanical properties of around 8% to 24% due to the loss of viscosity and cohesiveness of the binder caused by the fuel. The behavior in the face of hydrocarbons shows that the material can be used in the surface of roads by carefully avoiding that hydrocarbons remain on the roads for a period of time beyond 24 hours.

Analysis of Heavy Metal Lead and Chromium Elements in Food Packaging Bags

[Objectives]This study was conducted to detect the contents of heavy metal lead and chromium in food packaging bags.[Methods]The contents of heavy metal lead and chromium in food packaging bags were determined by microwave digestion-flame atomic absorption spectrophotometer.With concentrated nitric acid and 30%hydrogen peroxide solution as the digestion system,food packaging bags of different materials,plastic packaging bags and paper packaging bags,were ultrasonically digested and then determined for the contents of heavy metal lead and chromium by flame atomic absorption spectrophotometry.[Results]The determination results showed that the linear correlation coefficient of lead was 0.9967,and the linear correlation coefficient of chromium was 0.9977.The method has the characteristics of simplicity,high analysis speed and high sensitivity.[Conclusions]This study provides a theoretical basis for the safety of food packaging bags.

联合自适应邻域和Bagging的协同表示集成学习方法

近年来,协同表示分类(collaborative representation classification,CRC)算法成为高光谱遥感影像分类的研究热点,其中基于bagging的协同表示集成学习算法(bagging-based collaborative representation classification,BagsCRC)利用bagging集成方式有效地提高了基分类器协同表示分类算法的精度。为进一步提升BagsCRC算法的有效性,文章提出了一种联合自适应形状邻域和bagging协同表示集成学习算法(shape-adaptive bagging-based collaborative representation classification,SABagsCRC)。该算法通过构建训练样本和测试样本的自适应形状邻域,进而构建空间信息约束的分类器集成模式。实验采用Indian pines和Washington DC Mall两组高光谱遥感影像,对所提出算法的性能进行了评价。实验结果表明,SABagsCRC算法在分类效果上比BagsCRC算法有明显的提升。

低银BAg10CuZnSnInNd钎料组织与性能

研究了复合添加微量In和Nd元素对低银BAg10CuZnSn钎料熔化特性、润湿性能、显微组织及钎焊接头力学性能的影响.结果表明,In元素的添加可以显著降低钎料的固、液相线温度,而Nd元素对钎料的固、液相线温度没有明显的影响.适量In元素和Nd元素的添加可以显著提高钎料在304不锈钢和紫铜上的铺展面积,同时钎料的显微组织得到了明显细化,过量添加In元素和Nd元素后钎料组织中出现了富铟相和稀土相.当In和Nd元素的添加量分别为2%和0.1%时,304不锈钢/304不锈钢接头的抗剪强度达到最大值430 MPa,而304不锈钢/紫铜的钎焊接头发生断裂,且均断于紫铜处,说明钎焊接头的强度大于紫铜.

Research Note: Bird-Resistant Pollination Bags for Sorghum Breeding and Germplasm Maintenance

Bird damage is a problem in sorghum breeding and germplasm maintenance operations. Paper pollination bags are damaged by rain and provide only a minimal deterrent to birds. To overcome these limitations we fabricated pollination bags from spun polyethylene fiber sheeting. No seed yield difference was found between plants bagged with either spun polyethylene or paper. Seed loss by bird damage was nearly eliminated under the polyethylene bags. In areas where bird damage is problematic bird resistant pollination bags can allow for a reduction in the plot size required for breeding and germplasm maintenance operations, increase the productivity of such operations as genetic diversity per unit land area, and make direct measurement of seed yield possible in agronomic field experiments.

The Microenvironment within and Pollen Transmission through Polyethylene Sorghum Pollination Bags

Bird damage is a problem in sorghum breeding and germplasm maintenance operations. Paper pollination bags are damaged by rain and provide minimal deterrent to birds. Earlier we reported upon bird resistance of spun polyethylene pollination bags. Herein, we report the potential for pollen transmission through, and the microenvironment within, hard form (HfT) and soft form (SfT) spun polyethylene pollination bags as compared to traditional Paper pollination bags. Within Paper pollination bags morning temperatures were 10°C - 15°C above ambient and high temperature excursions as high as 45°C were measured. Heating in Sft and HfT was 25% and 50% that of Paper, respectively. Temperature differences between bags were attributed to differences in albedo and air permeability of the bag materials. No difference in pollen transmission through Paper and HfT was found. Although SfT allowed 35% - 40% wind borne pollen through the pores as compared to controls, male sterile plants covered with SfT produced only 30 seeds/panicle, about 1% of a self-pollinating fertile plant. Our results suggested that SfT could adequately reduce or eliminate cross-pollination in self-pollinating plants while maintaining near ambient environmental conditions.

Packaging Bags with the Function of Micro-environment Modification

Three kinds of packaging bags composited with barrier film and moisture absorbents were designed in order to find out how to create an internal micro-environment with low O2content and relative humidity( RH). Peanuts with different moisture contents were filled into packaging bags and stored in an environmental chamber for a certain period of time. An RH recorder was sealed in each bag and the RH inside the bag was recorded. The moisture contents of peanuts before and after storage were measured as well.It is found that peanuts with moisture content of 13% can reduce O2content inside the bag by the aerobic respiration,achieving the self modified atmosphere packaging( MAP) effect. A microenvironment with lower RH can be created by using super-absorbent fiber( SAF) or mineral bag as the moisture absorbent. The moisture contents of peanuts stored in the bags with SAF and mineral bag as moisture absorbent decreased from 13% to 10. 5%and 11. 3%,respectively. SAF is a promising material of packaging bags composited with barrier film,in which a low RH and high CO2content can be created.

The Validity of the Reduction of Disposable Plastic Checkout Bags in Japan

This study examined the effect of reducing disposable plastic checkout bags used in supermarkets, convenience stores, and so on in Japan. Considering that even when these checkout bags are abolished, alternative waste bags should be newly produced, because these checkout bags have been reused as household waste bags so far, and the corresponding amount of oil is still necessary to produce them, the amount of oil saved by this bag reduction was found to be 0.2 L/person/year at most. Further, it was demonstrated that the necessity to purchase substitute bags may increase the household and financial burden on consumers.