摘要：目的:建立一种较为快速和快速确定非均匀岩土材料渗透系数的方法。创新点:建立了一种可以从图像到数值模型的数字图像方法:通过拍照、CT等手段获取岩土材料的图像,进而通过数值分析确定等效参数。方法:1.将采集到彩色图像从RGB空间转化到HSI空间,选取识别度较高的空间进行二值化处理;2.获取二值化图像后采用邻域标记算法标记,结合本文提出的算法提取边界(图9和10);3.结合边界修正算法对锯齿状边界进行修正(图11);4.确定表征细观几何模型(图12和表1);5.绘制网格开展数值分析,确定宏观参数。结论:1.基于数值图像的非均匀岩土材料渗透系数确定方法可以较为准确地估算渗透系数,可以为工程设计提供初步依据。2.非均匀岩土材料具有明显的尺寸效应,随着尺寸增加,渗透率的变化逐渐趋于稳定;当材料视为岩石和土体的二元介质时,两种性质差异在10倍以内对宏观特性的影响较大,大于10倍之后影响减弱。3.岩土材料渗透率随着内部块石含量的增加而减小,但是内部块石的形态对渗透率也有一定的影响。

摘要：随着云计算的飞速发展,数据中心能耗问题日益突出,亟须探索更加智能高效的节能优化新方法。文章分析了数据中心的能耗问题,阐述了强化学习技术在数据中心能耗调度中的应用潜力,构建了一个涵盖服务器、制冷等关键设施的数据中心系统模型并基于该模型搭建了一个精细化的数据中心能耗评估框架,将调度问题形式化为一个马尔可夫决策过程,设计了一种融合图神经网络与长短期记忆网络的深度强化学习算法,最后搭建了仿真平台验证所提出策略的有效性。

摘要：采用改进型Hammerstein动态非线性模型来设计数字预失真器,用于矫正Doherty射频功放的动态非线性,从而获得一个适合于诸如WCDMA、CDMA2000和WiMAX这样的新型宽带无线通信系统的高效线性射频功率放大系统。文中使用频率间隔5MHz的两载波3GPP-FDD WCDMA信号作为测试信号,设计了一个16W峰值输出功率的L波段Doherty射频功率放大器。实验表明基于改进型Hammerstein动态非线性模型的数字预失真器可以很好地抑制Doherty射频功放的动态非线性引起的频谱再生,从而有效地降低了邻道干扰。

摘要：为提高智能汽车的路径跟踪能力,并保证其在极限工况下的动力学稳定性,以四轮驱动智能电动汽车为研究对象,根据转向和主动横摆力矩(Direct yaw moment,DYC)系统的特点分别设计控制律进行协调控制。首先,针对汽车在转向过程中轮胎侧偏刚度的不确定性,利用线性矩阵不等式(Linear matrix inequality,LMI)理论构造可实现系统区域极点配置的鲁棒控制器,并研究其求解方案。然后,采用分层架构设计主动横摆力矩的控制律;其中,上层控制器通过车-路运动学关系,基于线性时变模型预测控制(Linear-time-varying model predictive control,LTV-MPC)计算期望横摆角速度;下层采用基于双曲正切趋近函数的滑模控制计算主动横摆力矩,为了在提高跟踪精度的同时确保汽车动力学稳定性,在滑模面中引入质心侧偏角的控制权重,其大小根据质心侧偏角稳定性相图确定。考虑到在大多数常见工况中,转向系统单独作用就已经可以取得良好的控制效果,对主动横摆力矩系统设置激活机制,使其仅在转向系统被判定难以完成当前控制目标时才介入,避免了正常工况下的非必要激活引起的耗能。最后,通过Simulink-CarSim联合仿真进行了算法验证,结果表明,即使在较极端的工况下,所提出的控制方法仍然能保持良好的循迹控制效果,并且可以很好地确保汽车的动力学稳定性。

摘要：为了研究苹果汁生产中棒曲霉素产生菌的快速检测,利用实时PCR方法快速检测扩展青霉的可能性,对扩增条件进行优化。在polygatacturonase基因引物设计和传统PCR扩增扩展青霉DnA的基础上,研究实时PCR扩增时退火温度、引物浓度以及底物质量浓度对扩增效果的影响,以获得最佳的参数。结果表明,用Lightercy-cler实时PCR扩增扩展青霉DnA的最佳退火温度为61℃,最佳引物浓度为0.20-0.40μmol/L,底物质量浓度对实时PCR扩增的影响较小。在以上参数下,可以获得良好的PCR扩增曲线、产物溶解曲线以及清晰的产物条带。研究获得的快速检测扩展青霉的实时PCR参数,可用于浓缩苹果汁工业化生产中扩展青霉的快速检测,也可作为其他微生物实时PCR检测时的方法学参考。

摘要：Organ-on-a-chip systems have been increasingly recognized as attractive platforms to assess toxicity and to develop new therapeutic ***,current organ-on-a-chip platforms are limited by a“single pot”design,which inevitably requires holistic analysis and limits parallel ***,we developed a digital organ-on-a-chip by combining a microwell array with cellular microspheres,which significantly increased the parallelism over traditional organ-on-a-chip for drug *** to 127 uniform liver cancer microspheres in this digital organ-on-a-chip format served as individual analytical units,allowing for analysis with high consistency and quick *** platform displayed evident anti-cancer efficacy at a concentration of 10μM for sorafenib,and had greater alignment than the“single pot”organ-on-a-chip with a previous in vivo *** addition,this digital organ-on-a-chip demonstrated the treatment efficacy of natural killer cell-derived extracellular vesicles for liver cancer at 50μg/*** successful development of this digital organ-on-a-chip platform provides high-parallelism and a low-variability analytical tool for toxicity assessment and the exploration of new anticancer modalities,thereby accelerating the joint endeavor to combat cancer.

摘要：The study and characterization of biomolecules involved in the interaction between mycobacteria and their hosts are crucial to determine their roles in the invasion process and provide basic knowledge about the biology and pathogenesis of *** new biomarkers for diagnosis and immunotherapy have emerged *** is an ancient pathogen that has developed complex strategies for its persistence in the host and environment,likely based on the complexity of the network of interactions between the molecules involved in *** biomarkers have received recent attention in the process of developing rapid and reliable detection techniques for *** the most widely investigated antigens are CFP-10(10-kDa culture filtrate protein),ESAT-6(6-kD a early secretory antigenic target),Ag85 A,Ag85 B,CFP-7,and *** of these antigens have been proposed as biomarkers to assess the key elements of the response to infection of both the pathogen and *** design of novel and accurate diagnostic methods is essential for the control of tuberculosis ***,the diagnostic methods are based on the identification of molecules in the humoral response in infected ***,these tests depend on the capacity of the host to develop an immune response,which usually is *** the last 20 years,special attention has been given to the design of multiantigenic diagnostic methods to improve the levels of sensitivity and *** this review,we summarize the state of the art in the study and use of mycobacterium biomolecules with the potential to support novel tuberculosis control strategies.

摘要：A technique for compensation of temperature effects in fiber grating sensors is reported. For strain sensors and other sensors related to strain such as electromagnetic sensors, a novel structure is designed, which uses two fiber Bragg gratings (FBGs) as strain differential sensor and has temperature effects cancelled. Using this technique, the stress sensitivity has been amplified and gets up to 0.226 nm/n, the total variation in wavelength difference within the range of 3-45 °C is 0.03 nm, 1/14 of the uncompensated FBG. The structure can be used in the temperature-insensitive static strain measurement and minor-vibration measurement.

摘要：2-图是边的尺寸至多为2的超图,极小正则2-图是不含有真正则因子 的正则2-图．设．f2(n)为所有n个顶点的极小正则2-图的最大度数．给出了极 小正则2-图的一个结构性质,并由此证得f2(n)=(n+3-i)／3,其中1≤i≤6, n≥7,i≡n(mod 6),从而解决了范红兵等人提出的一个猜想．作为在图论中的 应用,可以刻画不可分解因子的正则图,并给出关于度条件的最好可能的因子 存在性定理．进而,f2(n)和极小2-图可应用于最初引发这项研究的通用开关盒 设计问题．

摘要：目的:建筑物的材质信息是灾害评估和城市调查等领域的重要信息。本文旨在利用高光谱遥感影像提取地面建筑物的表面材质信息(包括材质类型和主要组成成份),并对提取方法进行对比,给出应用建议。创新点:对建筑物材料进行光谱测试,并对其高光谱响应规律进行分析,找出有诊断意义的光谱位置;基于实验和验证得出应用方法的适应性,以提高信息提取精度。方法:1.设计建筑物材质信息提取流程(图1),并对高光谱数据进行基础处理;2.对建筑物材料进行光谱测试(波长范围为350~2500 nm,图3),并完成各类建筑物的诊断性光谱分析;3.利用光谱角度法(公式(1))和光谱信息散度法(公式(2))进行材质信息提取(图5和6);4.综合分析两种方法的应用过程与控制参数和准确率的关系。结论:1.两种方法皆可提取建筑物材质信息,但在应用过程中需要进行参数的适应性调整,这是提高准确率的关键;2.在建筑物材质信息提取方面,光谱角度法的提取准确率略高于光谱散度法。