Responses of the reflectance indices PRI and NDVI to experimental warming and drought in European shrublands along a north-south climatic gradient

The aim of this study was to evaluate the use of ground-based canopy reflectance measurements to detect changes in physiology and structure of vegetation in response to experimental warming and drought treatment at six European shrublands located along a North-South climatic gradient. We measured canopy reflectance, effective green leaf area index (green LAIe) and chlorophyll fluorescence of dominant species. The treatment effects on green LAIe varied among sites. We calculated three reflectance indices: photochemical reflectance index PRI [531 nm; 570 nm], normalized difference vegetation index NDVI₆₈₀ [780 nm; 680 nm] using red spectral region, and NDVI₅₇₀ [780 nm; 570 nm] using the same green spectral region as PRI. All three reflectance indices were significantly related to green LAIe and were able to detect changes in shrubland vegetation among treatments. In general warming treatment increased PRI and drought treatment reduced NDVI values. The significant treatment effect on photochemical efficiency of plants detected with PRI could not be detected by fluorescence measurements. However, we found canopy level measured PRI to be very sensitive to soil reflectance properties especially in vegetation areas with low green LAIe. As both soil reflectance and LAI varied between northern and southern sites it is problematic to draw universal conclusions of climate-derived changes in all vegetation types based merely on PRI measurements. We propose that canopy level PRI measurements can be more useful in areas of dense vegetation and dark soils.     

扩散/氧化工艺控制管理系统的研制

本文给出一种半导体扩散/氧化生产工艺控制管理系统。系统由下位工艺控制单元和上位管理计算机组成。下位工艺控制单元实现扩散/氧化工艺要求的温度、气体流量控制及推拉舟位置控制。上位管理计算机实现扩散/氧化工艺管理、分析、与下位工艺控制单元互传信息。     

小兴安岭7种松叶挥发油GC-MS数据的分析

用化学计量学方法分析小兴安岭7种松科植物松叶挥发油气相色谱-质谱(GC-MS)数据,为松叶挥发油的药理活性与其它的应用研究提供依据。(1)用直观推导式演进特征投影(heuristic evolving latent projections,HELP)法分辨重叠色谱峰,得各组分的纯色谱峰和质谱;(2)用正交投影法比较不同挥发油的GC-MS数据;(3)用峰面积归一化法确定各化合物的相对含量;(4)用主要化学成分进行聚类分析。7种松叶挥发油的化学成分为单萜、倍半萜及其衍生物和酯类化合物,按化学成分7种松叶挥发油可分为3类。     

最坏情况下#3-SAT问题最小上界

最坏情况下#SAT问题上界的研究已成为一个热门的研究领域.#SAT问题的时间复杂性是根据问题实例的大小所组成的函数计算所得.#SAT问题实例的大小不仅依赖于变量的数量,还依赖于子句的数量.以子句数量为参数研究#SAT问题在最坏情况下的上界,不仅可以从另一个角度衡量算法的好坏,而且在某种程度上更能准确地反映出算法的性能.首先从子句数量的角度证明了之前提出的基于扩展规则的模型计数算法(CER算法)的上界O(2m),其中m是公式中子句的数量.为了提高#3-SAT问题的求解效率,采用了多种分裂规则,进一步给出了一种基于Davis-Putnam-Logemann-Loveland(DPLL)的#3-SAT算法MCDP.通过分析该算法得到了以子句数量为参数的#3-SAT问题在最坏情况下的上界O(1.8393m).     

一种最大向量平均个数的估计方法

提出一种估计n个d维向量中最大向量平均个数的方法。该方法通过分析单个向量与其他向量子集的支配关系,求出最大向量平均个数的解析式。证明解析式满足已知的递归关系,得到最大向量平均个数的近似估计。与已有方法相比,该方法可应用到估计k个其他向量支配的平均个数问题。     

Least trace extended set-membership filter

To improve the consistency of estimation result, a least-trace extended set-membership filter (LTESMF) is presented for a class of nonlinear stochastic systems, which has linear output and unknown- but-bounded noise. Feedback technique is used instead of the intersection of ellipsoid-sets in the measurement update. The feedback parameter is optimized in order to minimize the trace of error bounded ellipsoid’s envelop matrix. A new stability analysis method was developed to prove the stochastic system’s stab...     

基于LabVIEW的电磁波峰焊非接触液位测量系统

在电磁波峰焊接过程中,液位波动大小是一个非常重要的参数,如果锡液液位波动大,易造成虚焊等问题,对电磁波峰焊液位波动的实时监控显得尤为重要.通过使用液位测量模块、Arduino控制器及计算机组成的非接触液位测量系统对电磁波峰焊的锡液液位波动进行测量,结合虚拟仪器软件LabVlEW将液位波动数值和液位波动曲线可以形象地显示出来,同时对液位波动范围进行预先设置,当超出液位波动设置的最大值或者低于液位波动设置的最小值就会给出警报并及时反馈,从而提高焊接质量.通过实验测量与验证,实验测量的液位波动程度与预期值相符合,且很平稳.     

Development of ‘UR-System 2’: a training system for recovery of motor function of plegic upper limb after stroke

We developed a new training system, called ‘UR-System 2’, for the recovery of motor function of a plegic upper limb after stroke. UR-System 2, which was redesigned based on knowledge gained from clinical tests using UR-System 1, was newly equipped with a function for testing the motor function of patients, such as isolated movement. In order to verify the effectiveness of UR-System 2, we conducted the following procedures: we verified the safety of training in healthy persons; we gathered standard data on pronation and supination of healthy forearms during tests; and, we verified that the test function was effective in evaluating the recovery effect of isolated movement in two hemiplegic patients.     

肢体协调运动康复机器人的机构设计与实验

针对临床上缺少一种肢体协调运动康复训练设备的现状,研制了一款适用于偏瘫患者个性化训练的上下肢协调运动康复机器人.首先,在探究正常步态上下肢协调运动规律的基础上,选择以肩、膝关节角度协调变化规律作为机器人的设计目标;然后,基于五杆变胞机构设计了康复训练机构及主/辅传动链,并对训练机构进行了运动学分析;最后,在样机上进行了实验,结果表明该机器人能够满足设计目标.     

Output feedback regulation of upper triangular nonlinear systems with uncertain time‐varying delays in states and input

In this paper, an output feedback controller is studied to regulate a class of upper triangular nonlinear systems with uncertain time‐varying delays. The key features of our considered system are that there are uncertain time‐varying delays in both states and input and the high‐order nonlinearity is in a more relaxed form over the previous results. Theoretical analysis and numerical example are presented to show the benefits of our controller. Copyright © 2017 John Wiley & Sons, Ltd.