数据中心内服务器能耗数据采集及特征分析

数据中心的高能耗低能效问题正受到广泛关注与研究，但目前没有公开的数据中心内服务器能耗数据集供研究人员使用，且现有过滤式特征选择并不能满足运维人员的需求。为此，提出了一套模拟数据中心内服务器运行状态的仿真环境架构，基于该架构采集了服务器运行各类任务时的多项性能指标和能耗数据。然后将基于因果关系的特征选择应用于能耗数据集的特征分析中，构建出可解释的特征子集和能耗预测结果。实验结果表明，因果特征子集大小约为过滤式特征子集大小的1/3到1/6，并且使用因果特征子集训练的模型在75%的情况下都取得了最优预测精度。     

Antioxidant potential of extracts from peels and stems of yellow-fleshed and white cassava varieties

This study focused on the exploration of the potentials of extracting antioxidants from peels and stems of yellow-fleshed and white cassava varieties. The effect of particle size (0.2 and 0.5 mm) and variety on the phenolic content and antioxidant activity was assessed. The peels of the yellow-fleshed cassava variety with a particle size of 0.2 mm showed the highest phenolic content with 681.5 GAE mg 100 g⁻¹ and antioxidant activity of 19% and 425 μM TE g⁻¹ dry matter using DPPH and FRAP assays respectively. The stems of the white cassava with a particle size of 0.2 mm exhibited high phenolic content (442.4 GAE mg 100 g⁻¹) and antioxidant activity of 12.8% and 234 μM TE g⁻¹, better than the stem of the yellow-fleshed cassava. These results indicate that phenolic and antioxidant extractions were influenced by variety, the plant parts and particle size for the antioxidant assays.     

Hydrodistillation condition adjustment for different material particle sizes: a method to increase batch‐to‐batch quality consistency

Varying material particle sizes represent a common contributing factor to the batch‐to‐batch variation of extraction yields. To increase the batch‐to‐batch quality consistency of extracts, a method was proposed to adjust the extraction conditions for different material particle sizes, taking the hydrodistillation extraction process of Radix Curcumae and Fructus Gardeniae as a case study. Statistical models were built for five sesquiterpenes including curcumenone, curcumenol, curdione, curzerenone and furanodienone, to quantitatively describe the effects of particle size and process parameters on their extraction yields. An increase in sodium chloride concentration remarkably increased the yields of curcumenone and curcumenol, and a larger solvent‐to‐solid ratio increased the yields of five sesquiterpenes. Under the adjusted process parameters for two different particle sizes, the yield for each compound was controlled to fall in the 90–110% target range. The proposed method can be applied to various extraction processes of foods and herbal medicines.     

Feature selection and classification using support vector machine and decision tree

Breast cancer is one of the human threats which cause morbidity and mortality worldwide. The death rate can be reduced by advanced diagnosis. The objective of this article is to select the reduced number of features the help in diagnosing breast cancer in Wisconsin Diagnostic Breast Cancer (WDBC). This proposed model depicts women who all have no cancer cells or in benign stage later develop into malignant (metastases). Due to the dynamic nature of the big data framework, the proposed method ensures high confidence and low execution time. Moreover, healthcare information growth chases an exponential pattern, and current database systems cannot adequately manage the massive amount of data. So, it is requisite to adopt the “big data” solution for healthcare information.     

2-Acetyl-1-pyrroline: A key aroma component of aromatic rice and other food products

2-Acetyl-1-pyrroline is an aroma compound that gives aromatic rice its characteristic flavor. This compound either is present naturally in various food sources or is generated during certain processing methods, as reported in a number of studies. This review focuses on several sources of 2-acetyl-1-pyrroline, including aromatic rice, and the factors, including chemical and genetic parameters, affecting the formation of 2-acetyl-1-pyrroline. Extensive work has been conducted on the agricultural parameters, postharvest processing, storage, and cooking methods, influencing the concentrations of 2-acetyl-1-pyrroline in different food commodities. This article is an attempt to emphasize the importance of this compound in the food industry as a major aroma compound.     

综合改进奇异谱分解和奇异值分解的齿轮故障特征提取方法

针对齿轮故障特征微弱，在强背景噪声下难以有效提取的问题，提出了一种改进奇异谱分解（ISSD）结合奇异值分解（SVD）的齿轮故障特征提取方法。针对奇异谱分解（SSD）算法中模态参数需凭经验选取的缺陷，基于散布熵优化算法对SSD算法进行了改进，在得到既定的一组奇异谱分量的基础上，根据峭度值最大准则筛选出了最佳奇异谱分量并进行了SVD处理，采用奇异值能量标准谱自适应地确定了信号重构阶数以还原信号和提高降噪效果。最后对信号进行包络解调以提取齿轮故障特征，将所提方法运用到仿真信号和齿轮实测信号中，并同传统包络谱、SSD包络谱以及经验模态分解结合SVD(EMD-SVD)方法进行了对比分析，结果表明，所提方法的降噪和特征提取效果更佳，能够更加有效地实现齿轮故障的判别。     

Novel CPG algorithm for tracking fast sudden changes based on tangent rule

ABSTRACT

This paper proposes a novel tracking method to deal with fast changes of solar irradiation and power limit change in order to increase tracking efficiency. This goal is achieved by estimating (i) next operating mode and (ii) next step point with the use of tangent rule in triangle. After every fast response to sudden changes, accurate response phase starts in order to track desired power in each operating mode by adaptive step size. Drift problem in defining next operating mode is eliminated in proposed method by estimating next operating mode, and settling time is decreased to about 25 percent of settling time of other methods by estimating next step point. Simulation and experimental results show the performance of proposed method.     

Determination of four priority polycyclic aromatic hydrocarbons (4PAHs) by GC-MS in traditional Turkish yoghurts

ABSTRACT

Polycyclic aromatic hydrocarbons (PAHs) are ingested with foods and cause toxicities for humans. Yoghurt is one of the main foods that mediate PAH ingestion. Yan?k yoghurt, a traditional strained yoghurt, can contain PAHs due to its production process. Therefore, the concentration and types of four polycyclic aromatic hydrocarbons were determined by gas chromatography-mass spectrometry (GC-MS). Yan?k yoghurt samples were collected from different shops in Denizli, Turkey. For the method validation, the Eurachem guide (second edition) was adopted. Accordingly, linearity, working range, limits of detection (LOD), quantification (LOQ), precision and trueness values were set. Due to the selected validation parameters, the limit for detection was between 0.03 ng g^?1and 0.05 ng g^?1while the limit for quantification was between 0.10 ng g^?1 and 0.16 ng g^?1. Recovery rates higher than 83.80 % were obtained for four PAHs at two spiked concentrations (2.0 and 5.0 ng g^?1). Five Yan?k yoghurt samples and one commercial concentrated yoghurt sample were successfully analysed using the validated method.     

基于线特征及迭代最近点算法的地基建筑物点云自动配准方法

为克服迭代最近点(ICP)算法易陷入局部最优的缺陷，提出一种基于线特征及ICP算法的地基建筑物点云自动配准方法。首先，基于法向一致性进行建筑物点云平面分割；接着，采用alpha-shape算法进行点簇轮廓线提取，并拆分和拟合处理得到特征线段；然后，以线对作为配准基元，以线对夹角和距离作为相似性测度进行同名特征匹配，实现建筑物点云的粗配准；最后，以粗配准结果为初值，进一步采用ICP算法完成点云精确配准。利用两组部分重叠的建筑物点云进行配准实验，实验结果表明，采用由粗到精的配准方法能有效改善ICP算法对初值依赖的问题，实现具有部分重叠的建筑物点云的有效配准。