Support vector regression for determining the minimum zone sphericity

Several methods have been investigated to determine the deviation of manufactured spherical parts from ideal geometry. One of the most popular is the least squares technique, which is still widely employed in coordinate measuring machines used by industries. The least squares algorithm is optimal under the assumption that the data set is very large and has the inherent disadvantage of overestimating the minimum tolerance zone, resulting sometimes in the rejection of good parts. In addition, it requires that the data be distributed normally. The support vector regression approach alleviates the necessity for these assumptions. While most fitting algorithms in practice today require that the sampled data accurately represent the surface being inspected, support vector regression provides a generalization over the surface. We describe how the concepts of support vector regression can be applied to the determination of tolerance zones of nonlinear surfaces; to demonstrate the unique potential of support vector machine algorithms in the area of coordinate metrology. In specific, we address part quality inspection of spherical geometries.     

Structure–Property Relationships in Aligned Electrospun Barium Titanate Nanofibers

Barium titanate nanofibers were uniaxially aligned by electrospinning onto a rotating copper wire drum and alignment was maintained during calcination of the fibers. Two methods for maintaining alignment during calcination were tested, by either using carbon tape or a peeling off method to remove the aligned fibers from the mandrel followed by calcination. The carbon tape removal method led to the formation of shorter aligned nanowires while the peeling off method resulted in longer nanofibers. Additionally, the effects of calcination temperature and time on crystal structure were also examined. The degree of tetragonality in the barium titanate nanofibers increased at higher calcination temperatures and times. Piezoelectricity was confirmed in the nanofibers calcined using piezoeresponse force microscopy, yielding a d₃₃ value of 15.5 pm/V. Using the methods presented here, large quantities of aligned piezoelectric barium titanate and other ceramic fibers or wires can be produced to fulfill their demand in novel microelectronics.     

Increasing the hydrophobic interaction between terminal W-motifs enhances the stability of Salmonella typhimurium sialidase. A general strategy for the stabilization of {beta}-propeller protein fold

Protein engineering of the ß-propeller protein aimedat enhancing the structural stability of the protein was carriedout using a monomeric single domain ß-propeller protein,Salmonella typhimurium sialidase, as a model. Ala53 and Ala69each located at strands B and C of the W1 motif were mutatedto Leu and Val, respectively, to increase the hydrophobic interactionbetween W1 and W6 motifs. The mutants showed enhanced stabilitytowards guanidine hydrochloride and thermal unfolding. Ala53Leushowed higher stability, probably owing to the capability ofthe mutated Leu to interact extensively with more residues involvedin the hydrophobic interactions between the terminal W-motifs.The mutations, which are located far from the active site, haveno significant effect on the enzymatic properties. The strategyto enhance the stability proposed here might be applied to theother ß-propeller proteins.     

Exaggerated capacitance using electrochemically active nickel foam as current collector in electrochemical measurement

In the past decades, nickel and cobalt oxide/hydroxide materials have been investigated intensively for supercapacitor applications. Some works report very high specific capacitance values, up to 3152 F g⁻¹, for these materials. By contrast, some other works report quite modest capacitance values, up to 380 F g⁻¹ for the same materials prepared using same strategy. It is found that most works reporting very high capacitance value applied nickel foam as current collector. In this paper, surface chemistry and electrochemical properties of nickel foam are investigated by XPS analysis, cyclic voltammetry and galvanostatic charge-discharge measurement. The results show that using nickel foam as current collector can bring about substantial errors to the specific capacitance values of electrode materials, especially when small amount of electrode active material is used in the measurement. It is suggested that an electrochemically inert current collector such as Ti or Pt film should be used for testing electrochemical properties of nickel and cobalt oxide/hydroxide positive electrode materials.     

Learning networks for tornado detection

In this paper, different types of learning networks, such as artificial neural networks (ANNs), Bayesian neural networks (BNNs), support vector machines (SVMs) and minimax probability machines (MPMs) are applied for tornado detection. The last two approaches utilize kernel methods to address non-linearity of the data in the input space. All methods are applied to detect when tornadoes occur, using variables based on radar derived velocity data and month number. Computational results indicate that BNNs are more accurate for tornado detection over a suite of forecast evaluation indices.     

Optimisation of conditions for the degradation of mimosine in Leucaena leucocephala leaf

A study was made of the rate of degradation of mimosine to 3-hydroxy-4(1H)-pyridone in harvested leucaena leaf under various conditions. Optimum rates of degradation of an aqueous leucaena slurry were at pH 8.0 and 45°C with virtual total loss of mimosine in 10 min. Heating the intact leaf also reduced the mimosine content with the maximum rate of degradation at 70°C. The results have implications for reducing the toxicity of leucaena used for stock feed.     

Anthocyanin composition of the red wine Babić affected by maceration treatment

Identification of anthocyanins in the wine made of the Croatian autochthonous grape variety of Babić (Vitis vinifera L.) was carried out and their profile was determined by means of high-performance liquid chromatography with diode array and mass spectrometric detection. Dependence of anthocyanins content and profile on maceration treatment conditions was investigated. Statistically significant differences of anthocyanins concentration in wines Babić produced by various maceration treatments were confirmed by the use of multivariate analysis of variances. The investigation results indicated that the maceration temperature exerts higher influence on anthocyanins concentration than the duration of maceration. In addition, on the basis of anthocyanin composition and using different multivariate statistical analyses, differentiation of wines Babić according to maceration treatments was procured.     

火灾中无约束钢梁的扭转弯曲的设计方法

采用数字分析和相关试验结果研究了无约束钢I截面梁的行为,采用有限元程序拓展了数学模型。在相同弯矩和中跨集中荷载的情况下,对一系列不同的UB和UC截面以及不同跨度,进行了研究。比较了预估的弯矩值与相关试验结果。在此基础上,对无约束梁提出了一种新的更精确和安全防火预报的方法,该方法克服了欧洲规范（EC3：1．2）设计公式中的一些弱点。另外,给设计者提供了一个便捷和简单的设计方法,即该方法易懂又合理,称为兰金方法。可用于预估钢梁在火中的LTB破坏荷载。兰金方法为数值预估提供了一个适宜的下界值。     

Proposed design methods for lateral torsional buckling of unrestrained steel beams in fire

The behaviour of unrestrained steel I-beams has been studied by means of numerical analysis and published experimental results. The numerical model was developed using a commercial finite element program, MSC.MARC Mentat. A series of different UB and UC sections and different spans, subjected to both uniform moment and midspan point loads, are considered. The numerical predictions of the buckling moments are then compared with published experimental results. Consequently, a new approach is proposed to provide more accurate and safe predictions of the fire resistance of unrestrained beams, as well as to overcome certain weaknesses in the EC3:1.2 [European committee for standardization (CEN). Eurocode 3: Design of steel structures, Part 1.2: General rules — structural fire design, EN 1993-1-2. Brussels (Belgium); 2005] design formula. In addition, to provide a quick and simple design approach for engineers, a straightforward and rational method known as the Rankine method is introduced to predict the LTB failure load of steel beams in fire. It is shown that the Rankine approach generally provides a good lower bound value for numerical predictions.