Apply Woods Model in the Predictions of Ambient Air Particles and Metallic Elements (Mn, Fe, Zn, Cr, and Cu) at Industrial, Suburban/Coastal, and Residential Sampling Sites

The main purpose for this study was to monitor ambient air particles and metallic elements (Mn, Fe, Zn, Cr, and Cu) in total suspended particulates (TSPs) concentration, dry deposition at three characteristic sampling sites of central Taiwan. Additionally, the calculated/measured dry deposition flux ratios of ambient air particles and metallic elements were calculated with Woods models at these three characteristic sampling sites during years of 2009-2010. As for ambient air particles, the results indicated that the Woods model generated the most accurate dry deposition prediction results when particle size was 18 μm in this study. The results also indicated that the Woods model exhibited better dry deposition prediction performance when the particle size was greater than 10 μm for the ambient air metallic elements in this study. Finally, as for Quan-xing sampling site, the main sources were many industrial factories under process around these regions and were severely polluted areas. In addition, the highest average dry deposition for Mn, Fe, Zn, and Cu species occurred at Bei-shi sampling site, and the main sources were the nearby science park, fossil fuel combustion, and Taichung thermal power plant (TTPP). Additionally, as for He-mei sampling site, the main sources were subjected to traffic mobile emissions

Analysis of some mixed elements for the Stokes problem

AbstractIn this paper we discuss some mixed finite element methods related to the reduced integration penalty method for solving the Stokes problem. We prove optimal order error estimates for bilinear-constant and biquadratic-bilinear velocity-pressure finite element solutions. The result for the biquadratic-bilinear element is new, while that for the bilinear-constant element improves the convergence analysis of Johnson and Pitkäranta (1982). In the degenerate case when the penalty parameter is set to be zero, our results reduce to some related known results proved in by Brezzi and Fortin (1991) for the bilinear-constant element, and Bercovier and Pironneau (1979) for the biquadratic-bilinear element. Our theoretical results are consistent with the numerical results reported by Carey and Krishnan (1982) and Oden et al. (1982)

Cost-Sensitive Learning for Recurrence Prediction of Breast Cancer

Breast cancer is one of the top cancer-death causes and specifically accounts for 10.4% of all cancer incidences among women. The prediction of breast cancer recurrence has been a challenging research problem for many researchers. Data mining techniques have recently received considerable attention, especially when used for the construction of prognosis models from survival data. However, existing data mining techniques may not be effective to handle censored data. Censored instances are often discarded when applying classification techniques to prognosis. In this paper, we propose a cost-sensitive learning approach to involve the censored data in prognostic assessment with better recurrence prediction capability. The proposed approach employs an outcome inference mechanism to infer the possible probabilistic outcome of each censored instance and adopt the cost-proportionate rejection sampling and a committee machine strategy to take into account these instances with probabilistic outcomes during the classification model learning process. We empirically evaluate the effectiveness of our proposed approach for breast cancer recurrence prediction and include a censored-data-discarding method (i.e., building the recurrence prediction model by only using uncensored data) and the Kaplan-Meier method (a common prognosis method) as performance benchmarks. Overall, our evaluation results suggest that the proposed approach outperforms its benchmark techniques, measured by precision, recall and F1 score

Using the Taguchi Method and Finite Element Method to Analyze a Robust New Design for Titanium Alloy Prick Hole Extrusion

AbstractIn the process of prick hole extrusion, many factors must be controlled to obtain the required plastic strain and desired tolerance values. The major factors include lubricant, extrusion speed, billet temperature, and die angle. In this paper, we employed rigid-plastic finite element (FE) DEFORMTM software, to investigate the plastic deformation behavior of a titanium alloy (Ti-6Al-4V) billet as it was extruded through a conical prick hole die. We systematically examined the influence of the semi-cone angle on the prick hole die, the diameter of prick hole die, the factor of friction, the velocity of the ram and the temperature of the billet, under various extrusion conditions. We analyzed the strain, stress and damage factor distribution in the extrusion process. We used the Taguchi method to determine optimum design parameters, and our results confirmed the suitability of the proposed design, which enabled a prick hole die to achieve perfect extrusion during finite element testing

Exclusive B→(K∗,ρ)γB \to (K^*, \rho) \gamma decays in the general two-Higgs-doublet models

By employing the QCD factorization approach, we calculated the next-to-leading order new physics contributions to the branching ratios, CP asymmetries, isospin and U-spin symmetry breaking of the exclusive decays $B \to V \gamma$ ($V=K^*, \rho$), induced by the charged Higgs penguins in the general two-Higgs-doublet models. Within the considered parameter space, we found that (a) the new physics corrections to the observables are generally small in the model I and model III-A, moderate in model II, but large in model III-B; (b) from the well measured branching ratios and upper limits, a lower bound of \mhp > 200 GeV in model II was obtained, while the allowed range of \mhp in model III-B is 226 \leq \mhp \leq 293 GeV; these bounds are comparable with those from the inclusive $B \to X_s \gamma$ decay; (c)the NLO Wilson coefficient $C_7(m_b)$ in model III-B is positive and disfavered by the measured value of isospin symmetry breaking $\Delta_{0-}^{exp} (K^*\gamma) = (3.9 \pm 4.8)$, but still can not be excluded if we take the large errors into account; (d) the CP asymmetry \acp(B \to \rho \gamma) in model III-B has an opposite sign with the one in the standard model (SM), which may be used as a good observable to distinguish the SM from model III-B; (e) the isospin symmetry breaking $\Delta(\rho\gamma)$ is less than 10% in the region of $\gamma = [ 40 \sim 70]^\circ$ preferred by the global fit result, but can be as large as 20 to 40% in the regions of $\gamma \leq 10^\circ$ and $\gamma \geq 120^\circ$. The SM and model III-B predictions for $\Delta(\rho \gamma)$ are opposite in sign for small or large values of the CKM angles; (f) the U-spin symmetry breaking $\Delta U(K^*,\rho)$ in the SM and the general two-Higgs-doublet models is generally small in size: $\sim 10^{-7}$.Comment: Revtex, 38 pages with 14 eps figures, minor correction

A Finite Element Investigation into the Changing Channel Angular Extrusion of Brass Alloy

Abstract. This study investigates a novel changing channel angular (CCA) extrusion process, in which high strains are induced within the billet by passing it through a series of channels of unequal cross-sections arranged such that they form specified internal angles. Using commercial DEFORM TM 2D rigid-plastic finite element code, the plastic deformation behavior of CuZn37 brass alloy is examined during one-turn and two-turn CCA extrusion processing in dies with internal angles of φ =90 o , 120 o , 135 o or 150 o , respectively. The simulations focus specifically on the effects of the processing conditions on the effective strain, the rotation angle and the effective stress induced within the extruded billet. The numerical results provide valuable insights into the shear plastic deformation behavior of CuZn37 brass alloy during the CCA extrusion process. Introduction In general, rolling, extrusion and forging processes subject the working material to very high strains. The resulting plastic deformation causes a significant change in the physical and mechanical properties of the material. Accordingly, there are significant benefits to be gained from deforming metallic alloys under very high levels of plastic strain. The equal channel angular (ECA) extrusion process (also known as equal channel angular pressing (ECAP)) was first developed by Segal et al. [1-2] as a means of inducing large plastic strains within metallic workpieces without causing a significant change in their outer dimensions. More recently, Liu et al. [3] presented a novel changing channel angular (CCA) extrusion method designed to reduce the tensile stress within the workpiece and to increase the hydrostatic pressure during the extrusion process. Kim [4] used commercial DEFORM TM 2D software to perform a finite element analysis (FEA) investigation into the formation of corner gaps between the die and the workpiece during the plane strain ECAP process. In analyzing the multiple-pass ECAP process, Figueiredo et al. [5] neglected the strain path effect and predicted the material deformation behavior in each pass using a single stress-effective strain curve. Meanwhile, the present authors [6] applied a FE method to investigate the plastic deformation behavior of Ti-6Al-4V titanium alloy during one-and two-turn ECA extrusion. The current study uses DEFORM TM 2D FE code to investigate the plastic deformation behavior of CuZn37 brass alloy during one-and two-turn CCA extrusion processing, in which high strains are induced within the billet by passing it through a series of channels of unequal cross-sections arranged such that they form specified internal angles. The simulations focus particularly on the effects of the CCA processing conditions on the distributions of the effective strain, rotation angle and effective stress, respectively, within the extruded workpiece

Electronic Properties of Boron and Nitrogen doped graphene: A first principles study

Effect of doping of graphene either by Boron (B), Nitrogen (N) or co-doped by B and N is studied using density functional theory. Our extensive band structure and density of states calculations indicate that upon doping by N (electron doping), the Dirac point in the graphene band structure shifts below the Fermi level and an energy gap appears at the high symmetric K-point. On the other hand, by B (hole doping), the Dirac point shifts above the Fermi level and a gap appears. Upon co-doping of graphene by B and N, the energy gap between valence and conduction bands appears at Fermi level and the system behaves as narrow gap semiconductor. Obtained results are found to be in well agreement with available experimental findings.Comment: 11 pages, 4 figures, 1 table, submitted to J. Nanopart. Re

Novel Ge–Ga–Te–CsBr Glass System with Ultrahigh Resolvability of Halide

International audienceCO2 molecule, one of the main molecules to create new life, should be probed accurately to detect the existence of life in exoplanets. The primary signature of CO2 molecule is approximately 15 μm, and traditional S- and Se-based glass fibers are unsuitable. Thus, Te-based glass is the only ideal candidate glass for far-infrared detection. In this study, a new kind of Te-based chalcohalide glass system was discovered with relatively stable and large optical band gap. A traditional melt-quenching method was adopted to prepare a series of (Ge15Ga10Te75)100-x (CsBr)x chalcogenide glass samples. Experiment results indicate that the glass-forming ability and thermal properties of glass samples were improved when CsBr was added in the host of Ge–Ga–Te glass. Ge–Ga–Te glass could remarkably dissolve CsBr content as much as 85 at.%, which is the highest halide content in all reports for Te-based chalcohalide glasses. Moreover, ΔT values of these glass samples were all above 100 °C. The glass sample (Ge15Ga10Te75)65 (CsBr)35 with ΔT of 119 °C was the largest, which was 7 °C larger than that of Ge15Ga10Te75 host glass. The infrared transmission spectra of these glasses show that the far-infrared cut-off wavelengths of (Ge15Ga10Te75)100-x (CsBr)x chalcogenide glasses were all beyond 25 μm. In conclusion, (Ge15Ga10Te75)100-x (CsBr)x chalcogenide glasses are potential materials for far-infrared optical applicatio