Deep Scalogram Representations for Acoustic Scene Classification

Spectrogram representations of acoustic scenes have achieved competitive performance for acoustic scene classification. Yet, the spectrogram alone does not take into account a substantial amount of time-frequency information. In this study, we present an approach for exploring the benefits of deep scalogram representations, extracted in segments from an audio stream. The approach presented firstly transforms the segmented acoustic scenes into bump and morse scalograms, as well as spectrograms; secondly, the spectrograms or scalograms are sent into pre-trained convolutional neural networks; thirdly, the features extracted from a subsequent fully connected layer are fed into (bidirectional) gated recurrent neural networks, which are followed by a single highway layer and a softmax layer; finally, predictions from these three systems are fused by a margin sampling value strategy. We then evaluate the proposed approach using the acoustic scene classification data set of 2017 IEEE AASP Challenge on Detection and Classification of Acoustic Scenes and Events (DCASE). On the evaluation set, an accuracy of 64.0% from bidirectional gated recurrent neural networks is obtained when fusing the spectrogram and the bump scalogram, which is an improvement on the 61.0% baseline result provided by the DCASE 2017 organisers. This result shows that extracted bump scalograms are capable of improving the classification accuracy, when fusing with a spectrogram-based system.      

Heat spreading in a thin longitudinal fin

In view of the trend towards higher power densities in ever shrinking geometries, understanding heat spreading fundamentals is gaining importance. In this paper heat spreading in thin longitudinal geometries is considered. This geometry is of practical interest in one-dimensional Cartesian geometries. A characteristic length is derived and it is shown that this has physical significance for the distance that heat spreads, and for the total amount of heat cooled away. Furthermore, it is investigated when “thin” is a viable assumption. The use of the characteristic length is illustrated for the case of a line source cooling to a plate and for the case of the fins of a plate heatsink. The results are compared to numerical simulations. The work is an extension of the authors' earlier work on heat spreading in infinite longitudinal geometries and heat spreading in infinite and finite circular geometries.     

Heat transfer in dusty fluid with suspended hybrid nanoparticles over a melting surface

The melting effect with the magnetic field performs a significant role in various manufacturing and industrial applications, such as welding, casting, magma-solidification, nuclear engineering, and so forth. The present study focuses on the impact of the melting effect and magnetic field with inhomogeneous heat origination and sink. The formulation of the mathematical model is done by considering fluid with hybrid nanoparticles and dust particles in two different phases. We have considered Fe₂SO₄ and Cu as nanoparticles dispersed in the base fluid water along with suspended dust particles. The set of partial differential equations is reduced by using apt similarity variables and boundary conditions to obtain ordinary differential equations. The numerical solution is approximated using MATLAB-bvp4c adopting the shooting technique. The impact of numerous pertinent physical parameters on the velocity and thermal profiles is plotted and deliberated. Furthermore, the rate of heat flow and friction factor is also tabulated and visualized through the graphs. Streamlines are also drawn to know the behavior of the fluid flow. The rise in values of M_E quickly increases the velocity of the fluid motion but declines the thermal gradient and thickness of its related boundary layer. Also, inclining values of Pr enhance the thermal profile due to the impact of melting.     

Interactive direct illumination in dynamic scenes using graphics APIS

Abstract

We present a progressive refinement system for rendering direct illumination at interactive rates for dynamic scenes using available graphics APIs. We achieve the progression by subdividing object surfaces using a quad‐tree approach. Integrating the visibility and illumination, we can render scenes with soft shadows, taking into account the BRDFs of the scene objects. Our system allows a user to specify the desired frame rates, and the system will achieve such rates with the available time budget. Our system can also render dynamic scenes where the system restores the initial meshes and calculates illumination, producing finer but accurate soft shadows during iterative refinements.     

Second order velocity slip and thermal jump of Cu–water nanofluid over a cone in the presence of nonlinear radiation and nonuniform heat source/sink using homotopy analysis method

The purpose of the present paper is to explore the second order slip effects on nanofluid flow over a vertical cone. The effects of nonlinear thermal radiation and nonuniform heat source/sink are also taken into account. Water with copper nanoparticles is used as nanofluid in this investigation. The governing partial differential equations for the flow are converted into ordinary differential equations by using transformations and then are solved using homotopy analysis method. The influence of various important parameters on velocity, temperature, skin‐friction, and Nusselt number are presented through graphs. Results indicate that the velocity and magnitude of skin friction decrease with a rise in first and second order velocity slips. A raise in either first or second order temperature jump causes a fall in temperature. Nonlinear radiation increases the more rapidly when compared to the linear radiation case.     

潞安矿区煤田钻井造浆土实验研究

针对潞安矿区煤田钻探造浆用土进行了室内实验测试与分析,通过造浆率的测试和造浆改性实验,得出其造浆率极低、利用常规的方法不能调节现场造浆土造浆性能的结论;实验研究了现场造浆土的矿物成分、粒度成分及其造浆后的失水量、胶体率和比重,得出现场土不适合作为泥浆造浆用土,进而对潞安矿区煤田钻孔造浆土进行了推荐。     

浅谈如何做好电力业扩报装工作

随着我国社会经济和科学技术的迅速发展，电力业扩报装工作取得了明显的进步。但是，在业扩报装工作中依然存在许多问题，例如业扩报装的工作时间长、收费的公开度低、工作环节多等，这些问题不仅成为电力用户关注的焦点，对电力企业的售电量也产生了重要的影响。     

低碳混凝土的技术理念与途径思考

从全球碳中和与可持续混凝土发展角度阐述了低碳混凝土的基本概念及全生命周期的减碳与碳汇核心技术理念.从原材料、混凝土设计、制备、施工、服役及再生利用等全生命周期过程提出了低碳混凝土的三大技术途径——直接减碳、间接减碳及碳汇技术，并分析了每个技术途径下的具体减碳技术路线.综述了混凝土的碳排放评价方法和准则，阐释了混凝土碳排放的生命周期评价方法 .提出了低碳混凝土未来的重点研究方向——开发新型胶凝材料以及碳汇技术.     

Analysis of release kinetics of ocular therapeutics from drug releasing contact lenses: Best methods and practices to advance the field

Several methods have been proposed to achieve an extended and controlled release of ocular therapeutics via contact lenses; however, the experimental conditions used to study the drug release vary greatly and significantly influence the release kinetics. In this paper, we examine variations in the release conditions and their effect on the release of both hydrophilic and hydrophobic drugs (ketotifen fumarate, diclofenac sodium, timolol maleate and dexamethasone) from conventional hydrogel and silicone hydrogel lenses. Drug release was studied under different conditions, varying volume, mixing rates, and temperature. Volume had the biggest effect on the release profile, which ironically is the least consistent variable throughout the literature. When a small volume (2–30 mL) was used with no forced mixing and solvent exchange every 24 h, equilibrium was reached promptly much earlier than solvent exchange, significantly damping the drug release rate and artificially extending the release duration, leading to false conclusions. Using a large volume (200–400 mL) with a 30 rpm mixing rate and no solvent exchange, the release rate and total mass released was significantly increased. In general, the release performed in small volumes with no force mixing exhibited cumulative mass release amounts of 3–12 times less than the cumulative release amounts in large volumes with mixing. Increases in mixing rate and temperature resulted in relatively small increases of 1.4 and 1.2 times, respectively in fractional mass released. These results strongly demonstrate the necessity of proper and thorough analysis of release data to assure that equilibrium is not affecting release kinetics. This is paramount for comparison of various controlled drug release methods of therapeutic contact lenses, validation of the potential of lenses as an efficient and effective means of drug delivery, as well as increasing the likelihood of only the most promising methods reaching in vivo studies.