船舶舱室正压排烟方案优化及仿真分析

本文主要针对船舶模拟舱室的正压排烟进行研究,以期为现代船舶的消防建设提供参考,将烟控区抽离建模如下文图一,设计正交排烟方案,由实验结果的极差分析得到最优的正压排烟方案即:风速15m/s,出口开度1.2m,进口开度0.3m。针对最优方案,由Fluent仿真分析得到:烟气聚集的地方,温度要高于周围,旋涡的存在导致烟气的滞留,说明针对烟气流动路径的研究将有利于排烟效果的改善。     

Large capacitance and fast polarization response of thin electrolyte dielectrics by spin coating for two-dimensional MoS2 devices

Nano Research - A spin-coating method was applied to obtain thinner and smoother PEO/LiClO4 polymer electrolyte films (EFs) with a lower level of crystallization than those obtained using a...     

Synthesis of ultrathin semicircle-shaped copper nanowires in ethanol solution for low haze flexible transparent conductors

Nano Research - Copper nanowires (CuNWs) are becoming an indispensable item for next-generation transparent optical devices due to their excellent conductivity and transparency. In this work,...     

Defense frontier analysis of quantum cryptographic systems

When a quantum cryptographic system operates in the presence of background noise, security of the key can be recovered by a procedure called key distillation. A key-distillation scheme effective against so-called individual (bitwise-independent) eavesdropping attacks involves sacrifice of some of the data through privacy amplification. We derive the amount of data sacrifice sufficient to defend against individual eavesdropping attacks in both BB84 and B92 protocols and show in what sense the communication becomes secure as a result. We also compare the secrecy capacity of various quantum cryptosystems, taking into account data sacrifice during key distillation, and conclude that the BB84 protocol may offer better performance characteristics than the B92.     

Generalized spin filtering and an improved derivative-sign binary image method for the extraction of fringe skeletons

Generalized spin filters, including several directional filters such as the directional median filter and the directional binary filter, are proposed for removal of the noise of fringe patterns and the extraction of fringe skeletons with the help of fringe-orientation maps (FOM's). The generalized spin filters can filter off noise on fringe patterns and binary fringe patterns efficiently, without distortion of fringe features. A quadrantal angle filter is developed to filter off the FOM. With these new filters, the derivative-sign binary image (DSBI) method for extraction of fringe skeletons is improved considerably. The improved DSBI method can extract high-density skeletons as well as common density skeletons.     

Interaction of catechin with poly(L-proline)

Summary Catechin binds strongly to both poly(vinylpyrrolidone) and poly(L-proline) in dilute aqueous solution, inducing a collapse of the more flexible poly(vinylpyrrolidone) chains, but forming a microgel with the more extended poly(L-proline) chains. Low concentrations of poly(L-proline) inhibit the discoloration of aqueous solutions of catechin, thereby implicating the ortho hydroxyyl groups in the catechol moiety in the binding process. Modeling shows that the likely binding sites on poly(L-proline) arise from two minor local conformations. These minor conformations are less frequent in poly(-hydroxy-L-proline) than in poly(L-proline), which may explain why catechin interacts more strongly with poly(L-proline) than with poly(-hydroxy-L-proline).     

Design sensitivity analysis and optimization of nonlinear dynamic response for a motorcycle driving on a half-sine bump road

This paper analyses the design sensitivity of a suspension system with material and geometric nonlinearities for a motorcycle structure. The main procedures include nonlinear structural analysis, formulation of the problem with nonlinear dynamic response, design sensitivity analysis, and optimization. The incremental finite element method is used in structural analysis. The stiffness and damping parameters of the suspension system are considered as design variables. The maximum amplitude of nonlinear transient response at the seat is taken as the objective function during the optimization simulation. A more realistic finite element model for the motorcycle structure with elasto-damping elements of different material models is presented. A comparison is made of the optimum designs with and without geometric nonlinear response and is discussed.Nomenclature A amplitude of the excitation function - a ₀,a ₁ time integration constants for the Newmark method - ^t+t C _s secant viscous damping matrix at timet+t - ^t C _T tangent viscous damping matrix at timet - C linear part of ^t C _T - D _i ⁰ initial value of thei-th design variable - D _i instanenous value of thei-th design variables - ^t+t F^(t–1) total internal force vector at the end of iteration (i–1) and timet+t - ^t+t F _(NL) ^(i–1) nonlinear part of ^t+t F^(i–1) - f frequency of the excitation function - ^t+t K _s secant stiffness matrix at timet+t - ^t K _T tangent stiffness matrix at timet - K linear part of ^t K _T - effective stiffness matrix at timet - L distance between the wheel centres - M constant mass matrix - m _T number of solution time steps - NC number of constraint equations - Q nonlinear dynamic equilibrium equation of the structural system - ^t+t R external applied load vector at timet+t - t _e active time interval for the excitation function - ^t U displacement vector of the finite element assemblage at timet - velocity of the finite element assemblage at timet - ^t Ü acceleration vector of the finite element assemblage at timet - ^t+t U ⁽ⁱ⁾ displacement vector of the finite element assemblage at the end of iterationi and timet+t - velocity vector of the finite element assemblage at the end of iterationi and timet+t - ^t+t Ü⁽ⁱ⁾ acceleration vector of the finite element assemblage at the end of iterationi and timet+t - U ⁽ⁱ⁾ vector of displacement increments from the end of iteration (i–1) to the end of iterationi at timet+t - V driving speed of motorcycle - x vector of design variable - () quantities of variation - ₀ objective function - _i i-th constraint equation     

FacetAtlas: multifaceted visualization for rich text corpora

Documents in rich text corpora usually contain multiple facets of information. For example, an article about a specific disease often consists of different facets such as symptom, treatment, cause, diagnosis, prognosis, and prevention. Thus, documents may have different relations based on different facets. Powerful search tools have been developed to help users locate lists of individual documents that are most related to specific keywords. However, there is a lack of effective analysis tools that reveal the multifaceted relations of documents within or cross the document clusters. In this paper, we present FacetAtlas, a multifaceted visualization technique for visually analyzing rich text corpora. FacetAtlas combines search technology with advanced visual analytical tools to convey both global and local patterns simultaneously. We describe several unique aspects of FacetAtlas, including (1) node cliques and multifaceted edges, (2) an optimized density map, and (3) automated opacity pattern enhancement for highlighting visual patterns, (4) interactive context switch between facets. In addition, we demonstrate the power of FacetAtlas through a case study that targets patient education in the health care domain. Our evaluation shows the benefits of this work, especially in support of complex multifaceted data analysis.