烘缸轴头磨损的应急处理

在纸机连续运转过程中,由于烘缸承受较高的温度和一定的压力,会在烘缸轴承位置出现磨损现象,造成设备无法运转。由于烘缸体积较大,企业一般无备用件,若即刻联系加工修复,不但拆卸运输困难,而且停机时间太长,给生产造成损失,影响企业经济效益。现就烘缸轴承位置出现磨损后现场采用的应急处理办法做一介绍。     

硫酸亚铁还原法在突发性铬(Ⅵ)污染应急处理中的应用研究

针对水源突发性铬(Ⅵ)污染风险,研究了不同反应条件下硫酸亚铁还原沉淀法对铬(Ⅵ)的去除效果。结果表明,硫酸亚铁还原沉淀法是可行的突发性铬(Ⅵ)污染应急处理方法,反应在较短的时间(10 min)内即可达到平衡;在不改变原水pH(7~8)条件下,当硫酸亚铁投加量为16 mg/L,铬(Ⅵ)污染强度为2.00 mg/L时,铬(Ⅵ)去除率达99.1%,出水铬(Ⅵ)与铁质量浓度分别为0.019、0.021 mg/L,满足《生活饮用水卫生标准》(GB 5749—2006)的要求。     

可生存性及紧急算法特征分析

文章主要就无边界网络系统的可生存性问题及其解决方案-紧急算法两个方面进行分析。首先给出了作为网络信息系统发展方向的无边界系统的定义,分析其特征并引出无边界系统环境下的网络安全研究。然后提出满足安全新需求的无边界网络可生存性问题,分析了可生存性必须具备的特征及其与传统安全概念的区别,并简要分析了可生存系统的设计需求。最后着重分析了可以解决无边界网络可生存性问题的紧急算法的特征,给出了紧急算法的两种不同的定义描述,并对比分析了与传统分布式算法的不同,论文还就紧急算法的应用场合和开发策略进行了简单分析。     

Nativism versus neuroconstructivism: Rethinking the study of developmental disorders.

This article argues that one dominant position in psychology, linguistics, neuroscience, and philosophy about how genetic disorders point to the innate specification of dissociated modules in the human brain should be replaced by a dynamic, neuroconstructivist approach in which genes, brain, cognition, and environment interact multidirectionally. The article challenges current thinking about a series of questions: (a) Do significantly better scores in one domain necessarily indicate an intact module? (b) What do scores in the normal range suggest? (c) What is wrong with mental-age matching? (d) Why is the notion of an intact module unlikely? (e) Do developmental disorders suggest associations rather than dissociations? (f) Is the environment the same for atypically developing individuals? The article concludes by examining the implications of taking a neuroconstructivist approach and by arguing that human intelligence is not a state (i.e., not a collection of static, built-in modules that can be intact or impaired) but a process (i.e., the emergent property over developmental time of dynamic, multidirectional interactions between genes, brain, cognition, behavior, and environment) with domain-specific outcomes impossible without the process of development. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Dynamically Driven Emergence in a Nanomagnetic System

Emergent behaviors occur when simple interactions between a system's constituent elements produce properties that the individual elements do not exhibit in isolation. This article reports tunable emergent behaviors observed in domain wall (DW) populations of arrays of interconnected magnetic ring-shaped nanowires under an applied rotating magnetic field. DWs interact stochastically at ring junctions to create mechanisms of DW population loss and gain. These combine to give a dynamic, field-dependent equilibrium DW population that is a robust and emergent property of the array, despite highly varied local magnetic configurations. The magnetic ring arrays’ properties (e.g., non-linear behavior, “fading memory” to changes in field, fabrication repeatability, and scalability) suggest they are an interesting candidate system for realizing reservoir computing (RC), a form of neuromorphic computing, in hardware. By way of example, simulations of ring arrays performing RC approaches 100% success in classifying spoken digits for single speakers.     

基于MIKE21的河道饮用水源地突发污染事故模拟——以赣江南昌段为例

为及时处理赣江南昌段突发性水污染事故,采用MIKE21二维水质模型建立了赣江南昌段水动力模型,通过耦合污染物传输模型研究了该河段上游物质释放和运移扩散过程。模拟过程中,利用2013年赣江水文数据对模型进行率定和验证,在模拟精度符合要求的基础上模拟了2013年赣江南昌段分别在丰、平、枯3种典型水文情势下的突发水污染事故中污染物运移扩散过程。模拟结果表明:在丰、平水文情势下,污染团流过饮用水取水口速度较快,历经2～4 h;枯水水文情势下污染团流过取水口较慢,历时会超过10 h;突发水污染事故对饮用水取水口影响程度受赣江水文情势的影响显著。     

Navigation of carlike robots in an extended dynamic environment with swarm avoidance

In this paper, we propose a new solution to the motion planning and control problem for a team of carlike mobile robots traversing in an extended dynamic environment. Motivated by the emerging necessity to avoid or defend against a swarm of autonomous robots, the wide array of obstacles in this dynamic environment for the first time includes a swarm of boids governed separately by a system of ordinary differential equations. The swarm exhibits collective emergent behaviors, whereas the carlike mobile robots safely navigate to designated targets. We present a set of nonlinear continuous controllers for obstacle, collision, and swarm avoidance. The controllers provide a collision‐free trajectory within a constrained workspace cluttered with various fixed and moving obstacles while satisfying the nonholonomic and kinodynamic constraints associated with the vehicular robotic system. An advantage of the proposed method is the ease in deriving the acceleration‐based control laws from the Lyapunov‐based control scheme. The effectiveness of the control laws is demonstrated via computer simulations. The novelty of this paper lies in the simplicity of the controllers and the ease in the treatment of an extended dynamic environment, which includes swarm avoidance.     

循环水系统泄漏及水质恶化对策

循环水系统泄漏主要是由工艺物料腐蚀和循环水腐蚀引起.泄漏导致水质恶化,加剧沉积和腐蚀的进一步发生,从而降低换热器换热效率.泄漏发生后,应通过调整工艺及水处理方案,控制微生物滋生,采取黏泥剥离等方法,维持水系统正常运行.     

雷达组网探测系统应急巡检路径的优化方法

结合雷达组网探测系统的设计特性和运用特点,以组网雷达重要度和固有可用度等作为约束条件,给出了系统应急巡检路径选择优化模型及其算法,并通过算例进行了分析.     

基于掺长模型非淹没刚性植被水流流速垂向分布的数值解

对非淹没刚性植被的水流流速垂向分布进行了研究,基于恒定均匀流假定,通过单元体的受力分析得到考虑刚性、非淹没植被作用后水体单元流动的控制方程,充分考虑了植被群对混掺长度、植被拖曳力系数、达西—魏斯巴哈摩擦系数的影响,得到了基于混合长度概念的求解非淹没刚性植被水流流速垂向分布的新模型。该模型物理概念清晰,形式简单,可直接计算出摩阻流速。结合本文和Rowinski 等的室内水槽实验资料,采用该模型对非淹没刚性植被流速垂向分布进行了数值模拟,结果表明本文给出新的掺长模型是合理有效的。