“慢新闻”:传统媒体的应对之道

随着新闻表现形态和传播渠道的日益增加,新闻生产进入了浮躁和迷失交织的时代,信息量在膨胀的同时并没有为我们提供足够的经得起时间考验的时代纪录.很多人淹没在碎片化的信息中难以自拔.因此,新闻传播中的快并非都是优点,慢也并非均是缺点,传统媒体如果能够静下心来以深入的态度、以广阔的视野去描述社会的“画面”,那么这种慢就有可能成为传统媒体应对网络媒体冲击的有效策略.     

Progressive collapse analysis of concrete-filled steel tubular frames with semi-rigid connections

A 9-story concrete-filled steel tubular frame model is used to analyze the response of joints due to sudden column loss. Three different models are developed and compared to study the efficiency and feasibility of simulation, which include substructure model, beam element model and solid element model. The comparison results show that the substructure model has a satisfying capability, calculation efficiency and accuracy to predict the concerned joints as well as the overall framework. Based on the substructure model and a kind of semi-rigid connection for concretefilled square hollow section steel column proposed in this paper, the nonlinear dynamic analyses are conducted by the alternate path method. It is found that the removal of the ground inner column brings high-level joint moments and comparatively low-level axial tension forces. The initial stiffness and transmitted ultimate moment of the semi-rigid connection are the main factors that influence the frame behavior, and their lower limit should be guaranteed to resist collapse. Reduced ultimate moment results in drastic displacement and axial force development, which may bring progressive collapse. The higher initial stiffness ensures that the structure has a stronger capacity to resist progressive collapse.     

一个求解非线性互补问题的光滑化全局收敛性算法

求解非线性互补问题的一种方法是将其转化为非光滑方程组。本文通过引进一个基于Fischer-Burmeister函数的光滑NCP函数[8],建立了求解P0函数非线性互补问题的一个新的光滑牛顿算法。这个算法在每步迭代中只需要解一个光滑方程且不要求给出具体光滑因子下降的过程。在一定的条件下,证明了该算法的全局收敛性。数值试验表明该算法是有效的.     

语用学对大学英语教学的影响

众所周知,语用学是语言学的一个分支,它研究语言在使用中或在语境中的意义,研究说话人如何说话以及听话人如何理解话语。本文通过对语用学主要理论进行的阐述,进而分析了语用学对大学英语教学的影响。     

试析新兴词语模“X控”

新兴词语模“x控”源于日语,“x控”中的模槽“x”在构造上有较大的选择性和灵活性,模标“控”标示“x控”总体上是体词性的,“x控”具有极强的新生类推潜能。进入当代汉语系统后。“x控”在一定程度上发生了汉化,主要表现在语义上的扩大化和形式上的汉语化。“x控”很好地达到了语言的简约性和明确性的平衡,利用网络自由交流平台和人们求新猎奇的心理,在短时间内迅速发展扩大。     

安徽寿县方言古入声字的归调

安徽省寿县方言属中厚官话,但古入声字在今寿县方言的归类并不与中原官话的分派规律一致,而呈现出自己的特点。文章列出了寺县方言的声韵调系统,指出了入声字的特殊分派这种现象。     

The feedback interconnection of lumped linear time-invariant systems

This paper considers the feedback interconnection of two multi-input multi-output subsystems characterized by rational transfer functions ₁ and functions are not assumed to be proper nor exponentially stableThe effect of output disturbances on stability is taken into account. Ten examples are given to show that instabilities may appear anywhere around the loop. Next, under a sequence of successively more restrictive assumptions, we prove four sets of necessary and sufficient conditions for the exponential stability of the system. Using coprime factorizations, we obtain four equivalent expressions for the system characteristic polynomial. Two stability tests are derived, the first one is based exclusively on transfer functions, the second is based on the characteristic polynomial. The paper ends by providing translation rules for reformulating all definitions and theorems for the discrete-time case (i.e. instead of Laplace transforms use Z-transforms, etc.).     

Development of an ε-type actuator for enhancing high-speed electro-pneumatic ejector valve performance

A novel ε-type solenoid actuator is proposed to improve the dynamic response of electro-pneumatic ejector valves by reducing moving mass weight. A finite element analysis （FEA） model has been developed to describe the static and dynamic operations of the valves. Compared with a conventional E-type actuator, the proposed ε-type actuator reduced the moving mass weight by almost 65% without significant loss of solenoid force, and reduced the response time （RT） typically by 20%. Prototype valves were designed and fabricated based on the proposed ε-type actuator model. An experimental setup was also established to investigate the dynamic characteristics of valves. The experimental results of the dynamics of valves agreed well with simulations, indicating the validity of the FEA model.     

Development of a miniature silicon wafer fuel cell using L-ascorbic acid as fuel

In the current studies a miniature silicon wafer fuel cell （FC） using L-ascorbic acid as fuel was developed. The cell employs L-ascorbic acid and air as reactants and a thin polymer electrolyte as a separator. Inductively coupled plasma （ICP） silicon etching was employed to fabricate high aspect-ratio columns on the silicon substrate to increase the surface area. A thin platinum layer deposited directly on the silicon surface by the sputtering was used as the catalyst layer for L-ascorbic acid electro-oxidation. Cyclic voltammetry shows that the oxidation of L-ascorbic acid on the sputtered platinum layer is irreversible and that the onset potentials for the oxidation of L-ascorbic acid are from 0.27 V to 0.35 V versus an Ag/AgCl reference electrode. It is found that at the room temperature, with 1 mol/L L-ascorbic acid/PBS （phosphate buffered solution） solution pumped to the anode at 1 ml/min flow rate and air spontaneously diffusing to the cathode as the oxidant, the maximum output power density of the cell was 1.95 mW/cm^2 at a current density of 10 mA/cm^2.     

Forms of assessment and their potential for enhancing learning: conceptual and cultural issues

Assessment has become an important topic of debate and even reform in many Western countries. It is equally important in other regions of the world, although less subject to reform. Yet discussions of assessment across cultural boundaries are not frequent and in a globalizing world this can be problematic. The purposes of this article, therefore, are to review concepts such as ‘formative’ and ‘summative’ assessment and how they have developed over time. A focus of this review will be to identify the implications of different kinds of assessment for student learning, especially in relation to the cultural contexts in which they take place. The article will argue that different forms of assessment can be directed towards different learning purposes, especially where cultural pressures dictate certain kinds of assessment practices. Valorizing one form of assessment over another may well be counterproductive in particular cultural contexts.