种植业水环境面源污染及防治对策研究

种植业生产过程中化肥、农药的过度使用及污水灌溉行为造成了农村水环境的严重污染在农村水环境污染源中,种植业面源污染占有非常高的比例.论文依据国家统计局统计资料,从化肥污染、农药污染、污水灌溉三个角度分析了种植业水环境面源污染的现状,并指出种植业水环境面源污染的危害,在此基础上从立法、宣传教育、农业污染优先控制区划分以及现代农业生产技术等方面,提出了防治种植业水环境面源污染的措施.     

审视与反思：高职学报稿源问题——以《襄阳职业技术学院学报》为例

新形势下,高职学报因为高职院校科研人员能力的制约,评价机制的不合理,办刊特色不鲜明,影响因子较低,编辑工作的主动性、积极性不够,办刊经费不足等原因,造成高职学报稿源量少质差的状况.要从根本上提升高职学报的办刊质量,必须从多措并举留住校内稿源,办出特色,提升学报影响,吸纳稿源,强化编辑危机感、责任感等方面来改变现有高职学报稿源的现状.     

Social influence on endorsement in social Q&A community: Moderating effects of temporal and spatial factors

This study examines the impacts of social influence, which are manifested by popularity and source credibility, on social endorsement in social Q&A community; and how the relationship is impacted by temporal-spatial factors. By collecting panel data from a large platform, the results of an econometric model demonstrate that popularity and source credibility are positively associated with social endorsement. With respect to the moderation effects, the results further show that time distance strengthens the effect of popularity on the social endorsement, but undermines the effect of source credibility; while crowdedness plays the role that strengthens the impact of popularity on the social endorsement, it has no significant moderating effect on the relationship between source credibility and social endorsement. Both theoretical and practical implications are discussed.     

基于FPGA的多相FIR数字滤波器的设计

有限冲击响应滤波器（FIR）被大量用于各种数字通信系统中，实现各种功能．用现场可编程门阵列（FPCA）实现各种功能的FIR滤波器，得到普遍应用．采用FIR直接型滤波器结构，每计算一个数据都要做大量的乘法和加法，计算量非常大，给工程实践的实现带来了很大困难．本文利用FPGA实现多相结构的FIR滤波器，可以大幅度的节约资源，减少运算量．     

(Re)Viewing Reviews: Effects of Emotionality and Valence on Credibility Perceptions in Online Consumer Reviews

This study examines credibility perceptions in online consumer reviews. Specifically, this work investigates the effects of review emotionality (high vs. low), review valence (positive vs. negative), and individuals’ need for affect on source credibility and information credibility. In an online experiment, U.S. adults (N = 327) viewed a product review from Amazon.com varied across four experimental conditions. Results indicate that high-emotionality reviews are perceived as lower in source and information credibility compared to low-emotionality reviews. A moderated mediation model was tested with the source credibility dimensions as possible mediators of information credibility and need for affect as a moderator for the effects of review emotionality. The effects of emotionality on information credibility were significantly mediated by source trustworthiness, and this mediation was moderated by participants’ need for affect, with the credibility-hampering effects of emotionality found only among participants with low and moderate levels of need for affect.     

Screening of plane S waves by an array of rigid piles in poroelastic soil

An array of rigid piles used as a screening barrier for plane shear （S） waves is investigated in a homogeneous unbounded space. The dynamic poroelastic theory of Biot is employed, under the assumption of an incompressible solid grain. Using Fourier-Bessel series, the problem of multiple scattering is solved by imposing continuity conditions and equilibrium conditions at the soil-pile interfaces with the translational addition theorem. A parametric analysis is conducted to investigate the influence of the permeability of poroelastic soil, separation between piles, number of piles and frequency of incident waves on screening effectiveness of the barrier, and the results are compared with those in an elastic soil medium. Computed results show that the intrinsic permeability of the soil medium displays an apparent effect on the screening of plane S waves.     

论一类特殊的Pythagoras数

设x,y,z是正整数.如果x2 y2=z2,则称(x,y,z)是一组Pythagoras数.运用初等方法证明了:恰有12组Pythagoras数(x,y,z)适合6(x y z)=xy.     

From Music to Physics: The Undervalued Legacy of Pythagoras

This paper presents the early investigations about the nature of sound of the Pythagoreans, and how they started a tradition that remains valid up to present times—the use of numbers in representing natural reality. It will touch on the Pythagorean notion of musical harmony, which was extended to the notion of universal harmony. How the Pythagorean ideas have inspired many great works in physics, such as those of Galileo, Kepler and Newton, will also be presented. In exploring the legacy of Pythagoras to physics and the study of the universe, some valuable insights on the nature of science that can inspire budding physicists are extracted.     

大型电视文化专题片《三江源》的文化解读

大型电视文化专题片<三江源>从历史的、民族的、生态的、文化的、和谐的、探寻的几个层面架构起整个专题片,从不同层面折射出三江源独特的人类文化光辉,这是<三江源>产生文化凝聚力和永久魅力的原因所在.     

设计思维导向的开源硬件教学模式构建与应用研究

作为一种开放、智能、灵活的数字化学习工具,开源硬件是培养中小学生设计思维能力的重要载体。为了探索设计思维培养与开源硬件教学实践双向耦合的新路径,文章首先解析了设计思维概念内涵,对典型设计思维培养模型及特征进行分析,并将其解构为更具显性化操作意义的五大核心能力:换位思考、抽象定义、创意构想、原型迭代和迁移应用;其次,汲取设计型学习理论核心要义,借鉴“基于设计的双循环探究模型”,构建了设计思维导向的开源硬件教学模式,从“调查/探究”“设计/再设计”“反思”三个循环过程对其具体应用进行阐释;最后,以“智慧校园生活”为项目主题开展开源硬件教学实践,为新版高中信息技术课程标准中“开源硬件项目设计”模块的教学实施提供范例。