Velocity and turbulence characteristics in an open channel with multi-row staggered vegetation patches

A staggered distribution of vegetation is very common in nature,which might significantly affect the flow structure.To investigate its impact,three rows of stag...     

浅析建立企业标准体系必须结合企业自身实际情况

目前，很多企业已经建立了GB／T19001、GB／T28001、GB／T24001管理体系，为了在更大的范围和更深的层次上提高企业的管理水平，一些企业还在寻求更多管理体系的认证或确认，还有些企业在寻求不同管理体系的整合和提高，按照GB／T15496、GB／T15497、GB／T15498和GB／T19273的2003版标准建立的企业标准体系也是规范企业所有的管理工作的有效手段。对于有管理经验积累的企业而言，管理体系的运行在一定时期后，企业标准化水平会得到一定提高。但是，如何不断提高运行的有效性与更好地协调各管理体系的兼容性，是摆在我们面前的一个新课题。笔者结合本公司建立企业标准体系的实践经验，阐述了建立企业标准体系，实现企业管理水平持续改进必须要结合企业自身实际情况。     

基于LCC理论的软件项目多目标权衡

传统的软件项目成本模型只反映出与工作量有关的费用,对于因质量不足而引起的成本无法度量.将全寿命周期成本(LCC)理论应用于软件项目成本计算,按照分部分项方法建立了软件项目的完全成本模型.在软件项目工期-成本二维权衡模型的基础上,通过设置多级指标体系对软件项目质量进行量化,从而将软件质量纳入权衡目标,在此基础上构建了软件项目工期、成本、质量的多目标权衡离散模型,运用改进的禁忌搜索算法求解模型,以可视化三维曲面输出帕累托非劣解,最后分析了项目决策者获得项目最佳实施模式的途径.     

The working mechanism of organic photovoltaic cell by using copper phthalocyanine as exciton blocking layer

We demonstrate the working mechanism of organic photovoltaic (OPV) cell with copper phthalocyanine (CuPc) as exciton blocking layer (EBL). The new EBL material CuPc, commonly has been used as electron donor in the organic solar cells due to its electron-donating and hole-transporting properties. But here we proves that the α-polymorph CuPc layer can transfer electrons to Al cathode through the half-filled b_1g level, this mechanism is different from that of general EBL material with larger band gap and electron-transporting property, which is based on damage states induced by the heat of evaporating Al.     

Strength,strain capacity and toughness of five dual-phase pipeline steels

The effect of microstructures on strength, strain capacity and low temperature toughness of a micro-alloyed pipeline steel was elucidated. Five various dual-pha...     

Genome-Wide Identification of TaSAUR Gene Family Members in Hexaploid Wheat and Functional Characterization of TaSAUR66-5B in Improving Nitrogen Use Efficiency

Excessive input of nitrogen fertilizer not only causes a great waste of resources but brings about a series of ecological and environmental problems. Although Small Auxin Up-regulated RNAs (SAURs) participate in diverse biological processes, the function of SAURs in the nitrogen starvation response has not been well-studied. Here, we identified 308 TaSAURs in wheat and divided them into 10 subfamilies. The promoter regions of most TaSAURs contain hormone responsive elements, and their expression levels change under the treatment of different hormones, such as IAA, MeJA, and ABA. Interestingly, overexpression of one of the TaSAUR family members, a nitrogen starvation responsive gene, TaSAUR66-5B, can promote the growth of Arabidopsis and wheat roots. In addition, overexpression of TaSAUR66-5B in Arabidopsis up-regulates the expression levels of auxin biosynthesis related genes, suggesting that overexpression TaSAUR66-5B may promote root growth by increasing the biosynthesis of auxin. Furthermore, overexpression of TaSAUR66-5B in wheat can increase the biomass and grain yields of transgenic plants, as well as the nitrogen concentration and accumulation of both shoots and grains, especially under low nitrogen conditions. This study provides important genomic information of the TaSAUR gene family and lays a foundation for elucidating the functions of TaSAURs in improving nitrogen utilization efficiency in wheat.     

2006—2010 年中英两国主流报纸对麻疹疫苗的科技报道研究

本文遴选2006-2010年中英两国主流报纸对麻疹疫苗和MMR的新闻报道样本,采用内容分析方法以“科学的确定性与不确定”和“政府政策意见趋向”为主线分析了不同媒体环境下针对防治麻疹病疫苗的科学报道模式。通过比较研究中西方不同国家的政府、媒体以及科学家如何针对麻疹疫苗争议对公众进行正确健康疏导以及危机处理方式,拓展了科学普及的研究视野并试图从中总结出更加合理的科技报道模式。科学争议以及危机处理需要科学界与媒体正确的引导,随着网络科技报道数量的增加,传统媒体需要重视其他渠道的科技信息,尤其是来自于科学界的信息,从而对原有科技报道模式做出调整和改善。     

法国电信IPTV的实践及其对中国数字电视发展的借鉴意义

“MaLigne TV”是法国电信IPTV部署的一个实例．通过为用户提供丰富的节目内容和完善的服务，“MaLigne TV”获得了巨大的成功。以此为基础，结合实际环境．讨论了在中国部署IPTV面临的问题和可能的解决思路。     

Data-dependent sampling of two-dimensional signals

Samples taken at scattered points of a finite-support two-dimensional signal can be interpolated to recover an approximation of the original signal. Given a bound on the number of samples, where should they be placed to enable the most accurate reconstruction? Or, given an error bound for the reconstruction, what is the minimum number of samples required, and where should they be placed? In this paper we introduce search schemes that provide good candidate solutions to these problems, for digital signals. Natural Neighbour Interpolation is used in iterative sample removal and movement processes to obtain sparse sample patterns. For pictures and Digital Elevation Models, fewer samples are required if the interpolant is onlyC ⁰ continuous at the data sites, than if it isC ¹. Retained samples lie on the ridges and valleys of the laplacian.     

电路板雕刻过程中的刀路生成与规划

首先分析了电路板的常用制作方法,然后介绍了一种既能减少污染,又能保证加工精度与效率的基于物理雕刻的电路板雕刻机系统.主要对电路板雕刻过程中的刀路生成作了详细论述,并在采用环切与行切相结合的加工方法的基础上,提出了一种基于电路板雕刻的行切刀路规划算法,最后用VC 编写了相应的程序,经程序验证此算法准确可靠,能够满足电路板的加工要求.