Expression and localization of a novel phosducin-like protein from amphioxus Branchiostoma belcheri

A full length amphioxus cDNA, encoding a novel phosducin-like protein (Amphi-PhLP),was identified for the first time from the gut cDNA library of Branchiostoma belched. It is comprised of 1 550 bp and an open reading frame (ORF) of 241 amino acids, with a predicted molecular mass of approximately 28 kDa. In situ hybridization histocbemistry revealed a tissue-specific expression pattern of Amphi-PhLP with the high levels in the ovary, and at a lower level in the hind gut and testis, hepatic caecum, gill, endostyle, and epipharyngeal groove, while it was absent in the muscle, neural tube and notochord. In the Chinese Hamster Ovary (CHO) cells transfected with the expression plasmid pEGFP-NIIAmphi-PhLP, the fusion protein was targeted in the cytoplasm of CHO cells, suggesting that Amphi-PhLP is a cytosolic protein. This work may provide a framework for further understanding of the physiological function of Amphi-PhLP in B. belcheri.     

浅谈属地化管理后地质勘查单位的改革

文章阐述了地质勘查单位体制改革的必要性 ,认为只有解放思想、转变观念、调整产业结构、发挥自身优势 ,才能加快地质勘查单位改革的步伐 ,提出了抓住机遇 ,加速地质勘查单位改革和发展的对策与思路     

基于接收机位置信息的GNSS干扰源定位技术

全球卫星导航系统（GNSS）目前得到了十分广泛的应用,但是GNSS信号到达地面的功率很低,同时民用信号的格式是公开的,因此极易受到各种无意和人为故意的干扰,会对GNSS定位和授时的精度造成影响．查找和消除干扰源十分重要,目前通用的干扰源查找手段是采用测向设备实现干扰源的交叉定位,但在不知道GNSS干扰源的大致位置时,采用测向设备查找干扰源将耗费很长的时间．如果能够通过提取一些通用接收机的输出量实现干扰源的粗定位,就可以为测向定位提供初始参考位置和大概的查找范围．本文利用几乎所有的通用接收机都能输出的位置信息实现干扰源的粗定位,随着GNSS接收机逼近干扰源,会造成接收机位置信息的丢失,随着GNSS接收机远离干扰源,接收机又会重新获取位置信息,本文利用一定区域内众多受干扰的接收机的位置信息丢失点和位置信息重捕获点来实现干扰源的粗定位．通过仿真验证,分析了该技术的定位误差,仿真结果表明,该方法能够实现GNSS干扰源的粗定位,为进一步准确查找干扰源提供位置参考．      

一种支持篡改定位的电子航海图零水印研究

本文针对电子航海图（ENC）使用过程中面临的数据安全问题,结合S-57标准下CRC校验和完整性认证需求,提出了一种顾及点位篡改定位特性的电子航海图零水印算法。该算法在分析ENC物标（要素）中以经纬度表示的离散点位坐标数据分布规律的基础上,构造离散点经纬度坐标数据校验码生成模型,结合离散点经纬度坐标数量对ENC单元格网进行二叉树分块处理,并分块解算基于离散点经纬度坐标校验码的二值序列,通过该二值序列与置乱加密后的水印图像进行异或操作构造零水印图像。算法中离散点的经纬度坐标校验码和格网分块技术的引入,在保证ENC数据精度和满足CRC校验的同时,具备点位篡改定位的特性。试验结果表明,该水印算法具有良好的稳健性、不可见性和一定的篡改定位精度,适用于电子航海图数据的版权保护。     

Embedded technology transfer from an institution and culture nexus perspective: Experiences from the Mombasa-Nairobi Standard-Gauge Railway

Modern railway projects,characterized by"natural monopoly",large investment,and far-reaching influences,are highly dependent on the institutional and cultural environ-ments in China.The countries along the Belt and Road are characterized by weak institutions,unstable politics,and poor technology foundations,which are largely different from China.These factors are severe obstacles to international technology transfer.By summarizing the experiences from the Mombasa-Nairobi Standard-Gauge Railway(SGR)project,this study proposes a framework for embedded technology transfer with a technology-institution-culture nexus.The results indicate that technology localization,including technology standards,management mode,and industrial chain,should be realized in the process of technology transfer.Then,the host government ought to overhaul its institutional and policy framework to support the infrastructure projects.Moreover,the cultural conflicts between the transferor and transferee should be taken seriously.This experience could provide references for other in-ternational infrastructure technology transfers.     

集合变换卡尔曼滤波数据同化方法中的协方差局地化

在集合数据同化中,协方差局地化（covariance localization,CL）方法的使用存在限制。集合转换卡尔曼滤波（ensemble transform Kalman filter,ETKF）作为集合平方根滤波的变种方法,是一种应用较广、计算高效的数据同化方法。本文分析了CL方法应用于ETKF方法的困难,从而改进CL方法使其可以适用于ETKF方法。另外,结合浅水方程,利用Askey函数作为多元局地化函数,提出了一种适用于多元数值模型的CL方法。通过具体实验验证,得到了较好的分析结果。     

The Interpolation Evolution Method for damage localization in structures under seismic excitation

In the aftermath of an earthquake, data acquired by a monitoring system can be used to identify possible damage that occurred in the structure by using algorithms to estimate proper damage features. In this paper, a new method is proposed for damage localization in beam‐like structures under seismic excitation. The proposed algorithm, named the Interpolation Evolution Method (IEM), is based on the combination of two existing methods: the Interpolation Method and the Curvature Evolution Method. Only responses recorded in story accelerations are required to estimate the damage feature with the combined IEM approach. This method does not require a priori knowledge of a “signature” of the structure because it exploits responses recorded during a single strong motion event. Herein, the IEM is applied to case studies of 2 reinforced concrete frames excited by several different ground motions, simulated using nonlinear finite element models and recorded during experimental tests carried out on a shaking table at the University of California, San Diego (USA) and at the University of Basilicata (Italy).     

横观各向同性岩土材料的应变局部化分析

为分析横观各向同性岩土材料的应变局部化行为,推导对应于Lade横观各向同性屈服准则向前欧拉算法的迭代格式及本构矩阵,通过有限元软件ABAQUS的UMAT接口实现相应的程序代码。数值算例调查分析材料主方向对横观各向同性岩土结构的极限承载力和变形局部化模式的影响。结果表明该模型能较好地模拟横观各向同性岩土结构的应变局部化行为。     

Uniqueness and localization analysis of elastic–plastic saturated porous media

Conditions for localization of deformation into a planar (shear) band in the incremental response of elastic–plastic saturated porous media are derived in the case of small strains and rotations. The critical modulus for localization of both undrained and drained conditions are given in terms of the discontinuous bifurcation analysis of the problem. Loss of uniqueness of the response of coupled problems is investigated by means of positiveness of the second‐order work density. From the discussion of drained conditions, it is shown that there are two critical hardening moduli, i.e. lower and upper hardening moduli which, respectively, correspond to single phase material (large permeability) and to undrained conditions (small permeability). In analogy to one‐dimensional results, it is shown that there exists a domain of permeability values where we have loss of stability, but the waves can still propagate. In this domain finite element results do not show pathological mesh dependence, and permeability will play the role of an internal length parameter in dynamic models. The length scale prediction is thus given for multi‐dimensional problems. Copyright © 2001 John Wiley & Sons, Ltd.     

工程结构损伤定位方法的研究

针对三维框架结构等复杂大型土木工程结构,研究基于振动测试的结构损伤诊断方法,提出了1种精确、有效的基于交叉模态应变能(CMSE)的结构损伤诊断方法。传统的模态应变能方法是将损伤前后的同阶模态进行比较,而CMSE方法没有这个限制。此方法最大的优点是需要的模态信息数量少——通常一阶模态就足够了,除此之外CMSE方法不要求进行模态的归一化。文中以三维5层的框架结构的有限元模型对新的方法进行了验证。数值模拟中结构的损伤分为2种情况——单个单元损伤和多个单元的损伤。虽然只给出了三维框架结构的示例,但这种新方法同样适用于其他结构。