Sub-molecular features of single proteins in solution resolved with scanning tunneling microscopy

Scanning tunneling microscopy (STM) can be used to image individual biological molecules, such as proteins, in vacuum or air. This requires sample dehydration and thus may not reflect the native state of the molecule. Extensive efforts have been made to image single proteins in solution using STM; however, the images have revealed only round or oval shapes with no sub-molecular details. Here, we present the sub-molecular features of streptavidin proteins under physiological conditions using a homebuilt low-leakage-current and highstability liquid phase STM. The N-lobe, C-lobe, and C-terminal tail of the epidermal growth factor receptor kinase domains were also resolved in solution. Our results demonstrate that the structure, morphology, and dynamics of a protein molecule can be examined under physiological conditions by the STM.

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Lot-sizing on a single imperfect machine: ILP models and FPTAS extensions

A single-machine multi-product lot-sizing and sequencing problem is studied. In this problem, items of n different products are manufactured in lots. Demands for products as well as per item processing times are known. There are losses of productivity because of non perfect production. There is also a sequence dependent set-up time between lots of different products. Machine yields and product lead times are assumed to be known deterministic functions. The objective is to minimize the cost of the demand dissatisfaction provided that the total processing time does not exceed a given time limit. We propose two integer linear programming (ILP) models for the NP-hard “fraction defective” case of this problem and compare effectiveness of their ILOG CPLEX realizations with a dynamic programming algorithm in a computer experiment. We also show how an earlier developed fully polynomial time approximation scheme (FPTAS) and one of the ILP models can be extended for a more complex case.     

一种面向数据密集型应用的并行程序执行模型

随着各领域需要处理的数据量越来越大,数据密集型应用也变得越来越被重视.该文提出一种包含数据访存层次和访存冲突等信息的新并行程序执行模型PSRAM(h).针对数据密集型应用以访存为主的特点,PSRAM(h)模型将程序执行时间简化为访存时间,通过分析各程序子段的访存层次和数量来预测串行程序的执行时间,进而通过使用各线程执行时间的最大值来预测并行程序的执行时间.使用PSRAM(h)模型下对最典型的数据密集型应用矩阵向量乘进行分析,在龙芯3A处理器和Intel Xeon E5520处理器两个平台上的测试结果表明,PSRAM(h)模型分析结果与实测结果大部分情况下误差小于20%.由此可见,针对数据密集型应用,PSRAM(h)不但可以给出程序执行时间的下限,还可以有效的预测程序的执行时间.     

基于数据立方体的水电工程建设项目群信息管理系统

本文提出了一水电工程建设项目群信息管理系统,其中建立了包含工程信息数据库、施工动态信息数据库、资源信息数据库的数据仓库,不仅加快了海量信息的传输与同步过程,减少数据冗余,而且还实现了项目群信息与知识的共享。并且,针对某水电工程建设监理企业开发了相应的项目群信息管理系统,为企业的多项目管理、知识共享提供了一良好的平台与基础。     

新疆玛纳斯河灌区莫索湾总干渠梧桐坝跌水公路桥预应力箱梁施工方案

本文对莫索湾总干渠梧桐坝跌水公路桥工程箱梁台座的制作,箱梁钢筋骨架的制作与安装、钢绞线及波纹管安装、模板制作与安装、混凝土的浇筑与养护、预应力的张拉、孔道压浆与封锚及箱梁的防水吊装的施工方法和控制要点,作了详细介绍。工程参考性强,可为其他类似工程建设提供宝贵经验。     

探地雷达在冬季冰下水深探测中的应用研究

本文从理论上分析了探地雷达用于冰下水深探测的基本原理。介绍了采用该项技术对辽河福德店段的探测过程。通过对采集数据处理和图像解释分析,得到河道断面连续水深值,并进行钻取冰眼测量验证,证明探测结果是可靠的。     

A decision support framework for metrics selection in goal-based measurement programs: GQM-DSFMS

Software organizations face challenges in managing and sustaining their measurement programs over time. The complexity of measurement programs increase with exploding number of goals and metrics to collect. At the same time, organizations usually have limited budget and resources for metrics collection. It has been recognized for quite a while that there is the need for prioritizing goals, which then ought to drive the selection of metrics. On the other hand, the dynamic nature of the organizations requires measurement programs to adapt to the changes in the stakeholders, their goals, information needs and priorities. Therefore, it is crucial for organizations to use structured approaches that provide transparency, traceability and guidance in choosing an optimum set of metrics that would address the highest priority information needs considering limited resources. This paper proposes a decision support framework for metrics selection (DSFMS) which is built upon the widely used Goal Question Metric (GQM) approach. The core of the framework includes an iterative goal-based metrics selection process incorporating decision making mechanisms in metrics selection, a pre-defined Attributes/Metrics Repository, and a Traceability Model among GQM elements. We also discuss alternative prioritization and optimization techniques for organizations to tailor the framework according to their needs. The evaluation of the GQM-DSFMS framework was done through a case study in a CMMI Level 3 software company.     

砂石加工系统运行管理合同变更索赔处理——以水布垭水利枢纽为例

结合合同文件和工作实践,针对清江水布垭水利枢纽工程建设中发生的左右岸砂石加工系统生产运行管理合同变更索赔问题,总结了合同变更索赔的审核处理原则、处理程序、处理方式和计算方法,供业务工作者在砂石系统工程招投标及变更索赔中参考。     

水利系统干部人事档案数字信息化建设探索与实践

干部档案数字信息化建设是干部档案工作在信息化时代的必由之路,是提高干部信息管理和利用水平的必然要求。在阐述档案数字信息化概念的基础上,以南京水利科学研究院干部人事档案数字信息化建设为实例,对水利干部人事档案数字信息化建设进行有益探索,提出水利系统干部人事档案数字信息化系统建设的要素确定、基本程序及主要环节,具有实用性和可操作性。     

某工程66kV输电线路工程实施阶段水土保持措施

某66kV输电线路工程是为辽东山区某中型水电站隧洞施工架设的配套输电线路工程,水电站工程的总体水土保持方案已获批复。由于输电线路为临时性工程,初步设计的总体水土保持方案中对施工期间的输电线路工程水土保持设计分析与评价论述,主要为原则性建议,缺乏具体的实施措施。在输电线路工程施工过程中,根据施工单位的施工工艺和现场条件,制定了详细的水土保持措施,为工程实施提供了技术支撑,取得了预期效果。本文对此加以介绍。