63 research outputs found
Design and Implementation of Office Automation Management System for an Organization
随着IT技术的长足发展,政府管理者逐渐认识到使用信息化手段能够使得政府日常办公管理更加快捷和高效,日常办公自动化管理系统在技术和应用上得到了的快速发展。利用软件技术的自动化、先进性和快速计算等特点,构建政府办公管理自动化管理系统,能够将政府工作人员从繁琐、无序、重复的日常办公工作中解放出来,办公管理的人力成本和物力成本都大大降低,从整体上提高了政府办公效率,也使得政府日常办公和管理规范化、合理化、高效化,使管理趋于完善,为百姓提供更好的服务。 系统在分析与设计方面遵循了软件工程的原则,深入调研政府日常工作,首先对政府办公自动化系统进行了可行性论证,然后调研办公管理自动化系统需求,并对用户角色...With the rapid development of IT technology, the government has gradually realized that the use of information technology to make the daily office management more efficient and efficient, daily office automation management system in technology and application has been rapid development. With the characteristics of automation, advanced and fast calculation of software technology, the government man...学位:工程硕士院系专业:软件学院_软件工程学号:X201323180
Questions management system based on SHA-1 safety certification
本系统是运用可视化编程工具Delphi开发并结合SHA-1的信息安全认证技术的题库管理系统.利用Delphi所提供的各种面向对象的开发工具,建立系统应用原型,然后进行需求迭代,不断修正和改进,直到形成满意的可行系统,并在系统里通过SHA-1数字签名技术实现对密码的加密。该系统结构良好、使用方便,题库数据输入简单,系统能够实现人工选题和随机抽题两大功能进行组卷,包括后台数据库的建立、维护以及前端应用程序的开发两个方面。该系统有安全的用户登录模块、方便快捷的浏览界面、易于操作的功能模块。本文的分析基于知识点的试题库结构基础上,阐述以知识点难度系数和题型为主要控制参数的组卷算法的建立与实现方法,并且...This system is a management system of the questions which using Delphi visual programming tool for development in combination with SHA-1 authentication technology of information security. It utilizes a variety of object-oriented development tools Delphi provided, establishes a prototype for system application, and then carries on an iteration of needs, modifies and improves the results constantly,...学位:工学硕士院系专业:信息科学与技术学院计算机科学系_计算机应用技术学号:X200433001
Research and Design of CMOS Wideband Frequency Synthesizer
随着宽带无线技术的发展,通信系统对频率源提出了更高的要求,频率合成技术是人们获得可控频率源的主要途径,该技术的载体——频率合成器,是通信系统中的核心模块及决定通信质量的关键因素。 本文系统地分析了锁相环频率合成及∑-Δ调制技术的原理,并通过Verilog\Verilog-A对∑-Δ小数频率合成器进行系统行为级建模,以此分析模块参数对系统动态特性的影响,并借助该模型加速设计中仿真的速度。文中通过使用25bitMASH1-1-1∑-Δ调制器,实现了小于2Hz的输出频率分辨率;并引入了基于环形振荡原理的伪随机数发生器,有效地降低了∑-Δ调制器的量化噪声;通过在鉴频鉴相器-电荷泵系统引入分流支路,最...As the development of wideband wireless technology, the demand of frequency source is much stricter in communication system. Frequency synthesis technology is the major method to get a controllable frequency source. Frequency synthesizer, which is the realization of frequency synthesis technology, is a main building block in communication system and the key factor of communication quality. In ...学位:工学硕士院系专业:物理与机电工程学院物理学系_微电子学与固体电子学学号:1982007115229
统计思想认识
我国社会主义统计理论和实践已经过六十多年的探索和发展了。在社会主义市场经济发展的今天,总结有益经验,对推动统计理论的发展和统计工作的改革有着重要的意义。坚持毛泽东思想、邓小平理论、"三个代表"重要思想、科学发展观、习近平新时代中国特色社会主义思想对统计工作的指导,最关键是坚持"实事求是"这一重要理念。"实事求是"无疑是统计部门最主要的统计思想
基于标准CMOS工艺的一款宽带限幅放大器芯片设计
采用SMIC0.35μmCMOS混合信号工艺来设计开发一款适用于SDHSTM-16的光接收机前端限幅放大器芯片。该限幅放大器的设计采用了电容中和技术来实现带宽的扩展,可满足2.5Gbps速率要求,芯片电路拥有信号丢失检测和自动静噪功能。芯片版图的参数提取仿真表明:芯片最小输入动态范围可达2mV,50Ω负载上的双端输出摆幅约为1400mVpp,在3.3V供电下静态功耗仅为66mW,动态功耗为105mW,有实际推广价值
Artificial local magnetic field inhomogeneity enhances T2 relaxivity
磁性探针作为分子影像技术中的磁共振成像(MRI)造影剂在医学诊断中发挥着重要作用。为满足实际诊断中的准确性和精确性要求,科研工作者们长期致力于发展高性能的MRI造影剂以降低高剂量的使用带来的潜在风险。该文章指出了探针聚集体中局域磁场不均匀性是影响T2弛豫效能的关键因素。该文章首次利用磁场不均匀性因素阐明了单个探针和它们聚集体的MRI造影剂之间的相互关系,将可能成为弥补探针聚集体的造影剂理论的空白,并为发展新型高效的MRI造影剂提供重要参考。
该论文共同第一作者为博士后周子健和博士生田蕊,通讯作者为陈小元教授和聂立铭博士,部分工作得到我校物理学系王瑞方教授和化学化工学院高锦豪教授的支持。【Abstract】Clustering of magnetic nanoparticles (MNPs) is perhaps the most effective, yet intriguing strategy to enhance T2 relaxivity in magnetic resonance imaging (MRI). However, the underlying mechanism is still not fully understood and the attempts to generalize the classic outersphere theory from single particles to clusters have been found to be inadequate. Here we show that clustering of MNPs enhances local field inhomogeneity due to reduced field symmetry, which can be further elevated by artificially involving iron oxide NPs with heterogeneous geometries in terms of size and shape. The r2 values of iron oxide clusters and Landau–Lifshitz–Gilbert simulations confirmed our hypothesis, indicating that solving magnetic field inhomogeneity may become a powerful way to build correlation between magnetization and T2 relaxivity of MNPs, especially magnetic clusters. This study provides a simple yet distinct mechanism to interpret T2 relaxivity of MNPs, which is crucial to the design of high-performance MRI contrast agents.This work was supported by the National Science Foundation of China (81571744 and 81601489), the National Basic Research Program of China (863 Program 2015AA020502), the Fundamental Research Funds for the Central Universities (20720170065), the Science Foundation of Fujian Province (No. 2014Y2004), and by the Intramural Research Program (IRP), National Institute of Biomedical Imaging and Bioengineering (NIBIB), National Institutes of Health (NIH).
研究工作得到了国家自然科学基金委、国家高技术研究发展计划863项目、福建省重大研发平台项目和美国NIH Intramural Research Program的资助
Artificial local magnetic field inhomogeneity enhances T2 relaxivity
磁性探针作为分子影像技术中的磁共振成像(MRI)造影剂在医学诊断中发挥着重要作用。为满足实际诊断中的准确性和精确性要求,科研工作者们长期致力于发展高性能的MRI造影剂以降低高剂量的使用带来的潜在风险。该文章指出了探针聚集体中局域磁场不均匀性是影响T2弛豫效能的关键因素。该文章首次利用磁场不均匀性因素阐明了单个探针和它们聚集体的MRI造影剂之间的相互关系,将可能成为弥补探针聚集体的造影剂理论的空白,并为发展新型高效的MRI造影剂提供重要参考。
该论文共同第一作者为博士后周子健和博士生田蕊,通讯作者为陈小元教授和聂立铭博士,部分工作得到我校物理学系王瑞方教授和化学化工学院高锦豪教授的支持。【Abstract】Clustering of magnetic nanoparticles (MNPs) is perhaps the most effective, yet intriguing strategy to enhance T2 relaxivity in magnetic resonance imaging (MRI). However, the underlying mechanism is still not fully understood and the attempts to generalize the classic outersphere theory from single particles to clusters have been found to be inadequate. Here we show that clustering of MNPs enhances local field inhomogeneity due to reduced field symmetry, which can be further elevated by artificially involving iron oxide NPs with heterogeneous geometries in terms of size and shape. The r2 values of iron oxide clusters and Landau–Lifshitz–Gilbert simulations confirmed our hypothesis, indicating that solving magnetic field inhomogeneity may become a powerful way to build correlation between magnetization and T2 relaxivity of MNPs, especially magnetic clusters. This study provides a simple yet distinct mechanism to interpret T2 relaxivity of MNPs, which is crucial to the design of high-performance MRI contrast agents.This work was supported by the National Science Foundation of China (81571744 and 81601489), the National Basic Research Program of China (863 Program 2015AA020502), the Fundamental Research Funds for the Central Universities (20720170065), the Science Foundation of Fujian Province (No. 2014Y2004), and by the Intramural Research Program (IRP), National Institute of Biomedical Imaging and Bioengineering (NIBIB), National Institutes of Health (NIH).
研究工作得到了国家自然科学基金委、国家高技术研究发展计划863项目、福建省重大研发平台项目和美国NIH Intramural Research Program的资助
福建主要港口外轮压舱水生物的分布及其潜在入侵威胁
根据2006~2007年间采自福建省4个主要港口12艘外轮(包括8条集装箱船和4条散货船)的压舱水样品,研究压舱水生物的分布特点,结果表明进入该水域的外来船舶压舱水生物物种丰富度和个体丰度高,共发现浮游植物7门86属240种(包括60种赤潮生物)和浮游动物5门30属52种;经3种网目(20,77,和160μm)筛网收集的不同粒径生物的平均丰度分别为:动物38858.3 ind./m3(粒径77~160μm)和782.3 ind./m3(粒径>160μm);植物3625.0 cells./dm3(粒径20~77μm)和134.1 cells./dm3(粒径77~160μm)。压舱水生物的分布及生存状态与水样的盐度及水龄相关。初步评估外来压舱水生物排放对福建沿海的潜在入侵风险
福建外来船舶压舱水中浮游植物种类组成与丰度及其影响因素的初步研究
2006~2008年间对进入福建沿海4个主要港口的12艘国际航船所携带的压舱水进行浮游植物种类组成和丰度分布的调查.此调查共检测出浮游植物7个门86属239种(含变种和变型),77μm孔径网滤样和20μm孔径网滤样的平均藻类丰度分别为1.2×102cells/dm3(变动在0~9.1×102cells/dm3间)和3.4×103cells/dm3(变动在0~3.0×104cells/dm3间).同时对其中6艘船舶的压舱水样品用f/2培养基培养,共有13种硅藻和1种甲藻被成功培养.文中还分析了压舱水中浮游植物丰度与盐度、水龄的关系,并结合历史资料讨论了压舱水里各类浮游植物的分布
中国东南沿海港口外轮压舱水生物的调查
随机选取东南沿海港口的17艘外来船舶(含8条集装箱船和9条散货船)作为监测对象,进行压舱水浮游植物及动物的物种鉴定和丰度测定,并对监测数据进行统计学分析。检出分属于7个浮游植物门类和5个动物门类的309种外来压舱水生物(包括60种赤潮生物)。外轮压舱水生物的分布及生存状态与水样的水龄和盐度相关。船舶压舱水排放是大家熟知的外来水生生物入侵的主要媒介。本调查结果表明,中国东南沿海外来散货船的压舱水排放所具的潜在生物入侵风险比集装箱船更应受关注
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