421 research outputs found

    网上银行风险的防范与管理

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    本文系统地分析了网上银行的风险种类及其成因,特别是强调了涉及网络系统安全的系统风险,提出操作性强的防范及管理措施

    The Prediction of State-of-charge for Lead-Acid Battery Based on ANFIS Model

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    随着石油能源的日益枯竭和环境污染问题的日益突出,电动汽车将成为未来的主要交通工具得到了人们的普遍的认可。因而,电动汽车的研制和发展得到了各国政府的大力支持和鼓励以及各大汽车公司和科研机构的重视。我国政府也已看到发展研制电动汽车的重大意义,在“八五”、“九五”和“十五”规划中已经把研制开发电动汽车列入重大科技发展项目中。作为电动汽车发展的相关技术之一,电动汽车电池的剩余电量估计系统的研制也逐步的深入并进入实用化阶段。电池剩余电量估计系统的研究及使用,是有效地延长电池使用寿命的一个重要手段。电池剩余电量估计系统不仅能够防止电池过放电或过充,而且对于电动汽车行使过程中起到了汽车汽油表的重要作用。本文...With fuel energy drying up and environment deterioration,EVs(electric vehicles) are comprehensively seen as the main transpoartation tools in the future.Thus, many countries as well as automotive companies support and attach great significance to the research and development of EV. China has also realized the great meaning of developing EV and has put the research and development of EV on the key ...学位:工学博士院系专业:信息科学与技术学院自动化系_控制理论与控制工程学号:20033100

    Analysis and Design of Management Information System for the Fine Work of University Students' Ideological and Political Education

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    大学生思想政治教育工作是高校学生工作的重要内容之一。随着中国社会的快速发展和多元文化的交融,当代大学生的思想呈现多元化、个性化、复杂化发展趋势。为此,新形势下,高校要做好在校学生的思想政治教育,需要引入精细化管理理念,以精准的教育引导和细致的教育服务,致力于学生成长成才的终极目标。高校学生思想政治教育精细化工作的开展,需要依托于信息化技术,将工作中产生的庞大、繁杂的教育工作数据,纳入到管理信息系统中,方便数据采集,实现快捷的数据查询和统计,并将数据处理结果运用到实际的教育工作中,从而提高高校学生思想政治教育工作的总体水平。 本文主要以集美大学诚毅学院为例,结合当前学校的学生思想政治教育精细化...Ideological and political education of college students is an important part of the work for the college students. With the development of society and the blending of multi cultures, the contemporary college students' ides are diversified, personalized and complex. Therefore, under the new situation, in order to do a good job for the ideological and political education, the university should intro...学位:工程硕士院系专业:软件学院_工程硕士(软件工程)学号:X201323088

    修订《水污染防治法》推动循环经济发展

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    循环经济模式是我国经济走向可持续发展的必然选择。我国目前的水资源形势不容乐观。在修订《水污染防治法》的过程中,应当针对我国当前水污染防治工作中存在的一些突出的实际问题,借鉴各地在立法方面的成功经验和做法,加强完善控制工业污染、推广中水回用、促进城市污水处理和推动“节水型社会”建设方面的法律规定,以促进我国循环经济的迅速发展

    Research on Sliding Mode Predictive Controlling Based on Permanent Magnet Synchronous Motor Servo System

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    永磁同步电机(PMSM)的模型是一个多变量,非线性,强耦合的系统,而滑模变结构控制(SMC)具有快速响应,对参数变化及扰动不灵敏,算法简单,易于工程实现等优点。本论文利用滑模预测对永磁同步电机伺服系统电流和速度环展开研究。 结合大量相关文献资料,回顾了交流伺服系统的发展历史,分析了发展现状,并对永磁同步电机的数学模型,矢量控制思想以及空间矢量脉宽调制技术在永磁同步电机上的应用进行了说明。 近三十年来,滑模控制和预测控制在理论和工业应用方面都取得了一定的成果,针对PID控制调节出现的一些问题,采用滑模预测控制加以比较改进。将模型预测控制与滑模控制结合起来,提出了滑模预测控制,这里的结合是既有...Permanent Magnet Synchronous Motor is a typical multi-variable, nonlinear, and strong coupling system . The sliding mode control has the advantages such as fast response , insensitivity to parameter changes and disturbances , simple computing , and easy to implement in engineering . this paper using sliding mode and predictive to research the current and speed loop of PMSM servo syetem . With a l...学位:工学硕士院系专业:信息科学与技术学院自动化系_检测技术与自动化装置学号:2322009115286

    On the respiration and ocean acidification in the coastal ocean

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    呼吸作用和光合作用是海洋生态系统新陈代谢的两个主要过程。通过呼吸作用,海洋微生物消耗氧气,分解有机物质,释放二氧化碳(CO2),产生氢离子。在近岸环境,强烈的呼吸作用被认为是河口和近岸区域缺氧发生的重要条件。在缺氧形成过程中,呼吸作用向水体释放CO2,能进一步加剧水体的酸化。反过来,海洋酸化(OA)对呼吸作用也具有影响作用,能改变浮游细菌对有机物的降解效率。所以呼吸作用和OA过程具有耦合关系,这种耦合作用在缺氧区尤为显著。但目前我们对这种耦合过程的理解还很不足。并且在未来,在全球变化背景下,随着OA和全球暖化程度的加剧,这种耦合过程如何响应更是一个相当复杂的科学命题,相应的研究亟需开展。 本论文以呼吸作用为核心研究内容,选择东海长江口陆架区为主要研究区域,探讨呼吸作用对缺氧形成演化的作用,以及在缺氧形成过程中,呼吸作用介导水体酸化的过程;本论文还辅以一系列受控酸化培养实验,研究OA对呼吸作用的影响,揭示呼吸作用与OA两者相互耦合关系。 在2011-6、2009-8和2011-10三个航次的调查中,东海表层水体群落呼吸(CR)速率变化范围分别为0.6-40.6(平均值±SD:10.2±12.0)、0.3-28.1(平均值±SD:8.6±7.7)和0-10.0(平均值±SD:3.2±2.5)μmolO2L-1day-1。浮游植物和浮游细菌是水体呼吸作用的最主要参与者,90%以上的水体CR由这两部分浮游生物所贡献。而相应地,在表层长江冲淡水(plume)区域(表层盐度≦32.0)和真光层以深非plume区域(表层盐度>32.0),水体呼吸作用分别以浮游植物呼吸和浮游细菌呼吸(BR)为主。结合初级生产力的数据,我们发现,除2011-6航次近岸河口区域外,长江口夏季和秋季水体大部分区域处于异养状态。 长江口缺氧区具有明显的季节性演化过程。通过长江口一系列的现场调查,我们发现,长江口区域中下层水体溶解氧(DO)、溶解无机碳(DIC)和pHT(总氢离子标度,25.0oC)具有显著的季节性和空间变化,DIC和pHT伴随着DO的改变而改变。并在2011年7、8、10三个月,观测到3个缺/低氧区域,其中心分别位于122o40′E,31o30′N;123oE,31oN和123o30′E,30oN。缺氧演化的大体过程为:缺氧区的形成始于春末夏初,在夏季7-8月达到最强盛,从秋季开始衰退,并在冬季完全消失。长江口缺氧区的中心位置存在先由西向东,然后南移的趋势。缺氧区形成后并非持续稳定存在的,外力搅动(如台风等)以及水团混合等物理过程对其维持和发展都具有强烈的影响。例如,我们清楚的观测到2011年8月台风“梅花”过后长江口缺氧现象的重建过程,以及2011年10月在一股高温、低盐、高DO的水团侵入作用下缺氧区不断消亡的过程。 水体层化和呼吸作用是缺氧形成的重要条件,为了厘清缺氧形成过程中有氧呼吸作用的影响,我们以2011-8航次10m以深数据为例进行分析,结果表明,长江口中下层水体DIC增量(ΔDIC)/表观耗氧量(AOU)、AOU/溶解无机磷增量(ΔDIP)和N/P比值与Redfield比值相一致;而且2011-8重复断面(122o50′E)的调查结果显示,该断面中下层水体DO的下降速率与实测的CR速率相一致。这些结果都表明,夏季长江口缺氧区中下层水体,呼吸作用是DO降低,DIC增加的主要过程。呼吸作用,结合水体的层化作用,是夏季长江口缺氧形成的主要机制。 呼吸作用能够加剧水体pH下降。同样以2011-8数据为例,我们发现:呼吸作用使长江口中下层水体pH降低了0.01-0.31,相当于水体H+浓度增加了2.6-103.2%(60.7±22.1%)。在此基础上,我们进一步建立pH-DO模型,分析海水吸收人为CO2和呼吸作用对pHT下降的影响,结果表明:工业革命以来,海水对人为CO2的吸收已造成水体pHT下降约0.138,而至2100年,该过程将使水体pHT再下降0.230,在呼吸作用的作用下,在工业革命前、现在以及2100年,水体pHT最大可分别下降0.336、0.402和0.489。在未来高CO2条件下,呼吸作用将进一步加剧水体pHT的下降,造成该结果的主要原因是海水对人为CO2的吸收和呼吸作用过程使水体碳酸盐体系缓冲能力弱化。 温度的升高同样对水体pH有显著影响,温度升高能够降低pHinsitu(总氢离子标度,原位温度);但在未来海洋高CO2浓度下,温度变化本身的对pHinsitu影响会逐渐减弱。并且,随着温度的不断升高,呼吸作用过程所能引起的最大ΔpHinsitu将不断降低;如果考虑不同时期温度对呼吸速率的影响,并考虑水体停留时间、有机物供应等因素,那么,由于在工业革命前、现在和2100年,由于呼吸速率的不同,呼吸作用影响程度不同,造成的水体pHT降幅将分别为0.182、0.231和0.438,相比现在,在未来高温、高CO2条件下,呼吸作用过程将更加剧水体pHT的降低。另一方面,在大气CO2浓度不断升高和呼吸作用加剧的共同作用下,在未来2100年,长江口缺氧区,水体碳酸钙将处于不饱和状态。 而在法国Villefranche湾外Port-C时间连续站1年多的观测则表明:地中海弱光层水体,CR速率存在着显著的季节性变化,其变化范围为0.23-1.65μmolO2L-1day-1,相比于上层水体,该水体微生物群落活性并无显著差异,处于同样较活跃的状态,对水体碳循环影响显著。通过Spearman相关性分析和主因子分析则表明:水体层化和混合、原核生物丰度(PA)、病毒丰度(VA)以及透明胞外聚合颗粒物(TEP)浓度变化对CR季节性变化具有显著影响。 为研究OA对呼吸作用的影响,我们取Port-C站300m层水体进行了一系列受控酸化培养实验。短期培养实验(培养时间约为3d)结果表明:提高pCO2对BR具有一定的影响,但是影响程度并不十分显著,仅在一组短期培养实验5(STI-5)中发现提高pCO2对BR速率具有显著的促进作用。而在长期培养实验(LTI-2,培养时间约为60d)中,不同的pCO2处理组BR速率亦无显著性差异。但此影响仅限于中低强度的pCO2,当pCO2升高至3750ppm以上时,提高pCO2对BR速率具有显著的抑制作用。整体上,pCO2的提高,对PA和VA基本无影响,但该过程可能潜在改变病毒群落各组分的比例,而对病毒群落结构产生影响,并进而改变浮游原核生物群落的结构。此外,不论是在短期还是长期培养实验中,温度升高都具有很强的促进效应,温度升高对微生物群落结构和功能具有显著影响。在短期培养实验中,温度提高3.0oC,BR速率平均增加约1倍;而在长期培养实验中,在400和1000ppm下,T31时,温度提高3.0oC,呼吸速率可相应增加36%和17%;在T61时,该速率增长则为34%和24%。海洋酸化和温度升高对呼吸作用具有强烈的影响作用。Respiration and primary production are the two fundamental processes of the marine ecosystem metabolism. By respiration, marine microbes consume oxygen, decompose organic materials, and release carbon dioxide (CO2) and nutrients. In many coastal environments, intensified respiration has been shown to lead to the formation of hypoxia. While hypoxia develops, the released CO2 by aerobic respiration will further induce the acidification of the seawater. On the other hand, ocean acidification (OA) also has significant impact on respiration through changing the carbon consumption efficiency of microbial communities. Respiration and OA thus interplays, especially in the hypoxic zones. However, our understanding to such interplay remains limited. This dissertation chose the continental shelf of the East China Sea (ECS) and the areas off the Changjiang estuary as the main research areas and sought to investigate the evolution of the hypoxia and the role of the aerobic respiration in the development of hypoxias. Also examined was the seawater acidification induced by aerobic respiration in the hypoxic zones. A series of microcosm experiments were also carried out to assess the effect of OA on respiration. During the surveys carried out in June 2011, August 2009 and October 2011, the surface community respiration (CR) rates were in the ranges of 0.6-40.6 (mean ± SD: 10.2 ± 12.0), 0.3-28.1 (mean ± SD: 8.6 ± 7.7) and 0-10.0 (mean ± SD: 3.2 ± 2.5) μmol O2 L-1 day-1 respectively. More than 90% of these CR were attributed to phytoplankton and bacterioplankton respiration (BR). Among the measured CR, phytoplankton’s contribution was rather significant in the surface waters in the plume area with salinity ≦32.0, while the role of the bacterioplankton became important below the euphotic zone in the non-plume area (salinity > 32.0). Comparison with the primary production in the study areas revealed that most of the study areas off the Changjiang estuary were heterotrophic during summer and autumn except the nearshore areas adjacent to the Changjiang estuary during the survey in June 2011. To examine the evolution of hypoxia, six cruises were conducted off the Changjiang estuary. Clear temporal and spatial variations in DO, pHT (total scale, 25.0oC) and dissolved inorganic carbon (DIC) in the bottom water were observed; DIC addition and pHT drawdown were well associated with the DO decline. Three hypoxic zones were observed with their centers located at 122o 40′ E, 31o 30′ N; 123o E, 31o N and 123o 30′ E, 30o N in July, August and October 2011 respectively. In general, the hypoxia in the ECS began to develop in late spring and early summer, reached its intensive stage in August, was weakened in the autumn and finally disappeared in the winter. To better examine the role of aerobic respiration in the development of hypoxias, a three end-members model was adopted using the data collected from the cruise in August 2011. The ratios of apparent oxygen utilization (AOU) to the net accumulation of dissolved inorganic phosphate (△DIP) and AOU to the net accumulation of DIC (△DIC) were both well fitted to the Redfield ratios. Furthermore, during the repeated surveys along 122o 50′ E, the DO decline rate was much close to the average measured CR rate in the subsurface water. These results indicated that the aerobic respiration was the main process leading to the hypoxia. Furthermore, based on the measured CR rates off the Changjiang estuary, the time to form a hypoxic condition during the summer time was estimated as学位:理学博士院系专业:海洋与环境学院_环境科学学号:2262006015335

    The Empirical Study of Macroeconomic Policies in China

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    针对目前我国宏观经济政策的研究大多侧重于理论分析和作用路径分析的现状,本论文采用实证研究的方法系统检验了我国宏观经济政策的的目标、效应和传导机制。 本文得到的主要结论有: 1、我国的单位产出劳动成本对通货膨胀有显著的影响。在我国城市化进程中,大量农村剩余劳动力向城市转移,一定程度上形成了劳动力供给弹性无穷大的局面,这是我国劳动力产出份额较低并呈下降趋势的主要原因。随着劳动力供给局面的改变,劳动成本的上升将给通货膨胀带来持续的压力。因此宏观政策必须在控制通货膨胀和提高劳动收入之间进行权衡。 2、我国的通货膨胀率与经济增长率之间存在长期稳定的关系,长期而言,二者正相关。在严重的通货膨胀环境中...Present for most of our macroeconomic policy research focused on the role of theoretical analysis and path analysis. Therefore, the research objective of this article would be an analysis of macroeconomic policy to give an better explanation and policy recommendations of the relationship between macro-control targets and the effects of macroeconomic policies based on a series of empirical method...学位:经济学博士院系专业:经济学院财政金融系_金融学(含保险学)学号:B20024200

    Variable Structure Sliding Mode Control for PMSM Vector Control

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    将滑模变结构控制策略引入永磁同步电机矢量控制中,以提高永磁同步电机矢量控制系统的响应速度,增强其鲁棒性。叙述了滑模变结构的基本原理,给出了永磁同步电动机滑模变结构模型,推导了滑模变结构控制律,并分析了抖动产生原因及相应对策。仿真结果表明,该控制策略极大地改善了系统的动、静态性能,对系统参数和外部干扰表现出较强的鲁棒性,是永磁同步电机矢量控制中一种新颖的改进控制方式。A variable structure sliding mode(VSS) control strategy is proposed in this paper to improve the response speed and robustness associated with vector control of permanent magnet synchronous machine.This paper explains the basic theory of VSS and the model of VSS Control for PMSM in detail,derivates the Variable Structure Sliding Mode Control law,and analyses the reason and measure of wobble.Simulation results indicate that the control strategy has greatly improved the system dynamic and static performance and shows effectively robust to system parameters and disturbances and is a new improved control method for PMSM vector control

    Appl ica t ion of In tell igen t Themometer D s18b20 in M ult iple Tempera tureM ea suremen t

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    给出了总线上挂有多个D s18b20 的巡回测温的C51 编程实现。通用性好, 特别适合用在大范围环境温度检测 场合, 数据准确、可靠。最后给出笔者参与的一个应用项目

    Pathogenesis of herpes simplex keratitis

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    单纯疱疹病毒性角膜炎(HErPES SIMPlEX kErATITIS,HSk)是一种常见的眼部疾病,由单纯疱疹病毒(HErPES SIMPlEX VIruS,HSV)感染引起。人群中超过90%的人曾经感染过HSV。HSV可以在神经组织及角膜组织长期潜伏。在适宜的刺激下,如紫外线照射、发热、精神压力、高温、低温、手术等,病毒活化增殖导致HSk。HSV感染引起的免疫反应是造成角膜组织损害的主要机制。HSk的免疫反应主要是由Cd4+细胞介导的,而Cd8+细胞对病毒感染具有保护作用。Herpes simplex keratitis(HSK) is one of the most common ocular diseases,which is caused by Herpes simplex virus.More than 90% individuals have been infected with herpes simplex virus(HSV) in his lifetime.HSV establishes both neuronal latency and corneal latency.Stressful stimuli such as UV radiation,fever,stress,hypothermia,hyperthermia and surgical manipulation of the trigeminal ganglia can cause reactivation.The corneal lesions after HSV infection is mainly the result of the immunoreaction in which CD4+ cells appeared to be mediating the pathology,with CD8+ cells seemingly playing a protective role.国家自然科学基金(No.81160119); 广西自然科学基金(No.2012GXNSFAA053107); 广西高等学校立项科研项目(No.201204LX064)~
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