87 research outputs found
Approach and Methods of Marine Ecological Risk Assessment for radioactive Accident
近年来,随着核电事业发展迅速,海洋放射性污染压力激增。沿海地区核电站的大量建设将给海岸带地区带来极大的风险隐患,放射物质的事故性污染将成为海洋环境一个重要的问题。目前,海洋环境放射性风险评估、管理技术、核事故应急处理等方面的研究仍然较为薄弱,开展放射性污染事故的海洋生态风险评价技术方法研究有助于了解事故的影响范围和危害程度,为海洋与海岸带环境管理提供科学决策依据,以便采取相应措施减缓影响,维护海洋生态系统健康与安全。 本论文梳理总结了当前国内外海洋放射性污染生态风险评价的相关理论、技术路线与方法,系统构建了放射性污染事故的海洋生态风险评价的技术方法体系,并将构建的技术方法体系应用于案例研究中...The marine ecological risk assessment (ERA) of radioactive accident is a powerful technical and analytical tool for analyzing the possibility of coursing the risk and harmful effects on organisms, populations and communities by radioactive pollution in marine environment. With the rapid development of nuclear power plants in the coastal areas of international and China, the accidents of radioactiv...学位:理学硕士院系专业:海洋与海岸带发展研究院_海洋事务学号:3042014115165
Research on FM-DCSK Based Chaotic Communication System
随着科技的日新月异和飞速发展,无线通信和移动通信给人们日常生活带来的便利性,使它受到日益广泛的青睐和应用。然而以无线电磁波为媒介传输信号的通信系统,都不可避免地会遭受到各种衰落,尤其多径衰落的严重损害。传统通信借助于rake接收等补偿技术来对抗信道衰落,它需要对信道环境有一个比较准确的估计,这并不是容易精确做到的。混沌通信,即混沌调制解调(FM-DCSK),无需知道信道参数,从一个全新的角度,为解决多径衰落问题提供了一种简单易行的思路和方法,受到了业界特别的关注。混沌通信,不同于传统通信的地方就在于调制方案采用的是混沌调制。而混沌调制和传统调制最大的区别就在于,混沌调制的载波,采用的是非周期的...With the fast development of science and technology, the convenience of wireless and mobile communication makes it more appealing and widely applied. However they are inevitably impaired by fading especially multipath fading through wireless radio transmitting signals. In the conventional communication, compensative techniques like rake reception are introduced to resist such fading. The estimatio...学位:工学硕士院系专业:计算机与信息工程学院电子工程系_通信与信息系统学号:20033003
Design of Performance Appraisal System for Salesman of Application Software Corporation
只要把产品生产出来并不断降低生产成本,从而为市场提供有竞争力的价格的销售模式已经不被大多数人所接受。在激烈的市场竞争中如何更好地发现客户的需求,引导客户发现自己的需求,并如何将产品高质量地销售给客户已经成为各行各业特别是应用软件行业遵循的销售模式。 应用软件销售人员在这种销售模式中担负着重大的作用。如何有效地激励销售人员,提高销售人员积极性和销售队伍高效率工作是保证销售人员能够担负这种重大作用的有力保障。而我国应用软件行业起步较晚,都是新兴的企业,缺乏系统性的销售人员绩效管理经验,普遍存在重视结果忽视过程,只有考评缺乏计划和反馈等现象。另外,由于应用软件行业发展较晚,整个行业缺乏优秀的销售人...Such sale-modes as provide the production, reduce cost continually, and provide the competition price for market could not be accepted by most people. How to find the customers’ demands and how to guide the customers to find demands themselves, and how to sale the productions high-qualitative to customers already become the most popular sale-modes be accept by the different trade, especially the A...学位:工商管理硕士院系专业:管理学院工商管理教育中心(MBA中心)_工商管理硕士(MBA)学号:20041512
合同解除标的理论之反思与重构
传统理论认为合同解除的标的是有效成立的合同,与合同解除权以及其他合同救济手段的存在根据相矛盾,从而致使合同解除制度陷入逻辑困境。合同解除的标的应当重构为基础性合同权利义务关系,将救济性合同权利义务关系排除在外。同时,该解除针对的并非合同关系本身,乃是合同关系之效力
Numerical simulation of natural convection in the transient gas-liquid unsteady absorption process
传质过程中液相密度变化导致的自然对流,改变了液相流动状态,对传质有着较大的影响。利用纹影仪光学方法,获得了乙醇吸收CO2过程中自然对流的纹影图像;并通过吸收传质流体CFD模型,应用有限元方法对气液吸收过程中出现的自然对流发生过程进行了数值计算,得到了液相自然对流发生时的非稳态流场分布和浓度分布信息。分析结果表明传质过程中当自然对流发生后,促进了液相表面更新,加强了传质效果,在考察相际传质过程时,应充分考虑自然对流对传质速率的影响。The natural convection occurred in mass transfer process due to change of liquid-phase density gradient usually induces a higher mass transfer rate.By means of the Schlieren technique,Schlieren images of the natural convection were taken in CO_2-ethanol absorption system.Unsteady flow and concentration fields in the liquid phase of a gas-liquid contacting system were simulated to show the natural convection by utilizing the finite-element CFD method.According to the simulated and the experimental results,the influence of the natural convection on mass transfer was analyzed qualitatively.The result shows that the natural convection can facilitate the renewal of the surface and the mass transfer process.So the influence of natural convection on mass transfer should be fully considered in the investigation of interfacial mass transfer.国家自然科学基金资助项目(20606027);; 厦门大学科技创新工程基金资助项目(XDKJCX20041004
Research on the Clinical Pathway PDCA Continuous Improvement System Based on the Theory of Feedback Closed-loop Control System
运用控制论方法,将控制理论领域反馈的闭环控制法、管理学的PDCA循环等方法运用于信息系统的整合建设,建立电子病历一电子医嘱一临床路径一医院管理信息系统的“全闭环”临床路径执行和反馈体系,建立了疾病诊疗规范制定、临床操作服务、过程质量监管三位一体的医疗服务安全质量监测与持续改进闭环体系,临床路径信息管理平台对加强医疗服务安全动态监管,促进科学化、精细化、专业化管理,改善服务水平,提高效率具有不可或缺的重要作用。With the method of control theory, the feedback closed loop control method in the field of control theory, PDCA circulation of management and other methods are applied to the integrative construction of information system. The "closed loop" clinical pathway implementation and feedback system of electronic medical records-electronic medical advice-clinical pathway- hospital management information system is established. The medical service safety quality monitoring and continuous improvement closed-loop system integrating disease diagnosis and treatment specification formulation, clinical operation service and process quality supervision is set up. The clinical path information management platform has an indispensable important role on strengthening the dynamic supervision of medical service security, promoting scientific, refined and professional management, and improving the service level and eficiency.国家自然科学基金面上项目一大数据驱动的抗菌药物使用与管理决策优化研究(编号:71672160
Shadowg raph observat ion on interfacial turbulence phenomena in gas-liquid mass transfer
联系人及第一作者: 沙勇( 1971- ) , 男, 博士, 副教授。[中文文摘]引言在相际质量传递过程中,界面处液体物化性质由于物质传递发生改变,如产生密度梯度和界面张力梯度,使界面流体发生流动的现象即为界面湍动。通常由界面处流体密度梯度引发的界面湍动称为Rayleigh-Bénard对流,而由界面表面张力梯度引发的界面湍动,称为Marangoni对流[1]。由于传质过程中发生的界面湍动在临近界面处发生,其浓度场和速度场难以测量,目前多利用纹影法、投影法、干涉法等光学测试手段,对其湍动形态进行观察,为了解界面湍动提供直接视觉证据。利用蒸发、吸收、解吸、萃取等传质手段,不同的研究者对界面湍动进行了直接光学观察,考察了不同传质条件下的界面湍动结构,获取的形态众多,结构复杂[2-7]。对于气-液界面传质导致的界面湍动,其光学观察多集中在研究界面平面内出现的细胞形、六边形、滚筒形等规则或不规则形态,通常为湍动充分发展后的形态,尺度偏大[6-9],而对于实际应用中更重要的界面湍动向主体相渗透的时空观察,十分匮乏,尚需大量设计精巧的实验以揭示其内在的规律。传质过程中产生的界面湍动为强非线性传质流动耦合现象,是非线性理论良好的研究对象[10],并且界面湍动促进了流体表面更新,可对宏观传质设备传质产生显著影响[11],对其的深入研究有着理论和实际上的需要。
本文利用放大界面区域的投影法, 观察有机溶剂水溶液挥发过程中,由界面向液相主体渗透的界面湍动结构, 获取直接视觉资料。
[英文文摘]In gas-liquid mass transfer processes,interfacial turbulence may
occur due to the surface tension gradient and the density gradient produced by mass transfer near the interface.The interfacial turbulence can enhance the mass transfer since it intensifies the movement of interfacial fluid.By means of the shadowgraph optical method,the interfacial turbulence patterns vertical to the interface were observed directly in the volatilization process of binary systems.The images of the amplified interfacial turbule showed the variation of concent ration and the fluid movement under the interface. Two patterns of interfacial turbulence were
observed in the experiments: plume and
vortex.With the plume, the
interfacial fluid moved slowly and penet rated the liquid deeply.With the vortex, the inter facial turbulence occur red in the vicinity of the liquid interface and the
fluid moves quite fast. A qualitative analysis was carried out based on the mechanism of Rayleigh-Bénard convection induced by density gradient and Marangoni convection induced by surface tension gradient.国家自然科学基金项目( 20606027)
中药保留灌肠治疗溃疡性结肠炎疗效的荟萃分析
目的:系统评价中药保留灌肠治疗溃疡性结肠炎(ulcerative colitis,UC)的有效性和安全性。方法:检索CochraneLibrary、PubMed、中国期刊全文数据库(CNKI)、中国生物医学文献数据库(CBM)、万方数据库(Wanfang Data)、中文科技期刊全文数据库(VIP)建库至2017年7月的所有文献。按照Cochrane系统评价方法查找中药保留灌肠治疗UC的临床随机对照试验(RCTs),进行数据提取和质量评价后,采用RevMan 5.3软件进行荟萃(meta)分析。结果:共纳入36篇文献。Meta分析结果显示:治疗组的总有效率优于对照组[RR=1.20,95%CI(1.15,1.25),P<0.000 01];治疗后治疗组中医证候积分低于对照组[SMD=-1.55,95%CI(-2.03,-1.07),P<0.000 01];治疗后治疗组内镜积分低于对照组[SMD=-1.63,95%CI(-2.45,-0.81),P<0.000 1];治疗组复发率低于对照组[RR=0.36,95%CI(0.25,0.52),P<0.000 01];治疗组药品不良反应(ADRs)发生率低于对照组[RR=0.23,95%CI(0.12,0.44),P<0.000 1]。结论:中药保留灌肠治疗可以提高UC的总有效率,减轻相关症状,同时有效降低UC的复发率,减少ADRs发生率。解放军第一七五医院2016年青年苗圃课题(16Y025
凡口铅锌矿湿地处理系统的土壤原生动物
20 0 1年 12月 ,在广东省韶关市凡口铅锌矿湿地处理系统中采集土壤样品 ,采用Singh和Stout的培养法对土样中的原生动物进行定性、定量研究。共发现原生动物 4 2种 ,对照区和湿地每克风干土壤中原生动物的平均丰度分别为 2 377和 113,三大类土壤原生动物丰度中鞭毛虫占优势 ,多于纤毛虫和肉足虫。通过原生动物种类、丰度与土壤理化参数的统计分析说明铅锌尾矿对土壤原生动物群落的危害极大。通过土壤原生动物丰度和物种相似性聚类分析结果反映出正在使用的湿地 3土壤受污染严重 ,已停止使用的湿地 1
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