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指数分布利息力下年金的期望和方差
The Expectation and Variance of Annuity under Exponential Distributed Interest Force  [PDF]
周东琼, 章溢, 温利民
Statistics and Applications (SA) , 2013, DOI: 10.12677/SA.2013.24020
Abstract:
年金是指在一定期限内的系列现金流量。年金的现值与利率密切相关。在传统的精算理论中，在年金的计算中，常常假定利息率为已知的非随机变量，这主要是数学上处理的方便而假设的。然而，实际中的利息率与投资收益、汇率、金融市场等多种因素有关，假定利息率是随机变量更加合理。本文在利息力指数分布的模型子下，研究了各种固定年金和生存年金的期望和方差。
An annuity is a series of cash flow within a certain period of time. The present value of the annuity is closely related to interest rates. In the traditional actuarial theory, the interest rate is usually assumed to be fixed and known in advance in the calculation of the annuity. This assumption basically is mathematically treated easily and hypothetical. However, the actual interest rate is dependent on investment income, exchange rate, financial market and other factors. Therefore, it is more reasonable to assume that the interest rate is a random variable. In this paper, the interest force is assumed to be exponentially distributed, and correspondingly, the expectation and variance of the various fixed annuities and life annuities are hence derived.
指数-伽马模型下在险价值度量的贝叶斯估计
章溢,周东琼,温利民
应用概率统计 , 2015,
Abstract: VaR风险度量在金融、保险中有重要的应用.本文建立了贝叶斯模型,在某种损失函数下研究了VaR风险度量的贝叶斯估计.证明了指数-伽马分布下贝叶斯估计的强相合性和渐近正态性,最后利用数值模拟的方法验证了不同样本容量下估计的收敛速度.
卡亚抗营养因子研究及不同加工处理对氰苷含量的影响
周才琼,范东翠
- , 2010,
Abstract: 借助系统预实验初步判断引种资源卡亚可能含有的抗营养因子，并通过定量分析确定卡亚中主要抗营养成分及氰苷在不同加工处理时的变化。结果表明：卡亚鲜叶含生氰糖苷、生物碱和甾体皂甙，可能含有鞣质，氰苷是主要抗营养因子；蒸汽加热、鼓风干燥处理、微波处理及沸水焯烫均可降低氰苷含量，残留率分别为31.31%、40.69%、 3.74% 和2.17%。实验表明卡亚含有氰苷，微波处理和沸水焯烫可迅速降低氰苷含量，低于5mg/kg，达到安全食用标准要求
社会支持对卫校学生积极应对疫情的影响机制
Influence Mechanism of Social Support on Positive Coping Behaviors of Health School Student during the COVID-19 Prevention  [PDF]
时勘, 宋旭东, 李晓琼, 李秉哲, 周海明, 焦松明, 卢涛
Advances in Psychology (AP) , 2021, DOI: 10.12677/AP.2021.113084
Abstract:
为探讨在疫情下社会支持、自我效能和个体抗逆力对卫校学生积极应对行为的影响机制，本研究采用新冠疫情社会支持量表、积极应对行为量表、新冠疫情自我效能量表和个体抗逆力量表，对江西某卫生学校1050名学生进行了调查。结果发现，社会支持和卫校学生在疫情下的积极应对行为呈显著的正相关。在控制性别、年龄、学历后，社会支持、自我效能和个体抗逆力均对积极应对行为具有显著的直接正向预测作用(t = 7.53, p < 0.001; t = ？6.13, p < 0.001; t = 16.12, p < 0.001)，自我效能、个体抗逆力在社会支持和积极应对行为之间起部分中介作用。在新冠疫情防控常态化期间，要警惕自我效能的负向影响，需进一步发挥抗逆力的正向影响，并考虑与抗逆成长的核心胜任特征成长评估和培训工作结合起来，从而改善青少年学生群体在重大公共卫生突发事件的应急反应模式。
In order to explore the influence mechanism of social support, self-efficacy and individual resi-lience on health school students’ positive coping behaviors under epidemic situation, we use the COVID-19 social support scale, positive behavior questionnaire, coronavirus self-efficacy scale and resilience scale to investigate 1050 teachers and students in a health school in Jiangxi province. We found that there was a significant positive correlation between social support and health school student’s positive response to the epidemic. After controlling for gender, age and educational background, social support, self-efficacy and individual resilience all have significant direct positive predictive effects on positive coping behaviors (t = 7.53, p < 0.001; t = ？6.13, p < 0.001; t = 16.12, p < 0.001). Self-efficacy and individual resilience play a partial mediating role between social support and positive coping behaviors. During the normal period of COVID-19 prevention and control, we should be alert to the negative impact of self-efficacy and further exert the positive impact of resilience. What’s more, considering combining it with the core competency characteristics growth assessment for resilience to growth is also important to improve the emergency response mode of young people in major public health emergencies.
基于图像序列的虚拟场景重建和漫游
吴琼玉,周东翔,蔡宣平
中国图象图形学报 , 2006, DOI: 10.11834/jig.20060118
Abstract: 基于图像的建模和绘制方法与基于传统的几何绘制方法相比有很多优点,但是在场景几何参数未知的情况下,要实现单幅图片和图像序列的漫游,难度很大.TIP（tourintoapicture）技术使得在一幅图像中漫游成为可能.为了实现场景几何参数未知情况下的场景漫游,在对TIP技术进行扩展的基础上,提出了一种能够在未知视点路径的图像序列中实现场景漫游的方法.这种算法在相机未定标的情况下,不仅解决了图像序列建模和场景漫游过程中前后图像场景不能平滑过渡的问题,并且扩大了TIP中视线方向变化的动态范围,从而在保证图像质量的情况下,实现了由图像序列到场景的无限制漫游.实际图像序列的实验结果表明,该算法是有效的,具有实际应用价值.
响应面法优化微孔淀粉制备工艺
周琼,张博,王浩东,陈宗道,null
- , 2010,
Abstract: 通过单因素、部分因子、Box-Behnken 试验，确定最佳制备微孔淀粉的工艺参数。结果表明：反应温度51.92℃、反应时间13.15h、淀粉乳体积分数14.24%、酶用量4.20%、酶配比(m糖化酶:m淀粉酶)4:1、pH4.4 为最佳工艺参数，此时微孔淀粉的吸水率156.01%
基于ip应用的网络质量评价研究
周红琼,周宇,叶庆卫,王晓东？
计算机科学 , 2012,
Abstract: 将信息融合领域应用广泛的ibs证据理论引入网络评价领域。以网络应用为导向，分析选取待评价网络主要承载应用的kpi，使其作为指标级信息输入;采用ahp法进行基本概率赋值，建立一种互联网质量评价层次结构，利用两级的ibs结构进行证据融合，得到目标级网络质量评价结果。经计算可知，两级的ibs证据融合推理模型极大程度上消除了不确定性，具有很好的实践性。
水分胁迫对玉米苗期生长性状的影响
Effects of Water Stress on Growth Traits of Maize Seedling  [PDF]
高琼, 邹原东
Hans Journal of Agricultural Sciences (HJAS) , 2019, DOI: 10.12677/HJAS.2019.96071
Abstract:
通过观察玉米杂交种在干旱环境下的生长性状表现，用玉米幼苗期的萌发抗旱指数来评价玉米的抗旱性，为抗旱品种选育提供借鉴。本试验采用PEG-6000水溶液模拟干旱环境，比较4个玉米品种在幼苗期的发芽率、萌发性状的变化。研究表明，随着天数的增加，4个品种的发芽率都表现为先增加后降低，在4%~6%的PEG-6000水溶液浓度下玉米品种的发芽率高于其它浓度；TN1在干旱胁迫下种子萌发指数相对较高，从萌发抗旱指数的差异分析来看，TN1同NT2、TN3、TN4相比差异极显著(p < 0.01)。试验材料的萌发性状表现同抗旱指数差异性表现一致，可以用来鉴定玉米萌发期的抗旱性强弱。
The drought resistance of maize was evaluated by germination drought resistance index at seedling stage, which could be used for reference in breeding drought resistant varieties. In this experiment, PEG-6000 aqueous solution was used to simulate the drought environment to compare the germination rate and germination characteristics of four maize varieties in the seedling stage. The study showed that the germination rate of the four varieties increased first and then decreased with the increase of days. The germination rate of 4% - 6% PEG-6000 aqueous solution was higher than other concentrations. TN1 had higher germination drought-resistant index. From difference analysis of sprout index of drought resisting, the difference was extremely significant compared TN1 with NT2, TN3 and TN4 (p < 0.01). The germination traits of the test materials were consistent with the difference of drought resistance index, which could be used to identify the drought resistance of maize during germination.
STABILITY ANALYSIS ON THE HIGH SLOPES OF THREE-GORGES SHIPLOCK USING FLAC-3D
FLAC-3D 进行三峡船闸高边坡稳定分析
Kou Xiaodong,Zhou Weiyuan,Yang Ruoqiong,
寇晓东,周维垣,杨若琼
岩石力学与工程学报 , 2001,
Abstract: The theory background of FLAC 3D and its features are introduced firstly and then the analysis on the stresses, deformation and parameter sensitivity of the high slope of Three Gorges shiplock are presented.
在碱性溶液中Cu-Ni合金镀层钝化膜的半导体性能研究
吴红艳,王,毅,钟庆东,周琼宇,朱振宇,杜海龙
腐蚀科学与防护技术 , 2012,
Abstract: 用电化学方法测量Cu-Ni合金镀层在1mol/L的NaOH溶液中的Tafel、EIS和Mott-Schottky曲线,研究了镀层钝化膜的电化学性能,并借助点缺陷模型(PDM)计算了钝化膜的受主浓度、平带电位及阳离子空位扩散系数.结果表明Cu-Ni合金镀层表面钝化膜具有p型半导体性质.受主浓度和平带电位随成膜电位的负移而增大.随着合金镀层Cu含量的增加,受主浓度和钝化膜阻抗减小,钝化膜耐蚀性降低.不同Cu含量的Cu-Ni合金镀层阳极氧化后的钝化膜阳离子空位扩散系数为10-14cm2/s.
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