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贵州基础设施资本存量与经济增长的关系研究
The Research of Guizhou Infrastructure Capital and Economic Growth
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刘欢
Service Science and Management (SSEM) , 2012, DOI: 10.12677/SSEM.2012.12005
Abstract:

  要:基础设施是国民经济赖以发展的基础。本文通过永续盘存法估计了贵州1993年到2010年的基础设施资本存量,并将估计出的基础设施资本存量与贵州经济增长指标进行相关分析。从而证明基础设施的增加或改善对贵州的经济发展有积极地促进作用。

Abstract: The infrastructure is the foundation of the national economy development. This article estimates the infrastructure capital stock of Guizhou in 1993 to 2010 through the perpetual inventory method, and will estimate the related analysis between the infrastructure of the capital stock and Guizhou economic growth indexes. It is proved that increasing or improving infrastructure has actively promoted role on the economic development in Guizhou.

 

基于SVAR模型研究实际利率对我国A股市场的影响
Based on SVAR Model to Research the Actual Interest Rate in the Influence of the A Share Market
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刘欢
Advances in Applied Mathematics (AAM) , 2012, DOI: 10.12677/AAM.2012.11005
Abstract: 股票市场的变化受很多个因素影响,其中市场利率的变动和也是影响股票市场变化的因素。本文选取SVAR模型对中国A股市场2001~2011年的股票价格与成交量及实际利率变动之间的关系进行实证分析。研究表明:实际利率变化对我国股市波动性存在影响,但这种影响很微弱;实际利率变化与股市波动性的关系为负。
There are many factors affect the change of the stock market, and market interest rate movements is also one of the stock market change factors. This paper selects SVAR model to the A share market 2001-2011 years of stock price and volume, and the actual interest rate changes the relationship between the empirical analysis. Research shows that: The actual interest rate changes of Chinese stock market volatility influence existence, but the effect is very weak; The actual interest rate changes and stock market volatility of negative relationship.
金纹细蛾及其寄生蜂种群动态的模糊聚类分析
刘欢
河南农业科学 , 2015,
Abstract: 金纹细蛾(LithocolletisringoniellaMatsumura)是我国苹果产区的重要潜叶害虫,为了利用寄生蜂开展苹果园金纹细蛾的生物防治,调查了金纹细蛾及其寄生蜂发生的种群动态,并对两者种群动态进行了模糊聚类分析。结果表明:金纹细蛾对苹果的危害时间较长,始发生于6月初,并持续危害到10月底;7月中旬至9月中旬是金纹细蛾发生高峰期,存在明显的世代重叠现象。寄生蜂始发期晚于金纹细蛾,7月和8月是寄生蜂的发生高峰期。10月后金纹细蛾幼虫和寄生蜂的发生量均逐渐下降。金纹细蛾种群的22次调查结果可以聚为6类,λ=0.968;其寄生蜂的调查结果聚为4类,λ=0.982。聚类结果表明了苹果园中金纹细蛾及其寄生蜂种群动态随季节变化的差异,同时反映了金纹细蛾的种群消长与其寄生蜂的数量密切相关,寄生蜂是抑制苹果园金纹细蛾种群增长的主要因素之一。
鲫鱼新鲜度近红外定量预测模型的建立
刘欢
- , 2015, DOI: 10.13982/j.mfst.1673-9078.2015.7.028
Abstract: 为实现鲫鱼新鲜度的快速测定,本文基于近红外漫反射光谱定量分析技术和化学计量学方法,采集了144个鲫鱼鱼肉样品在1000~1799 nm范围内的光谱数据,测定了鲫鱼样品的pH、TVB-N含量、TBA含量和K值四种新鲜度指标;在确定近红外光谱数据最佳预处理方法和适宜波段的基础上,分别采用偏最小二乘法、主成分分析和BP 人工神经网络技术、偏最小二乘法和BP 人工神经网络技术建立了鲫鱼新鲜度定量预测模型。结果表明,鲫鱼样品四种指标数据范围均较大,可满足建模要求。以pH为鲜度指标时,采用偏最小二乘法和BP 人工神经网络技术建立的模型最好,其定标相关系数为0.9945;以TVB-N、TBA和K值为鲜度指标时,采用偏最小二乘法建立的模型最好,其定标相关系数分别为0.9857、0.9985和0.9952。建立的四种鲜度指标定量模型均具有较好的预测能力。
To rapidly determine the freshness of crucian carp (Carassius auratus), near-infrared (NIR) diffuse reflectance spectroscopy- based quantitative analysis coupled with chemometric methods was used to collect spectral data in the range of 1000~1799 nm for 144 carp samples. Freshness quality indexes including pH, total volatile basic nitrogen (TVB-N) content, the thiobarbituric acid (TBA) value, and the K value were measured for all samples. After the optimum spectral pretreatment method and suitable spectra bands were determined, quantitative prediction models for crucian carp freshness were established using partial least squares (PLS) regression, principal component analysis (PCA) combined with back propagation artificial neural network (BP-ANN), and PLS combined with BP-ANN. The ranges of the four indicator values for crucian carp samples were wide and met the assumptionss for modeling. When pH was used as the freshness indicator, the prediction model developed using PLS combined with BP-ANN was the best, and the correlation coefficient was 0.9945. When the TVB-N content, TBA value, and K value were used as freshness indicators, PLS prediction models were the best, and the corresponding correlation coefficients were 0.9857, 0.9985, and 0.9952, respectively. The established quantitative models for the four freshness indicators all had strong prediction capabilities.
批判性思维研究热点知识图谱
The Mapping Knowledge Domains Based on the Hotspots Research of Critical Thinking in China
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刘欢, 胡瑜
Advances in Psychology (AP) , 2014, DOI: 10.12677/AP.2014.46111
Abstract:
为了了解国内近几年批判性思维研究的重点和热点,本研究采用Bicomb软件和SPSS软件对从中国知网中标准化查询的2010~2014年的314篇文献分析绘制了批判性思维研究的知识图谱。结果表明,我国批判性思维研究热点主要围绕两大主线和三个领域展开。两大主线为:批判性思维培养和教学的研究,方法和内容的研究;三大领域包括:批判性思维的核心构成和培养;批判性思维的教育教学策略以及批判性思维的教学内容和教育改革。
In order to understand the domestic research hotspots on critical thinking in recent years, this study used the software of Bicomb and SPSS analyzing 314 papers from 2010 to 2014 which were selected from CNKI to draw critical thinking knowledge map. The results showed that our critical thinking research focused mainly on two main lines and three areas. Two main lines were: research on training and teaching of critical thinking as well as methods and contents; three areas include: core structure and culture of critical thinking, teaching strategies of critical thinking, and education content and reform of critical thinking.
基于SVAR模型研究环境污染与经济增长的关系
Research of the Relationship between Environmental Pollution and Economic Growth Based on SVAR Model
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刘欢, 方巧, 王双
Business and Globalization (BGlo) , 2013, DOI: 10.12677/BGlo.2013.12008
Abstract:
本文选取了1997~2010年全国工业的环境及经济数据,建立了工业废水、废气SO2与工业GDP的计量模型,基于结构向量自回归(SVAR)模型分析了变量之间的相互影响关系,结果显示环境因素对经济因素有长期影响。
This paper selected the data of country’s industrial environment and economic from 1997 to 2010, and the measurement model of industrial waste water, waste gas SO2 and industrial GDP was established. Based on SVAR (Structural Vector Autoregression) model, the impact of relationships between variables was analyzed, and the results showed that environmental factors had long-term effects on economic factors.
失禁性皮炎护理研究新进展
刘欢,宁宁
华西医学 , 2013, DOI: 10.7507/1002-0179.20130351
Abstract: 失禁性皮炎是大小便失禁患者的常见问题,不仅给患者带来痛苦,而且还增加了护理负担。文章拟通过对失禁性皮炎的定义、病因、发病机制、并发症、流行病学状况、评估干预工具及护理措施等方面的综述,旨在为临床处理失禁性皮炎提供科学依据。
供水管网微观水力模型简化技术研究
金溪,刘欢
武汉理工大学学报 , 2010,
Abstract: ?针对目前管网微观水力模型简化技术无法自动实现或简化计算目标单一等问题,提出了“按指定精度简化,枝状管简化,同水流方向、同属性串连管道简化”的方法。达到了精简管段、节点,同时最大限度保持简化前后模型平差结果一致性的目的。在节省管网水力平差计算时间的同时又很好的保存了原始管网的拓扑信息,使得简化后模型仍然具有微观模型的特性,可以应用于管网优化改造、优化调度等优化计算。
基于丁克问题的人口结构预测
Research of the Population Structure Prediction Based on Dink Problem
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刘欢, 方巧, 张昆鹏
Aging Research (AR) , 2014, DOI: 10.12677/ar.2014.11002
Abstract:
人口的增长是引起世界各国普遍关注的问题。随着社会的发展,科技的进步,人们的生活节奏在逐步加快,人才之间的竞争也在愈演愈烈,这些使得越来越多的人不愿意在业余时间为子女操心操劳,而要集中精力为自身的存在与发展拼搏,加之,养育孩子的经济负担越来越重,所以“丁克”家庭的数目也越来越多。因此许多学者担心:丁克家庭的大量出现,加剧了人口老龄化问题。本文首先采用一元回归对丁克人口进行预测,然后使用预测的丁克数据运用人口移算的方法对总人口进行预测,并分析人口结构,认为我国老龄化现象日益明显。
The population growth is causing widespread concern around the world. With social development and technological advances, people gradually accelerate pace of life, and talent competition is becoming intensively, which makes more and more people not willing to worry about their children in their spare time, but to concentrate on their own existence and development. In addition, the economic burden of raising a child is getting heavier and heavier, so the number of “DINK” family is also increasing. Many scholars are worried that “DINK” families have exacerbated the aging of population. First this paper uses simple regression to predict the population of dink. Based on the predicted dink data, we use the method of demographic shift operator to predict the total population and analyze the demographic structure, which shows that the aging phenomenon has become increasingly evident.
河口湍流数据现场采集和后处理
刘欢,吴超羽
海洋工程 , 2011,
Abstract: 利用声学多普勒流速仪ADV,在珠江河口崖门底边界进行了一个潮周期的湍流观测,并选取了急流和憩流两个典型时刻对数据进行后处理分析。后处理方法包括信号检查、过滤和去噪,每个步骤都包含无效数据的剔除和替换。结果表明,后处理对平均流速影响不大,但会显著改变脉动流速统计分布特性。对于河口非定常流动,未经处理的原始数据不适宜用于分析湍流特征量。
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