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Search Results: 1 - 10 of 99859 matches for " 赵雨晴 "
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科技型中小企业成长路径研究――一个理论分析框架的提出
,
科技进步与对策 , 2011,
Abstract: 受完美假设的制约,新古典理论体系内在地忽略了企业成长过程和其自身能力,也无法对经济系统的复杂性行为进行深入研究。因此,企业成长仍然是一个具有很强"黑箱性质"的问题,学术界对其内在成长规律的认识也相当匮乏。为增强理论模型对企业成长过程的解释力,将异质性资源这个笼统而抽象的概念具体为知识资本,内生于科技型中小企业的成长过程中,从概念层系、经济环境、行为假设等方面构建了一个完整的动态演化理论分析框架。企业成长知识资本分析框架理论范式
承压含水层应力场与井水位变化的数值模拟
Numerical Simulation of Stress Field Induced Groundwater Level Change in Confined Aquifer

,永红
- , 2017, DOI: 10.13209/j.0479-8023.2017.013
Abstract: 摘要 将含水层看成孔隙弹性介质, 建立二维承压含水层理想模型, 计算周围应力场变化引起的井水位变化的分布和量级, 讨论井水位突变的消散规律。根据消散过程, 用反褶积的方法, 从井水位数据计算周围应力应变场的变化, 并用数值方法和会理川06井的固体潮数据验证这种方法的可行性。应用数值模拟结果探讨同震井水位阶变的机制, 认为简单的孔隙弹性模型不能解释同震井水位变化特征。
Abstract The aquifer can be treated as poroelastic media in current research. An ideal 2D confined aquifer model was founded to calculate the response of the groundwater level to the variation of stress field. Then the dissipation law of abnormity of groundwater level was discussed. A deconvolution method to invert stress-strain field from groundwater level data when considering the dissipation process was also discussed. Results from forward calculation and earth tide data of Huili Chuan-06 well were analyzed to confirm the deconvolution method. At last, the mechanism of co-seismic step variation in groundwater level was analyzed. It was concluded that a simple poroelastic model cannot explain the amplitude of variation.
美国培育核心价值观的十大路径
Ten Paths of Cultivating Core Values of the United States
 [PDF]


Advances in Philosophy (ACPP) , 2015, DOI: 10.12677/ACPP.2015.43008
Abstract:
美国非常重视培育核心价值观,积累了丰富的经验,其基本做法是通过政府、政党、中介组织、学校、媒体、法律、宗教、实物、文化产业、高科技等途径、手段和方法进行直接或间接的灌输与渗透。系统梳理、理性分析、批判汲取美国培育核心价值观的实践路径,对于培育社会主义核心价值观具有重要参考意义和借鉴价值。
The United States attaches great importance to cultivate the core values, and they have accumu-lated a lot of experience. They take basic ways to cultivate core values by means to proceed inculcation and infiltration directly or indirectly, such as the government, political parties, intermediary organizations, schools, media, law, religion, physical, cultural industries, high-tech ways, and so on. The systematic, rational and critical analysis path of cultivating core values of America has important reference meaning and value on cultivating the socialism core values.
共沉淀法制备LaFeXCo1-XO3钙钛矿的研究
Preparation of LaFeXCo1-XO3 Perovskite by Coprecipitation
 [PDF]

, 石凯
Open Journal of Nature Science (OJNS) , 2016, DOI: 10.12677/OJNS.2016.44046
Abstract:
以La(NO3)36H2O、Co(NO3)36H2O和Fe(NO3)39H2O为原料,用共沉淀法对制备LaFexCo1?xO3 (x = 0.2, 0.5, 0.8)钙钛矿进行研究。热重–差示量热分析(TG-DSC)和X射线衍射(XRD)分析表明,合成LaFexCo1?xO3钙钛矿过程有四段失重,分别在110℃之前、150℃~220℃、300℃~500℃和700℃~780℃;经过700℃~800℃煅烧后有钙钛矿形成,之后随煅烧温度提高,钙钛矿生成量逐渐增加,晶粒尺寸也缓慢增加,煅烧温度为1000℃时获得钙钛矿的量最多,但是与800℃和900℃煅烧后形成钙钛矿相比,其晶粒尺寸增加较多;随着Fe取代Co的量增加,形成钙钛矿尺寸晶粒尺寸逐渐降低。
Preparation of LaFexCo1?xO3 (x = 0.2, 0.5, 0.8) perovskite by coprecipitation using La(NO3)36H2O, Co(NO3)36H2O和Fe(NO3)39H2O and Fe(NO3)39H2O as raw materials was researched. The phenomena observed were characterized using Thermogravimetry-Differential Scanning Calorimetric (TG-DSC) and X- ray diffraction (XRD). Results showed that process of preparing LaFexCo1?xO3 perovskite appeared four period of weight loss at less than 110?C, 150?C - 220?C, 300?C - 500?C and 700?C - 780?C, respectively. The sample calcined at 700?C - 800?C has already formed perovskite, then amount of forming perovsktie and the grain size of perovskite increase gradually with the calcination temperature. When calcination temperature is at 1000?C, the most amount of perovskite is gained, but the grain size increases more than that of perovskite calcined at 800?C and 900?C. With the increase of substitute Fe for Co, perovskite particle size is gradually reduced.
黄河源区近60a气候变化特征及暖湿化分析
珍伟,梁四海,万力,,余张琛
人民黄河 , 2014,
Abstract: ?为揭示黄河源区气候变化特征与趋势,利用1953—2012年玛多地区年平均气温和年降水量,采用线性趋势分析、mann-kendall突变检验和morlet小波变换等方法,对玛多地区的气候变化特征进行了分析。结果表明:玛多地区年平均气温呈显著升高趋势,倾向率为0.289℃/10a,1997年发生了由低温向高温的突变;年降水量呈增加趋势,倾向率为10.21mm/10a,降水量由少到多的突变发生在2003年;玛多地区年平均气温的第一主周期为15a,此外还有6a、29a的变换周期;年降水量的第一主周期为27a,此外还有12a、5a的变换周期。
黄河源湖间冻土区温度场与活动层厚度的变化
,梁四海,洪涛,万力,珍伟
人民黄河 , 2015,
Abstract: ?采用黄河源区2012年8月—2013年7月的日尺度地温观测数据,运用含有水相变化的地下水运动的水-热耦合原理,利用sutra-ice软件建立了模拟冻土在冻融过程中温度场分布的二维模型,在校正模型参数的基础上,预测了未来情景下黄河源区多年冻土活动层厚度的变化情况。结果表明:黄河源区冻土活动层浅层地温最高为14℃,最低为-9.5℃,分别出现在7月、1月;土壤温度变幅从浅层20cm到深层150cm不断减小且存在滞后现象,与20cm处的冻结日期相比,50、90、120、150cm处分别滞后9、24、41、51d;在假定升温率为0.04℃/a的情景下,黄河源区冻土活动层厚度由3.90m增加到20a后的5.86m,增加率为9.8cm/a。
基于金、银溶胶的表面增强拉曼光谱法测定苹果中马拉硫磷含量对比研究
刘翠玲,,孙晓荣,
食品科学 , 2014,
Abstract: ?使用共焦显微拉曼光谱仪,结合表面增强拉曼散射技术,将含有农药马拉硫磷的苹果汁样本进行一定的前处理后,分别采集其基于金、银溶胶的表面增强拉曼光谱,结合逐步多元线性回归方法对两种光谱分别进行数学建模分析。结果表明,在0.01~0.5mg/kg的线性范围内,基于金溶胶所建立的模型相关系数(r2)为0.9996,校正标准差为0.00186mg/kg,真实值与拟合值差异最大不超过0.003mg/kg,而基于银溶胶所建立的模型相关系数(r2)为1,校正标准差为0.00078mg/kg,真实值与拟合值差异最大不超过0.0012mg/kg,预测标准差分别为0.213mg/kg和0.146mg/kg,银溶胶效果优于金溶胶。
基础软件平台质量评估
,同?,高静?,接卉?,金茂忠?
软件学报 , 2009,
Abstract: 关于软件质量模型和软件质量评估模型的研究,一直是软件质量保障和评估领域的研究热点,国内外在这两方面进行了大量的研究,并取得了一定的研究成果.近年来,以操作系统为核心的基础软件呈平台化、体系化的发展趋势,基础软件平台的质量评估成为亟待解决的问题.在总结、分析软件质量模型、软件质量评估模型研究发展现状的基础上,重点归纳和描绘了基础软件平台的质量评估发展历程,并简要探讨了基础软件平台质量评估研究的发展方向,力求为展开基础软件平台的质量评估建立良好的基础.
基于纳米金催化的血清尿酸纸芯片的构建及应用
甜甜,,张敏,王月荣,章弘扬,胡坪
- , 2016,
Abstract: 摘要 建立了一种以纸芯片为平台,利用纳米金(AuNPs)的过氧化物模拟酶特性对血清中尿酸(UA)含量进行快速检测的方法.在改装的中性笔中灌注疏水性材料溶液,直接在滤纸上绘制所需要的图案,经干燥后形成纸芯片.将纳米金、四甲基联苯胺(TMB)和H2O2的混合液依次滴加于纸芯片检测区域,无色的TMB被氧化成蓝色,然后将待测样品滴加于蓝色区域,氧化态TMB被还原为无色,根据手机相机记录的检测区域灰度值计算试样中尿酸的浓度.实验优化了纳米金在纸芯片上的用量、反应时间和反应温度等参数,在最优实验条件下,检测尿酸的线性范围为10.6~125 mg/L,检出限为4.64 mg/L,加样回收率为94.8%~108.5%.该方法选择性良好,可用于测定血清样品中尿酸的含量
基于正弦图平移匹配的投影旋转中心校正
Correction of the projection center of rotation based on the sinogram using translation matching method

,,丛长虹,冀东江,秦莉莉,陈晓冬,胡春红
- , 2018, DOI: 10.7507/1001-5515.201707065
Abstract: 投影旋转中心(COR)精准定位是确保计算机断层成像(CT)重建图像质量的关键要素,经典的互相关匹配算法在投影角度为 0~180° 时难以满足高质量 CT 成像要求,需进行改进创新。本文根据正弦图上 0° 与 180° 投影数据翻转后有对应性的特点提出基于这两行数据平移匹配的 COR 校正算法,该算法利用 OTSU 进行阈值分割以减少背景噪声影响,通过 L1 范数量化 COR 最小偏移得到准确校正值后进行 CT 重建。分别采用加入随机梯度噪声和高斯噪声的 Sheep-Logan 模型和雄性 SD 大鼠样本的同质肝脏与异质牙齿图像验证新算法的有效性,并将新算法与互相关匹配算法做性能对比。结果表明:新算法运算量少、简便快速且具有良好的抗噪鲁棒性,校正精度高(稀疏采样投影数据在 10%~50% 时也能很好地校正 COR 值),CT 重建图像质量有显著改进,效果优于互相关算法。
The accurate position of the center of rotation (COR) is a key factor to ensure the quality of computed tomography (CT) reconstructed images. The classic cross-correlation matching algorithm can not satisfy the requirements of high-quality CT imaging when the projection angle is 0 and 180°, and thus needs to be improved and innovated. In this study, considering the symmetric characteristic of the 0° and flipped 180° projection data in sinogram, a novel COR correction algorithm based on the translation and match of the 0° and 180° projection data was proposed. The OTSU method was applied to reduce noise on the background, and the minimum offset of COR was quantified using the L1-norm, and then a precise COR was obtained for the image correction and reconstruction. The Sheep-Logan simulation model with random gradients and Gaussian noise and the real male SD rats samples which contained the heterogenous tooth image and the homogenous liver image, were adopted to verify the performance of the new algorithm and the cross-correlation matching algorithm. The results show that the proposed algorithm has better robustness and higher accuracy of the correction (when the sampled data is from 10% to 50% of the full projection data, the COR value can still be measured accurately using the proposed algorithm) with less computational burden compared with the cross-correlation matching algorithm, and it is able to significantly improve the quality of the reconstructed images.
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