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将劳动力增长方程引入企业投资方程,以按劳动力计算的人均资产为状态变量,研究该方程的等价方程的解的存在唯一性,并讨论了科技进步对资产增加的重要作用. 相似文献
63.
Spectroscopy system based on a single quantum cascade laser for simultaneous detection of CO and CO_2
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A quantum cascade laser(QCL) based system for simultaneous detection of CO and CO_2 is developed.The QCL can scan over two neighboring CO(2055.40 cm~(-1)) and CO_2(2055.16 cm~(-1)) lines with a single current scan.The wavelength modulation spectroscopy( f = 20 k Hz) is utilized to enhance the signal-to-noise ratio.A white cell with an effective optical path length of 74 m is used.The calibration of the sensor is performed and minimum detection limits of 1.3 ppb(1 × 10~(-9))for CO and 0.44 ppm(1 × 10~(-6)) for CO_2 are achieved. 相似文献
64.
提出一个基于滤子技术的填充函数算法, 用于求解带箱式约束的非凸全局优化问题. 填充函数算法是求解全局优化问题的有效方法之一, 而滤子技术以其良好的数值效果广泛应用于局部优化算法中. 为优化填充函数方法, 应用滤子来监控迭代过程. 首先给出一个新的填充函数并讨论了其特性, 在此基础上提出了理论算法及算法性质. 最后列出数值实验结果以说明算法的有效性. 相似文献
65.
提出了一个任意初始点的广义梯度滤子方法. 该方法不使用罚函数以避免由此带来的缺陷并可以减少计算量. 方法的另一个特点是不因使用了滤子技术而使算法早熟或陷入循环. 算法对初始点没有要求并在比较合理的条件下具有全局收敛性. 相似文献
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Molecular dynamics (MD) simulation has become a powerful tool to investigate the structurefunction relationship of proteins and other biological macromolecules at atomic resolution and biologically relevant timescales. MD simulations often produce massive datasets containing millions of snapshots describing proteins in motion. Therefore, clustering algorithms have been in high demand to be developed and applied to classify these MD snapshots and gain biological insights. There mainly exist two categories of clustering algorithms that aim to group protein conformations into clusters based on the similarity of their shape (geometric clustering) and kinetics (kinetic clustering). In this paper, we review a series of frequently used clustering algorithms applied in MD simulations, including divisive algorithms, agglomerative algorithms (single-linkage, complete-linkage, average-linkage, centroid-linkage and ward-linkage), center-based algorithms (K-Means, K-Medoids, K-Centers, and APM), density-based algorithms (neighbor-based, DBSCAN, density-peaks, and Robust-DB), and spectral-based algorithms (PCCA and PCCA+). In particular, differences between geometric and kinetic clustering metrics will be discussed along with the performances of different clustering algorithms. We note that there does not exist a one-size-fits-all algorithm in the classification of MD datasets. For a specific application, the right choice of clustering algorithm should be based on the purpose of clustering, and the intrinsic properties of the MD conformational ensembles. Therefore, a main focus of our review is to describe the merits and limitations of each clustering algorithm. We expect that this review would be helpful to guide researchers to choose appropriate clustering algorithms for their own MD datasets. 相似文献
68.
A feasible and superlinear algorithm for inequality constrained minimization problems 总被引:1,自引:0,他引:1
1. IntroductionConsider the optimization problemmin {f(x): gi(x) 5 0, j E I; x E R"}, (l)where f(x), gi(x): Rad - R, j E I ~ {1, 2,...,m}.It is well known that one of the most effective methods to solve problem (1) is thesequential quadratic programming (i.e., SoP) (see [1--6]), due to its property of superlinearconvergence. Especially in recent years, in order to perfect SoP both in theory and application, there have many papers, such as [7--10], been published. These papers focus mainly… 相似文献
69.
以“美育”内涵中“培养发现美的能力”为契合点,借助大一新生在无机元素化学实验中发现美时获取的成就感,引导学生在追求“美丽”实验结果的过程中,自发地对基本操作进行训练和提高,由此发挥美育在无机化学实验教学过程中的迁移作用。以钴离子形成多色配合物为“点”,带动学生持续发现实验中更多的“美”,逐步培养细心、耐心和恒心的素养。同时,在新高考、新生源背景下,注重大一新生化学学习兴趣的提高,将直接影响到其对专业的认知及职业的认同,因而其积极作用是不容忽视且意义深远的。 相似文献
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