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Search Results: 1 - 10 of 28817 matches for " Xiaomin Sun "
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Construction and Validation of Self-Management Scale for Undergraduate Students  [PDF]
Gang Xue, Xiaomin Sun
Creative Education (CE) , 2011, DOI: 10.4236/ce.2011.22020
Abstract: This study developed a scale to assess undergraduate students’ self-management ability in daily life. Forty items about self-management on time, goal, emotions and personal relationships were generated for the draft scale. Content review panel deleted seven items. In Study 1, 522 Chinese undergraduate students took the test. Exploratory factor analysis and item analysis on the first half 261 cases deleted 6 items. Confirmatory factor analysis further revised the model and resulted in a two-factor Self-Management Scale, consisting of 21 items. Cross-validation on the second half 261 cases also verified the scale’s structural validity. In Study 2, responses from 374 undergraduate students were used to examine the reliability and criterion-related validity of the scale. The internal consistency reliability of the scale was 0.86. Relationship management showed good criterion-related validity, while the validity of performance management needs further examination.
Classification of a Course Deduction Teachings Innovation  [PDF]
Haozhang Sun, Xiaomin Ji, Feng Wang
Creative Education (CE) , 2012, DOI: 10.4236/ce.2012.37B029
Abstract:

In this paper, folk art class, for example,Clarify in teaching should be based on the course (folk art) in a form for the foundation, working people's living and production based on the main line of folk art forms of the associated property, are classified teaching point of view, examples focus on respect to comply with the regulatory class method, the habits of civil labor, the linkages between the various forms of folk art and the common features of the classification of ideas, as well as the form of derivatives, function approximation, the process of convergence classified. I hope a positive reference value for the improvement of education and teaching in the classification of cognitive and curriculum pedagogy.

Riemannian Gradient Algorithm for the Numerical Solution of Linear Matrix Equations
Xiaomin Duan,Huafei Sun,Xinyu Zhao
Journal of Applied Mathematics , 2014, DOI: 10.1155/2014/507175
Abstract: A Riemannian gradient algorithm based on geometric structures of a manifold consisting of all positive definite matrices is proposed to calculate the numerical solution of the linear matrix equation . In this algorithm, the geodesic distance on the curved Riemannian manifold is taken as an objective function and the geodesic curve is treated as the convergence path. Also the optimal variable step sizes corresponding to the minimum value of the objective function are provided in order to improve the convergence speed. Furthermore, the convergence speed of the Riemannian gradient algorithm is compared with that of the traditional conjugate gradient method in two simulation examples. It is found that the convergence speed of the provided algorithm is faster than that of the conjugate gradient method. 1. Introduction The linear matrix equation where are arbitrary real matrices, is a nonnegative integer, and denotes the transpose of the matrix , arises from many fields, such as the control theory, the dynamic programming, and the stochastic filtering [1–4]. In the past decades, there has been increasing interest in the solution problems of this equation. In the case of , some numerical methods, such as Bartels-Stewart method, Hessenberg-Schur method, and Schur and QR decompositions method, were proposed in [5, 6]. Based on the Kronecker product and the fixed point theorem in partially ordered sets, some sufficient conditions for the existence of a unique symmetric positive definite solution are given in [7, 8]. Ran and Reurings ([7, Theorem 3.3] and [9, Theorem 3.1]) pointed out that if is a positive definite matrix, then there exists a unique solution and it is symmetric positive definite. Recently, under the condition that (1) is consistent, Su and Chen presented an efficient numerical iterative method based on the conjugate gradient method (CGM) [10]. In addition, based on geometric structures on a Riemannian manifold, Duan et al. proposed a natural gradient descent algorithm to solve algebraic Lyapunov equations [11, 12]. Following them, we investigate the solution problem of (1) in the view of Riemannian manifolds. Note that this solution of (1) is a symmetric positive definite matrix and the set of all the symmetric positive definite matrices can be considered as a manifold. Thus, it is more convenient to investigate the solution problem with the help of these geometric structures on this manifold. To address such a need, a new framework is presented in this paper to calculate the numerical solution, which is based on the geometric structures on the
Statistical Analysis and Comparative Study of Energy Balance Components Estimated Using Micrometeorological Techniques during HUBEX/IOP 1998/99
用微气象方法估算淮河流域能量平衡(HUBEX/IOP 1998/99)的统计分析和比较研究

ZHU Zhilin,SUN Xiaomin,ZHANG Renhua,
ZHU Zhilin
,SUN Xiaomin,ZHANG Renhua

大气科学进展 , 2003,
Abstract: In order to study energy and water cycles in the Huaihe River Basin, micrometeorological measurements were carried out in Shouxian County, Anhui Province, during HUBEX/IOP (May to August 1998 and June to July 1999). The employed techniques included Bowen Ratio-Energy Balance (BREB) and Eddy Covariance (EC) methods. In this paper, the basic characteristics of the energy balance components in the district are analyzed. Furthermore, the results are compared with those from other regions of China. The main results are as follows: (1) There was a consistency between the available energy (R n G) and the sum of sensible (H) and latent (E) heat fluxes measured by the EC method (H+E)ec, but E br was slightly larger (about 10%) than E ec; (2) Most of the net radiation (R n) was used to evaporate water from the surface. During HUBEX/IOP in 1998 and 1999, the mean daily amounts of R n were 13.89 MJ m 2d 1 and 11.83 MJ m 2d 1, and the mean Bowen Ratios (β) were 0.14 (over ruderal) and 0.06 (over paddy) respectively; (3) The diurnal variation characteristic of β was larger and unsteady at sunrise and sunset, and smaller and steady during the rest of the daytime. Local advection appeared in the afternoon over paddy areas in 1999; (4) In comparison with the results from other regions of China, the mean β was the lowest (0.06) over paddy areas in the Huaihe River Basin and the highest (0.57) during June–August 1998 in Inner Mongolia grassland. The Bowen Ratio β is mainly related to the soil humidity.
Application Study on Multi-Vary Analysis  [PDF]
Xiaomin Xu
Modern Mechanical Engineering (MME) , 2013, DOI: 10.4236/mme.2013.31005
Abstract:

In this article, we studied the bearings made by one company in Shanghai. Through statistical process controlling the quality characteristic of bearings’ diameters and multi-vary analysis is applied to find the key variation factors which have an influence on the quality characteristic of the bearings, the quality level of the bearings of this company is improved.

Novel Understanding of Electron States Architecture and Its Dimensionality in Semiconductors  [PDF]
Xiaomin Ren
Optics and Photonics Journal (OPJ) , 2013, DOI: 10.4236/opj.2013.32B075
Abstract:

Some important insights into the electron-states-architecture (ESA) and its dimensionality (from 3 to 0) in a semiconductor (or generally crystalline) material are obtained. The self-consistency of the set of density of states (DOS) expressions with different dimensionalities is remediated through the clarification and rearrangement of the wave-function boundary conditions for working out the eigenvalues in the wave vector space. The actually too roughly observed and theoretically unpredicted critical points for the dimensionality transitions referring to the integer ones are revealed upon an unusual assumption of the intrinsic energy-level dispersion (ELD). The ELD based quantitative physical model had been established on an immediate instinct at the very beginning and has been properly modified afterwards. The uncertainty regarding the relationship between the de Broglie wavelength of electrons and the dimensionality transitions, seeming somewhat mysterious before, is consequentially eliminated. The effect of the material dimensions on the ELD width is also predicted and has been included in the model. The continuous evolution of the ESA dimensionality is convincingly and comprehensively interpreted and thus the area of the fractional ESA dimensionalities is opened. Another new assumption of the spatial extension shrinkage (SES) closely related to the ELD has also been made and thus the understanding of the behavior of an electron or, in a general sense, a particle has become more comprehensive. This work would manifest itself a new basis for further development of nanoheterostructures (or low dimensional heterostructures including the quantum wells, quantum wires, quantum dots and especially the hetero-dimensional structures). Expected

When “Parents Privilege Competition” Will Not Be an Exclusive Resource?  [PDF]
Xiaomin Guo
Open Journal of Social Sciences (JSS) , 2018, DOI: 10.4236/jss.2018.64004
Abstract:
We describe a common social phenomenon in this article. It is that when children grow up, in addition to their talents and efforts in comparison with their peers, the parental background between children is also an important stake in their competition. Parents’ social status and superior power will result in more social resources and opportunities for children. We call this phenomenon “parents privilege competition”. The root cause of this phenomenon is the serious hardening of the stratum and the poor social mobility in vertical society, which makes it difficult for children to have an equal competitive environment. After analyzing the phenomenon, this article discusses the causes of this phenomenon and the solutions.
An Automatic Instrument to Study the Spatial Scaling Behavior of Emissivity
Jing Tian,Renhua Zhang,Hongbo Su,Xiaomin Sun
Sensors , 2008,
Abstract: In this paper, the design of an automatic instrument for measuring the spatialdistribution of land surface emissivity is presented, which makes the direct in situmeasurement of the spatial distribution of emissivity possible. The significance of this newinstrument lies in two aspects. One is that it helps to investigate the spatial scalingbehavior of emissivity and temperature; the other is that, the design of the instrumentprovides theoretical and practical foundations for the implement of measuring distributionof surface emissivity on airborne or spaceborne. To improve the accuracy of themeasurements, the emissivity measurement and its uncertainty are examined in a series ofcarefully designed experiments. The impact of the variation of target temperature and theenvironmental irradiance on the measurement of emissivity is analyzed as well. Inaddition, the ideal temperature difference between hot environment and cool environmentis obtained based on numerical simulations. Finally, the scaling behavior of surfaceemissivity caused by the heterogeneity of target is discussed.
Interannual Variation of the Bowen Ratio in a Subtropical Coniferous Plantation in Southeast China, 2003-2012
Yakun Tang, Xuefa Wen, Xiaomin Sun, Huimin Wang
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0088267
Abstract: The interannual variation of the Bowen ratio, through its effect on the warming extent of available energy to the ecosystem land surface air, heavily influences the ecosystem microclimate and affects the hydrological cycle at both regional and global scales. Although the precipitation amount in southeast China is not expected to change greatly as a result of climate change, the precipitation frequency may be altered in the future. We explored the interannual variation of the Bowen ratio and its affecting mechanisms based on eddy covariance measurements in a subtropical plantation in southeast China during 2003–2012. The results indicated that the annual mean Bowen ratio was 0.35±0.06, with a range of 0.29–0.45. The Bowen ratio during the dry season (July-October) positively correlated with the annual Bowen ratio (R2 = 0.85, p<0.001). The effective precipitation frequency during the dry season, through its positive effect on shallow soil water content, indirectly and negatively affected the annual Bowen ratio. Between 2003 and 2012, the annual Bowen ratio exhibited a marginally significant decreasing trend (p = 0.061), meanwhile the effective precipitation frequency and shallow soil water content during the dry season increased significantly (p<0.001). The annual Bowen ratio may decrease further if the effective precipitation frequency and shallow soil water content during the dry season follow similar trends in the future. The warming effect of available energy to the surface air of our studied plantation may decline with the decreasing annual Bowen ratio.
An Evapotranspiration Assimilation Method Based on Ensemble Kalman Filter and à Trous Wavelet
Shaohui Chen,Jianwei Qi,Xiaomin Sun,Xiangzheng Deng,Jing Tian
Advances in Meteorology , 2013, DOI: 10.1155/2013/531810
Abstract: It is challenging to assimilate the evapotranspiration product (EP) retrieved from satellite data into land surface models (LSMs). In this paper, a perturbed ensemble Kalman filter (PEKF) and à trous wavelet transform (AWT) integrated method are proposed to implement the evapotranspiration assimilation. In this method, the AWT is used to decompose the EPs into multiple channels since it is very powerful in fusing high frequency spatial information of multisource data, and then the Kalman filter is performed in the AWT domain. The proposed method combines the advantages of the PEKF that is capable of accommodating model error and observation error, and the AWT can effectively perform multiresolution fusion. Assimilation experiment conducted with the Noah model and the EP retrieved from the MODIS data shows that the proposed method performs better than the traditional ensemble Kalman filter (EnKF) and PEKF methods. The analysis results fit well with the evapotranspiration observation at two field sites with different land surface conditions. These indicate that the proposed method is promising for assimilating regional scale satellite retrieved EP into LSMs. 1. Introduction Evapotranspiration (ET) is an important component of the water and energy exchanges between the atmosphere and land surface. It is crucial to accurately estimate ET for studying global or regional water and energy balances. Hence, good quality of spatial and temporal ET production (EP) can help to improve comprehension of water and energy cycle. However, this kind of EP is generally difficult to obtain in both dimensions of space and time because ET is influenced by many factors, such as air and skin temperatures, soil moisture, vegetation fraction, and horizontal advection. Up to now, there are two approaches to estimate the ET. One is site observations or remote sensing retrievals. Site observations have high spatial resolutions, but can only provide the EP for limited spatial locations [1]. Remote sensing retrievals have high spatial resolutions and can cover large range, but can only retrieve the instantaneous EP. The other is land surface models (LSMs). LSMs are probably the most efficient approach for continuously estimating ET on a large range [1]. Because of the imperfection of the physics of LSMs and the uncertainties of input and driving data, the EP of the LSMs may contain significant errors. Hence, data assimilation (DA) has been applied to integrate observational ET into LSMs [2]. DA provides a framework for improving the LSMs by updating the state variables of the LSMs
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