How Chinese State-Owned Enterprises Change Their Dynamics in New Product Innovation?

The innovation of state-owned enterprises and its adaptation to the market competition have been in the spotlight of studies. According to the panel data form Statistics on Science and Technology-Oriented Activities of Industry Enterprises, this research measures and contrasts the new product innovation investment and performance of Chinese State-Owned Enterprises (SOEs) and non-SOEs. It reveals that market competition is a positive effect on new product innovation input and output of state-owned enterprises, as non-SOE, the relationship between competition intensity and new product innovation output of state-owned enterprises appears exponential relationship. Furthermore, it discovers that non-SOE is more sensitive to competition intensity than SOE. Under the different competitive environment, both of them play differents role on promoting development of innovation and stabilising the market

Characterizing Surface Roughness From Pressure-Joint Closure Measurements Using Inversion Procedure

An inversion procedure has been formulated to estimate the surface roughness of a joint (fracture) from the measured pressure-closure data. A gamma distribution for the local minima (or maxima) on a topography profile was used to account for the skewness in the measured distribution of the asperities. By using the distribution, the average height [bar over z] and the standard deviation a of the profile can also be characterized. An inversion procedure was formulated based on the modification of the theory proposed by Brown and Scholz (1985) and has been successfully tested with synthetic data. The inversion finds average height [bar over z][subscript 1], standard deviation σ, and average aperture. These three parameters characterize the surface roughness and aperture of a fracture and are the topography parameters governing permeability, electric conductivity and other transport properties of the fracture. Pressure-closure data from laboratory measurement of a rough and a smooth joint were also inverted to find the joint properties. The results agree with the profile measurement quite well. The variations of transport properties of a fracture with pressure are also studied.Massachusetts Institute of Technology. Full Waveform Acoustic Logging ConsortiumUnited States. Dept. of Energy (Grant DE-FG02-86ER13636

A Short Note On Permeability Anisotropy In Heterogeneous Porous Media

This paper presents some new results of theoretical modeling on permeability anisotropy in heterogeneous porous media. It is shown that the lineation of heterogeneities results ·in permeability anisotropy. However, to produce strong anisotropy, the permeability contrast between the lineated high permeability region and the background must be very high. We demonstrate this using two examples. The first is the fracture model in which the background has negligible permeability compared to the fractures. In the second example the fractures are replaced by impermeable stripes and the background has high permeability. In both cases permeability anisotropy with an order of magnitude difference is produced. These results compare well with the results of laboratory experiments performed to evaluate permeability anisotropy.Massachusetts Institute of Technology. Borehole Acoustics and Logging ConsortiumUnited States. Dept. of Energy (Grant DE-FG02-86ER13636

Modeling Fluid Flow In Heterogeneous And Anisotropic Porous Media

Permeability distribution in reservoirs is very important for the flow of water or oil and gas. In this study, the effects of various heterogeneous permeability distributions on the flow field are simulated using the finite difference technique. We have simulated the flow for two types of heterogeneous distributions, one is Gaussian and the other is self-similar or fractal, the latter being much rougher than the former. The results show that the flow is not sensitive to the roughness of the distribution. In the case of lineated heterogeneities, anisotropy in the flow properties occurs. The anisotropy is not very significant if the lineated highly permeable regions are surrounded by less permeable regions. However, in the case of lineated fractures, where the background permeability is small, the flow is very sensitive to the direction of the lineation, such anisotropy can produce orders of magnitude difference in permeability. Furthermore, it is shown that the degree of anisotropy depends on the connectivity of the fractures. The anisotropy decreases with decreasing connectivity.Massachusetts Institute of Technology. Full Waveform Acoustic Logging ConsortiumUnited States. Dept. of Energy (Grant DE-FG02-86ER13636

Transient Fluid Flow In Heterogeneous Porous Media

A stable Alternating Direction Implicit finite-difference algorithm is used to model transient fluid flow in heterogeneous porous media. In connection with the laboratory system for pressure transient testing of core permeability, the effects of permeability heterogeneities on the characteristics of the pressure transient were investigated. The results show that the early portion of the pressure transient is sensitive to the heterogeneity, while the late time portion is primarily controlled by the effective permeability of the sample. As in the steady flow case, lineation in permeability distribution produces anisotropy in measured permeability. Particularly, in the case of lineated fractures, where the background permeability is small, such anisotropy can produce an order of magnitude difference in permeability.Massachusetts Institute of Technology. Borehole Acoustics and Logging ConsortiumUnited States. Dept. of Energy (Grant DE-FG02-86ER13636

Solute Transport In Heterogeneous Porous Media

Solute mass transport in porous media is strongly correlated with pore fluid flow. The analysis of solute transport is an effective means for studying medium heterogeneities. In this study, we discuss the effects of heterogeneity on the tracer transport. Assuming steady fluid flow, we have simulated tracer transport in various permeability heterogeneities. The results show that the tracer distribution is very closely correlated with the medium heterogeneity, and anisotropy in tracer transport exists when there is permeability lineation and large permeability contrast between low- and high-permeability regions. An important feature by which the tracer transport differs from the fluid flow field is that the tracer transport tends to smear the effects of a thin non-permeable layer (or small permeability barriers) through diffusion into the low-permeability layer, while the fluid flow cannot penetrate the low-permeability layer. In addition, the modeling results also show that the tracer transport strongly depends on the tracer source dimension, as well as the flow source dimension.Massachusetts Institute of Technology. Borehole Acoustics and Logging ConsortiumUnited States. Dept. of Energy (Grant DE-FG02-86ER13636

Riemannian Gradient Algorithm for the Numerical Solution of Linear Matrix Equations

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 Q=X+∑i=1mAiTXAi. 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

Helping Students Learn through Students Feedback Literacy Method

Feedback is the critical element to improve students’ learning quality. During the ten years, many papers have focused on the students’ feedback literacy (SFL) and teachers’ feedback literacy (TFL). This article aims to systematize the core research concept of different teams and suggest strategies for training SFL. For the qualitative method, the researchers interviewed 26 teachers from two vocational colleges in China. For the quantitative method, the authors analyzed 523 students’ data and questionnaires to determine whether there is significant difference between them. Although there is no significant difference the two college between the south and north part of China, using feedback effectively is an important life skill required to function effectively in the workplace and relationships. We summarize crucial ideas about designing effective feedback strategies throughout the paper. With this in mind, we invite readers to consider what small changes you would make to your practice and how you would share your learning with your colleagues and students.