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251.
核心能力论在中国的应用 总被引:44,自引:1,他引:43
本文主要论述企业核心能力理论的特点,分析中国企业的适应性,即该理论的本土化问题。首先,对美欧国家90 年代兴起的企业战略理论———核心能力———进行剖析,指出它的背景、特点及局限性;接着,结合中国企业的现状,对该理论在中国的适用性进行分析,提出若干修正意见;最后,作者提出一种包含核心能力的、适用性广泛的企业战略能力模型 相似文献
252.
学位政策是教育政策的一个重要组成部分。从学位自身的运行逻辑来看,一个国家的学位政策体系一般包括四个方面的内容,即学位授予权的审定政策、学位中请者的培养政策、学位的授予政策、学位质量的评价政策。其中,学位授予权的审定政策是学位申请者的培养和学位的授予的政策性前提。学位申请者的培养政策是学位质量得以提高的基本途径和重要环节,学位的授予政策是学位授予权的审定和学位申请者的培养的最终体现和实现结果,而学位质量的评价政策是以上三个方面政策实施的重要保证。 相似文献
253.
254.
The distribution of the magnetic flux density in the magnetic field generator which provided travelling magnetic field was determined. The experiments using liquid gallium and aluminum - silicon alloy to observe the turbulent flow or remove inclusions were performed to obtain the basic principles how the distribution of the magnetic flux density took effect on removing inclusions from molten metal by electromagnetic field. The suitable area in the field for purifying metal was suggested. 相似文献
255.
氧化数概念在有机氧化还原反应中的应用 总被引:1,自引:0,他引:1
在有机化学中,引入了氧化数的概念,并用此概念对有机氧化还原反应的判断和有机氧化还原反应方程式的配平进行了探讨。 相似文献
256.
Chang Liu Linying Ji Sy-Miin Chow Boyoung Kang Leslie D. Leve Daniel S. Shaw Jody M. Ganiban Misaki N. Natsuaki David Reiss Jenae M. Neiderhiser 《Child development》2020,91(5):e1064-e1081
This study examined two possible mechanisms, evocative gene–environment correlation and prenatal factors, in accounting for child effects on parental negativity. Participants included 561 children adopted at birth, and their adoptive parents and birth parents within a prospective longitudinal adoption study. Findings indicated child effects on parental negativity, such that toddlers’ negative reactivity at 18 months was positively associated with adoptive parents’ over-reactive and hostile parenting at 27 months. Furthermore, we found that child effects on parental negativity were partially due to heritable (e.g., birth mother [BM] internalizing problems and substance use) and prenatal factors (e.g., BM illicit drug use during pregnancy) that influence children’s negative reactivity at 18 months. This study provides critical evidence for “child on parent” effects. 相似文献
257.
Kaila C. Bruer Sarah Zanette Xiao Pan Ding Thomas D. Lyon Kang Lee 《Child development》2020,91(4):e995-e1011
This study explored whether children's (N = 158; 4- to 9 years old) nonverbal facial expressions can be used to identify when children are being deceptive. Using a computer vision program to automatically decode children's facial expressions according to the Facial Action Coding System, this study employed machine learning to determine whether facial expressions can be used to discriminate between children who concealed breaking a toy(liars) and those who did not break a toy(nonliars). Results found that, regardless of age or history of maltreatment, children's facial expressions could accurately (73%) be distinguished between liars and nonliars. Two emotions, surprise and fear, were more strongly expressed by liars than nonliars. These findings provide evidence to support the use of automatically coded facial expressions to detect children's deception. 相似文献
258.
This work proposes the use of charged droplets driven by the Coulombic force as solution-phase reaction chambers for biological microreactions. A droplet can be charged near an electrode under dc voltage by direct contact to the electrode. This process is called electrical charging of droplet (ECOD). This charged droplet can then be transported rapidly between electrodes following the arc of an electric field line by exploiting electrostatic force. As on-demand electrocoalescence, both alkalization of phenolphthalein and bioluminescence reaction of luciferase in the presence of adenosine triphosphate are studied to test the feasibility of the biochemical microreactors using ECOD. Two oppositely charged droplets are merged to have a color change immediately after microchemical reaction. The applicability of an ECOD-driven droplet to measurement of glucose concentration is also tested. The glucose concentration is measured using a colorimetric enzyme-kinetic method based on Trinder’s reaction [J. Clin. Pathol. 22, 158 (1969)]. The color change in the merged droplet is detected with an absorbance measurement system consisting of a photodiode and a light emitting diode. 相似文献
259.
Optoelectrofluidic field separation (OEFS) of particles under light -intensity gradient (LIG) is reported, where the LIG illumination on the photoconductive layer converts the short-ranged dielectrophoresis (DEP) force to the long-ranged one. The long-ranged DEP force can compete with the hydrodynamic force by alternating current electro-osmosis (ACEO) over the entire illumination area for realizing effective field separation of particles. In the OEFS system, the codirectional illumination and observation induce the levitation effect, compensating the attenuation of the DEP force under LIG illumination by slightly floating particles from the surface. Results of the field separation and concentration of diverse particle pairs (0.82–16 μm) are well demonstrated, and conditions determining the critical radius and effective particle manipulation are discussed. The OEFS with codirectional LIG strategy could be a promising particle manipulation method in many applications where a rapid manipulation of biological cells and particles over the entire working area are of interest. 相似文献
260.
A simple method of fabricating mask-free microfluidic devices for biological analysis 总被引:1,自引:0,他引:1
We report a simple, low-cost, rapid, and mask-free method to fabricate two-dimensional (2D) and three-dimensional (3D) microfluidic chip for biological analysis researches. In this fabrication process, a laser system is used to cut through paper to form intricate patterns and differently configured channels for specific purposes. Bonded with cyanoacrylate-based resin, the prepared paper sheet is sandwiched between glass slides (hydrophilic) or polymer-based plates (hydrophobic) to obtain a multilayer structure. In order to examine the chip’s biocompatibility and applicability, protein concentration was measured while DNA capillary electrophoresis was carried out, and both of them show positive results. With the utilization of direct laser cutting and one-step gas-sacrificing techniques, the whole fabrication processes for complicated 2D and 3D microfluidic devices are shorten into several minutes which make it a good alternative of poly(dimethylsiloxane) microfluidic chips used in biological analysis researches. 相似文献