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排序方式: 共有2038条查询结果,搜索用时 250 毫秒
91.
This study explores the impact of governmental support policies on the innovation of SMEs in the regional strategic industries in South Korea. We use the technological development assistance funds as a proxy for governmental support policies for SMEs in the regional industries in Korea. The innovation of SMEs is measured by technological innovation: patent, utility model, trademark, and new design registrations. Before empirically testing the impact of governmental support policies on the innovation of SMEs, this study reviews the literature concerning the innovation and the governmental support policies of SMEs in regional industries. Results from empirical models, which simultaneously control for factors which were thought to affect the innovation of regional SMEs, indicate that a positive relationship exists among the technological development assistance by the Korean government and patent acquisitions and new design registrations of regional SMEs. Networks with universities also have a positive relationship with patent acquisitions and new design registrations of regional SMEs. This study suggests there is an importance to governmental financial aids for regional SME innovations, and there is an importance to the need to build a strong social relationship in today's networked economy.  相似文献   
92.
We present dual-mode, on-demand droplet routing in a multiple-outlet microfluidic device using an oil-based magnetic fluid. Magnetite (Fe3O4) nanoparticle-contained oleic acid (MNOA) was used as a carrier phase for droplet generation and manipulation. The water-in-MNOA droplets were selectively distributed in a curved microchannel with three branches by utilizing both a hydrodynamic laminar flow pattern and an external magnetic field. Without the applied magnetic field, the droplets travelled along a hydrodynamic centerline that was displaced at each bifurcating junction. However, in the presence of a permanent magnet, they were repelled from the centerline and diverted into the desired channel when the repelled distance exceeded the minimum offset allocated to the channel. The repelled distance, which is proportional to the magnetic field gradient, was manipulated by controlling the magnet''s distance from the device. To evaluate routing performance, three different sizes of droplets with diameters of 63, 88, and 102 μm were directed into designated outlets with the magnet positioned at varying distances. The result demonstrated that the 102-μm droplets were sorted with an accuracy of ∼93%. Our technique enables on-demand droplet routing in multiple outlet channels by simply manipulating magnet positions (active mode) as well as size-based droplet separation with a fixed magnet position (passive mode).  相似文献   
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This paper reports a method to control the fluid flow in paper-based microfluidic devices simply by pressing over the channel surface of paper, thereby decreasing the pore size and permeability of a non-woven polypropylene sheet. As a result, fluid resistance is increased in the pressed region and causes flow rate to decrease. We characterize the decrease of flow rate with respect to different amounts of pressure applied, and up to 740% decrease in flow velocity was achieved. In addition, we demonstrate flow rate control in a Y-shaped merging paper and sequential delivery of multiple color dyes in a three-branched paper. Furthermore, sequential delivery of multiple fluid samples is performed to demonstrate its application in multi-step colorimetric immunoassay, which shows a 4.3-fold signal increase via enhancement step.  相似文献   
94.
We present an optofluidic microvalve utilizing an embedded, surface plasmon-enhanced fiber optic microheater. The fiber optic microheater is formed by depositing a titanium thin film on the roughened end-face of a silica optical fiber that serves as a waveguide to deliver laser light to the titanium film. The nanoscale roughness at the titanium-silica interface enables strong light absorption enhancement in the titanium film through excitation of localized surface plasmons as well as facilitates bubble nucleation. Our experimental results show that due to the unique design of the fiber optic heater, the threshold laser power required to generate a bubble is greatly reduced and the bubble growth rate is significantly increased. By using the microvalve, stable vapor bubble generation in the microchannel is demonstrated, which does not require complex optical focusing and alignment. The generated vapor bubble is shown to successfully block a liquid flow channel with a size of 125 μm × 125 μm and a flow rate of ∼10 μl/min at ∼120 mW laser power.  相似文献   
95.
The "feel better" effect of exercise has been well established, but the optimal intensity needed to elicit a positive affective response is controversial. In addition, the mechanisms underlying such a response are unclear To clarify these issues, female undergraduate students were monitored for electroencephalographic (EEG) and self-reported affective responses during the recovery period following rest, low, moderate, and high intensities of treadmill running, each lasting 30 min. Frontal EEG asymmetry and self-reported vigor scores following exercise at all three intensities were significantly elevated compared to those observed following rest. The results suggest that steady-state aerobic exercise bouts executed at varying intensities induce a similar affective response during the recovery period when assessed at both the behavioral and psychophysiological levels.  相似文献   
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Over the centuries, universities have functioned as gatekeepers and treasurers of received knowledge, while concomitantly furthering innovative contributions to society. Yet, when cultivating research ‘silos’, universities encourage scholars to explore in seeming isolation. Out of such tensions, universities have supported, and will continue to pursue, different kinds of, and approaches to, furthering knowledge and creativity. In the past, the humanities had been central to this mission. More recently, however, the efficient and global acceleration of consumer-oriented ‘knowledge production and consumption’ seems to form a critical factor upsetting the centrality of the humanities in university cultures. In this context, exploring the academic communities of the late middle ages proves to be a useful exercise. Forged in strong relationships with ecclesiastical and secular powers, mediaeval universities nonetheless share critical concerns with today’s academic institutions; thus, they too were constrained by the need to attract and exact excellence, to navigate relationships with their immediate environs, and to train professionals, who could ensure continuity in academic communities, the church, and the imperial courts. In other words, mediaeval universities also experienced polarising tensions that reveal consonances between then and now and that can gloss today’s acceleration driving the consumer model of knowledge production and consumption, while also encouraging scholars to form more explicit links to external constituencies.  相似文献   
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