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71.
在高山峡谷河流上修建土石坝,若溢洪道布置在岸坡上,开挖工程量会很大。为节约工程造价可将溢洪道直接布置在坝体上。坝体溢洪道的泄槽一般都比较陡,为确保其稳定性现对泄槽底板进行多层水平锚筋加固。通过对泄槽底板的稳定分析得出锚筋的数量和长度与其受力的关系式,为今后工程设计提供理论依据。 相似文献
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Tissue Engineering: Effective Light Directed Assembly of Building Blocks with Microscale Control (Small 24/2017)
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74.
袁培生 《重庆理工大学学报(自然科学版)》1998,(4)
近年来,国外产品对我肆无忌惮地低价倾销,给我国经济发展带来极为不利的影响,怎样在加强对外开放、加速国际经济贸易自由化的同时,对国内产业给予切实有效的保护,这是我们当前急待解决的问题。国内企业面对洋货倾销的巨大冲击,应该有一个正确、全面的分析和认识,在激烈的市场竞争中彻底转变观念,学会应用反倾销这一国际通行而有效的合法手段来防止和制裁外国公司的不正当竞争行为,以保护自身利益。 相似文献
75.
本文在全面总结现有的国内外前方行驶车辆的视觉检测算法的基础上,利用由于光照因素使得前方车辆在图像内形成的底部阴影这一先验知识,建立了基于车辆阴影区域检测的前方障碍物视觉检测算法。 相似文献
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Bahman Hekmatshoar Alex Z. Kattamis Kunigunde Cherenack Sigurd Wagner James C. Sturm 《Journal of the Society for Information Display》2008,16(1):183-188
Abstract— The direct voltage programming of active‐matrix organic light‐emitting‐diode (AMOLED) pixels with n‐channel amorphous‐Si (a‐Si) TFTs requires a contact between the driving TFT and the OLED cathode. Current processing constraints only permit connecting the driving TFT to the OLED anode. Here, a new “inverted” integration technique which makes the direct programming possible by connecting the driver n‐channel a‐Si TFT to the OLED cathode is demonstrated. As a result, the pixel drive current increases by an order of magnitude for the same data voltages and the pixel data voltage for turn‐on drops by several volts. In addition, the pixel drive current becomes independent of the OLED characteristics so that OLED aging does not affect the pixel current. Furthermore, the new integration technique is modified to allow substrate rotation during OLED evaporation to improve the pixel yield and uniformity. The new integration technique is important for realizing active‐matrix OLED displays with a‐Si technology and conventional bottom‐anode OLEDs. 相似文献
79.
Jan Birnstock Tobias Canzler Michael Hofmann Andrea Lux Sven Murano Philipp Wellmann Ansgar Werner 《Journal of the Society for Information Display》2008,16(2):221-229
Abstract— Currently, three issues are identified that decide upon the commercial success of organic light‐emitting diodes (OLEDs), both in display and lighting applications: power efficiency, lifetime, and price competitiveness. PIN OLEDs are widely seen as the preferred way to maximize power efficiency. Here, it is reported that this concept also delivers the world longest lifetimes. For a highly efficient deep‐red PIN OLED, a half‐lifetime of 25,000 hours for a starting brightness of 10,000 cd/m2 and a minimal voltage increase over lifetime is reported. This value corresponds to more than 1 × 106 hours at 1000 cd/m2 using an exponent of n = 1.7, which was measured by driving the OLEDs at different starting luminances. Because there is no initial luminance drop, these PIN OLEDs also exhibit a very high 80% lifetime (>300,000 hours at 1000 cd/m2). New record lifetime values for blue and green will be reported as well. Additionally, further topics that have impact on the production yield and cost such as the newly developed air‐stable organic n‐doping material NDN‐26 and top‐emitting structures will be discussed. 相似文献
80.
An NP-hard production–distribution problem for one product over a multi-period horizon is investigated. The aim is to minimize total cost taking production setups, inventory levels and distribution into account. An integer linear model is proposed as a compact problem specification but it cannot be solved to optimality for large instances. Instead of using a classical two-phase approach (production planning and then route construction for each day), metaheuristics that simultaneously tackle production and routing decisions are developed: a GRASP (greedy randomized adaptive search procedure) and two improved versions using either a reactive mechanism or a path-relinking process. These algorithms are evaluated on 90 randomly generated instances with 50, 100 and 200 customers and 20 periods. The results confirm the interest of integrating production and distribution decisions, compared to classical two-phase methods. Moreover, reaction and path-relinking give better results than the GRASP alone. 相似文献