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101.
Akihiro Yamada Kuniko Kojima Koji Minami Hiroaki Sugiura Hiroshi Kida Kenji Samejima 《Journal of the Society for Information Display》2012,20(7):390-396
Stationary projectors mainly used in system applications have recently gained a wider application range, including general presentations in halls and large conference rooms and being used, for example, in digital signage and for monitoring purposes. Consequently, they are required to meet new market demands for durability, reliability, and flexibility in installation in addition to their conventional basic performance such as especially high brightness. To achieve especially high brightness, a new optical system with two lamps is proposed; the profile of the cover glass that prevents the glass from scattering is made aspherical, the profile of the beam‐combining mirror is improved with its position optimized, and the size of the incident plane of the integrator rod is made larger (1.1 times). These measures resulted in an optical system of an even higher efficiency with 7000 lm, which is the highest in its class (according to a June 2010 investigation). Also, the arrangement of two parallel lamps completely eliminated the effect of heat passing from one lamp to the other, which helped secure durability, reliability, and flexibility in installation. Furthermore, the combined use of the unique non‐telecentric optical system, adopted from the conventional single‐lamp model, helps maintain the class‐highest contrast ratio.1,2 相似文献
102.
Shintaro Nakano Nobuyoshi Saito Kentaro Miura Tatsunori Sakano Tomomasa Ueda Keiji Sugi Hajime Yamaguchi Isao Amemiya Masato Hiramatsu Arichika Ishida 《Journal of the Society for Information Display》2012,20(9):493-498
We have successfully reduced threshold voltage shifts of amorphous In–Ga–Zn–O thin‐film transistors (a‐IGZO TFTs) on transparent polyimide films against bias‐temperature stress below 100 mV, which is equivalent to those on glass substrates. This high reliability was achieved by dense IGZO thin films and annealing temperature below 300 °C. We have reduced bulk defects of IGZO thin films and interface defects between gate insulator and IGZO thin film by optimizing deposition conditions of IGZO thin films and annealing conditions. Furthermore, a 3.0‐in. flexible active‐matrix organic light‐emitting diode was demonstrated with the highly reliable a‐IGZO TFT backplane on polyimide film. The polyimide film coating process is compatible with mass‐production lines. We believe that flexible organic light‐emitting diode displays can be mass produced using a‐IGZO TFT backplane on polyimide films. 相似文献
103.
Kirwan B 《Applied ergonomics》1992,23(6):371-381
This is the second part of a two-part review of human error identification (HEI) approaches in human reliability assessment (HRA). Part 1 reviewed the probabilistic risk assessment (PRA) context in which HRA occurs, and then detailed 12 HEI techniques which have evolved in the field of HRA. Part 2 attempts to compare the way these techniques perform against a range of criteria relevant to HEI theoretical and empirical validity, and practical usefulness in applied HRA. It is hoped that these comparisons will help assessors in the selection of techniques for practical applications. The comparisons also point to research and development needs in the area of applied HEI. 相似文献
104.
研究提高软件可靠性预测精度问题,对软件可靠性研究已成为当前软件工程的一个研究热点,传统的单一软件可靠性模型由于使用的技术及提取的信息有限,软件可靠性预测精度不高。为提高软件可靠性预测精度,在建立多种单一软件可靠性预测模型的基础上,提出一种样本点的多模型变权重组合模型。将多种预测技术有效地聚合在一起,取长补短,在样本数据有限的情况下,不仅改善了样本内学习能力也增强了样本外的泛化能力,提高了综合预测精度。仿真验证模型无论在样本内还是样本外都较优于经过模拟退火算法优化的BP神经网络(SA-BP)及经过遗传算法优化的最小二乘支持向量机(GA-LSVM),说明变权重组合模型是一种精度更高的软件可靠性失效数据预测模型,具有较好的应用推广价值。 相似文献
105.
卢宇彤 《计算机工程与科学》2012,34(8):17-23
高性能计算技术以加速度迅猛发展,继千万亿次系统研制成功以后,超级计算机的性能又快速提升至数万万亿次,国际学术界与工业界普遍预期在2018年左右将出现极大规模并行的百万万亿次系统(Exascale Computing,简称E级系统)。本文从最新一届TOP500榜单入手分析了超级计算领域的技术动态,在此基础上,探讨了未来E级系统的发展趋势及其所面临的能耗、可扩展、可靠性和可编程性等关键技术问题。 相似文献
106.
本文简要介绍了人工神经网络,BP神经网络的结构、训练和学习规则以及人工神经网络非线性时间序列预测的应用概况。 相似文献
107.
本文以可靠性技术,针对继电器在使用时主要失效模式触点失效故障进行分析,从触点材料、控制负载、抑制触点电弧,并对触点在常用环境下不合理使用等问题一并进行了较详细的阐述。 相似文献
108.
109.
110.
Hong Mei Gang Huang Tiancheng Liu Junguo Li 《International Journal of Software and Informatics》2007,1(1):101-128
Being the most popular runtime infrastructure for distributed systems, middleware can be viewed as a collection of common services. Since the development, deployment and maintenance of distributed systems rely largely on middleware services, the failure of middleware services puts a significant impact on the reliability and availability of the whole system. Though recovery-based fault tolerance is an effective way to improve the reliability of middleware services, it is far away from practice mainly because of the high complexity and cost of the recovery of correlated failures between interdependent services. In this paper,a framework for detecting and recovering the correlated failures of middleware services in an automated way is presented. First, the problem is investigated from two perspectives, i.e.,analyzing the role and impact of middleware services and illustrating a set of correlated failures in J2EE standard services as motivating examples. Then, a general coordinated recovery model is constructed with the elements necessary and su±cient for detecting and recovering correlated failures in middleware services. The supporting framework is demonstrated on three J2EE application servers, i.e., PKUAS, JBoss and JOnAS, one by one without fundamental modifications. Finally, based on the three enhanced application servers, many cases on J2EE common services, including the transaction service, database service, naming and directory service, security service and messaging service, are studied. The experiment results show the effectiveness and applicability of the framework presented in this paper. 相似文献