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文章分析了网络安全等级保护2.0时期国家标准的新变化对等级测评结论可能产生的影响,并用实际案例和数据论述了以往描述的基于测评指标和基于测评对象的定量分析方法存在的局限性。根据网络安全等级保护国家标准结构和内容的新特点,结合新的等级测评结论表述方法,文章提出了调整和优化定量计算产生等级测评结论的思路,给出了缺陷扣分的原理和缺陷扣分的定量计算方法,并比较了各种定量计算方法在计算结果上的差异,提出了适合新标准的测评结论定量计算公式。 相似文献
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Lin-jiang CHAI Ke CHEN Shu-yan WANG Ji-ying XIA Ting-ting WANG Zhi-nan YANG 《中国有色金属学会会刊》2018,28(7):1321-1328
Multiple characterization and analysis techniques including electron backscatter diffraction (EBSD), electron channeling contrast (ECC) imaging, transmission electron microscopy (TEM) and microhardness test were jointly employed to investigate microstructural characteristics such as local composition, morphology, grain boundary characteristics and interphase orientation relationship of a forged Zr–2.5Nb alloy before and after β-air-cooling. Results show that the as-forged specimen is composed of equiaxed and lamellar α grains and continuous net-like β-Zr films. After the β-air-cooling, the microstructure of the specimen is featured by basket-weave Widmanstätten structure, in which the inter-α-plate second phases are nanoscale β-Zr. Analyses for crystallographic orientations reveal that the Burgers relationship has been strictly followed during the β→α cooling. Compared to the as-forged specimen, the hardness of the β-air-cooled specimen is higher, which could be attributed to the decreased structural sizes of both α and β phases, and the increased fraction of high angle boundaries as well. 相似文献
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交通信号灯识别包括检测和状态识别,在智能交通系统中发挥重要作用。基于YOLOv3算法提出了一种交通信号灯检测与状态识别模型。针对交通信号灯相较于交通场景中其他目标具有尺度小的特性进行了算法的设计:降低骨干网络的下采样倍率以增加小尺度目标的特征描述能力;通过增大特征图的尺度来改进多尺度特征融合;引入广义交并比作为检测任务的损失函数来改进目标边界框的回归效果。同时,根据交通信号灯本身的特性,使用颜色和形状约束的方法对信号灯进行状态识别和类别验证。最后在公开的Bosch交通信号灯数据集上和实际的城区道路进行了实验验证。实验结果表明,所提出的算法能够提升交通信号灯识别的精度和召回率,识别准确率可以达到90%左右。 相似文献
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Qi Li Xing Wang Fuan Wang Da Chen Xiaolei Xiao Helin Zou 《Ceramics International》2018,44(7):7709-7715
Pb(NdxZr0.52Ti0.48)O3 (PNZT) (x = 0%, 1%, 2%, 3%, 4%, 5%) thin films were prepared by sol-gel process to investigate the effects of neodymium substitution on crystalline orientation, microstructure and electric properties of lead zirconate titanate (PZT) films. X-ray diffraction (XRD) and scanning electron microscope (SEM) analysis showed that PNZT films with Nd doping concentration below 3% exhibited dense perovskite structure with (100) preferred orientation. The average grain size of PNZT films decreased as the Nd substitution increased. The maximum dielectric constant, remnant polarization and minimum coercive field were obtained in 2% Nd-doped PZT films. Fatigue resistance was also improved significantly with 2% Nd dopant. 相似文献
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Cristina Dai Prá Martens Franklin Jean Machado Mauro Luiz Martens Filipe Quevedo Pires de Oliveira e Silva Henrique Mello Rodrigues de Freitas 《International Journal of Project Management》2018,36(2):255-266
Entrepreneurial orientation (EO) is a strategic posture of an organization, and it is related to basic policies and practices for the development of entrepreneurial actions looking for creating competitive advantages. This study develops and tests a model of the relationship between entrepreneurial orientation and project success in Brazilian context. As quantitative research, a survey was used to collect data. A sample of 100 valid answers from project practitioners was treated through the structural equation modeling method. As research implications, the main result points out the positive correlation between the entrepreneurial orientation and the project success, contributing to the development of this research subject and helping to minimize the gap in the literature that addresses the relationship between project success and EO. In practical terms, understanding that innovativeness, risk taking, proactiveness, autonomy and competitive aggressiveness (the dimensions of the EO) can contribute to project success and can also indirectly impact on organizational performance, could help organizations get competitive advantage when developing correlate factors. Finally, the results suggest that practices of project management can be aligned to the firm's entrepreneurial orientation to enable firms to attain better results in their projects and generate a competitive advantage. On other hand, given the proportion of the impact of EO on project success (20.3%) identified in this study, it is critical that project management professionals expand their horizon to recognize other factors that affect project success. 相似文献
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ABSTRACTWith a greater number of B2B firms integrating customers into the new product development (NPD) process, how to utilize customer involvement in NPD is an important decision because it may be a double-edged sword carrying both bright and dark sides. Utilizing a sample of 193 B2B firms across various industries, we validate previous research that suggests market orientation positively influences NPD performance and subsequently examine how this relationship may either be enhanced or diminished contingent upon how customers are utilized in the NPD process. The results show that the market orientation–NPD performance relationship is enhanced by having customers participate in a greater number of activities throughout NPD (customer participation breadth) and diminished when customers are involved at deeper levels (customer participation depth). This research suggests that the exact involvement of customers is a critical decision and has clear implications for the dialogues about customer involvement and management of customer relationships. 相似文献
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针对采用相关滤波的判别式目标跟踪遇到的瓶颈问题:由于目标快速移动引起边界效应,使得相关滤波器在学习与更新过程中可能会引入错误,最终错误的累积将导致跟踪失败。在采集深度学习特征与样本相似性度量的基础上,提出一种引入交替方向乘子方法的改进相关滤波目标跟踪算法,选择DCNN深度特征有效地表征待跟踪目标的初始状态,通过在线分类过程中样本相似性比对与半监督学习,辅助解决相关滤波器在学习过程中存在的自学习问题。所提目标跟踪算法特别适合训练样本为持续获得的、同时存储空间较小的机器学习过程,提高目标在快速运动与部分遮挡等复杂情况下的跟踪成功率,针对VOT2016标准测试视频的实验表明:当目标面临快速运动时,对比CN、SAMF、STC算法,所提DA-CFT跟踪算法将跟踪成功率分别由60.4%~73.4%、67.2%~82.9%、80.9%~88.1%提升至85.6%~91.0%。 相似文献
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在空地协同背景下,地面目标的移动导致其在无人机视角下外观会发生较大变化,传统算法很难满足此类场景的应用要求。针对这一问题,提出基于并行跟踪和检测(PTAD)框架与深度学习的目标检测与跟踪算法。首先,将基于卷积神经网络(CNN)的目标检测算法SSD作为PTAD的检测子处理关键帧获取目标信息并提供给跟踪子;其次,检测子与跟踪子并行处理图像帧并计算检测与跟踪结果框的重叠度及跟踪结果的置信度;最后,根据跟踪子与检测子的跟踪或检测状态来判断是否对跟踪子或检测子进行更新,并对图像帧中的目标进行实时跟踪。在无人机视角下的视频序列上开展实验研究和对比分析,结果表明所提算法的性能高于PTAD框架下最优算法,而且实时性提高了13%,验证了此算法的有效性。 相似文献