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991.
992.
针对空中移动目标识别问题,提出了一种基于动态行为学习的识别方法。首先,从数据源中提取目标要素,经过标注形成目标数据特征集;其次,基于应用场景进行特征组合,形成特征模型要素;然后,基于深度学习算法进行模型训练,得到评估最优的模型参数;最后,利用训练后的模型进行目标识别处理。通过数值仿真验证,该方法能够有效地识别无业务规则的目标身份。 相似文献
993.
Young Hoon Jung Seong Kwang Hong Hee Seung Wang Jae Hyun Han Trung Xuan Pham Hyunsin Park Junyeong Kim Sunghun Kang Chang D. Yoo Keon Jae Lee 《Advanced materials (Deerfield Beach, Fla.)》2020,32(35):1904020
Flexible piezoelectric acoustic sensors have been developed to generate multiple sound signals with high sensitivity, shifting the paradigm of future voice technologies. Speech recognition based on advanced acoustic sensors and optimized machine learning software will play an innovative interface for artificial intelligence (AI) services. Collaboration and novel approaches between both smart sensors and speech algorithms should be attempted to realize a hyperconnected society, which can offer personalized services such as biometric authentication, AI secretaries, and home appliances. Here, representative developments in speech recognition are reviewed in terms of flexible piezoelectric materials, self-powered sensors, machine learning algorithms, and speaker recognition. 相似文献
994.
We implemented pseudo-linear feedback shift-register-based physical unclonable functions (PL-PUFs) on silicon and analyzed their performances in terms of reproducibility, uniqueness, and resistance to machine-learning attacks. A PL-PUF is compact and high-throughput PUF, slightly oversensitive to voltage fluctuations. To overcome this drawback, we developed a capturing signal generation circuit that was tolerant to the reproducibility degradation caused by supply voltage changes. We also implemented a Built-In Self-Test (BIST) circuit with an irreversible destruction mechanism to enable exceedingly fast challenge–response pairs (CPRs) for the PUFs before shipping. After the CPRs were evaluated, the BIST circuit became invulnerable to exploitation by attackers. 相似文献
995.
996.
997.
Marely G. Figueroa-Pérez Iza F. Pérez-Ramírez Octavio Paredes-López Candelario Mondragón-Jacobo 《International Journal of Food Properties》2018,21(1):1728-1742
This study aimed to determine the phytochemical profile and nutraceutical properties of nopal cladodes (Opuntia ficus-indica) at different stages of maturity. Medium-age cladodes showed the highest total saponins, phytosterols, and indigestible fiber, as well as the highest in vitro antioxidant capacity and digestive enzymes inhibitory activity. Furthermore, these cladodes presented the highest content of p-hydroxybenzoic acid, p-coumaric acid, rutin, narcissin, nicotiflorin, β-sitosterol, and sitosteryl-3-β-glucopyranoside, as well as several amino acids, organic acids, and fatty acids. Whereas young cladodes contained the highest concentration of condensed and hydrolyzable tannins. These results demonstrated that maturity affects the nutritional and nutraceutical properties of nopal cladodes. 相似文献
998.
999.
In this paper, a low-pressure capacitively coupled plasma discharge sustained in an argonoxygen
mixture was studied in order to evaluate its properties in terms of inactivation of
Staphylococcus aureus. The plasma parameters as electron temperature and plasma density were
measured by the Langmuir probe (Ne ≈ 1015 m−3, Te ≈ 1.5 eV), while the neutral atom density
was in the range of 1021 m−3. In the plasma phase, oxygen radicals were taken as reference of the
reactive species with antimicrobial activity, and oxygen spectral lines, over a range of plasma
process parameters, were investigated by the optical emission spectroscopy. Optimal plasma
conditions were found, and a count reduction of 4 log in a few minutes of the bacterium proves
the potentiality of an industrial grade plasma reactor as a sterilization agent. 相似文献
1000.
Lu Zhang Junjie Shang Tim Pelton Leslee Francis Pelton 《Journal of Computer Assisted Learning》2020,36(4):540-548
With the advent of mobile technologies, well-designed fraction apps can be used to help children gain fraction knowledge, a challenging topic for both teachers and students. The present pilot study adopted a quasi-experimental design to investigate whether children can learn fraction concepts equally well if half of the lesson time (20 min) is replaced with game-based learning. Keeping the total lesson time (40 min) identical, the control group (N = 33) received traditional instruction, and the experimental group (N = 32) was presented with a blended learning approach spending half of the class time (20 min) playing tablet-based fraction games, where each of the learners had their own tablet. The results suggested that in the posttest, the experimental group achieved similar learning gains to the control group and appear to have achieved better performance in the transfer test than the control group. This paper also discusses the efficiency of game-based learning, the mechanism of how fraction games might enhance learning, and the potential of integrating game-based learning in educational settings. 相似文献