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This paper proposes an instance?learning?based intrusion?detection system (IL?IDS) for wireless sensor networks (WSNs). The goal of the proposed system is to detect routing attacks on a WSN. Taking an ... 相似文献
64.
Jatindra N Kalita Pradip Kr Mahanta 《Journal of the science of food and agriculture》1993,62(2):105-109
Black teas manufactured in Darjeeling and Assam were analysed for various macrominerals such as P, K, Ca, Mg and microminerals such as Mn, Fe and Cu. A considerable amount of minerals, eg K (40-46 mg), Mg (2.7-3.0 mg), Ca (0.48-0.66 mg) and traces of Mn (0.28-0.40 mg), Fe (0.16-0.20 mg), P (29-41 μg) and Cu (12-22 μg) were found in a cup of black tea brew. Black teas manufactured from the leaf coming from a pruned section and fine portion usually showed higher mineral content than tea manufactured from unpruned sections and coarse grade teas of Darjeeling. Assam CTC tea was found to be richer in mineral content compared to Darjeeling orthodox tea. 相似文献
65.
Stress-strain relationships were determined for heated egg white gels. Compressive strain at failure was independent of protein concentration, while stress at failure increased with protein concentration. Between the length ratios of 1.6 and 2.4 before and after compression, the heated egg white gels followed the Mooney Rivlin model. In stress relaxation, the asymptotic hypothetical equilibrium modulus increased with protein concentration. 相似文献
66.
通过对CS-444碳硫分析仪空白的来源、测量和计算广阔支及空白值与助熔剂、坩埚、助燃气体和分析气路等因素的的研讨,提出了降低和稳定空白值的一些具体方法。 相似文献
67.
Jorge Laine Joaquin Brito Francisco Severino Germán Castro Patricia Tacconi Simón Yunes José Cruz 《Catalysis Letters》1990,5(1):45-54
The effect of prereduction on CO oxidation activity of unsupported copper-chromite oxide catalysts was examined. Results were found to be in good agreement with two mechanisms for a surface copper enrichment due to CO prereduction which produced an activity increase in the copper-chromite catalyst. 相似文献
68.
C. Ciavatta M. Govi L. Vittori Antisari P. Sequi 《Nutrient Cycling in Agroecosystems》1990,25(3):167-174
An enzymatic approach to assess the stability of organic matter extracted from organic fertilizers and amendments is proposed. The use of 0.1M NaOH plus 0.1M Na4P2O7 previously suggested as a suitable extractant solution for soil organic matter was also found satisfactory for the extraction of organic matter from organic fertilizers and amendments, especially when the temperature was raised to 65°C. The presence of nonhumified compounds in the extracts from organic fertilizers may interfere considerably during fractionation of organic carbon. An enzymatic hydrolysis with lipase, lysozyme and pronase, added sequentially to the extracts, led to an appreciable reduction in the interference. The interference was further reduced by carrying out a successive acid hydrolysis with 3N H2SO4; in this case the DH values (percentage of humified fractions with respect to total extractable carbon) were reduced to less than 10% in all organic fertilizers, but remained higher than about 70% in organic amendments. 相似文献
69.
A semiconducting single-walled carbon nanotubes (s-SWCNTs) interlayer between poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) and n-Si was used for high performance organic-Si hybrid photovoltaic (PV) devices. The s-SWCNTs films with different thickness were utilized to investigate the PV effect on PEDOT:PSS/Si device performance. The surface potential of Si substrate with s-SWCNTs was dramatically reduced, which increased the compatibility between Si and PEDOT:PSS. In addition, s-SWCNTs with good semiconducting properties, guaranteed the charge transfer between Si and PEDOT:PSS. Therein, the electrical contact was dramatically improved with addition of s-SWCNTs interlayer, which led to increased fill factor. A power conversion efficiency (PCE) of 12.14% was achieved with an optimized thickness of s-SWCNTs layer. The s-SWCNTs interface layer was fabricated by a simple solution processed method, which was easily coupled with organic-Si solar cells to enhance the PCE. 相似文献
70.
本文根据线光源高压汞灯的特点设计了一个用于光动力疗法的光反应室 ,它输出的光功率连续可调 ,波段选择简单灵活 相似文献