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61.
Blind Source Separation of Instantaneous Mixture of Delayed Sources Using High‐Order Taylor Approximation 下载免费PDF全文
Wei Zhao Zhigang Yuan Yuehong Shen Yufan Cao Yimin Wei Pengcheng Xu Wei Jian 《ETRI Journal》2015,37(4):727-735
This paper deals with the problem of blind source separation (BSS), where observed signals are a mixture of delayed sources. In reference to a previous work, when the delay time is small such that the first‐order Taylor approximation holds, delayed observations are transformed into an instantaneous mixture of original sources and their derivatives, for which an extended second‐order blind identification (SOBI) approach is used to recover sources. Inspired by the results of this previous work, we propose to generalize its first‐order Taylor approximation to suit higher‐order approximations in the case of a large delay time based on a similar version of its extended SOBI. Compared to SOBI and its extended version for a first‐order Taylor approximation, our method is more efficient in terms of separation quality when the delay time is large. Simulation results verify the performance of our approach under different time delays and signal‐to‐noise ratio conditions, respectively. 相似文献
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尾矿库水位是影响坝体安全的重要因素之一,针对库水位变化对尾矿坝稳定性的影响问题,建立考虑超孔隙水压力作用下的流固耦合数学模型,利用有限差分程序FLAC3D进行数值求解.模拟了某尾矿库在不同库水位时的稳定性,得出库水位的升高对尾矿坝影响规律.即随着库水位的升高,尾矿坝浸润线升高,安全系数降低,尾矿坝坝体中部的剪应力逐渐增... 相似文献
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旨在高值化利用青刺果榨油后副产物青刺果粕中的蛋白质,以青刺果粕为原料,提取青刺果蛋白并制备蛋白酶解物,采用活菌吸附法联合反相高效液相色谱(RP-HPLC)从蛋白酶解物中筛选出抗菌肽组分,评价其抑菌活性,并对抑菌活性最好的组分进行稳定性分析。结果表明:筛选出的3个抗菌肽组分(F1、F2和F3)中,F2组分抑菌活性最好,当其质量浓度为10 mg/mL时对金黄色葡萄球菌和大肠杆菌的抑菌活性分别达到45.5%和39.1%;抗菌肽组分F2抑菌活性随温度升高和盐溶液浓度增加均降低,最适pH为6.0,在酸性环境中极不稳定,对酸性蛋白酶、碱性蛋白酶、胃蛋白酶和胰蛋白酶的耐受性均较差,对中性蛋白酶耐受性较好。综上,青刺果粕中的蛋白酶解物具有抑菌活性,具有开发青刺果抗菌肽的潜力。 相似文献
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Cool release process of phase change material (PCM) includes the dissolution process of the PCM. Experimental research on the cool release process in a new gas-hydrate cool storage system is performed in this paper. In the system, the inner-heat exchange/outer-crystallization technology and the integrated condenser/evaporator structure design were adopted. The influences of different proportions of calcium hypochlorite or benzenesulfonic acid sodium salt on the dissolution process are studied. The results show that the instantaneous dissolution rate is close to twice as the corresponding instantaneous formation rate of gas-hydrate, and the cold energy release rate, i.e. energy release per unit time, is obviously higher than the corresponding cold energy storage rate at different conditions, which is mainly due to the heat transfer temperature difference of the discharging (release) and charging (store) processes. Both the charging and the discharging processes are simultaneously dominated by the heat transfer and the mass transfer processes. However, as to the dissolution (discharging) process of the gas-hydrate by heating, the effect of the heat transfer process is the main influence factor. The temperature difference between the heating medium and the gas-hydrate in the discharging process, which is larger than that between the cooling medium and the gas-hydrate in the charging process, makes a higher cold energy release rate compared with the cold energy storage rate. The results also indicate that the dissolution rate of gas-hydrate is accelerated, and the cold energy release rate of the cool storage system is increased by adding reasonable proportions of the additives. 相似文献