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51.
针对深衰落稀疏多径信道下多进制相移键控(Multiple Phase Shift Keying,MPSK)信号的盲均衡问题,提出了一种l0-范数约束的分数间隔稀疏自适应双模式盲均衡算法.该算法借鉴传统的分数间隔双模式盲均衡算法思想,结合稀疏自适应滤波理论,首先利用l0-范数对均衡器抽头系数进行稀疏性约束,构造出一种l0-范数约束的分数间隔双模式最小均方误差代价函数,然后依据梯度下降法推导出盲均衡器抽头系数更新公式,并对迭代步长进行归一化和比例系数化.理论分析和仿真实验表明,与基于门限稀疏化的盲均衡算法、基于分数阶范数的盲均衡算法及分数间隔双模式盲均衡算法相比,本文所提算法在保证较快收敛速度的前提下,能有效降低剩余符号间干扰.本文设计的盲均衡算法为水声通信系统中接收方恢复出发送信号,提供了一种快速有效的方法. 相似文献
52.
双模式混合驱动装置电机参数匹配 总被引:1,自引:0,他引:1
对双模式混合驱动装置进行了特性分析,并研究了其电机转速、转矩、功率匹配的规律,得到了双模式混合驱动装置电机参数匹配方法。基于两个电机的转速转矩与混合驱动装置的输入输出转速、转矩的关系,以及混合驱动装置的功率分流特性,对电机的转速、转矩和功率匹配进行了研究。最后得到了电机参数与发动机参数、混合驱动装置结构参数及输出特性的... 相似文献
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54.
Abstract An approach to suppress the harmonic responses in a dual-mode circular ring resonator bandpass filter is presented. Feed lines with one-sided coupling arms are suitably relocated around the ring resonator to introduce phase interference between two degenerate modes for simultaneously suppressing the second and third harmonics. Three open loop resonators at the rim of the ring are adopted to further suppress the second harmonic. By fabricating on a FR4 glass-epoxy base, this approach is demonstrated to have effectiveness in broadening the filter's rejection band in both simulations and measurements without affecting the fundamental response or increasing the device size. 相似文献
55.
This article presents a novel induction heating power supply. The power supply is based on an auxiliary active edge resonant zero-current soft-switching technique. It consists of single-ended push–pull series load resonant inverter. The proposed inverter is cost effective for high-frequency induction heating consumer appliances. The new multi-resonant high-frequency inverter with series load resonance and edge resonance can regulate its high-frequency output power under the constant-frequency zero-current soft-switching commutation principle on the basis of an asymmetrical pulse-width modulation control scheme. The brand-new consumer induction heating product is evaluated and discussed on the basis of simulation and experimental results. To extend zero-current soft-switching operation ranges under a low-power setting as well as improve efficiency, the high-frequency pulse-density modulation strategy is demonstrated for a high-frequency soft-switching inverter. Its practical effectiveness of induction heating power supply is substantially proved from an induction heating application point of view. 相似文献
56.
A fifth/seventh order dual-mode OTA-C complex filter for global navigation satellite system receivers is implemented in a 0.18μm CMOS process.This filter can be configured as the narrow mode of a 4.4 MHz bandwidth center at 4.1 MHz or the wide mode of a 22 MHz bandwidth center at 15.42 MHz.A fully differential OTA with source degeneration is used to provide sufficient linearity.Furthermore,a ring CCO based frequency tuning scheme is proposed to reduce frequency variation.The measured results show that in narrow-band mode the image rejection ratio(IMRR)is 35 dB,the filter dissipates 0.8 mA from the 1.8 V power supply,and the out-of-band rejection is 50 dB at 6 MHz offset.In wide-band mode,IMRR is 28 dB and the filter dissipates 3.2 mA.The frequency tuning error is less than±2%. 相似文献
57.
《分离科学与技术》2012,47(17):2756-2764
Unlike other members of the leguminous family that are generally used as food, Rhynchosia volubilis, a small soybean with a black seed coat, is used as a folk medicine in Korea. Using an on-line high performance liquid chromatography-2,2?-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) radical cation screening system, one peak in the ethyl acetate fraction exhibited outstanding antioxidant capacity. To purify and determine the antioxidant compounds associated with this peak, we developed a centrifugal partition chromatography (CPC) method. The ethyl acetate fraction (500 mg) was subjected to CPC using a two-phase solvent system of n-hexane–ethyl acetate–ethanol–water (0.1:8:2:7, v/v) with a dual-mode CPC (descending-ascending order) in a bid to separate glycitin (3.1 mg), daidzin (14.4 mg), 6??-O-acetyl genistin (6.9 mg), 6??-O-acetyl daidzin (5.3 mg), and a mixture of epicatechin and genistin. The mixture was further separated through solid-phase extraction to yield epicatechin (6.8 mg) and genistin (23.5 mg), respectively. Structural identification of the R. volubilis flavonoids was performed by NMR and ESI-MS. 相似文献
58.
Xiaohui Guo Weiqiang Hong Yunong Zhao Tong Zhu Long Liu Hongjin Li Ziwei Wang Dandan Wang Zhihong Mai Tianxu Zhang Jinyang Yang Fengzhe Zhang Yun Xia Qi Hong Yaohua Xu Feng Yan Ming Wang Guozhong Xing 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(1):2205316
Recently, flexible stretchable sensors have been gaining attention for their excellent adaptability for electronic skin applications. However, the preparation of stretchable strain sensors that achieve dual-mode sensing while still retaining ultra-low detection limit of strain, high sensitivity, and low cost is a pressing task. Herein, a high-performance dual-mode stretchable strain sensor (DMSSS) based on biomimetic scorpion foot slit microstructures and multi-walled carbon nanotubes (MWCNTs)/graphene (GR)/silicone rubber (SR)/Fe3O4 nanocomposites is proposed, which can accurately sense strain and magnetic stimuli. The DMSSS exhibits a large strain detection range (≈160%), sensitivity up to 100.56 (130–160%), an ultra-low detection limit of strain (0.16% strain), and superior durability (9000 cycles of stretch/release). The sensor can accurately recognize sign language movement, as well as realize object proximity information perception and whole process information monitoring. Furthermore, human joint movements and micro-expressions can be monitored in real-time. Therefore, the DMSSS of this work opens up promising prospects for applications in sign language pose recognition, non-contact sensing, human-computer interaction, and electronic skin. 相似文献
59.
Tian Liu Guangyu Wu Jiejun Cheng Qing Lu Yanjie Yao Zhenjing Liu Dongchen Zhu Juan Zhou Jianrong Xu Jun Zhu Dannong He 《Nano Research》2016,9(2):473-489
A universal platform with Mn doping and hyaluronic acid (HA) modification, based on mesoporous silica (mSiO2), was designed and used as a basic multifunctional material with magnetic resonance (MR) imaging. Furthermore, we added flexible functions through the addition of functional molecules. Specially, two typical compounds, hydrophobic perfluorooctyl bromide (PFOB) and hydrophilic doxorubicin (DOX), were loaded into the channels to obtain PFOB@Mn@mSiO2@HA (PMMH) or DOX@Mn@mSiO2@HA (DMMH) nanoparticles for dual-mode imaging or imaging and therapy, respectively. The PMMH and DMMH nanoparticles were highly targeted to the lymph system in vitro and in vivo. MR and ultrasound imaging of PMMH nanoparticles were performed in the lymph system, while MR imaging and chemotherapy of DMMH nanoparticles was used to detect cancer. These results showed that both PMMH and DMMH nanoparticles can be designed with high lymph targeting efficiency. PMMH nanoparticles are a dual-mode contrast agent for both ultrasound and MR imaging for the lymph system and DMMH nanoparticles are powerful agents for the combined diagnosis and therapy of cancer in vivo. 相似文献
60.
基于多尺度小波包变换良好的时频局部分析能力,对一类非高斯噪声——双模噪声的统计特性进行研究。理论分析和仿真表明,小波包检测系统不仅具有计算量小、算法比较简单和实时性较强的特点,而且实现了将非高斯噪声(双模噪声)转化为简单的高斯噪声来处理。 相似文献