Conjugated polymers have received considerable attentions over the past years due to their large-area potential applications via low-cost solution processing. Improving crystallinity of conjugated polymer molecules in...Conjugated polymers have received considerable attentions over the past years due to their large-area potential applications via low-cost solution processing. Improving crystallinity of conjugated polymer molecules in solution-processed thin films is crucial for their efficient charge transport and thus high performance optoelectronic devices. Herein, with diketopyrrolopyrrole-quaterthiophene （PDQT） copo/ymer as an example, it is found that by simply reducing the solution concentration for spincoating meanwhile with the assistance of post-annealing, significantly enhanced film crystallinity with formation of typical single crystalline domains is obtained, which benefits from the enough space for better molecular assembly especially at the semiconductor/dielectric interface. High performance polymer transistors and phototransistors were finally constructed based on the optimal lowconcentration （2 mg/mL） spin-coated PDQT films （～12 nm）, which giving a high charge carrier mobility of 2.28 cm2 V-1 s-1 and a photoresponse on/off ratio of 2.1 ×107 at VG = 0 V under white light irradiation of 6mW/cm2. The results suggest that the bright future of PDQT crystalline films for large-area flexible integrated optoelectronic devices and the application of effective low-concentration processing approach in solution-processed organic electronics with reduced material waste.展开更多
随着可再生能源接入电网比例的逐步增大,热力发电厂需要应对更加频繁、更大范围的负荷变化,给电厂的高阶大惯性过热汽温过程的控制带来严峻的挑战。为此,文中针对一类高阶大惯性过热汽温过程,提出一种基于相位补偿的自抗扰控制(phase co...随着可再生能源接入电网比例的逐步增大,热力发电厂需要应对更加频繁、更大范围的负荷变化,给电厂的高阶大惯性过热汽温过程的控制带来严峻的挑战。为此,文中针对一类高阶大惯性过热汽温过程,提出一种基于相位补偿的自抗扰控制(phase compensation based active disturbance rejection control,PC-ADRC)方法。首先,阐述过热汽温系统的工作原理和控制难点。然后,采用低频近似法详细推导相位补偿(phase compensation,PC)网络模型,提出采用PC网络对模型动态特性进行补偿,得到等效降阶模型的简化思路。为便于工程应用,给出PC-ADRC系统的简单实现方法和等效模型分析。最后,对PC-ADRC系统的稳定性和鲁棒性进行研究。理论分析和仿真结果表明,所提出的PC-ADRC系统能有效提升高阶过程控制系统的鲁棒性和快速响应能力。展开更多
针对阵列信号处理领域中的超分辨子空间类算法需计算阵列输出的协方差、协方差矩阵的特征分解及进行谱峰搜索得到波达方向(Direction of Arrival,DOA)估计,计算量较大则实际应用可能受限,提出了一种低计算复杂度的新颖的无需谱峰搜索的...针对阵列信号处理领域中的超分辨子空间类算法需计算阵列输出的协方差、协方差矩阵的特征分解及进行谱峰搜索得到波达方向(Direction of Arrival,DOA)估计,计算量较大则实际应用可能受限,提出了一种低计算复杂度的新颖的无需谱峰搜索的DOA估计算法。通过Nyström方法得到逼近的信号子空间,避免了直接对所有阵列输出计算协方差及对其特征分解从而降低了运算量。通过逼近的信号子空间构建低阶的关于DOA的特征多项式方程,对此低阶多项式方程求根得到DOA估计进一步降低了运算量,且不同于现有的DOA估计求根算法。理论分析和仿真结果表明,所提算法有着良好的估计精度及较低的计算复杂度。展开更多
基金financial support from the Ministry of Science and Technology of China (Nos. 2017YFA0204503, 2016YFB0401100)the National Natural Science Foundation of China (Nos. 51725304, 91433115, 51633006, 51733004)+1 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences (No. XDB12030300)National program for support of top-notch young professionals
文摘Conjugated polymers have received considerable attentions over the past years due to their large-area potential applications via low-cost solution processing. Improving crystallinity of conjugated polymer molecules in solution-processed thin films is crucial for their efficient charge transport and thus high performance optoelectronic devices. Herein, with diketopyrrolopyrrole-quaterthiophene （PDQT） copo/ymer as an example, it is found that by simply reducing the solution concentration for spincoating meanwhile with the assistance of post-annealing, significantly enhanced film crystallinity with formation of typical single crystalline domains is obtained, which benefits from the enough space for better molecular assembly especially at the semiconductor/dielectric interface. High performance polymer transistors and phototransistors were finally constructed based on the optimal lowconcentration （2 mg/mL） spin-coated PDQT films （～12 nm）, which giving a high charge carrier mobility of 2.28 cm2 V-1 s-1 and a photoresponse on/off ratio of 2.1 ×107 at VG = 0 V under white light irradiation of 6mW/cm2. The results suggest that the bright future of PDQT crystalline films for large-area flexible integrated optoelectronic devices and the application of effective low-concentration processing approach in solution-processed organic electronics with reduced material waste.
文摘随着可再生能源接入电网比例的逐步增大,热力发电厂需要应对更加频繁、更大范围的负荷变化,给电厂的高阶大惯性过热汽温过程的控制带来严峻的挑战。为此,文中针对一类高阶大惯性过热汽温过程,提出一种基于相位补偿的自抗扰控制(phase compensation based active disturbance rejection control,PC-ADRC)方法。首先,阐述过热汽温系统的工作原理和控制难点。然后,采用低频近似法详细推导相位补偿(phase compensation,PC)网络模型,提出采用PC网络对模型动态特性进行补偿,得到等效降阶模型的简化思路。为便于工程应用,给出PC-ADRC系统的简单实现方法和等效模型分析。最后,对PC-ADRC系统的稳定性和鲁棒性进行研究。理论分析和仿真结果表明,所提出的PC-ADRC系统能有效提升高阶过程控制系统的鲁棒性和快速响应能力。
文摘针对阵列信号处理领域中的超分辨子空间类算法需计算阵列输出的协方差、协方差矩阵的特征分解及进行谱峰搜索得到波达方向(Direction of Arrival,DOA)估计,计算量较大则实际应用可能受限,提出了一种低计算复杂度的新颖的无需谱峰搜索的DOA估计算法。通过Nyström方法得到逼近的信号子空间,避免了直接对所有阵列输出计算协方差及对其特征分解从而降低了运算量。通过逼近的信号子空间构建低阶的关于DOA的特征多项式方程,对此低阶多项式方程求根得到DOA估计进一步降低了运算量,且不同于现有的DOA估计求根算法。理论分析和仿真结果表明,所提算法有着良好的估计精度及较低的计算复杂度。
