Adaptive Control with Quantized Inputs Processed by Lipschitz Logarithmic Quantizer

International Journal of Control, Automation and Systems - In this paper, the design of adaptive control for a class of control systems with quantized inputs is investigated. According to the...     

A distributed learning based sentiment analysis methods with Web applications

World Wide Web - The main challenge of using deep learning (DL) for sentiment analysis tasks is that insufficient data leads to a decrement in classification accuracy. In addition, privacy issues...     

直流配电系统接口换流器虚拟同步发电机自适应惯性控制策略

直流配电网具有低惯性弱阻尼特征,负荷投切、分布式能源出力波动等扰动,会对直流母线电压造成严重影响.类比交流系统中的虚拟同步发电机控制,文章提出了基于电压-电流下垂控制的直流虚拟同步发电机自适应惯性控制策略;建立了直流虚拟同步发电机小信号模型,推导出直流母线电压与直流侧输出电流之间的传递函数;根据直流母线电压暂态振荡特征...     

含缓存池的立体车库并行存车方案设计与分析

为了缓解高峰期停车难、排队等待时间长和立体车库存车效率低的问题,提出一种具有缓存功能的立体车库。首先,充分利用立体车库底层空间设计子母车缓存池存车方案,通过缓存池的连续搬运工作提高存取车效率。由于车库各层均布置有一辆母车,提出多层循环车位分配策略,实现车库多层母车并行存车功能,并通过分析多个存车请求下立体车库的工作时序特征计算立体车库并行存车效率。其次,基于顾客存车流程建立M/M/n存车排队模型,并采用排队理论分析不同顾客到达速率下升降货梯平均利用率,不同升降货梯数量下顾客存车平均排队的时间、队长和需要等待的概率。最后,结合实际车辆参数、车库结构尺寸和子母车搬运系统的运动参数,并基于占地面积合理设计存车缓存池容量,对比分析缓存池作用前后的顾客存车指标,验证了缓存池能够大幅降低顾客存车等待时间。结果表明：立体车库系统在进行5辆车并行存车状态下,比传统的堆垛机式立体车库存车效率提升39%;顾客到达速率为75辆/h,设置存车的子车缓存池容量为4,可节省顾客约47.8%的平均排队时间。因此,该含有缓存池的立体车库并行存车方案能显著提高存车效率,同时降低顾客等待时间,可进一步满足顾客存车需求。     

对执行氯化锌新标准的体会

本文简述了氯化锌新标准:HG2323—92《工业氯化锌》,并就如何贯彻执行这一标准谈了一些体会和看法。     

Printing Semiconductor–Insulator Polymer Bilayers for High‐Performance Coplanar Field‐Effect Transistors

Source–semiconductor–drain coplanar transistors with an organic semiconductor layer located within the same plane of source/drain electrodes are attractive for next‐generation electronics, because they could be used to reduce material consumption, minimize parasitic leakage current, avoid cross‐talk among different devices, and simplify the fabrication process of circuits. Here, a one‐step, drop‐casting‐like printing method to realize a coplanar transistor using a model semiconductor/insulator [poly(3‐hexylthiophene) (P3HT)/polystyrene (PS)] blend is developed. By manipulating the solution dewetting dynamics on the metal electrode and SiO₂ dielectric, the solution within the channel region is selectively confined, and thus make the top surface of source/drain electrodes completely free of polymers. Subsequently, during solvent evaporation, vertical phase separation between P3HT and PS leads to a semiconductor–insulator bilayer structure, contributing to an improved transistor performance. Moreover, this coplanar transistor with semiconductor–insulator bilayer structure is an ideal system for injecting charges into the insulator via gate‐stress, and the thus‐formed PS electret layer acts as a “nonuniform floating gate” to tune the threshold voltage and effective mobility of the transistors. Effective field‐effect mobility higher than 1 cm² V^?1 s^?1 with an on/off ratio > 10⁷ is realized, and the performances are comparable to those of commercial amorphous silicon transistors. This coplanar transistor simplifies the fabrication process of corresponding circuits.     

Organic-semiconductor: Polymer-electret blends for high-performance transistors

As compared with polymer semiconductors, solution-processed small-molecule semiconductors usually have poorer film-formation properties, which induces wide variations in device performance in terms of mobility and threshold voltage, thus severely limiting their commercial applications. In this work, we propose an easily accessible method to improve the performance and reduce the variability of small-molecule organic field-effect transistors (OFETs) by blending organic semiconductors with an insulator polymer, which is subsequently post-treated by gate stress to generate an electret. By blending the organic semiconductor 2,7-didodecyl[1]benzothieno[3,2-b][1]benzothiophene (C₁₂-BTBT) with the insulator polystyrene, uniform transport layers with vertically phase segregated morphology are obtained, from which the mobility and threshold voltage of OFETs are largely manipulated. The OFETs exhibit field-effect mobilities as high as 7.5 cm²·V^?1·s^?1 with an on/off ratio exceeding 10⁶ in ambient conditions. This double-layer structure provides an appropriate architecture for applying gate-stress to inject charges into the insulating layer, forming an electret. The generation of the electret is thermally accelerated and thus can be easily realized under moderate gate-stress at elevated temperature (e.g., 60 °C). After cooling, the electret layer serves as a floating-gate, which not only continuously tunes the threshold voltage and field-effect mobility, but also helps minimize the contact resistances and optimize the subthreshold swing. As an application of this method, a digital inverter is built and its performance is optimized via in situ tuning of its individual transistors.

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18.9% Efficiency Ternary Organic Solar Cells Enabled by Isomerization Engineering of Chlorine-Substitution on Small Molecule Donors

Ternary organic solar cells (OSCs) represent an efficient and facile strategy to further boost the device performance. However, the selection criteria and rational design of the third guest small molecule (SM) material still remain less understood. In this study, two new SM donor isomers, with α-chlorinated thiophene (αBTCl) and β-chlorinated thiophene (βBTCl) as side chains, are systematically designed, synthesized and incorporated as a third component in PM6:L8-BO binary blends. It is noticed that introducing the SM donors guest has extended the absorption of photo-active layer, induced desired component distribution vertically with enhanced crystallinity and reduced recombination process, leading to increased short-circuit current (J_SC) and improved fill factor. Moreover, due to the synergetic suppressed nonradiative loss and preferable morphology, the ternary OSCs feature improves open-circuit voltage (V_OC). Consequently, an impressive champion power conversion efficiency of 18.96% and 18.55% is achieved by αBTCl-based and βBTCl-based ternary OSCs, respectively. Furthermore, a record efficiency of 17.46% is obtained with a 330 nm thickness of αBTCl-based ternary OSCs. This study demonstrates that molecular isomerization can be a promising design approach for SM donors to construct high-performance ternary OSCs with simultaneous enhancement of all photovoltaic parameters.     

计及暂态频率稳定约束的同步惯量经济价值评估

高渗透率新能源接入系统后,保障系统具有充足的在线惯量是维持系统频率安全稳定的关键,同时建立惯性辅助服务市场是解决该问题的有效手段。因此,将同步惯性响应纳入有偿服务,搭建考虑系统最低同步惯量需求约束的定价出清模型,并提出离散变量松弛化的方法,将出清模型转化为凸优化问题。然后,基于边际成本定价法和拉格朗日对偶原理,以最低同步惯量需求约束对应的影子价格来评估其经济价值,为惯性服务定价。最后,以改进的IEEE 39节点系统和IEEE 118节点系统为例,对同步惯量影子价格的存在机理、数值影响因素以及同步机组收益进行分析讨论。结果表明,含高比例新能源系统具有建设惯性辅助服务市场的必要性和迫切性。所提方法和仿真结论为惯性服务市场化提供了参考性意见。     

野野村放线菌ATCC 39727利用短链羧酸合成细胞脂肪酸

本实验对野野村放线菌ATCC 39727利用外源添加的不同短链羧酸为起始物合成细胞脂肪酸的能力进行了研究,结果表明,该菌优先利用异丁酰CoA、丁酰CoA和丙酰CoA为细胞脂肪酸合成起始物,但利用3-甲基丁酰CoA为脂肪酸合成起始物的能力较差.细胞脂肪酸中检出了以2-甲基丁酰CoA为起始物合成的anteiso-C17:0...