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961.
Experimental studies to reveal the cooperative relationship between spin, energy, and polarization through intermolecular charge‐transfer dipoles to harvest nonradiative triplets into radiative singlets in exciplex light‐emitting diodes are reported. Magneto‐photoluminescence studies reveal that the triplet‐to‐singlet conversion in exciplexes involves an artificially generated spin‐orbital coupling (SOC). The photoinduced electron parametric resonance measurements indicate that the intermolecular charge‐transfer occurs with forming electric dipoles (D+?→A??), providing the ionic polarization to generate SOC in exciplexes. By having different singlet‐triplet energy differences (ΔEST) in 9,9′‐diphenyl‐9H,9′H‐3,3′‐bicarbazole (BCzPh):3′,3′″,3′″″‐(1,3,5‐triazine‐2,4,6‐triyl)tris(([1,1′‐biphenyl]‐3‐carbonitrile)) (CN‐T2T) (ΔEST = 30 meV) and BCzPh:bis‐4,6‐(3,5‐di‐3‐pyridylphenyl)‐2‐methyl‐pyrimidine (B3PYMPM) (ΔEST = 130 meV) exciplexes, the SOC generated by the intermolecular charge‐transfer states shows large and small values (reflected by different internal magnetic parameters: 274 vs 17 mT) with high and low external quantum efficiency maximum, EQEmax (21.05% vs 4.89%), respectively. To further explore the cooperative relationship of spin, energy, and polarization parameters, different photoluminescence wavelengths are selected to concurrently change SOC, ΔEST, and polarization while monitoring delayed fluorescence. When the electron clouds become more deformed at a longer emitting wavelength due to reduced dipole (D+?→A??) size, enhanced SOC, increased orbital polarization, and decreased ΔEST can simultaneously occur to cooperatively operate the triplet‐to‐singlet conversion.  相似文献   
962.
本文提出了一种基于新的优化修正函数的模糊控制方法,该方法根据误差E和误差变化EC修改规则调整因子α,不仅体现了按误差大小自动调节误差E对控制作用的权重,而且也考虑到误差变化EC在系统的各个运行阶段对控制性能有不同的影响,从而使该模糊控制器具有更好的适应非线性、时变、不确定性等复杂难控对象的能力.最后利用MATLAB的SIMULINK进行仿真研究,结果表明,该控制器具有较强的抗干扰能力和鲁棒性,有较好的动、静态控制精度.  相似文献   
963.
TRIP systems are tools for visualization and animation. They are based on a constraint-based model of bi-directional translation between abstract data and pictorial data. Using these systems, programmers can visualize abstract data, and animate various algorithms and processes, simply by providing a declarative mapping rule. This paper presents this model for visualization and animation, focusing on the use of constraints, and also presents the TRIP systems with examples of visualization and animation.  相似文献   
964.
Recently, adjustable-speed ac drive systems have been employed successfully for blowers, pumps, table rollers, etc., in steel plants instead of the more conventional dc drives. In processing lines many drives require speed and tension control. To confirm the suitability of an ac drive for tension control, the tension reel of an existing pilot processing line has been equipped with an adjustable-speed ac drive. An ac drive system for tension reel control, its characteristics, and performance are described and compared with a dc tension control.  相似文献   
965.
This paper presents supervisory control of a total molten-metal pouring system to improve the productivity of the factory, the safety of workers, and the quality of the product. Through the pouring processes model, a forward tilting control input was calculated by an adaptive feedforward control system to hold the liquid in the sprue cup at a constant level considering the change effected by the accumulating slag in the ladle. A backward tilting input was obtained by means of the hybrid shape approach applied to suppress the slosh. The supervisory control system reasonably switches from the forward tilting motion to the backward tilting motion by using model predictive control to achieve the accurate poured quantity. The validity of the proposed total control system was demonstrated through experiments.  相似文献   
966.
基于鞍点搜索的粘连对象图像分割方法   总被引:1,自引:0,他引:1       下载免费PDF全文
汪一聪  陈恳 《计算机工程》2009,35(10):203-205
针对图像中不规则形状物体接触的分割问题,提出一种采用Hessian矩阵来判断分割点(即鞍点)进行粘连对象分割的方法。根据对图像进行腐蚀操作得到的三维地貌图,结合鞍点的数学特性,运用Hessian矩阵的特征值对鞍点进行搜索定位,沿经过鞍点的最大梯度路径分割粘连对象。与目前已有的几种分割算法相比,该方法具有算法简捷、分割效果好以及易于实现的特点。  相似文献   
967.
We propose a proof system for reasoning on certain specifications of secure authentication systems. For this purpose, a new logic, sequence-indexed linear-time temporal logic (SLTL), is obtained semantically from standard linear-time temporal logic (LTL) by adding a sequence modal operator that represents a sequence of symbols. By this sequence modal operator, we can appropriately express message flows between clients and servers and states of servers in temporal reasoning. A Gentzen-type sequent calculus for SLTL is introduced, and the completeness and cut-elimination theorems for it are proved. SLTL is also shown to be PSPACE-complete and embeddable into LTL.  相似文献   
968.
Proteins secreted from specific cancer cells have a high potential for use as tumor markers. We identified secreted proteins produced by 15 different carcinoma cell lines grown in serum-free medium using MS/MS. Proneurotensin/neuromedin N (proNT/NMN) was found in conditioned medium from four of seven small cell lung carcinoma cell lines but not from eight nonsmall cell lung carcinoma cell lines. These results indicate proNT/NMN has potential as a specific tumor marker of small cell lung carcinoma.  相似文献   
969.
PC energy use is a growing cost to enterprises, with most machines remaining fully powered on, even while idle, for most of the time. The Network Connectivity Proxy maintains network presence for PCs but lets them sleep while idle, thus saving energy and reducing total cost of ownership.  相似文献   
970.
调度自动化系统EMS应用软件在地区电网调度中的运用   总被引:4,自引:0,他引:4  
能量管理系统EMS(Energy Management System)是以计算机为基础的现代电力系统的综合自动化系统,主要针对发电和输电系统,用于大区级电网和省级电网的调度中心.本文详细阐述了调度自动化系统EMS应用软件的组成、基本功能和用途,并以吉安地区电网为例,介绍了其在电网调度自动化系统中的具体应用,为地区电网调度提供了可靠的科学分析手段。  相似文献   
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