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31.
通过求解Poisson方程,对热平衡态金属:p-n-CdTeSchotky势垒薄膜太阳能电池进行计算机数值模拟。嵌入的p型层增大传统金属:n-CdTe结的有效Schotky势垒高度与p型层厚度、掺杂浓度以及n-CdTe本底电阻率有依赖关系。最后讨论嵌入p型层增强CdTeSchotky势垒太阳能电池对光生载流子的收集作用。 相似文献
32.
Hsin‐Te Lue Ming‐Gang Wen Hsu‐Yung Cheng Kuo‐Chin Fan Chih‐Wei Lin Chih‐Chang Yu 《ETRI Journal》2010,32(5):729-739
Due to the rapid development of mobile devices equipped with cameras, instant translation of any text seen in any context is possible. Mobile devices can serve as a translation tool by recognizing the texts presented in the captured scenes. Images captured by cameras will embed more external or unwanted effects which need not to be considered in traditional optical character recognition (OCR). In this paper, we segment a text image captured by mobile devices into individual single characters to facilitate OCR kernel processing. Before proceeding with character segmentation, text detection and text line construction need to be performed in advance. A novel character segmentation method which integrates touched character filters is employed on text images captured by cameras. In addition, periphery features are extracted from the segmented images of touched characters and fed as inputs to support vector machines to calculate the confident values. In our experiment, the accuracy rate of the proposed character segmentation system is 94.90%, which demonstrates the effectiveness of the proposed method. 相似文献
33.
Ge Zhang Xuewu Ou Chunyu Cui Jianmin Ma Jinghai Yang Yongbing Tang 《Advanced functional materials》2019,29(2)
Dual‐ion batteries (DIBs) have attracted much attention due to their advantages of low cost and especially environmental friendliness. However, the capacities of most DIBs are still unsatisfied (≈100 mAh g?1) ascribed to the limited capacity of anions intercalation for conventional graphite cathode. In this study, 3D porous microcrystalline carbon (3D‐PMC) was designed and synthesized via a self‐templated growth approach, and when used as cathode for a DIB, it allows both intercalation and adsorption of anions. The microcrystalline carbon is beneficial to obtain capacity originated from anions intercalation, and the 3D porous structure with a certain surface area contributes to anions adsorption capacity. With the synergistic effect, this 3D‐PMC is utilized as cathode and tin as anode for a sodium‐based DIB, which has a high capacity of 168.0 mAh g?1 at 0.3 A g?1, among the best values of reported DIBs so far. This cell also exhibits long‐term cycling stability with a capacity retention of ≈70% after 2000 cycles at a high current rate of 1 A g?1. It is believed that this work will provide a strategy to develop high‐performance cathode materials for DIBs. 相似文献
34.
钨化学气相淀积因为其在接触孔/通孔填充中出色的台阶覆盖能力而在半导体工业中被广泛应用,在量产中经常会出现监控片的方块电阻均匀性超规格。本文主要研究了加热器、气体输送、氟化铝、机械传片定位、真空微漏等因素对方块电阻均匀性的影响,特别周期性等离子清洗产生的氟化铝对晶圆边缘的抑制反应是影响腔体维护频率的主要原因,并提出改善均匀性的有效办法。 相似文献
35.
Implementation of depth‐based routing and its enhancement in AquaSim–Next Generation for underwater wireless sensor networks 下载免费PDF全文
Mohsin Jafri Simonetta Balsamo Andrea Marin Robert Martin 《International Journal of Communication Systems》2018,31(12)
In the last decade, underwater wireless sensor networks have been widely studied because of their peculiar aspects that distinguish them from common terrestrial wireless networks. Their applications range from environmental monitoring to military defense. The definition of efficient routing protocols in underwater sensor networks is a challenging topic of research because of the intrinsic characteristics of these networks, such as the need of handling the node mobility and the difficulty in balancing the energy consumed by the nodes. Depth‐based routing protocol is an opportunistic routing protocol for underwater sensor networks, which provides good performance both under high and low node mobility scenarios. The main contribution of our work is presenting a novel simulator for studying depth‐based routing protocol and its variants as well as novel routing protocols. Our simulator is based on AquaSim–Next Generation, which is a specialized tool for studying underwater networks. With our work, we improve the state of the art of underwater routing protocol simulators by implementing, among other features, a detailed cross‐layer communication and an accurate model of the operational modes of acoustic modem and their energy consumption. The simulator is open source and freely downloadable. Moreover, we propose a novel and completely distributed routing protocol, named residual energy–depth‐based routing. It takes into account the residual energy at the nodes' batteries to select the forwarder nodes and improve the network lifetime by providing a more uniform energy consumption among them. We compare its performance with that of depth‐based routing protocol and a receiver‐based routing protocol implementing a probabilistic opportunistic forwarding scheme. 相似文献
36.
在通用协议栈概念的基础上,引入集中式协议栈管理和分散式分层协议管理相结合的新的重配置控制管理功能,提出一种改进的、基于组件的分层可重配置协议栈模型,给出其协议栈重配置方法,详尽阐述了利用面向对象方法实现协议组件分解、合成、替换和通信的软件技术。 相似文献
37.
利用固相反应法在硅片上制备硅酸锌发光薄膜及表征 总被引:1,自引:0,他引:1
采用与硅集成工艺相兼容的固相反应方法在硅衬底上制备了未经掺杂及掺锰的硅酸锌薄膜 .XRD测试和UV - Vis吸收谱测试证明在高于 880℃的温度下热处理 ,可以获得结晶状态很好的硅酸锌薄膜 .光致发光光谱分析表明 ,未掺杂的薄膜在紫外波段有较弱的发射 ,而掺锰的硅酸锌薄膜在可见光波段有很强的光致发射 .由于硅酸锌薄膜在高温下非常稳定 ,可以与硅集成电路工艺兼容 ,而且发光强度高 ,因此在制作硅基光电集成器件方面有非常大的应用前景 相似文献
38.
With the advent of the Internet‐of‐Things paradigm, the amount of data production has grown exponentially and the user demand for responsive consumption of data has increased significantly. Herein, we present DART, a fast and lightweight stream processing framework for the IoT environment. Because the DART framework targets a geospatially distributed environment of heterogeneous devices, the framework provides (1) an end‐user tool for device registration and application authoring, (2) automatic worker node monitoring and task allocations, and (3) runtime management of user applications with fault tolerance. To maximize performance, the DART framework adopts an actor model in which applications are segmented into microtasks and assigned to an actor following a single responsibility. To prove the feasibility of the proposed framework, we implemented the DART system. We also conducted experiments to show that the system can significantly reduce computing burdens and alleviate network load by utilizing the idle resources of intermediate edge devices. 相似文献
39.
Sunyeong Jang Hyungju Seo Hojin Kim Hyoyoung Kim Jongsung Ahn Hyunjeong Cho Sunghie Hong Seunghwa Lee Taewoong Na 《Molecules (Basel, Switzerland)》2022,27(14)
A method was developed for the rapid and quantitative analysis of 30 veterinary drugs belonging to 17 classes (amphenicols (1), anthelmintics (1), cephalosporins (4), coccidiostats (1), lincosamides (1), macrolide (1), nitroimidazole (1), penicillins (3), phenylhydrazines (1), polypeptides (1), pyrethrins (1), quinolones (5), sulfonamides (3), tetracycline (3), neuroleptic agents (1), triazene trypanocidal agents (1), other. (1)) in feeds. The proposed method with a modified Quick Polar Pesticides (QuPPe) sample preparation was validated for the determination of 30 veterinary drugs in feed samples by liquid chromatography triple-quadrupole mass spectrometry (LC–MS/MS). The sample was extracted with methanol containing 1% acetic acid and purified by dispersive solid-phase extraction (d-SPE) with C18. Good linearity (r2 ≥ 0.98) was observed, and the LOQ values ranged from 10 to 200 µg/kg. Average recoveries ranged from 70.8 to 118.4%, and the relative standard deviation was ≤ 18.7%. This validated method was used in the determination of 30 veterinary drugs in 142 feed samples obtained from South Korea. The results show that lincomycin was present in only one of the tested feed samples, although it was detected at a value lower than the LOQ. In conclusion, this multi-residue method can be used for screening through the detection and quantitation of residual multiclass veterinary drugs in feed samples. 相似文献
40.
为了提高设备中电子元件抵御来自外界和内部其他元件的电磁干扰,根据传输线理论,将双层加载电路板屏蔽腔体模型转换为电路图,利用电路图推导出腔体中心屏蔽效能的等效公式。利用Matlab生成传输线法屏蔽效能曲线,并通过仿真软件CST建模仿真,仿真结果与Matlab输出曲线良好吻合,验证了公式的正确性。运用CST研究了一些因素如电路板大小、数量、放置方式以及距孔缝的距离对屏蔽效能的影响。为了更加贴合实际,采用加载集成运算放大电路的印制电路板来研究腔体屏蔽效能以及腔体对电路板功能的影响,最后提出了一些提高屏蔽效能的方法。 相似文献