Institution
University of Electro-Communications
Education•Tokyo, Japan•
About: University of Electro-Communications is a education organization based out in Tokyo, Japan. It is known for research contribution in the topics: Laser & Robot. The organization has 8041 authors who have published 16950 publications receiving 235832 citations. The organization is also known as: UEC & Denki-Tsūshin Daigaku.
Topics: Laser, Robot, Fiber laser, Mobile robot, Control theory
Papers published on a yearly basis
Papers
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TL;DR: Tin-lead (Sn-Pb)-based perovskite solar cells (PSCs) still exhibit inferior power conversion efficiency (PCE) compared to their pure Pb counterparts because of high voltage loss (VL) and high photo...
Abstract: Tin–lead (Sn–Pb)-based perovskite solar cells (PSCs) still exhibit inferior power conversion efficiency (PCE) compared to their pure Pb counterparts because of high voltage loss (VL) and high photo...
104 citations
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TL;DR: It is found that aging of SnCl2 precursor solution for electron transporting layer can promote the Voc of CsPbI2Br solar cells employing a dopant-free-polymer HTM over 1.40 V and efficiency over 15.5% with high reproducibility.
Abstract: CsPbI2Br perovskite solar cells have attracted much attention because of the rapid development in their efficiency and their great potential as a top cell of tandem solar cells. However, the VOC outputs observed so far in most cases are far from that desired for a top cell. Up to now, with various kinds of treatments, the reported champion VOC is only 1.32 V, with a VOC deficit of 0.60 V. In this work, we found that aging of the SnCl2 precursor solution for the electron-transporting layer can promote the VOC of CsPbI2Br solar cells by employing a dopant-free-polymer hole transport material (HTM) over 1.40 V and efficiency over 15.5% with high reproducibility. With the champion VOC of 1.43 V, the VOC deficit was reduced to <0.50 V, which is achieved for the first time. This simple technique of SnCl2 solution aging forms a uniform and smooth amorphous SnOx film with pure Sn4+, elevates the conduction band of SnOx, and reduces the interfacial gaps and the trap state density of the device, resulting in enhancement in average VOC from ∼1.2 V in the nonaged case to ∼1.4 V in the aged case. Furthermore, the device using an aged SnCl2 solution also exhibits a much better long-term stability than that made of the fresh solution. These achievements in dopant/additive-free CsPbI2Br solar cells can be useful for future research on CsPbI2Br and tandem solar cells.
104 citations
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TL;DR: A number of Raman active peaks in the low frequency region (100−600 cm−1) were observed for radial breathing modes (RBMs) by using polarized Raman scattering as discussed by the authors.
104 citations
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TL;DR: A new approach on how to teach a robot everyday manipulation tasks under the "Learning from Observation" framework is described, which is examined by using a human-form robot, which successfully imitates human demonstrations of everyday tasks.
Abstract: This paper describes a new approach on how to teach a robot everyday manipulation tasks under the "Learning from Observation" framework. In this approach, human demonstrations, which are made up of mutual interactions between a grasped object and an environmental object, are observed and a reusable manipulation task model is automatically generated. Most of the similar approaches so far assume that a demonstration can be well understood from a single demonstration. However, a single demonstration contains ambiguity, in that interactions which are essential to complete a task cannot be discerned without prior task dependent knowledge, which should be obtained from observation. To address these issues, a technique to integrate multiple observations of demonstrations is proposed. The demonstrations differ, but are virtually the same task. The shared interactions among all the demonstrations are considered to be essential and a task model is generated from their symbolic representations. Then, the relative trajectories corresponding to each essential interaction are generalized by calculating their mean and variance, and they are also stored in the task model, which is used to reproduce skilled behavior. This approach is examined by using a human-form robot, which successfully imitates human demonstrations of everyday tasks.
104 citations
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TL;DR: This work reports the first direct and quantitative experimental measurement of a generic coherence vortex, controlled by controlling the irradiance of an extended quasimonochromatic, spatially incoherent source.
Abstract: By controlling the irradiance of an extended quasimonochromatic, spatially incoherent source, an optical field is generated that exhibits spatial coherence with phase singularities, called coherence vortices. A simple optical geometry for direct visualization of coherence vortices is proposed, and the local properties and the spatial evolution of coherence vortex are experimentally investigated. To our knowledge, this is the first direct and quantitative experimental measurement of a generic coherence vortex.
104 citations
Authors
Showing all 8079 results
Name | H-index | Papers | Citations |
---|---|---|---|
Mildred S. Dresselhaus | 136 | 762 | 112525 |
Matthew Nguyen | 131 | 1291 | 84346 |
Juan Bisquert | 107 | 450 | 46267 |
Dapeng Yu | 94 | 745 | 33613 |
Riichiro Saito | 91 | 502 | 48869 |
Shun-ichi Amari | 90 | 495 | 40383 |
Shigeru Nagase | 76 | 617 | 22099 |
Ingrid Verbauwhede | 72 | 575 | 21110 |
Satoshi Hasegawa | 69 | 708 | 22153 |
Yu Qiao | 69 | 484 | 29922 |
Yukio Tanaka | 68 | 744 | 19942 |
Zhijun Li | 68 | 614 | 14518 |
Iván Mora-Seró | 67 | 235 | 23229 |
Kazuo Tanaka | 63 | 535 | 27559 |
Da Xing | 63 | 624 | 14766 |