检索结果-内蒙古大学图书馆

arXiv 2024年

作者： Li, Yitian Tian, Jidong He, Hao Jin, Yaohui MoE Key Lab of Artificial Intelligence AI Institute Shanghai Jiao Tong University China State Key Lab of Advanced Optical Communication System and Network Shanghai Jiao Tong University China

Prompt-based methods have gained increasing attention on NLP and shown validity on many downstream tasks. Many works have focused on mining these methods' potential for knowledge extraction, but few explore their ability to make logical reasoning. In this work, we focus on the effectiveness of the prompt-based methods on first-order logical reasoning and find that the bottleneck lies in logical negation. Based on our analysis, logical negation tends to result in spurious correlations to negative answers, while propositions without logical negation correlate to positive answers. To solve the problem, we propose a simple but effective method, Negation Augmenting and Negation Debiasing (NAND), which introduces negative propositions to prompt-based methods without updating parameters. Specifically, these negative propositions can counteract spurious correlations by providing "not" for all instances so that models cannot make decisions only by whether expressions contain a logical negation. Experiments on three datasets show that NAND not only solves the problem of calibrating logical negation but also significantly enhances prompt-based methods of logical reasoning without model retraining. Copyright © 2024, The Authors. All rights reserved.

关键词： Formal logic

来源：评论

学校读者我要写书评

暂无评论

Low-modal-crosstalk doped-fiber amplifiers in few-mode-fiber-based systems

引用

Photonics Research 2024年第8期12卷 1768-1775页

作者： SHUAILUO HUANG LEI SHEN GANG QIAO YUANPENG DING YUYANG GAO JIAN CUI BAOLONG ZHU SIYUAN LIU MINGQING ZUO JINGLONG ZHU LEI ZHANG JIE LUO YONGQI HE ZHANGYUAN CHEN JUHAO LI State Key Laboratory of Advanced Optical Communication Systems and Networks Peking UniversityBeijing 100871China State Key Laboratory of Optical Fiber and Cable Manufacture Technology Yangtze Optical Fibre and Cable Joint Stock Limited CompanyWuhan 430073China School of Computer and Communication Engineering University of Science and Technology BeijingBeijing 100083China Department of Networks China Mobile Communications Group Co.Ltd.Beijing 100033China Department of Fundamental Network Technology China Mobile Research InstituteBeijing 100053China Pengcheng Laboratory Shenzhen 518055China

Independent light propagation through one or multiple modes is commonly considered as a basic demand for mode manipulation in few-mode fiber(FMF)-or multimode fiber(MMF)-based optical systems such as transmission links,optical fiber lasers,or distributed optical fiber ***,the insertion of doped-fiber amplifiers always kills the entire effort by inducing significant modal *** this paper,we propose the design of doped-fiber amplifiers in FMF-based systems adopting identical multiple-ring-core(MRC)index profiles for both passive and doped fibers to achieve low modal *** develop the direct-glass-transition(DGT)modified chemical vapor deposition(MCVD)processing for precise fabrication of few-mode erbium-doped fibers(FM-EDFs)with MRC profiles of both refractive index and erbium-ion doping ***,a few-mode erbium-doped-fiber amplifier(FM-EDFA)with a maximum gain of 26.08 dB and differential modal gain(DMG)of 2.3 dB is realized based on fabricated FM-EDF matched with a transmission FMF supporting four linearly polarized(LP)*** the insertion of the FM-EDFA,60+60 km simultaneous LP_(01)∕LP_(11)∕LP_(21)∕LP_(02)transmission without inter-modal multiple-input multiple-output digital signal processing(MIMO-DSP)is successfully *** proposed design of low-modal-crosstalk doped-fiber amplifiers provides,to our knowledge,new insights into mode manipulation methods in various applications.

关键词： fiber crosstalk amplifiers

来源：评论

学校读者我要写书评

暂无评论

A Low-CD Weakly-coupled FMF for Short-reach IM/DD MDM Transmission 49

A Low-CD Weakly-coupled FMF for Short-reach IM/DD MDM Transm...

引用

49th European Conference on optical communications, ECOC 2023

作者： Cheng, Ruiting He, Qichen Zuo, Mingqing Zhang, Jiarui Peng, Chuyu Gao, Yuyang Chen, Zhangyuan He, Yongqi Li, Juhao State Key Laboratory of Advanced Optical Communication Systems and Networks Peking University Beijing100871 China Peng Cheng Laboratory Shenzhen518055 China Department of Fundamental Network Technology China Mobile Research Institute Beijing100053 China Fiberhome Fujikura Optic Technology Co. Ltd China

ISBN: (纸本)9781839539954

Based on an accurate model for the relationship between refractive indices and wavelengths in germanium-doped fibers, a weakly-coupled low-chromatic dispersion (CD) FMF is designed and fabricated with CD values lying between-6 and +6 ps/km/nm ranging from 1280 to 1340 nm for all 4 modes. © The Institution of Engineering & Technology 2023.

关键词： Chromatic dispersion

来源：评论

学校读者我要写书评

暂无评论

Butler Matrix Enabled Multi-Beam optical Phased Array for Two-Dimensional Beam-Steering 27

Butler Matrix Enabled Multi-Beam Optical Phased Array for Tw...

引用

27th OptoElectronics and communications Conference/International Conference on Photonics in Switching and Computing, OECC/PSC 2022

作者： Zhou, Zuoyu Xu, Weihan Li, Xinhang Lu, Liangjun Chen, Jianping Zhou, Linjie Shanghai Institute for Advanced Communication and Data Science State Key Laboratory of Advanced Optical Communication Systems and Networks Shanghai Jiao Tong University Shanghai Key Lab of Navigation and Location Services Department of Electronic Engineering Shanghai200240 China SJTU-Pinghu Institute of Intelligent Optoelectronics Pinghu314200 China

We demonstrate a multi-beam optical phased array based on a 4×4 Butler matrix. The device shows the capability of two-dimensional multi-beam steering with a pm 30^{circ}×8^{circ} field-of-view through a shar... 详细信息

ISBN: (数字)9784885523366

ISBN: (纸本)9784885523366

关键词： Beamforming

来源：评论

学校读者我要写书评

暂无评论

A Proposal for On-Chip Isolator Based on Nonreciprocity of Parity-Time Symmetric Directional Coupler

A Proposal for On-Chip Isolator Based on Nonreciprocity of P...

引用

OptoElectronics and communications Conference, OECC

作者： Zijian Pu Hongwei Wang Yu He Yikai Su Department of Electronic Engineering State Key Lab of Advanced Optical Communication Systems and Networks Shanghai Jiao Tong University Shanghai China

Non-Hermitian system has attracted extensive attention, which possesses real eigenvalues if the Hamiltonian satisfies the parity-time (PT) symmetry. In this paper, we adopt the concept of PT symmetry to the widely used directional coupler and theoretically analyze its amplitude and phase characteristics. Finally, we propose an on-chip isolator based on the nonreciprocal characteristic of passive PT symmetric directional coupler. Our proposal can avoid the introduction of the gain on chip or magneto-optical materials.

关键词：

来源：评论

学校读者我要写书评

暂无评论

A Hybrid Lithium Tantalite-Silicon Photonics Platform for Electro-Optic Tuning

A Hybrid Lithium Tantalite-Silicon Photonics Platform for El...

引用

OptoElectronics and communications Conference, OECC

作者： Jian Shen Yong Zhang Chenglong Feng Zihan Xu Lei Zhang Yikai Su Department of Electronic Engineering State Key Lab of Advanced Optical Communication Systems and Networks Shanghai Jiao Tong University Shanghai China

High-efficiency and ultralow-power electro-optic tuning devices are key components in photonic integrated circuits. Silicon photonic technology is considered to be promising for large-scale and low-cost integration. However, silicon does not exhibit any Pockels effect, and the electro-optic tuning based on free-carrier dispersion suffers from challenges such as high power consumption, and large optical propagation loss. Here, a new hybrid lithium tantalite-silicon platform is proposed for ultra-low-power electro-optic tuning based on the Pockels effect. Benefitting from the strong Pockels coefficients of lithium tantalite thin film, an EO tunable lithium tantalite-silicon hybrid microring is demonstrated. The quality factor and extinction ratio are 17000 and 10 dB, respectively. The linear bidirectional wavelength tuning efficiency is measured as 12.8 pm/V. The proposed platform extends the toolbox of silicon photonics technology, which pave a way for high-speed modulators and phase shifters in optical communication and optical phased array.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Design of Polarization Splitter Rotator on AlGaAs-on-insulator

Design of Polarization Splitter Rotator on AlGaAs-on-insulat...

引用

OptoElectronics and communications Conference, OECC

作者： Xiangchen Zhang Weiqiang Xie Yikai Su Department of Electronic Engineering State Key Lab of Advanced Optical Communication Systems and Networks Shanghai Jiao Tong University Shanghai China

A polarization splitter rotator (PSR) is a highly promising solution for polarization management in photonic integrated circuits (PICs). This paper proposes a PSR structure design based on AlGaAs-on-insulator (AlGaAsOI) platform. The device is capable of achieving TM 0 TE 0 conversion on AlGaAsOI, as demonstrated by simulation results.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Multi-carrier 1.44-Tb/s Silicon Photonic Coherent Receiver using IQ Imbalance Compensation

Multi-carrier 1.44-Tb/s Silicon Photonic Coherent Receiver u...

引用

OptoElectronics and communications Conference, OECC

作者： Zhen Wang Xingfeng Li Shuo Wang Jian Shen Yong Zhang Yikai Su Department of Electronic Engineering State Key Lab of Advanced Optical Communication Systems and Networks Shanghai Jiao Tong University Shanghai China

We present a polarization-diversity coherent receiver that enables wavelength-multiplexed reception without arrayed waveguide gratings. We compensate in-phase and quadrature imbalance using a MIMO equalizer, enabling a 1.44-Tb/s capacity of wavelength-division-multiplexed and polarization-division-multiplexed 16-ary quadrature-amplitude-modulation signals.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Compact Photonic Crystal Nanobeam Cavity on Si3N4 Loaded LNOI Platform

Compact Photonic Crystal Nanobeam Cavity on Si3N4 Loaded LNO...

引用

OptoElectronics and communications Conference, OECC

作者： Hua Zhong Ruihuan Zhang Yu He Meng Tian Yong Zhang Yikai Su Department of Electronic Engineering State Key Lab of Advanced Optical Communication Systems and Networks Shanghai Jiao Tong University Shanghai China

In this paper, we design and experimentally demonstrate a photonic crystal nanobeam cavity device based on the Si 3 N 4 loaded LNOI platform with a mode volume of 3.06 $\mu \mathrm{m}^{3}$, which is potential in achieving low power devices. The device shows an insertion loss of 0.89 dB, and a 3-dB bandwidth of 0.284 nm.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Phase Noise Compensation Method and Quantization Noise Effect Analysis for Distributed Fiber-Optic Acoustic Sensor

引用

Guangxue Xuebao/Acta Optica Sinica 2025年第9期45卷

作者： Li, Zhengwen Chen, Jiageng Xiao, Zhengyuan Ji, Jiazhen He, Zuyuan State Key Laboratory of Advanced Optical Communication Systems and Network Shanghai Jiao Tong University Shanghai200240 China

Objective Distributed fiber-optic acoustic sensing (DAS) is an effective technique for measuring dynamic strain along the optical fiber, using Rayleigh backscattering (RBS) as the sensing mechanism. DAS offers high spatial resolution, excellent sensitivity, and strong immunity to electromagnetic interference, making it suitable for applications such as traffic monitoring, seismic detection, and pipeline surveillance. However, its performance is significantly affected by the phase noise of the light source and the quantization noise introduced by the data acquisition system. In this paper, we propose a novel phase noise compensation method tailored for coherent detection and matched filtering-based φ-OTDR systems. We also investigate the influence of quantization noise on strain resolution, aiming to enhance performance while reducing hardware cost. Methods In this paper, we introduce a phase noise compensation method into a conventional φ-OTDR system based on coherent detection and matched filtering to enhance its performance. An auxiliary interferometer is employed to reconstruct the real-time phase of the light source. This reconstructed phase is then applied to compensate for phase noise in both the received signal and the matched filter kernel, thus improving the accuracy of pulse compression and the system’s strain measurement capabilities. A communication-grade semiconductor laser with a 100 kHz linewidth is used in the experimental setup. The strain and spatial resolutions are evaluated over an 84 km single-mode optical fiber, both with and without phase noise compensation. To assess the influence of quantization noise, the analog-to-digital (ADC) bit depth of the data acquisition system is varied from 16 bit down to 2 bit. Results and Discussions With phase noise compensation, the system achieves a strain resolution of 51 pΕ Hz and a spatial resolution of 6.5 m at the end of an 84 km single-mode fiber using a 100 kHz linewidth laser. These results confirm th

关键词： Quantization (signal)

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：