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A NOVEL OTDOA POSITIONING SCHEME IN HETEROGENEOUS LTE-ADVANCED SYSTEMS

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A NOVEL OTDOA POSITIONING SCHEME IN HETEROGENEOUS LTE-ADVANC...

Ce-and La-doped polymetallic layered double hydroxides for enhanced oxygen evolution reaction performance at high current density

2012 3rd IEEE International conference on Network Infrastructure and Digital content

作者： Tao Zhang 1 Dengkun Xiao 2 Jie Cui 2 Xinlong Luo 1 1 School of Information and communication Engineering Beijing University of Posts and Telecommunications Beijing 100876 China 2 Wireless Research Department Beijing Institute huawei technologies co. Ltd Beijing 100094 China

The Observed Time Difference of Arrival （OTDOA） as a major positioning method in 3rd Generation Partnership Project （3GPP） specification has been deeply researched in Long Term Evolution Advanced （LTE-A） system. This paper analyzes the new interference scenarios in Heterogeneous Network （Het-Net） and the drawbacks of conventional OTDOA method which are caused by LPN （Low Power Nodes） deployed in Het-Net. In this paper, we propose a Time division multiplex （TDM） and a code division multiplex （CDM） scheme for positioning reference signal （PRS） transmitting to solve these problems in Het-Net. Simulation results show that the proposed scheme can greatly improve the positioning accuracy compared with the conventional method and its performance meets the Federal communication commission （FCC） requirement.

关键词： CDM Het-Net OTDOA PRS TDM

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Science China Chemistry 2024年第8期67卷 2586-2598页

作者： Rinel R.Kimaka P. Ping Wang Miao He Senyao Meng Jiasai Yao huawei Li Cheng Yang Zhenxing Li State Key Laboratory of Heavy Oil Processing College of New Energy and MaterialsChina University of Petroleum(Beijing)Beijing 102249China

Polymetallic layered double hydroxides are promising cost-effective catalysts for the oxygen evolution reaction(OER) due to their versatile anionic and cationic tunability. Nevertheless, several challenges persist, notably, issues related to low electrical conductivity, poor catalytic activity, and stability, especially at high current density. Herein, we report the design of Ce-and Ladoped co Ni Fe-layered double hydroxide(Ce La co Ni Fe-LDH) nanosheets through a facile and scalable in situ self-assembly strategy that displays enhanced OER activity. Experimental and theoretical investigations provide insights into the impact of Ceand La-doping by comparing Ce co Ni Fe-LDH, La co Ni Fe-LDH, and pristine co Ni Fe-LDH, all synthesized using the same methodology. These results reveal that doping Ce^(3+)and La^(3+)into co Ni Fe-LDH substantially improves its electronic structure,resulting in enhanced conductivity, more oxygen vacancies(Vo), electron interaction, and active site formation. consequently,significantly reduced overpotentials of 175, 314, and 424 m V at 10, 100, and 500 m A cm^(-2), respectively, and a highly stable current density of 120 h in 1 M KOH were achieved. Notably, these performance metrics surpass those of unmodified LDHs and are competitive with many lanthanide-doped transition metal-based LDH electrocatalysts, as well as noble metal catalysts like ruthenium catalysts. This work represents a pioneering effort in doping Ce^(3+)and La^(3+)ions into a functional co Ni Fe-based electrocatalyst, offering inspiring OER performance and scalability potential.

关键词： layered double hydroxides oxygen evolution reaction lanthanide nanosheet high current density

MoO_(x) nanoclusters on Mo-doped TiO_(2) nanosheets with enhanced singlet oxygen generation and sulfide conversion abilities for photocatalytic aerobic oxidative desulfurization

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Science China Chemistry 2024年第1期67卷 408-414页

作者： Suting Xie Xinyu Zhao Dongxiao Wang huawei Yang Lixia Yang Liangjiu Bai Donglei Wei Wenxiang Wang Ying Liang Hou Chen Shaojun Guo college of Chemistry and Materials Science Ludong UniversityYantai 264025China college of Materials Science and Engineering Peking UniversityBeijing 100871China

Photocatalytic aerobic oxidation desulfurization(PAODS)is a promising and sustainable alternative to conventional,energyintensive desulfurization techniques for petroleum ***,its development is greatly plagued by the low capability in generating highly reactive oxygen species and sluggish kinetics of sulfide oxidation of reported *** we report a class of MoO_(x)nanocluster decorated on ultrathin Mo-doped TiO_(2)nanosheet(MoO_(x)/MoTiO)catalyst for efficiently facilitating the photocatalytic aerobic oxidation of *** demonstrate that MoO_(x)/MoTiO can not only promote the generation of highly reactive singlet oxygen(^(1)O_(2))but also enhance the aerobic conversion of sulfides,which leads to a record dibenzothiophene oxidation activity of 3.90 mmol g^(-1)h^(-1).The multiple experimental characterizations and density functional theory calculations collectively reveal that the doped-Mo sites can interact with the photogenerated excitons,enabling directly energy transfer generation of^(1)O_(2)through a new exciton modulation mechanism,and the coordination unsaturated MoO_(x)clusters play the role of co-catalyst to enhance the separation of charge carriers,and effectively catalyze the reaction between sulfides and1O_(2)to form sulfones.

关键词： titanium dioxide photocatalytic aerobic oxidation desulfurization dibenzothiophene singlet oxygen

Layer-by-layer epitaxy growth of thickness-controllable two-dimensional tungsten disulfide

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Science China(Information Sciences) 2024年第5期67卷 302-310页

作者： Jieyuan LIANG Zixing ZOU Junwu LIANG Di WANG Biao WANG Anshi CHU Jiali YI Cheng ZHANG Lizhen FANG Tian ZHANG huawei LIU Xiaoli ZHU Dong LI Anlian PAN Key Laboratory for Micro-Nano Physics and Technology of Hunan Province State Key Laboratory of Chemo/Biosensing and Chemometrics Hunan Institute of Optoelectronic IntegrationCollege of Materials Science and Engineering School of Physics and ElectronicsHunan University School of Electronic Information and Electrical Engineering Changsha University School of Physics and Telecommunication Engineering Yulin Normal University Units Semiconductor Technology co. Ltd. School of Physics and Electronics Hunan Normal University

Bilayer transition metal dichalcogenides（TMDs） balance the high mobility of single layers with the high state density of multilayers and therefore have promising application prospects in high-performance electronics. However, the layer-controlled growth of 2D materials is still confronted with challenges such as poor repeatability between different labs and a limited understanding of the growth mechanism at the atomic scale. Herein, we report a new carbon-assisted chemical vapor deposition process that can realize the growth of WS2sheets with high yield, precise thickness controllability, and repeatability. We show that carbon can act as a reducing agent and catalyst that preferentially reacts with the WO3precursor to form intermediate WO3-xproducts with low-valence state W. The resulting oxycarbide gas has a low surface adsorption energy when deposited on the surface of as-grown WS2, which provides nucleation sites for the subsequent layer of WS2growth and leads to the vertical growth of WS2sheets. The growth mechanism is thoroughly investigated. Electrical transport measurements show that the produced bilayer WS2possesses a high carrier mobility(up to 58 cm2·V-1·s-1) and small subthreshold swing（estimated to be 148 mV/decade）,which are among the best reported results for TMDs produced using CVD.

关键词： WS2 thickness-controlled growth chemical vapor deposition additive carbon

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S3G标准的演进

世界电信 2005年第7期18卷 55-55页

作者： contributed by Wireless Standard Patent Dept. huawei technologies co. Ltd. 华为技术有限公司无线标准专利部

由于IP数据业务的快速增长,3G移动网所使用的分组交换技术需要增强.为保持在性能和成本方面的竞争力,则需要系统级的连续演进和优化.这种长期演进的主要目标包括减少系统时延、提高用户数据率、提高系统容量和覆盖、降低成本.ITU将100 M... 详细信息

由于IP数据业务的快速增长,3G移动网所使用的分组交换技术需要增强.为保持在性能和成本方面的竞争力,则需要系统级的连续演进和优化.这种长期演进的主要目标包括减少系统时延、提高用户数据率、提高系统容量和覆盖、降低成本.ITU将100 Mbit/s速率以下的技术称为增强型3G技术(Enhanced3G).国际标准组织3GPP将这种技术叫做Super 3G,简称为S3G.S3G在演进上可以分成三大块内容:物理层演进;核心网部分演进;接入网部分演进.下面就结合华为公司的理解,介绍S3G标准的演进和展望.

关键词：移动通信网络标准数据业务 S3G标准网络演进

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融合共点声强特征的掩蔽加权声源定位方法

声学学报 2024年第06期49卷 1242-1254页

作者：史文旭陈华伟南京航空航天大学电子信息工程学院

提出了一种适用于小尺寸传声器阵列的掩蔽加权深度学习声源定位方法。该方法在功率谱特征提取的基础上,通过解决声强特征提取中的非共点问题,进一步融合了不同方向上的共点声强特征,有效提高了混响噪声环境条件下的时频掩蔽准确性和定... 详细信息

提出了一种适用于小尺寸传声器阵列的掩蔽加权深度学习声源定位方法。该方法在功率谱特征提取的基础上,通过解决声强特征提取中的非共点问题,进一步融合了不同方向上的共点声强特征,有效提高了混响噪声环境条件下的时频掩蔽准确性和定位性能。该方法无需峰值搜索,计算复杂度较小。仿真和实测实验结果表明,所提方法在混响噪声环境下的定位性能优于现有的掩蔽加权定位方法,且在信噪比较低、混响时间较长条件下优势更为明显,实测实验的声源定位精度超过现有方法 6.67%～10.00%。

关键词：声源定位传声器阵列共点声强特征深度学习时频掩蔽

WCDMA下行链路AWGN功率估计算法的改进

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通信技术 2009年第12期42卷 191-193页

作者：杨燕葛万成吴更石彭念杨靖同济大学上海200092 华为公司上海研究所上海200127

均衡器的一个重要参数是AWGN信道的噪声功率,它的准确度会影响均衡器的性能。提出了一种改进的AWGN噪声功率估计方法,该算法利用信道估计模块得到的信道响应信息,从接收的总噪声中减去符号间干扰功率和多用户之间的信号干扰功率,从而准... 详细信息

均衡器的一个重要参数是AWGN信道的噪声功率,它的准确度会影响均衡器的性能。提出了一种改进的AWGN噪声功率估计方法,该算法利用信道估计模块得到的信道响应信息,从接收的总噪声中减去符号间干扰功率和多用户之间的信号干扰功率,从而准确估计AWGN信道的噪声功率。仿真结果表明,提出的方法能显著提高线性最小均方误差(LMMSE)均衡器的性能,在误码块率(BLER)为8%时,性能约有1dB的改善。

关键词：最小线性均方误差均衡器干扰功率噪声功率估计

基于80C196KC单片机的空调风机温控型专用变频器

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山东大学学报(工学版) 2003年第1期33卷 63-68页

作者：王建民李永斌朱倩影山东大学电气工程学院华为技术有限公司北京研究所 250061.山东省济南市 100085.北京市

介绍了所研制的用于中央空调风机变频调速的温控型专用变频器 ,该变频器采用80C1 96KC单片机 ,功能设置、操作使用方法等针对空调风机进行了专门化设计给出了其软、硬件设计 ,并着重讨论了 80C1 96KC单片机的电压空间矢量PWM实现方法

关键词：变频器温度控制脉宽调制/电压空间矢量调制

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网络暴力治理:平台责任与守门人角色

交大法学 2024年第3期 51-64页

作者：王华伟北京大学法学院

网络暴力不仅侵害个人法益,而且破坏健康的网络生态。网络暴力概念的失焦,群体聚合作用下个体责任的模糊,表达自由与网络监管的平衡需要,使得网络暴力的治理面临诸多困难。在网络暴力多元共治的基本前提下,除了个体责任的认定之外,应当... 详细信息

网络暴力不仅侵害个人法益,而且破坏健康的网络生态。网络暴力概念的失焦,群体聚合作用下个体责任的模糊,表达自由与网络监管的平衡需要,使得网络暴力的治理面临诸多困难。在网络暴力多元共治的基本前提下,除了个体责任的认定之外,应当重视对网络平台的法律规制。不论是从网络技术和传播学的原理还是从法律责任认定的角度,这都是合理的选择。在当下网络空间违法信息与内容的治理中,突出大型网络平台的守门人角色,已经成为国外代表性法案的做法,这也是我国网络暴力规制的重要制度设计方案。网络平台守门人角色的法理内涵,可以从技术措施和义务承担两个角度来具体展开。网络平台守门人制度应当符合我国网络监管模式的国情,重视民法、行政法、刑法等不同部门法的不同规范目标追求,为其合理构建层级性差异,并通过明确可操作的具体规定来落实。

关键词：网络暴力平台责任守门人层级构造