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基于先验梅尔谱和神经声码器的语音丢包隐藏方法

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电子学报 2024年第8期52卷 2581-2590页

作者：黄晋维鲍长春周静北京工业大学信息学部语音与音频信息处理研究所

对基于神经网络的丢包隐藏方法而言，输入特征是直接影响最终恢复效果的重要因素.此外，如何通过丢包隐藏恢复高自然度的语音，也是亟待解决的难题.为有效恢复丢包语音并提高自然度，本文提出了一种基于先验梅尔谱和神经声码器的语音丢... 详细信息

对基于神经网络的丢包隐藏方法而言，输入特征是直接影响最终恢复效果的重要因素.此外，如何通过丢包隐藏恢复高自然度的语音，也是亟待解决的难题.为有效恢复丢包语音并提高自然度，本文提出了一种基于先验梅尔谱和神经声码器的语音丢包隐藏方法 .该方法采用一种非对称的编解码网络结构.在编码端，用两个独立的编码网络分别从时域波形和梅尔谱中提取深层时频特征.在解码端，将时频深层特征一同送入由时序自适应反归一化层构成的声码器中，以恢复丢失的语音信号并提高自然度.仿真实验表明，该方法在语音感知质量和短时客观可懂度上均优于现有的两种丢包隐藏算法.

关键词：丢包隐藏先验梅尔谱神经声码器时序自适应反归一化层时频特征

The FAST all sky HI survey(FASHI):The first release of catalog

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Science China(Physics,Mechanics & Astronomy) 2024年第1期67卷 112-133页

作者： Chuan-Peng Zhang Ming Zhu Peng Jiang Cheng Cheng Jing Wang Jie Wang Jin-Long Xu Xiao-Lan Liu Nai-Ping Yu Lei Qian Haiyang Yu Mei Ai Yingjie Jing Chen Xu Ziming Liu Xin Guan chun Sun Qingliang Yang Menglin huang Qiaoli Hao FAST Collaboration Guizhou Radio Astronomical Observatory Guizhou UniversityGuiyang 550000China National Astronomical Observatories Chinese Academy of Sciences(CAS)Beijing 100101China Chinese Academy of Sciences South America Center for Astronomy National Astronomical ObservatoriesCASBeijing 100101China Kavli Institute for Astronomy and Astrophysics Peking UniversityBeijing 100871China

The FAST All Sky HI survey(FASHI)was designed to cover the entire sky observable by the Five-hundred-meter Aperture Spherical radio Telescope(FAST),spanning approximately 22000 square degrees of declination between-14°and+66°,and in the frequency range of 1050-1450 MHz,with the expectation of eventually detecting more than 100000 HI *** August 2020 and June 2023,FASHI had covered more than 7600 square degrees,which is approximately 35%of the total sky observable by *** has a median detection sensitivity of around 0.76 m Jy beam-1and a spectral line velocity resolution of~6.4 km s-1at a frequency of~1.4 *** of now,a total of 41741 extragalactic HI sources have been detected in the frequency range 1305.5-1419.5 MHz,corresponding to a redshift limit of z■*** cross-matching FASHI sources with the Siena Galaxy Atlas(SGA)and the Sloan Digital Sky Survey(SDSS)catalogs,we found that 16972(40.7%)sources have spectroscopic redshifts and 10975(26.3%)sources have only photometric *** of the remaining 13794(33.0%)HI sources are located in the direction of the Galactic plane,making their optical counterparts difficult to identify due to high extinction or high contamination of Galactic stellar *** on current survey results,the FASHI survey is an unprecedented blind extragalactic H I *** has higher spectral and spatial resolution and broader coverage than the Arecibo Legacy Fast ALFA Survey(ALFALFA).When completed,FASHI will provide the largest extragalactic HI catalog and an objective view of HI content and large-scale structure in the local universe.

关键词： surveys redshifts galaxies telescope radio lines HI line

紫云英压青结合稻秸还田对水稻的节肥增效作用

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植物营养与肥料学报 2024年第2期30卷 279-288页

作者：刘彩玲何春梅王飞黄春应福建省农业科学院资源环境与土壤肥料研究所福建福州350013 三明市农田建设与土肥技术推广站福建三明365000

【目的】紫云英压青结合稻秸还田是降低化肥用量、提高肥料利用率的绿色有效措施。在福建灰(黄)泥田多地开展田间试验,以验证该措施的有效性。【方法】田间试验分别在福建沙县、顺昌县、浦城县进行,沙县供试水稻为头茬再生稻,顺昌和浦... 详细信息

【目的】紫云英压青结合稻秸还田是降低化肥用量、提高肥料利用率的绿色有效措施。在福建灰(黄)泥田多地开展田间试验,以验证该措施的有效性。【方法】田间试验分别在福建沙县、顺昌县、浦城县进行,沙县供试水稻为头茬再生稻,顺昌和浦城为单季稻。所有试验均设置5个处理:不施肥(CK)、100%常规化肥(100%CF)、80%常规化肥(80%CF)、种植翻压紫云英+80%常规化肥(CMV+80%CF)、稻秸还田+种植翻压紫云英+80%常规化肥(RS+CMV+80%CF)。在水稻成熟期,调查产量和产量经济性状,分析氮磷钾养分积累量,并计算水稻产量的变异系数和可持续指数。【结果】与100%CF处理相比,CMV+80%CF和RS+CMV+80%CF处理三地稻谷平均产量和稻秸平均产量增加不显著,但在沙县稻秸产量显著增加33.7%和26.1%。100%CF处理对产量的贡献率较80%CF处理增加了2.74个百分点;CMV+80%CF、RS+CMV+80%CF处理对水稻产量的贡献率较80%CF处理分别提高了7.73%、11.30%,三地RS+CMV+80%CF处理稻谷平均产量比CMV+80%CF处理提高3.9%。各处理间水稻产量变异系数表现为RS+CMV+80%CFCMV+80%CF>100%CF>80%CF,翻压紫云英、紫云英与稻秸联合还田均有利于水稻持续性高产稳产,且紫云英与稻秸联合还田的效果明显高于紫云英单独翻压。翻压紫云英、紫云英与稻秸联合还田均有利于水稻氮、磷、钾养分的累积,与100%CF处理相比,CMV+80%CF处理的平均氮、磷、钾养分回收率分别增加了19.1、20.1、29.5个百分点,RS+CMV+CMV+80%CF处理分别增加了19.3、8.8、30.6个百分点,RS+CMV+80%CF处理的氮、钾养分回收率高于CMV+80%CF处理。RS+CMV+80%CF处理的氮肥农学利用率和氮肥偏生产力最大,较100%CF处理分别增加了76.38%和8.99%。【结论】无论再生稻还是单季稻,在减施化肥用量20%的条件下,紫云英压青结合稻秸还田有利于水稻稳产和产量的可持续性,同时提高养分回收率,增强节肥增效作用,可作为灰黄泥田水稻绿色高效生产的管理制度。

关键词：紫云英稻秸联合还田产量养分利用率

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基于漏斗策略的航天器高精度姿态控制器设计

控制与决策 2024年第5期39卷 1543-1549页

作者：黄元魏春岭严晗郝仁剑北京控制工程研究所空间智能控制技术国家重点实验室北京100190

针对一类具有外部扰动的航天器控制系统,提出一种基于漏斗策略的高精度姿态控制方法,从而对整个跟踪控制轨迹进行规划,保证控制误差时刻满足设计需求,有效提升控制系统动态性能与品质.首先,对所提出姿态控制策略的跟踪性能进行理论分析... 详细信息

针对一类具有外部扰动的航天器控制系统,提出一种基于漏斗策略的高精度姿态控制方法,从而对整个跟踪控制轨迹进行规划,保证控制误差时刻满足设计需求,有效提升控制系统动态性能与品质.首先,对所提出姿态控制策略的跟踪性能进行理论分析,结果表明如果姿态控制误差初值位于根据性能需求设计的漏斗区域内,则在后续任意时刻跟踪误差将始终位于该动态性能漏斗中.在此基础上,考虑到实际工程应用中航天器系统控制信号的有界性需求,给出性能漏斗的优化设计方法,从而保证在输入幅值约束下控制系统的动态性能.最后通过数值仿真验证了所提出航天器姿态漏斗控制策略设计方法及理论分析结果的正确性和有效性.

关键词：航天器姿态跟踪控制漏斗控制策略预设误差性能输入幅值约束扩张状态观测器扰动抑制

Risk factors for renal outcomes in children with antineutrophil cytoplasmic antibody-associated vasculitis:a nationwide retrospective study in China

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World Journal of Pediatrics 2024年第5期20卷 506-516页

作者： Li-Wen Tan Jun-Li Wan chun-Hua Zhu Hong Xu Zheng-Kun Xia Li-Zhi Chen Xiao-Chuan Wu Fang Wang Xiao-Rong Liu Cheng-Guang Zhao Xiao-Zhong Li Jian-Hua Mao Xiao-Wen Wang Wen-Yan huang Yu-Hong Li Jian-Jiang Zhang Shi-Pin Feng Jun Yang Jiao-Jiao Liu chun-Lin Gao Li-Ping Rong Lan-Jun Shuai Ke Xu He-Jia Zhang Qiu Li Ai-Hua Zhang Mo Wang Department of Nephrology Children’s Hospital of Chongqing Medical UniversityZhongshan 2nd Rd.136Chongqing400014China Ministry of Education Key Laboratory of Child Development and Disorders National Clinical Research Center for Child Health and DisordersChina International Science and Technology Cooperation Base of Child Development and Critical DisordersChildren’s Hospital of Chongqing Medical UniversityChongqingChina Chongqing Key Laboratory of Pediatrics Children’s Hospital of Chongqing Medical UniversityChongqingChina Department of Nephrology Children’s Hospital of Nanjing Medical University72 Guangzhou RoadNanjing210008China Department of Nephrology Children’s Hospital of Fudan UniversityNational Paediatric Medical Center of ChinaShanghaiChina Department of Pediatrics Jinling HospitalNanjing Medical UniversityNanjingChina Department of Pediatrics Jinling HospitalThe First School of Clinical MedicineSouthern Medical UniversityNanjingChina Department of Pediatrics Jinling HospitalMedical School of Nanjing UniversityNanjingChina Department of Pediatric Nephrology and Rheumatology The First Affiliated Hospital of Sun Yat-Sen UniversityGuangzhouChina Department of Pediatrics The Second Xiangya Hospital of Central South UniversityChangshaChina Department of Pediatrics Peking University First HospitalBeijingChina Department of Nephrology Beijing Children’s HospitalCapital Medical UniversityBeijing100045China National Center for Children’s Health BeijingChina Department of Pediatrics Shengjing Hospital of China Medical UniversityShenyangChina Department of Nephrology and Immunology Children’s Hospital of Soochow UniversitySuzhouChina Department of Nephrology Children HospitalZhejiang University School of MedicineHangzhouChina Department of Nephrology Wuhan Children’s Hospital(Wuhan Maternal and Child Healthcare Hospital)Tongji Medical CollegeHuazhong University of Science&TechnologyWuhanChina Department of Nephrology and Rheumatology Shanghai Children’s HospitalSchool

Background Pediatric antineutrophil cytoplasmic antibody-associated vasculitis(AAV)is a life-threatening systemic vasculitis featured by liability to renal ***,there are few studies on the risk factors and predictive models for renal outcomes of AAV in *** Data from 179 AAV children in multiple centers between January 2012 and March 2020 were collected *** risk factors and predictive model of end-stage renal disease(ESRD)in AAV were *** Renal involvement was the most typical manifestation(95.5%),and the crescent was the predominant pathological lesion(84.9%).The estimated glomerular filtration rate(eGFR)was evaluated in 114 patients,of whom 59.6%developed ESRD,and the median time to ESRD was 3.20 *** eGFR[P=0.006,odds ratio(OR)=0.955,95%confidence interval(CI)=0.924–0.987]and the percentages of global glomerulosclerosis(pGGS;P=0.018,OR=1.060,95%CI=1.010–1.112)were independent risk factors for ESRD of renal *** on the pGGS and eGFR at renal biopsy,we developed three risk grades of ESRD and one predictive *** Kaplan‒Meier curve indicated that renal outcomes were significantly different in different risk grades(P<0.001).Compared with serum creatinine at baseline,the predictive model had higher accuracy(0.86 versus 0.58,P<0.001)and a lower coefficient of variation(0.07 versus 0.92)in external *** Renal involvement is the most common manifestation of pediatric AAV in China,of which more than half deteriorates into *** predictive model based on eGFR at renal biopsy and the pGGS may be stable and accurate in speculating the risk of ESRD in AAV children.

关键词： Antineutrophil cytoplasmic antibody End-stage renal disease Glomerulonephritis Pediatric nephrology Vasculitis

A thermodynamic perspective on electrode poisoning in solid oxide fuel cells

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1449-1455页

作者： Kevin huang Department of Mechanical Engineering University of South CarolinaColumbiaUSA

A critical challenge to the commercialization of clean and high-efficiency solid oxide fuel cell(SOFC)technology is the insuf-ficient stack lifespan caused by a variety of degradation mechanisms,which are associated with cell components and chemical *** components related degradation refers to thermal/chemical/electrochemical deterioration of cell materials under operating conditions,whereas the latter regards impurities in feedstocks of oxidant(air)and reductant(fuel).This article provides a thermodynamic perspective on the understanding of the impurities-induced degradation mechanisms in *** discussion focuses on using thermodynamic ana-lysis to elucidate poisoning mechanisms in cathodes by impurity species such as Cr,CO_(2),H_(2)O,and SO_(2) and in the anode by species such as S(or H_(2)S),SiO_(2),and P_(2)(or PH_(3)).The author hopes the presented fundamental insights can provide a theoretical foundation for search-ing for better technical solutions to address the critical degradation challenges.

关键词： impurities air fuel reaction activity

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软坚散结颗粒制备工艺及其质量标准建立

中成药 2024年第4期46卷 1118-1125页

作者：吴玥黄春跃雷春胡晓侯爱君复旦大学药学院上海201203 上海医药工业研究院有限公司创新药物与制药工艺国家重点实验室上海201203 上海交通大学药学院上海200240

目的建立软坚散结颗粒制备工艺及其质量标准。方法优化挥发油包合工艺和颗粒成型工艺,确定颗粒制备工艺。TLC法定性鉴别玄参、浙贝母、莪术、麸炒白术,HPLC法测定哈巴苷、哈巴俄苷、贝母素甲、贝母素乙的含量。结果最佳包合工艺为挥... 详细信息

目的建立软坚散结颗粒制备工艺及其质量标准。方法优化挥发油包合工艺和颗粒成型工艺,确定颗粒制备工艺。TLC法定性鉴别玄参、浙贝母、莪术、麸炒白术,HPLC法测定哈巴苷、哈巴俄苷、贝母素甲、贝母素乙的含量。结果最佳包合工艺为挥发油与β-环糊精比例1∶10,包合时间120 min,包合温度45℃;最优成型工艺为按药辅比1∶0.8混入可溶性淀粉,90%乙醇润湿,制粒。TLC斑点清晰,阴性无干扰。哈巴苷、哈巴俄苷、贝母素甲、贝母素乙在各自范围内线性关系良好(r≥0.999 4),平均加样回收率105.63%~110.87%,RSD 2.9%~5.6%。结论软坚散结颗粒制备工艺稳定可行,并且该制剂质量标准专属性强,重复性好,可用于其质量控制。

关键词：软坚散结颗粒制备工艺质量标准 TLC HPLC

RNA m^(6)A reader YTHDF2 facilitates precursor miR-126 maturation to promote acute myeloid leukemia progression

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Genes & Diseases 2024年第1期11卷 382-396页

作者： Zheng Zhang Keren Zhou Li Han Andrew Small Jianhuang Xue Huilin huang Hengyou Weng Rui Su Brandon Tan Chao Shen Wei Li Zhicong Zhao Ying Qing Xi Qin Kitty Wang Keith Leung Mark Boldin chun-Wei Chen David Ann Zhijian Qian Xiaolan Deng Jianjun Chen Zhenhua Chen Department of Systems Biology Beckman Research Institute of City of HopeMonroviaCA 91016USA Irell and Manella Graduate School of Biological Sciences Beckman Research Institute of City of HopeDuarteCA 91010USA Gehr Family Center for Leukemia Research City of HopeDuarteCA 91010USA Sun Yat-sen University Cancer Center State Key Laboratory of Oncology in South ChinaCollaborative Innovation Center for Cancer MedicineGuangzhouGuangdong 510060China Guangzhou Laboratory GuangzhouGuangdong 510005China Bioland Laboratory GuangzhouGuangdong 51005China Department of Liver Surgery Renji HospitalShanghai Jiao Tong University School of MedicineShanghai 200127China Department of Diabetes Complications and Metabolism Beckman Research Institute of City of HopeDuarteCA 91010USA Department of Biochemistry and Molecular Biology University of FloridaGainesvilleFL 32603USA Tongji Hospital Affiliated to Tongji University Frontier Science Center for Stem Cell ResearchSchool of Life Sciences and TechnologyTongji UniversityShanghai 200092China School of Pharmacy China Medical UniversityShenyangLiaoning 110001China

As the most common internal modification of mRNA,Ne-methyladenosine(m^(6)A)and its regulators modulate gene expression and play critical roles in various biological and patholog-ical processes including *** was reported previously that m^(6)A methyltransferase(writer),methyltransferase-like 3(METTL3)adds m^(6)A in primary microRNAs(pri-miRNAs)and fa-cilitates its processing into precursor miRNAs(pre-miRNAs).However,it is unknown whether m^(6)A modification also plays a role in the maturation process of pre-miRNAs and(if so)whether such a function contributes to ***,we found that YTHDF2 is aberrantly overexpressed in acute myeloid leukemia(AML)patients,especially in relapsed patients,and plays an onco-genic role in ***,YTHDF2 promotes expression of miR-126-3p(also known as miR-126,as it is the main product of precursor miR-126(pre-miR-126)),a miRNA that was reported as an oncomiRNA in AML,through facilitating the processing of pre-miR-126 into mature ***,YTHDF2 recognizes m^(6)A modification in pre-miR-126 and recruits AGO2,a regulator of pre-miRNA processing,to promote the maturation of ***2 posi-tively and negatively correlates with miR-126 and miR-126's downstream target genes,respec-tively,in AML patients,and forced expression of miR-126 could largely rescue YTHDF2/Ythdf2 depletion-mediated suppression on AML cell growth/proliferation and leukemogenesis,indi-cating that miR-126 is a functionally important target of YTHDF2 in ***,our studies not only reveal a previously unappreciated YTHDF2/miR-126 axis in AML and highlight the ther-apeutic potential of targeting this axis for AML treatment,but also suggest that m^(6)A plays a role in pre-miRNA processing that contributes to tumorigenesis.

关键词： AML miR-126 N^(6)-methyladenosine Pre-miRNA maturation YTHDF2

组织学习、环境不确定性对直播电商企业场景化创新的影响——资源拼凑的视角

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企业经济 2024年第1期43卷 14-23页

作者：闫春黄绍升山西财经大学工商管理学院山西太原030006 岭南师范学院社会与公共管理学院广东湛江524048

内外部经验学习广泛存在于直播电商行业,并影响企业的场景化创新。本文基于组织学习视角,通过334家直播电商企业数据,阐释了替代式学习和体验式学习对企业场景化创新的作用机理。研究发现:替代式学习、体验式学习及两者的互补效应正向... 详细信息

内外部经验学习广泛存在于直播电商行业,并影响企业的场景化创新。本文基于组织学习视角,通过334家直播电商企业数据,阐释了替代式学习和体验式学习对企业场景化创新的作用机理。研究发现:替代式学习、体验式学习及两者的互补效应正向影响场景化创新,且互补效应作用效果更大;资源拼凑在替代式学习和体验式学习影响场景化创新路径上具有中介效应;环境不确定性对组织学习与场景化创新的作用具有“双刃剑”调节效应,即正向调节替代式学习与场景化创新的关系,但负向调节体验式学习与场景化创新的关系。因此,直播电商企业应增强组织学习的积极性,重视组织资源的拼凑利用,依托外源性知识把握场景创新机会,以更好应对环境不确定性带来的挑战。

关键词：场景化创新组织学习资源拼凑环境不确定性直播电商