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Agglutinative Language Speech Recognition Using Automatic Allophone Deriving

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Chinese Journal of Electronics 2016年第2期25卷 328-333页

作者： XU Ji pan Jielin yan Yonghong The Key Laboratory of Speech Acoustics and Content Understanding Chinese Academy of Sciences

Agglutinative language involves agglutination extensively, which results in the significant pronunciation variations in different contexts. Therefore, it is a problem to use phoneme sets translated from their written forms as basic units for acoustic modeling, due to the incapability to capture the pronunciation variations in Large-vocabulary continuous speech recognition(LVCSR).This paper presented a novel approach called Automatic allophone deriving(AAD) to create allophone candidates without any linguistic prior knowledge. Furthermore, an enhanced approach AAD-LT is proposed in which longtime features are used in AAD approach. Experiments are conducted on three languages which contains two agglutinative ones and an analytic one. The experiments suggest that AAD Long-time(AAD-LT) is very effective for the agglutinative languages in which more than 10% relative CER reduction is obtained.

关键词： Agglutinative language Large-vocabulary continuous speech recognition(LVCSR) Allophone Unsupervised

Microbial biodegradation of microcystin-RR by bacterium Sphingopyxis sp. USTB-05

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Journal of Environmental Sciences 2010年第2期22卷 168-175页

作者： Mulan Zhang Gang pan Hai yan State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China Department of Biological Science and Technology School of Applied Science University of Science and Technology Beijing Bering 100083 China

A strain, USTB-05, isolated from Lake Dianchi, China, degraded the cyanobacterial toxin microcystin-RR （MC-RR） at the rate of 16.7 mg/L per day. Analysis of 16S rDNA sequence showed that the strain was Sphingopyxis sp. Enzymatic degradation pathways for MC-RR by Sphingopyxis sp. USTB-05 were identified. Adda-Arg peptide bond of MC-RR was cleaved and then a hydrogen and a hydroxyl were combined onto the NH2 group of Adda and the carboxyl group of arginine to form a linear molecule as intermediate product within the first few hours. Then, through dehydration reaction, two hydrogen of amino group on arginine reacted with adjacent hydroxyl on carbon to form a linear MC-RR with two small peptide rings as the final product after 24 hr. These biodegradation pathways were different from those reported for other strains, implying that MC-RR may undergo different transformations and different products were formed due to various bacteria in natural lakes and reservoirs.

关键词： microcystin-RR biodegradation Sphingopyxis sp. USTB-05 enzymatic pathways Lake Dianchi

Detoxifying PCDD/Fs and heavy metals in fly ash from medical waste incinerators with a DCdouble arc plasma torch

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Journal of Environmental Sciences 2013年第7期25卷 1362-1367页

作者： Xinchao pan Jianhua yan Zhengmiao Xie Institute of Environmental Science &Technology Hangzhou Dianzi University Institute for Thermal Power Engineering Zhejiang University

Medical waste incinerator （MWI） fly ash is regarded as a highly toxic waste because it contains high concentrations of heavy metals anddioxins, including polychlorinateddibenzo-p-dioxins （PCDDs） and polychlorinateddibenzofurans （PCDFs）. Therefore fly ash from MWI must be appropriately treated before beingdischarged into the environment. A melting process based on adirect current thermal plasma torch has beendeveloped to convert MWI fly ash into harmless slag. The leaching characteristics of heavy metals in fly ash and vitrified slag were investigated using the toxicity characteristic leaching procedure, while the content of PCDD/Fs in the fly ashes and slags was measured using method 1613 of the US EPA. The experimental results show that thedecomposition rate of PCDD/Fs is over 99% in toxic equivalent quantity value and the leaching of heavy metals in the slag significantlydecreases after the plasma melting process. The produced slag has a compact and homogeneous microstructure withdensity of up to2.8 g/cm3 .

关键词： medical waste incinerator fly ash plasma torch PCDD/Fs heavy metal

Evolution and final closure of the Mongol-Okhotsk Ocean

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Science China Earth Sciences 2023年第11期66卷 2497-2513页

作者： pan ZHAO Bei XU yan CHEN State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Hebei Key Laboratory of Strategic Critical Mineral Resources Hebei GEO UniversityShijiazhuang 050031China Universitéd’Orléans CNRSBRGMISTOUMR 7327Orléans F-45071France

Mongol-Okhotsk Orogenic Belt is the last main orogen that constructs modern tectonic framework of northeastern Asia. It has recorded the long-term evolution of the Mongol-Okhotsk Ocean(MOO) from its Early Paleozoic initial opening,through the Late Paleozoic-Early Mesozoic subduction, to its Mesozoic final closure, leading to the amalgamation of the Siberian Craton(SIB) and North China-Amuria Block(NCC-AMB). Opening of the MOO can be traced to the early stage of the Early Paleozoic. Northward subduction of the Mongol-Okhotsk oceanic slab beneath the southern margin of the SIB initiated in the Silurian, whereas the southward subduction beneath the northern margin of the NCC-AMB started in the Late Devonian. The bidirectional subduction of the Mongol-Okhotsk oceanic slab resulted in pulse arc magmatism, with three main peaks in the earliest Carboniferous, Late Permian, and Late Triassic-Early Jurassic. In the Late Triassic, the collision between the AMB and Western Mongolian Blocks led to the bending of the Western Mongolian Blocks, which caused the initial closure of the MOO in its western segment. Due to the clockwise rotation of the SIB and counterclockwise rotation of the NCC-AMB, the MOO showed a scissor-like closure from west to east. The final closure of the MOO occurred in the Middle-Late Jurassic, which also resulted in the formation of the Mongol Orocline. Since then, the amalgamation of blocks in northeastern Asia has finished, and the northeastern Asian continent went into the intraplate evolutional stage.

关键词： Northeastern Asia Mongol-Okhotsk Ocean Paleozoic-Mesozoic Subduction initiation Scissor-like closure

Study on soil heavy metals contamination of a lead refinery

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Chinese Journal Of Geochemistry 2014年第4期33卷 393-397页

作者： shu yan ZHAI Shengjia Environmental Development Centre of Ministry of Environmental Protection Appraisal Center for Environment & Engineering Ministry of Environmental Protection China University of Petroleum

The contents of Pb, Cd, Cr, As, and Hg was investigated in the neighboring areas of a lead smelting enterprise and the metals contamination of soil was evaluated with the methodologies of the single factor index and Nemerow integrated index. It is found that the content of heavy metals in the neighboring areas has no obvious difference from the reference points. And the soil contamination of heavy metals varies by elements, the contamination index follows the pollution order: Cd>Hg>Cr>As>Pb. The pollution degree of Cd is at high level and Hg at low level, but Cr and As reached the warning level. Therefore, the lead smelting enterprises should not only control lead but also other heavy metals as Cd.

关键词：土壤重金属污染精炼厂铅重金属镉冶炼企业综合指数邻近地区污染元素

高光谱预处理方法与多模型在分类判别中的对比研究

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光谱学与光谱分析 2025年第1期45卷 125-132页

作者：居雷于洁吴炎淼李丽卢天丁亚萍束茹欣上海烟草集团有限责任公司技术中心上海200082 上海大学化学系上海200444 上海数之微信息科技有限公司上海200444

高光谱技术能够快速、无损地获取丰富的信息,在植物研究和监测中已成为一种广泛应用的工具。茄科植物作为一种重要的经济农作物,与高光谱技术结合进行研究具有巨大的应用潜力。本研究采用高光谱技术对茄科植物的初烤后不同部位叶片进行... 详细信息

高光谱技术能够快速、无损地获取丰富的信息,在植物研究和监测中已成为一种广泛应用的工具。茄科植物作为一种重要的经济农作物,与高光谱技术结合进行研究具有巨大的应用潜力。本研究采用高光谱技术对茄科植物的初烤后不同部位叶片进行分类研究。采用Field Spec 3光谱辐射仪对293份不同部位的茄科植物粉末样本进行高光谱采样,采用S-G平滑以及一阶导数和二阶导数的方法对数据进行预处理,用于信息增强和去除噪声,并通过偏最小二乘法对数据进行降维,以减少冗余特征。基于降维数据,采样支持向量机、逻辑回归、K近邻、决策树、随机森林和梯度提升决策树这六种机器学习算法建立分类模型。结果显示,在分类任务中,经过一阶导数处理后,支持向量机模型最佳,在训练集和测试集上分别实现了100.0%和84.7%的准确率。经网格参数优化后确定最优参数为:最大深度不限制,最小样本分割数为4,估计器数量为200。参数优化后五折交叉验证准确率为88.1%,训练集准确率为100%,测试集准确率为86.4%。研究结果表明,预处理方法结合降维方法能够增强数据信息使得分类模型能够更好地捕捉茄科植物样本的特征。该研究对于快速、准确、无损地区分茄科植物的部位具有重要意义。

关键词：高光谱部位分类机器学习

Structure and Dynamics of Energy Materials from Machine Learning Simulations:A Topical Review

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Chinese Journal of Chemistry 2021年第11期39卷 3144-3154页

作者： shu-Hui Guan Cheng Shang Zhi-pan Liu Shanghai Academy of Agricultural Sciences Shanghai201403 China Collaborative Innovation Center of Chemistry for Energy Material Shanghai Key Laboratory of molecular Catalysis and Innovative MaterialsKey Laboratory of Computational Physical ScienceDepartment of ChemistryFudan UniversityShanghai200438 China

Energy materials featuring the capability to store and release chemical energy reversibly involve generally complex geometrical structures with multiple *** has been a great challenge to establish the quantitative relationship between the structure of materials and their dynamic physicochemical *** recent years,machine learning(ML)technique has demonstrated its great power in accelerating the research on energy *** topical review introduces the key ingredients and typical applications of ML to energy *** mainly focus on the ML based atomic simulation via ML potentials in different architectures/implementations,including high dimensional neural networks(HDNN),Gaussian approximation potential(GAP),moment tensor potentials(MTP)and stochastic surface walking global optimization with global neural network potential(SSW-NN)*** cases studies,namely,Si,LiC and LiTiO systems,are presented to demonstrate the ability of ML simulation in assessing the thermodynamics and kinetics of complex material *** highlight that the SSW-NN method provides an automated solution for global potential energy surface data collection,ML potential construction and ML simulation,which boosts the current ability for large-scale atomic simulation and thus holds the great promise for fast property evaluation and material discovery.

关键词： Machine learning Materials science Atomic simulation Thermodynamics Kinetics

DISSIPATIVE NUMERICAL METHODS FOR THE HUNTER-SAXTON EQUATION

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Journal of Computational Mathematics 2010年第5期28卷 606-620页

作者： yan Xu Chi-Wang shu Department of Mathematics University of Science and Technology of China Hefei 230026 China Division of Applied Mathematics Brown University Providence RI 02912 USA

In this paper, we present further development of the local discontinuous Galerkin （LDG） method designed in [21] and a new dissipative discontinuous Galerkin （DG） method for the HuntermSaxton equation. The numerical fluxes for the LDG and DG methods in this paper are based on the upwinding principle. The resulting schemes provide additional energy dissipation and better control of numerical oscillations near derivative singularities. Stability and convergence of the schemes are proved theoretically, and numerical simulation results are provided to compare with the scheme in [21].

关键词： Discontinuous Galerkin method Local discontinuous Galerkin method dissi-pation Hunter-Saxton equation Stability.

The regulation of coordination structure between cobalt and nitrogen on graphene for efficient bifunctional electrocatalysis in Zn-air batteries

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Journal of Energy Chemistry 2022年第5期31卷 213-221页

作者： Xinxin shu Maomao yang Miaomiao Liu Wei pan Jintao Zhang Key Laboratory for Colloid and Interface Chemistry of State Education Ministry School of Chemistry and Chemical EngineeringShandong UniversityJinan 250100ShandongChina College of Chemistry Chemical Engineering and Materials ScienceShandong Normal UniversityJinan 250014ShandongChina State Key Laboratory of Crystal Materials Shandong UniversityJinan 250100ShandongChina

Electrocatalysts with atomically dispersed metal moieties are of importance in enhancing electrocatalysis for a specific reaction including oxygen reduction. However, it is still challenging to modulate the coordination structure of metal atoms with heteroatoms on carbon supports. Herein, an innovative and facile bridging strategy to regulate the coordination structure of cobalt with nitrogen atoms on reduced graphene oxide(r GO) sheets was developed by the interfacial complexation of amino-rich folic acid with cobalt ions on graphene oxide sheets and the subsequent thermal treatment. Typically, the actual coordination interaction between cobalt and nitrogen species was revealed by using X-ray absorption spectroscopy(XAS), exhibiting the Co-N_(4) coordination structure well-dispersed on reduced graphene *** unique structure enables the efficient oxygen reduction and evolution reactions via the favorable adsorption and desorption of intermediates. With the enhanced bifunctional electrocatalytic activities,the fabricated Zn-air battery exhibited the excellent performance with large power density of 319.8 mW cm^(-2) and good long-term stability(over 300 h). This work establishes the synthesis strategy for bridging metal atom with heteroatom on graphene sheets to enhance the bifunctional electrocatalysis toward Zn-air batteries.

关键词： Oxygen reduction reaction Synergistic effect Bifunctional electrocatalysis Bridging structure