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Study on Acoustic Modeling in a Mandarin Continuous Speech Recognition

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Journal of China University of Mining and Technology 2007年第1期17卷 143-146页

作者： PENG Di liu Gang guo jun School of Information Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

The design of acoustic models is of vital importance to build a reliable connection between acoustic wave-form and linguistic messages in terms of individual speech units. According to the characteristic of Chinese phonemes, the base acoustic phoneme units set is decided and refined and a decision tree based state tying approach is explored. Since one of the advantages of top-down tying method is flexibility in maintaining a balance between model accuracy and complexity, relevant adjustments are conducted, such as the stopping criterion of decision tree node splitting, during which optimal thresholds are captured. Better results are achieved in improving acoustic modeling accuracy as well as minimizing the scale of the model to a trainable extent.

关键词： acoustic model base acoustic phoneme units decision tree

Lepton-Flavor Violating Processes li → ljγ in Topcolor-Assisted Technicolor Models

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Communications in Theoretical Physics 2002年第10期38卷 461-464页

作者： YUE Chong-Xing XU Qing-jun liu guo-Li CCAST World Laboratory P.O. Box 8730 Beijing 100080 China College of Physics and Information Engineering Henan Normal University Xinxiang 453002 China College of Physics and Information Engineering Henan Normal University Xinxiang 453002 China College of Physics and Information Engineering Henan Normal University Xinxiang 453002 China

We consider the lepton-flavor violating (LFV) processes li → ljγ in the framework of topcolor-assistedtechnicolor (TC2) models. We find that the new gauge boson Z' predicted by TC2 models can give significantlycontributions to these processes via the flavor-changing couplings Z'lilj. The present experimental bound on the LFVprocess μ→ eγ gives severe constraints on the TC2 models. Using other experimental constraints on the Z' mass Mz,we obtain constraints on the lepton mixing factors KTμ and KTe. The future LFV experiments will probe into TC2models.

关键词： lepton flavor, topcolor-assisted technicolor (TC2)

Design and Implementation of a Network Management System Based on Mobile RMON Agent

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Journal of China University of Mining and Technology 2006年第3期16卷 325-329页

作者： SHAN Xin liu Peng WU Lin liu Ying guo jun School of Information Engineering Beijing University of Posts ＆ Telecommunications Beijing 100876 China

To improve the scalability of RMON-based network management, the concept of Mobile RMON Agent (MRA) was presented by combining the mobile agent technology with RMON. Then an MRA-based Network Management System (MRANMS) was designed and implemented. RMON functions were achieved by programming the mobile agent to make it capture and analyze packets locally. The experimental result on the Grasshopper platform indicates that MRA as a mobile agent can migrate to another subnet and calculate a RMON MIB value and TrafficMatrix in a subnet with 29 hosts. Furthermore, the behavior of MRA can be customized to achieve new RMON functions, such as the statistics of hostTable in RMON MIB. It can be concluded that MRANMS is based on the mode of distribution, and besides the compatibility with standard RMON, the system possesses scalability of management function.

关键词： network management RMON mobile agent MRA scalability

Nucleation of Bainite in Bainite Ductile Cast Iron

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Journal of Iron and Steel Research International 2004年第3期11卷 41-43页

作者： ZHAI Qi-jie liu guo-jun ZHAI Hua-ying LI Zu-qi Shanghai University University of Science and Technology Beijing

The bainite ductile cast iron with given composition was quenched to get bainite *** nucleating position of bainite and the distribution of alloying elements in the matrix were *** results show that the bainite nucleates at the interface between graphite and austenite during *** on the experimental results and thermodynamics,the nucleating mechanism of bainite in ductile iron was analyzed.

关键词： bainite ductile cast iron nucleation thermodynamics

“Co-coordination force”assisted rigid-flexible coupling crystalline polymer for high-performance aqueous zinc-organic batteries

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Chinese Chemical Letters 2024年第9期35卷 501-506页

作者： jun guo Zhenbang Zhuang Wanqiang liu Gang Huang School of Materials Science and Engineering Changchun University of Science and TechnologyChangchun 130022China State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Key Laboratory of Automobile Materials Ministry of EducationDepartment of Materials Science and EngineeringJilin UniversityChangchun 130022China

Organic electrode materials(OEMs)have attracted substantial attention for aqueous zinc-ion batteries(AZIBs)due to their advantages in relieving resource and environmental ***,the potential of OEMs is plagued by their low achievable capacity and high ***,we have proposed a new concept of“co-coordination force”and designed a rigid-flexible coupling crystalline polymer that can overcome the abovementioned *** obtained crystalline polymer(BQSPNs)with multiredox centres makes the BQSPNs exist intermolecular hydrogen bonds(HB)among-C=O,-C=N,and-NH and consequently exhibits transverse two-dimensional arrays and longitudinalπ-πstacking ***,in-situ FTIR,Raman,variable temperature FTIR spectra,and 2D nuclear overhauser effect spectroscopy(NOESY)well capture the existence and evolution process of HB during the electrochemistry reaction process of BQSPNs,uncovering the effect of HB in stabilizing the structure and promoting the reaction *** a result,the BQSPNs with rationally designed“co-coordination force”deliver a high capacity of 459.6 m Ah/g and a stable cycling lifetime for more than 100,000 cycles at 10 A/g in *** results disclose the HB effect and provide a brand-new strategy for high-performance OEMs design.

关键词： Co-coordination force Crystalline polymer Hydrogen bonds Organic electrode materials Aqueous zinc-ion batteries

Suppression of low-frequency ultrasound broadband vibration using star-shaped single-phase metamaterials

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Defence Technology（防务技术） 2024年第4期34卷 217-224页

作者： Rui Zhao Jian Zheng Jin guo Yunbo Shi Hengzhen Feng jun Tang jun liu Science and Technology on Electronic Test&Measurement Laboratory North University of ChinaTaiyuan 030051ShanxiChina School of Mechatronical Engineering Beijing Institute of TechnologyBeijing 100081China

In order to suppress the low-frequency ultrasound vibration in the broadband range of 20 k Hz—100 k Hz,this paper proposes and discusses an acoustic metamaterial with low-frequency ultrasound vibration attenuation properties,which is configured by hybrid arc and sharp-angle convergent star-shaped *** effect of the dispersion relation and the bandgap characteristic for the scatterers in star-shaped are simulated and *** target bandgap width is extended by optimizing the geometry parameters of arc and sharp-angle convergent *** proposed metamaterial configured by optimized hybrid lattices exhibits remarkable broad bandgap characteristics by bandgap complementarity,and the simulation results verify a 99%vibration attenuation amplitude can be obtained in the frequency of20 k Hz—100 k *** the fabrication of the proposed hybrid configurational star-shaped metamaterial by 3D printing technique,the transmission loss experiments are performed,and the experimental results indicate that the fabricated metamaterial has the characteristics of broadband vibration attenuation and an amplitude greater than 85%attenuation for the target *** results demonstrate that the hybrid configurational star-shaped metamaterials can effectively widen the bandgap and realize high efficiency attenuation,which has capability for the vibration attenuation in the application of highprecise equipment.

关键词： Star-shaped metamaterials Broadband Vibration attenuation Low-frequency ultrasound vibration Transmission loss

Emerging high-entropy strategy: A booster to the development of cathode materials for power batteries

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Journal of Advanced Ceramics 2024年第8期13卷 1093-1118页

作者： Liping Huang Jinging Zhu J-Xuan liu Houzheng Wu guo-jun Zhang State Key Laboratory for Modification of Chemical Fibers and Polymer Materials Institute of Functional MaterialsCollege of Materials Science and EngineeringDonghua UniversityShanghai 201620China SIAMC Advanced Materials Cooperation Huzhou 313100China

The coordinated development of new energy vehicles and the energy storage industry has become essential for reducing carbon *** cathode material is the key material that determines the energy density and cost of a power battery,but currently developed and applied cathode materials cannot meet the requirements for high specific capacity,low cost,safety,and good ***-entropy materials(HEMs)are a new type of single-phase material composed of multiple principal elements in equimolar or near-equimolar *** interaction between multiple elements can play an important role in improving the comprehensive properties of the material,which is expected to solve the limitations of battery materials in practical ***,this review provides a comprehensive overview of the current development status and modification strategies of power batteries(lithium-ion batteries(LiBs)and sodium-ion batteries(SIBs)),proposes a high-entropy design strategy,and analyses the structure-activity relationship between the high-entropy effects and battery ***,future research topics related to high-entropy cathode materials,including computational guide design,specific synthesis methods,high-entropy electrochemistry,and high-throughput databases,are *** review aims to provide practical guidance for the development of high-entropy cathode materials for next-generation power batteries.

关键词： cathode materials lithium-ion battery(LIB) sodium-ion battery(SIB) high-entropy strategy

A universal strategy of multi-objective active learning to accelerate the discovery of organic electrode molecules

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Science China Chemistry 2024年第11期67卷 3681-3687页

作者： Jiayi Du jun guo Wei liu Ziwei Li Gang Huang Xinbo Zhang State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied Chemistry Chinese Academy of Sciences School of Applied Chemistry and Engineering University of Science and Technology of China School of Materials Science and Engineering Changchun University of Science and Technology

Organic electrode molecules hold significant potential as the next generation of cathode materials for Li-ion batteries. In this study, we have introduced a multi-objective active learning framework that leverages Bayesian optimization and non-dominated sorting genetic algorithms-Ⅱ. This framework enables the selection of organic molecules characterized by high theoretical energy density and low gap(LUMO-HOMO)(LUMO, lowest unoccupied molecular orbital; HOMO, highest occupied molecular orbital). Remarkably, after only two cycles of active learning, the determination of coefficient can reach 0.962 for theoretical energy density and 0.920 for the gap with a modest dataset of 300 molecules, showcasing superior predictive capabilities. The 2,3,5,6-tetrafluorocyclohexa-2,5-diene-1,4-dione, selected by non-dominated sorting genetic algorithms-Ⅱ, has been successfully applied to Li-ion batteries as cathode materials, demonstrating a high capacity of 288 m Ah g-1and a long cycle life of 1,000 cycles. This outcome underscores the high reliability of our framework. Furthermore, we have also validated the universality and transferability of our framework by applying it to two additional databases, the QM9 and OMEAD. When the training dataset of the model includes at least 500 molecules, the determination of coefficient essentially reaches approximately0.900 for four targets: gap, reduction potential, LUMO, and HOMO. Therefore, the universal framework in our work provides innovative insights applicable to other domains to expedite the screening process for target materials.

关键词： organic electrode molecules Li-ion batteries active learning multi-objective Bayesian optimization

Estimating cropland carbon mitigation potentials in China affected by three improved cropland practices

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Journal of Mountain Science 2016年第10期13卷 1840-1854页

作者： LUN Fei Josep G.CANADELL HE Lu YANG Bo liu Mou-cheng YUAN Zheng TIAN Mi liu jun-guo LI Wen-hua School of Nature Conservation Beijing Forestry UniversityOinghua East Road 35Beijing 100083China College of Resources and Environment Sciences China Agricultural UniversityBeijing 100193China Center of Land Policy and Law Beijing 100193China Global Carbon Project CSIRO Marine and Atmospheric ResearchGPO Box 3023CanberraACT2601Australia World Natural Heritage Conservation and Research Center Ministry of Housing and Urban-RuralNo.9 SanliheBeijing 10085China Beijing Academy of Social Sciences No.33 BeisihuanzhongluBeijing 100101China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences11A Datun RoadBeijing 100101China. School of Environmental Science and Engineering South University of Science and Technology of ChinaShenzhen 518055China

Agriculture is a large source of carbon emissions. The cropland practices of fertilizer substitution, crop straw and conservation tillage are beneficial and help to rebuild local soil carbon stocks and reduce soil carbon emissions, in addition to reducing the consumption of fertilizers and fossil fuels. These improved cropland practices can directly and indirectly mitigatecarbon emissions, benefiting the sustainability of croplands. For these three improved practices, we estimated carbon mitigation potentials in rice, wheat and maize croplands in China. The combined contribution of these practices to carbon mitigation was 38.8 Tg C yr-1, with fertilizer substitution, crop straw return, and conservation tillage contributing 26.6, 3.6 and 8.6 Tg C yr-1, respectively. Rice, wheat and maize croplands had potentials to mitigate 13.4, 11.9 and 15.5 Tg C yr-1, respectively, with the combined direct and indirectpotential of 33.8 and 5.0 Tg C yr-1. Because of differences in local climate and specific diets, the regional cropland carbon mitigation potentials differed greatly among provinces in China. In China, 18 provinces had a "target surplus" for which the carbon mitigation from these three practices was larger than the mitigation target set for 2020. At the national level, a net "target surplus"of 4.84 Tg C yr-1 would be attained for Chinese croplands with full implementation of the three improved practices. Regional cooperation must be developed to achieve carbon mitigation targets using such measures as carbon trading, establishing regional associations, and strengthening research programs to improve practices.

关键词： Cropland Carbon mitigation potential Cropland practices Regional cooperation China