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An adaptive sequential experiment design method for model validation

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Chinese Journal of Aeronautics 2020年第6期33卷 1661-1672页

作者： ke fang Yuchen ZHOU Ping MA Control and Simulation Center Harbin Institute of TechnologyHarbin 150080China

Efficient experiment design is of great significance for the validation of simulation model with high nonlinearity and large input *** validation experiment raises the cost while insufficient test increases the risks of accepting an invalid *** this paper,an adaptive sequential experiment design method combining global exploration criterion and local exploitation criterion is *** exploration criterion utilizes discrepancy metric to improve the space-filling property of the design points while the exploitation criterion employs the leave one out error to discover informative *** avoid the clustering of samples in the local region,an adaptive weight updating approach is provided to maintain the balance between exploration and ***,the credibility distribution function characterizing the relationship between the input and result credibility is introduced to support the model validation experiment ***,six benchmark problems and an engineering case are applied to examine the performance of the proposed *** experiments indicate that the proposed method achieves satisfactory performance for function approximation in accuracy and convergence.

关键词： Adaptive sequential experiment design Credibility distribution function Gaussian process model Metamodeling Model validation

教育数字化背景下高校思政课精准教学模式探析

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湖北开放职业学院学报 2025年第2期38卷 157-159页

作者：刘克方陈猛湖南科技学院马克思主义学院湖南永州425199

新一代数字技术迅猛发展和日益普及,对数字时代教育新形态提供了新的支撑。探索教育数字化背景下高校思政课精准教学的路径模式成为当下教育的重要议题。实施高校思政课精准教学具有顺应数字教育时代教学改革的需要、促进高校思政课提... 详细信息

新一代数字技术迅猛发展和日益普及,对数字时代教育新形态提供了新的支撑。探索教育数字化背景下高校思政课精准教学的路径模式成为当下教育的重要议题。实施高校思政课精准教学具有顺应数字教育时代教学改革的需要、促进高校思政课提质增效、迎合大学生主体个性化成长需要等现实意蕴。但当下思政课精准教学存在教学资源需求无限性与教学资源供给有限性、教学过程经验性与教学实施精准性和教学评价单一性与教学目标多元性等一系列矛盾。通过精准学情识别、精准内容供给、精准设计教学过程和精准教学评价,助力教育数字化背景下高校思政课精准教学的实施,为构建数字技术赋能下思想政治理论课守正创新的新途径提供参考。

关键词：教育数字化高校思想政治理论课精准教学教学模式

Validation method for simulation models with cross iteration

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Journal of Systems Engineering and Electronics 2019年第3期30卷 555-563页

作者： fang ke ZHAO Kaibin ZHOU Yuchen Control and Simulation Center Harbin Institute of Technology

Cross iteration often exists in the computational process of the simulation models, especially for control models. There is a credibility defect tracing problem in the validation of models with cross iteration. In order to resolve this problem, after the problem formulation, a validation theorem on the cross iteration is proposed, and the proof of the theorem is given under the cross iteration circumstance. Meanwhile, applying the proposed theorem, the credibility calculation algorithm is provided, and the solvent of the defect tracing is explained. Further, based on the validation theorem on the cross iteration, a validation method for simulation models with the cross iteration is proposed, which is illustrated by a flowchart step by step. Finally, a validation example of a sixdegree of freedom (DOF) flight vehicle model is provided, and the validation process is performed by using the validation method. The result analysis shows that the method is effective to obtain the credibility of the model and accomplish the defect tracing of the validation.

关键词： validation method simulation model cross iteration validation theorem validation example

Analysis and Inverse Substructuring Computation on Dynamic Quality of Mechanical Assembly

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Chinese Journal of Mechanical Engineering 2016年第3期29卷 539-548页

作者： Lü Guangqing YI Chuijie fang ke key Lab of Disasters Forecast and Control in Engineering of Ministry of Education Jinan University Research Center of Equipment Energy & Environment Qingdao Technological University

Mechanical assembly has its own dynamic quality directly affecting the dynamic quality of whole product and should be considered in quality inspection and estimation of mechanical assembly. Based on functional relations between dynamic characteristics involved in mechanical assembly, the effects of assembling process on dynamic characteristics of substructural components of an assembly system are investigated by substructuring analysis. Assembly-coupling dynamic stiffness is clarified as the dominant factor of the effects and can be used as a quantitative measure of assembly dynamic quality. Two computational schemes using frequency response functions（FRFs） to determine the stiffness are provided and discussed by inverse substructuring analysis, including their applicable conditions and implementation procedure in application. Eigenvalue analysis on matrix-ratios of FRFs before and after assembling is employed and well validates the analytical outcomes and the schemes via both a lumped-parameter model and its analogic experimental counterpart. Applying the two schemes to inspect the dynamic quality provides the message of dynamic performance of the assembly system, and therefore improves conventional quality inspection and estimation of mechanical assembly in completeness.

关键词： mechanical assembly dynamic quality substructuring analysis inverse substructuring assembly-coupling dynamic stiffness

The Transformation of Rural Household Reproduction Model and Its Impact on Family Relations

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学术界 2019年第6期 193-203页

作者： ke fang School of Marxism Southwest Jiaotong University School of Marxism Chongqing University of Technology

Under the pressure of marketization and urbanization,rural family reproduction mode has transformed from simple reproduction to expanded family reproduction,thus changing the family structure and family *** the mode of expanded family reproduction,family relationship is a highly rational and deeply mobilized interaction *** the family element configuration profoundly reflects the practical form of family *** the mode of expanded family reproduction,the changes in rural family relations are mainly reflected in three aspects:the decline of the paternal authority and the increasing family status of the offspring;the increasing status of women along with a decisive role in family decision-making;the more independent,equal,competitive and rational relationship among *** changes bring forward new requirements on rural governance system,which requires improvements on social security and public culture.

关键词： simple family reproduction expanded family reproduction family relationship rural governance

Flexibility as a Strategy for Avoiding Call Overlap in Male Anhui Treefrogs

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Asian Herpetological Research 2020年第3期11卷 230-239页

作者： Jinjin SONG Ruolei SUN ke fang Baowei ZHANG Yezhong TANG Guangzhan fang School of Life Science Anhui UniversityHefei 230601AnhuiChina Chengdu Institute of Biology Chinese Academy of SciencesChengdu 610041SichuanChina Institute of Bio-inspired Structure and Surface Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016JiangsuChina

Male-male vocal competition is critical for mating success in anuran species;however,it remains unknown that how males regulate their competitive strategies dynamically during competition because calling is highly time-consuming,energetically demanding and likely to increase predation *** different parts of calls will encode different information for vocal communication,we hypothesized that competitive strategies of male frogs may be modulated by the temporal and spectral features of different call *** test this hypothesis,the natural advertisement calls(OC),its modified versions with the first call note replaced by white noise(WN)or other notes and with the fifth call note replaced by WN,were played back to the Anhui tree frogs(Rhacophorus zhoukaiyae).Results showed that 1)males produced more competitive calls in response to acoustic stimuli compared to their baseline calling during silence;and 2)males emitted more non-overlapping calls compared to overlapping calls in response to the acoustic *** results are consistent with the idea that males are flexible to acoustic signals and their competition strategies are modulated dynamically by social contexts.

关键词： acoustic stimulus call overlap flexibility frog individual recognition male-male competition

Partial Oxidation of Toluene on VO_x-TiO_x/SBA-15

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Chemical Research in Chinese Universities 2009年第6期25卷 924-928页

作者： fang ke-gong WANG Bin SUN Yu-han State key Laboratory of Coal Conversion Institute of Coal Chemistry Chinese Academy of Sciences Taiyuan 030001 P. R. China

A series of VOx-TiOx/SBA-15 catalysts was rized by different techniques such as N2-sorption, TPR prepared by the grafting method. The catalysts were characte- UV-Vis and NH3-TPD in order to verify the vanadium and titanium species, and their catalytic properties were investigated for the partial oxidation of toluene. The results show that vanadium mainly existed in the forms of isolated tetrahedral and octahedral species at the low loadings. The introduction of a certain amount of titanium improved the dispersion of vanadium on the support and then the catalytic performance for toluene oxidation at the same vanadium content. Both toluene conversion and benzaldehyde selectivity, showed the maximum values and then decreased with increasing the amount of titanium in the catalyst.

关键词： Vanadium Titanium Partial oxidation Toluene Benzaldehyde

Hierarchical auditory perception for species discrimination and individual recognition in the music frog

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Current Zoology 2022年第5期68卷 581-591页

作者： Yanzhu Fan ke fang Ruolei Sun Di Shen Jing Yang Yezhong Tang Guangzhan fang Chengdu Institute of Biology Chinese Academy of SciencesChengdu 610041China College of Life Sciences University of Chinese Academy of SciencesBeijing 100049China School of Life Science Anhui UniversityHefei 230601China

The ability to discriminate species and recognize individuals is crucial for reproductive success and/or survival in most ***,the temporal order and neural localization of these decision-making processes has remained *** this study,event-related potentials(ERPs)were measured in the telencephalon,diencephalon,and mesencephalon of the music frog Nidirana *** ERPs were elicited by calls from 1 group of heterospecifics(recorded from a sympatric anuran species)and 2 groups of conspecifics that differed in their fundamental *** terms of the polarity and position within the ERP waveform,auditory ERPs generally consist of 4 main components that link to selective attention(N1),stimulus evaluation(P2),identification(N2),and classification(P3).These occur around 100,200,250,and 300 ms after stimulus onset,*** results show that the N1 amplitudes differed significantly between the heterospecific and conspecific calls,but not between the 2 groups of conspecific calls that differed in fundamental *** the other hand,the N2 amplitudes were significantly different between the 2 groups of conspecific calls,suggesting that the music frogs discriminated the species first,followed by individual identification,since N1 and N2 relate to selective attention and stimuli identification,***,the P2 amplitudes evoked in females were significantly greater than those in males,indicating the existence of sexual dimorphism in auditory *** addition,both the N1 amplitudes in the left diencephalon and the P2 amplitudes in the left telencephalon were greater than in other brain areas,suggesting left hemispheric dominance in auditory *** together,our results support the hypothesis that species discrimination and identification of individual characteristics are accomplished sequentially,and that auditory perception exhibits differences between sexes and in spatial dominance.

关键词： event-related potentials(ERPs) individual identification music frog species discrimination temporal hierarchy

Synthesization and crystallization mechanism of nano-scale γ-AlOOH with various morphologies

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International Journal of Minerals,Metallurgy and Materials 2010年第3期17卷 376-379页

作者： Bao-hong Hao ke-ming fang Lan Xiang Qiang Liu School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing 100083 China Department of Mechanical Engineering Beijing Institute of Petrochemical Technology Beijing 102617 China Department of Chemical Engineering T singhua University Beijing 100084 China

Nano-scale γ-AIOOH with various morphologies, such as whisker, bar, ball, and sheet, was synthesized successfully and control- lably through a facile hydrothermal method just by adjusting the pH value of the solvent. Based on the analysis of the experimental data, the growth mechanism of nano-scale γ-AlOOH in the hydrothermal process was established. It is proposed that the growth unit and the growth direction are determined by the pH value of the solution and the growth unit, respectively. One-dimensional γ-AlOOH, such as whisker and bar, is formed in lower pH ranges, while two-dimensional γ-AlOOH sueli as sheet is formed only in high pH environment following the plane expansion crystallization mechanism.

关键词： boehmite morphology control crystallization mechanism growth unit aggregate