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优化附件对隐形矫治器乳牙固位力影响的生物力学初探

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中华口腔正畸学杂志 2024年第1期31卷 2-5页

作者：关万琅姜雯欣熊国平周俞辰暨南大学口腔医学院广州510000 深圳侨城菲诺口腔门诊部深圳518038 深圳市人民医院暨南大学第二临床医学院南方科技大学第一附属医院口腔正畸科深圳518020

目的研究不同附件形状设计对无托槽隐形矫治器固位力的影响。方法本研究为随机对照研究,制作下颌标准替牙列早期阳膜及相应不同附件设计的无托槽隐形矫治器,附件均放置在乳尖牙及第一乳磨牙颊侧中央位置,根据附件设计分为传统附件组和... 详细信息

目的研究不同附件形状设计对无托槽隐形矫治器固位力的影响。方法本研究为随机对照研究,制作下颌标准替牙列早期阳膜及相应不同附件设计的无托槽隐形矫治器,附件均放置在乳尖牙及第一乳磨牙颊侧中央位置,根据附件设计分为传统附件组和强固位附件组,再按照常用的附件形状进行分组:对照组(传统附件组):A1组:水平矩形传统附件矫治器;B1组:垂直矩形传统附件矫治器;C1组:椭圆形传统附件矫治器;实验组(强固位附件组):A2组:水平矩形强固位附件矫治器;B2组:垂直矩形强固位附件矫治器;C2组:椭圆形强固位附件矫治器,每组各1例。利用万能材料试验机测试在下颌乳尖牙颊侧脱位时的矫治器固位力大小,每组脱位10次,分别采用独立样本t检验及Mann-Whitney U检验对两组间固位力大小的差异进行统计学分析。结果在下颌乳尖牙颊侧脱位时,A2组固位力的中位数较A1组高[A1:14.06(13.85,14.27)N,A2:15.07(14.67,16.14)N],且差异均有统计学意义(P<0.001);B2组的固位力均值大于B1组[B1:(12.70±0.52)N,B2:(15.51±1.43)N],且差异有统计学意义(P<0.001);而C2组固位力的中位数与C1组间差异无统计学意义[C1:13.03(12.28,13.28)N,C2:14.15(13.09,14.31)N,P=0.075]。结论水平矩形、垂直矩形强固位附件均能显著提高隐形矫治器的固位力。而椭圆形强固位附件与传统椭圆形附件间无明显差异。

关键词：无托槽隐形矫治器附件固位力

亮斑扁角水虻幼虫生物转化对鸡粪中FAdV-4的消减作用研究

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化学与生物工程 2024年第1期41卷 21-27页

作者：陈帅严婷婷董梦瑶周煜琛佘望军李月蔡珉敏黄凤张吉斌喻子牛郑龙玉华中农业大学湖北武汉430070

将亮斑扁角水虻幼虫(black soldier fly larvae,BSFL)接入含禽腺病毒血清4型(FAdV-4)的鸡粪中(0~18 d),采用TaqMan qPCR和16S rDNA高通量测序分析了BSFL转化过程中FAdV-4含量的动态变化和微生物区系演化。结果表明,BSFL转化能够显著消... 详细信息

将亮斑扁角水虻幼虫(black soldier fly larvae,BSFL)接入含禽腺病毒血清4型(FAdV-4)的鸡粪中(0~18 d),采用TaqMan qPCR和16S rDNA高通量测序分析了BSFL转化过程中FAdV-4含量的动态变化和微生物区系演化。结果表明,BSFL转化能够显著消减鸡粪中的FAdV-4群体载量,转化18 d时FAdV-4减少率达到了99.63%,明显高于对照组(64.74%),并且增加BSFL接种量和日龄能增强对FAdV-4的消减作用;BSFL转化使得物料中的细菌多样性显著降低;厚壁菌门、假单胞菌属受到抑制,而拟杆菌门、异常球菌-栖热菌门丰度则明显提高;居绿藻菌属、特吕珀菌属在BSFL转化体系中与FAdV-4消减密切相关。

关键词：亮斑扁角水虻鸡粪禽腺病毒血清4型生物转化 16S rDNA测序

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

Nickel-modified In_(2)O_(3) with inherent oxygen vacancies for CO_(2) hydrogenation to methanol

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Science China Chemistry 2024年第5期67卷 1715-1728页

作者： Zixuan zhou yuchen Wang Yuanjie Bao Haiyan Yang Jiong Li Chunran Chang Shenggang Li Peng Gao CAS Key Laboratory of Low-Carbon Conversion Science and Engineering Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201210China University of Chinese Academy of Sciences Beijing 100049China School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China Shaanxi Key Laboratory of Low Metamorphic Coal Clean Utilization School of Chemistry and Chemical EngineeringYulin UniversityYulin 719000China

Methanol synthesis is one of the most important industrially-viable approaches for carbon dioxide(CO_(2)) utilization, as the produced methanol can be used as a platform chemical for manufacturing green fuels and chemicals. The In_(2)O_(3) catalysts are ideal for sustainable methanol synthesis and have received considerable attention. Herein, Co-, Ni-and Cu-modified In_(2)O_(3) catalysts were fabricated with high dispersion and high stability to improve the hydrogenation performance. The Ni-promoted In_(2)O_(3) catalyst in the form of high dispersion possessed the largest amount of oxygen vacancies and the strongest ability for H_(2) activation, leading to the highest CO_(2) conversion and space time yield of methanol of 0.390 g_(Me OH)g_(cat)^(-1)h^(-1) with CH_(3)OH selectivity of 68.7%. In addition, the catalyst exhibits very stable performance over 120 h on stream, which suggests the promising prospect for industrial applications. Further experimental and theoretical studies demonstrate that surface Ni doping promotes the formation of oxygen defects on the In_(2)O_(3) catalyst, although it also results in lower methanol selectivity. Surprisingly, subsurface Ni dopants are found to be more beneficial for methanol formation than surface Ni dopants, so the Nipromoted In_(2)O_(3)catalyst with a lower surface Ni content at the similar Ni loading can reach higher methanol selectivity and productivity. This work thus provides theoretical guidance for significantly improving the CO_(2) reactivity of In_(2)O_(3)-based catalysts while maintaining high methanol selectivity.

关键词： carbon dioxide hydrogenation methanol synthesis indium oxides Ni doping sites transition metal promoters

Credibility Evaluation of Hardware-in-the-Loop Simulation Systems

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Credibility Evaluation of Hardware-in-the-Loop Simulation Sy...

Improved Visual Odometer Based on Two-stream Convolutional Neural Networks

第30届中国控制与决策会议

作者： Ke Fang yuchen zhou Ping Ma Ming Yang Control and Simulation Center Harbin Institute of Technology

Hardware-in-the-loop Simulation Systems（HILSS） provide effective platforms for the test of hardware and software. To guarantee the correct application of HILSS, comprehensive credibility evaluation should be implemented over the system development life cycle. The components and general structure of HILSS are discussed and the similarity types in HILSS are classified into time ＆ logical similarity, geometry similarity, dynamic characteristic similarity and perceptual information similarity. Based on the previous formulation, the factor space construction approaches for simulation models, physical effect simulators, and test components are explained. Finally, a systematic credibility evaluation factor space of the HILSS for guidance and control simulation of flight vehicle is built. The study reveals that factor space provides an explicit path for the credibility evaluation of complicated simulation systems.

关键词： Hardware-in the-loop Simulation Systems Credibility Evaluation Life Cycle Evaluation Process Factor Space Verification ＆ Validation

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Improved Visual Odometer Based on Two-stream Convolutional N...

第40届中国控制会议

作者： yuchen zhou Guan Lu Xi Chen Yiming Xu Li Wang College of Mechanical Engineering Nantong university College of Electrical Engineering Nantong university

The purpose of the visual odometer is to use the image information input by the camera to estimate the motion information of the camera.As a positioning method,it has been widely used in fields such as autonomous driving and mobile robots in recent years.Because of the disadvantages of traditional visual odometers such as cumbersome implementation process and complicated calculation,the improvement of visual odometers has always been a hot research topic.In this paper,a twostream convolutional neural networks is used,while RGB images and depth images are input to the model for training,and the Inception module is used to improve the convolutional layer and reduce the number of parameters.At the same time,an attention model is added to the convolutional layer to improve the network’s recognition of image features and the robustness of the system.Finally,the model was trained and tested on the KITTI data set.The results show that the model we proposed has achieved a certain improvement compared with VISO2-M and SfMLearner.

关键词： Computer vision Deep learning Visual odometer Attention mechanism

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论宗教神秘本质及诸因素的运演机制

世界宗教文化 2023年第5期 126-134页

作者：周普元周煜宸新疆师范大学政法学院新疆师范大学政法学院新疆宗教研究中心

神秘是宗教的根基,它只能被感知但不可描述、“不可言说”,是一种逃避理性意识的“被遮蔽”的非理性体验。奥托运用宗教现象学的理论和方法,把宗教“不可言说”的形而上学实体存在论,转化为一种主体的意识分析和生存主义的诠释学说。根... 详细信息

神秘是宗教的根基,它只能被感知但不可描述、“不可言说”,是一种逃避理性意识的“被遮蔽”的非理性体验。奥托运用宗教现象学的理论和方法,把宗教“不可言说”的形而上学实体存在论,转化为一种主体的意识分析和生存主义的诠释学说。根据精神分析学潜意识理论,神秘居于潜意识层,是无法被理性所把握的非理性,它只能通过理性的被意识化的神圣来展现自身。神秘呈现神圣,而神圣遮蔽神秘,唯有通过凝视自为的神圣去还原自在的神秘,才能“回到事实本身”。

关键词：宗教现象学宗教心理学神秘神圣

Nickel-modified InOwith inherent oxygen vacancies for COhydrogenation to methanol

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Science China Chemistry 2024年

作者： Zixuan zhou yuchen Wang Yuanjie Bao Haiyan Yang Jiong Li Chunran Chang Shenggang Li Peng Gao University of Chinese Academy of Sciences School of Physical Science and Technology ShanghaiTech University Shanghai Synchrotron Radiation Facility Shanghai Advanced Research Institute Chinese Academy of Sciences Shaanxi Key Laboratory of Low Metamorphic Coal Clean Utilization School of Chemistry and Chemical Engineering Yulin University CAS Key Laboratory of Low-Carbon Conversion Science and Engineering Shanghai Advanced Research Institute Chinese Academy of Sciences

Methanol synthesis is one of the most important industrially-viable approaches for carbon dioxide (CO2) utilization,as the produced methanol can be used as a platform chemical for manufacturing green fuels and chemicals.The In2O3catalysts are ideal for sustainable methanol synthesis and have received considerable attention.Herein,Co-,Ni-and Cu-modified In2O3catalysts were fabricated with high dispersion and high stability to improve the hydrogenation performance.The Ni-promoted In2O3catalyst in the form of high dispersion possessed the largest amount of oxygen vacancies and the strongest ability for H2activation,leading to the highest CO2conversion and space time yield of methanol of 0.390 gMeOHg-1cath-1with CH3OH selectivity of 68.7%.In addition,the catalyst exhibits very stable performance over 120 h on stream,which suggests the promising prospect for industrial applications.Further experimental and theoretical studies demonstrate that surface Ni doping promotes the formation of oxygen defects on the In2O3catalyst,although it also results in lower methanol selectivity.Surprisingly,subsurface Ni dopants are found to be more beneficial for methanol formation than surface Ni dopants,so the Nipromoted In2O3catalyst with a lower surface Ni content at the similar Ni loading can reach higher methanol selectivity and productivity.This work thus provides theoretical guidance for significantly improving the CO2reactivity of In2O3-based catalysts while maintaining high methanol selectivity.

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面向多用户NOMA-IRS系统的公平性优化

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西安电子科技大学学报 2023年第2期50卷 1-10页

作者：韩永康陈健周雨晨杨龙西安电子科技大学通信工程学院陕西西安710071

多用户非正交多址接入-智能反射面系统,可通过多天线发射机与智能反射面间“发射-反射”联合波束成形,改善系统的用户接入能力。针对多用户非正交多址接入-智能反射面系统用户公平性问题,尝试在射频链路受限的实际场景中,最大限度提升... 详细信息

多用户非正交多址接入-智能反射面系统,可通过多天线发射机与智能反射面间“发射-反射”联合波束成形,改善系统的用户接入能力。针对多用户非正交多址接入-智能反射面系统用户公平性问题,尝试在射频链路受限的实际场景中,最大限度提升用户最小接收信干噪比,从而无差别地保证各用户的通信质量。为此,根据射频链路数对用户进行分簇,构建了最大-最小接收信干噪比分式规划问题,此问题的发射波束矢量与反射阵元矩阵在接收信干噪比处高度耦合。因此,提出了一种基于半定松弛与算术几何平均算法,通过在每次迭代中交替优化发射波束矢量与反射阵元矩阵,实现各簇中最小信道容量的最大化。并进一步采用二分搜索算法求解簇内功率分配问题,以提升用户最小接收信干噪比。仿真结果表明,相对于迫零方案,提出方案能够以较低的计算复杂度提升用户最小接收信干噪比,从而改善各用户通信质量;且区别于最大比传输方案,提出方案中用户最小接收信干噪比不会随基站发射功率增加而呈现饱和现象,从而实现各用户通信质量的稳定增长。

关键词：非正交多址接入智能反射面公平性用户分簇波束成形资源分配