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Some convergence theorems of fuzzy concave integral on fuzzyσ-algebra

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Applied Mathematics(A Journal of Chinese Universities) 2024年第3期39卷 438-447页

作者： sun Rong School of Mathematics and Statistics Chongqing Technology and Business UniversityChongqing 400067China Chongqing Key Laboratory of Statistical Intelligent Computing and Monitoring Chongqing Technology and Business UniversityChongqing 400067China

In this paper,we consider the extension of the concave integral from classical crispσ-algebra to fuzzyσ-algebra of fuzzy ***,the concept of fuzzy concave integral on a fuzzy set is ***,some important properties of s... 详细信息

关键词： convergence theorems fuzzy concave integral fuzzyσ-algebra

Molecular Chaperone-Dependent Polymer Translocation through Nanopores: The Effects of Chaperone Concentration and Chaperone-Polymer Interaction

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Chinese Journal of Polymer Science 2024年第1期42卷 125-132,I0011页

作者： Chang-Sheng Zuo Kang Wang Li-Zhen sun Ting-Ting sun Department of Physics Zhejiang University of Science and TechnologyHangzhou 310023China Department of Applied Physics Zhejiang University of TechnologyHangzhou 310014China

The polymer translocation through a nanopore from a donor space(or named cis side) to a receiver space(trans side) in the chaperone-induced crowded environment has attracted increasing attention in recent years due to its significance in biological systems and technological applications. In this work, we mainly focus on the effects of chaperone concentration and chaperone-polymer interaction on the polymer translocation. By assuming the polymer translocation to be a quasi-equilibrium process, the free energy F of the polymer can be estimated by Rosenbluth-Rosenbluth method and then the translocation time τ can be calculated by Fokker-Plank equation based on the obtained free energy landscape. Our calculation results show that the translocation time can be controlled by independently tuning the chaperone concentration and chaperone-polymer interaction at the cis side or the trans side. There exists a critical chaperone-polymer attraction ε~*=-0.2 at which the volume exclusion and interaction effects of the chaperone can balance each other. Additionally, we also find that at large chaperone-polymer attraction, the translocation time is mainly governed by the diffusion coefficient of the polymer.

关键词： Polymer translocation Rosenbluth-Rosenbluth method Fokker-Plank equation Free energy landscapes

Catalyst design and structure control for photocatalytic refineries of cellulosic biomass to fuels and chemicals

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Journal of Energy Chemistry 2024年第7期94卷 102-127页

作者： Lulu sun Nengchao Luo State Key Laboratory of Catalysis Dalian National Laboratory for Clean EnergyDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina

Lignocellulosic biomass is the largest renewable hydrocarbon resource on *** cellulose,one of the major components of lignocellulose,powered by solar energy is a promising way of providing lowcarbon-footprint energy chemicals such as H_(2),HCOOH,CO,and transportation ***-of-the-art biorefineries target the full use of biomass feedstocks as they have a maximum collection radius of 75-100 km,requesting efficient and selective photocatalysts that significantly influence the outcome of photocatalytic ***-performed photocatalysts can harvest a broad solar spectrum and are active in breaking the chemical bonds of cellulose,decreasing the capital investments of ***,photocatalysts should control the selectivity of cellulose conversion,originating target products to level down separation *** separation in photocatalysts and interfacial charge transfer between photocatalysts and cellulose affect the activity and selectivity of cellulose refineries to H2 and carbonaceous *** account for the challenges above,this review summarizes photocatalysts for the refineries of cellulose and downstream platform molecules based on the types of products,with the structure features of different types of photocatalysts discussed in relation to the targets of either improving the activity or product *** addition,this review also sheds light on the methods for designing and regulating photocatalyst structures to facilitate photocatalytic refineries of cellulose and platform molecules,meanwhile summarizing proposed future research challenges and opportunities for designing efficient photocatalysts.

关键词： Photocatalysts Biorefineries Cellulose Fuels Hydrogen

Blindness-free beam scanning antenna with array of array architecture: principle,design,and experiment

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Science China(Information Sciences) 2024年第3期67卷 209-224页

作者： Jianxu sun Yujian CHENG School of Electronic Science and Engineering University of Electronic Science and Technology of China

This paper presents a 66–76-GHz sparsely-excited phased array antenna with the array of array(Ao A) architecture for eliminating the blindness and suppressing the grating lobe when scanning. For the array antennas printed on the thick dielectric layers with high relative permittivity, scanning blindness appears and seriously impacts the radiation performance. To address this issue, the Ao A topology is developed first. It finds that the scanning blindness appears due to the coupling of the radiating Floquet modes to the non-radiating surface wave(SW) modes. Therefore, the array is divided into two types of domino *** inner-phase distributions are introduced into the domino subarrays to break the one-to-one relationship between the Floquet mode and the SW mode. Then, the blindness inside ±60° scanning volume is eliminated by the aperiodic subarrays. Meanwhile, the aperiodic inner-phase distributions enhance the aperiodicity of the array and contribute to suppressing the grating lobe when scanning. Next, the meta-surface-based dipole with the shorted post is chosen as the unit cell for the proposed aperiodic array. Based on these methods,the array achieves the wide-scanning performance of ±60° in the E-plane and ±30° in the H-plane, without the blindness and the grating lobe. Finally, the 16×16 array is built and simulated with the dimension of32 mm × 32 mm. At the highest operating frequency, the simulated gains are 28.42, 25.17, and 24.01 d Bi when scanning to the broadside, 50° in the E-plane, and 30° in the H-plane, respectively. Compared to the ideal gain, it shows that the simulated radiation efficiency is about 84.13%, 62.08%, and 35.23% when scanning to the broadside, 50° in the E-plane, and 30° in the H-plane, respectively. The worst transmission coefficient, i.e., the worst isolation, is-11.97 d B between the central element and its two adjacent elements in the E-plane. The array prototypes are fabricated, and the experiments are carried out to ver

关键词： 6G communication systems phased array AoA aperiodic subarray wideband wide-scanning surface-wave scanning blindness grating lobe

Self-Aligning Multi-Modal Transformer for Oropharyngeal Swab Point Localization

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Tsinghua Science and Technology 2024年第4期29卷 1082-1091页

作者： Tianyu Liu Fuchun sun Department of Computer Science and Technology Tsinghua UniversityBeijing 100083China

The oropharyngeal swabbing is a pre-diagnostic procedure used to test various respiratory diseases, including COVID and Influenza A (H1N1). To improve the testing efficiency of testing, a real-time, accurate, and robust sampling point localization algorithm is needed for robots. However, current solutions rely heavily on visual input, which is not reliable enough for large-scale deployment. The transformer has significantly improved the performance of image-related tasks and challenged the dominance of traditional convolutional neural networks (CNNs) in the image field. Inspired by its success, we propose a novel self-aligning multi-modal transformer (SAMMT) to dynamically attend to different parts of unaligned feature maps, preventing information loss caused by perspective disparity and simplifying overall implementation. Unlike preexisting multi-modal transformers, our attention mechanism works in image space instead of embedding space, rendering the need for the sensor registration process obsolete. To facilitate the multi-modal task, we collected and annotate an oropharynx localization/segmentation dataset by trained medical personnel. This dataset is open-sourced and can be used for future multi-modal research. Our experiments show that our model improves the performance of the localization task by 4.2% compared to the pure visual model, and reduces the pixel-wise error rate of the segmentation task by 16.7% compared to the CNN baseline.

关键词： segmentation localization transformer multi-modal perception robotic perception

显式分析方法在高层建筑弹塑性地震反应分析中的适用性研究

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地震工程与工程振动 2015年第4期35卷 85-93页

作者：杜轲孙景江丁宝荣刘仲伟中国地震局工程力学研究所中国地震局地震工程与工程振动重点实验室黑龙江哈尔滨150080

目前隐式方法是动力弹塑性时程分析最常用的分析方法,然而隐式方法在强非线性分析中常常存在迭代不收敛的问题,并且刚度矩阵求解消耗的存储空间随结构自由度增加呈几何级数增长。因此,在求解高层建筑这种大规模问题中,极易遭遇计算瓶颈... 详细信息

目前隐式方法是动力弹塑性时程分析最常用的分析方法,然而隐式方法在强非线性分析中常常存在迭代不收敛的问题,并且刚度矩阵求解消耗的存储空间随结构自由度增加呈几何级数增长。因此,在求解高层建筑这种大规模问题中,极易遭遇计算瓶颈。显式分析方法直接求解解耦的方程组,不需要迭代。本文对隐式方法和显式方法进行了对比分析,研究了显式分析方法在高层建筑弹塑性地震反应分析中适用性。实例分析表明,从计算精度来讲,隐式方法和显式方法在稳定条件下都能得到较好的精度。从计算效率来讲,对于自由度较少的结构,隐式方法计算效率较高;对于自由度庞大的结构,显式方法计算效率较高。建议在进行自由度多的高层建筑弹塑性地震反应分析时,采用显式分析方法。

关键词：显式分析方法高层建筑弹塑性地震反应分析计算精度计算效率

应用烈度衰减关系进行烈度分布快速评估的偏差特性研究

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世界地震工程 2012年第4期28卷 100-104页

作者：许卫晓孙景江杨伟松丁宝荣中国地震局工程力学研究所中国地震局地震工程与工程振动重点实验室黑龙江哈尔滨150080

地震发生后,一般都是用烈度衰减关系来初步评估烈度分布。为了研究该方法的偏差特性,首先利用138次地震事件回归出我国大陆地区的烈度衰减关系,然后应用该衰减关系,以我国大陆地区1966年以来震级在6.0级以上的43次地震事件的评估结果,... 详细信息

地震发生后,一般都是用烈度衰减关系来初步评估烈度分布。为了研究该方法的偏差特性,首先利用138次地震事件回归出我国大陆地区的烈度衰减关系,然后应用该衰减关系,以我国大陆地区1966年以来震级在6.0级以上的43次地震事件的评估结果,总结出应用烈度衰减关系评估烈度分布时的偏差特性,并提出了相应的改进建议。

关键词：灾情评估地震烈度衰减关系等震线

Effect of wire mesh casing treatment on axial compressor performance and stability

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Chinese Journal of Aeronautics 2024年第3期37卷 60-76页

作者： Ming ZHANG Jiaming ZHANG Jiahao HU Xu DONG Dakun sun Xiaofeng sun School of Energy and Power Engineering Beihang UniversityBeijing 100191China Beihang Hangzhou Innovation Institute Yuhang Hangzhou 310023China National Key Laboratory of Science and Technology on Aero-Engine Aero-Thermodynamics Beihang UniversityBeijing 100191China

In this paper,a kind of Wire Mesh Casing Treatment(WMCT)is proposed to improve the stable operating range of the *** contrast to the traditional circumferential groove,as for WMCT,a layer of wire mesh is laid on the surface of the circumferential *** studies were conducted on the low-speed axial flow compressor,including the groove width,axial location,and mesh *** optimum axial location for WMCT is related to its groove width.A higher wire mesh count results in a smaller compressor stall margin *** simulations were carried out to study the effect of WMCT on the flow structure of the *** wire mesh in the WMCT has a certain flow resistance,which restricts the flow into and out of the *** to the WMCT,the flow parameter in the tip region of the rotor is less sensitive to changes in the operating conditions of the *** WMCT causes the rotor tip blade loading to shift backward,inhibiting the formation of spill forward of the leakage flow,and thus improving the stability of the *** flow resistance on the groove surface is a new degree-of-freedom for the casing treatment designer.

关键词： Axial compressor Wire mesh casing treatment Tip clearance flow Stall margin Blade loading

Persistent Variations in the East Asian Trough from March to April and the Possible Mechanism

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Advances in Atmospheric Sciences 2024年第4期41卷 737-753,I0002-I0004页

作者： Shui YU Jianqi sun Nansen-Zhu International Research Center Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China

The East Asian trough(EAT)profoundly influences the East Asian spring *** this study,the relationship of the EATs among the three spring months is *** analysis shows that the variation in March EAT is closely related to that of April *** empirical orthogonal function(EEOF)analysis also confirms the co-variation of the March and April *** positive/negative EEOF1 features the persistent strengthened/weakened EAT from March to *** investigation indicates that the variations in EEOF1 are related to a dipole sea surface temperature(SST)pattern over the North Atlantic and the SST anomaly over the tropical Indian *** dipole SST pattern over the North Atlantic,with one center east of Newfoundland Island and another east of Bermuda,could trigger a Rossby wave train to influence the EAT in March−*** SST anomaly over the tropical Indian Ocean can change the Walker circulation and influence the atmospheric circulation over the tropical western Pacific,subsequently impacting the southern part of the EAT in March−*** the SST factors,the Northeast Asian snow cover could change the regional thermal conditions and lead to persistent EAT anomalies from March to *** three impact factors are generally independent of each other,jointly explaining large variations in the EAT ***,the signals of the three factors could be traced back to February,consequently providing a potential prediction source for the EAT variation in March and April.

关键词： spring East Asian trough sea surface temperature snow cover