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6G；广域覆盖信令小区；多维资源分配；深度Q网络（DQN） 1

LoRa 1

N-糖基化 1

NB-IoT 1

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串并联谐振变换器；全桥；半桥；变频；移相；宽范围输入电压 1

低角估计；甚高频雷达；复杂场景；多径效应；高度估计 1

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剪切应变 1

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单站；结构总体最小二乘；逆迭代；到达角（AOA）；到达时间（TOA）；到达频率（FOA）；多源 1

双极化；法布里—珀罗腔天线；与菲涅耳带透镜集成的部分反射面；毫米波波段；高增益；宽带 1

可切换移相器 1

可重构超表面 1

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A Miniature Meta-Optical System for Reconfigurable Wide-Angle Imaging and Polarization-Spectral Detection

Fei Zhang,Minghao Liao,Mingbo Pu,Yinghui Guo,Lianwei Chen,Xiong Li,Qiong He,Tongtong Kang,Xiaoliang Ma,Yuan Ke,Xiangang Luo,

《工程（英文）》 doi: 10.1016/j.eng.2023.07.008

摘要： Wide-angle imaging and spectral detection play vital roles in tasks such as target tracking, object classification, and anti-camouflage. However, limited by their intrinsically different architectures, as determined by frequency dispersion requirements, their simultaneous implementation in a shared-aperture system is difficult. Here, we propose a novel concept to realize reconfigurable dual-mode detection based on electrical-control tunable metasurfaces. As a proof-of-concept demonstration, the simultaneous implementation of wide-angle imaging and polarization-spectral detection in a miniature shared-aperture meta-optical system is realized for the first time via the electrical control of cascaded catenary-like metasurfaces. The proposed system supports the imaging (spectral) resolution of approximately 27.8 line-pairs per millimeter (lp·mm−1; ∼80 nm) for an imaging (spectral) mode from 8 to 14 μm. This system also bears a large field of view of about 70°, enabling multi-target recognition in both modes. This work may promote the miniaturization of multifunctional optical systems, including spectrometers and polarization imagers, and illustrates the potential industrial applications of meta-optics in biomedicine, security, space exploration, and more.

关键词： Metasurfaces     Reconfigurable     Imaging     Spectral    

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Synthesis and properties of polybenzazoles containing flexible methylene in backbone

XU Xiaohui, LIU Xiaoyun, ZHOU Chengjun, ZHUANG Qixin, HAN Zhewen

《化学科学与工程前沿（英文）》 2008年 第2卷 第4期   页码 412-416 doi: 10.1007/s11705-008-0073-5

摘要： A novel series of polybenzazoles with rigid-rod benzoxazole cycle and soft methylene segment was designed and synthesized via solution condensation polymerizations from 4,6-diamino-1,3-benzenediol diphosphate, terephthalic acid and aliphatic dicarboxylic acid. The structures of polybenzazoles were characterized by means of FT-IR, H NMR and Wide-angle X-ray diffraction (WAXRD). All the polymers show excellent thermal stability and the s was above 471°C. The intrinsic viscosities [] of the polymers ranged from 0.8 to 0.9. The UV-Vis absorption peaks of the polymers in MSA were blue-shifted from 429 nm for PBO to 291 nm for PBOC7, and the Stokes shifts in PL spectra enlarged.

关键词： condensation     Wide-angle     absorption     excellent     diffraction    

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用于5G的毫米波宽角扫描天线 Article

Raj Mittra, Abdelkhalek Nasri, Ravi Kumar Arya

《工程（英文）》 2022年 第11卷 第4期   页码 60-73 doi: 10.1016/j.eng.2021.10.017

摘要：

第五代（5G）网络通信系统主要工作在毫米波波段，预计可以提供数千兆的数据速率，这是目前使用无线服务（包括低于6 GHz的频段）所无法实现的。本文简要综述了几种现有的用于5G应用的毫米波相控阵设计。首先，介绍了低剖面天线阵列设计，包括固定波束和仅在一个平面上扫描波束的两种设计类型。随后，介绍了具有二维（2D）扫描能力的阵列系统，该系统对于大多数5G应用而言具有重要意义。接下来，在本文的主体部分，讨论了两种不同的扫描阵列设计策略，这两种策略都规避了用传统移相器来实现波束扫描。值得注意的是，因为在毫米波波段传统的移相器损耗高且价格昂贵，所以找到一个能替代传统移相器的器件是非常必要的；此外，诸如包括射频放大器在内的有源移相器等替代品也是既昂贵又耗电的。在此背景下，本文提出了两种不同的天线系统，这两种天线系统在毫米波范围内具有理想的2D扫描性能。第一种天线系统是龙伯透镜，该透镜由2D波导阵列或微带贴片天线阵列激励，以实现2D扫描能力。第二种天线系统是相控阵设计，该设计采用可切换的PIN二极管或变容二极管取代传统移相器，并将二极管插入波导中的辐射槽之间，从而为扫描提供所需的相移。最后，讨论了几种通过修改传统阵列配置来提高阵列增益的方法。本文还介绍了通过使用可重构的超表面类型的面板来实现一维（1D）和2D扫描的新技术。

关键词： 龙伯透镜     扫描阵列     毫米波天线     可切换移相器     可重构超表面    

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利用碱金属离子效应进行PEDOT:PSS 热电性能工程设计 Article

Jingjin Dong, Jian Liu, Xinkai Qiu, Ryan Chiechi, L. Jan Anton Koster, Giuseppe Portale

《工程（英文）》 2021年 第7卷 第5期   页码 647-654 doi: 10.1016/j.eng.2021.02.011

摘要：

聚（3,4-乙烯二氧噻吩）:聚（苯乙烯磺酸）（PEDOT:PSS）的电学性能设计在传感器、热电（TE）发生器和太阳能电池中的空穴传输层等各种应用方面具有巨大的潜力。应用各种策略可实现PEDOT:PSS的最佳电学性能，如碱性溶液后处理。然而，目前尚不清楚碱性溶液后处理引起的结构转变背后的工作机制和确切细节。在本研究中，我们针对三种常见的绿色碱性溶液，即LiOH、NaOH和KOH的后处理效果提出了一项比较研究，利用原子力显微镜、掠入射广角X射线散射、三波段分光光度计光谱和衰减全反射傅里叶变换红外光谱等技术研究了碱性溶液后处理诱导的薄膜结构改变。碱性溶液诱导的结构改变是造成薄膜热电功率因子提高的原因，这取决于所用的碱性溶液。根据碱金属阳离子和PSS链之间的不同亲和力来解释这一结果，这种亲和力决定了PEDOT不同的去掺杂程度。本文的结果阐明了PEDOT:PSS在暴露于高pH值溶液时发生的结构重组，并可激发未来各种应用领域的pH值/离子响应器件的创新灵感。

关键词： PEDOT:PSS     热电性能     碱性溶液     后处理     结构-性能关系     掠入射广角X射线散射    

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石墨烯超表面宽入射角太赫兹吸收 Research

熊日辉1,彭小青2,李九生1

《信息与电子工程前沿（英文）》 2021年 第22卷 第3期   页码 287-436 doi: 10.1631/FITEE.2000079

摘要： 针对可调宽带宽入射角太赫兹波吸收器，本文提出一种石墨烯超表面结构，该结构在二氧化硅基底上沉积了按平面阵列分布的欧米伽型石墨烯图案。讨论了石墨烯费米能级层和各种基底对吸收特性的影响。在0.82–2.0 THz频率范围内，当入射角为0°–60°时，该太赫兹吸收器的吸收率超过80%。本文研究成果将惠及太赫兹波通信和生物医学成像/传感系统的应用。

关键词： 石墨烯超表面；太赫兹吸收器；欧米伽形石墨烯图案    

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Precise semi-analytical inverse kinematic solution for 7-DOF offset manipulator with arm angle optimization

《机械工程前沿（英文）》 2021年 第16卷 第3期   页码 435-450 doi: 10.1007/s11465-021-0630-x

摘要： Seven-degree-of-freedom redundant manipulators with link offset have many advantages, including obvious geometric significance and suitability for configu-ration control. Their configuration is similar to that of the experimental module manipulator (EMM) in the Chinese Space Station Remote Manipulator System. However, finding the analytical solution of an EMM on the basis of arm angle parameterization is difficult. This study proposes a high-precision, semi-analytical inverse method for EMMs. Firstly, the analytical inverse kinematic solution is established based on joint angle parameterization. Secondly, the analytical inverse kinematic solution for a non-offset spherical–roll–spherical (SRS) redundant manipulator is derived based on arm angle parameterization. The approximate solution of the EMM is calculated in accordance with the relationship between the joint angles of the EMM and the SRS manipulator. Thirdly, the error is corrected using a numerical method through the analytical inverse solution based on joint angle parameterization. After selecting the stride and termination condition, the precise inverse solution is computed for the EMM based on arm angle parameterization. Lastly, case solutions confirm that this method has high precision, and the arm angle parameterization method is superior to the joint angle parameterization method in terms of parameter selection.

关键词： 7-DOF redundant manipulator     inverse kinematics     semi-analytical     arm angle     link offset    

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Evaluating the material strength from fracture angle under uniaxial loading

Jitang FAN

《结构与土木工程前沿（英文）》 2019年 第13卷 第2期   页码 288-293 doi: 10.1007/s11709-018-0480-8

摘要： The most common experimental methods of measuring material strength are the uniaxial compressive and tensile tests. Generally, shearing fracture model occurs in both the tests. Compressive strength is higher than tensile strength for a material. Shearing fracture angle is smaller than 45° under uniaxial compression and greater than 45° under uniaxial tension. In this work, a unified relation of material strength under uniaxial compression and tension is developed by correlating the shearing fracture angle in theory. This constitutive relation is quantitatively illustrated by a function for analyzing the material strength from shear fracture angle. A computational simulation is conducted to validate this theoretical function. It is full of interest to give a scientific illustration for designing the high-strength materials and engineering structures.

关键词： strength     fracture     mechanics    

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Systems understanding of plant–pathogen interactions through genome-wide protein–protein interaction

Hong LI,Ziding ZHANG

《农业科学与工程前沿（英文）》 2016年 第3卷 第2期   页码 102-112 doi: 10.15302/J-FASE-2016100

摘要： Plants are frequently affected by pathogen infections. To effectively defend against such infections, two major modes of innate immunity have evolved in plants; pathogen-associated molecular pattern-triggered immunity and effector-triggered immunity. Although the molecular components as well as the corresponding pathways involved in these two processes have been identified, many aspects of the molecular mechanisms of the plant immune system remain elusive. Recently, the rapid development of omics techniques (e.g., genomics, proteomics and transcriptomics) has provided a great opportunity to explore plant–pathogen interactions from a systems perspective and studies on protein–protein interactions (PPIs) between plants and pathogens have been carried out and characterized at the network level. In this review, we introduce experimental and computational identification methods of PPIs, popular PPI network analysis approaches, and existing bioinformatics resources/tools related to PPIs. Then, we focus on reviewing the progress in genome-wide PPI networks related to plant–pathogen interactions, including pathogen-centric PPI networks, plant-centric PPI networks and interspecies PPI networks between plants and pathogens. We anticipate genome-wide PPI network analysis will provide a clearer understanding of plant–pathogen interactions and will offer some new opportunities for crop protection and improvement.

关键词： plant–pathogen interactions     systems biology     omics     plant immunity     protein–protein interaction     network    

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Advancement in genetic variants conferring obesity susceptibility from genome-wide association studies

null

《医学前沿（英文）》 2015年 第9卷 第2期   页码 146-161 doi: 10.1007/s11684-014-0373-8

摘要：

Obesity prevalence has increased in recent years. Lifestyle change fuels obesity, but genetic factors cause more than 50% of average variations in obesity. The advent of genome-wide association studies (GWAS) has hastened the progress of polygenic obesity research. As of this writing, more than 73 obesity susceptibility loci have been identified in ethnic groups through GWAS. The identified loci explain only 2% to 4% of obesity heritability, thereby indicating that a large proportion of loci remain undiscovered. Thus, the next step is to identify and confirm novel loci, which may exhibit smaller effects and lower allele frequencies than established loci. However, achieving these tasks has been difficult for researchers. GWAS help researchers discover the causal loci. Moreover, numerous biological studies have been performed on the polygenic effects on obesity, such as studies on fat mass- and obesity-associated gene (FTO), but the role of these polygenic effects in the mechanism of obesity remains unclear. Thus, obesity-causing variations should be identified, and insights into the biology of polygenic effects on obesity are needed.

关键词： obesity     genetics     genome-wide association studies     body mass index     fat mass- and obesity-associated gene    

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Genome-wide identification and expression analysis of the β-amylase genes strongly associated with fruit

Hongxia MIAO,Peiguang SUN,Yulu MIAO,Juhua LIU,Jianbin ZHANG,Caihong JIA,Jingyi WANG,Zhuo WANG,Zhiqiang JIN,Biyu XU

《农业科学与工程前沿（英文）》 2016年 第3卷 第4期   页码 346-356 doi: 10.15302/J-FASE-2016127

摘要： β-amylase (BAM) is an important enzyme involved in conversion of starch to maltose in multiple biological processes in plants. However, there is currently insufficient information on the BAM gene family in the important fruit crop banana. This study identified 16 genes in the banana genome. Phylogenetic analysis showed that MaBAMs were classified into four subfamilies. Most in each subfamily shared similar gene structures. Conserved motif analysis showed that all identified MaBAM proteins had the typical glyco hydro 14 domains. Comprehensive transcriptomic analysis of two banana genotypes revealed the expression patterns of in different tissues, at various stages of fruit development and ripening, and in responses to abiotic stresses. Most s showed strong transcript accumulation changes during fruit development and late-stage ripening. Some showed significant changes under cold, salt, and osmotic stresses. This finding indicated that might be involved in regulating fruit development, ripening, and responses to abiotic stress. Analysis of five hormone-related and seven stress-relevant elements in the promoters of further revealed that BAMs participated in various biological processes. This systemic analysis provides new insights into the transcriptional characteristics of the genes in banana and may serve as a basis for further functional studies of such genes.

关键词： β-amylase     banana     genome-wide identification     fruit development     abiotic stress    

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Genome-wide association studies: inherent limitations and future challenges

null

《医学前沿（英文）》 2012年 第6卷 第4期   页码 444-450 doi: 10.1007/s11684-012-0225-3

摘要：

Genome-wide association studies (GWAS) have achieved great success in identifying genetic variants related to complex human diseases such as cancer and have provided valuable insights into their genetic architecture. Recently, GWAS is quite the fashion in China. However, there are issues related to its nature. Enormous work needs to be done in the post-GWAS era. Deep sequencing followed by functional studies will be needed to elucidate the underpinning biological mechanisms and further translate GWAS findings into medical practice. Along with pharmacogenomics, the success of GWAS in identifying genetic risk factors and genetic differences in drug response has been gradually enabling personalized medicine. In this article, we used hepatocellular carcinoma (HCC) as an example to demonstrate some of the inherent limitations and summarized future challenges of GWAS.

关键词： genome-wide association studies (GWAS)     genetic variant     cancer     limitation     challenge    

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Enterprise-wide optimization of integrated planning and scheduling for refinery-petrochemical complex

《化学科学与工程前沿（英文）》 2023年 第17卷 第10期   页码 1516-1532 doi: 10.1007/s11705-022-2283-7

摘要： This paper focuses on the integrated problem of long-term planning and short-term scheduling in a large-scale refinery-petrochemical complex, and considers the overall manufacturing process from the upstream refinery to the downstream petrochemical site. Different time scales are incorporated from the planning and scheduling subproblems. At the end of each discrete time period, additional constraints are imposed to ensure material balance between different time scales. Discrete time representation is applied to the planning subproblem, while continuous time is applied to the scheduling of ethylene cracking and polymerization processes in the petrochemical site. An enterprise-wide mathematical model is formulated through mixed integer nonlinear programming. To solve the problem efficiently, a heuristic algorithm combined with a convolutional neural network (CNN), is proposed. Binary variables are used as the CNN input, leading to the integration of a data-driven approach and classical optimization by which a heuristic algorithm is established. The results do not only illustrate the detailed operations in a refinery and petrochemical complex under planning and scheduling, but also confirm the high efficiency of the proposed algorithm for solving large-scale problems.

关键词： planning     scheduling     refinery-petrochemical     convolutional neural network     heuristic algorithm    

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Genome-wide association study of the backfat thickness trait in two pig populations

Dandan ZHU,Xiaolei LIU,Rothschild MAX,Zhiwu ZHANG,Shuhong ZHAO,Bin FAN

《农业科学与工程前沿（英文）》 2014年 第1卷 第2期   页码 91-95 doi: 10.15302/J-FASE-2014005

摘要： Backfat thickness is a good predictor of carcass lean content, an economically important trait, and a main breeding target in pig improvement. In this study, the candidate genes and genomic regions associated with the tenth rib backfat thickness trait were identified in two independent pig populations, using a genome-wide association study of porcine 60K SNP genotype data applying the compressed mixed linear model (CMLM) statistical method. For each population, 30 most significant single-nucleotide polymorphisms (SNPs) were selected and SNP annotation implemented using Build 10.2. In the first population, 25 significant SNPs were distributed on seven chromosomes, and SNPs on SSC1 and SSC7 showed great significance for fat deposition. The most significant SNP (ALGA0006623) was located on SSC1, upstream of the gene. In the second population, 27 significant SNPs were recognized by annotation, and 12 SNPs on SSC12 were related to fat deposition. Two haplotype blocks, M1GA0016251-MARC0075799 and ALGA0065251-MARC0014203-M1GA0016298-ALGA0065308, were detected in significant regions where the and genes were identified as contributing to fat metabolism. The results indicated that genetic mechanism regulating backfat thickness is complex, and that genome-wide associations can be affected by populations with different genetic backgrounds.

关键词： backfat thickness     SNP chip     genome-wide association study     compressed mixed linear model     pig    

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Computation of the protein molecular mechanism using adaptive dihedral angle increments

Mikel DIEZ, Victor PETUYA, Mónica URIZAR, Erik MACHO, Oscar ALTUZARRRA

《机械工程前沿（英文）》 2013年 第8卷 第1期   页码 104-108 doi: 10.1007/s11465-013-0360-9

摘要：

Protein motion simulation is still a troublesome problem yet to be solved, especially due to its high computational requirements. The procedure presented in this paper makes use of the proteins’ real degrees of freedom (DOFs). The procedure makes no use of any intermediate energy minimization processes that may alter the motion path or result in very high computational cost requirements. In order to reduce the computational cost, presented algorithms make use of the balls and rods approach for protein structure modelization. Also, structures are normalized in order to minimize inaccuracies introduced by experimental methods, providing a more efficient but still accurate structure for motion simulation.

关键词： kinematics     serial robot     proteins     folding     molecular mechanism    

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CFD simulation on shell-and-tube heat exchangers with small-angle helical baffles

Minhua ZHANG,Fang MENG,Zhongfeng GENG

《化学科学与工程前沿（英文）》 2015年 第9卷 第2期   页码 183-193 doi: 10.1007/s11705-015-1510-x

摘要： Shell-and-tube heat exchanger with helical baffles is superior to that with segmental baffles in reducing pressure drop, eliminating dead zone and lowering the risks of vibration of tube bundle. This paper focused on the small-angle helical baffles that have been merely reported in open literature. These baffles are noncontinuous helical baffles with a helix angle of 10° to 30°, and their shapes are 1/4 ellipse, 1/4 sector and 1/3 sector. To assess the integrative performance, /? is employed, and the calculated results show that among the three baffle shapes the heat exchangers with a 1/4 sector helical baffle have the lowest pressure drop. At = 10° and 20°, 1/4 sector helical baffle heat exchangers show the best integrative performance; at = 30°, 1/4 ellipse and 1/4 sector helical baffle heat exchangers perform almost the same. For the study of helix angles, we found that 30° has the best integrative performance at low mass flow rate, almost the same as 20° at high mass flow rate.

关键词： heat transfer     pressure drop     helical baffle     CFD    

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标题 作者 时间 类型 操作

A Miniature Meta-Optical System for Reconfigurable Wide-Angle Imaging and Polarization-Spectral Detection

Fei Zhang,Minghao Liao,Mingbo Pu,Yinghui Guo,Lianwei Chen,Xiong Li,Qiong He,Tongtong Kang,Xiaoliang Ma,Yuan Ke,Xiangang Luo,

期刊论文

Synthesis and properties of polybenzazoles containing flexible methylene in backbone

XU Xiaohui, LIU Xiaoyun, ZHOU Chengjun, ZHUANG Qixin, HAN Zhewen

期刊论文

用于5G的毫米波宽角扫描天线

Raj Mittra, Abdelkhalek Nasri, Ravi Kumar Arya

期刊论文

利用碱金属离子效应进行PEDOT:PSS 热电性能工程设计

Jingjin Dong, Jian Liu, Xinkai Qiu, Ryan Chiechi, L. Jan Anton Koster, Giuseppe Portale

期刊论文

石墨烯超表面宽入射角太赫兹吸收

熊日辉1,彭小青2,李九生1

期刊论文

Precise semi-analytical inverse kinematic solution for 7-DOF offset manipulator with arm angle optimization

期刊论文

Evaluating the material strength from fracture angle under uniaxial loading

Jitang FAN

期刊论文

Systems understanding of plant–pathogen interactions through genome-wide protein–protein interaction

Hong LI,Ziding ZHANG

期刊论文

Advancement in genetic variants conferring obesity susceptibility from genome-wide association studies

null

期刊论文

Genome-wide identification and expression analysis of the β-amylase genes strongly associated with fruit

Hongxia MIAO,Peiguang SUN,Yulu MIAO,Juhua LIU,Jianbin ZHANG,Caihong JIA,Jingyi WANG,Zhuo WANG,Zhiqiang JIN,Biyu XU

期刊论文

Genome-wide association studies: inherent limitations and future challenges

null

期刊论文

Enterprise-wide optimization of integrated planning and scheduling for refinery-petrochemical complex

期刊论文

Genome-wide association study of the backfat thickness trait in two pig populations

Dandan ZHU,Xiaolei LIU,Rothschild MAX,Zhiwu ZHANG,Shuhong ZHAO,Bin FAN

期刊论文

Computation of the protein molecular mechanism using adaptive dihedral angle increments

Mikel DIEZ, Victor PETUYA, Mónica URIZAR, Erik MACHO, Oscar ALTUZARRRA

期刊论文

CFD simulation on shell-and-tube heat exchangers with small-angle helical baffles

Minhua ZHANG,Fang MENG,Zhongfeng GENG

期刊论文