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2021全球十大工程成就 2

光纤通信 2

勘探开发 2

燃煤发电 2

超超临界 2

高含硫 2

(GaxIn1−x)2O3薄膜；带隙可调谐；磁控溅射 1

2型糖尿病 1

5G；交叉振子；双极化天线；终端天线；超宽带 1

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CO2捕集 1

LoRa 1

N-糖基化 1

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PEDOT:PSS 1

Reed-Solomon码；步进式译码算法；超宽带；流水线架构 1

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WiFi多频天线 1

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Relationship between office workers’ staying and workstation attributes in a non-territorial office using ultrawide band sensor network

Xinnan ZHANG, Takashi IZATO, Junzo MUNENOTO, Daisuke MATSUSHITA, Tetsu YOSHIDA

《结构与土木工程前沿（英文）》 2010年 第4卷 第4期   页码 438-449 doi: 10.1007/s11709-010-0076-4

摘要： This paper investigates the staying and moving characteristics of office workers in a non-territorial office using an ultra wide band (UWB) impulse radio sensor network. The differences between office workers’ staying and moving are clarified according to the individual workstation type that they select. The study determines the characteristics of each type of workstation. By clarifying office workers’ preference for staying and moving with regard to individual workstation types and office worker post, the reasons why office workers in different posts tended to select different types of workstations were revealed. Specifically, leaders tended to select workstations at the “inner meeting corner side” most frequently, as they had a greater need to stay in other areas. In contrast, ordinary staff needed to visit office workers in other areas less often, and as such, they tended to select individual workstations at the “middle meeting corner side.” Barring this, they tended to select individual workstations at the “middle corridor side” or “outer-meeting corner side.” Temporary staff members had little need to visit or stay at other places so they tended to select individual workstations at the “window side,” which is seldom visited or stayed at by other office workers and they could be disturbed less often from their solo work.

关键词： workplace     non-territorial office     staying behavior     ultra wide band (UWB)     sensor network    

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Full-band error control and crack-free surface fabrication techniques for ultra-precision fly cutting

F. H. ZHANG, S. F. WANG, C. H. AN, J. WANG, Q. XU

《机械工程前沿（英文）》 2017年 第12卷 第2期   页码 193-202 doi: 10.1007/s11465-017-0448-8

摘要：

Large-aperture potassium dihydrogen phosphate (KDP) crystals are widely used in the laser path of inertial confinement fusion (ICF) systems. The most common method of manufacturing half-meter KDP crystals is ultra-precision fly cutting. When processing KDP crystals by ultra-precision fly cutting, the dynamic characteristics of the fly cutting machine and fluctuations in the fly cutting environment are translated into surface errors at different spatial frequency bands. These machining errors should be suppressed effectively to guarantee that KDP crystals meet the full-band machining accuracy specified in the evaluation index. In this study, the anisotropic machinability of KDP crystals and the causes of typical surface errors in ultra-precision fly cutting of the material are investigated. The structures of the fly cutting machine and existing processing parameters are optimized to improve the machined surface quality. The findings are theoretically and practically important in the development of high-energy laser systems in China.

关键词： ultra-precision fly cutting     large-aperture KDP crystals     spatial frequency     processing error    

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一种改进的用于加载微型航天器小型化超宽带多共振贴片天线的新型H形裂环谐振器超材料 Article

Parul DAWAR, N. S. RAGHAVA, Asok DE

《信息与电子工程前沿（英文）》 2017年 第18卷 第11期   页码 1883-1891 doi: 10.1631/FITEE.1601193

摘要： 本文设计并分析了一种改进H形裂环谐振器（split ring resonator, SRR）的新型超材料。它具有负磁导率和负介电常数特性，且在X，Ku和Ka频带内具有多频共振特性。本文就超材料方向和位置的变化对不同配置下的贴片天线进行了分析。结果表明，新型超材料天线实现了性能优化，表现为9 dB的可观增益，77 GHz的带宽，100%的辐射效率，以及有源区65%的面积缩减。二阶分形超材料天线尺寸降至1/21，从而实现了高度小型化。该研究为急需小尺寸尖波束的通信领域提供了一种解决方案。

关键词： 超宽带；天线；超材料    

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多径环境下脉冲超宽带系统的传输性能分析

林迪,沙学军,吴宣利,张乃通

《中国工程科学》 2009年 第11卷 第2期   页码 75-81

摘要：

为分析多径环境下脉冲超宽带跳时多址系统的传输性能，通过研究IEEE802.4.53a工作组给出的多 径信道参考模型，提出了一个同时存在符号间干扰、符号内多径干扰和多用户干扰的跳时超宽带系统相干解 调的性能分析模型，分别得到了符号内多径干扰、符号间干扰和多用户干扰的方差，且推导得到了系统的误 比特率计算公式，并用计算机仿真验证了公式的有效性。通过计算相邻多径的平均间隔，论证了符号内脉冲 自身多径的干扰是不可忽略的。在不同的信道环境下，以一定误码率要求作为衡量标准，比较了单用户系统 中仅考虑符号间干扰和同时考虑符号内多径干扰及符号间干扰的用户最高传输速率，并分析了多用户系统 中接入不同用户数时对应的平均传输速率的上限。

关键词： 超宽带     符号内多径干扰     符号间干扰     多用户干扰     传输性能分析模型    

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基于广域低功耗网络的能源物联网

宋永华,林今,唐明,董树锋

《工程（英文）》 2017年 第3卷 第4期   页码 460-466 doi: 10.1016/J.ENG.2017.04.011

摘要： 为了突破这一技术难点，本文提出利用通信领域近年来高速发展的广域低功耗网络（low power wide area network, LPWAN）技术，构造全新的能源物联网，从而为能源互联网需求侧的发展带来了全新的技术突破本文介绍以窄带物联网（narrow band internet of things, NB-IoT）和运程（longrange, LoRa）为代表的LPWAN 技术，提出基于该技术实现的能源物联网体系架构

关键词： 能源物联网     广域低功耗网络     NB-IoT     LoRa     需求侧    

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Calculations of narrow-band transimissities and the Planck mean absorption coefficients of real gasesusing line-by-line and statistical narrow-band models

Huaqiang CHU, Mingyan GU, Huaichun ZHOU, Fengshan LIU

《能源前沿（英文）》 2014年 第8卷 第1期   页码 41-48 doi: 10.1007/s11708-013-0292-4

摘要： Narrow-band transmissivities in the spectral range of 150 to 9300 cm and at a uniform resolution of 25 cm were calculated using the statistical narrow-band (SNB) model with the band parameters of Soufiani and Taine, the more recent parameters of André and Vaillon, and the line-by-line (LBL) method along with the HITEMP-2010 spectroscopic database. Calculations of narrow-band transmissivity were conducted for gas columns of different lengths and containing different isothermal and non-isothermal CO -H O-N mixtures at 1 atm. Narrow-band transmissivities calculated by the SNB model are in large relative error at many bands. The more recent SNB model parameters of André and Vaillon are more accurate than the earlier parameters of Soufiani and Taine. The Planck mean absorption coefficients of CO , H O, CO, and CH in the temperature range of 300 to 2500 K were calculated using the LBL method and different versions of the high resolution transmission (HITRAN) and high-temperature spectroscopic absorption parameters (HITEMP) spectroscopic databases. The SNB model was also used to calculate the Planck mean absorption coefficients of these four radiating gases. The LBL results of the Planck mean absorption coefficient were compared with the classical results of Tien and those from the SNB model.

关键词： transimissity     HITEMP     HITRAN     Planck mean absorption coefficients    

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国外光纤光纤带和带状光缆技术的最新发展

刘良炎

《中国工程科学》 2001年 第3卷 第9期   页码 86-94

摘要：

综合介绍了近年国外关于低衰耗的色散补偿光纤，非零色散位移光纤，用于恶劣环境的碳涂覆和氮化硅涂覆光纤的研究；光纤带制造技术包括光纤带的结构、涂层、性能、生产工艺，大芯数光纤带状光缆包括层绞式松管、中心松管式、骨架式、干缆芯带状光缆的设计制造技术的最新进展。

关键词： 光纤通信     低衰耗光纤     光纤带     光纤带状光缆    

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Level set band method: A combination of density-based and level set methods for the topology optimization

Peng WEI, Wenwen WANG, Yang YANG, Michael Yu WANG

《机械工程前沿（英文）》 2020年 第15卷 第3期   页码 390-405 doi: 10.1007/s11465-020-0588-0

摘要： The level set method (LSM), which is transplanted from the computer graphics field, has been successfully introduced into the structural topology optimization field for about two decades, but it still has not been widely applied to practical engineering problems as density-based methods do. One of the reasons is that it acts as a boundary evolution algorithm, which is not as flexible as density-based methods at controlling topology changes. In this study, a level set band method is proposed to overcome this drawback in handling topology changes in the level set framework. This scheme is proposed to improve the continuity of objective and constraint functions by incorporating one parameter, namely, level set band, to seamlessly combine LSM and density-based method to utilize their advantages. The proposed method demonstrates a flexible topology change by applying a certain size of the level set band and can converge to a clear boundary representation methodology. The method is easy to implement for improving existing LSMs and does not require the introduction of penalization or filtering factors that are prone to numerical issues. Several 2D and 3D numerical examples of compliance minimization problems are studied to illustrate the effects of the proposed method.

关键词： level set method     topology optimization     density-based method     level set band    

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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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Fluorene-based narrow-band-gap copolymers for red light-emitting diodes and bulk heterojunction photovoltaic

SUN Mingliang, WANG Li, XIA Yangjun, DU Bin, LIU Ransheng, CAO Yong

《化学科学与工程前沿（英文）》 2008年 第2卷 第3期   页码 257-264 doi: 10.1007/s11705-008-0052-x

摘要： A series of narrow band-gap conjugated copolymers (PFO-DDQ) derived from 9,9-dioctylfluorene (DOF) and 2,3-dimethyl-5,8-dithien-2-yl-quinoxalines (DDQ) is prepared by the palladium-catalyzed Suzuki coupling reaction with the molar feed ratio of DDQ at around 1%, 5%, 15%, 30% and 50%, respectively. The obtained polymers are readily soluble in common organic solvents. The solutions and the thin solid films of the copolymers absorb light from 300–590 nm with two absorbance peaks at around 380 and 490 nm. The intensity of 490 nm peak increases with the increasing DDQ content in the polymers. Efficient energy transfer due to exciton trapping on narrow-band-gap DDQ sites has been observed. The PL emission consists exclusively of DDQ unit emission at around 591–643 nm depending on the DDQ content in solid film. The EL emission peaks are red-shifted from 580 nm for PFO-DDQ1 to 635 nm for PFO-DDQ50. The highest external quantum efficiency achieved with the device configuration ITO/PEDOT/PVK/PFO-DDQ15/Ba/Al is 1.33% with a luminous efficiency 1.54 cd/A. Bulk heterojunction photovoltaic cells fabricated from composite films of PFO-DDQ30 copolymer and [6,6]-phenyl C butyric acid methyl ester (PCBM) as electron donor and electron acceptor, respectively in device configuration: ITO/PEDOT:PSS/PFO-DDQ30:PCBM/PFPNBr/Al shows power conversion efficiencies of 1.18% with open-circuit voltage () of 0.90 V and short-circuit current density () of 2.66 mA/cm under an AM1.5 solar simulator (100 mW/cm). The photocurrent response wavelengths of the PVCs based on PFO-DDQ30/PCBM blends covers 300–700 nm. This indicates that these kinds of low band-gap polymers are promising candidates for polymeric solar cells and red light-emitting diodes.

关键词： simulator     Efficient     band-gap     PFO-DDQ50     intensity    

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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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Controlling nested wrinkle morphology through the boundary effect on narrow-band thin films

Hanyang XU, Tielin SHI, Guanglan LIAO, Qi XIA

《机械工程前沿（英文）》 2019年 第14卷 第2期   页码 235-240 doi: 10.1007/s11465-017-0458-6

摘要： We describe the formation of nested wrinkles created by the thermal mismatch between a narrow-band thin film and a compliant substrate. When a film is described as “narrow-band”, it literally means that the film band width is much shorter than its length; more precisely, it means that the width is comparable with the wavelength of the wrinkles. A silicon mask was used during film sputtering to create narrow-band films on poly (dimethylsiloxane) substrate, thus creating regular boundaries to steer local stresses and control wrinkle morphology. Disordered nano-scale wrinkles were found nested within highly ordered micro-scale sinusoidal wrinkles. The formation of nested wrinkles was explained through the amplitude and wavelength saturation of nano-scale wrinkles. The disordered morphology of nano-scale wrinkles and the highly ordered morphology of micro-scale wrinkles were explained by using the boundary effect.

关键词： nested and hierarchical wrinkles     morphology     amplitude saturation     boundary effect    

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Existence of complete band gaps in 2D steel-water phononic crystal with square lattice

Cunfu HE, Huanyu ZHAO, Ruiju WEI, Bin WU

《机械工程前沿（英文）》 2010年 第5卷 第4期   页码 450-454 doi: 10.1007/s11465-010-0105-y

摘要： This paper theoretically and experimentally studies the existence of complete band gaps in two-dimensional (2D) phononic crystal consisting of parallel steel rods in water with square lattice. The band structure of phononic crystal is calculated by a plane wave expansion (PWE) method. Based on the well-known ultrasonic immersion transmission technique, the overlapping transmission spectra of acoustic waves, a complete band gap, is experimentally measured along the two high-symmetry directions of the first irreducible Brillouin zone. There is a very good agreement between the experimental result and the range of frequencies of the complete band gap.

关键词： phononic crystal     plane wave expansion (PWE) method     experimental study    

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Review on the progress of ultra-precision machining technologies

Julong YUAN, Binghai LYU, Wei HANG, Qianfa DENG

《机械工程前沿（英文）》 2017年 第12卷 第2期   页码 158-180 doi: 10.1007/s11465-017-0455-9

摘要：

Ultra-precision machining technologies are the essential methods, to obtain the highest form accuracy and surface quality. As more research findings are published, such technologies now involve complicated systems engineering and been widely used in the production of components in various aerospace, national defense, optics, mechanics, electronics, and other high-tech applications. The conception, applications and history of ultra-precision machining are introduced in this article, and the developments of ultra-precision machining technologies, especially ultra-precision grinding, ultra-precision cutting and polishing are also reviewed. The current state and problems of this field in China are analyzed. Finally, the development trends of this field and the coping strategies employed in China to keep up with the trends are discussed.

关键词： ultra-precision grinding     ultra-precision cutting     ultra-precision polishing     research status in China     development tendency    

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标题 作者 时间 类型 操作

Relationship between office workers’ staying and workstation attributes in a non-territorial office using ultrawide band sensor network

Xinnan ZHANG, Takashi IZATO, Junzo MUNENOTO, Daisuke MATSUSHITA, Tetsu YOSHIDA

期刊论文

Full-band error control and crack-free surface fabrication techniques for ultra-precision fly cutting

F. H. ZHANG, S. F. WANG, C. H. AN, J. WANG, Q. XU

期刊论文

一种改进的用于加载微型航天器小型化超宽带多共振贴片天线的新型H形裂环谐振器超材料

Parul DAWAR, N. S. RAGHAVA, Asok DE

期刊论文

多径环境下脉冲超宽带系统的传输性能分析

林迪,沙学军,吴宣利,张乃通

期刊论文

基于广域低功耗网络的能源物联网

宋永华,林今,唐明,董树锋

期刊论文

Calculations of narrow-band transimissities and the Planck mean absorption coefficients of real gasesusing line-by-line and statistical narrow-band models

Huaqiang CHU, Mingyan GU, Huaichun ZHOU, Fengshan LIU

期刊论文

国外光纤光纤带和带状光缆技术的最新发展

刘良炎

期刊论文

Level set band method: A combination of density-based and level set methods for the topology optimization

Peng WEI, Wenwen WANG, Yang YANG, Michael Yu WANG

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

Fluorene-based narrow-band-gap copolymers for red light-emitting diodes and bulk heterojunction photovoltaic

SUN Mingliang, WANG Li, XIA Yangjun, DU Bin, LIU Ransheng, CAO Yong

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

Controlling nested wrinkle morphology through the boundary effect on narrow-band thin films

Hanyang XU, Tielin SHI, Guanglan LIAO, Qi XIA

期刊论文

Existence of complete band gaps in 2D steel-water phononic crystal with square lattice

Cunfu HE, Huanyu ZHAO, Ruiju WEI, Bin WU

期刊论文

Review on the progress of ultra-precision machining technologies

Julong YUAN, Binghai LYU, Wei HANG, Qianfa DENG

期刊论文