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优化 2

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CP）；符号间干扰（inter symbol interference， ISI）；载波间干扰（inter carrier interference 1

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Non-invasive continuous blood pressure monitoring: a review of current applications

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《医学前沿（英文）》 2013年第7卷第1期页码 91-101 doi: 10.1007/s11684-013-0239-5

摘要：

Blood pressure monitoring has come a long way from the initial observations made by Reverend Hales in the 18th century. There are none that deny the importance of monitoring perioperative blood pressure; however, the limited ability of the current prevalent technology (oscillometric blood pressure monitoring) to offer continuous blood pressure measurements leaves room for improvement. Invasive monitoring is able to detect beat-to-beat blood pressure measurement, but the risks inherent to the procedure make it unsuitable for routine use except when this risk is outweighed by the benefits. This review focuses on the discoveries which have led up to the current blood pressure monitoring technologies, and especially the creation of those offering non-invasive but continuous blood pressure monitoring capabilities, including their methods of measurement and limitations.

关键词： non-invasive blood pressure monitoring continuous blood pressure monitoring invasive blood pressure monitoring Riva-Rocci technique oscillometric Pe?áz technique arterial tonometry pulse transit time

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General modeling and optimization technique for real-world earth observation satellite scheduling

《工程管理前沿（英文）》 2023年第10卷第4期页码 695-709 doi: 10.1007/s42524-023-0263-3

摘要： Over the last two decades, many modeling and optimization techniques have been developed for earth observation satellite (EOS) scheduling problems, but few of them show good generality to be engineered in real-world applications. This study proposes a general modeling and optimization technique for common and real-world EOS scheduling cases; it includes a decoupled framework, a general modeling method, and an easy-to-use algorithm library. In this technique, a framework that decouples the modeling, constraints, and optimization of EOS scheduling problems is built. With this framework, the EOS scheduling problems are appropriately modeled in a general manner, where the executable opportunity, another format of the well-known visible time window per EOS operation, is viewed as a selectable resource to be optimized. On this basis, 10 types of optimization algorithms, such as Tabu search and genetic algorithm, and a parallel competitive memetic algorithm, are developed. For simplified EOS scheduling problems, the proposed technique shows better performance in applicability and effectiveness than the state-of-the-art algorithms. In addition, a complicatedly constrained real-world benchmark exampled by a four-EOS Chinese commercial constellation is provided, and the technique is qualified and outperforms the in-use scheduling system by more than 50%.

关键词： earth observation satellite scheduling general technique optimization algorithm commercial constellation real-world benchmark

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构建我国农业信息化技术支持体系的探讨

郭书普,张立平,沈基长,董伟

《中国工程科学》 2005年第7卷第9期页码 89-94

摘要：

阐述了农业信息化的基本特征，介绍了农业信息化技术支持体系的发展现状，分析了存在的问题，指出现阶段加快农业信息技术体系建设应当重点抓好农业信息贮藏技术的研究、农业信息应用技术的开发、农业信息传播网络的建设。

关键词：农业信息化技术支持体系信息贮藏技术信息应用技术信息传播网络

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Diversity-oriented synthesis of blue emissive nitrogen heterocycles and their conjugation with carbon nano-onions

Viviana Maffeis, Lisa Moni, Daniele Di Stefano, Silvia Giordani, Renata Riva

《化学科学与工程前沿（英文）》 2020年第14卷第1期页码 76-89 doi: 10.1007/s11705-019-1833-0

摘要： The search for new fluorescent molecules for possible applications as functional -electron systems and their conjugation with different nanomaterials is nowadays of paramount importance to broaden the availability of materials with different properties. Herein we present a diversity-oriented approach to heterocyclic luminophores based on a multicomponent Ugi reaction followed by a Pd-mediated cascade sequence. The new molecules are coupled to carbon nano-onions, and hybrid systems represent the first example of blue emitters conjugated with these carbon nanoparticles.

关键词： carbon nano-onions multicomponent reactions blue emitters fluorescence isoquinolines

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The electrostatic-alloy bonding technique used in MEMS

WANG Wei, CHEN Wei-ping

《机械工程前沿（英文）》 2006年第1卷第2期页码 238-241 doi: 10.1007/s11465-006-0011-5

摘要： Electrostatic-alloy bonding of silicon wafer with glass deposited by Au to form Si/Au-glass water, and bonding of Si/Au-glass with silicon wafer were researched during fabrication of pressure sensors. The silicon wafer and glass wafer with an Au film resistor were bonded by electrostatic bonding, and then Si-Au alloy bonding was formed by annealing at 400vH for 2 h. The air sealability of the cavity after bonding was finally tested using the N filling method. The results indicate that large bond strength was obtained at the bonding interface. This process was used in fabricating a pressure sensor with a sandwich structure. The results indicate that the sensor presented better performances and that the bonding techniques can be used in MEMS packaging.

关键词： Si/Au-glass strength MEMS packaging process sandwich structure

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Seismic safety evaluation methodology for masonry building and retrofitting using splint and bandage technique

Pravin Kumar Venkat Rao PADALU; Yogendra SINGH

《结构与土木工程前沿（英文）》 2022年第16卷第4期页码 478-505 doi: 10.1007/s11709-022-0817-1

摘要： The paper presents a seismic safety assessment of unreinforced masonry (URM) building using two approaches. The first approach uses the ‘Pier Analysis’ method, based on the concept of equivalent lateral stiffness, where in-plane and out-of-plane actions are considered independently. The second approach is developed with the program SAP2000, where the linear response is evaluated using continuum ‘finite element modelling’ (FEM). Both methods are compared to evaluate the safety of wall piers and the differences in the outcomes under combined gravitational and lateral seismic forces. The analysis results showed that few wall elements are unsafe in in-plane and out-of-plane tension. It is also observed that the pier analysis method is conservative compared to FEM, but can be used as a simplified and quick tool in design offices for safety assessment, with reasonable accuracy. To safeguard the URM wall piers under lateral loads, a retrofitting technique is adopted by providing vertical and horizontal belts called splints and bandages, respectively, using welded wire mesh (WWM) reinforcement. The study using the ‘Pier Analysis’ shows that the lateral load capacity of unsafe URM piers can be enhanced up to 3.67 times and made safe using the applied retrofitting technique. Further, the retrofitting design methodology and recommendations for application procedures to on-site URM buildings are discussed in detail.

关键词： unreinforced masonry seismic in-plane and out-of-plane forces pier analysis finite element modelling splint and bandage technique with wire mesh

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Significance of using isolated footing technique for residential construction on expansive soils

Harry FAR,Deacon FLINT

《结构与土木工程前沿（英文）》 2017年第11卷第1期页码 123-129 doi: 10.1007/s11709-016-0372-8

摘要： Expansive soils cause problems with the founding of lightly loaded structures in many parts of the world. Foundation design for expansive soils is one of the most discussed and problematic issues in Australia as expansive soils were responsible for billions of dollars’ worth of damage to man-made structures such as buildings and roads. Several studies and reports indicate that one of the most common and least recognized problems causing severe structural damage to houses lies in expansive soils. In this study, a critical review has been carried out on the current Australian standards for building on expansive soils and they are compared with some techniques that are not included in the current Australian standards for residential slabs and footings. Based on the results of this review, the most effective and economical method has been proposed for construction of footings on all site classifications without restriction to 75mm of characteristic movement. In addition, it has become apparent that as design procedures for footings resting on sites with extreme characteristic movements are not included in the current Australian standards, there is a strong need for well-developed and simplified standard design procedures for characteristic soil movement of greater than 75mm to be included into the Australian Standards.

关键词： expansive soils residential slabs isolated footings Australian Standards

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Knife-edge technique for laser cooling

WANG Zhanshan, MA Shanshan, MA Yan, ZHAO Min, LIU Hengbiao

《机械工程前沿（英文）》 2007年第2卷第4期页码 468-473 doi: 10.1007/s11465-007-0081-z

摘要： The transfer characteristics of an atomic beam and the effect of laser were investigated in this paper. In the application of knife-edge technique, the temperature of atoms through laser cooling was measured. Results indicate that, after atoms are emitted from an atomic oven, the longer the atoms move, the worse the distribution of the atomic beam shows, regardless the laser cooling is taken or not. Laser cooling can reduce the transverse velocity of the atomic beam to several orders of magnitude and also increase the uniformity of an atomic beam. Knife-edge technique can measure the temperature of an atomic beam through laser cooling. The measurement accuracy depends on the pixel size of the charge coupled device (CCD), which is used for the fluorescent imaging of the atomic beam. The results are very important for the future experiments of laser cooling.

关键词： knife-edge technique uniformity coupled transfer fluorescent

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国外水电技术的发展

陈宗梁

《中国工程科学》 2002年第4卷第4期页码 86-92

摘要：

概述了国外水电建设中的技术发展情况，着重论述了物探、高坝和抗震、厂房优化布置、洞内消能、预应力混凝土衬砌隧洞、大坝监测和老坝检测修复等几项重大技术在水电工程中的应用。

关键词：水电国外新技术发展

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生物技术在养羊业科学研究中的应用

刘守仁

《中国工程科学》 2001年第3卷第7期页码 37-41

摘要：

介绍了冷冻精液、胚胎移植、胚胎冷冻、胚胎分割、体外受精、核移植克隆、基因导入等技术。这些技术的应用使养羊业育种和生产水平大为提高，产生了显著的经济效益。同时，为养羊业科研和生产开辟了新的途径。

关键词：生物技术养羊业

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New technique of precision necking for long tubes with variable wall thickness

Yongqiang GUO, Chunguo XU, Jingtao HAN, Zhengyu WANG

《机械工程前沿（英文）》 2020年第15卷第4期页码 622-630 doi: 10.1007/s11465-019-0565-7

摘要： This study analyzed the deformation law of rear axles with variable wall thickness under bidirectional horizontal extrusion and found that necking was accompanied by upsetting deformation through theoretical calculation, numerical simulation, and experimental research. The sequence and occurrence of necking and upsetting deformations were obtained. A theory of deformation was proposed by controlling the distribution of temperature field. Effective processes to control the wall thickness of rear axle at different positions were also proposed. The ultimate limit deformation with a necking coefficient of 0.68 could be achieved using the temperature gradient coefficient. A new technology of two-step heating and two-step extrusion for a 13 t rear axle was developed, qualified test samples were obtained, and suggestions for further industrial application were put forward.

关键词： extrusion rear axle necking coefficient temperature gradient

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Manufacturing technique and performance of functionally graded concrete segment in shield tunnel

Baoguo MA, Dinghua ZOU, Li XU

《结构与土木工程前沿（英文）》 2009年第3卷第1期页码 101-104 doi: 10.1007/s11709-009-0011-8

摘要： The quality of segment is very important to the service life of shield tunnel. Concerning the complex engineering environment of the Wuhan Yangtze River Shield Tunnel, the principle of functionally graded materials was introduced to design and produce the functionally graded concrete segment (FGCS). Its key manufacturing technique was proposed and its performance was tested.

关键词： shield tunnel functionally graded concrete segment (FGCS) manufacturing technology performance

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Study of operation optimization based on data mining technique in power plants

LI Jianqiang, LIU Jizhen, GU Junjie, NIU Chenglin

《能源前沿（英文）》 2007年第1卷第4期页码 457-462 doi: 10.1007/s11708-007-0067-1

摘要： The determination of operation optimization value is very important for economic analysis and operation optimization in power plants. The operation optimization value determined by traditional methods usually cannot reflect the ac

关键词： traditional optimization determination economic analysis important

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Digital microfluidics: A promising technique for biochemical applications

He WANG, Liguo CHEN, Lining SUN

《机械工程前沿（英文）》 2017年第12卷第4期页码 510-525 doi: 10.1007/s11465-017-0460-z

摘要：

Digital microfluidics (DMF) is a versatile microfluidics technology that has significant application potential in the areas of automation and miniaturization. In DMF, discrete droplets containing samples and reagents are controlled to implement a series of operations via electrowetting-on-dielectric. This process works by applying electrical potentials to an array of electrodes coated with a hydrophobic dielectric layer. Unlike microchannels, DMF facilitates precise control over multiple reaction processes without using complex pump, microvalve, and tubing networks. DMF also presents other distinct features, such as portability, less sample consumption, shorter chemical reaction time, flexibility, and easier combination with other technology types. Due to its unique advantages, DMF has been applied to a broad range of fields (e.g., chemistry, biology, medicine, and environment). This study reviews the basic principles of droplet actuation, configuration design, and fabrication of the DMF device, as well as discusses the latest progress in DMF from the biochemistry perspective.

关键词： digital microfluidics electrowetting on dielectric discrete droplet biochemistry

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An efficient technique for improving methanol yield using dual CO

Yang Su, Liping Lü, Weifeng Shen, Shun’an Wei

《化学科学与工程前沿（英文）》 2020年第14卷第4期页码 614-628 doi: 10.1007/s11705-019-1849-5

摘要： Abstract Steam methane reforming (SMR)-based methanol synthesis plants utilizing a single CO2 feed represent one of the predominant technologies for improving methanol yield and CO2 utilization. However, SMR alone cannot achieve full CO2 utilization, and a high water content accumulates if CO2 is only fed into the methanol reactor. In this study, a process integrating SMR with dry methane reforming to improve the conversion of both methane and CO2 is proposed. We also propose an innovative methanol production approach in which captured CO2 is introduced into both the SMR process and the recycle gas of the methanol synthesis loop. This dual CO2 feed approach aims to optimize the stoichiometric ratio of the reactants. Comparative evaluations are carried out from a techno-economic point of view, and the proposed process is demonstrated to be more efficient in terms of both methanol productivity and CO2 utilization than the existing stand-alone natural gas-based methanol process.

关键词： methanol synthesis CO₂ utilization dry methane reforming steam methane reforming process design