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Nanotechnology in Nuclear Reactors: Innovations in Fusion and Fission Power Generation
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作者 Bahman Zohuri 《Journal of Energy and Power Engineering》 CAS 2024年第2期71-74,共4页
This article explores the transformative potential of nanotechnology and MMs(memory metals)in enhancing the design and operation of nuclear reactors,encompassing both fission and fusion technologies.Nanotechnology,wit... This article explores the transformative potential of nanotechnology and MMs(memory metals)in enhancing the design and operation of nuclear reactors,encompassing both fission and fusion technologies.Nanotechnology,with its ability to engineer materials at the atomic scale,offers significant improvements in reactor safety,efficiency,and longevity.In fission reactors,nanomaterials enhance fuel rod integrity,optimize thermal management,and improve in-core instrumentation.Fusion reactors benefit from nanostructured materials that bolster containment and heat dissipation,addressing critical challenges in sustaining fusion reactions.The integration of SMAs(shape memory alloys),or MMs,further amplifies these advancements.These materials,characterized by their ability to revert to a pre-defined shape under thermal conditions,provide self-healing capabilities,adaptive structural components,and enhanced magnetic confinement.The synergy between nanotechnology and MMs represents a paradigm shift in nuclear reactor technology,promising a future of cleaner,more efficient,and safer nuclear energy production.This innovative approach positions the nuclear industry to meet the growing global energy demand while addressing environmental and safety concerns. 展开更多
关键词 NANOTECHNOLOGY MMS fission reactors fusion reactors SMAS nuclear energy reactor safety thermal management structural integrity advanced materials
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Progress and Achievements of Multi-sensor Fusion Navigation in China during 2019—2023
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作者 Xingxing LI Xiaohong ZHANG +12 位作者 Xiaoji NIU Jian WANG Ling PEI Fangwen YU Hongjuan ZHANG Cheng YANG Zhouzheng GAO Quan ZHANG Feng ZHU Weisong WEN Tuan LI Jianchi LIAO Xin LI 《Journal of Geodesy and Geoinformation Science》 CSCD 2023年第3期102-114,共13页
Global Navigation Satellite System(GNSS)can provide all-weather,all-time,high-precision positioning,navigation and timing services,which plays an important role in national security,national economy,public life and ot... Global Navigation Satellite System(GNSS)can provide all-weather,all-time,high-precision positioning,navigation and timing services,which plays an important role in national security,national economy,public life and other aspects.However,in environments with limited satellite signals such as urban canyons,tunnels,and indoor spaces,it is difficult to provide accurate and reliable positioning services only by satellite navigation.Multi-source sensor integrated navigation can effectively overcome the limitations of single-sensor navigation through the fusion of different types of sensor data such as Inertial Measurement Unit(IMU),vision sensor,and LiDAR,and provide more accurate,stable and robust navigation information in complex environments.We summarizes the research status of multi-source sensor integrated navigation technology,and focuses on the representative innovations and applications of integrated navigation and positioning technology by major domestic scientific research institutions in China during 2019—2023. 展开更多
关键词 Simultaneous Localization and Mapping(SLAM) integrated navigation multi-sensor fusion
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Innovative integrating of hot-dipped(aluminizing) galvanizing lines and engineering of related equipment
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作者 CHENG Liangjian,DU Jun,HOU Ligang,ZHUANG Guowei, WANG Fukai,WEI Wei and LU Zhiyi Baosteel Engineering & Technology Group Co.,Ltd.,Shanghai 201900,China 《Baosteel Technical Research》 CAS 2010年第S1期115-,共1页
Based on the continuous hot(aluminizing) galvanizing lines and related non-standard equipment of Meishan Steel,this paper presents the main contents of such integrated engineering and designing of equipment for the tw... Based on the continuous hot(aluminizing) galvanizing lines and related non-standard equipment of Meishan Steel,this paper presents the main contents of such integrated engineering and designing of equipment for the two hot-dipped galvanizing lines,as well as innovative techniques and their features.Led by Cold Rolling Project Department of Meishan Steel,Baosteel Engineering and Technology Group Co.,Ltd. ,working as the responsible unit of this project,develops key technologies and integrates the system by combining the equipment design and development capacity of Baosteel Engineering,research and development capacity of Research Institute of Baosteel,process production and equipment maintenance experience of Cold Rolling Plant,Equipment Department and Manufacture Department of Baosteel Corporation.Core technologies of the two lines are developed and designed through original and integrated innovation and innovation after digestion,focusing on eight core techniques in process equipment,annealing furnace,fluid installation and EIC system.As a result of integration in key process equipment,industrial furnace and EIC control,the cold rolling hot dipped(aluminizing) galvanizing lines take on a new look and reach an annual capacity of 200 000 t galvanized products and 250 000 t galvanized aluminium base strips respectively.These two world advanced lines are able to produce hot-dipped galvanizing products with high quality surface and fine shape,such as household appliance board and senior construction board.As a result, the process and equipment technology of the lines have formed domestic intellectual property.Thus,the technology has reference value for self-integration and equipment technology innovation of similar lines. 展开更多
关键词 hot galvanizing lines project innovative integration research on equipment inNOVATION
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KIRCHHOFF FORMULA WITH LINE INTEGRAL FORM AND ITS APPLICATIONS
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作者 顾长青 徐金平 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1999年第2期183-187,共5页
In this paper, Kirchhoff formula has been transformed from surface integral form into a line integral form. The new form of the formula can be applied to separate geometrical optical field from diffraction field, and ... In this paper, Kirchhoff formula has been transformed from surface integral form into a line integral form. The new form of the formula can be applied to separate geometrical optical field from diffraction field, and reduce the time of numerical computation greatly. Based on the new form, an analytical formula of diffraction field in the far zone has been presented for the polygonal aperture illuminated by a uniform plane wave. 展开更多
关键词 wave propagation DIFFRACTION integrals of Cauchy type Kirchhoff formula line integral
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Application of the cortical bone trajectory technique in posterior lumbar fixation 被引量:2
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作者 Shi-Bo Peng Xi-Chuan Yuan +1 位作者 Wei-Zhong Lu Ke-Xiao Yu 《World Journal of Clinical Cases》 SCIE 2023年第2期255-267,共13页
The cortical bone trajectory(CBT) is a novel technique in lumbar fixation and fusion.The unique caudocephalad and medial-lateral screw trajectories endow it with excellent screw purchase for vertebral fixation via a m... The cortical bone trajectory(CBT) is a novel technique in lumbar fixation and fusion.The unique caudocephalad and medial-lateral screw trajectories endow it with excellent screw purchase for vertebral fixation via a minimally invasive method.The combined use of CBT screws with transforaminal or posterior lumbar interbody fusion can treat a variety of lumbar diseases,including spondylolisthesis or stenosis,and can also be used as a remedy for revision surgery when the pedicle screw fails.CBT has obvious advantages in terms of surgical trauma,postoperative recovery,prevention and treatment of adjacent vertebral disease,and the surgical treatment of obese and osteoporosis patients.However,the concept of CBT internal fixation technology appeared relatively recently;consequently,there are few relevant clinical studies,and the long-term clinical efficacy and related complications have not been reported.Therefore,large sample and prospective studies are needed to further reveal the long-term complications and fusion rate.As a supplement to the traditional pedicle trajectory fixation technique,the CBT technique is a good choice for the treatment of lumbar diseases with accurate screw placement and strict indications and is thus deserving of clinical recommendation. 展开更多
关键词 Cortical bone trajectory Management of midle line fusion Lumbar interbody fusion Lumbar surgery REVIEW
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Effect of cell fusion on metastatic ability of mouse hepatocarcinoma cell lines 被引量:12
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作者 JI Yan 1, LING Mao Ying 1, LI Ying 1 and XIE Hong 2 《World Journal of Gastroenterology》 SCIE CAS CSCD 1999年第1期27-29,共3页
AIM To study the effect of cell fusion on metastatic ability of mouse hepatocarcinoma cells and the factors involved in the process of metastasis. METHODS By the method of successively increasing the concentrations... AIM To study the effect of cell fusion on metastatic ability of mouse hepatocarcinoma cells and the factors involved in the process of metastasis. METHODS By the method of successively increasing the concentrations, cell fusion and limit dilution, 8 Ag resistant cells were selected, and HGPRT - Hca P cells and eight cloned hybridoma cells were obtained. To observe their metastatic ability, they were inoculated into mice foodtaps and the drainage lymph nodes were examined under microscope. RESULTS The end concentration of 8 Ag which was used to select HGPRT deficient Hca P cells was 30mg/L . All the cells selected died in HAT culture medium in one week. Fused cells appeared approximately 9 days later. They were round, transparent and a little larger than their parental cells. Eight clones of hybridoma cells were obtained and named as PSH1 PSH8. The metastatic rate of HGPRT - Hca P cells and PSH7 cells was 28 6% and 71 4% respectively, the difference being significant ( P <0 05). The metastatic rate of other clones was no more than 20% and there was no significant difference from HGPRT - Hca P cells ( P >0 05). CONCLUSION In normal mice splenic lymphocytes, there are some factors that could inhibit tumor metastasis, however, there are some other factors accelerating tumor cells to metastasize. The establishment of PSH7 provides an experimental model which could be used to study the factors involved in metastasis. 展开更多
关键词 carcinoma hepatocellular CELL lineS CELL fusion neoplasm METASTASIS LYMPHATIC METASTASIS
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Linkage analysis and integrated software GAPL for pure-line populations derived from four-way and eight-way crosses 被引量:6
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作者 Luyan Zhang Lei Meng Jiankang Wang 《The Crop Journal》 SCIE CAS CSCD 2019年第3期283-293,共11页
Pure lines derived from multiple parents provide abundant variation for genetic study.However,efficient genetic analysis methods and user-friendly software are still lacking.In this study, we developed linkage analysi... Pure lines derived from multiple parents provide abundant variation for genetic study.However,efficient genetic analysis methods and user-friendly software are still lacking.In this study, we developed linkage analysis methods and integrated analysis software for pure-line populations derived from four-way and eight-way crosses.First, polymorphic markers are classified into different categories according to the number of identifiable alleles in the inbred parents.Expected genotypic probability is then derived for each pair of complete markers, and based on them a maximum likelihood estimate(MLE) of recombination frequency is calculated.An EM algorithm is proposed for calculating recombination frequencies in scenarios that at least one marker is incomplete.A linkage map can thus be constructed using estimated recombination frequencies.We describe a software package called GAPL for recombination frequency estimation and linkage map construction in multi-parental pure-line populations.Both simulation studies and results from a reported four-way cross recombinant inbred line population demonstrate that the proposed method and software can build more accurate linkage maps in shorter times than other published software packages.The GAPL software is freely available from www.isbreeding.net and can also be used for QTL mapping in multi-parental populations. 展开更多
关键词 Pure lines Four-way CROSS Eight-way CROSS Recombination frequency estimation integrated software
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Alternatingly stacked thin film electrodes-based compact aqueous hybrid electrochemical capacitors for hundred-volts AC line filtering
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作者 Lixia Wang Lingyu Zhao +8 位作者 Meirong Song Lixia Xie Xiaopeng Wang Xin Li Yanjie Huang Min Wei Qiu Jin Xianglong Meng Yang Zhao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第3期158-168,I0005,共12页
Filtering capacitor with compact configuration and a wide range of operating voltage has been attracting increasing attention for the smooth conversion of the electric signal in modern circuits.Lossless integration of... Filtering capacitor with compact configuration and a wide range of operating voltage has been attracting increasing attention for the smooth conversion of the electric signal in modern circuits.Lossless integration of capacitor units can be regarded as one of the efficient ways to achieve a wider voltage range,which has not yet been fully conquered due to the lack of rational designs of the electrode structure and integration technology.This study presents an alternatingly stacked assemble technology to conveniently fabricate compact aqueous hybrid integrated filtering capacitors on a large scale,in which a unit consists of rGO/MXene composite film as a negative electrode and PEDOT:PSS based film as a positive electrode.Benefiting from the synergistic effect of rGO and MXene components,and morphological characteristics of PEDOT:PSS,the capacitor unit exhibits outstanding AC line filtering with a large areal specific energy density of 1,015 μF V^(2)cm^(-2)(0.28 μW h cm^(-2)) at 120 Hz.After rational integration,the assembled capacitors present compact/lightweight configuration and lossless frequency response,as reflected by almost constant resistor-capacitor time constant of 0.2 ms and dissipation factor of 15% at120 Hz,identical to those of the single capacitor unit.Apart from standing alone steadily on a flower,a small volume(only 8.1 cm^(3)) of the integrated capacitor with 70 units connected in series achieves hundred-volts alternating current line filtering,which is superior to most reported filtering capacitors with sandwich configuration.This study provides insight into the fabrication and application of compact/ultralight filtering capacitors with lossless frequency response,and a wide range of operating voltage. 展开更多
关键词 Alternatingly stacked assembly Lossless integration Aqueous hybrid electrochemical capacitor Synergistic effect Morphological characteristics COMPACT Hundred-volts AC linefiltering
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Knowledge Fusion and Synchronization over Ubiquitous Ontology Mapping 被引量:1
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作者 Hang Qin Li Zhu 《Journal of Computer and Communications》 2017年第10期1-9,共9页
With the rapid development and popularization of web services, the available information types and structure are becoming more and more complex and challenging. Actually web services involve the need for dynamic integ... With the rapid development and popularization of web services, the available information types and structure are becoming more and more complex and challenging. Actually web services involve the need for dynamic integration and transparent knowledge integration, in light of the urgent information changing track. Under this situation, the traditional search engine and information integration cannot finish this challenge, thereby bringing the opportunity for knowledge fusion and synchronization. This paper proposes a multi-matching strategy ontology mapping method for web information, i.e., ubiquitous ontology mapping method (U-Mapping), which can be viewed as a base collection of information on multiple ontologies made to appear anytime and everywhere. This approach is usually built independently by different information providers, avoiding the grammatical and semantic conflict. Finally, the ontology case information can be utilized under the consolidation of the U-Mapping, concerning language technology and machine learning methods. 展开更多
关键词 UBIQUITOUS Ontology Mapping KNOWLEDGE fusion information integration KNOWLEDGE SYNCHRONIZATION CONCEPTUAL Space fusion RULES
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System integration and innovation of operating 20 kt combined heavy-haul train on Datong-Qinhuangdao line 被引量:2
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作者 Geng Zhixiu 《Engineering Sciences》 EI 2008年第3期12-26,共15页
Datong-Qinhuangdao line, as the first electrified double-track heavy-haul line dedicated to coal transport in China, extends from Datong in the west, and reaches Qinhuangdao in the east, opened to traffic in December,... Datong-Qinhuangdao line, as the first electrified double-track heavy-haul line dedicated to coal transport in China, extends from Datong in the west, and reaches Qinhuangdao in the east, opened to traffic in December, 1992, totaling 653 km with the designed annual traffic volume of 1×108 t. In order to meet the demands of national economic development, the transport capacity of the line must be enhanced greatly. Depending on independent innovation, MOR, for the first time in the world,realizes the integration between GSM-R and Locotrol, the integration between 800 MHz digital radio and Locotrol, and the integration between a single set of Locotrol and SS4 locomotive. Meanwhile, CR develops equipment portfolio for heavy-haul through combining 2 high power locomotives of HXD series (means harmony) with controllable EOT. Relying on integration and innovation, it succeeds in operating 20 kt-level combined heavy-haul train on Datong-Qinhuangdao line, which tripled the annual traffic volume of the line from 1×108 t in 2002 to 3×108 t in 2007. 展开更多
关键词 China railways Datong-Qinhuangdao line 20 kt-level combined heavy-haul train integration and innovation
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CLASSIFIER FUSION BASED ON EVIDENCE THEORY AND ITS APPLICATION IN FACE RECOGNITION 被引量:1
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作者 Yang Yi Han Chongzhao Han Deqiang 《Journal of Electronics(China)》 2009年第6期771-776,共6页
A multiple classifier fusion approach based on evidence combination is proposed in this paper. The individual classifier is designed based on a refined Nearest Feature Line (NFL),which is called Center-based Nearest N... A multiple classifier fusion approach based on evidence combination is proposed in this paper. The individual classifier is designed based on a refined Nearest Feature Line (NFL),which is called Center-based Nearest Neighbor (CNN). CNN retains the advantages of NFL while it has relatively low computational cost. Different member classifiers are trained based on different feature spaces respectively. Corresponding mass functions can be generated based on proposed mass function determination approach. The classification decision can be made based on the combined evidence and better classification performance can be expected. Experimental results on face recognition provided verify that the new approach is rational and effective. 展开更多
关键词 Nearest Feature line (NFL) Evidence combination Classifier fusion Face recognition
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A monolithic distributed phase shifter based on right-handed nonlinear transmission lines at 30 GHz 被引量:1
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作者 黄杰 赵倩 +2 位作者 杨浩 董军荣 张海英 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第12期451-455,共5页
The epitaxial material, device structure, and corresponding equivalent large signal circuit model of GaAs planar Schottky varactor diode are successfully developed to design and fabricate a monolithic phase shifter, w... The epitaxial material, device structure, and corresponding equivalent large signal circuit model of GaAs planar Schottky varactor diode are successfully developed to design and fabricate a monolithic phase shifter, which is based on right-handed nonlinear transmission lines and consists of a coplanar waveguide transmission line and periodically distributed GaAs planar Schottky varactor diode. The distributed-Schottky transmission-line-type phase shifter at a bias voltage greater than 1.5 V presents a continuous 0°–360° differential phase shift over a frequency range from 0 to 33 GHz. It is demonstrated that the minimum insertion loss is about 0.5 dB and that the return loss is less than-10 dB over the frequency band of 0–33 GHz at a reverse bias voltage less than 4.5 V. These excellent characteristics, such as broad differential phase shift, low insertion loss, and return loss, indicate that the proposed phase shifter can entirely be integrated into a phased array radar circuit. 展开更多
关键词 GaAs planar Schottky diode phase shifter right-handed nonlinear transmission lines monolithic microwave integrated circuit
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Study on Galloping Stability Mechanism of Conductor and Its Application to Anti-Galloping of Transmission Lines 被引量:1
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作者 YouChuanyong 《Electricity》 2005年第1期26-30,共5页
Galloping of conductor is a major hazard to safe operation of transmission lines. This paper introduces the basic galloping stability mechanism of conductor, design method of anti-galloping and the application of anti... Galloping of conductor is a major hazard to safe operation of transmission lines. This paper introduces the basic galloping stability mechanism of conductor, design method of anti-galloping and the application of anti-galloping double pendulum and integral eccentric pendulum in China. Galloping stability mechanism of conductor was established based on vertical galloping mechanism developed by Den Hartog and torsional galloping mechanism developed by O. Nigel. A design method of anti-galloping was derived and anti-galloping double pendulum and integral eccentric pendulum were developed. Applications to several transmission lines including a 500 kV transmission line of large span indicated that they have played important roles in anti-galloping. 展开更多
关键词 galloping of conductor stability mechanism transmission line anti-galloping double pendulum integral eccentric pendulum
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Research progress in CALPHAD assisted metal additive manufacturing
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作者 Ya-qing Hou Xiao-qun Li +5 位作者 Wei-dong Cai Qing Chen Wei-ce Gao Du-peng He Xue-hui Chen Hang Su 《China Foundry》 SCIE EI CAS CSCD 2024年第4期295-310,共16页
Metal additive manufacturing(MAM)technology has experienced rapid development in recent years.As both equipment and materials progress towards increased maturity and commercialization,material metallurgy technology ba... Metal additive manufacturing(MAM)technology has experienced rapid development in recent years.As both equipment and materials progress towards increased maturity and commercialization,material metallurgy technology based on high energy sources has become a key factor influencing the future development of MAM.The calculation of phase diagrams(CALPHAD)is an essential method and tool for constructing multi-component phase diagrams by employing experimental phase diagrams and Gibbs free energy models of simple systems.By combining with the element mobility data and non-equilibrium phase transition model,it has been widely used in the analysis of traditional metal materials.The development of CALPHAD application technology for MAM is focused on the compositional design of printable materials,the reduction of metallurgical imperfections,and the control of microstructural attributes.This endeavor carries considerable theoretical and practical significance.This paper summarizes the important achievements of CALPHAD in additive manufacturing(AM)technology in recent years,including material design,process parameter optimization,microstructure evolution simulation,and properties prediction.Finally,the limitations of applying CALPHAD technology to MAM technology are discussed,along with prospective research directions. 展开更多
关键词 metal additive manufacturing CALPHAD integrated computational material engineering powder bed fusion material design microstructure simulation
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Non-gyroscope DR and adaptive information fusion algorithm used in GPS/DR device
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作者 Li Qingli Xue Yongqi +1 位作者 Shang Yanlei Shi Pengfei 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第2期390-395,共6页
In view of the problems existing in GPS, a non-gyroscope DR is introduced. The operating principle and the algorithm of the GPS/DR device are also presented. By operating measured data synthetically, linear observatio... In view of the problems existing in GPS, a non-gyroscope DR is introduced. The operating principle and the algorithm of the GPS/DR device are also presented. By operating measured data synthetically, linear observation equations are obtained for the information fusion algorithm. This approach avoids model error due to linearizing nonlinear observation equations in the conventional algorithm, so that the stability of information fusion algorithm is improved and computation expenses are reduced. Field running experiments show that satisfactory accuracy can be obtained by the proposed navigation model and algorithm for the non-gyroscope GPS/DR device. 展开更多
关键词 non-gyroscope DR GPS integrated navigation system information fusion.
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Exploration of Rural Informatization and Urban-rural Information Fusion 被引量:3
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作者 HE Wei Library of Chongqing University of Technology,Chongqing 400054,China 《Asian Agricultural Research》 2012年第8期86-89,共4页
Based on the status quo of rural informatization and information service,this article conducts analysis and discussion of problems in rural informatization and urban-rural information fusion,using statistics. And corr... Based on the status quo of rural informatization and information service,this article conducts analysis and discussion of problems in rural informatization and urban-rural information fusion,using statistics. And corresponding countermeasures are put forward as follows: building rural information platform; strengthening information literacy training in rural areas and cultivating new farmers; making information network serve production and operation to increase jobs and income for farmers; developing rural e-commerce; enhancing network information security and prevention. 展开更多
关键词 RURAL inFORMATIZATION information SERVICE Tri-netw
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Study of fractal character of the fusion line in dissimilar welded joint
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作者 屈朝霞 张汉谦 王宝 《China Welding》 EI CAS 1999年第1期48-51,共4页
The fractal dimension of the fusion line in different dissimilar welded joints is measured with Box Dimension Method.The non scale region of the fusion line with fractal character is calculated. The fusion line in th... The fractal dimension of the fusion line in different dissimilar welded joints is measured with Box Dimension Method.The non scale region of the fusion line with fractal character is calculated. The fusion line in the dissimilar welded joint is proved to be a fractal structure. The change and influence factors of the fractal dimension of the fusion line are studied. 展开更多
关键词 dissimilar welded joint fusion line FRACTAL
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On Cultural Landscape Planning and Design of Xihan River Customs Line in Lixian County
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作者 CHEN Qi ZHOU Dongni YANG Bin 《Journal of Landscape Research》 2013年第Z3期43-46,共4页
This study explored the effective means of constructing characteristic urban cultural landscapes in the design of urban waterfront landscapes by combining with planning and design of Xihan River Customs Line and adher... This study explored the effective means of constructing characteristic urban cultural landscapes in the design of urban waterfront landscapes by combining with planning and design of Xihan River Customs Line and adhering to the theme of "cultural reproduction",tried to integrate cultural landscapes into ecological landscaping,so as to fully demonstrate signifi cance of urban cultural background for theoretic researches and practices of urban landscaping. 展开更多
关键词 Xihan River CUSTOMS line WATERFRONT ecological RETURN Landscape integration REPRODUCTION of cultural landscapes
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Broadband microwave frequency doubler based on left-handed nonlinear transmission lines
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作者 黄杰 顾雯雯 赵倩 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第3期500-505,共6页
A bandwidth microwave second harmonic generator is successfully designed using composite right/left-handed non- linear transmission lines (CRLH NLTLs) in a GaAs monolithic microwave integrated circuit (MMIC) techn... A bandwidth microwave second harmonic generator is successfully designed using composite right/left-handed non- linear transmission lines (CRLH NLTLs) in a GaAs monolithic microwave integrated circuit (MMIC) technology. The structure parameters of CRLH NLTLs, e.g. host transmission line, rectangular spiral inductor, and nonlinear capacitor, have a great impact on the second harmonic performance enhancement in terms of second harmonic frequency, output power, and conversion efficiency. It has been experimentally demonstrated that the second harmonic frequency is deter- mined by the anomalous dispersion of CRLH NLTLs and can be significantly improved by effectively adjusting these structure parameters. A good agreement between the measured and simulated second harmonic performances of Ka-band CRLH NLTLs frequency multipliers is successfully achieved, which further validates the design approach of frequency multipliers on CRLH NLTLs and indicates the potentials of CRLH NLTLs in terms of the generation of microwave and millimeter-wave signal source. 展开更多
关键词 GaAs planar Schottky diode frequency multiplier composite fight/left-handed transmission line monolithic microwave integrated circuit
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基于Stacking集成算法的混凝土28d抗压强度预测 被引量:1
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作者 李姣阳 《广东建材》 2024年第6期19-23,共5页
为实现混凝土28d抗压强度的精准预测并解决不同机器学习模型间相互独立不能优势互补的问题。本研究通过357组混凝土配合比数据构建数据库,并采用Stacking集成方法对3个单一机器学习模型(KNN、XGBoost和RF)进行集成预测研究。首先通过随... 为实现混凝土28d抗压强度的精准预测并解决不同机器学习模型间相互独立不能优势互补的问题。本研究通过357组混凝土配合比数据构建数据库,并采用Stacking集成方法对3个单一机器学习模型(KNN、XGBoost和RF)进行集成预测研究。首先通过随机抽样方法将数据库划分为训练集和测试集,然后分别进行了单一机器学习模型和集成模型的训练和测试集预测,最后采用平均绝对误差指标(MAE)、均方根误差指标(RMSE)和确定系数(R2)对模型的预测结果进行评价。结果表明,RF模型在三个单一机器学习模型(KNN、XGBoost和RF)中表现最好(MAE=3.0705,RMSE=4.1847,R^(2)=0.8817);此外,Stacking集成模型的预测性能优于任意单一模型,相较于单一模型中表现较好的RF模型,其预测性能实现了显著提升(MAE下降2.6%,RMSE下降9.8%,R2提升2.5%)。 展开更多
关键词 混凝土 28d抗压强度预测 Stacking集成算法 算法融合
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